THE 17th INTERNATIONAL SYMPOSIUM ON ANALYTICAL AND

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PROCEEDINGS OF

THE 17th INTERNATIONAL SYMPOSIUM ON ANALYTICAL AND ENVIRONMENTAL PROBLEMS 19 September 2011

Edited by Zoltán Galbács

SZEGED

SZAB SZEGED, HUNGARY

THE 17th INTERNATIONAL SYMPOSIUM ON ANALYTICAL AND ENVIRONMENTAL PROBLEMS

Organised by SZAB Kémiai Szakbizottság Analitikai és Környezetvédelmi Munkabizottsága

Scientific Committee Prof. Dr. RUDOLF KASTORI academician, Chairman (Novi Sad, Serbia) Dr. Zoltán Galbács, Secretary (Szeged, Hungary) Dr. Alex De Visscher (Calgary, Canada) Prof. Dr. Etelka Tombácz (Szeged, Hungary) Prof. Dr. Krystyna A. Skibniewska (Olsztyn, Poland) †Prof. Dr. Ferenc Gaál academician (Novi Sad, Serbia) Prof. Dr. Zeno Garban (Timisoara, Romania)

ISBN 978-963-306-146-6

Sponsors SZAB * The book was commissioned by the University of Szeged in the framework of the programme named: “Biopolis Park - Rehabilitation of the public areas of University town” * Galbács Zoltán

The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

CONTENTS

The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

Page (File on the CD) ENVIRONMENTAL PROTECTION MANAGEMENT BY MONITORING THE SURFACE WATER QUALITY IN SEMENICAREA…………………………...A11-14 CATALYTIC PROPERTIES OF CESIUM SALTS OF 12-MOLIBDOPHOSPHORIC ACID SUPPORTED ON SBA-15 MESOPOROUS SILICA…………A15-18 LEAD AND PESTICIDE REMOVAL BY CARBON BLOCK FILTER………...……A19-23 BIOGÁZ……………………………………………………………………………...…A24-37 NEHÉZFÉMEK EREDETÉNEK ÉS FELDÚSULÁSÁNAK VIZSGÁLATA EGY KÜLVÁROSI ÖVEZET TALAJÁBAN………………………………………………..A38-42 ROLE OF BACTERIAL AUXIN-LIKE COMPOUNDS AND SIDEROPHORES IN THE ROOT DEVELOPMENT AND HEAVY METAL UPTAKE OF SALIX VIMINALIS I. IN THE PRESENCE OF LEAD AND CHROMIUM……...………….A43-46 A TALAJVÍZ TOXIKUS ELEMTARTALMÁNAK TÉR- ÉS IDŐBELI VÁLTOZÁSA VÁROSI KÖRNYEZETBEN, SZEGEDEN…………………..………A47-51 APPLICATIONOF DIFFERENT PSEUDOMONAS AERUGINOSA STRAINS IN MEOR EXPERIMENT………………………….…………………………………..A52-55 UV-INDUCED PHOTOOXIDATION OF PHENYL UREA PESTICIDES TOXICOLOGY ASPECTS………………………………………………………….….A56-59 ALGADISK-INTRODUCTION OF A STARTING FP7 PROJECT (286887)…….…..A60-63 VACUUM-ULTRVIOLET PHOTOLYSIS OF NON-STEROIDAL ANTIINFLAMMATORY DRUGS………………………………………………………...…A64-67 INFLUENCE OF PRECURSORS ON STRUCTURE AND MAGNETIC PROPERTIES OF CuFe2O4 OBTAINED BY COPRECIPITATION……………….....A68-71 PECULIARITIES OF THE COMPARATIVE METALLOGRAMS OF THE UROCONCREMENTS HAVING URATES AS DOMINANT COMPONENT AND PHOSPHATES AS DOMINANT COMPONENT…………………….…………A72-75 SYNTHESIS AND CHARACTERIZATION OF Co(II) CARBOXYLATES RESULTED IN THE Co(NO3)2-1,3-PROPANEDIOL REDOX REACTION…………A76-80 SAMPLE PRETREATMENT AND ANALYTICAL METHOD DEVELOPMENT FOR DETECTING STROBILURIN PESTICIDES IN AQUEOUS MATRICES……..A81-84 ENVIRONMENTAL ND ECONOMIC ASPECTS OF BROWNFIELD REVITALISATION………………………………………………………………….…A85-90

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The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

SUSTAINABLE DEVELOPMENT AND DILEMMAS IN SUSTAINABILITY MEASUREMENT………………………………………………………………………A90-94 FORMÁZÓSZEREK JELENLÉTÉNEK HATÁSA A TALAJOLDAT SZERVESANYAG TARTALMÁRA…………………………………………..………A95-99 CONFORMATIONAL ANALYSIS OF PHOSPHORUS POLYMERS WITH FLAME RETARDANT PROPERTY…………………………………….…..A100-103 CONFORMATIONALANALYSIS OF BICYCLIC PHOSPHATE DERIVATIVES BY COMPUTATIONAL METHODS……………………………..A104-107 AN ASSESSMENT OF HEAVY METALS CONTAMINATION OF SOILS AND VEGETATION NEAR AN AGROTEHNICAL FARM FROM AREA TIMIS…….A108-111 A FÓLIA ALATTI TERMESZTÉSBŐL SZÁRMAZÓ FŰSZERPAPRIKA ŐRLEMÉNYEK FONTOSABB BELTARTALMI ÉRTÉKEINEK ALAKULÁSA………A112-115 THE EFFECT OF UV RADIATION ON THE MYCELIA GROWTH OF WHITEBUTTON MUSHROOM AND THE PATHOGENIC FUGI OF CULTIVATED MUSHROOMS……………………………………………...….A116-119 A CSAPVÍZTŐL A GLIKOLIG, A KÖRNYEZETI LEVEGŐTŐL A FÖLDGÁZIG; BENZOL ÉS TOLUOL KONCENTRÁCIÓ MEGHATÁROZÁS SZÉLES DINAMIKUS TARTOMÁNYBAN………………………………………………….A120-124 A VÁROSI BEÉPÍTETTSÉG HATÁSA A SZOLÁRIS RENDSZEREK MŰKÖDÉSÉRE: SZEGEDI VIZSGÁLATOK EREDMÉNYEI……………...…....A125-128 BIOSURFACTANT SYNTHESIS IN THE OIL EATER RHODOCOCCUS ERYTHROPOLIS MK1 STRAIN………………………………………………...….A129-133 DENDROKRONOLÓGIAI VIZSGÁLATOK PINUS SYLVESTRIS FAFAJON – ESETTANULMÁNY A DUNA-TISZA KÖZÉN………………………………..….A134-137 HABITAT CHANGES OF AN ALKALINE LAKE, SOUTH HUNGARY……..….A138-141 BIODEGRADATION OF UNCTUOUS WASTES OF FOOD INDUSTRY…….…A142-145 AZ OPTIMÁLIS KÖRNYEZETI MAGNÉZIUM ELLÁTOTTSÁG DAGANETELLENES HATÁSA………………………………………………...…..A146-151 MOBIL AND TOTAL FORMS OF SOME TRANSITIONAL METAL CATIONS IN FOOD CHAIN OF BLACK CURRANTS CULTIVATION AND PROCESSING……………………………………………………………..…..A152-154 EFFECT OF SOIL PARTICLE SIZE ON COPPER AVAILABILITY…………..…A155-158

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The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

REPRODUCIBILITY AND ACCURACY PROBLEMS OF THE GASCHROMATOGRAPHIC RESPONSE FACTORS FOR THE REACTION PRODUCTS RESULTING FROM THE CATALYTIC BIO-ETHANOL CONVERSION…………………………………………………………………….…A159-162 ORGANIC PRODUCTION IN THE FUNCTION ON HEALTHY AND SAFE FOOD…………………………………………………………….……..A163-167 KÜLÖNBÖZŐ NPK KEZELÉSEK HATÁSA A CSEMEGEKUKORICA TERMÉKMINŐSÉGÉRE…………………………………………………………....A168-171 WASTEWATER CHARACTERISATION OF SCREEN PRINTING…………..….A172-175 POTENTIAL ADVERSE EFFECT OF ENDOCRINE DISRUPTORS AT LOW DOSES………………………………………………………………..…...A176-179 PSEUDO-PERSISTENT POLLUTANT IN THE ENVIRONMENT: EMERGING SUBSTANCES…………………………………………………..….…A180-184 ÚTBURKOLATOK ÖSSZGAMMA-SUGÁRZÁSÁNAK VIZSGÁLATA………..…A185-188 FORMALDEHYDE IN SCREEN PRINTING INDOOR………………………..…..A189-192 CADIUM LEVEL IN SOME TISSUUES AND ORGANS FROM WILDBOAR..…A193-196 LEAD LEVELS IN SOIL-WATER-PLANT CHAIN FROM A FORESTY ECOSYSTEM……………………………………………………………………..….A197-199 SAWDUST AS LOW-COST NATURAL ADSORBENT FOR REMOVAL OF Cu(II) IONS FROM AQUEOUS SOLUTIONS……………………………..…..A200-203 IM MEMORIAM Prof. Gaál Ferenc………………………………………...……A204-206 SOME CONSIDERATIONS CONCERNING THE MS ANALYSIS OF COMPLETELY PROTECTED THIOGLYCOSIDES WITH HETEROCYCLIC AGLICONE…………………………………………………..….A207-209 NEUROTOXICITY OF MANGANESE ANALYSED BY A NOVEL COMBINED ELECTROPHYSIOLOGICAL_BEHAVIORAL RECORDING SYSTEM………………………………………………………………………….….A210-214 THE APPLICATION OF ZVI BASED IRON-GELS IN REMEDIATION TECHNIQUES…………………………………………………………………...…..A215-218 EFFECTS OF THE AD LIBITUM CONSUMPTION OF ETHANOL ON THE SERUM LIPIDS METABOLITES AND ON SOME SERUM BIOMETALS STUDIED N AN ANIMAL MODEL…………………………….…..A219-222 OIL EXTRACTION FROM NANNOCHLOROPSIS OCULATA MICROALGAE FOR BIODIESEL PRODUCTION……………………………...…A223-226

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The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

REZALIM-ICIA’S METHOD FOR DETERMINATION OF PAHs FROM WATER SAMPLES……………………………………………………….....A227-230 WOOD-A RENEWABLE RESOURCE FOR PRODUCTION OF SUGAR AND BIOFUEL…………………………………………………………….A231-234 SOIL POLLUTION ASSESSMENT IN THE BAIA MARE AREA AFTER PARTIAL CLOSURE OF ORE PROCESSING ACTIVITIES…………….A235-238 APPLYING OF MULTIVARIATE ANALYSIS TO STUDY THE CORRELATION OF MERCURY AND OTHER TRACE ELEMENTS DISTRUBUTION IN SOIL FROM A CITY FROM NW ROMANIA………….…..A239-242 THE EFFECT OF NITROGEN ON MAIN CHARACTERISTICS OF BIODIESEL OBTAINED FROM RAPESEED OIL………………………………...A243-246 THE EFFECTS OF IRRIGATION REGIME AND NITROGEN RATES ON RAPESED YIELD……………………………………………………………….A247-250 LEVELS OF POLYCYCLIC AROMATIC HYDROCARBONS IN MONITORING WELLS FROM MUNICIPAL LANDFILL DETERMINED BY SOLID_PHASE MICROEXTRACTION AND GAS CHROMATOGRAPHY/FLAME IONIZATION DETECTION……………….……A251-254 BIODEGRADATION STUDIES OF POLYLACTIC ACID COPOLYMERS….….A255-258 PORPHYRIN BASED-SYSTEMS FOR THE DETECTION OF RECOVERBLE METALS FROM Li-ION BATTERIES, MINI-REVIEW….….….A259-262 ELECTROCHMICAL ANALYSIS OF SOLID POLYMER ELECTROLYTE MEMBRANES USED IN LITHIUM-BASED BATTERIES…………………….…A263-266 MASS-SPECTROMETRY USED IN CHARACTERISATION OF PIGMENTS….A267-270 REMOVAL OF ESCHERICHIA COLI FROM WATER BY SYSTEM BASED ON PHOSPHORUS – CONTAINING SYNTHETIC PREFORMED POLYMER…A271-274 IN VITRO MUTAGENICITY EVALUATION OF IRON OXIDE NANOPARTICLES BY THE BACTERIAL REVERSE MUTATION ASSAY…………...A275-278 ADSORPTION OF PHENOLIC COMPOUNDS FROM WATER ON POLYMERIC ADSORBENTS WITH OLEFIN GROUPS……………………….…A279-282 USE OF IMPREGNATED RESINS AS ADSORBENTS IN VIEW OF HEAVY METALS REMOVAL FROM AQUEOUS SOLUTION………………….A283-286 STUDIES ON COLUMN ADSORPTION OF ARSENIC (V) FROM A REAL WATER ON DEHPA-IMPREGNATED XAD-8 RESIN…………………………...A287-290

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The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

STUDIES ON THE PURIFICATION OF WASTEWATERS WITH HIGH NICKEL IONS CONTENT…………………………………………………………..A291-294 STUDIES REGARDING THE TURNING TO ACCOUNT OF THE WASTE RESULTING FROM COAL EXPLOITATION…………………………...A295-298 . ELECTROCHEMICAL SYNTHESIS OF POLY-3-AMINOPHENYL BORONIC ACID IN SULFURIC ACID SOLUTION……………………………....A299-302 THERMAL BEHAVIOUR OF THE COPOLYMERS BASED ON STYRYLPHOSPHONIC ACID………………………………………………….…..A303-306 DOES AN AROMATIC CHLORIDE SUBSTITUTE POSITION INFLUENCE THE AGGREGATION PROPERTIES OF DIRECT DYES?..............A307-310 5-(4-PYRIDYL)DIPYRROMETHANEE-SILICA SOL SYNTHESIS AND LUMINESCENT PROPERTIES……………………………………………………..A311-314 INFLUENCE OF SYNTHESIS PARAMETERS ON LUMINESCENCE EMISSION PROPERTIES OF SOME SOL-GEL DERIVED Eu3+ DOPED WILLEMITE PHOSPHORS………………………………………………...……….A315-318 SYNTHESIS AND LUMINESCENCE PROPERTIES OF SOME Ce3+ DOPED SILICA SOLS………………………………………………………………A319-322 UNSATURATED PHOSPHONIC ACID, A NOVEL PRECURSOR TO FABRICATE METAL ORGANIC FRAMEWORKS……………………………….A323-326 SYNTHESIS AND CHARACTERIZATION OF A NEW METAL ORGANIC FRAMEWORK………………………………………………………….A327-331 REACTIVE YELLOW 125 DEGRADATION USING TITANIUM DIOXIDE DOPED WITH N…………………………………………………………A331-334 REMOVAL OF PHARMACEUTICALS FROM WASTEWATERS BY ELECTROOXIDATION……………………………………………………………..A335-338 ELECTROCHEMICAL BEHAVIOR AND DETERMINATION OF ARSENIC (III) FROM WATER USING Ag-DOPED-ZEOLITE-CARBON NANOTUBES COMPOSIT ELECTRODE………………………………………….A339-342 POLYALUMINIUM CHLORIDE COAGULATION IN DRINKING WATER TREATMENT………………………………………………………………………..A343-346 HEAVY METALS IN PLANTS GROWN ON NEW FLY ASH DEPOSITS………A347-350 COLOUR EXPRESSION IN THE CIELAB COLOUR SCALE OF NEW STILBENE DYES……………………………………………………………………A351-354

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The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

EXPERIMENTAL STUDY OF THE INTERACTION OF ONE LOCAL ANESTHETIC WITH A CELLULOSE TYPE SUPPORT………………………….A355-358 SYNTHESIS OF TRIPODAL CYCLOTRIVERATRYLENE (CTV) DERIVATIVES AS SCAFFOLDS FOR BINDING SUGARS…………………...…A359-361 SYNTHESIS OF ULTRAFINE GAHNITE (ZnAl2O4) NANOCRYSTALS BY CPRECIPITATION METHOD……………………………………………….…A362-365 COAGULATION CHRACTERISTIC OF ELECTROCHEMICLLY PREPARED POLYALUMINIUM CHLORIDE ON HUMIC ACID REMOVAL FROM WATER………………………………………………………...A366-370 INVENTORY OF MEAT INDUSTRY POLLUTERS IN VOJVODINA REGION..A371-374 PHOTOCATALYTIC DEGRADATION OF METHYLENE BLUE FROM WATER USING UV IRRADIATION…………………………………………….…A375-378 THE POTENTIAL HEALTH RISKS CAUSED BY DECADES OF HEAVY METAL POLLUTION IN RESITA CITY, CARAS-SEVERIN COUNTY, ROMANIA……………………………………………………………………….…..A379-383 ENVIRONMENTAL FRIENDLY ELECTROCHEMICAL DETERMINATION OF ASPIRIN FROM ALKALINE AQUEOUS SOLUTION……………………..…A384-387 SYNTHESIS, CHARACTERISATION AND PHOTOCATALYTIC APPLICATION OF COPPER-MODIFIED ZEOLITE……………………………....A388-391 REMOVAL OF TURBIDITY AND ORGANIC LOAD FROM SURFACE WATER BY COAGULATION-FLOTATION……………………………………....A392-395 ELECTROCHEMICAL DEGRADATION OF DRUG RESIDUES FROM WATER……………………………………………………………………....A396-399 ADSORPTION OF PHENOL AND P-CHLOROPHENOL FROM AQUEOUS SOLUTIONS ON POLYMER ADSORBENT………………………....A400-404 STUDENT’S HEALTH AND DIET HABITS IN FACULY OF FOOD PRODUCTS TECHNOLOGY FROM TIMISOARA, ROMANIA……………….....A405-408 UREA FORMALDEHYDE COATED WITH SILICA (NANO) CAPSULES SYNTHESIS IN ULTRASONIC FIELD…………………………………………….A409-412 SILICA AEROGELS SYNTHESIZED ITH BUTYL-4-METHYLPYRIDINIUM TETRAFLUOROBORATE………………………………………………………..…A413-416 LOGISTIC KINETIC MODEL FOR CHLORINATED POLY AROMATIC HYDROCARBONS (CLPAHS) ACTIVITY IN CANCER SIGNALING………….A417-420

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The 17th Int. Symp. on Analitical and Environmental Problems, Szeged, 19 September 2011

ASPECTS OF TRANSFER HEAVY METALS IN RASPBERRY (RUBUS IDAEUS) GROWN IN THE GEOGRAPHIC AEA OF NADRAG (CARAS-SEVERIN)…………………………………………………………………A421-424 ACCUMULATION OF HEAVY METALS IN NATIVE PLANTS GROWING ON A CONTAMINATED OCna DE Fier siTE (ROMANIA)…………………...….A425-429 ELECTROCHEMICAL DETECTION OF PENTACHLOROPHENOL FROM WATER AT CARBON NANOFIBERS-EPOXY COMPOSITE ELECTRODES……………………………………………………………………….A430-433 REMOVAL OF HUMIC ACID FOM WATER BY SORPTION…………...………A434-437 MODEL BASED GROUNDWATER POLLUTION PREDICTION………………..A438-441 A PASSZÍVHÁZ PROBLEMATIKA………………………………………………..A442-445 A VÁROSI KÖZLEKEDÉS ÉS A ZÖLD FELÜLETEK KAPCSOLATRENDSZERE SZEGEDI TAPASZTALATOK ALAPJÁN………………...………A446-449 SZEGED VÁROS KÖZLEKEDÉS-KÖRNYEZETE A MÚLTBAN ÉS A JELENBEN…………………………………………………………………..…....A450-454 A SZEGEDI KÖZLEKEDÉS OKOZTA KÖRNYEZETTERHELÉS HATÁSRENDSZERE………………………………………………………………..A455-459 AZ AUTÓPÁLYA ÉS A KÖRGYŰRŰ HATÁSA A SZEGEDI KÖZLEKEDÉS KÖRNYEZETTERHELÉSÉRE…………………………….……..A460-464 A FOTOSZINTETIKUSAN AKTÍV BESUGÁRZÁS ÉS A LEVELEK EZZEL ÖSSZEFÜGGŐ NÉHÁNY ÉLETTANI FOLYAMATÁNAK ALAKULÁSA TÁMRENDSZERES ÉTKEZÉSI PAPRIKA ÁLLOMÁNYBAN….A465-468 EVALUATION OF SOME PHYSIOLOGICAL PARAMETERS OF ALNUS GLUTINOSA (L.) GAERTN. IN CONTAINER NURSERY PRODUCTION…...…A469-472 KÜLÖNBÖZŐ KÁLIUMFORMÁK HATÁSA PAPRIKANÖVÉNYEK LEVELEINEK FOTOSZINTETIKUS AKTIVITÁSÁRA ÉS VÍZFOGYASZTÁSÁRA…………………………………………………...………..A473-476 A PORSZENNYEZÉS HATÁSA A MEZŐGAZDASÁGI NÖVÉNYEK PRODUKCIÓJÁRA………………………………………………………………….A477-482 Megjegyzés: AZ ÍGY KIEMELT ELŐADÁSOK SZEGEDI VONATKOZÁSÚAK!

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

ENVIRONMENTAL PROTECTION MANAGEMENT BY MONITORING THE SURFACE WATER QUALITY IN SEMENIC AREA Dana SÂMBOTIN, Ana Mariana DINCU, Adrian COROIAN, Mihaela PĂTRĂŞCOIU Research group: Banat University of Agricultural Sciences and Veterinary Medicine Timişoara Romania e-mail: [email protected] ABSTRACT Environment seems to have been the war against all. In fact recently most people polluted the environment and those few are cared for his cleaning. Today, the relationship evolved as societies have changed in favour of ensuring environmental protection. With modern technology, performance, monitoring the environment becomes part of human activity ever more necessary, more possible and more efficient. The quality of the environment, its components: air, water, soil, plants, vegetable and animal products, it’s a condition “sine qua non” for the life of the modern man. The consequences of environmental pollution are so dangerous that modern man cannot afford considering them. Water, a basic element of life on our planet, has a dynamic circuit that leads to renewal and refreshing the natural water reserves. Through this paper I study the environmental quality by monitoring the shallow waters from the Semenic – Gărâna area. INTRODUCTION Semenic resort is in Caras-Severin County, and belongs to the Semenic Mountains which are part of the southern group of Western Carpathians, culminating with Piatra Goznei Peak (1447 m) and Semenic Peak (1445 m). This is an important hydrographical node – “the water castle of Banat "- from which Timis, Nera, Barzava spring. This whole mountain aggregate forms a major tourist area, where one can practice a complex tourism. Agricultural production is characterized by a high pollutant potential, resulted in the nature of the production processes used to enhance production and growth of the volume of agricultural products for consumption. In this paper we followed the amount of the ammonium, nitrites and nitrates from the waters in the area that we researched. We all know that if the waters are polluted we cannot drink it, and we also know that it is cheaper to prevent than to treat. MATERIALS and METHODS Territorial and geographical location for this study of the drawing points of surface water in order to make laboratory tests was conducted in three locations namely Garana, Valiug and Semenic. As the hydrostatic parameter is variable depending on time parameter it is necessary to collect water samples at different times of the year, and thus it can be captured the dynamics

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

of concentration variation in the various salts which give groundwater salinity content. The establishment schedule to collect water sampling was done according to the calendar period, rainfall and temperature factor regime. So water samples were collected four times in 2010 respectively January, April, September and December. Transport of samples, under conditions of adequate insulation, to the chemical analysis laboratory of the Faculty of Horticulture and Forestry USAMVB Timisoara and the analysis regarding the pollutants factors NH4 +, NO-3 and NO-2 and pesticides. Collection and storage of water samples were collected in accordance with ISO 566710, ISO 2852, from the surface and deep waters from village wells. Water samples were collected in plastic containers or glass of about one liter. Before use the containers were washed with nitric acid diluted with distilled water and then rinsed with water for analysis. The method used is the spectrophotometric method for determining ammonium Spectroquant Ammonium Merck 14,752. The content of nitrate, nitrite and ammonium was determined colorimetrically using rapid tests Aqua Merck, the SQ 118 spectrophotometer at wavelengths: 515, 525 and 690 nm for nitrate, nitrite and respectively ammonium. RESULTS Most of the EU population has access to clean water in abundant quantities, but they don’t realize that many of their activities pollute water, damaging the environment and even their health. All polluted water, either in households, industry or agriculture return, one way or another, into nature, polluting the environment. Even in the mountain areas the pollutant potential increased. Semenic plateau has an inherent characteristic, less common in other mountainous ranges. Semenic plateau is barren, with a low level of forestation in the highlands. The place of the forest was taken by meadows and alpine meadows, which give the plateau a special characteristic. Under these conditions, there are mountain villages located at high altitudes such as Garana, which is located at about 1100 m. The extension of inhabited hearths at such altitudes entailed the development of livestock production, especially cattle and sheep industry. In this context, it was mandatory to improve the quality and quantity of plant mass obtained from natural grasslands. This objective can be achieved through increased production in these utilities, especially by increasing the amounts of fertilizer factors. We refer here to the chemicals, especially chemical fertilizers, which are characterized by a high pollutant potential. Water is certainly the most important of these components because of the great dispersal capabilities in the territory of the results of polluting factors. In the alpine area of Semenic plateau there is the lake "Trei ape” which is fueled by a series of streams that collect their water from the surrounding slopes, and in the subalpine area of the Semenic plateau there is Văliug Lake. On the northwestern slope of the Semenic plateau is the retention basin of the river Bârzava, which together with the Văliug Lake ensure Resita’s water consumption. In these conditions it is understood why it is necessary the development and use of codes of good agricultural practices, which must be at hand of any agricultural producer, and that should clearly show, using friendly methods and practices to the environment, the ways of reducing pollution and degradation of water and soil quality, of achieving a livestock production under conditions of maximum environmental protection. It is well known that environmental protection, therefore water, is expensive and water remediation costs are much higher than if we prevented it in the first place the contamination. Groundwater quality is very good, as it filters through the soil, but it is generally found in small quantities, and can only serve for small communities; in addition it has a very low self-purification capacity.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

One of the most important goals of the code of good agricultural practices is to ensure protection of water, an essential element of any life forms, whose properties ensure the quality of agricultural products, but at the same time, it is vulnerable to agricultural activities in all branches and agricultural production areas. In general, deep water contains ammonia. Instead, surface waters are under direct and immediate effect of ammonia from the decomposition of organic matter or manure. Of particular importance is rainfall, which may have a dual role. Surface rainfall creates leaks that could lead to soluble products of ammonia or even organic sources from which it can be derived to natural water courses which are taken by the collector river and brought to final discharge into the sea. For this set of tests, water samples were collected from surface water sources. In Tables 1, 2 and 3 will be presented the results of tests carried out during 2010. As we can see in the following tables, neither ammonium, nitrites nor nitrates did not exceed the maximum accepted limit. Although for nitrates there were some big values, we can say that the water is not polluted, and it is save for the people and not only. The highest results were registered in April, in all three areas researched. Table 1. The results concerning the content of ammonium, nitrites and nitrates from Semenic area Semenic Ammonium 0,50mg/l Nitrites 0,50mg/l Nitrates 50 mg/l

January 0.09

April 0.14

September 0.10

December 0.10

0.06

0.10

0.10

0.04

24.1

26.4

20.0

19.1

Table 2. The results concerning the content of ammonium, nitrites and nitrates from Gărâna area Gărâna Ammonium 0,50mg/l Nitrites 0,50mg/l Nitrates 50 mg/l

January 0.10

April 0.19

September 0.18

December 0.20

0.09

0.10

0.08

0.08

30.4

31.1

24.6

25.0

Table 3. The results concerning the content of ammonium, nitrites and nitrates from Văliug area Văliug Ammonium 0,50mg/l Nitrites 0,50mg/l Nitrates 50 mg/l

January 0.02

April 0.04

September 0.03

December 0.03

0.05

0.5

0.02

0.03

15.4

16.0

12.9

12.0

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

CONCLUSIONS After the researches were done in the field and in laboratory, after reading the specialty books, national or foreign, we can draw the following conclusions: 1. We can notice that the biggest values registered were in April, when the quantity of the precipitations is the highest. 2. No matter the location, the content of ammonium, nitrites and nitrates don’t exceed the maximum admitted limit. 3. In the studied territory the shallow waters can be used as potable water sources, with the condition to respect the other chemical compositions norms. 4. In the area the tourism can be practiced, because the water has no danger either for the people, animals or flora. 5. We must take good care of the environment and of the waters, it is cheaper to prevent than to treat and this is a thing that the next generation is going to inherit from us. LIST OF REFERENCES . [1] Alexa Ersilia, Finichiu M., „Poluarea biologică a surselor de apă”, Consfătuirea de specialitate Bacău, USSM filialele Bacău şi Iaşi, iunie 1984; [2] Alexa Ersilia, „Pesticide şi remanenţa lor”, Ed. Eurobit, Timişoara, 2003; [3] Berca M., „Relaţiile dintre erbicide şi mediul înconjurător”, Ed. Ceres, Bucureşti, 1985; [4] Sâmbotin Liviu, „Managementul exploataţiilor agricole”, Ed. Mirton, Timişoara, 1999; [5] *** „Geografia României”, Vol. I, Editura Academiei Bucureşti, anul 1983; [6]. ***http://europa.eu.int/comm/environment.html - Pagina web a Directoratului General pentru Mediu al Comisiei Europene; [7] *** SR 1343-1:2006- Alimentări cu apă potabilă pentru localităţi urbane şi rurale; [8] *** SR 3048/2 Apă potabilă. Determinarea conţinutului de nitriţi. Metoda prin spectometrie de absorbţie moleculară. Standard de stat. Consiliul Naţional pentru Ştiinţă şi Tehnologie, Institutul Român de Standardizare, 1996.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September,2011

CATALYTIC PROPERTIES OF CESIUM SALTS OF 12MOLYBDOPHOSPHORIC ACID SUPPORTED ON SBA-15 MESOPOROUS SILICA Alexandru Popa, Viorel Sasca, Orsina Verdes, Livia Avram, Ianasi Catalin Institute of Chemistry Timişoara, Bl.Mihai Viteazul 24, 300223 Timisoara, Romania e-mail: [email protected] ABSTRACT The Cs salt of molybdophosphoric acid Cs2.5H0.5PMo12O40 (CsHPM) was supported on SBA15 in the concentration of 20, 30 and 40 wt. % loadings. The structure and texture of these CsHPM/SBA-15 composites were studied by XRD, FT-IR and micro-Raman spectroscopy, BET and pore size distribution, SEM-EDS. Thermal stability was investigated by thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The dehydration of ethanol was used to probe the catalytic properties of the CsHPM samples incorporated on the silica matrix. The main reaction products obtained on acid (dehydration) catalytic centres were ethylene and diethyl ether, and respectively acetaldehyde which was obtained on redox (dehydrogenation) catalytic centres. INTRODUCTION Heteropolyacids (HPAs) with Keggin structure and their salts unsupported and supported on different materials may be used for both acid and redox catalysis, as well as in media as heterogeneous (gas–solid and liquid–solid systems) or homogeneous catalysts [1-3]. HPAs are usually impregnated on different porous materials with high surface area (hexagonal mesoporous silica, titania, polymers, molecular sieves) [4-6]. Increasing the amount of surface acidic sites is an important task for the development of useful solid acids applied in different catalyzed reactions. Partial substitution of protons by different cations may result in changes to the number of available surface acidic sites. For example, the salt Cs2.5H0.5PW12O40 was reported as superior catalysts which exhibit significantly higher activity than the parent acid in gas phase acid-catalyzed reactions In order to obtain highly dispersed heteropolyacid species, the Cs salt of molybdophosphoric acid Cs2.5H0.5PMo12O40 (CsHPM) was supported on SBA-15 in the concentration of 20, 30 and 40 wt. % loading. In this work we characterised the texture of these supported HPAs salts in reference to the bulk solid heteropolyacids and investigate their catalytic activity for ethanol conversion. MATERIALS and METHODS The bulk CsHPM with Cs/Keggin unit ratio of 2.5 was prepared from aqueous solutions of CsNO3 and H3PMo12O40. The Cs2.5H0.5PMo12O40 (CsHPM) - SBA15 composites were synthesised as follows: first caesium nitrate was impregnated by aqueous incipient wetness onto SBA-15 molecular sieve, dried and calcined at 300°C and finally 12molybdophosphoric acid was impregnated by a similar aqueous impregnation route. The CsHPM was deposited in the concentration of 20, 30 and 40 wt. % loadings. Mesoporous silica SBA-15 was synthesized according to the procedure developed by D.Zhao et al. by the hydrolysis of tetraethyl orthosilicate using as surfactant a P123 block copolymer [19, 20]. The texture of CsHPM supported on SBA-15 was studied by SEM-EDX and low temperature nitrogen adsorption technique. Catalytic conversion and selectivities were measured for vapour phase ethanol dehydration reaction at 250, 275 and 300°C. A differential tubular stainless steel flow reactor,

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September,2011

which was placed into a tubular furnace, was used for the gas phase ethanol dehydration reaction. Before each experiment, 100 mg of the synthesized catalyst was placed in the middle of the stainless steel tubular reactor. Liquid ethanol (99.8% Riedel de Haen) was pumped by a syringe pump at a flow rate of 1.2 ml/h into an evaporator where it is mixed with nitrogen and air to adjust the reactor feed composition. Ethanol was mixed with nitrogen and air at a ratio of Et-OH : N2 : O2 = 1:3.5:0.4 in the evaporator. The total flow rate of the vapour stream was kept constant at 30 ml/min. The composition of the reactor effluent stream was analyzed using a gas chromatograph (Hewlett Packard 5890 GC), which was equipped with a (FID) flame ionization detector. A Poropak QS column was used in the analysis of the product stream. In GC analysis, ethylene, acetaldehyde, ethanol and diethyl - ether peaks were observed at 3.93, 11.75, 12.93 and 15.65 min, respectively. All the connection lines were heated to 150°C to prevent condensation. RESULTS The N2 adsorption-desorption isotherms of the parent mesoporous silica SBA 15 and CsHPM - SBA15 composites show a typical adsorption curve of type IV as defined by the IUPAC. An obvious hysteresis loop at a relative pressure of p/p0 = 0.4 - 0.9 is evidenced for the parent mesoporous silica SBA 15 and CsHPM - SBA15 composites. The specific surface area, pore volume and pore diameter determined from the isotherms using the BJH method are given in Table 1. For parent Cs2.5H0.5PMo12O40 a narrow hysteresis loop is observed (not shown). The bulk Cs2.5H0.5PMo12O40 salt displayed surface area of 103 m2/g and a pore volume 0.086 cc/g that correspond to the average pore diameter of 34 Å. The pore size distribution curves of parent mesoporous silica SBA 15 have narrow pore size distribution within mesopore range with a maximum at 62 Å. The pore size distribution curves of CsHPM - SBA15 composites have one maximum within mesopore range at approximately the same values as in the case of pure mesoporous SBA15. Table 1 Textural properties of Cs2.5H0.5PMo12O40 - SBA15 composites. Sample Mesoporous silica SBA15 20 CsHPM in SBA15 30 CsHPM in SBA15 40 CsHPM in SBA15 CsHPM

Specific surface area (m2/g) 725

Pore volume BJHDes (cc/g) 1.19

Average pore diameter BJHDes (nm) 6.2

476 445 397 103

0.59 0.64 0.47 0.086

6.1 6.2 6.1 3.4

The dehydration of ethanol was used to probe the catalytic properties of the CsHPM samples incorporated on the silica matrix. Catalytic activity of the synthesized CsHPM–silicabased nanocomposite catalysts for vapour phase ethanol dehydration reaction was tested in a fixed bed flow reactor. The main reaction products obtained on acid (dehydration) catalytic centres were ethylene (ET) and diethyl ether (DEE), and respectively acetaldehyde (ACA) which was obtained on redox (dehydrogenation) catalytic centres. Ethylene and DEE are due to dehydration reactions occurred on the acid sites of the catalyst, while acetaldehyde formation

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September,2011

through a dehydrogenation reaction indicated the presence of basic sites. In the effluent leaving the reactor were detected also unreacted alcohol and minor quantities of COx. The conversion of ethanol and selectivity were calculated as follows: Conversion = moles of ethanol reacted/moles of ethanol in the feed x 100 (1) Selectivity was calculated in carbon-based values: Selectivity = moles of product desired/moles of reacted ethanol x 100 (2)

Ethanol conversion 100 90 Conversion, %

80 70 60 50 40 30

Cs2.5PM

20

20Cs2.5PM/SBA15

10

30Cs2.5PM/SBA15 40Cs2.5PM/SBA15

0 0

100

200

300

400

500

600

Time on stream, min

Figure 1 Ethanol conversion values obtained with pure CsHPM and CsHPM - SBA15 composites at 300°C Ethanol conversion over pure CsHPM and 40CsHPM - SBA15 catalysts has relatively constant values during the time on stream but values of conversion are higher for supported sample. For 20CsHPM - SBA15 and 30CsHPM - SBA15-supported catalysts the values of ethanol conversion are lower in comparison with pure CsHPM ones and a continuing decrease of them with time on stream is evidenced (Figure 1). The CsHPM–silica-based nanocomposite catalysts synthesized here were found to be very efficient for ethylene formation from ethanol. The highest ethylene yield values were obtained with CsHPM and 40CsHPM - SBA15 catalysts. With these catalysts, selectivity of ethylene has values of around 75 - 85% obtained at reaction temperature of 300 °C. Ethylene selectivity for pure CsHPM and 40CsHPM - SBA15 catalysts has relatively constant values during the time on stream (as in the case of Et-OH conversion) but values of ET selectivity are higher for CsHPM sample. So, after reaction for 500 min, the ethylene yields over 20CsHPM - SBA15 and 30CsHPM - SBA15 at 300°C reached 32% and 58%, respectively. The DEE selectivity increased with time on stream for 20CsHPM - SBA15 and 30CsHPM - SBA15 -supported catalysts while for pure CsHPM and 40CsHPM - SBA15 catalysts remain nearly constant with the increasing of time on stream. The values of DEE selectivity for 20CsHPM - SBA15 reach the maximum values after 5 h and then remain almost constant. The third main product obtained in the catalyst test experiments was acetaldehyde. As shown in Fig. 2, acetaldehyde formation was observed in selectivity below 20% . Among the catalysts tested, highest acetaldehyde selectivities were obtained with 20CsHPM - SBA15

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September,2011

catalysts tested at 300 °C. Acetaldehyde (ACA) which is known to be produced on redox centres resulted in significant amount especially on supported catalysts in comparison with pure CsHPAs ones. However, supported 20CsHPM - SBA15 led to higher quantities of ACA, especially after 5 h on stream. Thus, the very high dispersion of the HPAs on high surface area molecular sieve yielded an active catalyst for ethanol conversion and for acetaldehyde formation. The acetaldehyde selectivity increased gradually with time on stream from 5% to 17% in the case of 20CsHPM - SBA15. Acetaldehyde selectivity 25 Cs2.5PM 20Cs2.5PM/SBA15

Selectivity, %

20

30Cs2.5PM/SBA15 40Cs2.5PM/SBA15

15 10 5 0 0

100

200

300

400

500

600

Time on stream, min

Figure 2 ALAC selectivity versus time on stream for CsHPM and CsHPM - SBA15 composites at 300°C CONCLUSIONS • In this study is described a procedure for supporting insoluble Cs acid salts on mesoporous SBA-15 by two-step sequential impregnation with a variation of active phase content (2040 wt. %). • Parent CsHPM and CsHPM - SBA15 composites have showed both acidic and redox properties and therefore the reaction products obtained are ethylene and DEE on acidic centres and acetaldehyde on redox catalytic centres, respectively. • The favourable effect of CsHPM deposition into the silica pores for oxidehydrogenation pathway to acetaldehyde results from the higher values of ACA selectivity especially for 20CsHPM - SBA15 composites. LIST OF REFERENCES [1] N. Mizuno, M.Misono, Chem. Rev. 98 (1998) 199. [2] F.Cavani, Catal. Today 41 (1998) 73. [3] A. Popa, V. Sasca and J. Halasz, Appl. Surf. Sci. 255 (5) (2008)1830. [4] G.D.Yadav, G.George, Catal. Today 141 (2009) 130. [5] A. Popa, V. Sasca, E. E. Kiss, R. Marinkovic-Neducin, M. T.Bokorov, I. HolclajtnerAntunović, Mater. Chem. Phys. 119 (3) (2010) 465. [6] A. Popa, V. Sasca, E. E. Kiss, R. Marinkovic-Neducin, I. Holclajtner-Antunović, Mater. Res. Bull. 46 (2011) 19.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

LEAD AND PESTICIDE REMOVAL BY CARBON BLOCK FILTER Marjana Simonič University of Maribor, Faculty of Chemistry and Chemical Engineering, Smetanova 17, 2000 Maribor, Slovenia, tel: +386 2 22 94 472, Fax: +386 2 252 77 74, E-mail: [email protected]

ABSTRACT The aim of the research was to determine the reduction of pesticide, lead, chlorine and bacteria in drinking water after the filtration using carbon block filter. The effectiveness of filter was determined by general and physico-chemical analysis on drinking water samples before being treated with filter. We made some rapid test using drinking water test WS–425B. The results show that the total hardness in filtered water decreased at the start, while the concentration of K+ increased tremendously. After about 10 L of water was used, the hardness of water increased to the value of untreated drinking water, while the concentration of K+ decreased down to 20 mg/L. The concentrations of atrazine and lead in water samples were reduced after being treated with filter. Nitrate-ions were reduced and probably exchanged with chloride-ions from filter due to increased electrical conductivity. Keywords:drinking water, carbon block filter, atrazine

INTRODUCTION Very tight carbon block filters can remove cysts simply because of their restricted pore size. Multi-Pure blocks are absolute 0.5 micron filters, making cryptosporidium organisms about ten times too large to go through the pores. Thus the very dense carbon block filters could be effective against certain forms of microbiological contaminants although other types of very tight filtration might work as well. Coconut shell carbon is becoming popular not only because it is made from a renewable resource but also because it produces very good tasting water and is particularly good at trihalomethane removal. A new specialty carbon called catalytic carbon is now available that will remove hydrogen sulfide gas (which produces the “rotten egg” smell in some well water) and is very good at removing chloramines (the mixture of ammonia and chlorine used as a disinfectant by some water supplies) [1]. The adsorption behavior for the coconut coal is ascribed to its high inorganic matter content (up to 13.7% wt.)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

MATERIALS and METHODS Samples Drinking water sample was taken for analysis. Drinking water was filtered through carbon block filter and samples were taken for analysis after 1, 10, 20, 30 and 40 L were filtered. Analytical methods The parameters for the drinking water were set according to the Slovenian regulation [2]. Coliform Bacteria were determined by the MPN method after APHA standard [3]. Table 1: Standard methods

Parameter

Unit

Standard method

pH

-

DIN 38 404 – C5 (1984)

Conductivity

μS/cm

EN (DIN) 27 888 (1993)

Turbidity

NTU

DIN 38 404 (1985)

Hardness

˚dH

DIN 38 409 – H6 (1986)

Pb

μg/L

DIN 38406-E 22 ICP-MS

Atrazine

μg/L

modified spectrofotometric method

Potassium

mg/L

DIN 38406-E13, AES

Nitrate

mg/L

DIN 38 405 – D19 (1988)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Rapid test WS–425B was used for determining: E.coli bakteria, Pb, pesticide (atrazine / simazine), nitrate and nitrite. Carbon block filter The filtration process begins with water passing through a graded density 5-micron prefilter that traps dirt, sand, and particles that affect the taste, odor, and overall appearance of your water. Then the water passes through the highly compacted solid carbon block where direct mechanical interception of particles as small as 0.5 micron occurs. The graded density prefilter acquires a positive molecular charge as water passes through it. Since most colloidal contaminants exhibit a negative charge in solution, the media fibers will electrokinetically attract charged colloidal particles which are smaller and removal by mechanical straining is not effective. RESULTS The results of water analyses is presented in Table 2 after 10 L of water was filtered. It is seen that all parameters masured were below the detection limits, but also pure drinking was was of best quality. Several times the analyses were repeated for treated samples (after 1, 10, 20, 30 and 40 L of water was filtered) determining pH, conductivity, turbidity and K- concentration. Results are presented in Table 3. As seen from Table 3 pH was stable, conductivity increased every time as well as turbidity til the last sample. Potasium concentration increased very much after 1 L was filtered. Also after 10 L was filtered the concentration was still very high, then it started to decrease. Lead was measured with more sufisitcated apparatus and it was found put that the concentration decreased from 3 to 1 ug/L. Some authors reported that 26 mg of lead per g of activated carbon could be adsorbed [4]. Table 2: Characteristics of the treated water Parameters

Drinking water

After treatment

cNO3

< 0,5 mg/L

< 0,5 mg/L

cNO2

< 0,01 mg/L

< 0,01 mg/L

cE.coli

negative

negative

cPb

< 15 µg/L

< 15 µg/L

catrazine

< 3 µg/L

< 3 µg/L

csimazine

< 4 µg/L

< 4 µg/L

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Table 3: Analyses before and after filtration Samples

pH

after

Conduct.

after

(uS/cm)

Tb

after

cK (mg/L)

after

(NTU)

1

7,4

7,4

518

526

0,60

0,64

3,1

48

2

7,6

7,6

522

529

0,38

0,39

3,1

20

3

7,6

7,6

530

537

0,55

0,60

3,0

4

4

7,7

7,7

545

547

0,43

0,53

3,0

3,5

5

7,6

7,6

530

530

0,32

0,32

3,0

3

Bacteria were determined on agar-agar at room temperature, 24 h. Figure 2 presents both samples of drinking water before and after treatement. As seen from Fig 2. The MPN-value (most probable number) is below 100, therefore there were no bacteria developing at room temperature.

Figure 2: MPN in drinking water (left side) and filtered water (right side) Analyses of atrazine showed that the concentration in drinking water decreased from 0,15 µg/L to 0,07 µg/L and in the second experiment from 0,15µg/L to 0,03 µg/L. Atrazine was adsorbed onto block carbon. It is in accordance with other authors who found out that coconut shell carbon is a good adsorbent for atrazine [5]. Probably some other pesticides would adsorbe even better due to the fact that higher adsorption coeficient were determined for certain pesticides as follows from Table 4.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Table 4: Freundlich constants for atrazine, desethylatrazine and metolachlor [5]. Compound

Kf

1/n

Qe (mg/g)

c (mg/L)

Atrazine

0,8

0,8

0,1

0,1

Metolachlor

115

0,4

86,6

0,5

Desethylatrazine

0,7

0,8

0,2

0,2

CONCLUSION Carbon block filter provide efficient filtration performance. Atrazine, lead and bacteria were removed from drinking water. The effectiveness is connected with good maintainance of the filter. If properly mantained the filter could be effective for years in 4- member family housekeeping. The total hardness in water was lower at the start. After about 10 L of water was filtered, the hardness of water increased near value of safe drinking water. The concentration of K+ in water was very high at the start of filtration. After around 20 L were filtered, K+ concentration was reduced down to 4 mg/L. The concentrations of atrazine and lead in water samples were reduced after being treated with filter.

LIST OF REFERENCES [1] Coconut shell drinking water treatment (2011). Filtration + Separation, 48 2, p. 12 [2] Official Gazette of the Republic of Slovenia. Regulation on drinking water, No 19, 2004. [3] APHA (1990). Standard Methods for the Examination of Water and Wastewater, Drinking Water Microbiology. [4] M. Sekara, V. Sakthia and S. Rengaraj (2004). Kinetics and equilibrium adsorption study of lead (II) onto activated carbon prepared from coconut shell, Journal of Colloid and Interface Science, 279/2, S307–S313. [5] B. Tepuš (2007). Simultanous atrazine and nitrate removal by catalitical ozonation and ion exchange, Doctoral thesis, University of Maribor.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

BIOGÁZ Galbács Zoltán, Gyulai Tamás Délalföld Fenntartható Környezetéért Alapítvány Email: [email protected]

Előzmények A biogáz fő komponense a metán (CH4). Ennek termelését a mikroorganizmusai kezdték el még akkor, amikor a Föld oxigéntartalmú alakult ki. Ezek a metánt képező (metanogén) baktériumok a legelső Minden szerves anyagból metánt képeznek oxigéntől és fénytől Munkálkodásuk eredményei: • • • • • • •

Föld legrégebbi légköre még nem (ősi) szervezetek. elzárt közegben.

Az óceánok, tengerek partok menti régióiban hatalmas mennyiségű metán található a mélyben vízzel képezett ún. klatrátok (hidrátok) formájában. Metánt rejtenek a mindig fagyott talajok (Pl. a sarkkörön túli területeken). Bármely talajvizet vizsgálva, benne oldott metánt találunk. Az artézi kutak vize mindig metánt tartalmaz, olykor olyan magas koncentrációban, hogy az ivóvizet kezelés nélkül tűz- és robbanásveszélyesnek kell tekinteni. A kőszénrétegek bányászatakor a rétegekbe zárt metán kiszabadulva és levegővel keveredve ún. sújtólég-robbanást okoz, még manapság is. A földgázok túlnyomórészt metánt tartalmaznak. Az üledékes rétegekbe zárva nagy mennyiségű metán halmozódott fel. (Pl. Magyarországon a Makói árokban.)

A metán, ha a levegőbe jut, a szén-dioxidnál sokkal nagyobb mértékben járul hozzá a Föld globális fölmelegedéséhez, a napfény hőenergiájának visszatartásához, mint a szén-dioxid. (A metán a szén-dioxidnál kb. 25-ször nagyobb mértékben tartja vissza a hősugarakat.) Ezért a levegőbe jutó és a szén-dioxidnál kevesebb metán is jelentős veszélyt jelent. (Az emberi tevékenységért felelős üvegházhatás kb. 20%-át a metán okozza.) Amióta az emberiség a „fejlődés” során egyre nagyobb mértékben veszi igénybe az energia forrásokat, a Föld erőforrásait, ásványkincseit, egyre nagyobb arányban kerül metán a légkörbe: • • •

Az ivóvíz szolgáltatásnál épp a tűz- és robbanásveszélyesség miatt a vizek metántartalmát elszellőzik, s az így a légkörbe jut. A szénbányászatban ugyancsak szellőztetéssel juttatják a levegőbe a rétegből kiszabadult metánt. A földgáz kitermelése, feldolgozása, továbbítása során a metán egy része „elszökik” és a légkörbe kerül.

A metanogén baktériumok igen különböző körülmények között (de oxigéntől elzárva, anaerob módon) léteznek, működnek. Amíg oxigén van jelen, szüneteltetik a működésüket. Az egész

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Földön elterjedtek. Ha nem steril körülmények között levegőtől elzáródva található szerves anyag, megindul a tevékenységük: • •

• • • • •

Az egyik legjobb példa a biogáz képződésre a szarvasmarhák emésztő rendszere. A mocsaras vidékeken az üledékben lejátszódó metánképződés a vízen látható buborékolást eredményez. Erről, az így felszabaduló metánról, amely buborékolást az iszap bolygatásával (pl. bottal felkeverve az iszapot) jobban láthatóvá tehetünk, mocsárgáznak is nevezik a metánt. A hatalmas területű rizsföldeken igen tetemes mennyiségű metán képződik és kerül a légkörbe. A szeméttelepek egymásra halmozott szerves (pl. konyhai) hulladékából ugyancsak metán képződik. A szennyvíz csatornák zárt világában is fejlődik metán. A trágyadombok belsejében képződő metán a hagyományos trágyaérlelés során részben a levegőbe kerül. A mezőgazdaságban a betakarítást követően beszántott növényi maradványokból, trágyából képződik metán. (Hasonló a folyamat a kertek talajába ásott szerves anyag esetében is.) Színhelyek és tevékenységek Állattenyésztés Mocsarak, lápok Rizsföldek Biomassza égetés Termeszek Szeméttelepek Tengerek, édesvizek Hidrátzárványok Széntermelés Földgáz és kőolajtermelés Gázszivárgás Összesen

A Föld becsült metán termelése, Tg/év 80 142 577 55 44 62 85 10 35 10 48 1148

Épp azért, mert a metán számottevően járulhat hozzá a globális felmelegedéshez, az emberiségnek elemi érdeke az, hogy a lehető legnagyobb mértékben gátolja meg a metán levegőbe kerülését. Ha lehet, akkor a képződött metánt (ha más hasznosítást nem talál), legalább égesse el. Ekkor a metánból azonos mól-számú szén-dioxid képződik (pl. l mólnyi metánból l mólnyi szén-dioxid lesz az égetés eredményeként). Mivel a szén-dioxid napsugárzást visszatartó ereje csak l/25-öd része a metánénak, így jelentősen mérsékelhető lenne a metán globális-felmelegedést okozó veszélyessége. Vannak, akik a globális felmelegedés esetleges katasztrofális hatását a metánnal hozzák kapcsolatba. Egyesek úgy érvelnek, hogy ha az emberiség nem fogja vissza a szén-dioxid kibocsátást, és a földi átlagos hőmérséklet több fokkal emelkedik, akkor az eddig „fogva tartott” metán is a levegőbe kerül. Ha az örökké fagyott talajok (pl. Szibériában) is felmelegednek, kiolvadnak, akkor a talajban lévő metán kiszabadul. Ez a hatalmas mennyiség a levegőbe jutva további melegedést eredményez. Ennek hatására esetleg a tengervízben (a fenéken) található klatrátok (metán-hidrátok) is elbomlanak ( az emelkedő hőmérséklet miatt)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

és azokból újabb hő-csapdázó metán kerülhet a légkörbe. Az öngerjesztő folyamatok során az egyre gyorsuló melegedés az emberiségre katasztrofális hatást fejt ki. Ökológiai katasztrófa következhet. Mindezek elkerülése érdekében az emberiségnek meg kell fékezni (más most) a globális felmelegedést! A természet kialakította a maga globális egyensúlyát (amíg az emberiség nagy mértékben nem módosította azt). Ugyancsak az ősidőkben, a metánt képező baktériumok után megjelentek az ún. „metánfaló” (metánt oxidáló, metanotróf) baktériumok, amelyek a metánt oxigén jelenlétében szén-dioxiddá oxidálják. Ugyancsak elterjedtek, sokfélék. Működésük miatt van az, hogy a pohárba kitöltött artézi víz, talajvíz, amely frissen kitöltve metán tartalmú, néhány nap múlva teljesen elveszíti metántartalmát. Ezért van az, hogy a folyóvíz sem tartalmaz metánt, ha a víz kellő hullámzása bőségesen juttat oxigént a vízbe.(Épp a metánfaló baktériumok miatt kell a metántartalmú vizek analitikai eljárásánál különös gonddal eljárni, és a minta tárolásánál levegőmentességre kell törekedni, vagy baktériumölő vegyszereket kell alkalmazni. Ha rétegvízben nem található metán, akkor az analitikai módszer a hibás!) Néhány metánt képező baktérium Methanobacterium propionicum Methanobacterium suboxydans Methanobacterium ruminatium Methanobacterium formicium Methanobacterium omelianskii Methanobacterium soehngenii Methanococcus vaniellii Methanococcus mazei Methanosarcina barkeri Methanosarcina methanica

Néhány metanotróf baktérium Bacillus methanicus Methanomonas methanooxidans Methylococcus capsulatus Methylococcus thermophilus Methylosinus sporium Methylosinus trichosporium Methylobacter albus Methylobacter marinus Methylomonas aurantiaca Methylocystis parvus

A metánfaló baktériumok miatt a természetben képződő metánnak „csak” kb. 30-40 %-a kerül a légkörbe: Pl. Amikor a talajba szántják a tarlót vagy trágyát, a hónapok során képződő metán igyekszik a talaj hézagain keresztül a felszínre kerülni. A levegőnél kisebb sűrűségű metán gáz, amint felfelé diffundál, olyan rétegeken halad át, amelyekbe a levegőből oxigén diffundált. Itt, a megélő metánfaló baktériumok a metán nagyobb részét oxidálják. A bolygatatlan természetben kialakulhat valamiféle egyensúly, de a növekvő népesség számára szükséges élelmiszertermelés több rizsföldet, intenzívebb mezőgazdaságot, következésképp több légköri metánt eredményez. Mai ésszel gondolkodva, az volna érdekünk, hogy minél több zárt terű metánképződést alakítsunk ki. (Egyesek már a marhahús és tejtermékek fogyasztásának visszaszorítását vélik indokoltnak, vegetáriánus életmódot javasolnak!) A biogáz képződést több száz éve ismeri az emberiség. A mocsárgázt SHIRLEY fedezte fel 1667-ben. Felismerték, hogy növényi maradványokból képződik (VOLTA 1776-ban) a mocsárgáz. Először DALTON analizálta a metángázt 1804-ben. PASTEUR felismerte, hogy mikroorganizmusok tevékenységének produktuma. DAVY almos istállótrágyával kísérletezve biogázt fejlesztett 1808-ban. Viszonylag hamar építettek biogáz fejlesztő telepet (Montungában, Bombay közelében egy lepratelepen 1856-ban).

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Kezdetben nem az ökológiai katasztrófa elkerülése érdekében kezdtek biogáz fejlesztésbe! Olyan területeken, ahol a szegénység miatt nem volt egyhamar remélhető, hogy cső távvezetéken oda szállítják majd a gázt (az energiát), maguk igyekeztek tenni. Volt munkaerő és volt állattartás. A néhány állatot tartó farmokon az állati trágyát földbe vájt üregben biogáz fejlesztésre fogták, amit a farmok szomszédos épületében főzéshez, világításhoz felhasználtak. Épp a legszegényebb országokban építették a legtöbb biogáz fejlesztőt. Ma a világon hozzávetőleg 10 millió biogáz fejlesztő működhet. A fejlett világ kezdetben alig mutatott érdeklődést a biogáz fejlesztés iránt. Az acél-beton fejlesztő építmények költségesnek bizonyultak. Az olcsó földgáz nem motivált a biogáz fejlesztés irányába. Leszámítva a háborús körülményeket, majd az energiaválság (olajár robbanás) időszakait, alig nőtt a fejlett világ érdeklődése a biogáz iránt. Az újabb körülmények segítettek a biogáz technológiák fejlesztésében: • • • • •

Kiderült, hogy végesek az eddigi energiaforrások, kellenek a megújulók. (Hamarosan elfogy a kőolaj, jobb volna azt inkább szintetikus célokra tartalékolni.) A fejlesztésekhez az országok (EU) jelentős összegeket ajánlottak fel. A profitorientált állattartás a környezetet bűzhatásával ingerli, valamit tenni kell. A környezetbe jutó szennyezések mértéke nő, és a veszélyesség miatt lehet, hogy a hatóságok betiltják (nem engedélyezik) az állattartást. A büntetések (bírságok, pl. csatornabírság) mértéke nő, közelít a biogáz fejlesztés beruházási költségéhez.

Ha a befektetőket az emberiség miatti aggodalom kevéssé motiválja is, de a remélhető profit újabban mégiscsak felkeltette a biogáz iránti érdeklődést.

Lehetőségek A biogáz előállítása minden élő szervezet által létrehozott szerves vegyületből lehetséges. A biogáz (metán) fejlesztés többféle mikroorganizmus együttes tevékenységének eredménye. Egyik korlátozó tényező, hogy a lignintartalmú anyagokat nehezen tudják lebontani, ezért a fás anyagok kevéssé alkalmasak metángyártás céljára. (Azokat lehet brikettálni, vagy pelletté alakítva tüzelhetik el.) Elvben lehetséges volna kizárólag a metán termelése érdekében termesztett lágyszárú növényekből, mint alapanyagból kiindulni. Józan ésszel belátható azonban, hogy a termőföldeknek elsősorban az élelmiszer előállítást kell szolgálniuk. Már a bioetanol és biodízel programok túlhajszolásakor belátható volt, hogy az üzemanyagok „termesztése”, ahogy visszaszorítja az élelmiszer termelést, úgy drágítja az élelmiszereket és éhséglázadásokhoz vezet. Célszerűnek látszik csupán az élelmiszerként nem használható hulladékokból, melléktermékekből biogázt fejleszteni. Az alábbi táblázatból (a néhány példából) látható, mily sokféle alapanyag áll rendelkezésre.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Biogáz fejlesztés lehetséges alapanyagai Csatornaiszap Disznóürülék Baromfitrágya Szarvasmarha trágya Földimogyoróhéj Növényi magvak Lótrágya Birkaürülék Istállótrágya Napraforgólevél Takarmány cukorrépalevél Istállótrágya Búzaszalma Rozsszalma Árpaszalma Zabszalma Repceszalma Zöldségmaradékok Burgonyaszár Cukornádszál Rizsszalma Len Kender Fű Elefántfű

Az 1 kg szárazanyagból fejleszthető metán m3/kg 0,520 0,440 0,460 0,200 0,360 0,620 0,250 0,200 0,225 0,300 0,450 0,230 0,250 0,250 0,280 0,300 0,200 0,345 0,380 0,170 0,230 0,360 0,360 0,410 0,500

Természetesen a táblázat felsorolása nem teljes, más hulladékok, fehérje-, szénhidrát- és zsírtartalmú anyagok is fejlesztésbe vonhatók. Feltűnő lehet, hogy a táblázatban kevesebb metánfejlődést találnak, mint amennyi az alapanyag széntartalma alapján remélhető lenne. A valóságban nem lehetséges a teljes széntartalmat metánná alakítani. Elméletileg sem lehetséges. Meg kell elégedni azzal, hogy a széntartalom fele vagy harmada alakul át metánná. Ez tulajdonképp előnyös. A kiindulási anyag nagyobb molekuláit a bontó mikroorganizmusok sokkal kisebb vegyületekké alakítják. Ami nem konvertálódik metánná, az megreked a kismolekulájú szerves vegyületek formájában. A növények ezeket a kisebb vegyületeket jobban, hatékonyabban és könnyebben fel tudják venni. A biogáz fejlesztésnek nem is a metán a fő értéke, hanem a visszamaradt értékes trágya, amely nagyobb termést eredményez, mint a hagyományos- vagy műtrágyák! Hazánkban a növénytermesztésből kb. 8 millió tonna melléktermék áll rendelkezésre évente. Az állattenyésztés mellékterméke (az almos és hígtrágya) hozzávetőleg ugyanennyi (7-8 millió tonna). Hozzávéve az élelmiszeripar hulladékait valamint a települési hulladékokat is, évente kb. 900 PJ energia volna előállítható (metánon keresztül), amely kb. 100 G/ha potenciális lehetőséget jelent. (Évente néhány millió tonna olaj eltüzelése volna megtakarítható!)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Az ország területének legnagyobb része mezőgazdaságilag művelt. Így a melléktermékek eloszlása közel egyenletesnek vehető. A hulladékokat részint higiéniai okok miatt (a trágyáknál), másrészt a hulladékok kis sűrűsége miatt (pl. a kis térfogatsúlyú szalmánál) nem célszerű, nem gazdaságos messzire szállítani. A biogáz fejlesztés eredményét, a kierjesztett maradékot, az értékes bioenergia pótló trágyát is célszerűbb (gazdaságosabb) helyben felhasználni. Ezekből az következik, hogy a biogáz fejlesztőkből sok kisebbet, mintsem néhány nagyobbat célszerű építeni. Akkora területet kell kiszolgálnia, amely legfeljebb kb. 20-25 km távolságra van. Esetleg oda kell telepíteni, ahol nagyobb számú állatot tenyésztenek, s a trágya nagy tömegben rendelkezésre áll.

Befolyásoló tényezők A C/N arány A biogáz fejlesztésnél közreműködő mikroorganizmusok működésükhöz a környezetből tápanyagokat vesznek fel, testüket is építik, szaporodnak. Szükséges az ütemes működéshez a nitrogén forrás is. Tapasztalat szerint az a legjobb, ha a biogáz alapanyagban a szén és nitrogén aránya kb. 20-30. (C/N ~30). Ez nem jelenti azt, hogy a C/N ~3 arányú hulladékban nincs metángáz fejlődés, csak a fejlődés lassúbb. Célszerű ezért, ha többféle hulladék is rendelkezésre áll, a hulladékokat vegyesen, összekeverve adagolni, lehető legjobban megközelítve az optimális C/N arányt. Közel ideális a kommunális hulladékok C/N aránya. Az egyes mezőgazdasági hulladékok atomaránya igen különböző lehet: Alapanyag (szerves anyag) Vágóhídi hulladék Élelmiszeripari hulladék, alga Marha-, csirke- és sertéstrágya Széna,fű, zöldségfélék Háztartási (konyhai) hulladék Szalma Fa, fűrészpor

C/N arány 2-4 5-10 5-10 10-20 30-40 50-150 200-500

Jobb hatásfokú fejlesztés érhető el vegyes hulladékokkal. Gyakorlatban bevált keverési módokat mutat a következő két táblázat: Adagolt anyag

A keverék aránya %

Marhatrágya Sertéstrágya Baromfitrágya Szennyvíziszap Gyomnövények Marhatrágya+sertéstrágya Marhatrágya+baromfitrágya Marhatrágya+szennyvíziszap Sertés-, marha-és baromfitrágya együtt Szennyvíziszap+gyomnövények

50+50 50+50 50+50 50+25+25 50+50

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40 nap alatt nyerhető biogáz 3 m /kg szerves anyag 0,380 0,570 0,620 0,270 0,280 0,510 0,528 0,407 0,585 0,387

The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

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Gázhozam 100 nap alatt 3 m /kg szerves anyag 0,328

Gázhozam 100 nap alatt 3 m /kg szárazanyag 0,281

82 94 89 82

0,160 0,266 0,529 0,341

0,131 0,155 0,370 0,290

82

0,245

0,181

82 82

0,120 0,227

0,102 0,185

Hulladék

Víztartalom %

Szarvasmarha istállótrágya Sertés szilád ürülék Híg fekália Szennyvíziszap Nádhulladék+szennyvíziszap Rizspelyva+szennyvíziszap Szőlőtörköly Szőlőtörköly+szennyvíziszap

A hőmérséklet hatása Biogáz fejlesztő mikroorganizmusokat egyaránt találtak gleccserek vizében és hőforrásokban is. Ez azt jelenti, hogy +4 ºC és 70 ºC (90 ºC ?) tartományban egyaránt lehetséges a biogáz fejlesztés. Természetesen az eltérő hőmérsékleten más-más mikroorganizmusok érzik magukat jól, működnek és szaporodnak. Ha a közeg hőmérséklete megváltozik, akkor véglegesen nem szűnik meg gázfejlődés, hanem idő kell, míg lassan felszaporodnak azok a baktériumok, melyek a megváltozott hőmérsékletet kedvelik. A biogáz fejlesztés szempontjából az a jó, ha állandó a hőmérséklet. Ezt vagy úgy érik el, hogy az erjesztő reaktort a földbe süllyesztik (a talajhőmérséklet közel állandó), vagy a fejlesztett biogáz egy részével állandóan melegítik a fermentort (akár a biogáz 30%-át is erre használva), és még az erjesztő tartályt kívülről valamiképp hőszigetelik is. A hőmérséklet a gázfejlődés (és minden részfolyamat) sebességét is befolyásolja. Minél magasabb a hőmérséklet, annál nagyobb a gázfejlődés sebessége (és a kémiai reakciók sebessége is általában). Ebből az következne, hogy lehető legmagasabb hőmérsékleten kellene járatni a bioreaktort. Mégsem ez a gyakori, mert a magasabb hőmérsékleten tartáshoz több energia kell, jobban kell fűteni és hőt szigetelni. A fejlett világban leggyakrabban ún. mezofil eljárásokat működtetnek (30-35 ºC). Ritkábbak a pszichrofil eljárások (~15 ºC) és termofil eljárások (~54 ºC). A legnagyobb számú biofejlesztő a fejlődő (szegény) országokban működik, ahol talajba süllyesztett vagy környezeti hőmérsékletű (nem mesterségesen fűtött) rendszereket építettek. Az alkalmazott hőmérsékletnek további járulékos hatása a fertőtlenítés. Az esetlegesen fertőző kórokozókat, gyom magvakat a magasabb hőmérsékleten működtetett biogáz fejlesztő hamarabb, nagyobb arányban elöli.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Az idő tényező A feltöltött és anaerob módon lezárt biogáz fejlesztő gáztermelése az időben egy gázkromatogram kirajzolódásához hasonló (tranziens jel szerű) változást mutat: 1. Kezdetben lassan növekszik a gáztermelés (mert idő kell, míg elszaporodnak a mikroorganizmusok, másrészt az alapanyag részleges lebomlásának (a savas erjedésnek) kell előbb végbemenni, hogy ezt követően a második lépésben a metántermelés is megindulhasson. 2. Amikor már bőséges a fejlődés, a görbe menete (a gázfejődés sebessége—idő függvényen) eléri a maximumát, s majd lassan csökkenő menetet mutat. Ez szükségszerű, mert ahogy fogy az alapanyag, úgy csökken a metántermelés sebessége is. 3. A maximum görbe leszálló ága egyre kisebb meredekséggel még sokáig tart. Ez az ún. „farok” rész hosszan elnyúló. Ha az eltelt időt az indulástól kezdve mérjük, akkor a maximális gázfejlődésig (sebességig) eltelt időnek többszöröse (akár 5-10-szerese is) lehet az az idő, míg gyakorlatilag megszűnőnek vehetjük a gázfejlődést. Ha a bioreaktorban hosszú időt biztosítunk a gázfejlődéshez (azért, hogy minél nagyobb térfogatú biogázt foghassunk fel), akkor a fermentor tartályt nagy térfogatúra kell választani (amely költséges beruházás). Ha megelégszünk a „farok” nélküli gáztermeléssel, akkor kisebb fermentor tartály is elég, de ez esetben elvész a maradék metán. A pH hatása A biogáz fejlesztőben lejátszó folyamatok rendkívül összetettek. hidrolízise játszódik le (baktériumok, enzimek közreműködésével) csökken a pH. (Ez az ún. 1. szakasz, fokozat). Ezt követően játszódik szakasz, fokozat). A hulladék komponensei, a szénhidrátok, zsírok lebomlanak:

Először a hulladék és savképzés miatt le metánképződés (2. és fehérjék egyaránt

A szénhidrátokból etilalkohol, propilalkohol, butilalkohol, hangyasav, ecetsav, propionsav, vajsav, tejsav, borostyánkősav, szén-dioxid, hidrogén, stb. fejődik az első fokozatban. A zsírokból glicerin, hangyasav, ecetsav, propionsav, vajsav, tejsav, borostyánkősav, etilalkohol, butilalkohol, szén-dioxid, hidrogén, stb. fejlődik az első fokozatban. A fehérjékből aminosavak, rövid láncú peptidek, ammónia, stb. fejlődnek kezdetben. Amint látható, sokféle sav keletkezik az első fokozatban. A savas közeg, alacsony pH nem kedvez a metanogén baktériumoknak és a metánfejlődés a pH-csökkenés miatt lelassul. A szerves hulladék ütemes adagolásával, esetleg a savakat semlegesítő adalék (oltott mész, magnézium-oxid, stb.) adagolásával ajánlatos elérni, hogy az erjesztőben ne alakulhasson ki alacsony pH. Ha a pH az optimálisnál nagyobb (mert a képződő ammónia lúgosítja a vizes közeget), akkor a fehérje bomlásából képződő ammónia nagyobb arányban lesz jelen nem ionos (tehát semleges NH3) formában, amely gátolja a metánt képező baktériumok működését. A legfontosabb tehát a pH-követése és ha szükséges, annak módosítása az optimális pH~7,5 közelébe.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

A víz hatása A biogáz fejlesztőben szükséges, hogy a baktériumok könnyen megtalálják a táplálékot, a mikro-mozgásokra legyen lehetőség, azaz a közeg víztartalma kellőn magas legyen (80-95%). Ha nagyon sok a víz, akkor a kevés szerves anyagból csak kevés metán fejlődhet. Ha kevés a víz és sok a szerves anyag, akkor a mozgásgátlás miatt lesz kisebb a mikroorganizmusok aktivitása. Amíg a híg trágya fermentációja vizes közegben végbemegy néhány hónap alatt, addig a háztartási hulladékokat szárazon felhalmozva a szeméttelepen, s lezárva, a „dombban” a biogáz (depóniagáz) fejlődés évtizedekig is eltarthat. A hígabb, híg zagy jellegű masszát könnyebb mozgatni, szivattyúzni is. A spontán keveredés is könnyebb, amikor a fejlődött gázbuborékok egy diszpergált hulladékdarabkára tapadva lifteznek felfelé, s közben mozgatják a közeget. Ha az alapanyag sűrű, akkor extra vízzel kell beállítani a sűrűséget. (A híg trágyánál inkább szilárd anyagot kell adagolni.). A víz lehet folyóvíz, talajvíz és artézi víz. Az adottság lehet különböző, de a legjobb a folyóvíz, mert abban a legkisebb az ásványi anyag tartalom. Ekkor a kierjedt massza maradékát biztonsággal ki lehet juttatni a környező földekre. Minél kisebb a víz nátriumion tartalma, annál kisebb a szikesedés veszélye. (Ezért is előnyösebb a folyóvíz.) Állattartó telepeket kiszolgáló biogáz fejlesztőknél ügyelni kell arra, hogy a hígtrágyába lehetőleg ne jusson tisztítószer, antibiotikum vagy fertőtlenítő szer maradéka, vízzel sem. (Az irodalomban adatokat találunk arra, hogy egyes szerek, hatóanyagok (pl. Bacitracin, Flavomycin, Lasalocid, Monensin,Spiramycin, Tysolin, Virginiamycin, Arzanilsav, Furazolidon, Sulfamethazin, Olaquindox, Kloroform, fenolok, aldehidek, stb.) akár 90%-os csökkenést eredményezhetnek a biogáz termelésben.) Különösen a nagyobb állattartó telepek állományának egyidejű oltása, fertőtlenítése során lehet számottevő a trágyába kerülő szennyezés. Alapanyag előkezelése A jobb behatás eléréséhez szükséges az alapanyag minél apróbb részletre való darabolása (foszlatása). Ha ezt a különböző hulladékok előzetes összekeverését követően végezzük, akkor egyúttal a bioreaktorba kerülő anyag homogén eloszlatását is elérjük (ami feltétele az ütemes biogáz fejlődésnek). Minél apróbb részletű az alapanyag, annál gyorsabb biogáz fejlődést remélhetünk. Keverés A biogáz fejlesztőben található masszát csupán csak a jobb hőátadás érdekében szükséges naponta átkeverni.(A fermentorba épített hőcserélő csövek környezetéből az átmelegedett rétegeket távolabbra juttatjuk, biztosítva a hidegebb részeknek is a felmelegedést.) Esetleg a „filcesedést”, a nem kellően feldarabolt hulladékból a reaktorban összetapadt réteget kell szétmozgatni. Semmiképp sem szabad állandó (és intenzív) keverést alkalmazni! A különböző mikroorganizmusok egymáshoz tapadva (érintkezve) végzik az atom és töltéscserét. Ha

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

keveréssel szét választanánk azokat, akkor lecsökkenne a gázfejődés (a hidrogén átvitel gátlás következtében).

Technológiák A Föld országaiban igen különböző, sokféle biogáz fejlesztő megoldás, technológia működik. Szerencsére a világpiacon változatos kivitelű berendezés kapható, kulcsrakész beruházásként is. Sok irodalomból, könyvekből sajátíthatók el a fogások, kiviteli megoldások. Mindenek előtt szükséges, hogy a leendő alkalmazó legyen tisztában a rendelkezésére álló hulladék mennyiségével, és azzal, milyen célt kíván elérni a biogáz fejlesztéssel. Néhány szempont a döntéshez: •







• • • •

Ha legolcsóbban szeretne megvalósítani, akkor a lehető legnagyobb arányban kell igénybe venni a már meglévő építményeket, műtárgyakat, s csupán a hiányzók beszerzése szükséges. (Beton silók, tározók, könnyen lezárhatók az anaerob erjesztéshez. Ennek térfogata, aránya a hulladék mennyiséghez megszabja az erjesztés sebességét, az alkalmazható hőmérsékletet, stb.) Saját erővel kivitelezett létesítmények a legolcsóbbak. Több mint 9 millió minta (példa) található a legszegényebb országokban. Ha gyógyszeripari alapanyagok előállítása a cél, akkor válogatott (tiszta, ürüléket nem tartalmazó) növényi anyagot kell fermentálni sztatikus módon.(Beadagolást követően lezárják a fermentort és kivárják a fejlesztés végét.) Nem fontos az időigény. Több haszon van a gyógyszer alapanyagon, a visszamaradt masszán, mint a biogázon. Ha híg trágyát kell ártalmatlanítani, mert bűzével szennyezi a környéket, akkor áramlásos technológiát kell választani, ahol ütemesen, kvázi folyamatosan lehet beadagolni. Minél hamarabb kerüljön be a híg trágya a fermentorba, a zárt rendszerbe, hogy a bűze ne terjedjen. Olyan hosszú tartózkodási időt kell biztosítani, hogy a kikerült maradék bűze már ne legyen jelentős. Ennél a technológiánál számolni kell azzal, hogy a fermentor után kell utóérlelő tartály (medence), ahol még kellő ideig tartózkodhat a maradék, hogy a patogén kórokozók száma minél nagyobb arányban csökkenjen le. Számolni kell azzal is, hogy a kierjesztett maradék mezőgazdasági területen csak előírások (trágyarendelet) szerint juttatható a talajba! Természetesen mindenféle trágya bontható sztatikusan is, ami azt jelenti, hogy egyszer feltöltik a fejlesztőt, és lezárják. Ez jobb, mert nagyobb arányban pusztulnak el a káros mikroorganizmusok. Nem fordulhat elő az, amely áramlásos rendszernél nem kizárható, hogy a friss trágya hozzákerül a „kész”, kierjedt maradékhoz és úgy kerül a földekre, esetleg fertőzően! Ha kényszerítő körülmény a gyors működtetés, akkor fűtött biogáz fejlesztő tartályt kell beépíteni. Ha fontos a legnagyobb metán kihozatal, akkor fűtött, sztatikus rendszert kell választani. Ha „csupán” a globális felmelegedés mérséklése a fontos, akkor sztatikus és fűtött reaktor tér a jó megoldás. Ha nincs sok kézi munkaerő, akkor a folyamatos, automatizált megoldások között kell válogatni.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Termékek, haszon A biogáz fő komponense a metán (kb. 50-70%), a maradék főképp szén-dioxid (kb. 50-30%). E mellett a fejlesztés hőmérsékletén telített vízgőz van benne, és még kis mennyiségben kénhidrogént (H2S) és ammóniát (NH3) tartalmazhat szennyezésként. Az egyéb anyagok esetlegesek (pl. depóniagázban szilán származék), és kis koncentrációjúak. Összehasonlításként néhány metántartalmú gáz néhány jellemzője: Jellemző Szénhidrogén (CH4) tartalom, % CO2 ,% Nitrogén,% Egyéb gázok % Fűtőérték, MJ/Nm3 Sűrűség (15 ºC-on), kg/m3 Robbanási határkoncentráció, % Oktánszám

Földgáz

Biogáz

94-98 0,0-3 0,3-4 0,0-0,2 32-40 0,8-0,9 5-15 120-130

50-70 27-42 0-1 0-3 18-25 1,10-1,15

Szeméttelep depóniagáza 45-55 30-35 15-25 0-3 15-17 1,15-1,20 9-23 105-120

A biogáz sokkal kevésbé tűzveszélyes, mint a tiszta metán, a földgáz. A metán levegővel keveredve, ha 5-15% arányban van jelen, akkor robbanó elegyet képez. Szikra hatására robban (pl. sujtólég robbanás a szénbányában!) Ezzel szemben, noha kb. tízmillió biogáz fejlesztő működik már , a biogázzal kapcsolatos robbanások, balesetek nem ismeretesek. A lomha viselkedés oka a szén-dioxid magas koncentrációja. Ez nem jelenti azt, hogy nem kell vigyázni. A belsőégésű motorokba (gázmotorba) vezetve igenis robban! Csupán a vízgőzt célszerű leválasztani ahhoz, hogy tüzeléshez, világításhoz a biogáz jól felhasználható legyen. Ennek legegyszerűbb módja a talajba fektetett csöveken való átvezetés és a hidegebb talaj-környezetben kivált cseppfolyós kondenzvíz leválasztása. Alkalmas a biogáz az ún. külső égésű motorok működtetésére. Ezeknél, mint pl. a Stirling motoroknál kívülről kell fűteni. Ha belső égésű motorba kívánják vezetni, akkor célszerű a szén-dioxidot előzetesen kimosni a gázból (hogy a metán %-os aránya nagyobb legyen) és kén-hidrogén-, valamint ammónia mentesíteni is szükséges. (Ez azért szükséges, mert a robbanási térben a kén-hidrogénből savas anyag képződik, az ammóniából pedig nitrogén-oxidok képződnek. Mindegyik rongálja, megmarja a motort, és a kipufogó gázzal a levegőbe kerülve környezetszennyezők!) A szén-dioxid eltávolítása legegyszerűbben vizes mosással lehetséges. Néhány bar nyomású (tehát kompresszorral összesűrített) biogázt vízzel érintkeztetik zárt térben. A széndioxid beoldódik a vízbe, miközben a metán alig oldódik. A metánból kb. l6 g oldódik 1 m3 vízben, ezzel szemben a széndioxidból kb. 800 g oldódik. Miután vízzel kimosták a szén-dioxidot, a metánra dúsabb gázt tovább viszik. A mosó vízből pedig atmoszféra nyomáson kiszellőztetik a szén-dioxidot (és sajnos, a kis mennyiségű metánt is), és újra felhasználható a víz a mosáshoz.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

A kénhidrogén mentesítés biológiai módszere is elterjedt, amelynél néhány % levegőt juttatnak a biogázba és alkalmas mikroorganizmusok oxigén jelenlétében ként (S) választanak ki. E módszer különös gondosságot igényel és néhány százalék metán elvesztésével jár. A biológiai módszernél hatékonyabb a kémiai kén-hidrogén mentesítés. Ennél pl. vas(III)-sók oldatát használják, amelyen átvezetve a biogázt, annak kén-hidrogén tartalma a vas(III)-at vas(II)-szulfiddá (FeS) redukálja és elemi kén (S) válik ki. Mindegyik kéntartalmú termék szilárd, és visszamarad. Így a gázból eltűnik a kéntartalom. Az ammónia a biogázból vízzel, esetleg savas oldaton való átvezetéssel mosható ki. (Ha van szén-dioxid kimosás, akkor az a gázfázisú ammóniát is eltávolítja.) A biogáz, ha nagy mennyiségben állítják elő, esetleg az országos gáz hálózatba is táplálható (természetesen a szén-dioxid eltávolítását követően). A biogáz sűrítve gáztartályokban alkalmas a közeli robbanómotoros munkagépek működtetésére. Mivel a metán igen nehezen cseppfolyósítható, (így nem teszik,) a tartályba kevesebb fér (mint a cseppfolyós propán-bután üzemanyagból), ezért gyakrabban kell feltölteni az üzemanyag gáztartályt. Tüzelésre a biogáz minden formájában alkalmas. Leggyakoribb a főzésre, fűtésre való használat. Gond lehet, hogy épp a nyári időszakban, amikor a legtöbb biogáz fejlődik, a melegebb időjárás miatt kisebb a fűtési igény. Helyette össze kell szervezni olyan tevékenységeket a közelben amelyek hőt vagy biogázt igényelnek: • • • • •



A fás anyagokból brikettet és pelletet lehet készíteni, azonban a darabolás-préselés előtt az anyagot szárítani kell (pl. biogáz fűtéssel). Lehet biogázzal üzemeltetni az aszfaltkeverőt, vagy vulkanizáló üzemet. Amennyiben abszorpciós hűtőgépet állítanak be, amelyet egyik oldalon melegíteni (fűteni) szükséges (pl. biogáz égetéssel), úgy hűtést (hűtőházat) lehet működtetni. Gázmotorokat+generátorokat beállítva, a biogázzal villamos energiát lehet előállítani, amit helyben lehet felhasználni, vagy a fölösleg villamos hálózatba táplálható. (pl. Szegeden a szennyvíztisztító telepen.) Egy igen figyelemre méltó lehetőséget mutatott meg Oláh György (Nobel díjas kémikus). Szerinte a kőolaj készletek kimerülése utáni világban a robbanó motorokat (autókat) metilalkohollal lehet majd üzemeltetni. A metanol cseppfolyós (hasonlóan a benzinhez), és igen sok módon előállítható. Képezhető pl. metánból, de hidrogénnel a szén-dioxidból is, valamint víz+szén, víz + szén-monoxid, stb. reakciókból kiindulva. Mivel a biogázban mind a metán, mind a szén-dioxid is megtalálható, (és még kevés vizet is tartalmaz), ezért alkalmas lehet metanol előállítására. Példaként említhető az USA Utah állama, ahol napi 30000 liter metanol lesz előállítva 250000 sertés trágyáját felhasználva, vagy az USA Ohio állama, ahol a szeméttelep depónia gáza szolgálja ki az évi 15000 tonna metanol előállítását. A biogáz az ún. üzemanyag cellák üzemanyaga is lehet, amelyben a levegő oxigénje segítségével metánból áramot fejlesztenek. (Pl. Berlin, 2004-ben létesült MCFC üzemanyag cella, szintén a városi szemétből fejlődő metánra alapozva.)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Külön említendő haszon, a higiénizálás. A bűzös melléktermékekből kevésbé bűzös trágyázásra alkalmas anyag marad vissza a biogázos erjesztés után. A maradékban nem csupán lecsökken a bűzös vegyületek koncentrációja (mert a mikroorganizmusok azokat átalakították), hanem lényegesen lecsökken a csírázó képes gyommagvak száma is. A biogázos erjesztés közben csupán a kiindulási anyag szerves vegyületeinek széntartalma kerül át a gázfázisba (a metán (CH4) és szén-dioxid (CO2) formájában) az összes többi elem és vegyület gyakorlatilag visszamarad a víztartalmú masszában. Az ammónia döntő része, a foszfortartalom, káliumtartalom, nyomelemek, stb. és a metánná át nem alakult szerves vegyületek mind alkalmasak a talajerő pótlására, a növények táplálására. A választott biogázos technológiától és még inkább az alapanyagoktól függ, hogy egy adott országban és vidéken milyen módon, mely mezőgazdasági területre lehet kijuttatni az erjesztés maradékát. Aki biogáz telepet létesít, annak az érvényes előírásokat mindenképp figyelembe kell vennie és alkalmaznia kell. (Példaként említhető az Indiában alkalmazott gyakorlat, amelyet a szerző a helyszínen megfigyelt. Ott a mezőkön csupasz kézzel gyűjtik össze a marhatrágyát, amelyet a vakolatlan vidéki házak falára kenik. A falon kiszáradó kerek korongokat arra használják, hogy egy botra (mint nyársra) szúrva, majd a földbe vájt kis árokba tolva és meggyújtva, annak hőjével főzik az ételeket. Amikor megfőtt az étel, a botot kihúzzák, a trágyadarabot eloltják és félreteszik a következő főzésig. A mi vidékünkön ez a trágyahasznosítás elképzelhetetlen. Itt előírások (rendeletek) és nem szükségek, évezredes szokások szabályoznak!) A biogázból elkülöníthető szén-dioxid tiszta, a vegyiparban, élelmiszeriparban jól hasznosítható. (Sokkal tisztább, mint pl. hőerőművek kéményén keresztül távozó széndioxid.)

Összegzés •

Klímavédelmi célból minél több, az élő szervezetek által előállított növényi és állati hulladékot, mellékterméket, maradványt biogázos erjesztésbe kellene fogni. • A metánnak szén-dioxiddá alakulását ellenőrzött módon, (ember által) szabályozva az üvegházhatást mérsékelhetjük. • A klímavédelem a legegyszerűbb megoldásokkal is elérhető. • A biogáz fejlesztés termékei, a metán, szén-dioxid és a visszamaradt massza (a kierjedt maradék) értékesíthetők. • A biogázos fejlesztés maradékával történő talajerő pótlás jobb, mint a hagyományosvagy a műtrágyázás. • A fertőtlenítés és bűzcsökkentés leggazdaságosabb módon biogázos fejlesztéssel lehetséges. • Az optimális megoldás (kivitel) a rendelkezésre álló alapanyagok minőségétől és mennyiségétől függ, de a gazdasági körülmények is befolyásolnak. • Biogáz fejlesztésnél a pH-követés a legfontosabb. • Kivitelezés előtt a bőséges szakirodalom (szak-cikkek és könyvek) tanulmányozása, egyes rendszerek termelési adatainak, költségeinek összehasonlítása, valamint a piackutatás ajánlatos. • A vonatkozó előírások, rendeletek betartása szükségszerű.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Felhasznált és ajánlott irodalom • • • • • • •

Oláh György, Alain Goeppert, G.K. Surya Prakash: Kőolaj és földgáz után: a metanolgazdaság, Better Kiadó, Budapest, 2007., ISBN 978-963-86233-5-5. Szerkesztő Bai Attila: A BIOGÁZ, Száz magyar falu könyvesháza Kht., Budapest, 2007., ISBN 978-963-7024-30-6. Heinz Schulz, Barbara Eder: Biogázgyártás, CSER Kiadó, Budapest, 2005., ISBN 963 7418 47 4 Kissné Quallich Eszter: A biogáz, Mezőgazdasági Könyvkiadó, Budapest, 1983, ISBN 963-231-622-3 Fellner Ferenc (Témavezető Hannus István): A biogáztermelés technológiája Magyarországon, Diplomamunka, Önköltséges posztgraduális környezetvédő szakosító képzés, KÖTKORC, Szeged, 1999. Hanczár Tímea (Témavezető Kovács L. Kornél): A metanotróf baktériumok biotechnológiai alkalmazási lehetőségei, Szakdolgozat, SZTE, 2000. A Biogáz tájékoztató füzet, Magyar Biogáz Egyesület, 2008.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

NEHÉZFÉMEK EREDETÉNEK ÉS FELDÚSULÁSÁNAK VIZSGÁLATA EGY KÜLVÁROSI KERTES ÖVEZET TALAJÁBAN Szolnoki Zsuzsanna, Farsang Andrea, Puskás Irén Szegedi Tudományegyetem, Természeti Földrajzi és Geoinformatikai Tanszék, 6722 Szeged, Egyetem u. 2-6., E-mail: [email protected] ABSTRACT Concentrations of heavy metals, which have well-known toxic character, are often higher in urban soils than those in agricultural soils, reflecting several metal inputs arising from human activities. Among urban soils, garden soils have a specific function and significance. Gardens are traditionally devoted to cultivation of vegetables and fruits. Therefore, the urban hobby gardens and the urban vegetable gardens can be potential risky for people since unknown amount of heavy metals can be accumulated into organism of local residents due to consumption of home-produced vegetables and fruits. Our aim is to evaluate degree of heavy metal contamination in the garden soils and to determine metals enriching in the topsoils and their potential sources. Thus, the garden soils in detached houses (43 pieces) on the outskirts were studied. The studied gardens can be categorized into vegetable, fruit, flower ones. The total metal content (As, Co, Cr, Cu, Ni, Pb, Zn) was measured using an ICP-OES technique following a full digestion with aqua regia. Our results demonstrate that the increased metal concentration are typical of the urban garden soils but metal concentrations exceeding the limit value can be observed only in the case of As, Cd, Cu. In accordance with the enrichment factors, it can be established that Cu, Zn, Pb have accumulated in more significant amount in the garden soils, whereas As, Co, Ni and Cr can be considered to be geogenic since they have not accumulated in the garden topsoils. BEVEZETÉS Az 1960-as évek óta végzett kutatások eredményei nyilvánvalóvá tették, hogy a talajok nehézfém koncentrációja rendellenes mértékben megemelkedhet, különösen az ipari körzetekben és a városokban (Csathó, 1994). A fémkoncentrációk a városi talajokban gyakran érzékelhetően magasabbak, mint a mezőgazdasági talajokban, visszatükrözve ezzel számos emberi tevékenységből eredő fémterhelést. Többek között a háztartási és ipari hulladékok elhelyezése, az ipari forrásból származó emisszió, a háztartások fűtése, a gépjármű közlekedés, valamint a múltbéli talajhasznosítás módja eredményezhetik a városi talajok szennyeződését (Thronton, 1991; Norra et al., 2001). Ismeretes, hogy a közlekedés kapcsán nagy mennyiségű ólom került a környezetbe, melynek emissziója az ólommentes üzemanyagok bevezetésével lecsökkent. Ennek ellenére még mindig emittálódik réz, cink, antimon, ólom, kadmium és króm a gépjárművekből, melyek fő forrásai a kipufogó rendszer valamint a gumiabroncsok és fékbetétek kopása (Hjortenkrans et al., 2006). A városi talajok közül a kerti talajokat, művelésükből kifolyólag, a fentieken túl további fémterhelés érheti. A hosszú időn keresztül alkalmazott fémtartalmú növényvédőszerek, a talajba kevert komposztok, szerves- és műtrágyák és egyéb talajjavító anyagok valamint a szennyezett öntözővíz eredményezhetnek fémdúsulást (Csathó, 1994; Alloway, 2004). E talajoknak különleges szerepe és funkciója van: a kertekben hagyományosan zöldségeket és

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

gyümölcsöket termesztenek. Így a városi kertészkedés amellett, hogy esztétikai hobbi is, a friss termények fő forrása (Fetzer et al., 1998). Ezzel együtt viszont már egészségügyi problémák is felmerülnek az esetlegesen szennyezett talajon termesztett zöldségek elfogyasztása révén. Úgy gondoljuk, hogy városi környezet humán-egészségügyi megítéléséhez szükség van a városi kerti talajok szennyezettségére irányuló kutatásokra. Ezért célunk jelen vizsgálattal, hogy felmérjük a szegedi kerti talajok szennyezettségének mértékét, elkülönítsük a geogén és antropogén fémek körét, feldúsulási faktorok segítségével megállapítsuk az antropogén forrásból eredő fémek dúsulásának mértékét, valamint a nehézfémek lehetséges forrásait. MÓDSZEREK Vizsgálati területünk Szeged külvárosában, a körtöltésen kívül elhelyezkedő, közel 1 km2 nagyságú Baktó. A város ÉK-i részén elterülő Baktó telkeit az 1930-as évek elején kezdték el kiosztani, ahol kezdetben főként gyümölcsösöket telepítettek. Ma e városrész kertvárosi lakóövezet, ahol sok családi ház kertjében jelenleg is termelnek zöldséget. A terület eredeti talajtípusa réti csernozjom, amely a kertművelés és lokális antropogén tevékenységek (építkezés, feltöltés) hatására eltérő mértékben módosult, így Baktó talajviszonyára a városi talajok sajátossága, a térbeli változatosság, mozaikosság jellemző (Szolnoki et al., 2011). A Hódmezővásárhely felé vezető nagy forgalmú 47-es főút (ÁNF: 18679 Ej/nap) közvetlenül Baktó mellett halad el, így az út menti kerteket jelentős fémterhelés éri (Farsang et al., 2009). A mintavétel során 43 családi ház kertjéből összesen 88 talajmintát gyűjtöttünk a lakókkal történő előzetes egyeztetés után. A vizsgált kertek jellegüket tekintve a következők voltak: zöldséges kert (25 db), gyümölcsös kert (9 db) és díszítő kert (10 db). Minden kertből 1-1 átlag és 1-1 kontroll mintát vettünk egységes módon a következőképpen: A fedetlen talajfelszínről 6-8 m2-es területről 10-12 részmintát gyűjtöttünk véletlenszerűen a talaj felső 110 cm-es mélységéből, amit aztán jól összekeverve létrehoztuk az átlagmintát. A kontroll minták pontminták, amiket a területegység közepéről vettünk talajfúró segítségével, 80-100 cm mélységből. A laboratóriumi előkészítését követően a mintákból az ”összes” fémtartalmat határoztuk meg királyvizes feltárással, Anton Paar Multiwave 3000 típusú mikrohullámú feltáróval, majd a nehézfémek (Co, Cd, Cr, Ni, Pb, Cu, Zn) és As, valamint referencia elemként Ti mérése Perkin Elmer Optima 7000 DV ICP optikai emissziós spektrométerrel történt. EREDMÉNYEK A Szeged baktói kertek fémterheltségének megítéléséhez a 6/2009 (IV. 14.) KvVM-EüMFVM együttes rendeletben megadott ”B” szennyezettségi határértékeket, valamint a már hatályon kívüli 10/2000 (VI. 2.) KöM-EüM-FVM-KHVM együttes rendeletben megadott ”A” háttér koncentrációkat vettük alapul. Az ”A” háttérérték egy anyag természetes vagy ahhoz közeli állapotot jelző koncentrációja a talajban, míg a ”B” szennyezettségi határérték az a szennyezőanyag koncentráció, amelyet meghaladva a talaj szennyezettnek tekinthető. Az ”A” érték a szennyezetlen talaj felső határát jelenti, amikor még minden talajfunkció ép, ezt meghaladó koncentráció esetén sérül a talaj multifunkcionalitása. Az ”A” értéknél a tényleges háttérérték lokálisan alacsonyabb, vagy geológiai okok miatt magasabb is lehet. A ”B” értéket meghaladó koncentráció esetén a multifunkcionalitás megszűnik, a talajhasználat korlátozott, a veszélyt reálisnak tekintjük (Kádár, 2007). 1. táblázat: Szeged Baktó kerti talajainak nehézfémtartalma (ppm)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

a 0-10 cm-es mélységben (n=44) Minimum Maximum Átlag Szórás "A" érték "B" érték "A"-t meghaladó minták száma "B"-t meghaladó minták száma

As 3,06 15,89 7,40 2,40 10 15

Zn 32,82 198,71 81,10 32,14 100 200

Cd 0,27 2,86 0,56 0,39 0,5 1

Pb 5,11 60,85 16,24 8,68 25 100

Ni 10,04 35,60 22,69 4,86 25 40

Co 2,38 9,26 5,56 1,50 15 30

Cr 14,08 53,97 32,46 7,01 30 75

Cu 18,51 579,84 60,16 84,90 30 75

4

9

15

2

11

0

30

27

1

0

2

0

0

0

0

7

A kerti talajok felszíni szintjében (0-10 cm) mért fémkoncentrációkat az 1. táblázat szemlélteti. A kobalt kivételével minden vizsgált fém meghaladja az ”A” háttér koncentráció értékét a minták valahány százalékában, a legnagyobb ez az arány a réz esetében (77,3%), ezt követi a króm (70,5%), a kadmium (38,6%) és a nikkel (25%). A cink, arzén és ólom esetében ez az arány 25% alatt marad. A ”B” szennyezettségi határértéknél magasabb koncentrációkat három fém, az arzén, kadmium és réz esetében mértünk. Az arzén csak egy, a kadmium kettő, míg a réz hét kertben is meghaladta a ”B” szennyezettségi határértéket. 100 90 80 70 60

Zöldséges kert Gyümölcsös kert

ppm 50

Díszítő kert

40 30 20 10 0 As

Zn

Cd

Pb

Ni

Co

Cr

Cu

2. ábra: A különböző kerttípusokban mért fémkoncentrációk átlagainak összehasonlítása A különböző kerttípusokban mért fémkoncentrációkat összehasonlítva jól látszik, hogy a Zn, Pb, és Cu átlagai a gyümölcsösökben a legmagasabbak, ezt követi a zöldségeskert, majd a díszítő kert (2. ábra). A kobalt, ami egyetlen mintában sem haladta meg az ”A” háttérértéket, minden kerttípusban közel azonos koncentrációval bír, így feltehetően e fém esetében nincs antropogén hozzájárulás. A fémkoncentrációk a réz esetében különülnek el leginkább aszerint, hogy milyen a kert hasznosítási típusa (3. ábra). Ez egyértelműen azt erősíti, hogy a kerti talajok réztartalmának kialakulásában az antropogén hozzájárulás is jelentős tényező. Mivel a tényleges háttér koncentráció az ”A” értéknél lokálisan alacsonyabb vagy esetleg magasabb is lehet, azt vizsgálni, hogy a fémek valóban dúsulnak-e a kerti talajok felszíni szintjében, feldúsulási faktorok segítségével tudjuk. A feldúsulási faktorokat a következő képlettel számoltuk: [E ]SH /[ER ]SH , EF = [E ]RH /[ER ]RH ahol E a kérdéses elem, ER a referencia elem koncentrációja (mg/kg) a talajfelszíni (SH) szintjében (0-10 cm) és a referencia (RH) szintben (80-100 cm), ugyan azon a mintavételi helyen (Bourennane et al., 2010). Ez a feldúsulási faktor a tényleges elemkoncentrációk

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helyett a kérdéses elem és egy referencia elem arányát hasonlítja össze az alapkőzetben és a feltalajban. Ha a feldúsulási faktor értéke egy vagy a körüli, akkor a felszíni szintben a kérdéses fém nem dúsul, ha a faktor értéke egynél nagyobb, akkor a fém, feltehetően antropogén hozzájárulás következtében dúsul a felszíni szintben. A leggyakrabban használt referencia elemek az Al, Li, Sc, Ti, és Zr (Bourennane et al., 2010), melyek közül jelen munkában a titánt választottuk referencia elemnek. A titán gyakori kőzetalkotó elem, ásványai a talajban nehezen mállanak, így a talaj konzervatív elemének számít (Kabata-Pendias, Pendias, 2001). 160

ppm

120 80

┬ max. ┴ min. + átlag ─ medián ┌┐ 75% └┘ 25% ▼ kiugró érték

40 0 Díszítõ kert

Gyümölcsös kert Zöldséges kert

3. ábra: A réz koncentrációinak eloszlása a különböző kerttípusokban A titán referencia elemmel számolt feldúsulási faktorokat a 2. táblázatban közöljük. A feldúsulási faktorok alapján megállapítható, hogy a vizsgált fémek közül a réz az, ami legnagyobb mértékben feldúsul a városi kerti talajokban. A városi kertek réztartalma átlagosan több mint három és félszerese a geogén fémtartalomnak, de akad olyan zöldséges kert is, ahol a réz a harmincszoros feldúsulást is megközelíti. A réz után a legnagyobb mértékben a cink és az ólom halmozódik fel a kerti talajok felszíni szintjében, mind két fém átlagosan közel két és félszeresére dúsul. A kertekben a kadmium, ami erősen toxikus, átlagosan másfélszerese a geogén háttérnek. A króm annak ellenére, hogy a kertek nagy százalékában (70,5%) lépte túl az ”A” háttér koncentrációt, feldúsulási faktora alapján csak kis mértékben dúsul (2. táblázat), míg az arzén, nikkel és kobalt, eltekintve egyes esetektől, nem dúsulnak a kerti talajokban, geogén eredetűnek tekinthetők. 2. táblázat: A Ti referencia elemmel számolt feldúsulási faktorok (n=44) EF Minimum Maximum Átlag Szórás

As 0,4 1,9 0,9 0,4

Zn 1,1 6,6 2,7 1,1

Cd 0,6 4,8 1,5 0,7

Pb 0,6 5,4 2,5 1,0

Ni 0,5 1,7 1,0 0,2

Co 0,5 1,4 0,9 0,2

Cr 0,6 2,0 1,1 0,3

Cu 0,8 29,9 3,6 4,4

KÖVETKEZTETÉSEK A réz, ami a kertek legnagyobb százalékában (77,3%) meghaladta az ”A” háttérértéket és hét kertben még a szennyezettségi határértéket is, feldúsulási faktora alapján megállapítható, hogy jelentős mértékben (átlagosan három és félszeresére) dúsul a kertekben. A réz többlet forrása kettős lehet, hiszen a majdnem minden kertet érintő feldúsulás a közlekedésre, mint lehetséges szennyező forrásra enged következtetni, ugyanakkor a gyümölcsös kertekben

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tapasztalt magasabb réz koncentrációkat a réz tartalmú növényvédőszerek eredményezhetik. A cink feldúsulási faktora alapján minden kertben feldúsul, átlagosan 2,7-szeresére, amit okozhat egyrészt a közlekedés, de a talajba kevert szerves trágya is eredményezheti a cink dúsulását (Wuzhong et al., 2004). Az ólom, annak ellenére, hogy az ”A” háttérértéket csak néhány kert esetében haladta meg, feldúsulási faktora alapján mégis antropogén eredetűnek tekinthető. Az ólom még az ólmozott üzemanyagok használata során kerülhetett a talajba, ezt erősíti az a megállapítás, hogy a legmagasabb ólomkoncentrációkat az út menti kertekben mértük. A kadmium átlagosan másfélszeresére dúsul a kerti talajokban, melynek forrásai a közlekedés mellett a szerves és műtrágyák lehetnek. A króm a kertek nagy számában haladta meg az A háttérértéket, feldúsulási faktora alapján azonban csak kis mértékben dúsul, míg az arzén és nikkel, eltekintve egyes esetektől, nem dúsul a kerti talajokban. A kobalttartalom a kertekben egyértelműen csak a geológiai háttérből származik. FELHASZNÁLT IRODALOM Alloway B. J. (2004): Contamination of soils in domestic gardens and allotments: a brief overview. Land Contamination & Reclamation, 12 (3), 179-187. Bourennane H., Douay F., Sterckeman T., Villanneau E., Ciesielski H., King D., Baize D. (2010): Mapping of anthropogenic trace elements inputs in agricultural topsoil from Northern France using enrichment factors. Geoderma, 157, 165-174. Csathó P. (1994): A környezet nehézfém szennyezettsége és az agrártermelés. MTA-TAKI Budabest, p. 175. Farsang A., Puskás I., Szolnoki Zs. (2009): Human health risk assessment: a case study of heavy metal contamination of garden soils in Szeged. AGD Landscape and Environment, 3 (1), 11-27. Fetzer K., Enricht E., Grenzius R., Kubiniok J., Schwartz C., Morel J.L. (1998): Garden soils in South-Western Germany (Saarland) and North-Eastern France (Lorraine). 16th World Congress of Soil Science, Montpellier (France), 20–26 August 1998, CDROM, symposium 28, 7 pp Hjortenkrans D., Bergbäck B., Häggerud A. (2006): New metal emission patterns in road traffic environment. Environmental Monitoring and Assesment 117. pp.85-98 Kabata-Pendias A., Pendias H. (2001): Trace elements in soils and plants. (3th edition) CRC press Kádár I. (2007): A talajszennyezés megítélése kutatói szemmel. Agrokémia és Talajtan, 56 (2) 391-408. Norra S., Weber A., Kramar U., Stüben D. (2001): Mapping of trace metals in urban soils. Journal of Soils and Sediments, 1 (2), 77-97. Szolnoki Zs., Farsang A., Puskás I. (2011): Szeged külvárosi, kerti talajainak osztályozása. Talajvédelem Különszám pp. 93-102. Thronton I. (1991): Metal contamination of soils in urban areas. In: Soils in the Urban Environment. (Eds.: Bullock P. Gregory P.J.) Blackwell, Oxford, pp. 47-75 Wuzhong, N., Haiyan, M., Jixiu, H., Xinxian, L. (2004): Heavy metal concentrations in vegetable garden siols from the suburb of Hangzhou, People’s Republic of China. Bull. Environ. Contam. Toxicol. 72. 165-169.

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ROLE OF BACTERIAL AUXIN-LIKE COMPOUNDS AND SIDEROPHORES IN THE ROOT DEVELOPMENT AND HEAVY METAL UPTAKE OF SALIX VIMINALIS L. IN THE PRESENCE OF LEAD AND CHROMIUM Ágnes Dergez, Ádám Fejes, Péter Kesserű Bay Zoltán Foundation for Applied Research Institute for Biotechnology, Szeged, Hungary e-mail: [email protected] ABSTRACT A large Hungarian consortium was formed to investigate the effectiveness of phytoremediation on heavy metal polluted sites. In previous study 29 endemic bacterium strains from the same soil samples isolated and identified. A consortium of the collected bacteria could improve the root development of Salix viminalis L. in the presence of 100 µM Cr3+ and Pb2+, which heavy metals inhibited the root development without the bacteria. Moreover, the bacterial consortium also changed the distribution of heavy metals in the plant tissues. In the presented work, we tried to find the potential reasons for the changed root development and distribution of heavy metals. The production of bacterial auxin-like molecules and siderophore compounds was hypothesized and investigated. According to our results, all strains of the bacterial consortium were able to produce auxin-like and siderophore compounds. In most cases, siderophore production of bacterium strains was as effective as EDTA (ethylene diamine tetraacetate, as synthetic chelator). Acinetobacter strains were found to be the best siderophore and auxin-like compound producers from the applied bacteria. INTRODUCTION Organisms, living in the rhizosphere, can facilitate the metal uptake of plants by means of different reasons. On the one hand, bacteria and other microorganisms can produce such compounds (for example plant hormones), which have influence on the plant growth. These bacteria are so-called PGPR (plant growth promoting rhizobacteria) (McMillan, 2007). On the other hand, rhizosphere microorganisms have influence on the availability of metals by the means of production such compounds, which facilitate the metal solubility in the soil solution for example by decreasing of pH or forming complexes (Tassi, és mts., 2008). These complex forming, chelating compounds, which are increase the availability for plants and solubility of metals in the soil, are called siderophores. Since siderophores facilitate the nutrient supplies of plants, they have an important role also in the plants growth. Furthermore, they can change the oxidation state of the metals facilitating the phytoremediation processes (Salt és mts., 1999). According to Neilands (1993), siderophores are small compounds (smaller then 1500 Da), which forming complex with Fe3+ through oxygen atom; in this way they can extract the Fe3+ from the environ and can get it into the microbial cells. Although siderophores are specific for Fe3+, they can form complexes with other three valent metals (e.g. pl. Ga3+, Cr3+ , Al3+, Sc3+, In3+), with essential metal ions (e.g. Mg2+, Mn2+, Ca2+) Furthermore they can form complexes with radionuclides (e.g. Pu4+and the other actinides) (Bulman 1978).

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The root system of plants and their rhizosphere microorganisms can influence together the plant development. During the interference between the plants and microorganisms, the plant growth regulators (PGR) producted by microorganisms have the most important role. The PGR compounds are such natural organic compounds, which can influence the physiological processes of plants in lower concentration then the nutrients and vitamins (Arshad és mts., 1998). The plant growth regulator effects are caused also by PGPR, which can modify the microenvironment of the root by antibiosis or antagonism, and by the PGR compounds, which are principally plant hormones, such auxins, gibberellins, cytokinins (McMillan, 2007). MATERIALS and METHODS The applied rhizosphere bacteria From the rhizosphere of Salix sp. grown on HM contaminated site (Mártély, Hungary) twenty nine bacterium strains were isolated during previous study of Bay Zoltán Foundation for Applied Research Institute for Biotechnology (BAYBIO). In the presence of the consortium of these bacteria, willow cutting were able to develop roots even in the presence of toxic concentration of lead and chromium. The member of the consortium belonged to the Pseudomonaceae, Bacillaceae and Enterobacteriaceae families. Enrichment of the bacterial consortium The bacterial strains were maintained on Bouillon agar and they were enriched in Bouillon medium at 37°C for 48h. These single bacterial cultures were utilized for investigation of siderophore and auxin production, antagonism. These single cultures were mixed to make a consortium and they were breeding together at 37°C for 48h to make a bacterial consortium. This consortium was utilized for the investigating and heavy metal tolerance, of root development of willow cuttings in the presence or absence of rhizosphere bacterial consortium and/or Cr3+, Pb2+ and Zn2+ for the determination of siderophore and auxin production. During the root development experiment, Hoogland medium was applied in 10fold dilution in the presence or absence of 100 μM. CrCl3, Pb(NO3)2 or ZnSO4. Determination of heavy metal tolerance The heavy metal tolerance of the bacterial consortium was determined by turbidimetric methods with Hach Lange DR 5000 spectrophotometer at 600nm. Investigation of siderophore production The produced siderophores of the applied bacterium strains were detected by O-CAS (overlaid Chrome azurol S) method by Pérez-Miranda et al. (2007) modifying the HDTMA content of the CAS agar to 10%. The amount of produced siderophores of the applied bacterium strains and their consortium during the root development experiment was measured by ferric perchlorate photometric method (Calvente et al., 2001). The absorbance was measured at 305 nm with Hach Lange DR 5000 spectrophotometer. The siderophore production was correlated to the chelating capacity of EDTA. Investigation of auxin production The auxin produced by the applied bacterium strains and their consortium during the root development experiment was measured by (Glickmann et al., 1994). The auxin content was referred to indole acetic acid (IAA).

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RESULTS Based on previous study, the consortium of the applied rhizosphere bacterium strains had effect on the root development and heavy metal uptake, which was thought to be caused by bacterial siderophore and auxin production. First the antagonistic effect between the rhizosphere bacterium strains, and their heavy metal tolerance were investigated. Based on these investigations, antagonistic effect is not typical between the applied rhizosphere bacteria, it was detected only in some cases in fairly low degree. Both Cr3+, Pb2+ and Zn2+ increased the proliferation of the rhizosphere bacterial consortium in the presence of 0,1 mM heavy metal, which Cr3+ and Pb2+ concentration was totally toxic for the willow cuttings during the root development experiment. Although, 0,5 mM Pb2+ and Zn2+ decreased the viability, till Cr3+ had inhibitory effect only in 3 or more mM concentration for the bacterial consortium. The applied heavy metal concentration could not inhibited totally the bacterial proliferation, consequently some strains could tolerate even the higher heavy metal concentrations as well. The results of siderophore investigations showed that all bacterial strains of the rhizosphere bacterial consortium could produce siderophores. Moreover, based on the quantitative measurements, the siderophores produced by the bacteria could chelating such amount of Fe3+ as 1,5-7 mM EDTA. This amounts was similar to the siderophore production of microorganisms (Aspergillus niger, Bacillus cereus, Staphylococcus aureus) documented by Pérez-Miranda et al. (2007). Aspergillus strains (1525, 1527, 1528, 1539 and 1540), Bacillus cereus (1533), Bacillus mycoides (1517, 1531), Bacillus sp. (1538) and Citrobacter sp. (1521) produced by far the highest siderophore level. Furthermore, during the root development experiment, the siderophore content was higher in the bacterial treated samples, than the untreated samples (Table 1.). The environmental bacteria of the non-sterile condition presumably caused the low concentrations of siderophore in the untreated samples,. Table 1. Produced total indolic compounds and siderophore concentrations during the root development experiment Siderophore content Indolic compond SD Sample (mM) regarding to EDTA (μgml-1) Control n.d. 0,01 Treated with rhizosphere bacteria 0,112 ±0,095 0,02 2+ Treated with Zn n.d. 0,06 2+ Treated with Zn and 0,133 ±0,081 0,10 rhizosphere bacteria Treated with Pb2+ n.d. 0,01 Treated with Pb2+ and 0,148 ±0,004 0,08 rhizosphere bacteria Treated with Cr3+ n.d. 0,01 3+ Treated with Cr and 0,078 ±0,024 0,05 rhizosphere bacteria n.d.: not detected During the root development experiment, willow cutting could not develop (or only a little) root in the presence of 100 μM Pb2+ and Cr3+. However, in the presence of the rhizosphere bacterial consortium the willow cuttings could develop strong (even stronger than in case of the absolutely untreated control) root system in the presence of Pb2+ and Cr3+ at the given concentrations. Since this kind of root development alluded to the presence of auxin (or other

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SD <±1% ±17% <±1% ±10% <±1% <±1% <±1% ±20%

The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

plant hormones), the bacterial auxin production was also investigated by colorimetric methods. According to the results, all bacterial strains of the rhizosphere bacterial consortium could produce auxin or a sort of indolic compounds. Regarding to the auxin production, also the Acinetobacter sp. strains seemed to the best. During the root development experiment, the total amount of indolic compounds was also measured and indolic compounds only in the bacterial treated samples could be detected in approximately 0,1 μgml-1 concentration (Table 1.). This concentration is not high, however according to Kerk et al. (2000), maybe enough to have some effect on root development. Although, lead and chromium inhibited the root development of the plants, the consortium of rhizosphere bacteria of willow was able to supply auxin-like compounds and plants could develop roots. CONCLUSIONS • Consequently, antagonistic effect is not typical between the applied rhizosphere bacteria. • The applied heavy metals in 0,1 mM concentration, which concentration was toxic for the willow cuttings, had a little positive effect on the bacterial proliferation. • The consortium of the applied rhizosphere bacterium strains had effect on the root development and heavy metal uptake, which could be caused by bacterial siderophore and auxin production. According to our results all applied bacterium strains could produce siderophore and auxin like compounds in such concentration, which could have influenced the heavy metal uptake and the root development in the presence of 100 μM Cr3+, Pb2+ and Zn2+. LIST OF REFERENCES Arshad, M. - Frankenberger, W.T.: Plant grow regulating substances in the rhizosphere: Microbial production and function; Advences in agronomy, 62 (1998) 46-151. Bulman, R. A.: Chemistry of plutonium and the transuranics in the biosphere; Struct. and Bond., 34 (1978) 39-77. Calvente, V., Orellano M.E., Sansone, G., Benuzzi, D., Sanz de Tosetti, M.I.: Effect of nitrogen source and pH on siderophore production by Rhodotorula strains and their application to biocontrol of phytopathogenic moulds; Jourmal of Industrial Microbiology & Biotechnology, 26 (2001) 226-229. Glickmann, E. - Dessaux, Y.: A critical examination of the specificity of the Salkowski reagent for indolic compounds produced by phytopathogenic bacteria; Apllied and Enviromental microbiology, 62 (1994) 793-796. Kerk N.M., Jiang K., Feldman L.J., 2000. Auxin Metabolism in the Root Apical Meristem. Plant Physiology, 122, 925-932 McMillan, S.: Promoting growth with PGPR; The Canadian Organic Grower, (2007) 32-34 Neilands, J. B: Siderophores; Archives of Biochemistry and Biophysics, 302 (1993) 1-3. Pérez-Miranda, S. - Fernández, F.J.: O-CAS, a fast and universal method for siderophore detection; Journal of Microbiological Methods, 70 (2007) 127-131. Salt, D.E. - Raskin, I. - Kumar, N.P.A.: Conversion of metal oxidation states by phytoreduction; United States Patent, US005928406A (1999) Tassi, E. Pouget, J. Petruzzelli, G. Barbafieri, M.: The effects of exogenous plant growth regulators in the phytoextraction of heavy metals; Chemosphere, 71 (2008) 66-73.

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A TALAJVÍZ TOXIKUS ELEMTARTALMÁNAK TÉR- ÉS IDŐBELI VÁLTOZÁSA VÁROSI KÖRNYEZETBEN, SZEGEDEN Fejes Ildikó, Farsang Andrea Szegedi Tudományegyetem, Természeti Földrajzi és Geoinformatikai Tanszék, 6722 Szeged, Egyetem u. 2-6. e-mail: [email protected] ABSTRACT This paper presents the spatial-temporal changes of the toxic element content in groundwater within urban area, Szeged (Hungary). In the course of our work groundwater contamination was monitored using twenty-eight sampling wells from the groundwater monitoring network of Szeged. The water samples were collected every month from October of 2010 and the nickel, lead, arsenic, cobalt, chrome, zinc, copper and cadmium concentrations were measured. We examined the relationship of this different pollutants and their distribution in the city. According to the results, the groundwater of Szeged is contaminated with lead, nickel, copper, zinc and arsenic, mainly in the downtown, close to the river Tisza. Statistical relationship, used Spearman’s rank correlation, was determined among the siderophile (namely chrome and nickel), and chalcophile elements (lead, zinc, cadmium, copper). The temporal changes are similar by the most components, and compared to the average monthly rainfall the concentrations follow the rainfall changes with one month delay. The poorest groundwater quality in the examined period was measured at the beginning of winter and early spring, the autumn months characterized the clearest water. BEVEZETÉS Nagyvárosi környezetben, a fokozott antropogén hatások következtében növekvő probléma a felszín alatti vizek elszennyeződése. Az emberi tevékenység erősen fenyegeti a felszín alatti víz minőségét és készleteit, valamint a lakosság létfenntartása is függ ezek minőségétől (Marton, 2009), ezért a vízkészletek megóvása kiemelt fontosságú. Ezen kívül a városok alatti kontaminálódott talajvíz nemcsak környezeti, hanem humán-egészségügyi szempontból is veszélyes lehet. Mivel a talajvíz összetétele állandóan változik, komplex vizsgálatához folyamatos monitoring tevékenységre van szükség. Munkánk során a szegedi talajvíz minőségének vizsgálatához a város kiterjedt talajvízmegfigyelő monitoring kúthálózatát vettük igénybe. Ezt a monitoringrendszert használva Szeged talajvizének kutatási programja 1972-ben indult és 1987-ben készült el egy átfogó tanulmány, mely részletesen elemezte a talajvízjárást, valamint a talajvíz kémiai összetételét az 1980 és 1984 közötti időszakra vonatkozóan (SO42-, Na+, Ca2+, Mg2+, Cl-, HCO3-) (Kaszab, 1987). E tanulmány megjelenését követően is több időpontban történtek felmérések a talajvíz minőségi állapotával kapcsolatban (Kaszab, 2006; Farsang és Fejes, 2009). A korábbi vizsgálatok erős szennyezettségre utalnak, így szükségessé vált egy új, idősoron alapuló állapotfelmérés elvégzése a szegedi talajvízrendszerre vonatkozóan.

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Tanulmányunkban bemutatjuk a szegedi talajvíz minőségvizsgálatának főbb eredményeit, beleértve a térbeli és az időbeli változásokat, az egyes szennyezési gócpontok lehatárolását, a komponensek közötti statisztikai kapcsolatokat és összefüggéseket a csapadékmennyiséggel. ANYAG ÉS MÓDSZER A vizsgálatokat a szegedi talajvíz-megfigyelő monitoring-rendszerből kiválasztott – mintázásra alkalmas – 28 db kút esetében végeztük Szeged területén, melyek kijelölésénél arra törekedtünk, hogy a várost egyenletesen lefedő hálózatot kapjunk. A méréssorozatot 2010 októberében kezdődött egy éves időtartamra tervezve, havi rendszerességű mintavétellel. Jelen tanulmányunk az első tíz hónap (2010 okt. – 2011 júl.) mérési eredményein alapul. A mintákat az MSZ ISO 5667-11:2009 szabványnak megfelelően, tisztító szivattyúzást követően (melynél háromszoros víztérfogatot termeltünk ki) a frissen utánpótlódott vízből vételeztük, kiküszöbölve az esetleg jelen lévő önálló fázisú vagy oldott szennyeződések nem kívánatos mobilizációját. A helyszínen került sor a pH, a hőmérséklet, az elektromos vezetőképesség, az összes sótartalom és a vízállás mérésére. A mintákat légmentesen lezárt flakonokban az SZTE TTIK Talaj- és Vízvizsgálati Laboratóriumába (NAT-1-1437 (2009)) szállítottuk, ahol 8 komponensre – réz (Cu), kadmium (Cd), kobalt (Co), króm (Cr), nikkel (Ni), ólom (Pb), cink (Zn), arzén (As) – vizsgáltuk meg. A komponensek koncentrációinak mérése optikai emissziós spektrofotometriás módszerrel, Perkin Elmer ICP OES Optima 7000 DV típusú műszerrel történt. Választásunk azért esett erre a 8 komponensre, mert a leggyakoribb szennyezőanyagok közé tartoznak városi környezetben, amelyek releváns vízminőség-romlást okoznak (Szalai et al., 2004). A vízminősítést a 6/2009. (IV. 14) KvVMEüM-FVM együttes rendelet (a felszín alatti víz és a földtani közeg védelméhez szükséges határértékekről) (B) szennyezettségi határértékei alapján végeztük el. A koncentrációk eloszlását bemutató térképeket ESRI ArcGIS 10 szoftver segítségével jelenítettük meg. A statisztikai számításokat SPSS 18.0 szoftverrel végeztük el, melynél a korreláció számítások előtt megvizsgáltuk az egyes változók eloszlásának normalitását. A nem normál eloszlású változók értékeit normalizáltuk, ezután korrelációanalízist végeztünk Spearman-féle korrelációs együtthatóval. EREDMÉNYEK ÉS ÉRTÉKELÉSÜK Kutatásunk során a kontamináció szempontjából történő elemzést a 6/2009. (IV. 14) KvVMEüM-FVM együttes rendelet (B) szennyezettségi határértékeire alapoztuk (a havi átlagértékeket használva), mely feletti értékeknél a mintákat már szennyezettnek tekintettük. A kutak egészét vizsgálva Szeged talajvize számos toxikus mikroelemmel terhelt, néhány esetben extrém nagy szennyezettségű gócponttal. A vizsgált elemek közül a Cd, a Co és a Cr határértékei nem érték el a szennyezettségi határértéket egy vízmintában sem, sőt a Co és a Cd mennyisége általában csak a háttérkoncentráció közelében mozgott. A Cr-nál a legmagasabb értékek 4 µg/l körül adódtak (a belvárosi kutaknál), ám ezen értékek is messze elmaradnak az 50 µg/l-es határértéktől. A Ni esetében két minta volt szennyezett (22. és a 28.), melyek a belváros szívében helyezkednek el. Szintén e két kút vizében mértük a legmagasabb Pb koncentrációkat, melyek több mint háromszorosan átlépték a megengedett értéket (10 µg/l), valamint további három minta (15., 17., 24.) kontaminálódott Pb-mal, amely azért is kiemelendő, mert az Pb (és a Ni) erősen toxikus elem, és a rákkeltő anyagok közé tartozik. As-nal 4 kút vize szennyezett (10., 22., 23., 24), melyek közül három a Tisza

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közvetlen közelében helyezkedik el, és 20 µg/l feletti értékeket mutatnak a 10 µg/l-es B határértékhez képest. Mivel az As a minden esetben veszélyes anyagokat jelölő K1 kategóriába sorolható, kiemelt figyelmet kell fordítanunk a szennyezett területekre és megvizsgálni az esetleges hatásait a Tiszára vonatkozóan. A Cu és a Zn 200 µg/l-es határértékét számos minta meghaladta, melyek ilyen magas koncentrációban már toxikus hatásúak. Cu-zel hét minta szennyezett, a 22. és a 28. kútnál ötszörös határérték túllépést állapítottunk meg. Zn esetében a minták 64%-a kontaminálódott, néhány kút esetében kiugróan magas értékeket, 8000 µg/l (22.) és 4800 µg/l (24.) körüli koncentrációkat is észleltünk. Ismert tény, hogy a vízben jelenlévő, különböző fémek toxikus hatása szinergikus (egymást felerősítő) lehet, mely igaz a Zn és a Cu együttes jelenlétére is (Barótfi, 2000), tehát a mindkét fémmel erősen szennyezett kutak különösen nagy toxikus hatással bírhatnak.

1. ábra: A szennyezések térbeli elhelyezkedése a (B) szennyezettségi határérték feletti komponensek száma alapján A szennyezések térbeli eloszlását tekintve (1. ábra) egyértelműen három belvárosban elhelyezkedő kút jellemezhető a legnagyobb szennyezettséggel (22., 24., 28). A 22. kútból származó vízminta – mely a Klinikák udvarában, közvetlenül a Tisza partján található – öt komponensnél haladta meg a vonatkozó határértéket, néhány esetben extrém nagy koncentrációkkal. A 24. és a 28. mintavételi pont szintén a Tiszához közel helyezkedik el; előbbi a város legnagyobb közparkjában, a Széchenyi téren, míg utóbbi az újszegedi oldalon, a töltés lábánál. Kevésbé kontaminálódott a talajvíz külterületen, kertes házas, illetve falusias jellegű városrészeken: a gyálaréti Holt-Tisza partján lévő 19., az Öthalom környékén elhelyezkedő 2. és 3., a baktói 8. és a város közigazgatási határán kívül eső 9. kút a vizsgált szennyezőanyagoktól teljesen mentes. Kutatásunkban statisztikai vizsgálatokkal tártuk fel az egyes szennyesések hátterében álló geokémiai folyamatokat, illetve csoportokat különítettünk el az egyes komponensekre vonatkozóan. Szignifikáns pozitív korrelációs kapcsolat állapítható meg a sziderofil elemek között (Ni és Cr), melyek a vassal fordulnak elő a természetben. Bár a Co is a vascsoportba tartozik, valószínűleg alacsony értékei miatt nem mutatható ki összefüggés. Erősen korrelálnak egymással a kalkofil elemek, a Cu, a Zn, a Cd és az Pb, melyek közös jellemzője

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a kénnel való nagy affinitás. Az As-t tekintve nem állapítható meg erős korrelációs kapcsolat egyik elemmel sem. A Spearman-féle korreláció analízis eredményeit az 1. táblázat tartalmazza. 1. táblázat: Spearman-féle korrelációs együtthatók a vizsgált elemekre vonatkozóan Cu Pb Zn Cd Co Cr Ni As

Cu 1 0,68** 0,87** 0,55** 0,38** 0,15** 0,20** 0,09

Pb

Zn

Cd

Co

Cr

Ni

As

1 0,59** 0,34** 0,27** 0,12** 0,17** 0,18**

1 0,50** 0,31** 0,14* 0,19** 0,03

1 0,23** 0,19** 0,24** 0,08

1 0,05 0,12 0,06

1 0,91** 0,02

1 0,04

1

* p < 0,05 ** p < 0,01 A szennyezések időbeli változását tekintve a legmagasabb koncentrációk decemberben, illetve márciusban adódtak, minden mért elem esetében. A havi átlagos koncentrációk vonaldiagramjait összevetve nagyfokú hasonlóságot fedezhetünk fel (2. ábra), ugyanis az őszi időszakot, valamint a januári, az áprilisi és a májusi hónapokat alacsonyabb koncentrációk jellemezték, míg a decemberit, a februárit, a márciusit és a júliusit magasabbak.

2. ábra: A havi átlagos fémkoncentrációk és a havi csapadék összeg (Forrás: ATIKÖVIZIG) összehasonlítása diagramokon A komponensek időbeli változását a csapadékmennyiség változásával összehasonlítva kiderül, hogy a koncentrációk és a csapadékmennyiség egymással fordítottan arányos, tehát a csapadékosabb hónapokat egy alacsonyabb szennyezőanyag-koncentrációjú hónap követte. Ezt a megállapítást statisztikai számítások is alátámasztják: a Sperman-féle korrelációs együttható pl. Zn-re vonatkozóan - 0,630* ; Cu-re - 0,536*; Pb-ra - 0,654** (ahol * p < 0,05; ** p < 0,01). Természetesen a szennyezőanyag-tartalmat a csapadékmennyiségen kívül

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számos egyéb tényező is befolyásolhatja, mint például a talajvíztükör mélysége vagy a talaj vízáteresztő képessége (Szabó et al., 2010). KONKLÚZIÓ • Szeged talajvize számos toxikus elemmel terhelt, néhány pontban extrém nagy szennyezés mutatható ki. • A vizsgált vízminőségi paraméterek közül a réz, a cink, a nikkel, az ólom és az arzén esetében a minták jelentős részében a megengedett (B) határérték feletti koncentrációkat kaptunk. • A térbeli eloszlást tekintve a legszennyezettebb kutak a belvárosban, illetve a Tisza közelében helyezkednek el, míg a város peremterületein kevésbé kontaminálódott a talajvíz. • Az idősorok alapján a talajvíz minősége a megfigyelt időszakban tél elején, valamint kora tavasszal volt a legrosszabb, és ősszel a legkedvezőbb. • Statisztikai vizsgálatok szerint szignifikáns, pozitív korreláció mutatható ki a kalkofil elemek, valamint a vascsoport két eleme között. A kobalt és az arzén esetében nem találtunk statisztikai kapcsolatot. • A vizsgált elemek időbeli változását ábrázoló vonaldiagramok nagy hasonlóságot mutatnak, melyek egy hónapos késéssel követik a havi csapadék összeg változásait; az egyes komponensek átlagos havi koncentrációi erősen korrelálnak a csapadékmennyiséggel. IRODALOMJEGYZÉK Alsó-Tisza Vidéki Környezetvédelmi és Vízügyi Igazgatóság, ATIKÖVIZIG. http://www.atikovizig.hu/vizrajzx/csapadek.aspx Barótfi I. (2000). Környezettechnika. Mezőgazda Kiadó, Budapest, p. 981. Farsang A., Fejes I. (2009). Contamination and human health risk of groundwater in Szeged, Proc. 11th regional conference on environment and health, In: Papp A. (ed.), 11th regional conference on environment and health. Szeged, Hungary, 15/16 May. 2009. Kaszab I. (1987). Építésföldtani összefüggések Szeged és környéke felszínközeli üledékeiben. A MÁFI és a Szeged Városi Tanács közös kiadása, Budapest, 1987, p. 113. Kaszab I. (2006). Szeged talajvizének geokörnyezeti állapota. In: Galbács Z. (szerk.), Proceedings of the 13th symposium on analytical and environmental problems. Szeged, Magyarország, 2006.09.25. MTA Szegedi Akadémiai Bizottság, Szeged, pp. 270-276. MSZ ISO 5667-11: 2009 2. Vízminőség. Mintavétel. 11. rész: A felszín alatti vizek mintavételéhez. Marton L. (2009), Alkalmazott hidrogeológia. ELTE Eötvös Kiadó, Budapest, p. 626. Szabó Gy., Angyal A., Csikos A., Bessenyei É., Tóth E., Kiss P., Csorba P., Szabo Sz. (2010). Examination of the groundwater pollution at lowland settlements. Studia Universitatis "Vasile Goldis", Seria Stiintele Vietii, 20., 4., 2010, pp. 89-95. Szalai Z., Jakab G., Madarász B. (2004). Estimating the vertical distribution of groundwater Cd and Cu contents in alluvial sediments (River Danube). In: Aagard P. (ed.), Proceedings of the International Workshop: Saturated and unsaturated zone: integration of process knowledge into effective models: COST action 629, Fate, Impact and Indicators of Water Pollution in Natural Porous Media. Rome, Italy, 5/7 May. 2004., pp. 303-312. 6/2009. (IV. 14) KvVM-EüM-FVM együttes rendelet a felszín alatti víz és a földtani közeg védelméhez szükséges határértékekről, Magyar Közlöny, 51. évf., pp. 14398-14414.

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APPLICATION OF DIFFERENT PSEUDOMONAS AERUGINOSA STRAINS IN MEOR EXPERIMENTS Hajnalka Füvesi, Ákos Koós, Péter Kesserű PhD Bay Zoltán Foundation for Applied Research Institute for Biotechnology ABSTRACT During the MEOR laboratory measurements we applied two different types of Pseudomonas aeruginosa. The strains were able to synthesize of biosurfactant and biopolymer in varying degrees. The reserves conditions can be modelled properly in the MEOR device (T=37 °C, P=1 bar). The bacterial biopolymer solutions resulted in significantly more oil turnout, than the turnout of the conventional process using water. The MEOR activity of Ps. aeruginosa “785” was 21,20 % while Ps. aeruginosa “1604” 19,39 %. Although the MEOR activities were the same, significant difference between the distributions of oil recovery of the two bacteria strains was observed. INTRODUCTION Increasing the capacity of the oil production is one of the most important problems nowadays. The reduced energy of the reserves necessitates the development of several new technologies that fullfil the demand of the growing oil production ([1], [2]). MEOR (Microbial Enhanced Oil Recovery) means microbial methods, for example treatment with biopolymer or biotenside, for improve oil production ([3], [4]). In recent study we have investigated the possibility of the application of exogenous biopolymer synthesized by two Gram-negative Ps. aeruginosa strains in MEOR technology. MATERIALS and METHODS Production of bacterial biopolymers Ps. aeruginosa “785” and “1604” were proliferated in a shaker at 37°C for 24 hour at 180 rpm in Bouillon medium. The biopolymers were produced in modified Bouillon medium at 37°C, which were inoculated with Ps. aeruginosa “785” and “1604” grown in Bouillon medium for 24 hour. The final structure of biopolymer was formed after 5 days. Rheological measurements Rheological properties of biopolymers were measured by rotational viscometer (Brookfield DV-II+ model) at 37°C. The shear rate (1/s) vs. shear stress (N/m2) curve was defined flow curve. MEOR: laboratory measurements The microbial enhanced oil recovery was examined in a self-made laboratory model system. The instrument is appropriate for the simulation of the pressure, temperature and the flow rate of the reservoir water in the reservoir. After adjusting the residual oil saturation, it is unable to extract more oil from the core. A secondary water injection, after the applying of visco-elastic

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biopolymer solution, results enhanced oil recovery. We calculated the total and the enhanced oil recovery, and we monitored the pressure difference during the measurement. The measurements run at T=37 °C and P=1 bar. RESULTS The two Ps. aeruginosa strains were able to synthesize the mixture of biopolymer and biotenzide in different effectiveness. Figure 1. shows the culture of the two Ps. aeruginosa strains where “1604” proved to be pyocyanin (green pigment) producer strain. Figure 1. The Pseudomonas aeruginosa strain “785” and “1604”

These bacteria have biosurfactant (for example rhamnolipid) producing ability, Figure 2. shows the oil clean up zones of the two strains on crude oil after 168 hours. Results revealed that the strain “785” produce more rhamnolipid than the strain “1604”. Figure 2. Clean up zones of Ps. aeruginosa strains

P. aer. 785 on crude oil

P. aer. 1604 on crude oil

Measurements on programmable Brookfield DV-II+ rotational and Anton Paar oscillatory rheometers proved, that the biopolymer produced by both Ps. aeruginosa strains shows viscoelastic behavior and this character is preserved in the diluted form as well. The rheological properties of the biopolymers synthesized by the bacteria strains referred to that exopolymer secreted by “1604” is more stabile and shows higher durability. On the flow curve of the secreted biopolymer of “1604”, higher shear stress values can be observed than with “785” (Figure 3.).

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Figure 3. Flow curves of biopolymers secreted by different Ps. aeruginosa strains

Table 1. Differences between polymer solutions during oil recovery processes Polymer type

Enhanced oil recovery[%]

“785” “1604”

21,20 19,39

Distribution of oil recovery [%] Polymer injection Displacement water phase [%] injection phase [%] 49,98 50,02 100 0

The distribution of the oil recovery differ in situ sub-processes of laboratory MEOR experiments, depending on which bacterial cultures were used in the tests (Table 1.). The results proved that the majority of the recovered oil was detected in the displacement water injection phase in the case of Ps. aeruginosa “785”, while the “1604” marked polymer showed enhanced oil yield during its injection phase during laboratory MEOR measurements. Laboratory experiments proved that MEOR activity of the strain “1604” was rather biopolymer type, while it was biosurfactant type in case of the strain “785”.

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Figure 5. Enhanced oil recovery (ERin) 0.25

biopolymer injection

0.20

water flooding

ERin

0.15

MEOR with Ps.a."785" MEOR with Ps.a."1604"

0.10

secondary water flooding 0.05

0.00 0

1

2

3

4

5

6

7

8

9

10

11

Pore Volume (PV)

CONCLUSIONS • • •

We have isolated two Ps. aeruginosa strains (“785” and “1604”) from oil reservoirs. The strains were able to producing biopolymers and biotenzide in different effectiveness. The rheological measurements proved that both produced polymers are visco-elastic gels. The results of enhanced oil recovery were very significant in both cases (“785” 21,20% - “1604” 19,39%). Although the MEOR activities were the same significant difference between the distributions of oil recovery of the two bacteria strains was observed.

LIST OF REFERENCES [1] Hall, C., Tharakan, P., Hallock, J, Cleveland, C, Jefferson, M.: Hydrocarbons and the evolution of human culture. Nature, 426(6964): 318-322. (2003) [2] Song, S., Zhang, Z., Li, S.: Progress of Microbial Enhanced Oil Recovery in Laboratory Investigation. Petroleum Science, 1(4): 23-30. (2004) [3] Beckmann, J.W.: The action of bacteria on Mineral oil. Ind. Eng. Chem. News, 10(4): 3. (1926) [4] Youssef, N., Elshahed, M.S., McInerney, M.J.: Microbial processes in oil fields: culprits, problems, and opportunities. Adv Appl Microbiol, 66: 141-251. (2009) ACKNOWLEDGEMENTS This work was supported by MOL (Profile regulation and production enhancement by application of biotechnological methods).

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UV-INDUCED PHOTOOXIDATION OF PHENYL UREA PESTICIDES TOXICOLOGY ASPECTS T. Alapi1, J. Farkas2, E. Szabó2, K. Schrantz1, K. Mogyorósi1, L. Manczinger3, E. Sajben3, A. Palágyi3, Cs. Vágvölgyi3, B. Abramović4, A. Dombi2 1

University of Szeged, Department of Inorganic and Analytical Chem., H-6701 Szeged, P.O.Box 440 Hungary 2 University of Szeged, Institute of Material Sciences and Engineering, H-6725 Szeged, Tisza Lajos Krt. 103, Hungary 3 University of Szeged, Department of Microbiology, H-6726 Szeged, Közép fasor 52, Hungary 4 University of Novi Sad, Faculty of Sciences, 21000 Novi Sad, Trg Dositeja Obradovica 3, Serbia [email protected] ABSTRACT Phenylurea herbicides, like diuron, monuron, linuron, are photosynthesis inhibitors killing the entire plant by this effect. These pesticides and their intermediates formed due to their UV induced transformation could be toxic and carcinogenic to animals and humans. Thus, the investigation of the UV induced transformation of these phenyl urea pesticides from toxicology aspects is suitable. In this work, the ecotoxicology effect of the multicomponent solutions formed during the UV photolysis (254 nm) was investigated by Daphtoxkit FTM Magna and Algaltoxkit FTM. The genotoxicology effect of the multicomponent solutions was investigated using the Ames tests. INTRODUCTION Pesticide pollution of environmental is a pervasive problem with widespread ecological consequences. In response, the European Community has implemented programmes for the development of technologies which are useful for reducing pesticide input into water runoff. Wastewaters from agricultural industries and pesticide manufacturing plants may have pesticide contamination levels as high as 500 mg/l [1]. European regulations (European Union Drinking Water Directive 98/83/EC) on drinking water quality set a maximum concentration of 0.1 μg/L for individual pesticides and some of their degradation products, and 0.5 μg/L for total pesticides present. Nevertheless, the concentrations of some pesticides frequently exceed these levels. Diuron and monuron are widely used chlorine containing phenylurea herbicides, which are employed to control a wide variety of annual and perennial broadleaf and grassy weeds. Nowadays, diuron, which is considered a Priority Hazardous Substance by the European Commission, can be detected not only in the agricultural and natural waters but also in drinking waters [2-4]. The commercially available low-pressure mercury vapour lamp (having main output at 254 nm) is a widely applied light source in water disinfection technologies. At the same time, 254 nm light is effective for the photodecomposition of several aromatic pollutants by direct photolysis. However, the efficiency of the UV photolysis in the elimination of the target substances is strongly limited by their molar absorptivity and the quantum yield of the phototransformation. MATERIALS AND METHODS The low-pressure mercury vapor lamp (GCL307T5VH/CELL, LightTech, Hungary, 227 mm arc length) was applied as light source. This lamp has a high purity silica sleeve (307 mm long and 20.5 mm external diameter of the sleeve,) which transmits both 254 and 185 nm

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light. The electric input of the lamp is 15 W and the effective power-output is 4.0 W in the UV range. The emitted photon flow of the light sources was measured by potassium ferrioxalate actinometry. The photon flow of the 254 nm component was found to be 3.45(±0.09)×10-5 einstein s-1. The low-pressure mercury vapour lamp with envelope (320 mm long and 28 mm internal diameter) was centered in the water-cooled, tubular glass reactor (length 340 mm, inner diameter 46 mm). Air (375 cm3 min-1) was driven through the solution during the time of irradiation. The thermostated (25 ± 0.5 °C) solution (500 cm3) was circulated (375 cm3 min-1) continuously and stirred with a magnetic stirrer bar in the reservoir. The kinetic measurements were commenced by switching on the light source. The concentration of diuron, monuron and fenuron was measured with an HPLC system consisting of a Merck-Hitachi L-7100 low-pressure gradient pump equipped with a MerckHitachi L-4250 UV-Vis detector (λ = 210 nm) applying a Lichrospher RP 18 column and acetonitrile/water (50/50) mixture as eluent. In our work toxicology measurements were carried out by different ways. These tests were done to determine the toxicity of the samples after the 0, 12.5, 25, 50, 75 and 100% decomposition of parent compound. Two standard toxicity assays were applied for aquatic toxicity assessment: Dapnia magna (ISO 6341, 1996) and Pseudokirchneriella subcapitata (ISO 8692, 2004). The Dapnia magna 24-48 acute immobilisation tests were conducted according to internationaly accepted Standard Methods (OECD Guideline 201 and ISO 6341; Daphtoxkit FTM magna). The tests are performed using neonates which are hatched in about three days from eggs at 20-22 °C, under continuous illumination of 6000 lux. Immobility at 24 h and 48 h is the bioassay endpoint, assumed to be equivalent with the mortality. The microalgae growth inhibitory tests with Pseudokirchneriella subcapitata were conducted according to internationally accepted Standard Methods (OECD Guideline 201 and ISO 8692; Algaltoxkit FTM). In this test the optical density at 670 nm is used to measure the algal growth inhibition. The Ames genotoxicity test employs several histidine auxotrophic strains of Salmonella typhimurium, which have been selected on the bases of their sensitivity to distinct types of mutagens. These reverse mutation tests are performed by mixing the test substance solution and the tester strain together in a rich liquid medium, which contains only small amounts of histidine. Histidine permits the inoculated test organism to undergo a limited number of divisions, but it is insufficient to permit normal growth. However, if the strain undergoes a reverse mutation, (spontaneous, or induced by the test substance or a positive control material) the organism no longer requires histidine to grow and can produce visible revertant colonies after spreading the treated cell suspension on the surface of minimal medium. RESULTS AND DISCUSSION O H3C H3C

Cl

C N

N H

Diuron

O

O Cl

H3C H3C

H3C

C N

N

Cl

H3C

C N

H

Monuron

N H

Fenuron

Figure 1.The structure of the investigated compounds The structure of the investigated compounds is shown in Figure 1. The first step of this work was the determination of the molar absorptivity of the target substances at 254 nm. Because of the high molar absorptivity of diuron and monuron at 254 nm (15 000 mol-1 dm3 cm-1 and 12 500 mol-1 dm3 cm-1), the UV photolysis is a quite efficient method for their degradation. On

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the other hand, the rate of transformation of monuron is about two times higher than that of diuron, opposite that the molar absorptivity of diuron is higher. Both, molar absorptivity (4 500 mol-1 dm3 cm-1) and the rate of transformation of fenuron is much smaller than that of the chlorinated phenyl urea pesticides (Fig. 2). The kinetic measurements were achieved both in unbuffered and buffered solutions. Phosphate buffer has no effect on the rate of transformation and the formation of intermediates. (Fig. 2) 1.8

-4

c (×10-5 M) M) c (×10

1.5

z

diuron

„ monuron

1.2

S fenuron

0.9 0.6 0.3 0.0 0.0

2.0

4.0

6.0

8.0

3

(×10 3 s) t t(× 10 s)

Figure 2. Kinetic curves determined in buffered (phosphate buffer, pH = 7.2, empty symbols) and unbuffered solutions (full symbols) Using Daphtoxkit FTM Magna ecotoxicology test, the mortality rate of Daphnia Magna was 100% at the initial concentration (1,7×10-4 M) of diuron and monuron and decreased with decrease of the concentration (Fig. 3A). Fenuron has no effect on the Daphnia Magna even at the highest concentration (1,7×10-4 M). In the case of the diuron and monuron, the toxicity decreased during the UV treatment. At the same time, in the case of the fenuron, the toxicity of the solution strongly increased likely because of the formation of highly toxic intermediates (Fig. 3B). The time dependence of the mortality rate suggest that the(se) highly toxic intermediate(s) can not be decomposed due to the 254 nm UV light irradiation. 100

100

z diuron

B

80

„ monuron

Pusztulás (%) (%) Mortality

Mortality Pusztulás(%) (%)

80 60 40 20

60 40

z: diuron „: monuron S: fenuron

20

A

0

0 0.0

0.5

1.0

1.5

0

2.0

20

40

60

80

100

elbomlott peszticid hatóanyag (%) decomposed pesticide (%)

×10 M)M) c c( (×10 -4 -4

Figure 3. The effect of the initial concentration of pesticide on the mortality of Daphnia Magna (A) and the change of the mortality versus the degree of the decomposition of pesticides at 1,7×10-4 M initial concentration (B) The results of the Algaltoxkit FTM test showed that the Pseudokirchneriella Subcapitata is much more sensitive on the presence of these pesticides, than Daphnia Magna. The lowest investigated concentration (1,1×10-5 M) of each investigated pesticide inhibited completely the growing of algal. In the cases of the UV treated samples, the ecotoxicology effect decreased slightly until that time, the target substances decomposed completely (Fig. 4).

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algal alga growth inhibition (%) növekedés gátlása (%)

100 80 60 40

z: diuron „: monuron S: fenuron

20 0 0

20

40

60

80

100

decomposed pesticide (%)(%) elbomlott peszticid hatóanyag

Figure 4. The algal growth inhibition versus the degree of the decomposition of pesticides at 1,7×10-4 M initial concentration 250

250

250

TA 1537 TA 98 150 100 50 0

200

TA 1537

TA 1535

200

R e ve rta n t/p late

TA 1535

R evertants/plate

R evertan t/p late

200

TA 1537 TA 98 150 100 50 0

0

0

12.5

25

50

75

decomposed diuron (%)

90

100

TA 1535 TA 98

150 100 50 0

0

0

12.5

25

50

75

90

decomposed monuron (%)

100

0

0

12.5

25

50

75

90

100

decomposed fenuron (%)

Figure 5. Results of the Ames tests in the case of the decomposition of diuron (A), monuron (B) and fenuron (C) The results of the Ames tests (Fig 5) suggests that, during the UV initiated transformation the genotoxicology effect of the formed multicomponent solutions showed maximum type curves. The treated solution has no further genotoxicology effect after the total decomposition of the target substance. ACKNOWLEDGEMENT This work was financially supported by the NKFP DA_ THERM TECH_08_A4 and European Regional Development Foundation TÁMOP-4.2.1/B-09/1/KONV-2010-0005. This document has been produced with the financial assistance of the European Union (Project HU-SRB/0901/121/116 OCEEFPTRWR Optimization of Cost Effective and Environmentally Friendly Procedures for Treatment of Regional Water Resources). The contents of this document are the sole responsibility of the University of Szeged and can under no circumstances be regarded as reflecting the position of the European Union and/or the Managing Authority. LIST OF REFERENCES [1] Giacomazzi S, Cochet N, Chemosphere, 56, 1021-1032., 2004. [2] Chiron, S., Fernandez-Alba, A., Rodriguez, A., Garcia-Calvo, E., Wat. Res., 34,2, 366377, 2000. [3] Stackelberg, P.E., Gibs, J., Furlong, E.T., Meyer, M.T., Zaugg, S.D., Lippincott, R.L., Sci. Total. Environ., 377, 255-272, 2007. [4] Scweinsberg, F., Abke, W., Rieth, K., Rohmann, U., Zullei-Seibert, N., Toxicology Lett., 107, 201-205, 1999.

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ALGADISK- INTRODUCTION OF A STARTING FP7 PROJECT (286887) Petra Sebestyén, Ágnes Dergez, Ákos Koós, Attila Wootsch, PhD, Péter Kesserű, PhD, István Kiss, PhD Bay Zoltán Foundation for Applied Research Institute for Biotechnology, Derkovits fasor 2. H-6726 Szeged, Hungary e-mail: [email protected] ABSTRACT Microalgae could substitute crops in biofuel production due to their high biomass productivity and lipid content, although none of the existing systems has been enough cost-effective to compete fossil fuels or biodiesel produced from plants so far. Nowadays, microalgae production is usually carried out in open pond and closed photobioreactors; however, these technologies have some limiting factors including high water demand, contamination, large surface area requirements, self-shading and low productivity. ALGADISK project could provide a technology that gives solutions for these limiting factors of open pond and closed photobioreactors. The project includes the selection of microalgae species with high lipid content and examining and determining their ideal growth and operational conditions, construction an energetically efficient reactor system with automatic harvesting system, and a computer based tool in order to optimize operational conditions and estimate profitability, furthermore reducing water demand, reaching at least 20g/l algal biomass. INTRODUCTION During the last few decades the consumption of fossil fuels has increased greatly which resulted for instant in high fuel prices and in an increased level of CO2 emission. Due to the different global environmental programmes (e.g. Kyoto Protocol) the production of biofuels was approximately 8000 kton in EU member countries in 2007 which was 2,6% of the total fuel consumption [1]. Major part of biofuels is produced from crops which can provide a competitive price and a reduced CO2 emissions, however, it competes with food crops for arable lands and their biomass yields are not high enough. To avoid the rise of the prices of food crops, algae could substitute plants in biofuel production due to their higher productivity than crops and their high level lipid content, moreover, algae can be grown on agriculturally unsuitable lands [2]. Besides biodiesel production, algae are well known producers of rare polyunsaturated fatty acids and carotinoides [3], which are valuable nutrients for humans and the produced biomass can be then converted to several end-products (e.g. ethanol, hydrogen etc.) as it is shown on the Fig. 1. Algae can be either autotrophic or heterotrophic organisms. Autotrophic algae are able to transform light to biomass via photosynthesis and they only require inorganic compounds, thus they are regarded as a potential solution for reducing CO2 emission. However, heterotrophic algae only grow in the presence of organic nutrients. [4]

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Fig. 1. Processes for algal biomass conversion [5] For algae biomass production, two systems are used worldwide: open pond and closed photobioreactors. Open pond systems are artificial ponds where air is CO2 source, the environment is highly selective to prevent contamination and the broth is mixed with paddlewheels. Besides its benefits like low energy input, easy maintenance and cleaning, relatively high production, many limiting factors are known as changes in temperature and light intensity, CO2 deficiencies, evaporation and only a few alga species are suitable for this production technology [3]. Some of these problems can be overcome using closed photobioreactors. One of its most important benefits that contamination is prevented. Cost of harvesting can be reduced because of the high cell density, however, the overall cost of closed systems are higher than of open ponds. Although these production methods are commonly used, they are still facing many difficulties such as expensive installation, low productivity, large surface area and high water demand. The aim of ALGADISK project is to develop a microalgae production technology for efficient biodiesel production, which is able to provide solutions for the limitation factors of the currently applied technologies and can be profitable in small-scale, occupies a little space and can be installed without highly trained end-users. ABOUT ALGADISK PROJECT To realize this plan, an FP7 project would be generated, which include three SME (Small and Medium Enterprises) Associations, four RTD (Research and Technological Development) and five other SME partners (Table 1.). The SME and SME Associations are the beneficiaries of the project and the RTD partners will develop the ALGADISK system.

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Table 1. Members of ALGADISK project Project members Acronyms European Biomass EUBIA Industry Association (Italy)

Partnership type SME-Association

Responsibilities system specification according to the needs of members focus on the need of SMEs in the food and feed sector training activities, IPR management mechanical engineering and construction tasks reactor design, construction, validation alga selection, develop sensors and monitoring system mechanical, electrical design of reactor, installation

Spanish Confederation of Compound Feed Producer

CESFAC (Spain)

SME-Association

FUNDACIÓN CESFAC

FC (Spain)

SME-Association

OLAJGÉP-Tec Kft.

OTEC (Hungary)

Other partners

Biogas Fuel Cell SA

BFC (Spain)

Other partners

ONVIDA GmbH

ONVIDA (Germany)

Other partners

Umwelt-Technik Ltd

UTECH (Hungary)

Other partners

CAG (Turkey)

Other partners

waste management, pollution monitoring

MFKK Invention and Research Center Services

MFKK (Hungary)

RTD performers

prediction software development, prototype construction

Cranfield University

CRAN (United Kingdom)

RTD performers

surface development

Wageningen University

WU (Netherlands)

RTD performers

selection of alga growth conditions, validating the system

Bay Zoltán Foundation for Applied Research

BAYBIO (Hungary)

RTD performers

alga selection, growth condition optimalization

CAGLAR DOGAL ÜRÜNLER Ltd

The main objectives and steps of ALGADISK project are the following ones: • selection of algae which grows preferably on surface and have high lipid content • developing lightweight, inexpensive and biocompatible surfaces for algae growth • development of automatic harvesting system • reducing water requirements meanwhile reaching at least 20g/l algae concentration by using bio-film technology • designing a reactor capable to install within a week • design and construction of a reactor system integrated with renewable energy sources • developing a computer based tool for users to optimize operational conditions and to estimate profitability • optimizing and validating the reactor prototypes under realistic conditions The objectives of ALGADISK project from scientific view are: • examining the CO2 uptake from liquid and gas phases

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• calculating the energy input and output for different alga species • determining the engineering parameters of the reactor such as mixing parameters, mean liquid residence time etc. • determining optimal living conditions for algae With this system the amount of used water can be reduced compared to open ponds or photobioreactors, it can be applied either open or closed and it turns the drawback of wall growth into an advantage. CONCLUSIONS • During this project a new, efficient, reliable, predictable and scalable system will be created. • The technology described in ALGADISK project could fulfill the needs of European market where arable land space and capital are limited. LIST OF REFERENCES [1] http://ec.europa.eu/energy/publications/statistics/statistics_en.htm [2] Scott, S. A., Davey, M. P., Dennis, J. S., Horst, I., Howe, C. J., Lea-Smith, D. J., Smith, A. G. (2010) Biodiesel from algae: challenges and prospects. Current Opinion in Biotechnology. 21:277-286 [3] Borowitzka, M. A. (1999) Commercial production of microalgae: ponds, tanks, tubes and fermenters. Journal of Biotechnology. 70. p. 313-321 [4] Lee R. E.(1980) Phycology. New York: Cambridge University Press [5] Tsukahara K., Sawayama S. (2005) Liquid fuel production using microalgae. Journal of the Japan Petroleum Institute. 48. p. 251-259

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VACUUM-ULTRAVIOLET PHOTOLYSIS OF NON-STEROIDAL ANTI-INFLAMMATORY DRUGS Eszter Arany1, Sandra Cerrone2, Rita Katalin Szabó1, Tünde Alapi3, Krisztina GajdaSchrantz3, András Dombi1 1

Institute of Material Sciences and Engineering, University of Szeged, 6720 Szeged, Tisza Lajos krt. 103, Hungary; 2 Faculty of Mechanical and Process Engineering, Hochschule Furtwangen University, 78054 Villingen-Schwenningen, Jakob-Kienzle Str. 17, Germany; 3 Department of Inorganic and Analytical Chemistry, University of Szeged, 6720 Szeged, Dóm tér 7, Hungary. Email: [email protected] ABSTRACT Non-steroidal anti-inflammatory drugs (NSAIDs) ibuprofen, ketoprofen, diclofenac and naproxen are detected even in natural waters. Their degradation was achieved through the generation of reactive oxygen containing species (ROS, such as •OH, HO2• and •O2-) by using a xenon excimer lamp (λmax. = 172 ± 14 nm). The effect of the initial drug concentration, dissolved molecular oxygen, methanol as •OH scavenger and the effect of these pharmaceuticals on each other were investigated. According to the results, not only the reactions based on •OH, but the reactions with other ROS and excited water molecules should also be taken under consideration for the interpretation of the transformation of the four investigated NSAIDs. INTRODUCTION The drugs investigated in this work, ibuprofen (IBU), ketoprofen (KETO), diclofenac (DICL) and naproxen (NAP) (Fig. 1) belong to the group of non-steroidal anti-inflammatory drugs (NSAIDs). Due to the improper annihilation and disposal of these medicines they are frequently detected in the aquatic environment. The maximal detected concentration in natural waters are 2.8 μg dm-3 for IBU, 0.99 μg dm-3 for KETO, 1.2 μg dm-3 for DICL and 1.5 μg dm3 for NAP [1-3]. a

b

c

d

Figure 1. The chemical structure of a) IBU, b) KETO, c) DICL and d) NAP 64

The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Therefore, new water treatment techniques are needed, which are more efficient than the conventional ones in the elimination of such persistent chemicals. The methods based on the generation of various reactive oxygen containing species (ROS, mainly •OH), like vacuumultraviolet (VUV) photolysis are promising: they can mineralize effectively the contaminant molecules [4]. Water is the main absorber of the VUV light, resulting in excited water molecules (H2O*). Hydrogen atoms and hydroxyl radicals are formed via homolytic bond dissociation with a quantum yield of: ΦH2O172 nm = 0.42 ± 0.04 [5]. Dissolved molecular oxygen might prevent the recombination of these radicals by scavenging H• (Scheme 1). H2O

172 nm

ΦH2O172 nm = 0.42 ± 0.04 H2O* (H• + •OH)

H2O

O2 pKa = 4.8 HO2•

•O2- + H+

Scheme 1. The VUV photolysis of water The formed HO2• as well as its conjugate base pair, the •O2- might react with the NSAIDs or with •OH (Table 1). The first reaction increases, while the second one decreases the rate of transformation of the target molecules. The degradation rate of the contaminants depends greatly on the reaction rate coefficients (k) and on the concentrations of the various species involved in these reactions. Table 1. The reaction rate coefficients (k) of the four NSAIDs and some radicals with •OH substrate k (×109 mol-1 dm3 cm-1) reference HO2• 6.6 [6] •O2 10 [7] IBU 7.4 [8] KETO 8.4 [9] DICL 18 [8] NAP 24 [10] MATERIALS and METHODS All of the used chemicals were of analytical purity (IBU, KETO, DICL sodium salt: SigmaAldrich, ≥ 98%, NAP: Fluka, 98%, acetic acid: Sigma-Aldrich, ≥ 99%, methanol (MeOH), acetonitrile: Scharlau, HPLC-grade). The solutions of the NSAIDs were prepared using MilliQ water produced by MILLIPORE Synergy185 (resistivity: 18 MΩ cm-1). The experiments were carried out in a circulated system (flow rate: 375 cm3 min−1), where a xenon excimer lamp (λmax. = 172 ± 14 nm, P = 20 W, Osram) was centered in a water-cooled, double-walled tubular glass reactor. The irradiated solutions (250 cm3) were thermostated at 25°C. The effect of dissolved molecular oxygen was investigated by saturating the irradiated solution with N2, air or O2 (gas flow rate: 855 cm3 min−1). During the kinetic experiments the samples were analyzed using an Agilent 1100 type HPLC equipped with a diode array detector. An eluent of a 50-50% mixture of 1% aqueous acetic acid and acetonitrile was used. The separation of the degradation products was carried out on a C18 (LichroCHART 125-4.5 µm) Agilent column at 0.8 cm3 min-1 flow rate of eluent. 65

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RESULTS Although the k values of the reactions of the four NSAIDs and •OH decrease in the order: NAP > DICL > KETO > IBU, the initial transformation rates (r0) follow the order: KETO > IBU ≈ DICL > NAP (Table 1 vs. Fig. 2.a). Therefore, it seems that the transformation of these drugs is not determined only by •OH. a

b

12

r0 (×10-7 mol dm-3 s-1)

r0 (×10-7 mol dm-3 s-1)

12 10 8 6 4 2

10 8 6 4 2 0

0 0

0.2

0.4

0.6 -4

0.8

N02

1

-3

20 air

40

60

cO2 (%)

c0 (×10 mol dm )

80

100 O2

Figure 2. The initial transformation rates (r0) of KETO (○), DICL (■), IBU (∆) and NAP (♦) a) vs. their initial concentration, in the presence of oxygen, b) vs. the concentration of dissolved molecular oxygen, c0 being 1×10-4 mol dm-3 Dissolved molecular oxygen does not have the same effect on pharmaceuticals having different chemical structure (Fig. 1 vs. Fig. 2.b). It decreases strongly the r0 of NAP, but increases that of IBU and KET. At the same time it has no effect on the rate of transformation of DICL. This is likely because of the way of transformation of the NSAIDs depends greatly on the structure of the target molecule. The presence of another organic substrate causes a decrease of the r0 of the target substance likely because of the competition for the reactive species (Table 2). MeOH, the commonly used •OH scavenger could produce the same effect only in an around 1000 times higher concentration than NSAIDs, although, the k of the reaction of MeOH with •OH is only with one order of magnitude lower than the values listed in Table 1 (k = 1.0×109 mol-1 dm3 s1 [11]). Additionally, dissolved molecular oxygen strongly enhanced the decrease of r0 in the case of IBU and KETO. Consequently, besides the •OH based reactions, the reactions with other formed ROS and excited water molecules might also have a relative high contribution to the transformation of these target substances during the VUV photolysis of their aqueous solution. Table 2. The initial transformation rates of the four NSAIDs (c0 = 1×10-4 mol dm-3) affected by the presence of methanol (c0 = 0.1 or 1 mol dm-3) or another drug (c0 = 1×10-4 mol dm-3) r0 (×10-7 mol dm-3 s-1) substrate - IBU KETO DICL NAP 0.1 mol dm-3 MeOH 1 mol dm-3 MeOH IBU 6.8 1.8 2.7 KETO 10.3 5.9 7.4 7.5 8.0 4.0 DICL 7.2 3.3 6.0 3.6 1.9 NAP 4.5 3.2 2.5 3.0 1.7

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CONCLUSIONS Dissolved molecular oxygen has various effects on the VUV photolysis of NSAIDs having different molecular structure. The transformation of the NSAIDs can not be interpreted only with the reactions based on •OH, the reactions with other ROS and excited water molecules should also be taken under consideration. ACKNOWLEDGEMENTS The authors express their gratitude to the Hungarian Research Foundation (NKTH-OTKA CK 80193) and the European Regional Development Fund (TÁMOP-4.2.1/B-09/1/KONV-20100005). This document has been produced with the financial assistance of the European Union (Project HU-SRB/0901/121/116 OCEEFPTRWR Optimization of Cost Effective and Environmentally Friendly Procedures for Treatment of Regional Water Resources). The contents of this document are the sole responsibility of the University of Szeged and can under no circumstances be regarded as reflecting the position of the European Union and/or the Managing Authority. LIST OF REFERENCES [1] Ternes T.A. (1998). Occurrence of drugs in German sewage treatment plants and rivers. Water Research. 32, p. 3245-3260. [2] la Farré M., Ferrer I., Ginebreda A., Figueras M., Olivella L., Tirapu L., Vilanova M., Barceló D. (2001). Determination of drugs in surface water and wastewater samples by liquid chromatography– mass spectrometry: methods and preliminary results including toxicity studies with Vibrio fischeri. Journal of Chromatography, A. 938, p. 187–197. [3] Fernández C., González-Doncel M., Pro J., Carbonell G., Tarazona J.V. (2010). Occurrence of pharmaceutically active compounds in surface waters of the Henares-Jarama-Tajo River system (Madrid, Spain) and a potential risk characterization. Science of the Total Environment. 408, p. 543551 [4] Oppenländer T. (Eds.). Photochemical purification of water and air. 2003. Weinheim. WileyVCH. [5] Heit G., Neuner A., Saugy P.-Y., Braun A.M. (1998). Vacuum-UV (172 nm) actinometry. The quantum yield of the photolysis of water. Journal of Physical Chemistry A. 102, p. 5551-5561. [6] Sehested K., Rasmussen O.L., Fricke H. (1968). Rate constants of OH with HO2, O2-, and H2O2+ from hydrogen peroxide formation in pulse-irradiated oxygenated water. Journal of Physical Chemistry. 72, p. 626-631. [7] Christensen H., Sehested K., Bjergbakke E. (1989). Radiolysis of reactor water: Reaction of hydroxyl radicals with superoxide (O2-). Water Chemistry of Nuclear Reactor Systems. 5, p. 141-144. [8] Huber M.M., Canonica S., Park G.-Y., von Gunten U. (2003). Oxidation of pharmaceuticals during ozonation and Advanced Oxidation Processes. Environmental Science & Technology. 37, p. 10161024. [9] Real F.J., Benitez F.J., Acero J.L., Sagasti J.J.P., Casas F. (2009). Kinetics of chemical oxidation of the pharmaceuticals primidone, ketoprofen, and diatrizoate in ultrapure and natural waters. Industrial & Engineering Chemistry Research. 48, p. 3380-3388. [10] Packer J.L., Werner J.J., Latch D.E., McNeill K., Arnold W.A. (2003). Photochemical fate of pharmaceuticals in the environment: Naproxen, diclofenac, clofibric acid, and ibuprofen. Aquatic Sciences. 65, p. 342-351. [11] Buxton G.V., Greenstock C.L., Helman W.P., Ross A.B. (1988). Critical review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (•OH/•O-) in aqueous solution. Journal of Physical Chemistry Reference Data. 17, p. 513 – 886.

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INFLUENCE OF PRECURSORS ON STRUCTURE AND MAGNETIC PROPERTIES OF CuFe2O4 OBTAINED BY COPRECIPITATION Florina Stefania Rus1 *, Paulina Vlazan2, Grozescu Ioan1,2, Novaconi Dan2 1 2

Politehnica” University of Timisoara, Piata Victoriei 2, 300006, Timisoara, Romania Institute for Research and Development in Electrochemistry and Condensed Matter, P. Andronescu Street, No.1,300224 Timisoara, Romania, e-mail: [email protected]

ABSTRACT Nanoparticles of copper ferrites were obtained by co-precipitation method using two precursors Cu(CH3COO)2 and Cu(OH)2 with FeSO4·7H2O. In this paper, we try to demonstrate the influence of precursors on structure and magnetic properties of CuFe2O4 obtained by co-precipitation allow the preparation of high reactive ferrite nanoparticles whose composition, microstructure, size and properties can be rigorously controlled in order to obtain the special requirements of various advanced applications. INTRODUCTION Copper ferrite (CuFe2O4) is one of the important spinel ferrites MFe2O4 because it exhibits phase transitions, changes semiconducting properties, shows electrical switching and tetragonal variation when treated under different conditions in addition to interesting magnetic and electrical properties with chemical and thermal stabilities[1]. The method of preparation plays a very important role in determining the chemical, structural and magnetic properties of spinel ferrites [2]. The essential requirements of obtaining well controlled uniformity and high-purity materials encouraged the development of wet chemical methods, such as coprecipitation[3,4], hydro/solvothermal synthesis[5-6], micro-emulsion[7] and sol–gel technique[8]. It is used in the wide range of applications in gas sensing [9], catalytic applications[10], Li ion batteries[11] high density magneto-optic recording devices, colour imaging, bio-processing, magnetic refrigeration and ferrofluids, for the removal of acid orange II and catalytic regeneration[12-13]. MATERIALS and METHODS In this paper we synthesized two fine copper ferrite particles using co-precipitation technique, using for precursors Cu(CH3COO)2 and Cu(OH)2with FeSO4·7H2O. The copper ferrite particles were prepared by regular co-precipitation as follows, FeSO4·7H2O (purity 99%) with Cu(CH3COO)2 (purity 99%)and FeSO4·7H2O with Cu(OH)2were taken in a Cu/Fe = 1:2 mole ratio. The materials were dissolved in distilled and de-ionized water. The two solutions of Cu(CH3COO)2 and FeSO4·7H2O(P5) were mixed together on magnetic stirrer with continuous stirring at a moderate speed for 30 minutes and the same way the second solution Cu(OH)2 with FeSO4·7H2O(P6). In another beaker, solution of 1M NaOH was prepared. After this addition of NaOH up to pH 12 at continuous stirring a dark precipitate was obtained. The precipitate was filtered, washed with deionized water and then dried at 60cC for 4h. A scanning electron microscope SEM was used for observing the sample morphology spectra

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

were analyzed using a FEI, Inspect-S microscope. Elemental X-ray powder diffraction was performed at room temperature (20±2°C) on the PANalytical X’Pert Pro MPD diffractometer using CuKα radiation (λ=1.54 Å) between 20 and 100° (2θ) with an integrated step scan of 0.016° (2θ). Magnetic studies were carried out using a conventional induction method [15], in AC magnetic fields up to 4 kOe RESULTS Figure 1 presents the X-ray diffraction pattern of the powders synthesized by co-precipitation method (P5) and (P6).

Fig. 1. XRD patterns of the CuFe2O4 samples

The diffraction peaks are intense, revealing a good crystallization degree for copper ferrite. From the XRD patterns, the average crystalline sizes for the spinel phase were estimated from the broadening of the strongest diffraction peak using Scherrer equation given by: D =Kλ/βcosθβ with β2=βa2-βb2 (1) where D is the average crystallite size, K is the shape factor (we take K=0.9), λ is the X-ray wavelength used, β is the measure of the broadening of the peak in a diffraction pattern, βa and βb are the full-width at half-maximum of the XRD line of the sample of a standard specimen respectively at around the same Bragg's angle and θβ is the Bragg's angle in degree. Using this relation (eq. (1)), the average crystallite sizes, for the samples using a (3 1 1) reflection have been estimated for sample P5=21.8nm and for the sample P6=14nm The SEM images from Fig. 2(a) shown low degree of agglomeration that in Fig 2(b)

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

Fig. 2 (a)

Fig. 2 (b)

Fig. 2.(a) and (b) SEM micrographs of the CuFe2O4 sample The scanning electron microscopy micrographs for P5 obtained showed very fine and homogenous pseudo-cubic copper ferrite,and P6 showed agglomerations of layers copper ferrite.

Fig. 3. Variation of magnetization with applied magnetic field for CuFe2O4 samples

The magnetic measurements made on the samples indicate a small coercitive field that presents almoust superparamagnetic behavior and the specific saturation magnetization for P5 is 49.4emu/g and for P6 is 47.8emu/g. CONCLUSIONS Nanoparticles of copper ferrites were obtained by co-precipitation method using two different precursors of Cu we established the following characteristics: • The precursors have strongly influenced the morphology, crystallite size, microstructures. • Saturation magnetization values for P5-49.4, for P6-47.8 and magnetic coercivity smaller for sample P5-57Oe and for P6-60Oe. • The crystallite size for sample P5 is 21.8nm and for the sample P6 is 14nm. • The sample P5 very fine and homogenous pseudo-cubic copper ferrite and P6 presents agglomerations of layers copper ferrite. Acknoledgements This work is supported by the strategic grant POSDRU ID77265 (2010), co-financed by the European Social Fund – Investing in People, within the Sectorial Operational Programme Human Resources Development 2007-2013 and project ″Development of composite magneto dielectric nanostructures in creation of intelligent shield for pronounced absorption microwaves ″ at the National Research&Development Institute for Electrochemistry and

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Condensed Matter, Department of Condensed Matter Research and was support by Minister of Education and Research. LIST OF REFERENCES [1] Philippe Tailhades, Corine Bonningue, Abel Rousset, Laurence Bouet, Isabelle Pasquet, Stéphane Lebrun (1996). About the interesting properties of mixed-valence defect spinel ferrites for mass storage media. Journal of Magnetism and Magnetic Materials, Volume 193, Issues 1-3,March 1999, Pages 148-151 [2] N.M. Deraz (2010). Size and crystallinity-dependent magnetic properties of copper ferrite nano-particles, Journal of Alloys and Compounds, Volume 501, Issue 2, Pages 317-325 [3] Sunil Rohilla, Sushil Kumar, P. Aghamkar, S. Sunder, A. Agarwal (2011). Investigations on structural and magnetic properties of cobalt ferrite/silica nanocomposites prepared by the coprecipitation method. Journal of Magnetism and Magnetic materials applied Microbiology and Biotechnology. Pages 897-902 [4] K. Maaza, Arif Mumtaza, S.K. Hasanaina, Abdullah Ceylanb. (2007). Synthesis and Magnetic properties of cobalt ferrite (CoFe2O4) nanoparticles prepared by wet chemical route. Journal of Magnetism and Magnetic Materials 308 289–295 [5] Xiaoling Hu, Ping Guan and Xin Yan. (2004) .Hydrothermal synthesis of nano-meter microporous zinc ferrite. Particuology Vol. 2, No. 3, 135-137 [6] S. Yáñez-Vilar, M. Sánchez-Andújar, C. Gómez-Aguirre, J. Mira, M.A. SeñarísRodríguez, S. Castro-García. (2009). A simple solvothermal synthesis of MFe2O4(M=Mn, Co and Ni) nanoparticles. Journal of Solid State Chemistry Volume 182, Issue 10, P2685-2690 [7] Vinod Pillai, Promod Kumar, Manu S. Multani and Dinesh O. Shah. (1993). Structure and magnetic properties of barium ferrite synthesized using microemulsion processing. Colloids and Surfaces A:Physicochemical and Engineering Aspects Volume 80, Issue 1, Pages 69-75 [8] R.B. Jotaniaa,_, R.B. Khomaneb, C.C. Chauhana, S.K. Menonc, B.D. Kulkarnib. (2008) Synthesis and magnetic properties of barium–calcium hexaferrite prepared by sol-gel and microemulsion techniques. Journal of Magnetism and Magnetic Materials 320 1095–1101 [9] A. Chapelle, F. Oudrhiri-Hassani, L. Presmanes, A. Barnabé (2010).CO2 sensing properties of semiconducting copper oxide and spinel ferrite nanocomposite thin film. Applied Surface Science 256 (2010) 4715–4719 [10] M.M.Rashad,R.M. Mohamed, M.A. Ibrahim,L.F.M. Ismail, E.A, Abdel-Aal. (2011) . Magnetic and catalytic properties of cubic CuFe2O4 nanopowder synthesized from secondary resources Advanced Powder Technology doi:10.1016/j.apt.2011.04.005 [11] R. Kalai Selvan N. Kalaiselvi, C.O. Augustin, C.H. Doh, C. Sanjeeviraja (2006). CuFe2O4/SnO2 nanocomposites as anodes for Li-ion batteries. Journal of Power Sources 157 522–527 [12] Anjali Verma, M.I. Alam, Ratnamala Chatterjee, T.C. Goe, R.G. Mendiratta. (2009) Development of a new soft ferrite core for power applications. Journal of Magnetism and Magnetic Materials 300 (2006) 500–505 [13] Gaosheng Zhang, Jiuhui Qu, Huijuan Liu, Adrienne T. Cooper, Rongcheng Wu. (2007) CuFe2O4/activated carbon composite: A novel magnetic adsorbent for the removal of acid orange II and catalytic regeneration. Chemosphere 68 1058–1066 [14] I. Mihalca, A. Ercuta, C. Ionascu, (2003), Sensors and Actuators A, 106, 61.

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PECULIARITIES OF THE COMPARATIVE METALLOGRAMS OF THE UROCONCREMENTS HAVING URATES AS DOMINANT COMPONENT AND PHOSPHATES AS DOMINANT COMPONENT Avacovici Adina-Elena1, Cumpănaş Alin 2, Anca Lucia3, Ghibu George-Daniel4, Baltă Cornel5 , Garban Zeno5 1.Faculty of Industrial Chemistry and Environmental Engineering, University Politehnica Timişoara, Piaţa Victoriei Nr. 2, RO-300006 Timişoara, Roumania; 2. University Clinic of Urology, Faculty of Medicine, University of Medicine and Pharmacy “Victor Babeş” Timişoara, Blvd. I. Bulbuca Nr. 156, RO-300723 Timişoara, Roumania; 3. Medical Department of S.C. “CaliVita” International, Calea Aviatorilor Nr. 18, RO307200 Ghiroda, Jud. Timis, Roumania; 4. Department of Radiology, County Clinic Hospital No.2, Str. G. Dima No.5, RO-300079 Timişoara, Roumania; 5. Department of Biochemistry and Molecular Biology, Faculty of Food Products Technology, University of Agricultural Sciences and Veterinary Medicine of Banat, Calea Aradului Nr. 119, RO-300645, Timişoara, Roumania

ABSTRACT Investigations were made on uroconcrements collected from two groups of subjects (patients) with kidney stones and admitted in the hospital. In the first step, using Fourier Transformed Infrared Spectroscopy (FT-IR) the types of uroconcrements were defined. Further on, a limited number of uroconcrements were analyzed by means of atomic absorption spectroscopy (AAS) in order to determine the concentration of the some alkaline (Na, K) and alkaline-earth (Ca, Mg) metals in their composition. From the first group only the uroconcrements having urates as dominant components and from the second group only the uroconcrements having phosphates as dominant components were selected. The comparison of the obtained metallograms revealed aspects about the types of lithiasis and their specificity. Key words : metallograms, urates lithiasis and phosphates lithiasis INTRODUCTION Metals are important components of the human organism which are neither produced nor destroyed by the organism and are present in our environment, i.e. food, water, air, soil. In the etiopathogeny of urolithiasis metals play a key role and may intervene either indirectly as effectors (inhibitors-activators) of metabolic processes, or directly as substituents engaged in competing interactions owing to the difference in the solubility products of oxalic, phosphatic salts etc. (Berg et al., 1990; Haraguchi, 2004) The urolithogenesis begins with the appearance of so-called “starters” or “primers” resulted by precipitative mechanisms, involving the presence of a single specific anion (e.g. urates, phosphates, oxalates) or coprecipitative ones involving two or more anions. These anionic (organic and inorganic) compounds may bond with: metallic ions; non-metallic ions (NH4+); non-ionic compounds. MATERIALS AND METHODS The analytical investigations were made on the surgically removed or spontaneously eliminated urinary calculi collected from two groups of subjects (patients) admitted in the University Clinic of Urology Timişoara in different periods. By means of Fourier Transformed Infrared Spectroscopy (FT-IR), using a JASCO FT-IR/410 type apparatus (Channa et al., 2007) in the 400-4000 cm-1 wavenumber range at 4 cm-1 resolution, the qualitative composition of each calculi was determined. In a preliminary stage of the study the standard IR spectra of the chemically pure compounds present in calculi (organic - oxalic

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

acid, uric acid, xanthine, cystine, cholesterol and inorganic - phosphates, carbonates) were recorded in order to establish the type of urolithiasis. From the first group of 276 subjects there were selected only the uroconcrements having urates as dominant component (noted nu) - 84 cases. From the second group of 237 subjects there were selected only the uroconcrements having phosphates as dominant component (noted np) – 133 cases. The selected uroconcrements were analyzed by means of atomic absorption spectroscopy (AAS) and the concentrations of the following metals were determined : Na, K, Ca, Mg. Investigations were performed by a PYE UNICAM series Sp 1900 spectrophotometer in the spectral range of λ = 189-855 nm. The obtained analytical data were processed statistically : mean values (X) and standard deviations (SD) have been calculated for each metal (expressed as μg/g calculi). RESULTS AND DISCUSSIONS The human urine is a metastable solution which contains beside nitrogenous compounds, protein, polysaccharides, organic acids and also anions and inorganic cations (Na, K, Ca, Mg, Zn, Cu, Mn, Fe). These ions play an important role in the lithogenic processes. The concentration of these elements may vary due to various factors like: the solubility differences of the compounds, the pH and the molality of the medium as well as to the morphofunctional status of the kidney and urinary tract. Between the organic and inorganic compounds some precipitative and/or co-precipitative processes may occur. These processes are at the core of the uroconcrements nucleation due to the appearance of the so called “primers” or “starters” (Garban et al., 1998; Avacovici and Garban, 2007). Metals are present in uroconcrements as an outcome of the fact that they are also present in urine. Berg et al. (1990) found that the urine of the patients with calculosis has higher concentration of Ca and Mg, while the concentrations of Na and K display only minor variations compared to the control group. In the scientific literature there are few systematic studies on the distributions of metals in uroconcrements. Most of these researches are focused on the concentration of metals related with the age and sex of the patient, or with the areal in which they reside (Yamamoto et al., 1987; Hesse et al., 1993; Drăgan et al., 2000; Schubert, 2006). A small number of scientific papers have an in depth approach regarding the qualitative composition of uroconcrements, i.e. the type of urolithiasis and the distribution of metal elements related to the type of urolithiasis (Joost şi Tessadri, 1987; Paluszkiewicz et al., 1990). The FT-IR spectrum reveals two categories of bands: main spectral bands – characteristic for the standard substance and diagnose bands – that are used for the evaluation of components. For uric acid and urates the values are 3015 cm-1, 1305 cm-1, 1220 cm-1, 1120 cm-1, 1025 cm-1, 705 cm-1, 575 cm-1, 475 cm-1 and for phosphates the values are 3420 cm-1, 1470 cm-1, 1430 cm-1, 1055 cm-1, 765 cm-1 (Khand et al., 1991). Using the AAS method, the metal concentrations of the simple and mixed uroconcrements with urates and phosphates were determined and their values have been expressed as μg / g calculi in order to confer a unitary way for evaluation. The results concerning the concentration alkaline and alkaline-earth metals are presented in Tabel 1 for the uroconcrements having urates as dominant component and in Table 2 for uroconcrements having phosphates as dominant component (Drăgan et al., 2000). The obtained values of studied alkaline-earth metals (Ca, Mg) are comparable with those of authors like Bellanato et al. (1987) and Joost and Tessadri (1987). If in the urates lithiasis the dominant metals are Ca and Na in those with phosphates prevail Ca and Mg. This is due to the electrochemical bondings that lead to tricalcic phosphate and ammonium-magnesium phosphates. All these ions take part in the lithogenic process.

73

Mixte

Simple

Mixte

1748.14+586.12

19 8

Oxalate-Urate (O-U)

Oxalate-Urate- Phosphate (O-U-P)

338.75+139.84

9

8

946.51+113.67

191 253.00+88 502.00

187 342.00+52 814.00

121 416.00+47.200.00

X + SD 638.36+281.56

Ca

8

19

9

nu 48

6

Oxalate-Phosphate-Urate (O-P-U)

2241.79 ± 513.53

X + SD

Ca

44

994.41 ± 141.82

44

np

6

74

972.93 ± 68.13

6

44

192 816.80 ± 89601.90

6

938.41 ± 496.83

34530.40 ± 4985.70

5347.51 ± 1844.78

57218.61 ± 2141.93

X + SD

Mg

34350.40 + 4985.70

412.93+ 27.31

376.14+102.19

162 014.23 ± 79167.71 21

194 126,00 ± 29863.20

Mg X + SD 142.61 + 93.09

42 2397.46 ± 1017.84 42 118 967.21 ± 57416.61 42

np

13496,23 ± 3862.49 21 2798.82 ± 987.71 21

5312.79 ± 187.31

9885.78 ± 426.51

X + SD

X + SD

np

K

Na

Note: n- number of cases;⎯X – mean values; SD – standard deviation.

21

44

Oxalate- Phosphate (O-P)

Phosphate-Oxalate(P-O)

42

np

Phosphate (P)

Types of urolithiasis

Concentration of metals (μg/g calculus)

Table 2. Alkaline and alkaline-earth metals metals in uroconcrements having phosphates as dominant component

8

19 491.13+187.02 19

9

nu X + SD nu 48 198.86+101.23 48

K

Note: n- number of cases;⎯X – mean values ; SD – standard deviation.

2251.18+521.16

1319.23+418.51

9

Urate-Oxalate (U-O)

Simple Urate (U)

X + SD 593.16+262.07

Na nu 48

Types of urolithiasis

Concentration of metals (μg/g calculus)

Table 1. Alkaline and alkaline-earth metals in uroconcrements having urates as dominant component

The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

CONCLUSIONS 1. By means of Fourier transformed infrared spectroscopy (FT-IR) there were established the types of urolithiasis. The metallic composition of the simple and mixed uroconcrements having urates and phosphates as dominant components have been determined by means of atomic absorption spectroscopy (AAS). 2. Metallograms of alkaline and alkaline-earth metals concentration in the uroconcrements having urates as dominant component showed a decrease in the series: Simple lithiasis Ca > Na > K > Mg Binary lithiasis Ca > Na > Mg > K Ternary lithiasis Ca > Mg > Na > K 3. Alkaline and alkaline-earth metals concentration in the uroconcrements having phosphates as dominant component decreased in the series: Simple lithiasis Ca > Mg > Na > K Binary lithiasis Ca > Mg > Na > K Ternary lithiasis Ca > Na > K > Mg Note. This paper is dedicated „in memoriam” to Prof. Dr. Petru Drăgan (February2, 1932 – November 12, 200 ) head of the University Clinic of Urology Timişoara, Faculty of Medicine, University of Medicine and Pharmacy “Dr. Victor Babeş” Timişoara (1987-2005)

REFERENCES 1. Avacovici Adina-Elena, Gârban Z. - Metallograms of uroconcrements with purine composition, pp.45-48, in Proceedings of the 14th Symposium on Analytical and Environmental Problems, (Ed. Galbacs Z.) Publ. by SZAB, Szeged, Hungary, 2007. 2. Berg W., Bothor C., Geyer H. - Untersuchungen zur Kristallisationsneigung von Calciumoxalat in Urinen - eine Studie zur experimentellen und rechnerischen Ermittlung der Harnsteinbildungsrisikos, Z. Urol. Nephrol., 1990, 83(7), 347-357. 3. Channa N.A, Ghangro A.B., Somro A.M., Noorani L. – Analysis of kidney stones by FTIR spectroscopy, J. Liaquat. Uni. Med. Health. Sci., 2007, 6 (2), 66-73. 4. Drăgan P., Daranyi Gabriela, Bucuraş V., Avacovici Adina, Vincu Mirela, Gârban Z. Profile of metallograms in phosphatic uroconcrements, pp. 888-895 in "Mengen und Spurenelemente, 19. Arbeitstagung 1999" Fr. Schiller Univ. Jena (Hrsg. Anke M. et al.), Verlag Harald Schubert, Leipzig, 1999. 5. Gârban Z., Daranyi Gabriela, Drăgan P., Avacovici Adina - Metallograms in simple and mixed urolithiasis, J. Trace Elements Experimental Medicine, 1998, 11, 376. 6. Haraguchi H. - Metallomics as integrated biometal science. Journal of Analytical Atomic Spectrometry, 2004, 19, 5–14. 7. Hesse A., Siener R., Heynck H, Jahnen A. - The influence of dietary factors on the risk of urinary stone formation, Scanning Microsc, 1993, 7, 1119-1127. 8. Joost J., Tessadri R. - Trace element investigations in kidney stone patients, Eur.Urol., 1987, 13, 264-270. 9. Khand F.U., Khuhawar M.Y., Memon S., Ansari A.F. – Use of infrared spectroscopy for the identification of urinary tract calculi, Jour. Chem. Soc. Pak., 1991, Vol. 13, no. 1, 1924 10. Paluszkiewicz C., Kwiatek W.M., Galka M. - Trace Elements relations to renal stone phases, Nuclear Instruments and Methods in Physics Research, B-49, 234-237, 1990. 11. Schubert G. – Stone analysis, Urol. Res., 2006, 34, 146-150. 12. Yamamoto I., Itoh M., Tsukada S. - Determination of cadmium, cooper, zinc and lead in human renal calculi in both cadmium polluted and non polluted areas, Bull.Environ.Contam. Toxicol., 1987, 39, 343 349.

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SYNTHESIS AND CHARACTERIZATION OF Co(II) CARBOXYLATES RESULTED IN THE Co(NO3)2 – 1,3-PROPANEDIOL REDOX REACTION Dippong Thomasa, Pauliuc Ivanb , Pacală Adinac a

Water Treatment Company SC Apaserv Satu Mare SA, Gara Ferăstrău Street no 9/A, 440210, Satu Mare, Romania b University of Agricultural Sciences and Veterinary Medicine of Banat Timisoara, Arad Way, no 119, Timisoara c Water Treatment Company - AQUATIM, 11A Gh.Lazar Street, 300081 Timisoara, Romania. E-mail: [email protected]

ABSTRACT This paper presents the study of the redox reaction Co (NO3)2 – 1, 3 propanediol (HOCH2CHCH2OH) and the characterization of its product by means of thermal analysis, FTIR spectrometry and acidic – basic titrations. The study of the acidic – basic properties of the redox reaction product, correlated with the thermal analysis and FTIR spectrometry, highlights the formation of cobalt malonate (1.3 propane dicarboxilic acid). This product that thermally decomposes at 300°C was used as precursor for cobalt oxides. As evidenced by XRD analysis of the annealing products at 400°C and 700°C, nanocrystallites Co3O4 is obtained at both temperatures. INTRODUCTION This method consists of two steps: the preparation of the precursors that contains the metallic ions in the desired molar ratio and the thermal decomposition of the precursors [1]. The method used in the paper for the preparation of cobalt oxides, use as oxide precursor the product of the redox reaction between cobalt nitrate (Co(NO3)2.6H2O) and 1,3 propanediol (1,3PD) [2]. For the characterization of the precursors we can use thermal analysis,IR spectrometry and acidic-basic titrations. Titration techniques have the advantage of ease of implementation, cost-effectiveness and accuracy. Electrometric titrations have also the advantage of automation, increasing the analysis throughput and securing the consistent quality of the results. The study of acidic–basic properties of the precursor allows us to presume if we have a carboxylate compound [3]. The thermal analysis of the obtained precursor showed that it decomposes in the range of 200-300°C, leading to Co3O4 as nanocrystallites. MATERIAL AND METHODS The reagents used in synthesis were: Co (NO3)2.6H2O and 1,3 propanediol (1,3PD), of purity p.a. (Merck).The method of synthesis consists in dissolving the cobalt nitrate in the appropriate amount of 1,3-propanediol, followed by controlled heating at temperatures above 100°C until the onset of redox reaction, visible through the release of nitrogen oxides. The temperature of redox reaction initiation is around 140°C, this is an energic reaction, an important role here is played by the catalytic character of cobalt. Depending on the molar ratio (NO3-:1.3PG) the reaction may be more or less controlled, the reaction product is difficult to isolate (presents a high tendency for combustion). Reaction products were kept at a temperature of 140°C until the end of eliminating the brown gas (reaction completion).Oxidation of 1,3-PG takes place at the dicarboxylic anion, in the system is formed the cobalt malonate. The powder obtained at 140°C was washed with acetone for removing of reactant excess. The obtained products were characterized by thermal analysis, FT-IR spectrometry and conductometric/ pH-metric acidic-basic titrations. In order to obtain

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cobalt oxides, the precursor was thermally decomposed at 300oC and annealed at 400oC and 700oC. The annealing products were studied by XRD. Thermal analysis was performed on a 1500D MOM Budapest Derivatograph. The heating was achieved in static air, until 500oC, with a heating rate of 5°C/min, on Pt plates using α-Al2O3 as inert material. The FT-IR spectra were registered on a Schimadzu Prestige-21 FT-IR spectrometer, in KBr pellets, in the range 4000-400oC. Phase analysis was achieved with a Bruker Advanced diffract meter (the samples obtained at 400°C) using Cu-Kα radiation (λCu= 1, 54056 Ǻ) The acidic-basic properties of the precursors were studied by conductometric/ pHmetric acid-basic titrations, on a Crison MM41 Multimeter. RESULTS The redox reactions between cobalt nitrate and 1,3 propanediol lead to formation of coordination compounds of Co(II) with the carboxylate anions, diols oxidation products [4]. These compounds can be used as precursors for the corresponding cobalt oxides [5].

The reaction is promoted by the formation of the coordination compounds between the resulted carboxylate ions and the Co (II) cations (the diol does not interact with HNO3). Samples were prepared which corresponds to the reactions with molar ratio NO3-: diol stoichiometric = 1: 0.375 (G1) and the excess diol NO3-: 1.3 pg = 1:0,75 (G2). The redox reaction Co (NO3)2 – 1, 3 PG was studied by thermal analysis. For this purpose the solution of cobalt nitrate in 1, 3 propanediol was deposed in thin film on Pt plates and heated in air, until 500°C. Figure 1 presents the obtained TG and DTA curves. The presented thermal curves show two exothermic processes. The first process that takes place in the temperature range 150-180oC, corresponds to the redox reaction Co (NO3)2 – 1, 3 PG (visually confirmed by the formation of the brown gas-nitrogen oxides). As a result, coordination compounds form between Co (II) and the diol oxidation product. The second exothermic process in the range 250-300oC, can by assigned to the oxidative decomposition of the formed complex [5]. Taking into account the results of thermal analysis, we have choose the value of 140°C for the synthesis of the carboxylate –Co(II) compounds, used as precursors for the Fig 1. Thermal curves of the sol. Co (NO3)2-1,3PG cobalt oxides. G1 spectrum (corresponding to the sample synthesized at the stoichiometric reports), from Figure 2 shows characteristic bands of carboxylate anions coordinate to metal ions: νas (COO-) at 1646 cm-1, νs(OCO) at 1360 cm-1, and νs(CO ) + δ (OCO) at ~ 1310 cm-1, confirming the formation of this type of compound. The bands at 2974 cm-1 , 2940 cm-1 and 2870 cm-1 are characteristic to the stretching vibrations of the C-H bonds from-CH3 [6,7].

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G2 spectrum (corresponding to the sample synthesized with diol excess) present in addition to bands characteristic of cobalt carboxylate, the characteristic bands of excess diols: bands at 3000-2800 cm-1 are characteristic C-H bonds from–CH3 şi –CH2groups, bands at 1200-900 cm-1 are characteristic ≡COH groups. Figure 3 shows the thermal behavior of compound G2 which is approximately similar. The thermal analysis of the precursor (fig.3) has evidenced Fig 2. FTIR spectrum of the G1 and G2 precursors obtained at 140oC that the thermal decomposition takes place in the range of 250-300oC with a pronounced exothermic effect, corresponds to oxidative decomposition of complex combinations formed (Malonic). Decomposition occurs with the generation in situu of a reducing atmosphere which leads to the reduction of Co (II) until Co metal, with its reoxidation to a poorly crystallized oxide, with increased reactivity. The residue at 400oC is, according to the XRD is the Co3O4. Taking into account the mass of the residue at 400oC we have thus calculated the content of Co in the precursor, of 29% (wt). Up to 500 Fig. 3. Thermal behaviour of the G2 o C, the mass remains constant [8,9]. precursor synthesized at 140°C In order to establish if the precursor Co (II) hydroxylactate, we have studied the acidic-basic properties, by using conductometric and pHmetric titrations. In this purpose a corresponding mass of precursor that contains 2.10-4 moles of Co (II) was solved in 10 cm3 of 0.1 mol/l HCl solution. The solution was then titrated with 0.1 mol/L NaOH solution. The processes that may take place when the precursor is treated with HCl solution and with NaOH solution are presented in scheme 1. 2-

C 3H2O4

C 3H3O4 CoOH

+

Consumul

+ + +

2 H +

Ha

+

Ha

+

H

+

Consum OH C 3H4O4 C 3H4O4

Co

2+

+

H 2O

+ 2 OH + C oOH + OH Co

2+

-

-

C o( O H) 2 C o ( O H) 2

Scheme 1. The processes that take place when the precursor is treated with HCl (left) and with

The quantity of consumed acid was calculated from the difference between the quantity of HCl introduced and the quantity of unreacted HCl (corresponding to the first equivalence point). The quantity of NaOH consumed was evaluated from the difference between the quantity of NaOH corresponding to the second equivalence point and the amount of introduced HCl and the amount of unreacted HCl (corresponding to the first equivalence point). The precursor is a Co (II) malonate (CoC3H2O4), when the quantity of consumed HCl (for protonation of malonate ion) is equal with the quantity of consumed NaOH (for precipitation Co(II) as Co(OH)2). The results obtained from the conductometric and pHmetric titrations are presented in table 1. Table 1 The results from the titrimetric analysis

Experimental molar ratio H+/OHNr Conductometric pH-metric G1 4.0± 0.2 4,2 ± 0.3 G2 4.0 ± 0.2 4,0 ± 0.3

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Compound n(CoOH)2 .CoC3H2O4

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In the Figures 4 and 5 are presented the curves of conductometric titration and pH-metric of acid solutions G1 and G2 samples (1.3 PG) and of the HCl solution (volume of solution used to dissolve the precursor and processing experimental results. (a)

(b)

(a)

(b)

(c)

(c) (d)

(d)

Fig 4. Conductometric titration curve (a), pH metric (b), calculation of the average equivalence volume (c), calculation of the reaction ratio (d) for the sample G1

Fig 5 Conductometric titration curve (a), pH metric (b), calculation of the average equivalence volume (c), calculation of the reaction ratio (d) for the sample G2

The precursor was thermally decomposed at 300°C for 6 hours and then annealed for 3 hours at 400°C and at 700°C. At the thermal decomposition of carboxylates type combinations, it is generated in situ a reducing atmosphere (C, CO) depending on the nature of the hypothetic complex combination. Reducing atmosphere may be influenced by the nature and diol excess which can be found next to the synthesized compounds, as well as by the means (conditions) in which the decomposition is performed (heat treatment), it was studied the way by which it can be obtained as unique crystalline phase Co3O4 and CoO respectively. The annealing products were studied by XRD analysis (fig.6). According to XRD data the only crystalline phase obtained at both temperatures was of samples G1(1), Co3O4. The presence of CoO in the spectrum (1) may be Fig 6. RX spectra G2(2) at 400oC, G1(3),G2(4) at 700oC due to the nature of the precursor synthesized. Figure 7 presents the FT-IR spectra of the samples G1 and G2, calcinated at 400°C. It is notable characteristic bands of the Co3O4 Co-O bonds (660 cm-1 and 570 cm-1), confirming results obtained by RX diffraction analysis. The same samples G1 and G2 were calcinated at 700°C for 2 hours, when all RX spectra were recorded as single phase well crystallized Co3O4 (Fig. 6). The corresponding FTIR spectra presents the same characteristic bands of Co3O4 Co-O bonds (660 cm-1 and 570 cm-1) (Fig. 7). From the XRD data we have estimated the average diameter of the Co3O4 crystallites, using Scherrer formula. It resulted that Co3O4 is 7. FT-IR spectra of samples G1 (1), G2 obtained as nanocrystallites with diameters of ~ 20 nm Fig(2) at 400oC, G1 (3), G2 (4) at 700oC at 400°C and ~30 nm at 700°C.

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CONCLUSIONS ¾ It was studied the formation of some carboxylate type complexes of Co (II) by redox reaction of Co(NO3)2 and diol, depending on the molar mixing ratio of them; ¾ The products obtained from the redox reaction were characterized by thermal analysis, FT-IR spectrometry and acid-base titrations (conductometric and pH-metric); ¾ Through thermal analysis and FT-IR spectroscopy was established the optimal synthesis temperature (140°C) of the products obtained from the redox reaction; ¾ In the given conditions, based on the results of thermal analysis, FT-IR spectrometry and acid-base titrations in the Co(NO3)2: diol system, was confirmed that the resulting products are carboxylate type; ¾ All techniques have evidenced the formation of coordination compounds of Co(II) with the malonate anions, resulted by 1,3 PG oxidation. ¾ According to the study of acidic –basic properties of the product, we have probably obtained a mixture of Co(II) malonate and Co(II) hydroxyl malonate. ¾ It was shown that regardless of the nature of the precursor, decomposition occurs up to ≈ 300oC, with the generation of a reducing atmosphere, depending on its nature; ¾ It was found that during thermal decomposition of precursors, reducing atmosphere can lead to partial reduction of Co (II) to Co metallic; ¾ It was set the temperatures of heat treatment and nature of precursors leading to the CoO that Co3O4 unique crystalline phase. ¾ By thermal treatment of this product at 400°C and 700°C we have obtained nanocrystallites of Co3O4 having a dimension of 20nm at 400°C and 30 nm at 700 °C. LIST OF REFERENCE [1] Brezeanu M., Tatu E., Bocai S., Brezeanu O., Segal E.,Patron L., Thermochim. Acta, 78 (1994) 351 [2] Brezeanu M., Patron L.,Cvisturean E., Carp O., Antoniu A., Andruh M., Rev Roum. Chim., 38 (1993) 1291 [3] Dippong T., Stoia M., Stefanescu M., Procceding of XIVth, Symposium on Analitycal and Environmental Problems, 24 sept. 2007, Szeged, Hungary, pp 134-138 [4] Niculescu M., Vaszilcsin N., Bîrzescu M., Budrugeac P., Segal E., Journal of Thermal Analysis and Calorimetry, 65 (2001) p 881-889 [5] Stefanescu M., Dippong T., Stoia M., Stefanescu O., Journal of Thermal Analisys and Calorimetry, 94 (2008), 2 [6] Vencat Narayan R., Kanniah V., Dhathathreyan A., J. Chem. Sci., 118, 2 (2006) 179–184 [7] R. Prasad, Sulaxna and A. Kumar, J. Therm. Anal.Cal., 81 (2005) 441-450 [8] M. Ştefănescu, V. Sasca, M. Bîrzescu, J. Therm. Anal. Calorim, 56 (1999) 579 [9] T. Dippong, M. Stoia, P. Barvinschi, M. Stefanescu, Procceding of XVth, Symposium on Analitycal and Environmental Problems, 22 sept. 2008, Szeged, Hungary, p 229-232

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SAMPLE PRETREATMENT AND ANALYITICAL METHOD DEVELOPMENT FOR DETECTING STROBILURIN PESTICIDES IN AQUEOUS MATRICES János Farkas1, Karyn Le Menach2, Patrick Mazellier2, Hélène Budzinski2, Tünde Alapi3, Krisztina Gajda-Schrantz3, András Dombi1 1

University of Szeged, Institute of Material Sciences and Engineering, H-6720 Szeged, Tisza L. krt.103, Hungary, tel.: +36-62-544-334, e-mail: [email protected] 2 Université de Bordeaux1, Environnements et Paléoenvironnements Océaniques et Continentaux, Laboratoire de Physico-Toxicochimie, UMR 5805 CNRS, 33405 TALENCE cedex, Cours de la Libération 351, Batiment A12, France, tel.: +33 05 40 00 62 82, e-mail: [email protected] 3 University of Szeged, Department of Inorganic and Analytical Chemistry, H- 6720 Szeged, Dóm tér 7. Hungary, tel.: +36-62-544-334, e-mail: [email protected]

ABSTRACT In this study a method development is presented focusing on the measurement of strobilurin pesticides with GC-MS/MS after a Solid Phase Extraction (SPE) preconcentration step. The analysed pesticides were azoxystrobin, dimoxystrobin, famoxadone, fenamidone, fluoxastrobin, kresoxim-methyl, E-metominostrobin, orysastrobin, picoxystrobin, pyraclostrobin and trifloxystrobin. GC parameter optimization, MS Full Scan, Daughter mode and finally Multiple Reaction Monitoring (MRM) analysis had been done to have perfect separation and characteristic transitions. Calibration curves, repeatability and recovery values were determined to describe reliability of the method. During the SPE method development spiked bottled drinking water was used. Four types of cartridges were tested. STRATA-X had been chosen for further analysis with different elution solvents and with different volumes. PDMS/DVB 65 μm SPME fiber had also been chosen amongst three fibers. Parameter optimization such as extraction and desorption time, pH and NaCl dependence were done. Linearity and repeatability tests were carried out. INTRODUCTION The strobilurin pesticides are a quite new group of pesticides. Their development was provided by discovering a natural fungicide (beta–methoxy-acrylic acid). The first commercially available products containing strobilurins were sold in 1996. Their active substances were azoxystrobin and kresoxim-methyl. Until 1999 the amount of sold strobilurin was 10% of all the sold pesticides so it is not surprising that, higher and higher attention is paid to their environmental effects. Further developments and researches resulted in the invention of new strobilurins, such as: azoxystrobin, dimoxystrobin, famoxadone, fenamidone, fluoxastrobin, kresoxim-methyl, metomonistrobin, orysastrobin, picoxystrobin, pyraclostrobin, and trifloxystrobin. They block the mitochondrial respiration by connecting to the so-called Qo place of cytochrome-b, which is a part of the cytochrome-bc1 complex in the membrane of mushrooms and other eukaryotes. While there are only a few publications about their analysis in aqueous solutions, they have been detected in other matrices. The aim of this work was the development of pre-treatment methods (SPE (solid phase extraction) and a SPME (solid phase micro extraction)) and GC (gas chromatographic) parameter optimization for the quantification and qualification of samples containing all the listed strobilurins. [1] [2]

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MATERIALS and METHODS The GC parameter optimization was done on Agilent 5973 GC coupled with Waters Quattro Micro GC Micromass MS. HP-5MS capillary column was used for the separation. Helium was used as carrier gas. The injections were performed in splitless mode using constant gas flow. The optimized GC parameters is presented in Table 1. The ionization energy in the collision cell ranged between 5-50 eV in 5 eV steps. Each molecule provided a characteristic retention time and two transitions for identifying them at certain collision energy. These parameters were transferred to an Agilent 7890A GC coupled with a 7000A MS QQQ detector because better LOD values were available with this equipment. The SPME method development was carried out on this equipment. Table 1. Optimized GC oven parameters Time at initial temperature: 2min Time Rate Temp 2 min 20 °C/min 150 °C 5 min 10 °C/min 320 °C Table 2. Optimum of the transitions and collision energies for MRM mode analysis RT (min)

Compound

Transition 1 (quantification)

16.96 17.15 17.48 18.69 19.6 19.89 20.10 21.11 24.21 24.21 25.54

Picoxystrobin E-Metominostrobin Kresoxim-methyl Trifloxystrobin Dimoxystrobin Fenamidone Orysastrobin Pyraclostrobin Famoxadone Azoxystrobin Fluoxastrobin

145->115 195->167 206->116 172->145 116->89 268->180 116->89 132->104 330->196 344->329 188->144

collision energy 1 (eV) 10 15 5 15 15 15 15 10 20 13 10

Transition 2 (confirmation) 190->147 167->139 131->116 187->172 205->116 238->103 205->116 164->132 197->141 344->156 306->150

collision energy 2 (eV) 15 15 15 10 5 20 5 8 10 18 15

During SPE development three sorbents were tested. These were Oasis-HLB, STRATA-X Reversed phase; Varian Bond Elut HF-PSA and Supelclean LC-NH2. STRATAX cartridge had been chosen as SPE sorbent because it was the most efficient one to extract simultaneously all these pesticides. For optimization of this method, different solvents and volumes were tested and the recoveries, calculated by external calibration curves were compared to each other. Finally 3 ml methanol : ethyl acetate mixture (volume ratio: 1:1) was used to elute the adsorbed compounds. The changing of the solvent to isooctane was performed before injection. PDMS/DVB 65 μm had been chosen as SPME fiber from the other three tested fibers, which were PDMS 100 μm and PA 85 μm. The optimized parameters were: pH=3, next to 5 m/m % NaCl with 60 minutes extraction time and 5 minutes desorption time. 32g 5 m/m % NaCl containing aqueous solution at pH=3 was spiked with 40 μl pesticide containing

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solution, then it was homogenized with VORTEX shaker and finally with ultrasonic bath for 10 minutes. 8,3±0,01g spiked sample were taken into the SPME vials. RESULTS SPE development - Waters MSMS Only STRATA-X cartridge was suitable for all the compounds amongst the four tested cartridges so it was applied in further experiments. The provided recovery values of modified solvent for elution (mix of ethyl acetate and methanol) is presented at table 3 by using external calibration. Table 3. SPE recoveries provided by Waters GC-MSMS Compound

Average recovery (%)

Azoxystrobin Dimoxystrobin Famoxadone Fenamidone Fluoxastrobin Kresoxim-methyl Metominostrobin Picoxystrobin Trifloxystrobin

119,37 90,07 104,10 94,47 155,27 96,92 83,61 104,88 96,94

SPE development - Agilent MSMS Because of the the better LOD values determined with thee Agilent 7890A GC, lower initial concentration in spiked drinking water was possible to be tested. In that case not common initial concentration was used but specified levels based on the LOD values. Three levels were tested: at the LOD level, 2,5 and 5 times higher of this level. Near to the LOD level, the results were absolutely incorrect so here only the other two cases are presented. At table x the acquired recoveries, calculated by external calibration can be seen at two pH levels. Slight improvement can be observed at pH 3 thus it was used after. SPME development Amongst the tested SPME fibers, PDMS 100 had been eliminated because for Metominostrobin it is not appropriate contrary to the other two fibers. At PDMS/DVB the best results were obtained at pH=3, next to 5 m/m % NaCl with 60 minutes extraction time and 5 minutes desorption time. At PA fiber the best results were obtained at pH=7 next to 5 m/m % NaCl with 60 minutes extraction time and 5 minutes desorption time. After comparing these two cases, the PDMS/DVB fiber was selected because it was more efficient in exception of Fenamidone and Pyraclostrobin. Because of the RSD values were not acceptable, when salt was added to the samples, measurement was carried out without salt addition, but still at pH=3. This comparison can be seen below at table 4. As it is clear, the average RSD is better without salt addition, what causes better linearity coefficient for the half of the compounds (grey shading).

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Table 4. LOD, RSD and R2 values with and without salt addition during SPME injections Compound

LOD (ng/l)

RSD % with salt addition

RSD without salt addition %

Azoxystrobin Dimoxystrobin Kresoxim methyl Famoxadone Fenamidone Fluoxastrobin Metominostrobin Picoxystrobin Pyraclostrobin Trifloxystrobin

25 2 15 100 100 100 25 15 25 25

3,92-39,97 9,57-27,56 10,11-29,78 0,96-24,71 11,03-62,04 8,46-50,51 4,21-56,57 8,25-33,09 2,27-52,68 6,41-38,55

4,29-37,6 5,9-26,66 4,70-34,95 2,07-34,14 0,58-40,82 2,53-19,2 11,76-37,05 10,69-20,56 7,79-45,3 0,61-28,65

R2 with salt addition 0,973 0,9714 0,9751 0,99 0,9931 0,9867 0,9256 0,9934 0,993 0,9928

R2 without salt addition 0,9941 0,9859 0,994 0,9925 0,9925 0,9828 0,9283 0,9751 0,9904 0,9819

CONCLUSIONS • Solid phase extraction method had been developed and refined to have maximal recovery values for STRATA-X reversed phase sorbent. Several concentration levels were tested. • Solid phase microextraction method had also been developed for PDMS/DVB fiber for direct analysis from water samples. • Gas chromatographic method had been developed to separate and detect strobilurin pesticides in organic solvent. Characteristic transitions coupled with certain collision energies are also represented in this work for each compound. ACKNOWLEDGEMENTS The authors express their gratitude to the NKFP DA_THERM TECH_08_A4 project and the European Regional Development Fund (TÁMOP-4.2.1/B-09/1/KONV-2010-0005). This document has been produced with the financial assistance of the European Union (Project HU-SRB/0901/121/116 OCEEFPTRWR Optimization of Cost Effective and Environmentally Friendly Procedures for Treatment of Regional Water Resources). The contents of this document are the sole responsibility of the University of Szeged and can under no circumstances be regarded as reflecting the position of the European Union and/or the Managing Authority. LIST OF REFERENCES [1] Navalón A., Prieto A. Araujo L., Vílchez J. L, (2004). Determination of pyrimethanil and kresoxim-methyl in soils by headspace solid-phase microextraction and gas chromatography-mass spectrometry, Analytical and Bioanalytical Chemistry, 379, p. 1100-1105. [2] Bartlett DW., Clough JM., Godwin JR., Hall AA., Hamer M., Parr-Dobrzanski B., (2002). The strobilurin fungicides, Pesticide Management Science, 58, p. 649-662.

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ENVIRONMENTAL AND ECONOMIC ASPECTS OF BROWNFIELD REVITALISATION1 Roncz Judit, Klara Szita Tóthné University of Miskolc, Institute of World and Regional Economics e-mail: [email protected]; [email protected] ABSTRACT This study presents some general aspects of brownfields from definition to assessment methods. There are several approaches to define brownfield, but there is a common agreement among researchers on its typology. The economic and environmental aspects as evaluating methods depend on the varying revitalisation goals. But our goal is to analyse the different tools in order to find the best method for evaluation of environmental and sustainability state of the sub region and settlements in the North Hungary region. Among the available numerous tools SWOT analysis, Cost Benefit Analysis (CBA), utility based evaluation, indicator based sustainability assessment can be mentioned as most significant. In this paper we introduce the major evaluating processes and the risks of brownfield revitalisation, the rehabilitation possibilities and remediation. INTRODUCTION The problem solution of brownfield requires an interdisciplinary approach. It needs the harmonised approach of the natural science, social and economic aspects. The major related science fields are: geography (social and economic geography), space informatics, urbanism, regional development, environmental protection, regional science and statistics.2 The revitalisation of brownfield started in the European Union in the last decade. The sustainable urban development program (1998) focused to develop of brownfield area rather than greenfield development. The Urban II program has the target to regenerate cities and neighbourhoods, in which the brownfield have also priority. As mixed-purpose development, the restoration of buildings and public spaces, cleaning of derelict and contaminated natural environmental sites, conservation of historic and cultural heritage and sustainable job creation forms the field of the regeneration tools. CLARINET3 network has established a workgroup for brownfield revitalisation. The workgroup’s most important goal is to make a contact between soil pollution and urban development (Barta, 2003). Recently in Hungary the issue of brownfield rehabilitation has become a key factor in designing urban territorial development in the practice and as research.

1

Supported by TÁMOP-4.2.1.B-10/2/KONV-2010-0001 project Czira, T. –Kukely, Gy.: Az átalakuló iparú térségek környezeti konfliktusainak fenntarthatósági értékelése Északkelet-Magyarországon Környezetállapot értékelés Program Pályázati tanulmányok 2003-2004 KÉP http://www.terport.hu/webfm_send/302 3 „Contaminated Land Rehabilitation Network Technologies” 2

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THE TERM OF BROWNFIED There are a number of alternative definitions of “brownfield” land while the categorisation has a common feature. In general the term "brownfield site" means real property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant. It is a piece of industrial or commercial property that is abandoned or underused and often environmentally contaminated, especially one considered as a potential site for redevelopment (US EPA). Another definition: ’brownfield land is a land in a town or city where houses or factories have been built in the past, but which is not being used at the present time Barta (2003). Barta (2003) also states that the Hungarian situation differs from USA or Western European brownfield situations, although the categorisation of the brownfield is the same: industrial, mining site, railway field site, military or other. The reason of this differentiation is the characteristics of Hungarian industrial development, where the heavy industry and big manufacture was dominant. The revitalisation means reutilisation of mainly urban fields and differs from the term rehabilitation in the way that the later activity refers to the returning of the brownfield’s original function. Both of the term involves remediation activities. The Nicole project determines the different types of brownfield sites, that mainly use the risk based definitions of contaminated land. As it follows: previously developed land, historical urban green space, subject to legal sanction, land affected by contamination, derelict, under used and vacant. Similar to the above mentioned, COBRAMAN project categorised the following brownfield sites: industrial site; mining site; military site; railway land site; waterfront site; former city services site; other site. But in all kinds of brownfield type the contamination of the environmental elements can play a significant role in its future utilisation: the pollution is blocking the economical development and reutilisation of the real estate. Soil contamination is especially pronounced negative considerations, also like unsettled ownership, the general speculation on the plots and buildings, low real estate prices due to the lack of reutilisation demand. As addition to the problems, the polluter is not responsible for the cause, but - after discovering the problem the new owner is responsible for remediation. All these reasons are kept away potential investors from the brownfield areas, and they choose better, safer, green-field sites. (Czira, Kukely, 2004) METHODS As methodological tool we used meta-analysis. We reviewed scientific papers about brownfield, beside this the legislation background and revitalization projects were analyzed. We examined the methods used in economic and environmental evaluation of brownfields. This serves as starting point of our research in which our goal is to find the best adaptable methods for brownfield evaluation in the North Hungarian Region. THE STATE OF THE BROWNFIELD Problem solution of brownfield occurred firstly in developed countries like in the USA, England, France, and Germany, where the former heavy industrial area was left abandoned after the structural changes and demand came up for their rehabilitation (by the society). In USA the Brownfields Economic Development Initiative (BEDI) is a key competitive grant program that promote economic and community development. The main goal is the redevelopment of abandoned, idled and underused industrial and commercial facilities where expansion and redevelopment is burdened by real or potential environmental contamination.

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BEDI funds are primarily targeted for use with a particular emphasis upon the redevelopment of brownfields’ sites in economic development projects and the increase of economic opportunities for low-and moderate-income persons as part of the creation or retention of businesses, jobs and increases in the local tax base. The Brownfields Program creates many benefits for local communities in USA.4 Turning brownfield land into a successful green space is a central issue of European research program too. In Central Europe the COBRAMAN project is collecting and systemizing the knowledge of the revitalization projects5. This contains about 62 characteristic data of brownfield areas (localisation, area, present usage, owner, infrastructure, contamination etc.) connecting also to 42 Central European project in Czech Republic, Germany, Italy, Poland, Slovenia. The brownfield project of the Centre for Environmental Studies was launched in 2004 in order to conduct a survey of Hungarian brownfield sites, collecting good and bad practices as well as foster exchange of experience related to their utilization. As the result of the survey in Hungary 183 brownfield site was located in 66 townships. In Hungary, approximately 12 thousand hectare brownfields are registered, what means 15.000 contaminated sites that are stored in a GIS information system called KÁRINFO. In North Hungarian Region the area of brownfield site is 1.414.761 m2, and the economic value is at about 1561,2 million HUF.6. Another research has detected - in 2007 – 2.579 ha in the North Hungarian Region, which are divided to industrial area (46%), mining (5)%, military (8)%, and other (41%) types of brownfield site. From the 2.579 ha 13% related to former steel production. (Madarász, 2007) REVITALISATION OF BROWNFIELD Utilization of brownfields can play a key tool to prepare certain areas for new usage, to enable the growth of a region and to reduce regional differences. It serves as long-term development strategy. Taking out greenfield areas – from further industrial investments - contributes to the support of sustainable development. Many brownfield owners are unfortunately satisfied with leaving their properties in their current condition. In some cases the neighbourhood property owners may not support of the rehabilitation in brownfield sites, although the level of contamination is so slight that it seems unlikely to harm anyone – said the Brownfield Centre in USA. When we want to evaluate the economic and environmental aspect of revitalisation firstly we need to review the goals of redevelopment options. Schädler et al. (2011) have collected these: • alternative clean-up goals, • alternative site use options, • the social, economic, and ecological sustainability of land use alternatives, • all of the economic implications, including clean-up costs, liability, and site use benefits, • uncertainties, • feasible and accessible to stakeholders, and, • generate results that are understandable to stakeholders (not only to experts in the respective fields).

4

http://portal.hud.gov/hudportal/HUD?src=/program_offices/comm_planning/BEDI http://database.cobraman-ce.eu/ 6 Brownfield sites in the Northern Hungary The database was prepared by the Centre for Environmental Studies, 2004. 5

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ASSESSMENT OF REVITALIZATION There different kind of methods is for the evaluation of the brownfield revitalisation. • SWOT (Data requirements) • Conflict analysis • Estimation of costs for site preparation o Groundwater remediation costs o Soil remediation costs, o Building deconstruction cost • Market value estimation and mercantile value reduction (MVR) • Sustainability assessment (Schädler et al. /2011) Evaluating on base of SWOT Schug and Ertel (2010) investigated different aspects, as well as micro and macro site, stakeholder interest, planning, key position within city department, situation of contamination, own identity of Feuerbach, good connection/accesability, station forecourt as space with potential, greenbelt, culture, politics, administration, investors and users, neighbours and inhabitants in the area, and they adapted these for pilot projects. The conflict analysis The conflict analysis is a procedure which identifies those regions on the site that will require remediation given the information on the distribution of contaminants, as well as on the map of compliance criteria attributed to each specific redevelopment option. Estimating of cost clean up • The type of cleanup required at a brownfield site depends on a number of factors. These factors include location, type and amount of contamination present, how widespread and deep the contamination is and the intended future use. • The most common types of cleanups include removal or treatment of contaminated soil, capping and/or covering the contaminated area, and cleaning up ground water.7 Doick et al (2009) reviewed evaluations of brownfield greening projects. While definitions of a successful greening project vary, the focus tends to be economic, despite the difficulty in quantifying the financial benefits. The concept of ‘success’ tends depends on the funded or developer’s needs, and under represents other stakeholders. For example, the social and economic wellbeing of the surrounding communities are often not considered. They suggested more focus on outcomes by the logic model, and a flexible monitoring process which involves a broad range of stakeholders. Economic and environmental utility based evaluation Madarász (2005) proposed an evaluating method on the basis of the risk and he developed a qualitative evaluation matrix of remediation actions and five criteria that the remediation goal value has to comply with: o human health risk protection; o environmental media status conservation; o ecological risks aspect; o financial feasibility; o technical feasibility.

7

http://www.epa.ohio.gov/portals/30/SABR/docs/Ohio%20Brownfield%20Toolbox.pdf, page 18

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Estimated remediation costs contents: • Groundwater remediation costs, • Soil remediation costs, • Building deconstruction costs, • Market value estimation and mercantile value reduction (MVR), • Sustainability assessment. Evaluating based on indicators Wedding and Crawford-Brown (2007) proposed 40 indicators in four categories to evaluate the sustainability and they applied weightings method too to determine the sustainable frame of redevelopment of brownfield. CONCLUSION The benefits of brownfield redevelopment are moving on a large scale. The benefits for community can be the eliminated health and safety hazards; eliminated eyesore sites. The revitalisation results in new investments with new job creation, increase in the productivity of land and property values and tax receipts for local and state governments. During our research we found varying definitions of brownfield, a lot of evaluating and assessment methods and pilot projects serving as good starting point to find the best of evaluating methods for our region. Among these as best the ‘estimated remediation costs content method’ seems to be suitable for our region combining with the utility based practise. REFERENCES: Schug, B.; Ertel, T. (2010): Brownfield SWOT WP No. 4 Output No. 4.2.1, COBRAMAN project Czira, T., Kukely, Gy. (2004): Környezetállapot értékelés Program Pályázati tanulmányok 2003-2004 KÉP http://www.terport.hu/webfm_send/302 Doick, K.J.; Sellers, G.; Caston-Broto, V.; Silverthorne, T. (2009): Understanding success in the context of brownfield greening projects: The requirement for outcome evaluation in urban greenspace success assessment. Urban Forestry & Urban Greening. 8:163-178. Madarász, T. (2005): Kockázatfelmérés alkalmazása és kritériumrendszere szennyezett területek kármentesítése során, Doktori értekezés, Miskolci Egyetem Madarász, T.; Ádám, L.; Mikita, V.; Mészáros, A. (2007): Brownfield redevelopment status and lesson from Northern Hungary, NICOLE project 2007. http://www.nicole.org/publications/Akersloot/Madarasz_T_CaseHu.pdf S. Schädler, M. Morio, S. Bartke, R. Rohr-Zänker, M. Finkel (2011): Designing sustainable and economically attractive brownfield revitalization options using an integrated assessment modelJournal of Environmental Management 92 (2011) 827e837 The estimated Brownfield sites in Europe COBRAMAN project, 2008-2011 http://www.cobraman-ce.eu) Wedding, G. Christopher; Crawford-Brown D. (2007): Measuring site-level success in brownfield redevelopments: A focus on sustainability and green building Journal of Environmental Management, Volume 85, Issue 2, October 2007, Pages 483-495

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SUSTAINABLE DEVELOPMENT AND DILEMMAS IN SUSTAINABILITY MEASUREMENT1 Roncz Judit, Klara Szita Tóthné University of Miskolc, Institute of World and Regional Economics e-mail: [email protected]; [email protected] ABSTRACT The Regional LCA Competence Laboratory – established in the Institute of World and Regional Economics - is recently working at the elaboration of a demonstrative project which can serve the ambitious goal to find the way to develop a methodology for measuring regional sustainable development on LCA basis. As new approach, we make efforts to fulfil the requirements of broader sustainable development concept, somehow combining it with the product-specific, plant-level modelling techniques of LCA analysis. Both of the new approach elements are challenging, during the elaboration we had to face with severe problems. In this paper we gather the most relevant dilemmas of sustainable development measurement. After briefly summarising the current trends in SD measurement we define the problematic factors which have not been yet solved, and create the general dilemmas of SD measurement. INTRODUCTION Our research aim is to develop a new methodology that can combine the advantage of a life cycle and input-output analysis to evaluate environmental, social and economic performance at regional level. The novelty of the research on the one hand is that only the U.S. had such research programs, in Europe similar, complex economic, social and environmental LCA approach has not yet been made. On the other hand this research can serve as an impetus for the domestic LCA research that is only in their infancy. The Laboratory aims within this project: to develop a new methodology, which can give a reliable evaluation for the regional environmental performance; to assess the sustainability of the region and to support strategic decision-making with developing optimalisation scenarios for the region. So high value added can be realized on both the methodological (development of research potential) and practical application side (contribution to decision making). Our research has the following steps:

Figure 1: Research process Source: Own compilation 1

This paper is supported by NKTH Baross Gábor Program: LCANORRINO „Development of NORRIA North Hungarian Regional Innovation Agency LCA based environmental regional performance evaluation and optimalisation service, NHR - LCA –NORRIA. REG_EM_KOMP_09, 2009

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As a starting point we analyzed the current available methods of SD measurement and selected those LCA methods that can be suitable for a broader concept sustainable development measurement. The harmonization of the two levels – the macro, top-down approach of SD measurement, and micro, plant level LCA – is not easy to achieve. We have to solve the problem of data requirements, appropriate evaluation criteria, consideration of the risks of the assessment, the level of simplification and therefore possible the distortion of the results. Here in this paper we summarize all difficulties and considerations, which we have to face with. Those factors which raise questions not only when we combine the above two direction in SD measurement, but in case of a simple, one-way SD approach too. ABOUT SUSTAINABE DEVELOPMENT AND LCA The concept of sustainable development and the recognition of the interdependence between the economic system and the environment got in the centre of interest during the 1970s by Meadows and her collaborators (Meadows, 1972). According to the idea asserted by them continuous economic growth will result in serious deterioration of environment unavoidably, which, in turn, may cause global scale collapse of societies eventually (Pezzey, 1992). Finally, this thought ended up in recognition that economic development can be sustained without limits but only in such a case when developing process is modified to take into consideration the dependence on natural environment. Unsustainability of economic growth got more attention when Brundtland published its Report in 1983 (WCED (1987). So, the concept of sustainability has been present long ago, but its sense is unclear: diversified and even conflicting meanings attach to the concept. Hediger (2004) states that sustainable development is much more than sustainability of natural environment. So, such an approach can be qualified as a more complex interpretation of sustainability that meets the requirements of environmental, economic and social sustainability. All three aspects of this newer, complex approach are needed to judge the sustainability of a given development process (Goodland, 1995; van den Bergh, 1997). However, overstressing any of these pillars may end in a onesided attitude. So, sustainability of development cannot be judged merely on the basis of the sustainability of the natural environment, in the same way as an economically sustainable economic process is not necessarily sustainable environmentally on long term. The independency of the points of view can ensure the possibility of a careful judgement. Moreover, complex indices, such as HDI, applied generally, cannot correct the shortages of one-pillar models, since they assume some substitutability among the components they measure. The importance of environmental protection is becoming increasingly prominent in all spheres of human society while more and more environmental impact analysis method tried to give a reliable and coherent estimation (Fullana et. al, 2009). Among others life-cycle assessment (LCA) became a widely used tool in the last decade to estimate environmental effects of the entire life cycle of products and services. The Life Cycle Assessment (LCA) is a comparatively recent tool that has rapidly grown to become a standard procedure for environmental scientist and engineers alike to investigate and asses the environmental performance of a wide range of human dominated processes. As the concept of three-pillar sustainable development became widely accepted the LCA approach has been also widened with these new aspects. The goal is to get a more consequent picture and evaluation from ongoing human and natural activities. As LCA models typically use product-specific, plantlevel data one of the biggest challenges among LCA researchers is to develop new model based upon general macro or regional (meso) level economic datasets. The aim is to indicate

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regional economic and environmental effects from the production of goods and services and to support the regional policy makers.

MEASURING REGIONAL SUSTAINABLE DEVELOPMENT According to our literature review we grouped the current SD measuring methods into three groups. All of it has some characteristic feature. 1) Econometric modelling of SUS development The econometric models, although often appear as a model of sustainable development, but mostly seeks to forecast only the positional evolution of economic growth. Examples can me mentioned here like PANTA RHEI and SuE models (Bockermann et al., 2000), or FUGI model (Brettel, 2003). 2) Indicator based statistical methodology Those models belong in this group which address the sustainability dimensions and apply a chosen structural criteria for selection of a core set of indicators, in order to asses sustainable path. As example the EPSILON project can be mentioned, where the sustainable development are benchmarked in European regions the on DPSIR framework (Blank et. al, 2005) 3) LCA based approaches Researches prooved that problemsolution applying life-cycle approach do not only have importance in assessing environmental impact and envirnomnetal performance or food safety but play a key role in measuring eco-efficiency. Moreover with the development of IO-LCA, if we can link the dynamic moving of material- and energyflows to economic data LCA creates the possibility for complex, new econometric measurement. (Tóthné Szita, 2007). This kind of application are the EVR modell (Hendriks és Brezet, 2009), CALCAS model Klöpffer (2008), EIO-LCA and REIO- LCA (Horváth és Hendrickson (1998) All these models had concidered the different dilemmas of sustainability measurement. The next figure represents the map of characteristics features of the analysed methods.

Figure 2.: Overview of sustainable development analysing models Source: Own compilation DILEMMAS OF MEASURING SD Unfortunately there is no methodology without uncertainty factors, or suspected inaccuracy. The characteristic dilemmas and uncertainties of the given estimations can be grouped into the following categories (see figure 2.)

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Figure 2: Main factors of sustainability dilemmas Source: own compilation Approach: Before developing the methodology and select the analysed dataset or choosing the appropriate indicators the clear definition of the sustainability is needed. While there are still arguments over what constitutes sustainable development indicator selection and development has started. By choosing a given approach led us to make decision about the scales or weighting of the different pillars, the complexity of the model, the level of the measurement, analysed indicators or required dataset. It also determines the limitations, the thresholds and the final results of the sustainability status. Indicators: There are number of initiatives working on indicators and frameworks for sustainable development (SD). Indicators and composite indicators are increasingly recognised as a useful tool for policy making and public communication in conveying information on countries’ performance. Index formulation raises the question of the method of normalisation, weighting, aggregation and in most cases answered by subjective judgments. . Statistics – Data: This factor includes the dilemmas of data collection, availability, aggregation, lack of data sources, and uncertainty of data. These are mainly generated by the following mentioned problems: o Lack of data – esp., environmental performance data: mapping the significant polluters in the region is time-consuming and expensive, so there is no complete, available data for the environmental pillar o There is no reliable data series for material and energy flows at regional level only at macro level, where the flows are measured only in monetary units. Input-output tables can be transformed to regional level by carefully selected methodology but it can be also the source of further risks. o Data gathering in case of company level - esp. in case of material and energy flows – can involve subjective data and opinions, o Administrative system border different than territory of environmental data collection o Administrative system border often changes and often different the territory of environmental and economic, social data collection Criteria of evaluation According to Kates (2001) and Snigh et al. (2009), the purpose of sustainability assessment is to provide decision-makers with an evaluation of global to local integrated nature–society systems in short- and long-term perspectives in order to assist them to determine which actions should or should not be taken in an attempt to make society sustainable (. But if we get the final (number) result of our analysis there is two question:

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• What can be considered sustainable? Can we assigne the risult to our contry’s targets? Do we know the thresholds, can we point out limits as a framwork for the wrong development path? • How can it be translated for the decision making actors? Simplification, communicative and easily undertsandable sustainability assesment is the only way to make them consider the predicted limits of economic and human activity. CONCLUSION In this paper we briefly summarized the main dilemmas of SD modell development based on the current available literature. This helped us to elaborate a demonstrative project to develop an LCA based I-O analysis methodology for SD performance evaluation. These are the two newest directions of the recent environmental performance analyses, so we can say that completing our mission the Hungarian LCA research can get in to the blood stream of LCA researches. The practical advantages also promising: the consequent environmental, social and economic evaluation of regional performance can support the regional decision making policy to help the region to catch up in a more sustainable rout. However the way to develop future scenarios for the region poses difficulties we have to face with the usual uncertainties: the lack of reliable statistical data, methodological implications the need for simplification. REFERENCES • Fullana, P.;, Betz, M., Hischier, R., Puig, R., (2009): Life Cycle Assesment Applications: Results from Cost Action 530, European Science Foundation, AENORediciones 15 pp • Pezzey, J. (1992): Sustainable Development Concepts – An Economic Analysis. Washington, D.C.: The World Bank. • WCED (1987): Our Common Future. Oxford: Oxford University Press. • Meadows, D. H. et al. (1972): The Limits to Growth. New York: Universe Books. • Hediger, W. (2004): Weak and Strong Sustainability, Environmental Conservation and Economic Growth. In: Natural Resource Modelling, Vol. (19), pp. 359–394. • Goodland, R. (1995): The Concept of Environmental Sustainability. In: Annual Review of Ecology and Systematics, Vol. 26 (1995), pp. 1–24. • van den Bergh, J. C.J.M. – Hofkes, M. W. (1997): A Survey of Economic Modelling of Sustainable Development. Amsterdam – Rotterdam: The Tinbergen Institute. • Bockermann, A., Meyer, B., Omann, I. J., Spangenberg, H. (2000): Modelling Sustainability with PANTA RHEI and SuE, Project on Modelling Sustainable Europe financed by EU DG XII, implemented by Wuppertal Institut, Wuppertal, and the Universities of Edinburgh, Tamper, and Madrid, pp 1-31 • Brettell, S., (2003): Econometric modelling in the evaluation of regional sustainable development, Cambridge Econometrics pp 1-9 • Singh, R. K., Murty, H.R., Gupta, S.K., Dikshit, A.K. (2009): An overview of sustainability assessment methodologies, Ecological Indicators 9(2009)18 pp.189-212. • WCED (1987): Our Common Future. Oxford: Oxford University Press. • Blanc, I., Friot, D., Margni, M., Jolliet O., (2005): Assessing Regional Sustainability with the EPSILON Project, Ecole Polytechnique Fédérale de Lausanne, Life Cycle Systems, CH-1015 Lausanne, Switzerland. pp1-9 • Klára Szita Tóth (2007): Életciklus-elemzés az elméleti alapoktól a gyakorlatig Habilitációs tézisek Miskolci Egyetem pp. 136

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FORMÁZÓSZEREK JELENLÉTÉNEK HATÁSA A TALAJOLDAT SZERVESANYAG-TARTALMÁRA Földényi Rita, Samu Gyöngyi, Tóth Zoltán Környezettudományi Intézet, Pannon Egyetem, 8200 Veszprém, Egyetem u. 10., Magyarország e-mail: [email protected] ABSTRACT The forming agents Supragil WP (anionic) and CTAB (cationic) were investigated in model soil solution systems because these compounds are frequently used in different products (pesticides, vaccines, cosmetics etc.) that can become environmental contaminants. The colloidal system was characterized by surface tension and zeta potential measurements. The humic substances form associates with both agents and the system is able to be stabilized either with negative (in case of Supragil) or with positive charge (in case of CTAB). This indicates the risk of the application of these compounds especially near either to the groundwater level or to any surface water. Adsorption of Supragil on different soils resulted in two-step of isotherms. The formation of two layers is indicated also by zeta potential measurements. BEVEZETÉS A gyógyszerek, növényvédőszerek (biológiailag aktív anyagok), de a kereskedelemben kapható, mindennapi életünkben használatos termékek (pl. kozmetikumok) is tartalmaznak formázószereket, amelyek segítségével az adott készítmény (formátum) a kívánt hatás elérésére alkalmassá válik. A formázószerek között sok felületaktív anyag és szerkezetileg velük rokon – amfipatikus – vegyület található, amelyek a vízbe és talajba jutva beláthatatlan következményekkel járó környezeti hatást válthatnak ki. A biológiailag aktív anyagok esetében döntően a hatóanyag sorsát igyekszünk nyomon követni, míg kevesebb figyelmet fordítunk az adalékokra. Inkább csak akkor ütközünk meg, amikor szerkezetileg hasonló (akár azonos) vegyületek olyan környezeti kárt okoznak mint pl. a Rába habzása, amelyet naftilszulfonát típusú bőrcserzéshez használatos anyag váltott ki. O Na

O

S

O

CH3

CH3

N CH3 Br

CH CH3

CH3

CH CH3 CH3

Supragil WP

CTAB

1. ábra: Két gyakran használt formázószer szerkezeti képlete A Supragil WP nevű, peszticidek diszpergálószereként ismert termék ugyanebbe a vegyületcsaládba sorolható, fő komponense az. 1. ábrán látható nátrium-diizopropil-szulfonát.

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Kisebb molekula, de szerkezetileg hasonló az anionos tenzidekhez, amelyeket bizonyos esetben még szennyezett talajok tisztításánál is alkalmaznak [1]. A kationos felületaktív anyagok közül a cetil-trimetil-ammónium-bromid, – amelynek közismert rövidítése a CTAB (1. ábra) – önmagában is antiszeptikus hatású [2], de adalékként használatos pl. vakcinában, hajkondícionálóban stb. [3,4]. Mindezekből következik, hogy a fent említett két formázószer (Supragil WP és CTAB) nagy eséllyel válhat környezeti szennyezővé, így a talaj és a felszín alatti víz szennyezőjévé is. A talaj szilárd fázisát szervetlen és szerves komponensek alkotják. Ez utóbbiak közül különleges szerepe van a humuszanyagoknak, amelyek élő szervezetek lebomlása eredményeként keletkező, kémiailag heterogén összetételű, funkciós csoportokban gazdag makromolekulás anyagok [5]. Polieletrolit jelleggel rendelkeznek [6], ami a hidrofób természetű, sok aromás gyűrűt tartalmazó vázon és annak oldalláncain található savas karakterű csoportok (–COOH, fenolos –OH) pH-függő disszociációjának köszönhető. Ennek következménye, hogy a talaj felületének ismerten negatív töltéséhez a humuszanyagok (HS) is hozzájárulnak, amelyek oldhatóságát a talajoldat (a talaj folyékony fázisa) fizikai tulajdonságai és összetétele határozza meg. Az oldott humuszanyagok a szennyezőként jelenlévő tenzidekkel asszociátumokat képezhetnek, amelyek stabilitása ugyancsak a talajoldat minőségi és mennyiségi jellemzőitől függ [5, 7, 8]. Jelen munkánk célja, hogy modell kísérletek révén megvizsgáljuk és összehasonlítsuk a fent említett két formázószer, az anionos Supragil WP és a kationos CTAB hatását a humuszanyagokra valamint három jellegzetes hazai talaj szervesanyag-tartalmára, aminek révén a valós környezeti hatások becsülhetővé válnak. ANYAGOK és MÓDSZEREK Anyagok Az oldatokat nagy tisztaságú, MilliQ vízzel (továbbiakban víz) készítettük. A foszfát-puffert nátrium-dihidrogén-foszfát és di-nátrium-hidrogén-foszfát bemérésével állítottuk elő, ami a Reanal Kft. terméke. A formázószerek közül a Supragil WP a RHODIA Geronazzo cégtől származik, míg a CTAB-t a Reanal Kft-től vásároltuk (1. ábra). A talajból kioldódó humuszanyagokat fulvosav (FA) illetve huminsav-nátriumsó (HANa) oldatával modelleztük. A fulvosav az Organit Kft-től származik, a huminsav-nátriumsó a Carl Roth GmbH+Co., Karlsruhe cég terméke. A talajkivonatok készítéséhez és a sztatikus egyensúlyi kísérletekhez három hazai talajt használtunk: homoktalajt, barna erdőtalajt és csernozjom talajt (legfontosabb jellemzőiket ld. az 1. táblázatban). Mindhárom minta a talaj felső 30 cm-es rétegéből származik. A mintavételt követően a talajokat légszáraz (23 ˚C) állapotba hoztuk, majd golyósmalomban őröltük. Kísérleteink során az 500 μm alatti mérettartománnyal dolgoztunk. Jellemzők

1. táblázat: A felhasznált talajok jellemzői Homoktalaj Barna erdőtalaj Csernozjom

Származási hely TOC (mg C/g talaj) pH

Dabrony 16,0 5,88

Tés 23,4 5,94

Vizsgált kolloid rendszerek

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Célunk elérése érdekében 0,01 mol/l koncentrációjú pH=7 foszfát-pufferrel talajkivonatokat valamint fulvosav (FA) és nátrium-humát (HANa) oldatokat készítettünk. Ez utóbbiak koncentrációját a talajkivonatokkal összehasonlítható szerves széntartalom alapján állítottuk be, ami a 20-100 mg C/l tartományban volt. A talajkivonatok készítésekor 1:10 szilárd talaj : foszfát puffer arányt alkalmaztunk. A szükséges mennyiségű (40 g) talaj bemérését követően hozzáadtuk az előzetesen elkészített foszfát-puffert (400 cm3), majd a szuszpenziót 1 órán át rázattuk 100-150 min-1 sebességgel. 24 óra állás után 3000 min-1 sebességgel 30 percen át centrifugáltuk, majd szűrőpapíron átszűrtük a mintát. A fenti talajkivonatok és HS-tartalmú oldatok szolgáltak a formázószerekkel készített kolloid rendszerek közegéül. Supragil WP esetében a vizsgált koncentrációtartomány: 10-5000 mg/l, míg a CTAB esetében 10-3000 mg/l.

ζ-potenciál meghatározása Az ily módon előállított kolloid rendszerek stabilitásának követésére módszerként a tömbfázisban jelenlévő töltéshordozó részecskék töltésállapotáról információt szolgáltató elektrokinetikai (ζ) potenciál meghatározását választottuk, amelyet a Malvern cég Zetasizer Nano series Zetasizer Nano-ZS műszerével (Pannon Egyetem, MÜKKI) végeztünk el. A mérés hibája ≤ ±1,6 mV. A rendszer stabilnak tekinthető, ha ζ értéke -20-25 mV-nál kisebb vagy +20-25 mV-nál nagyobb. Felületi feszültség (γ) mérése A formázószer kritikus micella képződési koncentrációját (cmc) és a vegyes aggregátumok képződéséhez rendelhető koncentrációkat (ún. kritikus aggregációs koncentráció: cac) [9] a levegő-oldat határfelület jellemzésére használatos felületi feszültség mérések segítségével First Ten Ångstroms tenziométerrel határoztuk meg. A mérés hibája ≤ ±0,5 mN/m. Adszorpciós vizsgálatok Talajszennyezés hatásának összetett vizsgálatára a sztatikus egyensúlyi kísérleteket választottuk, ahol a Supragil WP kiindulási oldatait 0,01 mol/l pH=7 foszfát-pufferrel készítettük. Ezek koncentrációja azonos volt a vizsgált kolloid rendszereknél megadott értékekkel. A kísérletekhez 5,000 g (m) talajmintát mértünk be, majd 5 ml pufferrel duzzasztottuk. Ezután hozzáadtuk az adott koncentrációjú (ci, mg/l), 45 ml térfogatú (V) Supragil WP-tartalmú oldatokat és a talajkivonatok készítésénél leírtakkal azonos módon rázattuk, állni hagytuk, majd centrifugáltuk és szűrtük. Az egyensúlyi koncentrációt (ce, mg/l) VARIAN UV-VIS Cary50 Conc nevű spektrofotométerrel mértük (λ=286 nm), majd ebből az (1) egyenlet segítségével számoltuk a fajlagos adszorbeált mennyiséget (q, mg/g). (1) V (ci − c e ) q= m Az egyensúlyi oldatok esetében elvégeztük a ζ-potenciál meghatározását is, majd összehasonlítottuk az adszorpció nélkül végrehajtott kísérletek eredményeivel. EREDMÉNYEK Adott kísérleti körülmények között a Supragil WP kisebb mértékben csökkentette a víz felületi feszültségét a HS jelenlétében, mint anélkül. A növekvő humuszanyag-koncentráció azonban e hatás ellen dolgozott, azaz átlagosan 320 mg/l Supragil koncentráció felett a növekvő HS-tartalom csökkenő γ-értékekhez vezetett. Mindez igazolja a Supragil-HS asszociátumok létrejöttét, amelyek között a hidrofób kölcsönhatás működik. A ζ-potenciál

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

értékek folyamatos csökkenése a rendszer stabilitásának növekedését jelzi, ami az egyre több negatív töltés taszító hatásának eredménye. Azonos eredményhez vezetett a talajkivonatokkal készített minták ζ-potenciál meghatározása is. Ekkor 1000 mg/l Supragil koncentráció felett a rendszer stabilitása rendkívül megnőtt az adszorpció nélküli vizsgálatok során, míg adszorpciót követően a stabilitás növekedése 3000 mg/l kiindulási Supragil koncentráció felett következett csak be. Tehát a talaj jelenlétében háromszoros mennyiségű formázószer eredményezett azonos veszélyt jelentő vízszennyezést. Azonban a barna erdőtalaj esetében az adszorpció során szemmel láthatólag is sok szerves anyag oldódott ki (szolubilizálódott) a szilárd fázisból, amit az is igazol, hogy a három talaj közül a ζ-potenciál alapján ebben az esetben a legnagyobb stabilitás (adszorpció nélkül a diagram viszont a két talaj között fut). A Supragil WP-vel elvégzett sztatikus egyensúlyi kísérletek mindhárom talajon kétlépcsős izotermát eredményeztek (2. a. ábra). Mindez kétrétegű adszorpcióra utal, ahol az első rétegnek még nem kell teljesen telítődnie ahhoz, hogy a második réteg kialakulása elkezdődjön. Az a törés (határkoncentráció), − ami valószínűleg azt jelzi, hogy a monomolekulás borítottság bekövetkezett, ezért már csak a második réteg telítése zajlik −, az mindenütt a 2500 mg/l kiindulási koncentrációhoz rendelhető, ahol egyébként a ζ-potenciál értékekben átmeneti csökkenés látható (2. b. ábra). A 2. lépcső a 3000 mg/l kiindulási Supragil koncentráció felett kezdi elérni a maximumát, ahol a rendszer stabilitása egyre nagyobb az egyre több negatív töltésű részecske taszításának következtében. A ζ-potenciál csökkenése jelzi a 2. adszorpciós réteg telítődését. Az adszorbeált mennyiséget tekintve egyértelműen látható, hogy a nagyobb szervesanyag-tartalmú talajok több Supragilt adszorbeáltak, ami a HS és a formázószer közötti hidrofób kölcsönhatás eredménye. 6

c e , mg / l

4 3

0

-25,00

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Csernozjom Barna erdőtalaj Homok

-30,00 ζ, mV

5

q, mg/gtalaj

-20,00

Csernozjom: Chi^2 = 0.01511 R^2 = 0.99752 Barna erdõtalaj: Chi^2 = 0.0592 R^2 = 0.99418 Homok talaj: Chi^2 = 0.02368 R^2 = 0.99514

2

-35,00

1 -40,00

0 0

1000

2000

3000 ce, mg/l

4000

5000

-45,00

b. Egyensúlyi oldatok ζ-potenciál értékei

a. Supragil WP adszorpciós izotermája három talajon

2. ábra: Supragil WP adszorpciója talajon (a.) és az egyensúlyi oldatok jellemzése (b.) A CTAB a fulvosav jelenlétében nagyobb mértékben csökkentette a víz felületi feszültségét, mint anélkül, míg a huminsav-nátriumsó jelenléte nem mutatott ilyen egyértelmű hatást. Ennek oka, hogy az FA több disszociábilis csoportot tartalmaz, mint a HA, tehát az ionpárképződés során több CTA-kation szükséges a semlegesítéshez, - így hidrofób asszociátum képződéséhez -, mint a huminsav esetében. HANa jelenléte átmeneti minimum (ca1), majd maximum (ca2) értéket is eredményezett a γ-log(cCTAB) diagramban. Ezek a törések különböző töltéssel rendelkező vegyes asszociátumok kialakulására utalnak, míg a CTAB cmc értéke HS jelenlétében növekszik. A minimum a negatív töltéssel rendelkező, míg a maximum a hidrofób, kifelé semleges asszociátumok képződésére utal, majd a CTA kation feleslege miatt

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várhatóan pozitív töltéssel rendelkező részecskék lesznek túlsúlyban. Ezeket a megállapításokat a ζ-potenciál értékek változása támasztja alá, miszerint a CTAB koncentrációjának növelése negatívból pozitívba történő áttöltést eredményezett. A görbe ahhoz az értékhez közel metszi az abszcisszát (ζ=0 mV), ahol a γ-log(cCTAB) diagramban a maximum látható, ezért a (ca2) érték valóban a hidrofób aggregátumokhoz rendelhető. Pl. 20 mg C/l HANa tartalmú oldat esetében ca2=200 mg/l, míg ugyanennél a HS-tartalomnál a ζ= 0, ha cCTAB ≅ 240 mg/l. Az eltérés oka, hogy a teljesen hidrofób aggregátumok csapadékot képeznek, ami a fenti mérések kivitelezését akadályozza. KÖVETKEZTETÉSEK A Supragil hidrofób kölcsönhatás révén asszociátumot képez a humuszanyagokkal, amelyeket képes a talajból oldatba vinni (szolubilizálni). A három talajjal kivitelezett sztatikus egyensúlyi kísérletek eredményeképpen a Supragil WP kétlépcsős izotermát eredményezett. A lépcsők két réteg kialakulását jelzik, amelyek telítődését az egyensúlyi oldatok ζ-potenciál értékeinek átmeneti, majd folyamatos csökkenése is jelez. A γ-log(cCTAB) és a ζ-cCTAB diagram egymással összhangba hozható értékeket eredményezett. A CTAB és a humuszanyagok között a semleges töltés elérését elektrosztatikus kölcsönhatás biztosítja, majd az így kialakult aggregátumok és a feleslegben jelenlévő CTAB hidrofób kölcsönhatás révén pozitív töltésállapotot eredményeznek, ezáltal a rendszer stabilizálódik. IRODALOMJEGYZÉK [1] [2] [3] [4]

[5] [6] [7] [8] [9]

Lee D-H., Cody R.D. (2001): Variation of soil hydraulic conductivity by anionic surfactants in soil column. Geosciences Journal 5, p. 287-291. Nakata K, Tsuchido T, Matsumura Y. (2011): Antimicrobial cationic surfactant, cetyltrimethylammonium bromide, induces superoxide stress in Escherichia coli cells. J Appl Microbiol. 110, p. 568-79. Singh M., Briones M., Ott G., O'Hagan D. (2000): Cationic microparticles: A potent delivery system for DNA vaccines. Proceedings of the National Academy of Sciences of the United States of America 97, p. 811-816. Chemistry in everyday life (letöltve: 2011. szeptember 13.), http://www.sakshieducation.com/(S(02brknadvm1omdqnalri0pql))/Inter/..%5CEAMCE T%5CQR%5CChemistry%5CSr%20Chem%5C16.Chemistry%20in%20Every%20day% 20Life_264-273_.pdf Tombácz E. (2002): A humuszanyagok határfelületi és kolloid tulajdonságai. Magyar Kémiai Folyóirat 108, p. 435-443. Tombácz E., Lámfalusi E., Szekeres M., Michéli E. (1996): Humuszanyagok hatása a talajok felületi tulajdonságaira. Agrokémia és talajtan, Tom. 45., p. 238-248. Tombácz E., Varga K., Szántó F. (1988): An X-ray diffraction stuy of alkylammonium humate complexes. Colloid Polym. Sci. 266, p. 734-738. Kördel, W. (1997.): Fate and effects of contaminants in soils as influenced by natural organic material. Chemistry International. 19, p. 136-140. Mészáros R. (2009.): Ellentétes töltésű polieletrolitok és tenzidek asszociációja, MTA doktori értekezés, ELTE Kémiai Intézet, Budapest

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CONFORMATIONAL ANALYSIS OF PHOSPHORUS POLYMERS WITH FLAME RETARDANT PROPERTY Simona Funar-Timofei, Smaranda Iliescu Institute of Chemistry of Timisoara of the Romanian Academy, Bul. Mihai Viteazu 24, 300223 Timisoara, Romania, e-mail: [email protected] ABSTRACT The phosphorous, halogen and nitrogen-containing polymers have excellent thermal stability and good flame retardant properties. In this paper the monomer structure of 4-(1,1,1,3,3,3hexafluoro-2-phenylpropan-2-yl)phenyl diphenyl phosphate was simulated by molecular mechanics calculations using the MMFF94s force field included in the Omega software. The conformations thus obtained were further minimized by the semiempirical RM1 method included in the MOPAC 2009 software The Omega conformation of minimum energy was energy optimized by the Hartree-Fock Self-Consistend Field (RHF) method, in order to obtain a stable structure. Structural compound features which characterize the most stable energetically conformations obtained by molecular mechanics and quantum chemical methods were compared with experimental data, yielding a unified structure. INTRODUCTION Phosphorus-containing polymers have been found in the last years to be technically interesting as engineering plastics, especially the phosphoric polyesters (polyphosphonates and polyphosphates) because of their excellent mechanical, electrical and flame resistance properties and also because of their analogy with the nucleic acids [1]. Also, the phosphorous, halogen and nitrogen-containing polymers are the most widely used, as commercial fireretardant polymers [2]. Multilinear quantitative structure-property relationships models for glass transition temperature of a series of polyphosphates and polyphosphonates were reported [3] using molecular mechanics and AM1 calculated descriptors for polymer dimers. R2 of 0.88 was obtained for 10 samples with the Sterimol B1 parameter and torsion angle C1, associated with packing preferences and the polymer backbone flexibility, respectively. It was found that a similar polymer structure derived from 4-[1,1,1,3,3,3-hexafluoro-2(4-hydroxyphenyl)propan-2-yl]phenyl phenyl phosphonate has the limiting oxygen index of 33 (%), being considered to have flame retardant property. In the literature X-ray experimental data of the similar triphenyl phosphate structure is reported [4]. Structural backbone features of this compound are compared to the studied compound. In this paper the monomer structure of the polymer derived from 4-[1,1,1,3,3,3hexafluoro-2-(4-hydroxyphenyl)propan-2-yl]phenyl phenyl phosphonate (Fig. 1) was simulated by conformational analysis using molecular mechanics and quantum chemical methods, in vacuum. The conformations of minimum energy thus obtained were analyzed in order to elucidate the most stable structure.

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8

9

16 23

29 O

Fig. 1. Structure of the 4-(1,1,1,3,3,3hexafluoro-2-phenylpropan-2-yl)phenyl diphenyl phosphate

17 F

30 O

O 28 P

38

F

19

13

31

O

22 15

14

7

6

F

11

26 21

5

20

1

25

24 18

12

27 F

F

10

4

F

2

METHODS Structure simulation by OMEGA software The molecular monomer structure of the diphenyl phosphate polymer derived from the 4[1,1,1,3,3,3-hexafluoro-2-(4-hydroxyphenyl)propan-2-yl]phenyl phenyl phosphonate was modelled by the conformational search ability of the Omega v.2.3.2 (OMEGA (version 2.3.2), OpenEye Science Software, 3600 Cerrillos Road, Suite 1107, Santa Fe, USA, 2008) program. SMILES notation was used as program input. The force field used was the 94s variant of the MMFF (Merck Molecular force field) [5] with coulomb interactions and the attractive part of the van der Waals interactions. For the generation of conformers, following parameters were used: a maximum of 200 conformers per compound, an energy cutoff of 10 kcal/mol relative to global minimum identified from the search and a RMSD fit value 0.6 Å was used to avoid redundant conformers. Structure simulation by MOPAC Structures of minimum energy obtained by molecular mechanics calculations were further minimized by quantum chemical calculations. Taking into account the big number of flexible bonds present in the compound skeleton, around which the rotation is quasi free, the semiempirical RM1 method [6] included in the MOPAC 2009 software (MOPAC 2009, James J. P. Stewart, Stewart Computational Chemistry, Colorado Springs, CO, USA, http://OpenMOPAC.net (2008)). was employed, with SCF convergence of 10-10, RMS gradient value of 0.01 kcal/Å·mol as criterion to choose an optimized conformation and the EF and PRECISE keywords. Structure simulation by Gaussian Gaussian 03W (Gaussian 03, Gaussian, Inc., Wallingford CT, 2004.) was used to model the structure of the 4-(1,1,1,3,3,3-hexafluoro-2-phenylpropan-2-yl)phenyl diphenyl phosphate. The Hartree-Fock Self-Consistend Field (RHF) method was employed, with 3-21G basis set for geometry optimization and frequency calculation. RESULTS AND DISCUSSION 148 conformers were found by Omega software for the 4-(1,1,1,3,3,3-hexafluoro-2phenylpropan-2-yl)phenyl diphenyl phosphate structure. Ten flexible angles were used in the conformational search. All these conformations were further minimized by the RM1 approach. Two conformers of very close energy were obtained by the RM1 method (see Table 1). The most stable energetically Omega conformer was, also, used in RHF minimizations.

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Table 1. Bond lengths (in Å) and torsion angles (in degrees) of macromolecule skeleton of minimum energy conformer obtained by different approaches Bond length

RM1

MMFF94s

RHF

X-ray

C23-O30 C22-O29 C24-O31 Average

1.36 1.36 1.35 1.36

1.37 1.37 1.36 1.37

1.40 1.40 1.39 1.40

1.46 1.42 1.36 1.41

O30-P38 O29-P38 O31-P38 Average

1.59 1.59 1.61 1.60

1.62 1.62 1.62 1.62

1.61 1.61 1.62 1.61

1.61 1.65 1.62 1.63

95.34 (+ac)* -87.42 (-sc)** -87.42 (-sc)* -90.6 (-ac)** 7.93 (sp)* 8.06 (sp)**

-0.01 (sp)

26.68 (sp)

0.01 (sp)

25.29 (sp)

-179.99 (ap)

-160.17 (ap)

-59.99 (-sc)

-38.96 (-sc)

-60.00 (-sc)

-37.79 (-sc)

-60.00 (-sc)

-32.53 (-sc)

-59.99 (-sc)

-45.36 (-sc)

-60.00 (-sc)

-45.99 (-sc)

Torsion angles C16-C23-O30-P38 C14-C22-O29-P38 C18-C24-O31-P38 C23-O30-P38-O28 C22-O29-P38-O28 C24-O31-P38-O28 C12-C21-C25-C20 C10-C20-C25-C21

118.61 (+ac)* 171.0 (ap)** 171.3 (ap)* 118.66 (+ac)** 28.19 (sp)* 28.10 (sp)** -44.26 (-sc)* -44.24 (-sc)** -45.74 (-sc)* -45.71 (-sc)**

*conformer obtained by the RM1 method, having the heat of formation of -441.624 kcal/mol **conformer obtained by the RM1 method, having the heat of formation of -441.6239 kcal/mol Following general structural features were derived from the inspection of the 4(1,1,1,3,3,3-hexafluoro-2-phenylpropan-2-yl)phenyl diphenyl phosphate minimized energy structure: a) The bond lengths around the phosphorus atom are closer to experimental X-ray data in case of Gaussian software conformer; b) Similar arrangements of the backbone torsion angles of conformers obtained by the MMFF94s force field and by the RHF method were observed. Eclipsed and trans arrangements of the Car-Car-O-P torsion angles were noticed in case of MMFF94s and RHF conformations. Closer arrangements (anticlinal and eclipsed) to the same X-ray torsion angle were observed in RM1 conformer; c) Gauche arrangement of the Car-O-P=O torsion angle could be found in the MMFF94s and RHF conformers. Eclipsed and gauche arrangements of the same torsion angle were observed in X-ray structure. The corresponding torsion angle of the RM1 structures have eclipsed and trans arrangements; d) Gauche arrangement of the Car-Car-C-Car torsion angles (between the phenyl rings) was observed. Conformations having the torsion angles around the P-O bonds in the ± gauche, ± eclipsed, or trans forms are considered to be acceptable, in accordance to X-ray experimental data of some organo-phosphorus compounds. Thus, this condition was fulfilled by all minimum energy conformers derived by all methods.

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CONCLUSIONS • • • •

Conformational analysis of a diphenyl phosphate was performed by molecular mechanics calculations employing the MMFF94s force field, by the semiempirical RM1 approach and the RHF method in order to obtain a consistent molecular structure. Torsion angles around the phosphorus atom had arrangements in agreement to X-ray data The conformer obtained by the RHF approach was closer to the experimental structure. This information is useful for further modelling of polymer flame retardancy property.

LIST OF REFERENCES [1] [2] [3] [4] [5] [6]

Sandler S.R., Karo W. (1974). Polymer Synthesis, Vol. 1, Academic Press, New York. Liaw D., Wang D.-W. (1996). Synthesis of fluorine-containing polyphosphates: Lowtemperature solution polycondensation of bisphenol AF and aryl phosphorodichloridates. Reactive & Functional Polymers, 30, p. 309-315. Funar-Timofei S., Kurunczi L. Iliescu, S. (2005). Structure-property study of some phosphorus-containing polymers by computational methods. Polym. Bull. 54, p. 443-449. Davies W. O., Stanley E. (1962). The crystal structure of triphenyl phosphate. Acta Cryst. 15, p. 1092-1097. Halgren T.A. (1999). MMFF VI. MMFF94s Option for Energy Minimization Studies. J. Comp. Chem. 20, p. 720-729. Rocha G.B., Freire R.O., Simas A.M., Stewart J.J.P. (2006). RM1: A Reparameterization of AM1 for H, C, N, O, P, S, F, Cl, Br, and I. J. Comput. Chem. 27, p. 1101 – 1111.

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CONFORMATIONAL ANALYSIS OF BICYCLIC PHOSPHATE DERIVATIVES BY COMPUTATIONAL METHODS Simona Funar-Timofei,a Gheorghe Ilia,a Daniela Ionescub a

Institute of Chemistry of Timisoara of the Romanian Academy, Bul. Mihai Viteazu 24, 300223 Timisoara, Romania, e-mail: [email protected] b “Victor Babes” University of Medicine and Pharmacy Timisoara, Faculty of Pharmacy, P-ta E. Murgu 2-4, 300034 Timisoara, Romania ABSTRACT Trimethylolpropane phosphate is an ethyl bicyclophosphate produced during the partial pyrolysis of certain synthetic, ester-based turbine lubricants supplemented with phosphatebased lubricity additives, being considered as having high toxicity. In this paper its structure was simulated by molecular mechanics methods using the OPLS, AMBER and MMFF94s force fields by the AM1 semiempirical approach and the Hartree-Fock Self-Consistend Field (RHF) method and results were compared with X-ray structure. Generally the generated structures obtained by these methods reproduced with accuracy the experimental data. The structure obtained by the RHF approach was closer to experimental data. INTRODUCTION Trimethylolpropane phosphate (TMPP, 4-ethyl-2,6,7-trioxa-1phosphabicyclo[2.2.2]octane 1-oxide (fig. 1) [1] is an ethyl bicyclophosphate produced during the partial pyrolysis of certain synthetic, ester-based turbine lubricants supplemented with phosphate-based lubricity additives [2]. TMPP has also been demonstrated to be formed through the partial pyrolysis of certain fire-retardant-treated urethane foams [3]. TMPP induces epileptiform activities in hippocampal CA1 neurons, and binds to the GABAAbenzodiazepine receptors [4]. It shows very low binding affinity for GABAB, nonadrenergic, dopaminergic, or cholinergic receptors [5]. The oral rat LD50 value of 3.08 mg/kg [6] includes TMPP in the category of highly toxic bicyclic phosphorus esters, according to the Hodge and Sterner scale [7]. In this paper the structure of TMPP was simulated by conformational analysis using molecular mechanics and quantum methods, in vacuum. The conformations of minimum energy thus obtained were compared to X-ray crystallography structure [8] of the same compound. The chosen method could be used further in structure-toxicity studies. 7 O P 11

8O O 9 1

O 10

2

3 4

Fig. 1. Structure of 4-ethyl-2,6,7-trioxa-1phosphabicyclo[2.2.2]octane 1-oxide

6 5

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METHODS Bicyclic phosphate structure simulation by OMEGA software The molecular structure of the title bicyclic phosphate was modelled by the conformational search ability of the Omega v.2.3.2 (OMEGA (version 2.3.2), OpenEye Science Software, 3600 Cerrillos Road, Suite 1107, Santa Fe, USA, 2008.) program. SMILES notation was used as program input. For the structure generation of conformers, following parameters were used: a maximum of 400 conformers per compound, an energy cutoff of 10 kcal/mol relative to global minimum identified from the search. The force field used was the 94s variant of the MMFF (Merck Molecular force field) with coulomb interactions and the attractive part of the van der Waals interactions. The RMSD fit value 0.1 Å was used to avoid redundant conformers. Bicyclic phosphate structure simulation by HYPERCHEM Bicyclic phosphate structure were built by the Hyperchem software (HyperChem 7.52 release for Windows; HyperCube, Inc., Gainesville, Florida, USA, http://www.hyper.com.) and conformational analysis was performed by molecular mechanics calculations, using the OPLS and AMBER force fields, with the RMS gradient value of 0.01 kcal/Å·mol as criterion to choose an optimized conformation, an acceptance energy cutoff of 20 kcal/mol above the minimum energy. Conformational analysis was, also, performed by the semiempirical AM1 method [9] with the RMS gradient value of 0.01 kcal/Å·mol, as criterion to choose an optimized conformation and Polak-Ribiere as conjugate gradient, an acceptance energy cutoff of 10 kcal/mol above the minimum energy, SCF convergence of 10-5. Bicyclic phosphate structure simulation by Gaussian Gaussian 03W (Gaussian 03, Gaussian, Inc., Wallingford CT, 2004.) was used to model the structure of the 4-ethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxide. The HartreeFock Self-Consistend Field method was employed, with 3-21G basis set for geometry optimization and frequency calculation. RESULTS AND DISCUSSION One conformation was obtained by each method. The respective optimized structures were superimposed on the corresponding unmodified X-ray structure [8] by a least-squares superimposition procedure (root-mean-square-deviation (RMSD) values are presented in Table 1). Only non-hydrogen atoms were matched. Averages were calculated for each type of bond and angle, for each minimum energy structure, as well as for the X-ray one. Standard deviations were computed in each case, with respect to the experimental data. Results are presented in Table 1 (bold values indicate the method with lowest standard deviation between average and experimental values).

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Table 1. Experimental and calculated bond lengths and angles of the optimized compound obtained by molecular mechanics and quantum chemical calculations AM1 AMBER RHF MMFF94s OPLS X-RAY P11-O8* P11-O9* P11-O10* Average Standard deviation

1.61 1.61 1.61 1.61 0.03

1.60 1.60 1.60 1.60 0.03

1.63 1.63 1.63 1.63 0.05

1.62 1.62 1.62 1.63 0.05

1.60 1.60 1.60 1.60 0.03

1.56 1.56 1.57 1.56

O8-P11-O9** O9-P11-O10** O10-P11-O8** Average Standard deviation

100.86 101.32 100.86 101.01 2.24

101.72 102.23 101.72 101.89 1.62

99.76 99.93 99.76 99.82 3.09

102.12 102.12 102.12 102.12 1.46

101.72 102.23 101.72 101.89 1.62

104.12 103.95 104.46 104.18

O8-C1* O9-C2* O10-C3* Average Standard deviation

1.41 1.41 1.41 1.41 0.04

1.43 1.43 1.43 1.43 0.02

1.46 1.46 1.46 1.46 0.00

1.43 1.43 1.43 1.46 0.00

1.43 1.43 1.43 1.43 0.02

1.46 1.46 1.46 1.46

O7-P11-O8* O7-P11-O9* O7-P11-O10* Average Standard deviation

117.07 116.95 116.95 116.99 1.87

116.23 116.30 116.30 116.28 1.36

117.99 117.93 117.93 117.95 2.54

116.08 116.09 116.09 117.95 2.54

116.23 116.30 116.30 116.28 1.36

114.36 114.67 114.03 114.35

P11-O7* Standard deviation

1.44 0.00

1.48 0.02

1.50 0.05

1.50 0.04

1.48 0.02

1.45

0.061 0.057 0.080 RMSD * bond length (in Å); ** bond angle (in degrees)

0.084

0.056

Calculated bond lengths and angles were in good agreement with the experimental ones. The obtained RMSD values obtained by the least-squares superimposition procedure of the optimized structure derived from the above mentioned methods over the experimental Xray one indicated that the optimized structure modelled by the Amber, OPLS and AM1 methods was in good agreement with the experimental one. CONCLUSIONS • • • •

Several optimization procedures were studied to obtain a consistent molecular structure of of 4-ethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxide. Conformational analysis was performed by molecular mechanics calculations employing the OPLS, Amber and MMFF94s force fields, the semiempirical AM1 approach and the ab initio RHF method. Generally the employed methods reproduced with accuracy the experimental X-ray data. Amber, OPLS and AM1 methods modelled better the the TMPP structure. The above presented results are useful for structure-toxicity relationships modeling.

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LIST OF REFERENCES [1] [2] [3] [4] [5] [6] [7] [8] [9]

Wadsworth W.S., Emmons W.D. (1962). Bicyclical Phosphites, J. Am. Chem. Soc. 84, p. 610 – 617. Centers P.W. (1992). Potential neurotoxin formation in thermally degraded synthetic ester turbine lubricants. Arch. Toxicol. 66, p. 679–80. Petajan J.H., Voorhees K.J., Packham S.C., Baldwin R.C., Einhorn I.N., Grunnet M.L., Dinger B.G., Birky M.M. (1975). Extreme toxicity from combustion products of a fire-retarded polyurethane foam. Science (Washington DC) 187, p. 742–744. Higgins G.M., Gardier R.W. (1990). Gamma-Aminobutyric acid antagonism produced by an organophosphate-containing combustion product. Toxicol. Appl. Pharmacol. 105, p. 103–112. Jung A.E., Narayanan T.K., Rossi III J., Ritchie G.D., Valenti P.J. (1995). Anatomical disposition, receptor binding and clearance of the neuroconvulsant trimethylolpropane phosphate (TMPP). Toxicology 15, p. 18–34. Kimmerle G., Eben A., Gröning P., Thyssen J. (1976). Acute toxicity of bicyclic phosphorus esters. Arch Toxicol. 35 (2), p. 149-152. Hodge H.C., Sterner J.H. (1949). Tabulation of toxicity classes. Am. Ind. Hyg. Assoc. J. 10, p. 93–98. Santarsiero B.D. (1992). Structure of an organic phosphate: O=P(OCH2)3CCH2CH3, Acta Crystallogr., Sect. C: Cryst. Struct. Commun. 48, p.699-701. Dewar M.J.S., Zoebisch E.G., Healy E.F., Stewart J.J.P. (1985). AM1: a new general purpose quantum mechanical molecular model. J. Am. Chem. Soc. 107, p. 3902-3909.

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AN ASSESSMENT OF HEAVY METALS CONTAMINATION OF SOILS AND VEGETATION NEAR AN AGROTEHNICAL FARM FROM AREA TIMIS Daniela Ionescu,1 Simona Funar-Timofei,2 Cristina Dehelean1 1

Department of Toxicology, Faculty of Pharmacy, University of Medicine and Pharmacy “Victor Babes” Timisoara, 2 Murgu E, 30004 2 Institute of Chemistry, Romanian Academy Bul. Mihai Viteazu 24, 300223 Timisoara, Romania, e-mail: [email protected]

ABSTRACT The objective of the study was the determination of the trace metal (Fe, Cr, Zn, Pb) status of soils and vegetables in the vicinity of a livestock (cattle, piggery, sheep and goat and poultry sections) using atomic absorption, spectrophotometry. Vegetable samples taken within the vicinity showed 0.85-0.190 mgkg -1 Fe, 0.356-0.549 mgkg-1 Zn,0.005-0.432 mgkg-1 Cr and 0.017-0.029 mgkg-1 Pb. Analytical results indicated that soils and vegetables values were below the WHO critical toxic levels. Statistically, there were significant correlations between trace metals concentrations of the test and control samples. The levels of trace metals were not considered to be toxic for human and animal uses. INTRODUCTION Environmental pollution nowadays is a big concern. Anthropogenic activities have altered the environment significantly throughout the world like mining, industry and agriculture [1]. Environmental contaminants are widely distributed in air, water and soils and, therefore, they will have an effect on the trophic chain (vegetables, animals and men) [2]. Heavy metals are of considerable behaviour [3]. Trace quantities of certain heavy elements, such as chromium, cobalt, copper, manganese and zinc are essential micronutrients for higher animals and for plant growth [4]. Lead (Pb), cadmium (Cd), and nickel (Ni) are significant environmental pollutants. Anthropogenic activities, such as agriculture, industry and urban life increase the Pb, Cd, and Ni contents of soils and waters and, therefore, have an effect on the metal contents of vegetables [5]. Vegetables absorb heavy metals from the soil as well as from surface deposits on the parts of vegetables exposed to polluted air [6, 7]. Moreover, the presence of heavy metals in fertilizers contributes an additional source of metal pollution for vegetables [8]. This study is aimed to examine the possible environmental pollution of the livestock vicinity. The soil and vegetable samples were analyzed to document the possible trace metal contamination arising from the poor work management practices in the area.

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MATERIALS AND METHODS Four sites (cattle, piggery, sheep and goat and poultry sections) on a livestock farm were selected in the Timis area. Twelve vegetable samples were collected from the centre of each site in September 2010. The vegetables were cleaned to remove visible soil and then washed with tap and distilled water several times, were allowed to drain, then were oven dried at 100 0 C for 10h. They were then ground in a Kenwood blender. A 5 cm of soil samples was collected from the immediate vicinity of the vegetable roots at depths of 0-10 and 10-20cm. Vegetable samples Two grams of each vegetable samples was ashed in a covered Teflon beaker using 20 cm3 of 1:1 HNO3/HCLO4 acid mixture followed by the addition of 3 drops of HF. This was heated to clear solution and continued until dryness. The cooled residue was dissolved in 5 cm3 concentrated HCL and the liquor was made up to 50 cm3 using distilled water. Soil samples One gram of the finely ground dried soil samples was mixed with 20 cm3 (1:1) HCL / HNO 3 acid mixtures and the content was heated until dryness. The residue was extracted using 2M HCL and brought it to 50 cm3 with distilled water. An SP 1900 atomic absorption spectrophotometer (AAS) equipped with an air–acetylene burner was used to determine the metal contents. Soil particle size fractions were quantitatively determined by the pipette method [9], soil pH values were measured in water [10]. The soil organic matter was measured using standard procedures [11]. Statistical analyses were performed with SPSS 10. The transfer factor (TF) was computed as the ratio of the concentration of metals in vegetables to that in the soil. RESULTS AND DISCUSSION The results of the trace metals analysis of soil and vegetable samples of depths of 0-10 and 10–20 cm are recorded in Table 1. Cattle, piggery and poultry section presented high concentrations of trace metals in the soil at depth of 0-10cm than other depth, while depth of 10–20cm exhibited low concentrations of these metals. Iron and Zinc were found to be the most abundant metals in the samples. The sequence of metal concentrations in the samples was Zn> Fe> Cr> Pb for cattle and poultry sections and Zn> Fe> Pb> Cr for sheep, goat and piggery sections. The concentrating of metal in vegetables harvested in the livestock soils revealed that trace metal uptake is plant – species dependent. The results obtained here were in agreement with other results [12 -14].

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Table 1. Metal contents of soils and vegetables analyzed (mgkg-1) Location Cattle Section

Control Poultry Section

Control Piggery

Sample Fe Zn Cr Pb 0-10cm 0.617 0.835 0.021 0.052 10-20cm 0.245 0.687 0.013 0.074 vegetable 0.069 0.648 0.035 0.013 0-10cm 10-20cm

0.069 0.767 0.023 0.038 0.405 0.688 0.524 0.022

vegetable 0-10cm 10-20cm vegetable

0.159 0.278 0.157 0.259

0.497 0.729 0.538 0.658

0.433 0.025 0.006 0.051

0.022 0.024 0.053 0.037

0-10cm 0.099 0.578 0.053 0.088 10-20cm 0.447 0.438 0.075 0.153 vegetable 0.158 0.559 0.103 0.016 0-10cm 10-20cm

0.189 0.668 0.032 0.047 0.119 0.679 0.021 0.087

Section vegetable 0.259 0.599 0.034 0.023 0-10cm 0.358 0.569 0.014 0.025 Control

10-20cm 0.378 0.419 0.025 0.017 vegetable 0.095 0.357 0.018 0.059

Sheep and goat 0-10cm 10-20cm Section vegetable 0-10cm 10-20cm Control vegetable

0.149 0.127 0.201 0.218 0.289 0.199

0.357 0.426 0.319 0.627 0.688 0.526

0.012 0.024 0.021 0.017 0.039 0.015

0.045 0.067 0.019 0.048 0.077 0.023

p < 0.001

CONCLUSION • • •

Trace heavy metals were analyzed in livestock environment. Low values were found in soils and vegetables around the vicinity. It is worthy of note that they were below the WHO permissive levels [15]. However, it is suggested that regular monitoring of the vicinity should be encouraged this is just to avoid possible consumption of contaminated plant and water.

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REFERENCES [1] [2] [3] [4] [5] [6] [7] [8]

[9] [10] [11] [12] [13] [14] [15]

Wang P.F., Zhang S.H., Wang C., Hou J., Guo P. C., Lin Z.L. (2008). Study of heavy metal in sewage sludge and in Chinese cabbage grown in soil amended with sewage sludge. African J. Biotech. 7(9), p. 1329-1334. Tiller K.G. (1989). Heavy metals in soils and their environmental. Advan. Soil Sci. 9, p. 113-142. Omgbu J.A., Kokogbo M.A. (1993). Determination of Zn, Pb, Cn and Hg in soils of Ekpan, Nigeria. Environ. Int. 19, p. 611-612 Somers E. (1974). The toxic potential of trace metals in foods: A review. J. Food Sci. 39, p. 215-217. Alegria A., Barberfi R., Boluda R., Errecalde F., Farr R., Lagarda M.J. (1991). Environmental cadmium, lead and nickel contamination: possible relationship between soil and vegetable content. Fresenius J. Anal. Chem. 339, p. 654-657. Buchaver M.J. (1973). Contamination of soil and vegetation near zinc smelter by zinc, cadmium, copper and lead. Environ. Sci. Technol. 7, p.131-135. Haghiri F. (1973). Cadmium uptake by plants. J. Environ. Qual. 2, p. 93-96. Yusuf A.A., Arowolo T.A., Bamgbose O. (2003). Cadmium, copper and nickel levels in vegetables from industrial and residential areas of Lagos City, Nigeria. Food Chem. Toxicol. 41, p. 375-378. Day P.R. (1965). Particle fractionation and particle size analysis. In: Methods of soil analysis. ed. Black C.A., American Society of Agronomy, Maidison, Wisconsion, p. 545-567. Avery B.W., Bascomb C.C. (1974). Soil survey methods. Soil survey Technical Monograph No 6. Rothamsted Experimental Station, Harpenden, UK. Hesse P.R. (1971). A textbook of soil chemical analysis. John Murrary, London. Hooda P.S., McNulty D., Alloway B.J. Aitken M.N. (1997). Plant availability of heavy metals in soil, previously amended with heavy application of sewage sludge. J. Sci. Food Agr. 73, p. 446- 454. Oyedele D.J. Obioh I.B., Adejumo J.A., Oluwole A.F., Ania P.O., Asubiojo O.I.(1995). Lead contamination of soils and vegetation in the vicinity of a lead smelter in Nigeria. Sci. Total Environ. 172, p. 189-195. Rashed M.N., Awadallah R.M. (1998). Trace elements in Faba bean (Vica faba L) plant and soil as determined by atomic absorption spectrophotometer and iron selective electrode. J. Sci. Food Agric. 77, p. 18-24. FAO/WHO (1976). List of maximum levels recommended for contaminants by the Joint FAO / WHO Codex Alimentaries Commission. 2nd series. CAC/FAL, Rome, 3 p. 1-8.

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A FÓLIA ALATTI TERMESZTÉSBŐL SZÁRMAZÓ FŰSZERPAPRIKA ŐRLEMÉNYEK FONTOSABB BELTARTALMI ÉRTÉKEINEK ALAKULÁSA THE FORMATION OF THE MAIN CONTENTS OF GROUND SPICE PEPPER CULTIVATED UNDER PLASTIC COVER Nagy Kitti1 – Tímár Zoltán2 – Kis Krisztiánné1 – Dr. Slezák Katalin1 1.

Budapesti Corvinus Egyetem, Kertészettudományi Kar, Zöldség- és Gombatermesztési Tanszék, 1118 Budapest, Villányi út 29-43. ([email protected]) 2. Fűszerpaprika Kutató-Fejlesztő Nonprofit Közhasznú Kft. 6300 Kalocsa, Obermayer tér 9. ABSTRACT A hajtatott fűszerpaprika kísérletet a BCE Kertészettudományi Kar Kísérleti Üzeme és Tangazdaságában állítottuk be, nagylégterű fóliasátorban, Délibáb (folytonnövő) hibriddel, konténeres termesztésben. Támrendszeres művelésmódot alkalmaztunk, kétszálas metszéssel, 4 tő/m2 növénysűrűséggel. Augusztustól novemberig, 8 szedést végeztünk. Vizsgáltuk a termésekből készült őrlemény cukor- és festéktartalmát. Az összes cukortartalom növekvő tendenciát mutatott a tenyészidő során, míg a festéktartalom, a cukortartalom növekedésével párhuzamosan csökken. ABSTRACT The experiment of the forced spice pepper were set in a large space polytunnel with „Délibáb” (ever-growing) hybrid in a containered cultivation. It presented in the Research and Experimental Farm of Corvinus University of Budapest, Faculty of Horticultural Sciences. Trained cultivation and 4 root/m2 plant consistence were used and pruned to 2 stems. There was 8 harvest from August till November. The sugar- and pigment content of the fruit’s ground were analysed. The total sugar content were increased during the growing season, the decreasing pigment content was parallel with the increasing sugar content. BEVEZETÉS A 2010-es termelési adatok alapján, a fűszerpaprika termesztési felülete 25%-al csökkent az előző évhez képest (2000ha-ról 1500ha-ra) (FruitVeb 2010). A csökkenést ökológiai és gazdasági változások eredményezték. A klímaváltozás miatt a hagyományos fűszerpaprikatermesztés (szabadföldi, helyrevetett vagy palántázott) kockázata nőtt, a minőségi értékek sem alakulnak ki olyan magas szinten, mint védett, és szabályozott körülmények között. Erre megfelelő termesztéstechnológiai eljárásnak bizonyulhat a fólia alatti termesztés, ami korábbi szedéskezdetet, többszöri szedést, jobb szedési minőséget (elsősorban tisztaságot), jobb (és olcsóbb) utóérlelést, így jobb minőségű őrleményt jelenthet. Különösen fontos ez a hazai időjárási viszonyok mellett, ahol a korai fagyok vagy a túl sok csapadék a termelőt gyakran arra kényszerítik, hogy a termést a teljes érés előtt leszedje.

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A fólia alatti, hajtatásos termesztéstechnológia fő kérdései közé sorolható az állománysűrűség, metszésmód, támrendszer és a szedések gyakoriságának jelentősége. Az állománysűrűség 4-4,5-5 tő/m2 között elegendő lehet (Zatykó - Márkus, 2006). A metszésmód és támrendszer kialakítása összefüggésben van az állománysűrűséggel, meghatározza a növények fényellátottságát, a mikroklímát, a növényvédelmet és a szedések számát. A többszöri szedés növeli a termés összmennyiségét, mivel az érett termések eltávolításával a növényeket tehermentesítjük, ezzel lehetőséget adva újabb termések jó minőségben való kineveléséhez, beérleléséhez (Durovka et al., 2006). A beltartalmi értékeket a termesztéstechnológia több tényezője befolyásolja, kezdve a tápanyag-utánpótlástól egészen a betakarítás időzítéséig (Irinyi – Slezák, 2006a,b.; Gyökös et al., 2009). A fűszerpaprika legfontosabb alkotóelemei közé sorolhatóak: víz, színezékanyagok, kapszaicin, vitaminok, zsírsavak, fehérjék, illatanyagok, antioxidánsok, ásványi anyagok és a szénhidrátok. A szénhidrátok – köztük a cukor – az őrlemény jellegzetes zamatának, ízének kialakításában játszanak szerepet. A cukor nagyobbrészt fruktóz és glükóz, de kimutatták a szacharóz jelenlétét is. Mennyiségük erősen függ az érési stádiumtól, fajtától, időjárási viszonyoktól (Somos, 1985). A beltartalmi értékek kialakulása hosszú folyamat, amely két részre osztható. A termésérés kezdetétől a betakarításig alakul ki a termésfal cukortartalma teljes egészében, a termésfal színezék 50-60%-ban, az olaj- és illóolaj tartalom 75%-ban és a teljes C-vitamin tartalom. Az utóérlelés első fázisa alatt alakul ki a karotin-tartalom és az egyéb vitaminanyagok teljes mennyisége (Márkus - Kapeller, 1990). A festék (karotinoid) szintézis a paprikában a pirosra érést megelőzően két héttel indul meg, a termésfal színváltozása kíséri. Az összes cukortartalom a pirosra éréskor vagy az azt megelőző héten éri el a maximumát és innentől kezdve a festéktartalom növekedésével párhuzamosan csökkenni kezd. Ekkor a cukrok olyan szerves savakká bomlanak, melyek egy része a légzés során, más része a festék-szintézis céljaira használódik el. A csípős fajták összes cukortartalma 18-20% (szárazanyagban), a nem csípős fajtáké 22-25%. A paprika pirossá érése és a feldolgozás megkezdése közötti időszakot a paprika utóérlelésének nevezzük. A megfelelő utóérlelés során a természetes szikkadás hatására a nedvességtartalom csökkenésével a cukortartalom is csökken, a paprika klorofill tartalma teljes egészében átalakul piros és sárga színezékké, illetve az összes színezéktartalmon belül növekszik a piros színezékek aránya. Tehát ekkor stabilizálódnak a paprika minőségét döntően meghatározó karotinoidok és aroma anyagok. (Krajayklang et al., 2000; Márkus et al., 1999; Márkus - Kapitány, 2001; Vastag, 2003). Ebben a közleményben a többéves kísérletsorozat első évének eredményeiről számolunk be, azon belül az őrlemények cukor- és festéktartalmának változását vizsgáljuk, a szedési időpontoknak megfelelően. ANYAG és MÓDSZER A kísérletet a BCE Kertészettudományi Kar Kísérleti Üzeme és Tangazdaságában állítottuk be, nagylégterű fóliasátorban, Délibáb (folytonnövő) hibriddel, konténeres termesztésben. A palántanevelés 96-os KITE tálcában folyt (400 tő/m2), POT 20 jelű palántaföldben, április 1-i magvetéssel. Az ültetésre május 20-án került sor, 4 tő/m2-es növénysűrűséggel. A konténereket ikersorban helyeztük el (90+60x32 cm növény térállás) és a szárakat függőlegesen vezettük fel, kétszáras metszésmóddal. Négy párhuzamos ismétlést alkalmaztunk. Csepegtető öntözésre-tápoldatozásra, a növények igényei szerint volt lehetőség. A fitotechnikai munkák során a kétszálas alakító metszést követően a főhajtásokat zsineg köré tekertük, és csak a kihajló oldalhajtásokat törtük vissza, 2-3 ízköz után. A fóliasátorban

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megelőző növényvédelmet folytattunk. (Emiatt károsító szervezetek okozta terméskiesést nem tapasztaltunk). A szedéseket augusztus elejétől kéthetente végeztük (08.04., 08.18., 09.01., 09.15., 09.29., 10.13., 10.27., 11.10.), a termések biológiai érettségi állapotában. A szedést követően külön válogattuk az egészséges, valamint beteg (Ca-hiányos) bogyókat. A vizsgálatokat az egészséges termésekkel folytattuk. A fűszerpaprika termések 4 hetes utóérlelés után kerültek őrlésre. Az utóérlelés – a termesztési gyakorlatnak megfelelően – az augusztus-szeptemberi szedéseknél árnyékolt fóliasátorban, a későbbi szedéseknél szobahőmérsékletű helyiségben történt. A cukortartalom vizsgálatát a BCE Kertészettudományi Kar Zöldség- és Gombatermesztési Tanszék kutató laboratóriumában végeztük el. A meghatározás a Luff-Schoorl módszerrel történt. A módszer segítségével kimutatható az egyszerű cukrok, majd savas hidrolízis után az összes cukor mennyisége. Az utóérlelt festéktartalom meghatározása az MSZ 9681-5:2002 előírásának megfelelően történt az ASTA (American Spice Trade Association) módszer elve alapján. A vizsgálatra a kalocsai Fűszerpaprika Kutató-Fejlesztő Nonprofit Közhasznú Kft. laboratóriumában került sor. EREDMÉNYEK és KÖVETKEZTETÉSEK A szedések során, az első időpont kivételével, az általános 18% feletti összes cukortartalmat mértük (1. ábra). Az augusztus illetve a szeptember eleji szedések esetében kaptuk a legalacsonyabb értékeket (21,6% és 22,9%), azonban a festéktartalom ekkor volt a legmagasabb, 261 ASTA (2. ábra). Az utolsó szedés őrleményében magasabb, mint 34% összes cukortartalmat mértünk. Ez a kiugróan magas érték annak köszönhető, hogy az utóérlelés során, ebben az időszakban kevesebb festék szintetizálódott. 40 35 30

%

25 20 15 10 5 0 08.04.

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150 100 50 0 08.04.

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10.27.

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2. ábra: A festéktartalom alakulása a szedések során A vizsgálatsorozat egyértelműen megmutatta, hogy a szedés időpontjának, valamint valószínűsíthetően az utóérlelés időszakának körülményei (hőmérséklet, fény viszonyok) nagymértékben befolyásolják a fűszerpaprika őrlemények cukortartalmát és a színanyagok kialakulását. A kutatómunkát a TAMOP-4.2.1/B-09/1/KMR-2010-0005 támogatja. IRODALOMJEGYZÉK 1. Durovka, M., Lazić, B., Bajkin, A., Potkonjak, A., Marković, V., Ilin, Ž., Todorović, V. (2006): Proizvodnja povrća I cveća u zaštićenom prostoru. Grafomark, Laktaši, Bosnia. ISBN 86-7520-087-0 p. 510. 2. FruitVeb (2010): A zöldség és gyümölcs ágazat helyzete Magyarországon. Magyar Kertészeti Tanács, Budapest. 3. Irinyi B., Slezák K. (2006a): Lombtrágyázás hatása a fűszerpaprika termésmennyiségére és minőségére. Zöldségtermesztés, 37(3): 24-28. 4. Irinyi B., Slezák K. (2006b): Lombtrágyázás hatása a fűszerpaprika fontosabb beltartalmi tulajdonságaira. Magyar Táplálkozástudományi Társaság XXXI. Vándorgyűlése. Keszthely, 2006. október 5-7. Proc. 35. 5. Krajayklang, M., Klieber, A., Dry P. R. (2000): Clour at harvest and post-harvest behaviour influence paprika and chilli spice quality. Postharvest Biology and Technology 20: 269-278. 6. Márkus, F., Daood, H. G., Kapitány, J., Biacs, P. A. (1999): Change in the carotenoid and antioxidant content of spice red pepper(paprika) as a function of ripening and some technológical factors. Journal of Agricurtural and Food Chemistry, 47(1): 100107. 7. Markus F., Kapeller K. (1990): A genetikai koraiság fokozásának jelentősége a magyar fűszerpaprika nemesítésében. ZKI Bulletin Vol. 23. p. 89-94. 8. Márkus F., Kapitány J. (2001): A fűszerpaprika termesztése és feldolgozása. Mezőgazdasági Szaktudás Kiadó, p. 112. 9. Somos A. ( 1985): A paprika. Akadémiai Kiadó, p. 386. 10. Vastag J. (2003): Az utóérlelt paprika színanyaga megduplázódhat. Biokultúra, (14)5: 8-9. 11. Zatykó L., Márkus F. (2006): Étkezési és fűszerpaprika termesztése. Mezőgazda Kiadó, Budapest. ISBN: 9789639624481.

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THE EFFECT OF UV RADIATION ON THE MYCELIA GROWTH OF WHITE BUTTON MUSHROOM AND THE PATHOGENIC FUNGI OF CULTIVATED MUSHROOMS Anna Szabó, Júlia Győrfi Corvinus University of Budapest, Faculty of Horticultural Sciences, Department of Vegetable and Mushroom Growing, H-1118 Budapest, Villányi str. 29-43., Hungary e-mail: [email protected] ABSTRACT Agaricus bisporus (LANGE/IMBACH) is the most commonly cultivated edible mushroom of the world. Hungarian production of this species takes place mainly in limestone cellars and in no longer used stables. In most of these facilities the growing conditions are not always optimal; it is difficult to face the hygienic regulations and to ensure effective prevention. Two pathogenic fungi – Verticillium fungicola var. fungicola PREUSS (dry bubble disease) and Mycogone perniciosa MAGNUS (wet bubble disease) – are the most serious diseases occurring during the growing period. The sterilizing ability of UV radiation is well known. In our experiment the effect of UV light on the in vitro tissue culture of white button mushroom and the two diseases were examined. The aim of the study was to determine which UV light range and irradiation time is more effective against the two pathogens. With proper application, UV irradiation could function as an additional technique in mushroom protection, by preventing diseases in growing houses and cellars. INTRODUCTION Agaricus bisporus (LANGE/IMBACH) is the most commonly cultivated edible mushroom of the world (FruitVeb, 2010). In Hungary, the cultivation of this species takes place mainly in limestone cellars and in no longer used stables. In the recent years, many technological improvements were introduced. Growers started using new hybrid strains with higher productivity, improved casing soil mixtures, and the usage of Phase III. compost became widely common as well (Győrfi, 2002). As most of the Hungarian growing facilities have been in operation for decades now without any technological modernization – many of them are not properly air-conditioned, and the growing conditions are not always optimal –, it is difficult to face the hygienic regulations (Győrfi, 2010). Two pathogenic fungi – Verticillium fungicola var. fungicola PREUSS and Mycogone perniciosa MAGNUS – are the most serious diseases occurring during the growing period (Aponyiné et al., 1998; Fletcher – Gaze, 2008). In order to prevent their appearance, growers disinfect the rooms, sterilize the equipment, minimize human contact with the growing materials and use certain chemicals against mushroom flies which act as vectors of diseases (Rácz – Koronczyné, 2003, Győrfi, 2008a, b). There are only a few chemicals which can be used against pathogens in mushroom cultures, thus it is necessary to focus on prevention (Győrfi, 2003). Before new crop, growers disinfect

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the growing area, the surfaces and the equipment. They apply vector nets to prevent appearance of mushroom flies (Sciaridae and Phoridae) and other insects (Szili, 2008, Győrfi, 2009). Years of experience prove that in the traditional growing houses these mushroom protecting procedures are not effective enough by themselves; additional methods should be brought into the production. There are ongoing researches focused on using UV radiation for enhancing the vitamin D content of mushrooms in the Department of Vegetable and Mushroom Growing. Part of this research is to examine the effect of UV light on the in vitro tissue culture of cultivated and pathogenic fungi. The sterilizing ability of UV radiation is well known, UV lamps are already used in laboratories for sterile work. In addition to the current mushroom protecting technologies, applying UV irradiation in the growing areas can enhance effectiveness. It is optimal for sterilizing materials like casing soil, which is often the source of the dry and wet bubble disease, or equipment which come contact with the mushroom culture. The aim of the study was to determine which UV light range is more effective against Verticillium fungicola var. fungicola and Mycogone perniciosa, and to define the optimal irradiation time period for the two pathogens MATERIALS and METHODS The experiment was conducted in a laboratory, under controlled conditions. The source of the cultivated mushroom and the two pathogens used in the study was the culture collection of the Department of Vegetable and Mushroom Growing. Two wavelengths of the UV range were used: a Vilbert Lourmat 115M type UVB lamp operating on 312 nm and one on 245 nm were set up in a laboratory on a special stand, where the distance of the radiation source and the tissue culture can be adjusted. For the growing substrate, 20 grams of agar-agar and 20 grams of malt extract were dissolved in 1 liter water. The solution was then sterilized in high pressure chamber on 121°C for 20 minutes. 39-39 pieces of 9 cm Petri-dishes was then filled with the growing substrate. The pathogens were inoculated on the Petri-dishes. After 16 days incubation, the widest and narrowest diameters of the tissue cultures were measured with caliper. Both pathogens were irradiated in 3 repeats, on the two wavelengths. 6 different time periods (5, 10, 15, 20, 25 and 30 minutes) were applied in 3 repeats, this way the tissue cultures got 15, 30, 45, 60, 75 and 90 minutes irradiation. 24 hours passed between each repeat, for this time, the tissue cultures were incubated on 25°C. Diameters of the treated and untreated (control) cultures were measured before the first, and after the second and third treatments RESULTS Diagram 1, 2 and 3 shows the changes in the tissue growth of the three species after UV treatments. The horizontal axis shows the different time lengths of treatments, while the growth in percentage is shown on the vertical axis. The total growth of the treated tissue cultures in percentage is correlated to the growth of the untreated control. On Diagram 1 we can see that UVB treatment caused a significant negative effect on mycelia growth of Verticillium fungicola var. fungicola. Even the shortest irradiation time (15 min) caused a 25 % setback compared to the growth of the untreated control. The culture treated for the longest time (90 min) became only the size around 20 % of the control. It can be seen that although every irradiation time period made the cultures grew significantly slower, no

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reverse proportionality can be drawn, since for example the 75 minutes treated cultures grew stronger than the 45 or 60 minutes treated. Similar tendency can be observed in case of UVC treatments. 15 minutes of UVC irradiation caused a much effective setback than UVB irradiation. In this case, the cultures grew only to the size around 18 % of the control. By the end of the third day, the treated tissue cultures were 10 times smaller than the untreated ones. Data on Diagram 2 shows similar tendencies in case of Mycogone perniciosa. UVC proved to be better in blocking mycelia growth. The longest irradiation time had the most negative effect in case of both wavelengths. Diagram 1, 2. The effect of UVB and UVC irradiation on the growth of Verticillium fungicola var. fungicola and Mycogone perniciosa tissue cultures

The mycelia growth of Agaricus bisporus is effected differently by UV irradiation. Due to data showed on Diagram 3, the mycelium of this cultivated mushroom is not as sensitive as the mycelia of dry and wet bubble disease. Not even the longest irradiation time can cause as much setback in tissue growth as it was seen in case of the pathogens. Another important difference is that UVB radiation proved to be more effective on three time periods (45, 60 and 75 minutes. The difference between each treatment is not as significant as in case of the pathogens mentioned before. Diagram 3. The effect of UVB and UVC irradiation on the growth of Agaricus bisporus tissue cultures

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CONCLUSION Data shows that in case of both pathogens (irradiated on both wavelengths and for any time period), UV treatment caused significant setback in tissue-growth. UVC irradiation proved to be more efficient, as it caused 73,1-90,4% decline, while the UVB treated tissues grew only 24,4-80,2% less, than the untreated control. The two pathogens reacted the same; the rate of setback in tissue growth was similar. UV irradiation effects the mycelia growth of the cultivated mushroom, Agaricus bisporus as well. If UV is applied in mushroom growing it is important to protect the compost, and only irradiate other materials (eg. casing soil) and the equipment. Due to the data, both UV ranges are capable of significant inhibition of tissue growth. With correct application (proper irradiation time and distance), UV irradiation could function as an additional technique in mushroom protection, by preventing diseases in growing houses and cellars. LIST OF REFERENCES 1. Aponyiné, Garamvölgyi I., Győrfi J., Nagy G., Reiderné, Saly K. (1998): A csiperkegomba növényvédelme. Növényvédelem, 34 (8): 437-442. 2. Fletcher, J.T., Gaze, R.H. (2008): Mushroom Pest and Disease Control, a Colour Handbook. Manson Publishing, Boston. 3. FruitVeb (2010): A zöldség és gyümölcs ágazat helyzete Magyarországon. Magyar Kertészeti Tanács, Budapest. 4. Győrfi J. (2002): A magyar gombatermesztés helyzete és a fejlesztés lehetőségei. PhD értekezés. Szent István Egyetem, Kertészettudományi Kar, Budapest. 5. Győrfi J. (2003): Csiperketermesztés nemcsak vállalkozóknak. Szaktudás Kiadó Ház, Budapest. 6. Győrfi J. (2008a): A csiperke száraz mólé betegsége. Kertészet és Szőlészet. 57 (51-52): 10-11. 7. Győrfi J. (2008b): A csiperkegomba nedves mólé betegsége. Kertészet és Szőlészet. 57 (41): 11-13. 8. Győrfi J. (2009): Gombaszúnyogok kártétele a csiperketermesztésben. Kertészet és Szőlészet, 58 (14): 6-8. 9. Győrfi J. (2010): Gombabiológia, gombatermesztés. Mezőgazda Kiadó, Budapest. 10. Rácz J., Koronczy I.-né (2003): Ehető gombák termesztése, Országos Korona Gombaipari Egyesülés, Eger 11-16, 114. 11. Szili I. (2008): Gombatermesztők könyve. Mezőgazda Kiadó, Budapest. The results presented here are an output from research fund VITADFUN (TECH_08/2008) supported by NKTH.

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A CSAPVÍZTŐL A GLIKOLIG, A KÖRNYEZETI LEVEGŐTŐL A FÖLDGÁZIG; BENZOL ÉS TOLUOL KONCENTRÁCIÓ MEGHATÁROZÁS SZÉLES DINAMIKUS TARTOMÁNYBAN Hanyecz Veronika1, Mohácsi Árpád2, Utry Noémi1, Puskás Sándor3, Vágó Árpád3, Szabó Gábor1 1

Szegedi Tudományegyetem, Optikai és Kvantumelektronikai Tanszék, 6720 Szeged, Dóm tér 9. 2 Magyar Tudományos Akadémia Lézerfizikai Tanszéki Kutatócsoport, 6720 Szeged Dóm tér 9. 3 MOL Magyar Olaj- és Gázipari Nyrt., 6701 Szeged Pf. 37.

ABSZTRAKT Az előadásban egy olyan, fotoakusztikus detektáláson és kromatográfiás elválasztáson alapuló mérési mód kerül bemutatásra, amellyel folyadék és gázmintákban széles dinamikus tartományban lehet benzol és toluol koncentrációt meghatározni. A mérési módszert kipróbáltuk környezeti levegő, valamint vízmintákban. A laboratóriumi asztalon összeállított mérési elrendezésből egy komplett, automatikusan működő, terepen is használható mérőműszert fejlesztettünk. A műszert egy speciális földgázipari alkalmazáshoz optimalizáltuk; a földgázszárításban használt glikolban valamint a földgázban való mérésekre. Terepen is kipróbáltuk, a MOL egyik telephelyén. ABSTRACT We present here a measuring method which is combination of chromatography and photoacoustic spectroscopy. It can detect benzene and toluene concentration in gas and liquid samples over a wide dynamic range. The method was proved in ambient air and water samples. An automatic, field usable instrument was developed based on laboratory experiments. The instrument was optimized to a special application in gas industry. It can be applied to measure in natural gas and glycol used for dehydration of natural gas. Field measurements were carried out at a gas plant of MOL. BEVEZETÉS A benzol és a toluol az aromás szénhidrogének közé tartoznak. A környezetben leginkább szennyezőként fordulnak elő, főként antropogén forrásokból származnak. A benzol a különösen veszélyes, a toluol a mérsékelten veszélyes kategóriába sorolható egészségügyi szempontból. Akut mérgezés esetén mindkettő idegrendszer károsító hatású. A benzol emellett karcinogén is, ezért bármilyen kis mennyiségben is van jelen a környezetben, egészségügyi kockázatot jelent. Így tehát mennyiségük ismerete a környezeti levegőben vagy az ivóvízben fontos lehet. Benzolra határértékeket is állapítottak meg: ivóvízre 1 μg/l (201/2001 Kormányrendelet), míg a levegőre vonatkozó imissziós határértéke 5 μg/m3 (Európai Parlament és Tanács 2008/50/EK irányelve). A szabvány módszer a koncentrációk meghatározására a gázkromatográfia. A mérési eredmény egy hosszabb időperiódust jellemez,

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mivel a mintavételezés több órán át tart. Célszerű lenne egy olyan módszert találni, amellyel jobb időfelbontás érhető el. A földgáz és kőolajipar potenciális benzol és toluol emissziós források. Tipikus példa a földgázszárító telephelyek. A szárítás egyik lépése a glikolos érintkeztetés, amikor a nyers földgázból a vele érintkező (mono-, di- vagy trietilén) glikol kivonja a vizet. A glikolt ezután forralással regenerálják. A regenerálóból a víz gőz formájában távozik a páracsövön keresztül. A páracső végén az addig kondenzálódott vizet összegyűjtik, a maradék pedig a légkörbe távozik. A glikol azonban nem csak a vizet, hanem a szintén a nyers földgázban jelen lévő benzolt és toluolt is összegyűjti, és a forralás során nagy részük a légkörbe kerül, ami a telephelyen nagy imissziós értékeket okoz. A glikolregeneráló emissziója megadható, ha ismerjük a nyers és szárított gáz, valamint a híg (vizes) és tömény glikol benzol és toluol tartalmát, valamint az érintkeztetőn átáramló gáz mennyiségét. A cél tehát egy olyan műszer fejlesztése, amellyel gázban és glikolban is lehet benzol és toluol koncentrációt meghatározni automatikusan, terepi körülmények között. Itt is fontos, hogy ne egy hosszabb időintervallumra jellemző értéket kapjunk, hanem folyamatos, vagy legalábbis kvázifolyamatos legyen az adatszolgáltatás. A MÉRÉSI MÓDSZER A mérési módszer alapja a fotoakusztikus detektálás, amit adszorpciós mintavételezéssel és oszlopos elválasztással kombináltunk. A fotoakusztikus (FA) spektroszkópia alapjelensége az, hogy ha egy mintát akusztikus frekvencián modulált fénnyel megvilágítunk és a minta a fény egy részét elnyeli, akkor a minta a fény modulációs frekvenciájának megfelelő frekvenciájú hangot sugároz ki. Nagy előnye más spektroszkópiai módszerekkel szemben, hogy az elnyelt fénymennyiséget direkt módon méri és emiatt dinamikus tartománya jóval nagyobb, mint a többi módszeré. A FA rendszerek felépítése nagyon egyszerű. Szükséges hozzá egy mérőkamra, ami a megfelelő akusztikus szűrést elvégzi belső kialakításának köszönhetően. Kell egy fényforrás, ami jelen esetben egy 1669 nm központi hullámhosszú diódalézer. A keletkező hangot egy elektrét mikrofon detektálja. A lézervezérlést, jelfeldolgozást pedig egy Videotonnal közös fejlesztésű elektronikai egység végzi. A benzolnak és a toluolnak a közeli infravörös tartományban széles elnyelési sávja van, ezért a diódalézer keskeny hangolási tartományán (~2 nm) nem különböztethetők meg egymástól spektroszkópiailag. Szétválasztásukra egy kromatográfiás oszlopot alkalmaztunk. A pillanatszerű bejuttatást adszorberrel (Carbotrap) oldottuk meg, ami mintavételezést is végez. Az így összeállított mérési elrendezés gázfázisú mérésre alkalmas, ezért a folyadékmintákból kihajtással nyertük ki a mérendő komponenseket. Ivóvíz Az 1. ábrán a mérési elrendezés sematikus rajzát láthatjuk vízben való mérés esetén.

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tömegáramlásszabályozók

adszorber

kolonna FAkamra

víz

N2 keverés

1. ábra: Mérési elrendezés vízben való mérés esetén. Egy mérési ciklus két szakaszból állt. Az első szakaszban történt a kihajtás és az adszorpció. A másodikban az adszorbert felfűtöttük a köré tekert fűtőszál segítségével és a leadott molekulákat a nitrogén a kolonnán keresztül a fotoakusztikus kamrába juttatta. Eredményként egy kromatogramot kaptunk Különböző benzol és toluol tartalmú oldatokat mértünk meg. A vízminta 0,5 l térfogatú volt, ezen áramoltattunk át 0,25 l/perc-cel 5 percen át nitrogént. Környezeti levegő A környezeti levegőben való mérés hasonlóan történt, mint a vízben. Az első szakaszban egy membránpumpával adott mennyiségű levegőt szívtunk át az adszorberen, majd a kifűtési/jelfelvételi szakasz következett. Ekkor a labor levegőjében oszlattunk el benzolt és toluolt, és abból mintavételeztünk 1 l/perccel 20 percen át. Glikol és földgáz A vízben és környezeti levegőben való mérések tapasztalatai alapján a laboratóriumi asztalon összeállított mérési elrendezésből egy automatikusan működő, terepen is használható műszert építettünk. A műszer úgy optimalizáltuk, hogy a glikolregenerálók közegeiben (nyers, szárított földgáz; híg, tömény glikol) tudjon mérni, melyekben a benzol és toluol koncentráció nagyságrendekkel nagyobb koncentrációkban van jelen, mint környezeti levegőben vagy vízben. Éppen ezért a mintatérfogatot lecsökkentettük. Glikolból 1,5 ml-t, míg földgázból összesen 1 l-t mintavételezünk. Az ehhez szükséges idő mindkét esetben néhány perc. A kromatogram felvétele kb. 6,5 percig tart 10 ml/perc nitrogén áramlás mellett. Vagyis a mérési idő mindkét esetben kb. 10 perc. A műszert terepi körülmények között is kipróbáltuk a MOL egyik telephelyén. EREDMÉNYEK Víz A 2. ábrán vízben mért kromatogramokat láthatunk. Ilyen mintavételi paraméterek mellett kb. 3 μg/l a legkisebb kimutatható koncentráció (LKK), ami még az egészségügyi határérték felett van. A mintavételi tétfogat illetve idő növelésével LKK csökkenthető.

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2. ábra: Vízben mért kromatogramok. Környezeti levegő A 3. ábrán egy levegőben mért kromatogramot láthatunk. Ugyanazt állapíthatjuk meg, mint víz esetén, azaz az egészségügyi határérték fölött van a kimutatási határ ilyen mintavételezés mellett. A mintavételi idő megnövelésével LKK csökkenthető.

3. ábra: Levegőben mért kromatogram. Glikol és földgáz A földgázipar számára egy olyan műszert fejlesztettünk, amely automatikus, terepi mérésre alkalmas, és képes folyadék és gázminták analízisére is. A mintavételi egység megváltoztatása miatt a legkisebb kimutatható koncentrációk három nagyságrenddel megnőttek, viszont gázban akár 1-2 g/m3-es, folyadékban 500 mg/l-es koncentrációkat is meg tud mérni. A műszer folyadék és gázminták mérésére alkalmas, de egyszerre csak egyet képes mérni. Ez azt jelenti, hogy terepi körülmények között, minden közegről kb. óránként tud mérési adatot szolgáltatni.

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A 4. ábrán egy két hét hosszúságú terepi mérést láthatunk. A gáz, amiben mértünk, a glikolregeneráló fűtőgáza volt. Az ábrán a tömény glikolban mért gázkromatográfiás (GC) értékeket is feltüntettek, melyek jó egyezést mutatnak a FA mérésekkel.

4. ábra: Terepi mérés a MOL egyik telephelyén. ÖSSZEGZÉS A bemutatott mérési módszer alapja a fotoakusztikus detektálás, amit megfelelő mintavételezéssel és egy kromatográfiás oszloppal ötvöztünk. A mintavételezéstől függően gázokban a μg/m3 tartománytól egészen a g/m3 tartományig, folyadékokban néhány μg/ltől egészen 500 mg/l-ig tudtunk méréseket megvalósítani. A műszerré építéssel azt is bizonyítottuk, hogy a módszer nem csak laborban, hanem terepen is alkalmas mérések elvégzésére. KÖSZÖNETNYILVÁNÍTÁS A kutatást a MOL (UX 8307.11.53/95.) és a TÁMOP (4.2.1/B-09/1/KONV-2010-0005) támogatta.

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A VÁROSI BEÉPÍTETTSÉG HATÁSA A SZOLÁRIS RENDSZEREK MŰKÖDÉSÉRE: SZEGEDI VIZSGÁLATOK EREDMÉNYEI Hidvégi Henrik Szegedi Tudományegyetem Technika Tanszék Email: [email protected] ABSZTRAKT In the cities, where the only alternatives are the roofs for the solar utilization systems the orientation of these is very crucial. A wrong orientation will increase the size of the needed system and the area needs as well. In the following we will examine this issue in the case of an average electricity consuming household (at Szeged latitude). BEVEZETÉS Napenergia hasznosítás témájában fontos a tájolás és a dőlésszög kérdése. A hazai szakirodalomban szinte kizárólagosan a déli tájolás és a 45°-os dőlésszög értéke a preferált (30° és 60° mellett) [7] [8]. A tájolás függvényében a beesési szög éves alakulására végzett egyszerű modelljeink és egyéb tanulmányok [9] ennek az értéknek az egyeduralkodó létjogosultságát nem erősítették meg (1. diagram). Jelen tanulmányunkkal célunk volt annak vizsgálata (Szeged földrajzi helyzetére 1. diagram A beesési szögek 9:00 -15:00 átlagának éves vonatkozóan), hogy melyek lehetnek a változása eltérő dőlésszögek mellett (déli tájolás, Szeged) leginkább preferált tájolású felületek, mekkora sugárzási (és egyéb) energia bevétel1 érhető el általuk, és a sűrű városi felszínek kellő helyet nyújtanak-e egy átlagos rendszer számára. Felhasználva azokat a modelleket, adatokat és adatbázisokat melyek ehhez kellő alapul szolgálhatnak. ALAPOK A lakosság körében leginkább elterjedt napenergiát hasznosító berendezések a különböző napkollektorok és a (sík) fotovoltaikus napelemek. A különböző dőlésszögű és tájolású eszközök felületére érkező maximálisan kinyerhető napenergia2 mennyiségének meghatározásához szükséges a felületükre érkező globálsugárzás [1] ismerete. Szükség volt tehát olyan forrásokra melyek ezt teljesítik emellett pedig az energiatermelés karakterisztikája szempontjából fontos egyéb paramétereket3 is figyelembe veszik. Számításainknál a PV-GIS [11] (rögzített) fotovoltaikus rendszerekre vonatkozó adatait használtuk fel a kérdéskör vizsgálatára. Az itt kapott sugárzási eredmények szolgálnak alapul a későbbi becslésekhez. 1

A sugárzási információk forrásai alapvetően [2] a földi mérésekből, a műholdas adatokból és a numerikus időjárás-előrejelzési és éghajlati modellek újra elemzéséből származhatnak. 2 A sugárzáson túl egyéb meteorológiai tényezők (pl. hőmérséklet) is befolyásolják a hasznosítható napenergia mennyiséget [1]. A napelem villamos paraméterei a megvilágító fény spektrumától, intenzitásától és a napelem hőmérsékletétől is függenek. 3 A napelemek fő veszteségei: Ohmikus veszteségek (fém-félvezető átmenet, tömbi anyag, fémezés), optikai veszteségek (leárnyékolási, reflexiós, transzmissziós) [12].

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A napkövetés nélküli rendszerrel optimálisan elérhető sugárzási bevétel 1452 kWh/m2 a PV-GIS felülete alapján4 35° dőlésszög és D-i tájolás esetén. Érdekes megjegyezni, hogy amennyiben minden hónapban az adott déli irány mellett más dőlésszöget (2. diagram) állítanánk be, akkor sem jelentkezne jelentősen nagyobb sugárzási bevétel.

2. diagram Optimális sugárzás, optimális dőlésszög és egyéb dőlésszögek melletti havi sugárzási átlagok (Szeged, déli tájolás) Forrás: PV-GIS

Ezen kívül a nagyobb dőlésszög (60°) bár nagyobb bevételt jelent a téli félév során, de a nyert érték közel 4-szerese veszik el a nyári félév során (3. diagram). VIZSGÁLAT Összehasonlíthatóság és a gyakorlati hasznosság szempontjából azt vizsgáltuk meg, hogy az átlagos magyar háztartás által fogyasztott évi 2182 kWh áram [6], standard 3. diagram a téli és a nyári félév sugárzási bevétele különböző dőlésszögek mellett (Szeged, déli tájolás) Forrás: PV-GIS körülmények közepette mekkora és milyen tájolású felületről (tető, fal) fedezhető. A városokban a lapostető mellett (különösen a kertvárosi részekben) gyakori tetőtípusok (1. kép): sátortető

nyeregtető

kontytető

1. kép Jellemző tetőtípusok

Ezek jellemző dőlésszögeit a napenergia hasznosításban preferált 30°, 45° és 60° jól reprezentálja. A függőleges felületek mellett ilyen dőlésszögek és a 0°-os azimuth (dél) irányból kiindulva pozitív (NY) és negatív (K) irányban 30°-os lépésekben 12 égtájban kerültek vizsgálatra5. 4

A két választható sugárzási adatbázis adatai közül az ún. PVGIS-classic került felhasználásra, mivel ennek alacsonyabb értéke nem ad lehetőséget az értékek túlbecsülésére. A másik az ún. PVGIS-CMSAF adatbázisban a PVGIS-classic értékeitől évi 50-100 kWh/m2-el nagyobb értékek szerepelnek 5 Annak ellenére, hogy a teljesen K-i/NY-i vagy É-K-i/É-NY-i irányultságú felületeknél már minimális (pl. 10°os) dőlésnél is veszteséget jelent a vízszintes felültre jutó sugárzási bevételhez képest.

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A PV-GIS felületén a következő beállításokat alkalmaztuk: 1 kWp, kristályos szilícium 6 napelem , az alap 14%os rendszerveszteséget 10%-ra7 állítottuk be. A rendszer ezen beállításaival a fenti égtáj és dőlésszög bontásban kérdeztük le 4. diagram Napelemes rendszer felületigénye (déli tájolás) az adatokat. A modulok teljesítményre vonatkozó mérete befolyásolja a helyigényt. Itt három értéket vettünk figyelembe: 6, 7, 8 m2/kWp8. A legideálisabb esetben (30° ill. 35° déli tájolás, és a tetővel megegyező dőlés esetén) 11,38 m2 felület kell az átlagos igény fedezésére. Hasonló feltétel és 60°-os dőlés esetén sincs ettől jelentősebb felületigény9. A függőleges felületek (különösen az É-i) jelentik a másik végletet (5. diagram). Veszteségüket két 5. diagram Felületigény (függőleges felület, különböző tájolás és hatásfok) tényező okozza, az égbolt irányából érkező szórt sugárzás blokkolása illetve, hogy a nagy beesési szög a kis direkt sugárzási bevételt eredményező időszakban (elsősorban télen) jelentkezik. Az ideális esetnél 1,5-3-szor (É-i 6szor) nagyobb felület képes csak fedezni az igényt. A két szélsőséges érték közötti esetekre elmondható, hogy ekkora eltérések nem jelentkeznek. Az ideálishoz leginkább közelítő a déli iránytól 30°al eltérő esetekben mindössze 2%-11% között növekszik a felületigény. A 6. diagram Felületigény minimális és maximális %-os változása a déli iránytól való eltérés függvényében Dél-i iránytól 60°-al eltérve 6

Többi technológia 1 kWp-re nagyobb értéket ad, de kisebb hatásfokuk miatt nagyobb a helyigényük is. A jelenleg kapható jobb hatékonyságú inverterek kisebb veszteséget okoznak [10]. 8 Ettől eltérő helyigények is lehetnek a modulok mérete, kapcsolása és teljesítménye alapján. 9 Lapostető esetén a helyigény: felület * sin(90°-dőlészög), így pl. 60°- os dőlés esetén fele a fenti értéknek. 7

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9-22%-al változik. Míg a K-i és NY-i tájolás esetén már jelentős 21%-45% közötti a különbség a dőlésszögtől függően. 120°-al tehát ÉNY-i/ÉK-i irányban már 139-186 %-al is nagyobb terület beépítésére lehet szükség egy átlagos háztartás villamos igényének fedezésére. Az É-i illetve az É-i iránytól 30°-al eltérő felületek esetében a nagy (60°) dőlésű felületeken jelentkeznek csak igazán kiemelkedő, 2,5 – 3 –szoros értékek, tehát ennyiszer nagyobb, és közel ennyivel drágább rendszer beüzemelése szükséges ugyanazon igény kielégítésére. KÖVETKEZTETÉSEK A fotovoltaikus technológiák felületigénye (az átlagos áramfogyasztás igényeinek kielégítésére) ideális körülmények között nem jelentős. Egy átlagos családi vagy társasház tetőfelülete megfelelő az igények fedezésére. Azonban a tájolás függvényében akár jelentősen (2,5 -3-szor) is növekedhet a szükséges felület. Különösen a sűrűn lakott városi területeken ahol a tető kínálja az egyedüli alternatívát a rendszerek elhelyezésére, jelenthet ez problémát10. Egy rossz utcatájolás és egy ezt kihangsúlyozó egyeduralkodó tetőtípus jelentősen növelheti az igényeket. A nevesített 3 tetőtípus közül (a fentebbi megállapítások eredményeként) a nyeregtetős felületek kínálják a legkisebb alternatívát a rendszerek elhelyezésére, így ezek tájolására kiemelt figyelmet kell fordítani. A sátortető és kontytető esetén a legkedvezőtlenebb esetekben is legalább egy, de akár kettő tetőoldal is közel ideális irányultságú lehet. Könnyen és kis helyigénnyel biztosítva tehát a szükséges energia bevételt. IRODALOMJEGYZÉK [1]

Jethro Betcke: Mesor Training Seminar Part 1B: User needs – technical aspects, 2009

[2]

Elke Lorenz: Mesor Training Seminar Part 3: Overview on Solar Resource Products, 2009

[3]

Tom Stoffel et. al: Concentrating Solar Power - Best Practices Handbook for the Collection and Use of Solar Resource Data, Technical Report NREL/TP-550-47465, September 2010

[4]

Duffie and Beckman: Solar Engineering of Thermal Processes, 1991

[5]

Iqbal M.: Introduction to solar radiation. Academic Press Inc., 1984

[6]

A magyar villamosenergia-rendszer 2007.évi statisztikai adatai, 2007

[7]

Barótfi István: Energiafelhasználói kézikönyv. Budapest 1993

[8]

Dr. Gyurkovics Lajos: Hőtermelés napsugárból. Műszaki könyvkiadó, 1987

[9]

Marcel Suri et. al: Potential of solar electricity generation in the European Union member states and candidate countries. Solar Energy 81 (2007) 1295–1305

[10]

http://napelemek.blog.hu/2010/01/27/napelem_kalkulator

[11]

http://re.jrc.ec.europa.eu/pvgis/download/download.htm

[12]

http://kando.prociweb.hu/

10

A vizsgálat nem terjedt ki az eltérő tetőfelszínek kölcsönhatásából eredő veszteségekre.

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BIOSURFACTANT SYNTHESIS IN THE OIL EATER RHODOCOCCUS ERYTHROPOLIS MK1 STRAIN Krisztán Laczi, Á. Kis, K.L. Kovács, G. Rákhely and K. Perei Deparment of Biotechonology, University of Szeged, Közép fasor 52. H-6726 Szeged, Hungary Mail: [email protected] ABSTRACT Oil pollution is a very serious problem in the world. There were numerous oil spills in the last three decades and had great impact on the environment. They caused damages in wildlife as well as in economy by cutting down the agriculture, fishing, and tourism. Surfactants are useful weapons in the war against oil pollution. They are suitable to clean oil tanks and pipes and they are useful to solublize animal fats in food industrial wastewater. Many bacteria can produce substantial amount of biosurfactants which can emulsify hydrophobic hydrocarbons, so that the native microflora can utilize the pollutants. An additional advantage of the biosurfactants over the synthetic surface active molecules is that these compounds are easily biodegradable. A special biosurfactant group is composed of mycolic acids which are basically αalkyl, β-hydroxy fatty acids. Mycolic acids are the most characteristic components of the cell wall of the so called mycolata bacterial group. This group belongs to the Actinomycetales and contains the genera Mycobacterium, Corynebacterium, Nocardia, Rhodococcus and others. We aimed to map the mycolic acid biosynthesis pathway in Rhodococcus erythropolis MK1 strain isolated by us from polluted soil. In first step, we sequenced the genome of our strain by SOLIDTM next generation DNA sequencer. The reads were mapped on the R. erythropolis PR4 genome in the NCBI database. We searched for rhodococcal homologs of the known mycobacterial and corynebacterial genes involved in mycolic acid biosynthesis. We found conserved regions in the genome which are likely responsible for the biosynthesis of mycolic acids. The ongoing comparative whole genome transcript analysis will reveal the genes really necessary for the anabolism of mycolic acids. INTRUDUCTION Marine and terrestrial oil spills occurred all around the world in the last few decades. Oil has a great impact on wildlife. It covers animal’s skin, spreads on surface of the water obstructing it from the air. Crude oil contains many toxic compounds that are harmful for human and animal health and plants. Oil pollution influences plant life by inhibiting seed germination, reducing photosynthetic pigments, slowing down nutrient assimilation and shortening roots and other organs (S. Peng et al. 2009). There are many bacteria that could utilize some compounds of oil. However, the first big problem for them is the insolubility of oil in water. Some microorganisms synthesize surface active molecules so-called biosurfactants. These molecules lower the surface tension of the interface and emulsify oil enhancing its bioavailability for the cells. Biosurfactants can also enhance desorption of insoluble materials from surfaces. Bioemulsifiers have many advantages compared to the synthetic ones. For example they are biodegradable and

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consequently environmental friendly. These bioemulsifiers are suitable for many industrial purposes, such as bioremediation or solubilization of hydrophobic (waste) materials. It was shown, that addition of biosurfactants to the polluted soil or body of water could enhance utilization of oil compounds by the local bacterial flora. (E.Z. Ron. et al 2002). Biosurfactants with low critical micelle concentration and high degree of sorption to soil enhance soil washing efficiency (K. Urum et al 2004). One group of biosurfactants are mycolic acid (MA) containing products. Basically, MAs are α-alkyl, β-hydroxy fatty acids of variable chain length depending on the source. Mycolic acids are attached to the arabinogalactan cell wall or they can be found in free form as trehalose-dimycolates. The biosynthesis of mycolic acids is studied recently in Mycobacterium spp. (E. Raffidinarivo et al. 2009, S. Gavalda et al. 2009) and Corynebacterium spp.(R. Gande et al. 2004). Some key enzymes and reactions of the biosynthetic pathway of MA are known. The first key step is the synthesis of the C20 fatty acid catalyzed by an eukaryotic like fatty acid synthase I (FASI) enzyme. The C20 fatty acid chain is further elongated by the fatty acid synthase II (FASII) enzyme system which synthesizes the meroacyl chain. When the appropriate chain length was synthetyzed, the meroacyl chain is attached to a C22-26 fatty acid by Claisen type condensation. This synthesized MA is attached to a trehalose headgroup by a mycolil transferase and transported to the periplasmic space. In the periplasmic space further modifications are carried out by the periplasmic mycolil transferases (Takayama et al. 2005). The goal of this project is to map the mycolic acid biosynthesis pathway in Rhodococcus erythropolis MK1 strain. The R. erythropolis is gram positive, mesophilic, ubiquitous bacterium which can be found worldwide from deep seas to the mountains. The rhodococci are closely related to the genera Mycobacterium and Corynebacterium but not so pathogenic..This bacterium can grow on various hydrocarbons, emulsifying them with trehalo-mycolates. Our strain is able to grow on hexadecane, fuel/heavy oil, refuse oil and animal fat as carbon source. The cells form aggregates at the interface of water and organic phase with cell wall bound mycolic acids. The first step of this project was to sequence the genome of R. erythropolis MK1 with SOLIDTM next generation sequencer. MATERIALS AND METHODES Bacterium and growth conditions Rhodococcus erythropolis MK1: This strain was isolated by us from polluted soil. The culture was grown aerobically in 30 ml Luria-Bertani medium (5g yeast extract, 10g Trypton and 10g NaCl/L) at room temperature with shaking at160 rpm until OD600=0.7. Purification of genomic DNA Genomic DNA was purified from 30 ml of R. erythropolis MK1 strain cultured in LB medium by phenol-chloroform method as follows. After the culture reached OD600=0.7 1mg/mL Ampicillin was added to the culture medium. The culture was shaked at 160 rpm at room temperature for 2 hours. After incubation. the culture was centrifuged at 13,000 rpm, 4oC for 10 minutes. The pellet was resuspended in 5ml 100μg/mL lyzozime solution. The suspension was aliquoted by 1mL in five 1.5 mL centrifuge tubes and incubated for 2 hours on 37 oC. After incubation, the cells were collected by centrifugation at 13,000 rpm, 4oC for 10 minutes. The pellet was resuspended in 600μl Genomic I solution (10mM NaCl, 2mM Tris pH=8.0, 1mM EDTA and 0,5 w/v % SDS in each tube. 100 μg/ml proteinase K was added and the suspension was incubated on 50oC overnight. Then, it was phenol-chloroform (1:1) extracted The DNA was precipitataed by ethanol and air dried. The pellet was resuspenden in

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50 μl DNA grade water. The quantity and quality of DNA was checked spectroscopically and on 1% agarose gel. Whole genome sequencing The whole genome sequencing was carried out by SOLIDTM next generation DNA sequencer in the Bay Zoltán Foundation for Applied Research, Institute for Plant Genomics, Human Biotechnology and Bioenergy. The reads were mapped on the genome of R. erythropolis PR4 strain (AP008957) from the NCBI database. BLAST search We used NCBI BLAST (http://blast.ncbi.nlm.nih.gov/Blast.cgi) to identify homologues of mycobacterial and corynebacterial genes involved in mycolic acid synthesis. BLAST searches were carried out using the default options. RESULTS AND DISCUSSION During the next generation sequencing of the R erythropolis MK1 over 9 million reads were generated. The results of the mapping showed that the reads cover 97.4 % of the reference sequence (R. erythropolis PR4). According to the BLAST searches, there are some regions in the R erythropolis MK1 genome which are likely responsible for the biosynthesis of mycolic acids. The FasI system is responsible for the synthesis of C20-S-CoA and C22-26-S-CoA (Fig. 1). The Mycobacterial and Rhodococcal enzymes strongly resemble (∼ 75 % ) indicating similar biochemical reactions. Moreover, the mycobacterial genes of FASII system are 70-80% identical to the corresponding rhodococcal genes. However, there is one major difference in the two FASII systems. In the mycobacterial genome there are two type II β-ketoacyl-ACP synthases (kasA) and kasB) but in the rhodococcal genome we found only one (fabF⇔ kasA). (Fig.1) This fact can serve as an explanation for the shorter meroacyl chains in Rhodococcus. According to the literature kasB is responsible for further elongation of long meroacyl chains. Rhodococcal fabF is more similar to kasA which gene is responsible for elongation of the shorter meroacyl chains. The next key step of MA synthesis is the Claisen type condensation carried out by the polyketide synthase 13 (Pks13) and acetyl-CoA decarboxylases (AccDs). Two enzyme types are activating the two interacting molecules before the condensation. The FadD32 enzyme is a fatty acid AMP ligase that transfers the meroacyl chain from CoA to AMP. The other enzymes are AccD4 and AccD5 that carboxylate the C22-26-S-CoA at position 2. The pks13 gene of Rhodococcus erythropolis MK1 is 71% identical to the mycobacterial homologue. Similarly to the mycobacterial and corynebacterial gene organization, the R. erythropolis MK1 fadD32 gene is also adjacent to the pks13 gene which is followed by accD4 gene (Fig. 2). Moreover, two mycolil transferase genes can be seen downstream of the faD32 gene. These genes are fbpA and fbpD in M. tuberculosis and csp1 and RER02160 in R. erythropolis MK1.

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FasI

Acetate, malonate

C22-26-S-CoA Pks13,

Fas

Accd

Mycolic acids

Meroacyl-AMP

C20-S-CoA

InhA, Fad32 FabD

FabH KasA FabG1 Rhodococci KasB

Mycobacteria

FasII Figure.1 Mycolic acid biosynthesis pathway in mycobacteria and rhodococci The cps1 gene is likely homologue to fbpA and shows 50% similarity at amino acid level. The product of fbpA gene is the part of the so called antigen 85 complex, which is responsible for attaching two trehalose-monomycolates together or to the arabinogalactane cell wall in M. tuberculosis.

Figure 2. Genes involved in Claisen type condensation and mycolic acid processing (http:/www.ncbi.nlm.nih.gov)

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CONCLUSION Rhodococcus erythropolis is a useful tool for bioremediation of oil pollution and food industry waste waters. This organism synthesizes trehalomycolates, which are surface active agents of small molecular weight. These molecules are responsible for emulsification of oil and/or the cells can attach to the oil droplets via cell wall bound mycolates. According to BLAST results there are genes which are homologous to the known mycobacterial genes involved in MA synthesis. In addtion to the sequence resemblance, the genomic organization of the genes in these species are similar. We suggest that mycolic acid synthesis is carried out similar but not identical way as in Mycobacterium tuberculosi, which results in biosurfactant of special physicochemical properties.

REFERENCES R. Gande et al. (2004) Acyl-CoA carboxylases (accD2 and accD3), together with unique polyketide synthase (Cg-pks) are key to mycolic acid biosynthesis in Corinebacterianeae such as Corynebacterium glutamicum and Mycobacterium tuberculosis. The Journal of Biological Chemistry 279:44847-44857 S.Gavalda et al. (2009) The Pks13/FadD32 crosstalk for the biosynthesis of mycolic acids in Mycobacterium tuberculosis. Journal of Biologycal Chemistry 284:19255-19264 E. Raffidinarivo et al. (2009) Trafficking pathways of mycolic acids: structures, origin, mechanism of formation, and storage form of mycobacteric acids. Journal of lipid research 50:477-490 E.Z. Ron et al. (2002) Biosurfactants and oil bioremediation. Current Opinion in Biotechnology 13:249-252 K. Urum et al. (2004) Evaluation of biosurfactants for crude oil contaminated soil washing. Chemosphere 57:1139-1150 S. Peng et al. (2009) Phytoremediation of petroleum polluted soils by Mirabilis jalapa L. in a greenhouse plot experiment. Journal of Hazardous Materials 168:1490-1496 K. Takayama et al. (2005) Pathway to Synthesis and Processing of Mycolic Acids in Mycobacterium tuberculosis. Clinical Microbiology Reviews 18:81-101

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DENDROKRONOLÓGIAI VIZSGÁLATOK PINUS SYLVESTRIS FAFAJON – ESETTANULMÁNY A DUNA-TISZA KÖZÉN Ladányi Zsuzsanna, Blanka Viktória Szegedi Tudományegyetem, Természeti Földrajzi és Geoinformatikai Tanszék 6722 Szeged, Egyetem u. 2-6. e-mail: [email protected] ABSTRACT The aim of the study is to reveal the interrelation between the tree ring widths and the dominant climate parameters. The analysis was carried out on a climate sensitive microregion of the Danube-Tisza Interfluve, using pine (Pinus sylvestris) samples. On the basis of the investigations there is a significant correlation between the tree ring widths of the pine samples and the fluctuating climate parameters. The tree ring sensitivity of the analysed tree species verifies the considerable fluctuation of the dominant climate parameters (precipitation, temperature) in the region. The reasons of the high sensitivity are the highly permeable sandy soil, the significantly dropped groundwater level and the high drought sensitivity of the region. BEVEZETÉS Az elmúlt évtizedekben tapasztalható tájváltozások nyomán egyre fontosabbá vált annak ismerete, hogy mely tényezők és milyen mértékben befolyásolják a környezeti rendszerek működését (Kovács 2006, Rakonczai 2011). A klímaváltozás és az emberi hatások következményeképpen a Duna–Tisza közén kialakult talajvízszint-csökkenés okait és következményeit például az 1980-as évek óta számos tanulmány vizsgálta (Pálfai 1994, Pálfai 1995, Kuti 2002, Rakonczai 2011). A természetes és antropogén hatótényezőket az 1990-es években azonos mértékben tartották felelősnek a probléma kialakulásáért (Pálfai 1994), majd a 2000-es évek elején kiderült, hogy a hátság tetején a klímaváltozásnak köszönhető csapadékcsökkenés szerepe – mint természetes hatótényező – 80% (Völgyesi 2006, Szanyi-Kovács 2009). E tanulmány a klímaparaméterek és a hátság legmagasabban fekvő kistáj egyik legjellemzőbb, nem őshonos fafajának (erdei fenyő) évgyűrűszélessége közötti összefüggés vizsgálatát tűzte ki célul. MINTATERÜLET ÉS MÓDSZEREK A vizsgálatokat a Duna–Tisza köze egy klímaérzékeny kistáján az Illancson végeztük, mivel itt a vegetáció fejlődését a klímaparaméterek erősen befolyásolják. A mintaegyedek egy futóhomok-talajon telepített erdei fenyő erdőben kerültek kijelölésre (1. ábra), ügyelve arra, hogy a fafajok az uralkodó magassági osztályba tartozzanak, koronájuk és törzsük szabályos és egészséges legyen. Az erdei fenyő állományból 1,3 méter magasságból származó 4 fakorong képezte a mintát, melyen a 4 fő égtáj irányában végeztünk méréseket felületkezelés után Lintab 5 mérőasztalon TSAP-Win programmal. Az őszi és a tavaszi pászta, valamint a teljes évgyűrűszélesség is rögzítésre került. A klímaparaméterekkel való kapcsolat elemzéséhez a klimatikus körülményeket jól jellemző Pálfai-féle 1. ábra. A mintavétel helye aszályindex értékeket vettük figyelembe (Pálfai 2000). A fák évgyűrűinek vizsgálatánál tekintetbe kell venni, hogy a fák növekedésének kezdeti szakaszában az évgyűrűszélességek nagyok, majd az évek múlásával zavartalan környezeti

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tényezők mellett fokozatosan csökkennek (Alestalo 1971). Az évgyűrű-szélességekből ezért évgyűrű-indexet számoltunk, hogy kiküszöböljük a fák életkorából adódó torzítást. Így az évgyűrűszélesség és a környezeti tényezők (klíma) változása közötti kapcsolat jól vizsgálható. Az index a mért évgyűrűszélesség és az adatsorra illesztett exponenciális függvény megfelelő értékeinek hányadosa, mely azt fejezi ki, hogy az elméleti értékhez képest valójában annak hányad része realizálódott. Számítása: I=W/Y ahol I az évgyűrűindex értéke, W a mért évgyűrű-szélesség és Y az exponenciális függvény értéke az adott évre vonatkozóan (Frits 1976). Az évgyűrűindex számítása mellett kiszámításra került az évgyűrű-érzékenység is, amely kifejezi, hogy az egymást követő években a mért évgyűrű-szélességek mennyire változatosak, ami a környezeti tényezők ingadozását mutatja (Horváth 2003). Számítása: Si+1= ((xi+1-xi)*2)/(xi+1+xi) Átlagos évgyűrű-érzékenység: S=∑Si /(n-1) ahol xi az évgyűrűszélesség, n az évgyűrűk száma EREDMÉNYEK A négy égtáj irányában számított évgyűrű-indexek (2. ábra) átlagolásával megkaptuk a faegyedekre jellemző átlagos évgyűrű-index értékeket. Az évgyűrűszélesség és a klimatikus tényezők kapcsolatának vizsgálatához a továbbiakban ezeket az értékeket használtuk.

2. ábra. A 2. fakorongon mért évgyűrű-szélesség és a számított évgyűrűindex értékei Az évgyűrű szélessége sok tényező függvénye, melyet a néhány évtizedes periódusban állandónak tekinthető környezeti tényezők (például talajviszonyok, domborzat) mellett a meteorológiai és a hidrológiai tényezők ingadozása is erősen befolyásol. A rendkívül aszályos éveket keskeny évgyűrűszélességek jellemeznek, míg a csapadékos években szélesebb

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évgyűrűk jelentkeznek. Az évgyűrű-index értékeket összevetve a klimatikus körülményeket legjobban jellemző Pálfai index (PAI) értékeivel megállapítható, hogy a PAI alapján rendkívül aszályosnak jellemzett években (pl. 1993, 2003) az átlagostól lényegen keskenyebb évgyűrűk jelentkeztek, a legcsapadékosabb éveket (pl. 1999, 2005) pedig igen széles évgyűrűk jelzik, vagyis a két tényező között láthatóan kapcsolat van (3. ábra). A kapcsolat erősségének megállapításához végzett korrelációs számítás alapján a két tényező között 5%os szignifikanciaszinten egyértelmű a kapcsolat (R 0,34
3. ábra. A fakorongok átlagos évgyűrű-indexei és a Pálfai féle aszályossági index értékei a vizsgált időszakban Korreláció

1

2

3

4

1969-2008 (n=40)

0,34

0,41

0,35

0,38

1975-2008 (n=34)

0,37

0,58

0,52

0,41

1. táblázat. A fakorongok átlagos évgyűrű-indexei és a Pálfai-féle aszályossági index közötti kapcsolat erőssége Mivel az elemzések alapján a vizsgált fák érzékenyen reagálnak a meteorológiai tényezők éves változására, ezért a fákra ható klimatikus tényezők ingadozásának mértékét évgyűrűérzékenység alapján vizsgáltuk. Az évgyűrű érzékenység értéke azt mutatja, hogy milyen a vízellátottság mértéke a területen. Alacsony érték viszonylag állandó vízellátottságot jelez, az érték növekedése a vízellátottság korlátozottságára és ingadozására utal. Horvát (2003) érzékenységi kategóriái alapján a vizsgált fák értékei a közepes és a magas kategória határán mozognak (2. táblázat), melynek hátterében a térség jó vízáteresztő-képességű homoktalaja, a jelentősen lecsökkent talajvízszint, valamint a régió aszályérzékenysége áll.

Évgyűrű-érzékenység

1

2

3

4

0,27

0,25

0,28

0,38

2. táblázat. A fakorongok átlagos évgyűrű-érzékenysége (Átlagos érzékenységi osztályok: kicsi, ha S<=0,2; közepes, ha 0,2<=S<=0,3; nagy, ha S>=0,3)

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ÖSSZEFOGLALÁS A vizsgált fák évgyűrű-szélességek kapcsolatban áll a Pálfai-féle aszályossági index értékekkel. A korreláció szintje szignifikánsnak bizonyult (0,37
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HABITAT CHANGES OF AN ALKALINE LAKE, SOUTH HUNGARY Zsuzsanna Ladányi, János Rakonczai University of Szeged, Department of Physical Geography and Geoinformatics 6722 Szeged, Egyetem u. 2-6. e-mail: zsuzsi@geo.u-szeged.hu ABSTRACT In this paper a case study of a shallow alkaline lake located on the edge of the Danube-Tisza Interfluve is presented. Alkaline lakes are protected by the Act on Nature Conservation (No. LIII of 1996) in Hungary. Due to the anthropogenic activities (channelization) and the consequences of climate change (decreasing precipitation), the alteration of natural habitats of the sample area was identified. Soil investigations and vegetation mapping were made in order to demonstrate the noticeable changes and to supply data about the current conditions for further monitoring and management activities. The revealed degradation processes are relatively rapid and need urgent proper water-management. INTRODUCTION Alkaline lakes as wetlands with opened water-surface have an important role in preserving biodiversity. They are declared “ex lege” protected by the Act on Nature Conservation in 1996 in Hungary, since this type of wetland once so typical of the Carpathian Basin has drastically declined (Molnár 1996, Hoyk 2005, Bíró et al. 2007, Kovács 2009, Simon 2010 ). The special attention and protection are necessitated by their sensitivity and endangered status as well as the high number of protected and rare species they hold (Boros 2003). These natural lakes with high salt-content are characterized by significant water-level fluctuation. In the driest season lakebeds can completely dry out and the highly concentrated salt precipitates on the surface in the form of crystals. The accumulated salt on the surface was swept up and collected by local people and used for washing. Many of the plants are halophytes-plants that tolerate or even demand significant salt concentrations. Several factors has contributed to the decline of wetlands (inc. shallow saline lakes) in the Danube-Tisza Interfluve including natural threats such as the declining amount of precipitation due to climate change, and anthropogenic factors like drainage, landuse changes, river regulations, channelization, overexploitation of water resources etc. in the last decades. In this study, the alterations of an alkaline lake located on the edge of the Danube-Tisza Interfluve is investigated (Fig. 1.). MATERIALS and METHODS The sample area called Lake Kancsal was formed in a deflation hollow by the support of local and regional groundwaterwater-flow determined by high total salt content. The lakebed is around 16 hectare which has been water-covered till summer still in the 1970s. The lake was used for recreation and fishing purposes. The crossing channel was excavated in 1972. Soil attributes were measured at one sample point in the lakebed in 1949 (Kreybig 1949), and a short description of the vegetation was presented in 2007 about the lake (Tölgyesi – Ladányi 2007). A comparative study of our workgroup published its condition in 2009 among several wetlands in the DanubeTisza Interfluve (Barna et al. 2011). In order to describe the actual condition of the lake in 2011, habitat-mapping was made based on the categories of the General National Habitat Classification System (Bölöni et al. 2007) and the changes of the habitat-pattern were researched between 2002 and 2011. The species composition of habitats was also investigated. In case of the main habitat-types along a section, five soil

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parameters were measured based on the valid Hungarian standards (total salt content, alkalinity, calcium-content, phenolphthalein alkalinity /MSZ-08-0206-2:1978/, humus content / MSZ-2147052:1983/). By their detailed evaluation, the ongoing processes are aimed to be identified. During the data processing, ArcGis 9.3, Microsoft Excel and CorelDraw X3 were applied.

Fig. 1. The location and the DEM of the sample area (Lake Kancsal) RESULTS Vegetation A changing habitat pattern was observed in the lakebed (Fig. 2.) due to the lack of water-cover and the sinking groundwater-table as a result of the draining effect of the crossing channel and the decreasing precipitation related to climate change. At present in the lack of water retention in the channel, water is not retained in the lakebed even in spring period which would be needed by the characteristic alkaline vegetation.

Fig. 2. Habitat-changes of Lake Kancsal in the last decade (key according to A-NER) b1a: reed; b6: salt marsh; ba: channel; f2: salt meadow; f4: Puccinellia sward; f5: annual salt pioneer sward; h5b: closed sand steppe; p2c:Invasive schrub dominated stands; s7: Non-native tree species; u10: hamlet; u11: road. (transitional habitats indicated by „x”)

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An increasing extent of saline meadows along the channel could be identified (characteristic species are Agrostis stolonifera, Cirsium brachycephalum, Cynodon dactylon, Dactylis glomerata, Festuca pseudovina, Festuca arundinacea-pratensis, Lepidium crassifolium). Annual salt pioneer swards occur only in small extent (Lepidium crassifolium) and Puccinellia swards decrease significantly (Puccinellia limosa). Nevertheless, Puccinellia swards characterised by the highest naturalness have been still occurring in the largest extent showing near-surface salt accumulation in the lakebed. Due to the extreme precipitation in 2010, more transitional habitats formed (Fig. 2.) (transition of saline meadow/Puccinellia sward/salt marsh) showing the further leaching of salts in the area due to the channel without water-retention. Temporary water-covers showed the rise of groundwatertable in spring and early summer, proving that the extreme humid year would have helped the regeneration of the lake in case of water-retention. Soil The pattern observed in the case of the habitats is reflected by the attributes of the upper-soils (Fig. 3). Alkalinity, salt content and phenolphthalein alkalinity – according to the salt tolerance of habitats – show significant decrease towards the channel. Annual salt pioneer swards are determined by the highest salt content, alkalinity, phenolphthalein alkalinity and less humus content. Soil parameters of salt meadows are characterised by the least salt content, alkalinity and phenolphthalein alkalinity along the channel, which refers to the leaching of soils due to the draining effect of the channel. Their increased humus content refers to organic matter accumulation. The highest CaCO3 content can be observed in the upper 0-10 cm of the channel-bed contributing to its higher alkalinity.

Fig. 3/a. Soil sampling points in the lakebed

Fig.3/b. Measured parameters of upper soil in the main habitat-types CONCLUSIONS Based on the dynamics and the tendency of examined parameters drying, desalinization, leaching and humus accumulation processes could be identified (Fig. 4.). The draining effect of the channel is significant and indicated by the extending saline meadows. Although the alteration of soils is generally related to centuries, the rapid changes in hydrology can have effect on soils in decades. The vegetation proved to be a good indicator of the changes.

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Fig.4. Observed ongoing processes (altering alkaline landscapes) ACKNOWLEDGEMENT The Project was funded by „TÁMOP-4.2.1/B-09/1/KONV-2010-0005 – Creating the Center of Excellence at the University of Szeged”, supported by the European Union and co-financed by the European Regional Development Fund. REFERENCES Barna Gy. – Ladányi Zs. – Rakonczai J. - Deák J. Á. 2011: Változó alföldi táj: a talaj-víznövényzet kapcsolatrendszer vizsgálata különböző mintaterületeken. In Farsang A. – Ladányi Zs. (szerk.) Talajaink a változó természeti és társadalmi hatások között. Talajvédelem különszám, Talajvédelmi Alapítvány, pp. 117-126. Biró M. – Révész A. – Molnár Zs. – Horváth F. 2007: Regional habitat pattern of the DanubeTisza interfluve in Hungary I. The landscape structure and habitat pattern; the fen and alkali vegetation. Acta Bot. Hung., 49 (3-4), pp. 267–303. Boros E. 2003: Alkaline lakes. National Ecological Network 4. Authority for Nature Conservation, Ministry of Environment and Water, Budapest, 28 p. ISBN: 963 206 321 X Bölöni J. – Molnár Zs. – Kun A. – Biró M. 2007: Általános Nemzeti Élőhely-osztályozási Rendszer (Á–NÉR) (Hungarian National Habitat Classification System). Institute of Ecology and Botany, Hungarian Academy of Sciences, Vácrátót, 184 p. Hoyk E. 2005: A szárazodás hatása a vegetáció alakulására Homokhátsági szikes tavak példáján. In: Kiss A. – Mezősi G. – Sümeghy Z. (szerk.): Táj, környezet és társadalom. Ünnepi Tanulmányok Keveiné Bárány Ilona professzor asszony tiszteletére. pp. 293–303. Kovács F. 2009: Változékonyság értékelése vizes élőhelyeken műholdképek alapján. Hidrológiai Közlöny, 89 (2), pp. 57–61. Kreybig, l. 1943. Magyarország Átnézeti Talajismereti Térképe. Talajfelvételi jegyzőkönyv (5564/1 sz.) Magyar Királyi Földtani Intézet, Budapest. Molnár Zs. 1996: Vegetation history of the Kardoskút area (SE. Hungary) II.: The lake Fehértó in the last 200 years. Tiscia 30, 27-34. Simon Sz. 2010: Characterization of groundwater and lake interaction in saline environment, at Kelemenszék lake, Danube-Tisza Interfluve, Hungary. PhD Theses, Eötvös Loránd University, Budapest,167 p. Tölgyesi I. – Ladányi Zs. 2007: Tájváltozás értékelése Röszkén. In: Z. Galbács (ed) The 14th Symposium on Analytical and Environmental Problems, pp. 282-285. Tóth T. – Kuti L. – Fügedi U. 2003. Havonkénti vizsgálatok a Zabszék-mellett. A tóvíz, talajvíz, talaj, növényzet idobeli változásai. Természetvédelmi Közlemények, 10, pp. 191-206.

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BIODEGRADATION OF UNCTUOUS WASTES OF FOOD INDUSTRY Ágnes Kis1,2, K. Laczi1, R. Tengölics1, K.L. Kovács1,2, G. Rákhely1,2 and K. Perei1 1

Department of Biotechnology, University of Szeged, Közép fasor 52. H-6726 Szeged, Hungary 2 Institute of Biophysics, Biological Research Centre Hungarian Academy of Sciences, Temesvári krt. 62., H-6726 Szeged, Hungary mail: perei@brc.hu

ABSTRACT Nowadays, industrial emission of harmful materials is an extremely acute problem for humanity and Nature. Technologies with low or zero emission is of key importance to minimize the contamination of the ecosystem. However, vast amount of hazardous substances still gets out into the environment which must be made harmless. Bioremediation technologies using microorganisms to neutralize polluting materials are environmentally sound and economical tools for removal toxic compounds. It is a well-known fact that several Rhodococcus sp. can degrade a wide range of hazardous chemicals, such as aliphatic and aromatic hydrocarbons. In our laboratory, a Rhodococcus sp. was isolated from hydrocarbon polluted sites and it was successfully proven that the bacterium could efficiently degrade industrial hydrocarbons such as diesel oil and dead oil. The strain could tolerate low temperature and certain salt concentrations therefore it might be applied in oil mineralization after marine catastrophes. In this study, our aim was to test the ability of this strain to degrade food industrial and municipal waste. Lard, pig and poultry fat and cooking oil were used as sole carbon sources in minimal medium. The substrate utilization was demonstrated indirectly by measuring the respiration activity and CO2 production of the Rhodococcus sp. The strain could grow even at 10 g/l of hydrocarbon concentration, it consumed the available oxygen and released remarkable amount of carbon dioxide within a week. These facts make this strain a promising waste cleaner both in food industrial applications and housekeeping. 1. INTRODUCTION Nowadays, a major environmental problem is the emission of hazardous materials by industry, agriculture and other human activities. It is very hard to neutralize various oils and their derivatives (n-alkanes, aliphatic-, aromatic hydrocarbons) because of their physicochemical properties. Fortunately, there are „oil eater” microbes capable for decomposition and assimilation of many type of hydrocarbons [1]. The bioremediation of diesel oil is a relatively simple process, because it contains mainly linear alkanes. During aerob biodegradation, microorganisms such as Rhodococcus sp. [2] and Pseudomonas sp. oxidize these compounds with their monooxygenases which is followed by a successive biochemical reaction set completing the degradation. These microorganisms improve the bioavailability of such hydrophobic compounds by their surfactants [2, 3].

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A Rhodococcus sp. was isolated from a hydrocarbon polluted site. This strain was able to grow on diesel and dead oil as carbon sources in laboratory conditions. However, in addition to crude oil and its derivatives, it is also important to neutralize food industrial and municipal unctuous wastes in an environmentally sound way. Thus, the goal of this project was to establish whether the strain could utilize organic carbons, such as pig-, poultry fat, lard and cooking oil, as sole carbon sources. The biodegradation processes were followed by measuring the respiration activity and CO2 emission of the cells. 2. MATERIALS AND METHODS 2.1. Microorganism Rhodococcus sp. was isolated by us from hydrocarbon polluted site at Mohács, Hungary. 2.2. Materials used Carbon sources: pig-, poultry fat, lard, cooking oil, diesel and dead oil were sterilized at 100 °C for 1 hour before . Luria-Bertani medium (LB): 1L medium contains 5g yeast extract, 10g Trypton and 10g NaCl (20 g/L agar for agar plates) Minimal salt medium (MSM) containing 0,68 g/l KH2PO4, 0,87 g/L K2HPO4, 0,58 g/L NaCl, 0,125 g/L MgSO4 x 7H2O, 0,044 g/L CaCl2 x 2H2O, 0,0012 g/L NH4NO3, 0,014 g/L FeSO4 comlexed with EDTA, 2 ml of trace element solution (pH=6,8). Trace element solution: 0,1g/L ZnSO4 x 7H2O, 0,03g/L MnCl2 x 7H2O, 0,3g/L H3BO4, 0,2g/L CoCl2 x 6H2O, 0,01g/L CuCl2 x 2H2O, 0,02g/L NiCl2 x 6H2O, 0,03g/L NaMoO4 x 6H2O 2.3. Bacterial growth conditions Starter culture was grown in LB, the cells were collected by centrifugation then suspended in 25 ml MSM containing 1% (v/v) of the carbon sources. The flasks were shaked at150 rpm at room temperature. The control flasks did not contain cells. 2.4. Gas Chromatography (GC) The oxygen content of the headspace was measured by Agilent 6890 gas chromatograph, equipped with a thermal conductivity detector (TCD) and a HP-MOLESIEVE column (30m x 0,53mm i.d. x 0,25μm). The injector was kept at 150 °C while the oven temperature was adjusted to 60 °C. The injector was in splitless mode and nitrogen was used as carrier gas. For the carbon dioxide measurements, Shimadzu 2010 gas chromatograph was used, equipped with a TCD and HP-PlotQ column (30m x 0,53 i.d. x 0,25μm). The temperature of the injector and oven was 200 °C and 90 °C, respectively. Samples of 50μl were injected via a split injection port at a split ratio of 0,5:1. Carrier gas was nitrogen at a flow rate of 63.8 mL/min.

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3. RESULTS 3.1. Rhodococcus sp. consumes both diesel and dead oil During aerobic biodegradation, the cells use O2 for oxidation of the substrates and mainly biomass and CO2 will be formed. Therefore, following the respiratory activity and CO2 production of cells growing on unctuous substrates as sole carbon source are good tools to monitor the cellular activities, the bioremediation processes. The diesel and dead oil were utilized by Rhodococcus sp. as sole carbon sources with different efficiencies. The cells were grown on diesel oil consumed all oxygen till the 7. day, however, cells cultivated on dead oil used only about 50% of the available oxygen (Fig. 1). Carbon dioxide production was also 50% larger within this period for samples using diesel oil as compared to those propagated on dead oil (Fig. 1). 25

12 10

20

6 10

CO2 (ml)

O2 (ml)

8 15

4 5

2

0

0 0

1

3

6

7

Time (days) Diesel oil O2

Dead oil O2

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Fig 1. Respiration activity and CO2 production of Rhodococcus sp. grown on diesel oil and dead oil as carbon sources 3.2. Our isolate could efficiently utilize pig-, poultry fat, lard and cooking oil The bacterium could also decompose both leaf-lard and lard carbon sources, but the efficiencies were slightly varied with the substrates (Fig. 2). Cell respiration was more intense on leaf-lard than on lard. When leaf-lard was the sole carbon source the cells consumed all of the available oxygen in 3 days, while in the case of lard, residual some oxygen could be detected after 7 days. Analyzing the CO2 production led to similar conclusions. Cells grown on leaf-lard released more CO2 within shorter time as compared to the lard grown samples. It is remarkable that - although no serious differences could be observed in oxygen consumption during growth on leaf-lard, poultry fat or grease - the carbon dioxide emission was significantly less in the cultures cultivated on poultry relative to the other samples (Fig. 2). The cooking oil is also an unctuous substrate of special physical and chemical properties. However, our Rhodococcus strain was able to grow well on cooking oil, as well. The cells

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could be adopted rapidly to cooking oil floating on water surface. This degradation of the substrate was clearly confirmed by the persistent decreasing of the oxygen concentration and carbon dioxide release into the headspace of samples. Oxygen was completely taken up after 5-6 days and – accordingly – most of the CO2 was produced till the 6th day (data not shown). 25

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Fig. 2. Oxygen demand and CO2 production of Rhodococcus sp. grown on leaf-lard, lard, poultry fat and grease. CONCLUSION ¾ Our Rhodococcus sp. isolate could be easily adopted to the unctuous carbon sources studied. ¾ In addition to diesel oil and its derivatives, this strain could efficiently decompose leaf-lard, poultry grease, lard, poultry fat and cooking oil as single carbon and energy source. ¾ Our microbe is a truly promising waste cleaner both in environmental, food industrial applications and in housekeeping. REFERENCES 1. Atlas R.M. (1981). Bioremediation of petroleum hydrocarbons, Microbiology Reviews 45: 180-209 2. Bell K.S., J.C. Philp, D.W.J. Aw and N. Christofi (1998). The genus Rhodococcus, Journal of Applied Microbiology 85: 195-210 3. Carvalho C.C.C.R. de, L.Y. Wick, H.J. Heipieper (2009). Cell wall adaptations of planktonic and biofilm Rhodococcus erythropolis cells to growth on C5 to C16 n-alkane hydrocarbons, Applied Microbiology and Biotechnology, 82: 311–320.

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AZ OPTIMÁLIS KÖRNYEZETI MAGNÉZIUM ELLÁTOTTSÁG DAGANATELLENES HATÁSA Kiss Zoltán*, Ácsné Kecskeméti Beáta+ Dr. Diósszilágyi Sámuel Kórház-Rendelőintézet Belgyógyászati Osztály* és Központi Klinikai Laboratórium+ H-6900 Makó, Kórház u. 2. Pf.: 72. e-mail: kiss.zoltan@dioshosp.hu BEVEZETÉS A rosszindulatú daganatos betegségek Magyarországon és szerte Európában is komoly népegészségügyi gondot jelentenek (1). 2007-ben a KSH adatai szerint hazánkban összesen 132.938 fő (68.241 férfi és 64.697 nő) halt meg. Rosszindulatú daganatos betegségben 31.686 fő (17.760 férfi és 13.926 nő, az összhalálozás 23,83%-a) hunyt el. A 2005-öt megelőző évek halálozási arányának csökkenése csak látszólagos, statisztikai módszertani változások okozzák. A szakirodalom és saját közvetett adataink egyértelműen utalnak a környezeti magnézium ellátottság rákellenes, gyulladásellenes (2) és antiproliferatív, sejtosztódást gátló hatásaira (3, 4). Az L-typusú Ca-csatornákban MgSO4 gátolja az endotoxin- vagy egyéb úton indukált, a népbetegségek (magas vérnyomás, cukorbetegség, daganatok) kialakulásában szerepet játszó inflammatorikus molekulák (macrophage inflammatory protein-2, tumour necrosis factor-α, Interleukin (IL)-Iβ, IL-6, nitric oxide/inducible nitric oxide synthase, prostaglandin E2/cyclo-oxygenase-2) felszaporodását, az NFκB aktivitás-növekedést és DNSkötődést egér makrofágokban. Ezt a hatást Ca vagy az L-típusú Ca-csatorna aktivátor BAYK8644 visszafordította. Epidemiológiai tanulmányok a rák incidencia szignifikáns csökkenését mutatják magas magnéziumtartalmú diéta, ill. extra magnéziumpótlás hatására (5). Minden daganatgátló lehetőség tárgyalása fontos, hiszen jelenleg számtalan lehetőségünk (citosztatikumok, tirozin-kináz-, neovascularisatio-gátlás, aminosav-depriváció, vaccina, nanomedicina) ellenére ideális rákellenes szerünk nincs. Vannak arra is adatok, hogy keringő emlőrák-sejtek 7-22 évvel a mastectomia, klinikai gyógyulás után is kimutathatók (6). BETEGANYAG ÉS MÓDSZER Anyagunkat a környezeti magnézium ellátottság, a C-reaktív protein és a daganatos betegségek összefüggése vonatkozásában korábban már ismertettük (7). A környezeti magnézium ellátottság fogalmát abban az értelemben használjuk, hogy a belgyógyászati szakrendelésre vagy osztályra beérkező betegek vérmintáit még a különböző kiegészítő, vagy módosító kezelések megkezdése előtt levettük, ill. meghatároztuk. Optimális magnézium ellátottságról a szakirodalommal egyetértésben 0,9 mmol/l serum magnézium-szint (se Mg) felett beszélünk. Laboratóriumilag természetesen a se Mg-szint 0,75 mmol/l felett normálisnak tekinthető és az is bizonyos, hogy a se Mg és ezen belül az ionizált magnézium (Mg++)-szint sem pontos tükre a Mg-homeostasisnak (8), de csökkenése vagy emelkedése elfogadott paraméter a klinikai tanulmányokban. Nem nyújtott többet a vvt és lymphocyta Mg-tartalom meghatározása és egyéb módszerek sem. A se Mg-szinteket kolorimetriás, xilidilkék-komplex módszerrel határoztuk meg Bayer ADVIA 1650 kémiai automatával. 108 máj-, tüdő-, colorectalis-, emlő-, gastrooesophagealis-, hasnyálmirigy-, prostatarákos, acut myeloid leukaemiában szenvedő betegből csak 29-nek volt a se Mg-szintje az optimális

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érték felett. Egyiküknek sem volt az értéke 1,15 mmol/l, a felső se Mg határérték felett. Ezekkel az arányokkal összecseng az 5469 véletlenszerűen választott, mindkét nemű magyar népesség se Mg szűrővizsgálata, mely szerint a se Mg-szint csak 6,55%-ban volt optimális, 1,08%-ban volt 1 mmol/l felett, a fennmaradó 92,37%-ban a kívánatos alatt volt. Kétségtelen, hogy összefüggés van a daganatsejtek kemoterápia okozta szétesése és a Mgszintek között. Megfigyelték (9), hogy kemoterápia idején a vizelet Mg és Ca kiválasztása nő. Irradiatio kapcsán azt találták, hogy a vizelet Mg-kiválasztás növekedése 50%-kal is növekszik a tumormassza becsült felére csökkenésekor. A közben mért serum bikarbonátszint ugyan csökkent, de a normál tartományban maradt és nagy valószínűséggel a fokozott vizelet Mg- és Ca-kiválasztás okozta (10). Túlsúlyos betegekben a folyékony protein-zsír diéta idején úgyszintén kisfokú serum bikarbonát-szint változást tapasztaltak az előbb jelzett ok miatt (11). A cukorbetegekben gyakoribb daganatelőfordulás oka lehet, hogy a human insulin-receptor praecursor sequentia nagy hasonlóságot mutat a tirozin-kináz csoportba tartozó src-onkogénnel (12). EXPERIMENTALIS ÉS KLINIKAI TANULMÁNYOK A már idézett hazai felmérés szerint feltételezhető, hogy a serum és a következményes interstitialis-intracellularis Mg-szint fiziológiást meghaladó értéke (1-, 0,4-0,6 mmol/l) megállíthatja a ráksejtek patológiás szaporodását azáltal, hogy a megváltozott mikrokörnyezet (13) programozott sejthalált indukál (14, 15). Emberi kromatinhoz kötött Ca++/Mg++dependens endonuclease a chromaffin internucleosomalis DNS széttöredezését okozza emberi emlőcarcinoma MCF7 sejttenyészetben. Ezt az endonuclease-t apoptoticus nuclease-nak is hívják, mivel ez a localisatio egyedülálló jelenség (16). A legtöbb rákellenes gyógyszer, mint pl. az etoposide, methotrexate, cisplatin, chlorambucil, 5-FdUrd és a radioterápia apoptosist képes indukálni a daganatsejtekben in vivo és in vitro egyaránt. Az apoptosist közvetítő caspase-3 túlzott aktivitása a phospholipase-A2 révén azonban a sugárkezelést, kemoterápiát túlélő ráksejtek szaporodását növelő arachidonsav és prostaglandin E2 felszabaduláshoz vezet (17). Az optimális Mg ellátottság-szint előnye, hogy – ellentétben a nanorészecskékbe csomagolt gyógyszerekkel – nem igényel felszívódásfokozó adjuvánst és mint a természet élettani Ca-csatorna blockolója az emberi szervezetben aktiválva vagy módosítva mintegy 350 enzimfolyamatot és sejthártya-csatornát az intracellularis koncentrációja változásával (0,4-0,6-tól > 6,5 mmol/l) képes az ún. nyugvó, a filogenesis során korábban aktív daganatellenes enzimfolyamatok reaktiválására (18), amelyek tumor-suppressorként hatnak, genome stabilizátorok. Megjegyzendő még, hogy a Mg-nak subcellularis hatásai mellett magasabb intracellularis koncentrációban farmakológiai hatása is van. Biztonságos és nem költséges kezelési mód. Hatását az újabb ismeretek szerint az ún. transiens receptor potential csatornák (TRPM6 és 7, melastatin alcsoport) növelik és közvetítik. A TRPM7 a tulajdonképpeni Mg-csatorna, a Mg homeostasis biztosítása mellett kifejezett szerepe van a sejtproliferációban és a programozott sejthalálban a leggyakoribb emberi rosszindulatú daganatokban. Egyébként a csatorna Ca-aktivált, kevéssé feszültségfüggő, aspecifikus környezeti csatorna (14, 15), amely jelen van az emberi test szinte mindegyik szövetében és sejttípusában. Sokféle, fizikai, kémiai, humoralis tényező és jelközvetítő molekula játszik szerepet pl. a környezeti mérgek okozta carcinogenesisben, így érthető ezeknek a csatornáknak a jelentősége. Emellett a daganatsejtek képződésének gátlásában az aquaporin1-nek (AQP-1) is szerepe van. Kiderült, hogy deletio miatt egérben csökken a neoangiogenesis (19), túlsúlya fokozza az endothel és egyéb sejtmigratiot (aquaporin-4) pl. embrióban (20). Oestrogenhatásra (21) a VEGF expressioját növeli.

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KÖVETKEZTÉSEK Szakirodalmi adatok és korábbi közlésünk (22) is arra utal, hogy a se Mg-szint és ennek következtében az interstitium és a citosol Mg-szintjének megváltoztatására-emelésére van terápiás lehetőség és ez az antiproliferatív, daganatos sejtosztódást mérsékli, a programozott sejthalált fokozza (2). Androgén-hormon-dependens prostatarákban a TRPM7 túlreprezentált, a daganat előrehaladásával, kiterjedtebbé válásával pedig alig mutatható ki (23, 24). Élettani körülmények között az extracellularis Mg a Ca-mal szinergizmusban aktiválja a T-sejteket (25), a mitogeneket (26) a B-sejteket azonban nem. A Mg-hiány rendkívül disruptiv az embriogenesisre és a thymopoesisre egyaránt (27). A Mg-hiány hypoxiában gátolja az erythropoetin és VEGF-képződést, a sejtadhaesiot és az apoptosist, elindítva ezzel a carcinogenesist (28). A Mg daganatellenes hatásának alapja az is, hogy a gyorsan osztódó daganatsejtekben a citosol Na+-Cl--tartalom nő, a Mg++-K+-tartalom csökken még a gyorsan osztódó normális sejtekhez képest is. A folyamat megfordítása daganatgátló hatású (29). Kissejtes tüdőrákban és prostatarákban a feszültségfüggő, excitabilis szövetekre jellemző Na+- (30, 31), még méhnyakrák-sejttenyészetben a volumen-szenzitív Cl--csatornák mutathatók ki nagy sűrűségben (32). A cAMP által szabályozott Cl- csatornákat K562 emberi myeloid sejtvonal sejtjeiben Mg++ gátolja, befolyásolva a sejtproliferatiot (33). A Mg-influx mint jelközvetítő („second messenger”) csökkenése T-sejt immundeficienciához, közvetve a T-sejt specifikus immunmoduláció megváltoztatásával a rosszindulatú daganatok szaporodásához vezet (34). Ismert, hogy túlzott T-sejt aktiváció, a citosol Mg++-koncentráció emelkedése viszont autoimmun kórképeket (diabetes mellitus, SLE, RA, szervtranszplantátum kilökődés) okoz a fokozott Mg-transporter-1 (MAGT1) aktivitás miatt (35). Szerencsére a Mg-szint emelkedés okozta visszacsatolási mechanizmus ezt megakadályozza. Az angiotensin-II szerepe is felmerül, mivel az angiotensin-receptor-1 és 2-nek (ATR1, 2) szerepe van a proinflammatorikus mediatorok szintézisében az erekben és a gyulladásos sejtekben egyaránt. A tumort körülvevő makrofagokban is fokozott az ATRa-expressziója és a VEGF képződése (36). Az ACE-inhibitorok és angiotensin-receptorgátlók antiproliferatív, neoangiogenesis, gyulladás és szöveti remodelling gátló hatásúak (37, 38). Egyébként a daganaterek változó lumenű és alakú, hiányos érbelhártya és pericyta borítású, fokozott permeabilitású sejtek (39). A permeabilitás oestrogen-hatásra fokozódik, még tovább könnyítve a citosztatikumok bejutását a daganatsejtekbe (21). Az ATR1 a leukocyta extravasatiot az endothel és vascularis adhaesios molekulák (E- és P-selectin, ill. vascular cell adhesion molecule, VCAM-1) upregulatioját okozza. A VCAM-1 szintézist az endothelben a H2O2 és NFκB indukálja (40), a fibroblastokban az NFκB, AP-1 és a PKC aktiválta VEGF. Gátlásuk Mg-mal rákellenes, metastasist akadályozó hatású lehet (41). Az ATR2 receptor értágító (42) és érképződés-gátló (43) hatása megmarad. Végül, de nem utolsó sorban fontos hangsúlyozni, hogy az alacsony és a magas Mg-szintek ugyan egyaránt gátolják a sejtosztódást éppen úgy, mint a deutériumtartalom hasonló változás, de az alacsony Mg-szintek hátrányos hatásai miatt az intracellularis miliő megváltoztatására a Mg-pótlás célszerű. Természetesen a Mg mellett a kiegyensúlyozott nyomelemellátás is fontos a genome integráció megőrzése céljából (44). A redox homeostasis vonatkozásában Szentmihályi Klára és mtsai munkájára utalunk (45).

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ÖSSZEFOGLALÁS A szerzők összefoglalják a magnézium különböző rosszindulatú daganatokra kifejtett antiproliferatív hatására vonatkozó szakirodalmi és saját adataikat. Epidemiológiai tanulmányok diétás és/vagy extra magnéziumpótlás eredményeként a rákhalálozás szignifikáns csökkenését bizonyították. Saját anyagukban 108 máj-, tüdő-, vastag-végbél-, emlő-, gyomor-, bélrendszeri-, prostata- és hasnyálmirigyrákban, ill. heveny fehérvérűségben szenvedő betegből csak 29-nek volt a serum magnézium szintje az optimálisnak tekintett 0,9 mmol/l felett és egyiküknek sem volt 1,15 mmol/l, az élettani felső határ felett. 5469 személyben végzett hazai szűrővizsgálat szerint a serum magnézium szint csak 1,08%-ban volt 1 mmol/l felett. 6,55%-ban optimális, a fennmaradó 92,37%-ban pedig a kívánatos alatt volt a serum magnézium-szint. Ezek alapján adódhat a feltételezés, hogy a serum és a következményes interstitialis-intracellularis Mg++ szint emelése a normális (1-, 0,4-0,6 mmol/l) fölé megállíthatja a kóros ráksejt proliferatiot a daganat mikrokörnyezetének megváltoztatásával és programozott sejthalált indukálhat. Magnéziumot tartalmazó nanoparticulák felszívódásához felszívódást fokozó adjuváns is szükséges, míg a Mg önmagában mint a természet élettani Ca-csatorna blockolója az emberi szervezetben befolyásol és módosít számtalan enzimfolyamatot és sejtfalcsatornát a külső hatásokra rendkívül változékony intracellularis koncentráció változtatása (0,4-0,6 mmol/l-tól >6,5 mmol/l-ig) révén. A Mg-adagolás biztonságos és nem költséges a kóros sejtproliferatio mérséklésére. SUMMARY The author summarizes the literature data of magnesium (Mg) effect on different cancers based on its antiproliferative properties supported by indirect own data. Epidemiologic studies show a significant decrease of cancer mortality due to dietary and/or extra Mg supplementation. Own data demonstrate that in 108 cases of hepatic, lung, colorectal, mammary, gastroesophageal, prostate, pancreas cancer, acute myeloid leukaemia, only 29 patients’ serum Mg level was above the „optimal” value, such as 0.9 mm/L. None of them had serum Mg level above 1.15 mm/L. In selected Hungarian population (5469 persons), serum Mg level was in 1.08 percent above 1.00 mm/L, while in 6,55% was optimal, in 92,37% was under the desirable level. One could hypothesize that elevation of serum and consequently interstitial-intracellular Mg++ level above the normal (1-, 0.4-0.6 mm/L, respectively), may stop pathologic proliferation of cancer cells via dissecting of tumour microenvironment and could induce programmed cell death in them. Mg encapsulating nanoparticles, permeation enhancers to intestinal mucosa are not necessary to the effect of Mg as a nature’s physiologic calcium channel blocker in human body affecting and modulating many enzym processes and cell membrane channels due to its highly variable intracellular concentration (from 0.4-0.6 mm/L to >6.5 mm/L). It’s safe and inexpensive treatment against pathologic cell proliferation.

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IRODALOM 1. Boncz, I., Sebestyen, A.: Economy and mortality in Eastern and Western Europe between 19451990: the largest medical trial of history. Int. J. Epidemiol. 35, 796-797, 2006. 2. Lin, C. Y., Tsai, P.S., Hung, Y.C., Huang, C. J.: L-type calcium channels ar involved in mediating the anti-inflammatory effects of magnesium sulphate. Br. J. Anaesth. 104, 44-51, 2010. 3. Hartwig, A.: Role of magnesium in genomic stability. Mutat. Res. 475, 113-121, 2001. 4. Mori, H., Morishita, Y., Shinoda, T., Tanaka, T.: Preventive effect of magnesium hydroxide on carcinogen-induced large bowel carcinogenesis in rats. Basic Life Sci. 61, 111-118, 1993. 5. Larsson, S.C., Bergkvist, L., Wolk, A.: Magnesium intake in relation to risk of colorectal cancer in women. JAMA 293, 86-89, 2005. 6. Uhr, J., Pantel, K.: Controversies in clinical cancer dormancy. PNAS 108, 12396-12400, 2011. 7. Kiss, Z., Ácsné, K.B.: A környezeti magnézium ellátottság, a C-reaktív protein és a daganatos betegségek összefüggése. Proc. 16th Symposium in Analytical and Environmental Problems. (Ed. Z. Galbács) pp. 424-429, Szeged, 28 September 2009. 8. Foley, C., Zaritsky, A.: Should we measure ionized magnesium? Crit. Care Med. 26, 1949-1950, 1998. 9. Araszkiewicz, Z., Derentowicz, P., Pirozynski, M., Radomyski, A.: Effect of vincristine, adriamycine and cyclophosphamide on selected indices of magnesium metabolism. Magnes. Bull. 9, 40, 1987. 10. Licata, A.A., Bou, E., Bartter, F.C., Cox, J.: Effect of dietary protein on urinary calcium in normal subjects and in patients with nephrolithiasis. Metabolism 28, 895, 1979. 11. Licata, A.A., Antigua, R., Amatruda, J., Lockwood, D.: Adverse effects of liquid protein fast on the handling of magnesium, calcium and phosphorus. Am. J. Med. 71, 767, 1981. 12. Ullrich, A., Bell, J.R., Chen, E.Y. et al.: Human insulin receptor and its relationship to the tyrosine kinase family of oncogenes. Nature 313, 756-761, 1985. 13. Anderson, A.R. et al.: Tumor morphology and phenotypic evolution driven by selective pressure from the microenvironment. Cell 127, 905-915, 2006. 14. Abed, E., Moreau, R.: Importance of melastatin-like transient receptor potential 7 and cations (magnesium, calcium) in human osteoblast-like cell proliferation. Cell. Prolif. 40, 849-865, 2007. 15. Jiang, J., Li, M.H., Inoue, K., Chu, X.P., Seeds, J., Xiong, Z.G.: Transient receptor potential melastatin 7-like current in human head and neck carcinoma cells: role in cell proliferation. Cancer Res. 67, 10929-10938, 2007. 16. Sokolova,I.A., Cowan, K.H., Schneider, E.: Ca++/Mg++-dependent endonuclease activation is an early event in VP-16-induced apoptosis of human breast cancer MCF7 cells in vitro. Biochim. Biophys. Acta 1266, 135-142, 1995. 17. Connell, P.P., Weichselbaum, R.R.: A downside to apoptosis in cancer therapy? Nature Med. 17, 780-782, 2011. 18. Blow, J.J., Ge, X.Q., Jackson, D.A.: How dormant origins promote complete genome replication. Tr. Biochem. Sci. 36, 405-414, 2011. 19. Saadoun, S. et al.: Impairment of angiogenesis and cell migration by targeted aquaporin-1 gene disruption. Nature 434, 786-792, 2005. 20. Verkman, A.S.: Aquaporin water channels and endothelial cell function. J. Anat. 200, 617-627, 2002. 21. Richard, C. et al.: Aquaporin water channel genes are differentially expressed and regulated by ovarian steroids during the periimplantation period in the mouse. Endocrinology 144, 1533-1541, 2003. 22. Kiss, Z.: Evidences of magnesium effect in clinical practice: metaanalyses and randomized clinical trials. Magn. Res. 16, 331, 2003. 23. Zhang, L., Barritt, G.J.: TRPM8 in prostate cancer cells: a potential diagnostic and prognostic marker with a secretory function? Endocr. Relat. Cancer 13, 27-38, 2006.

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24. Henshall, S.M., Afar, D.E., Hiller, J., Horvath, L.G., Quinn, D.I., Rasiah, K.K., Gish, K., Willhite, D., Kench, J.G., Gardiner-Garden, M., Stricker, P.D., Scher, H.I., Grygiel, J.J., Agus, D.B., Mack, D.H., Sutherland, R.L.: Survival analysis of genome-wide gene expression profiles of prostate cancers identifies new prognostic targets of disease relapse. Cancer Res. 63, 4196-4203, 2003. 25. Abboud, C.N., Scully, S.P., Lichtman, A.H., Brennan, J.K., Segel, G.B.: The requriments for ionized calcium and magnesium in lymphocyta proliferation. J. Cell. Physiol. 122, 64-72, 1985. 26. Modiano, J.F., Kelepouris, E., Kern, J.A., Nowell, P.C.: Requirement for extracellular calcium or magnesium in mitogen-induced activation of human peripheral blood lymphocytes. J. Cell. Physiol. 135, 451-458, 1988. 27. Jin, J. et al.: Deletion of TRPM7 disrupts embryonic development and thymopoiesis without altering Mg++ homeostasis. Science 322, 756-760, 2008. 28. Torii, S., Kobayashi, K., Takahashi, M., Katahira, K., Goryo, K., Matsushita, N., Yasumoto, K., Fujii-Kuriyama, Y., Sogawa, K.: Magnesium deficiency causes loss of response to intermittent hypoxia in paraganglion cells. J. Biol. Chem. 284, 19077-19089, 2009. 29. Cameron, I.L., Smith, N.K.R: Cellular concentration of magnesium and other ions in relation to protein synthesis, cell proliferation and cancer. Magnesium 8, 31-44, 1989. 30. Blandino, J.K., Viglione, M.P., Bradley,W.A., Oie, H.K., Kim, Y.I.: Voltage-dependent sodium channels in human small-cell lung cancer cells: role in action potentials and inhibition by LambertEaton syndrome IgG. J. Membr. Bio. 143, 153-163, 1995. 31. Laniado, M.E., Lalani, E., Fraser, S.P., Grimes, J.A., Bhangal, G., Djamgos, M.B.A., et al.: Expression and functional analysis of voltage-activated Na+ channels in human prostate cancer cell lines and their contribution to invasion in vitro. Am. J. Pathol. 150, 1213-1221, 1997. 32. Chou, C.Y., Shen, M.R., Wu, S.N.: Volume-sensitive chloride channels associated with human cervical carcinogenesis. Cancer Res. 55, 6077-6083, 1995. 33. Assef, Y.A., Cavarra, S.M., Damiano, E., Ibarra, C., Kotsias, B.A.: Ionic currents in multidrug resistant K562 human leukemic cells. Leukemia Res. 29, 1039-1047, 2005. 34. Li, F.Y., Chaigne-Delalande, B., Kanellopoulou, C., Davis, J.C., Matthews, H.F., Douek, D.C., Cohen, J.I., Uzel, G., Su, H.C., Lenardo, M.J.: Second messenger role for Mg++ vevealed by human Tcell immunodeficiency. Nature 475, 471-476, 2011. 35. Wu, N., Veillette, A.: Magnesium in a signalling role. Nature 475, 462-463, 2011. 36. Egami, K. et al.: Role of host angiotensin II type 1 receptor in tumor angiogenesis and growth. J. Clin. Invest. 112, 67-75, 2003. 37. Deshayes, F., Nahmias, C.: Angiotensin receptors: a new role in cancer? Tr. Endocrinol. Metab. 16, 293-299, 2005. 38. Lever, A. et al.: Do inhibitors of angiotensin-I-converting enzyme protect against risk of cancer? Lancet 352, 179-184, 1998. 39. Baluk, P. et al.: Cellular abnormalities of blood vessels as targets in cancer. Curr. Opin. Genet. Dev. 15, 102-111, 2005. 40. Pueyo, M. et al.: Angiotensin II stimulates endothelial vascular cell adhesion molecule-1 via nuclear factor-kappaB activation induced by intracellular oxidative stress. Arterioscler. Thromb. Vasc. Biol. 20, 645-651, 2000. 41. Fujita, M. et al.: Blockade of angiotensin AT1a receptor signaling reduces tumor growth, angiogenesis, and metastasis. Biochem. Biophys. Res. Commun. 294, 441-447, 2002. 42. Widdop, R. et al.: AT2 receptor-mediated relaxation is preserved after long-term AT1 receptor blockade. Hypertension 40, 516-520, 2002. 43. Silvestre, J. et al.: Antiangiogenic effect of angiotensin II type 2 receptor in ischemia-induced angiogenesis in mice hindlimb. Circ. Res. 90, 1072-1079, 2002. 44. Zhang, Y., Gladyshev, V.N.: Comparative genomics of trace element dependence in biology. J. Biol. Chem. 286, 23623-23629, 2011. 45. Virág, V., May, Z., Kocsis, I., Blázovics, A., Szentmihályi, K.: Magnéziumpótlás hatása a kalcium- és magnéziumszintekre, valamint a redox-homeosztázisra normolipidaemiás és alimentárisan előidézett hyperlipidaemiás patkányokban. Orv. Hetil. 152, 1075-1081, 2011.

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MOBIL AND TOTAL FORMS OF SOME TRANSITIONAL METAL CATIONS IN FOOD CHAIN OF BLACK CURRANTS CULTIVATION AND PROCESSING Sbanca Mirela, Jianu Călin, Alexa Ersilia, Rivi

Adrian, Jianu Ionel

Banat`s University of Agricultural Science Romania, Calea Aradului no.119, Timisoara, 300645, email: mirela_sbanca@yahoo.com ABSTRACT Romania has large natural possibilities through Western Plain, diligence and skill of residents in cultivation and processing of specific and quality horticultural products. In the world there are few areas where the climate, soil and diversity of spontaneous and cultivated flora can provide quality natural food products, with high nutritional value. The experimental results obtained for the heavy metal concentrations in the black currants cultivated on soils close to the C.E.T. Timişoara ash storage reveal higher concentrations for these elements. Higher concentrations for the toxic heavy metals (Cd, Pb) and for the potential toxic heavy metals (Zn, Cu) were identified in some vegetables, especially for leaf vegetables and for the root vegetables. Although some heavy metals were identified in higher concentrations, close to the toxic limits or higher, the mean values for these concentrations in the vegetables were in the range of normal limits. This fact demonstrate that the pollution of this areal is incipient and forward cannot be affirm that the heavy metal pollution process is evident, but this phenomenon could be amplified in the case of a prolonged anthropic impact, and without the specific agro-pedo-ameliorative measures. The classification of the non-polluted and polluted regions is achieved by multivariate analysis (PCA-principal component analysis) of the data using especially the Fe, Mn, Zn, and Cu concentration values for the first and second principal components, and Zn and Fe concentration values for the third principal component. INTRODUCTION Through the hilly and plain areas of the Cara -Severin and Timi counties (part of the historical Banat), Western Romania is known as an area with fruit-growing tradition. Thus, fruit and vegetables production in 2000, was 5.70% and 6.33% of country’s total production. Under the conditions of transition to a market economy and accession to the European Union, agriculture could be considered a strategic priority and the horticultural sector should be entrusted with an important competitive role in its development on modern bases. In response to these requirements and to become competitive in the European Community, Romania needs to increase and diversify quality horticulture production to at least 12-15 million tons annually. The main purpose of the research work is to determine the concentration levels of some chemical elements (Fe, Cu, Zn, Cd, Pb), defined as "heavy metals”, in black currants (Ribes nigrum) grown in hilly and plains areas of Banat, in order to determine contamination / pollution with heavy metals and identification of potential sources of pollution with such metals. To achieve the intended purpose, the following steps were taken:

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¾ knowledge of specific climatic condition for the researched area; ¾ determination of the main soil physico-chemical parameters and soil characterization; ¾ determination of heavy metals (total and mobile forms) content in soil from the investigated area; ¾ characterization of ash from the CET – Timi oara (Utvin); determination of heavy metals content; ¾ determination of pH and heavy metal content in surface waters from the investigated area; ¾ determination of heavy metals content in black currant shrub from the investigated area. MATERIALS AND METHODS Materials 1. Black currant fruits (Ribes nigrum) from 2010’s fruit harvest in Utvin area (Timi county), in the vicinity of CET Timi oara 2. All reagents (selective list) were analytical grade (Sigma Aldrich) and specific for atomic absorption spectral analysis. Methods Following analytical sequence was taken: ¾ pre-concentration of heavy metals acid extracts, when the concentration was below the analytical detection limit; ¾ comparison of experimental results obtained with the same analytical method in different laboratories or with different methods in order to establish their accuracy; ¾ tabular and graphic presentation of experimental results and their interpretation, comparatively, for the analyzed products; ¾ comparison of experimental results obtained in the investigated areas and with those from the literature. ¾ multivariate analysis (PCA - principal component analysis) to experimental data. RESULTS AND DISCUSSION The climatic parameter values from the Utvin areal are in the normal range and don't have a significative influence on the accumulation of the heavy metals in soil and plants. According to the aeolian characteristics, the higher frequency is observed for the case of wind from the North and North-East direction, but also for those from the South-West direction. Due to the fact that the ash storage is placed in the East of the Utvin village, the wind can transport dry ash and pollute the agricultural soil from this area. The chemical analysis of the ash reveals a low alkaline medium and a higher content of humus, nitrogen, phosphorus, and potassium. A higher content of heavy metals - total forms was determined in the ash samples, comparatively with the normal values for the agricultural soils, but the level of the heavy metals in soil is not limitative for the plant culture. The highest values, close to the alert thresholds, were determined for the lead, nickel, and cobalt. The alkaline ash reaction maintains these metals in forms which are inaccessible for the plants. However, an excess of heavy metals in the agricultural soils could be appear by aeolian activity, which have a negative impact on the soil and plant quality. Utvin areal soils have a supplementary anthropic charge with heavy metals, especially for Cd, Pb, Co, Cu, and Zn. The soil physico-chemical parameters maintain these metals in forms

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which are inaccessible to the plants. As a result, this soil is still non-debased by the anthropic impact of the ash from storage placed to the East side of the cultivated field. The experimental results obtained for the heavy metal concentrations in the blackberries cultivated on soils close to the C.E.T. Timişoara ash storage reveal higher concentrations for these elements. Higher concentrations for the toxic heavy metals (Cd, Pb) and for the potential toxic heavy metals (Zn, Cu) were identified in some vegetables, especially for leaf vegetables and for the root vegetables. Although some heavy metals were identified in higher concentrations, close to the toxic limits or higher, the mean values for these concentrations in the vegetables were in the range of normal limits. This fact demonstrate that the pollution of this areal is incipient and forward cannot be affirm that the heavy metal pollution process is evident, but this phenomenon could be amplified in the case of a prolonged anthropic impact, and without the specific agro-pedo-ameliorative measures. The classification of the non-polluted and polluted regions is achieved by multivariate analysis (PCA-principal component analysis) of the data using especially the Fe, Mn, Zn, and Cu concentration values for the first and second principal components, and Zn and Fe concentration values for the third principal component. CONCLUSION Can be appreciate the importance of knowledge and research extension on heavy metal (total and mobile forms) circuit (geobiochemical cycle) on black currants quality (Ribes nigrum), as nutrients. Acknowledgement. We wish to thank the Banat’s University of Agriculture Sciences and Veterinary Medicine Timişoara, Faculty of Food Technology Products, for a generous helpful of different kinds and financial support. LIST OF REFERENCES [1] Mirela Sbanca, Teză de doctorat, (în finalizare 2011), Peptide antibacteriene. Izolare, purificare, caracterizare. [2] Daniel A. Vallero, Environmental contaminants: assessment and control, 2004, Ed. Elsevier Academic Press, ISBN 0-12-710057-1, United State of America. [3] Daniel A. Vallero, J. Jeffrey Peirce, Engineering the risks of hazardous wastes, 2003, Ed. Butterworth-Heinemann, ISBN 0-7506-7742-2, United State of America. [4] Yolanda Picó, Food contaminants and residue analysis, 2008, Ed Wilson&Wilsons, ISBN 978-0-444-53019-6, Hungary. [5] S.N.Mahindru, Food Contaminants - Origin, Propagation & Analysis, 2009, Ed. A.P.H. Publishing Corporation, ISBN 81-7648-525-X, New Delhi. [6] Darsa Purnama Siantar, Mary W Trucksess, Peter M Scott, Food contaminants: mycotoxins and food allergens, 2008, Ed. American Chemical Society, ISBN: 9780841269545, USA.

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EFFECT OF SOIL PARTICLE SIZE ON COPPER AVAILABILITY Jordana Ninkov, Stanko Milić, Petar Sekulić, Tijana Zeremski-Škorić, Jovica Vasin, Srđan Šeremešić, Livija Maksimović Institute of Field and Vegetable Crops, Maxim Gorky St. 30, 21000 Novi Sad, Serbia; Faculty of Agriculture, Dositej Obradović Sq. 8, 21000 Novi Sad, Serbia e-mail: jordana.ninkov@ifvcns.ns.ac.rs ABSTRACT This paper deals with the effect of soil particle size on copper availability. Twelve vineyards, (at three depths) all on the territory of the Vojvodina Province, were observed for soil contamination with copper. Soil samples were taken in four locations (5 soil types). The samples were analyzed for total copper and available copper (in EDTA). and sequential extraction was conducted. Correlations between soil particle size and copper fractions were calculated and analyzed. The obtained results indicated that the increase in the portion of smallest soil separates, clay and silt, tended to reduce copper availability, whereas the larger separates tended to increase it. The available fractions, CuEX and CuCAR, were significantly negatively correlated with the content of clay and silt along the entire soil profile of the analyzed vineyards. Simultaneously, these two factions were positively correlated with the content of fine sand, also along the entire soil profile. The results confirmed that, when assessing the extent of soil contamination with copper, soil mechanical composition should be taken into account as an important factor of copper availability. INTRODUCTION Worldwide studies of copper levels in vineyard soils have shown that the use of copper-based pesticides constitutes a serious risk, although until recently the use of such pesticides was considered safe compared with other pesticides (Dixon, 2004; Komarek et al., 2010). When assessing the risks of copper pollution of soil, it is important to know its geochemical (mobility, reactivity) and biological properties (availability, toxicity) (Kabat-Pendias, 2004; Menzies et al., 2007). Previous studies (Kabat-Pendias and Pendias, 2001) have shown that the content of clay is crucial for copper availability. Parat et al. (2002) detected higher copper contents in silt and clay than in coarse and fine sand. In the research of Besnard et al. (2001), the largest portion of copper was detected in the clay separate of soil and in POM. High copper availability was determined in arenosol (Ninkov et al., 2009). MATERIALS AND METHODS Soil samples were taken from individual vineyards from all three grape-growing regions of the Vojvodina Province: Srem - the locations of Sremski Karlovci and Banoštor (45º 11' N, 19º 55' E and 45º 11' N, 19º 36' E, respectively), south Banat - the location of Vršac (45º 06' N, 21º 20' E), Subotica-Horgos sands - the location of Hajdukovo (45º 11' N, 19º 55' E). A total of 12 vineyards were observed from which 36 soil samples were collected.

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Data were statistically processed using STATISTICA for Windows version 8.0 (StatSoft, 2007). The samples were air-dried and milled to a particle size of <2 mm, in accordance with ISO 11464:1994. Particle size distribution was determined in the <2mm separate by the internationally recognized pipette method. The sizes of particles were defined as coarse sand (200-2000 µm), fine sand (20-200 µm), silt (<20 µm) and clay (<2 µm). Total Cu content in soil samples was measured after digestion with aqua regia (1 HNO3:3 HCl), in accordance with ISO 11466:1995. Total Cu concentration was determined by ICPOES (Vista Pro-Axial, Varian). Quality control was carried out periodically with IRMM BCR reference materials CRM-141R and CRM-142R for aqua regia digestion. Deviations were within ± 10% of the certified values. EDTA-extractable Cu was determined by the EDTA extraction protocols for IRMM BCR reference materials CRM-484: 5 g soil/50 ml EDTA concentration 0.05 mol/L pH=7.00, with the extract being used to determine the Cu content on a Varian AAS Spectra AA 600 flame system. Quality control was carried out periodically with IRMM BCR reference materials CRM 484. Deviations were within ± 10% of the certified values. EDTA-extractable Cu was regarded as an indicator of the plant-available fraction of soil Cu (Chaignon et al., 2003). Sequential extraction of Cu was performed by the method of Tessier et al. (1979). Five individual copper fractions were determined: 1. CuEX (exchangeable), 2. CuCAR (bound to carbonates), 3. CuFeMnOx (bound to Fe and Mn oxides), 4. CuOM (bound to organic matter) and CuR (residual). Copper concentrations were determined by ICP-OES (Vista Pro-Axial, Varian). RESULTS According to the content of total copper, CuT, the examined vineyard soils were found to be contaminated by copper as a result of long-term application of copper-based fungicides. Of the 36 samples analyzed, 26 of them had the Cu concentration above the critical level of 60 mg/kg (Scharmel et al., 2000). The average CuT content of 89.9 ± 45.1 mg/kg was also above the critical level. Twelve samples had the CuT content over the MAC of 100 mg/kg (Official Gazette of the Republic of Serbia, 23/94). The mechanical composition of soil in the studied vineyards varied in dependence of the different soil types in the observed locations. In the location of Sremski Karlovci, the soil type was rendzina. Its clay-silt-sand separates ranged around 20%, 40%, and 40%, respectively, which is considered as a "balanced structure" ideal from the agronomic point (Vučić,1987) . In the location of Banoštor, with the chernozem soil, the clay content was increased (about 30%), at the expense of a reduced content of silt (about 30%). In the location of Vršac, skeletal plot was present in some parts of the vineyard. The percentage of rock fragments ranged from 8.5% to 57%. Two soil types were identified in that location, vertisol and regosol. In the location of Hajdukovo, the soil type was arenosol and all samples belonged to the texture class of loamy fine sand. The portions of clay and silt were small (<5%) while the portion of fine sand ranged from 55% to 94%. The sum of the first two fractions in the sequential analysis is considered as the content of available copper: exchangeable (CuEX) and copper bound to carbonates (CuCAR). The content of available copper (CuEX +CuCAR) is highly correlated with CuEDTA, r = 0.81. According to Karczewska (1996) (cit. Pieterzak and McPhail, 2004), the fractions CuR and CuFeMnOx are the least active and they have the lowest impact on living organisms. The

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fractions CuOM and CuCAR are sensitive to changes in soil conditions, such as organic matter demineralization, or changes in redox potential and pH, which may increase their mobility. In this study, the largest portion of copper was located in non-available fractions, which was in agreement with literature data (Scharmel et al., 2000; Chaignon et al., 2003; Pieterzak and McPhail, 2004; Fernandez-Calvino et al., 2008; Komarek et al., 2010). As stated in literature (Adriano, 2001; Kabata-Pendias and Pendias, 2001), the mechanical composition of soil, i.e., the portion of clay, had a decisive impact on copper availability. In the analyzed vineyard soils, copper availability was reduced as the clay content increased along the entire soil profile. Table 1. Correlations between different copper fractions and soil separates in the layer 0-15 cm Clay Silt Fine sand Coarse sand Soil depth (<2 µm) (<20 µm) (20-200 µm) (200-2000 µm) 0-15cm % % % % CuEX % -0.88** -0.83** 0.94** 0.67* CuCAR % -0.65* -0.72** 0.78** 0.47 CuFeMnOx % -0.31 0.09 0.05 0.21 CuOM % 0.20 -0.31 -0.13 0.37 CuR % 0.33 0.55 -0.33 -0.59* CuT mg/kg 0.56 0.36 -0.60* -0.19 CuEDTA mg/kg 0.29 0.03 -0.29 0.06 CuEDTA/T % -0.78** -0.90** 0.92** 0.65* * p≤0.05; ** p≤0.01

The available fractions CuEX and CuCAR were significantly negatively correlated with the contents of clay and silt along the entire profile of vineyard soil (p <0.01), except for the correlation between CuCAR and the clay content in the 0-15 cm layer (p <0.05). On the other side, these two Cu factions were positively correlated with the content of fine sand, also along the entire profile (p <0.01; Table 1). The content of CuEX was positively correlated with the coarse sand separate in the soil layers 0-15 and 30-60 cm. The indicator of copper availability, CuEDTA/T showed the same significant correlations as the exchangeable fraction (CuEX) except for the clay content in the layer 30-60 cm, where the correlation was nonsignificant (Table 1). The obtained results indicated that copper availability went down as the portion of the finest soil separates, clay and silt, increased, while it went up with th eincrease in the portion of the coarse separates. The positive correlation (p <0.05) between the residual copper (CuR) and the content of silt in the layer of 15-30 cm also confirmed this pattern. In a study of calcareous vineyard soils (Parat et al. 2002), copper content was higher in the silt and clay separates than in the coarse and fine sand. Also, the negative correlation (p <0.05) between the portion of fine sand and CuT in the surface layer of the vineyard soil indicated that all other copper fractions were prone to leaching in soils of light mechanical composition. CONCLUSIONS • Estimated on the basis of the content of total copper (CuT), the vineyard soils were contaminated by this element as a result of a long-term application of copper-based fungicides. The average value of CuT, 89.9 ± 45.1 mg/kg, was above the critical level. Values over the MAC were recorded in 12samples.

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• The available copper fractions and availability indicators were significantly negatively correlated with the portion of clay particles and also positively correlated with the portions of fine and coarse sand. These values confirmed that copper is less mobile in soils with a high portion of clay. • The obtained results confirmed that, when assessing the risk of soil contamination with copper, it is necessary to analyze the mechanical composition of soil as an important factor in its accessibility. LIST OF REFERENCES Adriano D. (Eds.). Trace Elements in Terrestrial Environments, Biogeochemistry, Bioavailability and Risks of Metals. Second Edition. Springer. New York. USA. 2001. p. 508-509. Besnard E., Chenu C., Robert M. (2001). Influence of organic amendments on copper distribution among particle-size and density fractions in Champagne vineyard soils. Environmental Pollution. 112. p. 329-337. Chaignon V., Sanchez-Neira I., Herrmann P., Jaillard B., Hinsinger P. (2003). Copper bioavailability and extractability as related to chemical properties of contaminated soils from vine-growing area. Environmental Pollution. 123, p. 229-238. Dixon B. (2004). Pushing Bordeaux mixture. The LANCET Infectious Diseases. 4, p. 594. Fernandez-Calvino D., Pateiro-Moure M., Lopez-Periago E., Arias-Estevez M., NovoaMunoz J.C. (2008). Copper distribution and acid-base mobilization in vineyard soils and sediments from Galicia (NW Spain). European Journal of Soil Science. 59, p. 315326. Komarek M., Čadkova E., Chrastny V., Bordas F., Bollinger J. C. (2010). Conatmination of vineyard soils with fungicides: A review of environmental and toxicological aspects. Environment International. 36, p. 138-161. Kabata-Pendias A. (2004). Soil-plant transfer of trace elements - an environmental issue. Geoderma. 122, p. 143-149. Kabata-Pendias A. and Pendias H. (Eds.). Trace elements in soils and plants, 3rd ed. CRC Press, USA. 2001, p. 106-117. Menzies N.W., Donn M.J. and Kopittke P.M. (2007). Evaluation of extractants for estimation of the phytoavailable trece metals in soils. Environmental Pollution. 145, p. 121-130. Ninkov J., Paprić Đ., Sekulić P., Zeremski-Škorić T., Vasin J., Milić S., Šeremešić S. (2009) Characteristics of arenosol under vineyard. Proc. 16th Int. Symp. on Analytical and Environmental Problems. 28.09.2009. Szeged, Hungary. p. 215-218. Parat C., Chaussod R., Leveque J., Dousset S., Andreux F. (2002). The rationalship between copper accumulated in vineyard calcareous soils and soil organic matter. European Journal of Soil Science. 53, p. 663-669. Pietrzak U. and McPhail D.C. (2004). Copper accumulation, distribution and fractionation in vineyard soils of Victoria, Australia. Geoderma. 122, p. 151-166. Scharmel O., Michalke B., Kettrup A. (2000). Study of the copper distribution in contaminated soils of hop fields by single and sequential extraction procedures. The Science of the Total Environment. 236, p. 11-22. Vučić N., Water, Air and Thermal Regime of Soil. Vojvodina Academy of Scence and Arts, Matica Srpska, SFRJ, 1987. Tessier A., Campbell P.G.C., Bisson M. (1979). Sequential extraction procedure for the speciation of particulate trace metals. Analytical Chemistry. 51:7, p. 844-851.

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REPRODUCIBILITY AND ACCURACY PROBLEMS OF THE GASCHROMATOGRAPHIC RESPONSE FACTORS FOR THE REACTION PRODUCTS RESULTING FROM THE CATALYTIC BIO-ETHANOL CONVERSION Orsina Verdes, Livia Avram, A. Popa and V. Z. Sasca Institute of Chemistry Timisoara-Romanian Academy, Bd. M. Viteazul 24, 300223Timisoara, Romania, E-mail: vsasca@acad-icht.tm.edu.ro Introduction The heteropoly compounds-HPCs are strong acid and they are much more active as ordinary solid acids, for example, zeolites and silica-alumina. Among the HPCs, the H3PW12O40-H3PW shows the highest acidity. The conversion of alcohols to hydrocarbons on acidic solid catalysts was one of the most studied reactions, especially ethanol conversion on the H3PW and their acidic salts as the production and use of bio ethanol increase. In this work was studied the quantitative analysis of the reaction products from the catalytic conversion of ethanol on the H3PW and its Cesium salts and the specific problems of the accuracy and the reproducibility of the results. Experimental The conversion of ethanol was studied on the H3PW and CsxH3-xPW, x=1; 2; 2.25, 2.5 and 3 catalysts by pulse reactant technique-PRT and continuous flow of reactant technique-CFRT. A micro reactor connected to GC-FID was operated by PRT (Fig.!) and CFRT (Fig. 2) at temperatures between 473 K and 623 K. The reaction products observed were ethylene, diethyl ether, C1-C6 hydrocarbons and unreacted ethanol.

Fig.1. The installation scheme for catalytic the activity measurement by PRT: 1. Six port valve; 2. Gas sample loop; 3. Liquid sample evaporator; 4. Microreactor heated by electric furnace; 5. Gas-chromatograf; 6. Integrator.

Fig.2. The installation scheme for catalytic the activity measurement by CFRT: 1. Four port valve; 3. Liquid sample evaporator; 3. Micro reactor heated by electric furnace; 4. Four port valve, 5-6 Six port valve with gas sample loop; 7. Gas-chromatograph; 8. – Integrator.

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The GC-FID was equipped with a stainless steel column of 3 m length, 2 mm inner diameter packed with Porapak QS 80-100 mesh. The N2 carrier gas with the flow of the 30 cm3/min was used. The splitting was of 1:6 volume ratio. For a better separation of reaction products, a temperature programme for the column was set up: 5 min at 323 K, then heating from 323 K to 473 K with the heating rate of 10 K/min and the last an isothermal heating at 473 K for 5 min. The total time for a complete analysis was 25 min. The calibration curves and response factors for the reaction products were determined by using the liquid samples of the ethanol or ethanol-diethyl ether-water, respectively, gas samples of pure methane, propylene, isobutylene and n-hexane in liquid phase. The liquid samples were introduced in GC with a 10 microliters Hamilton syringe, type 801 RN and the gas samples were introduced by the six-port valve from the loops of 0.5-1.5 ml volume or with a gastight Hamilton syringes, type 1002 LTN of 2.5 ml and type 1001 of 1.0 ml. Results and discussion The ethanol conversion over H3PW and its Cs salts as catalysts led to ethylene as main reaction products. The secondary reaction products are: methane, C2 hydrocarbon fraction (Ethylene, Ethane), C3 hydrocarbon fraction (propene, propane), C4 hydrocarbon fraction (Isobutylene, Butene, Isobutane, and Butane), C5 hydrocarbon fraction (Isopentene, Isopentane, Pentane), C6 hydrocarbon fraction (Isohexene, Isohexane, and Hexane) and Diethyl ether. The retention time for the reaction products are showed in Table 1 and two examples of typical chromatograms can be seen in Fig. 3a,b. Table 1. The reaction products from the ethanol conversion on CsxH3-xPW catalysts and their retention time No Reaction products Retention time, min 1 Methane 1.4-1.5 2 Ethylene, Ethane 3.7-4.0; 4.5-5 3 C3 fraction: Propylene, Propane 9.8-10.7 C4 fraction: Isobutylene, Butene, 4 11.5-13.0 Isobutane, Butane 5 Ethanol 13.2-13.9 6 Ethylic ether 15.8-16.8 C5 fraction: Isopentene, Isopentane, 7 17.5-19.0 Pentane C6 fraction: Isohexene, Isohexane, 8 20.0-23.0 Hexane The normal symmetrical shape was observed for the main peaks (Ethylene, Propene, Isobuthylene, Ethanol and Ethylic ether), which is an important requirement for the accuracy and reproducibility of analyses results. The calibration curves are showed in Fig. 4a,b,c.d. for the main reaction products. The concentration ranges of calibration curves for all reaction products were in concordance with the experimental values obtained of catalytic test of activity for ethanol conversion, what is a guarantee for the accuracy of the analyses results.

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a) b) Fig. 3a,b. The chromatograms of reaction products for ethanol conversion on Cs2.5H 0.5PW at the temperature of 523 K, continuous flow of reactant: a) 11mol% EtOH; b) 22 mol% EtOH 4,0E+07

Peak area, a.u.

3,0E+07 y = 487550x - 543864

Fig. 4. The calibration curves for the ethanol

R2 = 0,9962

2,0E+07

Series1 Serie 2

1,0E+07

y = 366946x + 1E+06 R 2 = 0,9988

0,0E+00 0

10

20

30

40

50

60

70

Ethanol, micromoles

Peak area, a.u.

1,2E+07 y = 944592x - 185376 R2 = 0,992

9,0E+06

6,0E+06

Fig. 5. The calibration curves for the ethylic ether

Series 1 Series 2

3,0E+06

y = 665294x + 648058 R2 = 0,9862

0,0E+00 0

2

4

6

8

10

12

Ethylic ether, micromoles

161

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011 6,0E+07 y = 637700x - 230918 R2 = 0,9999

Peak area, a.u.

5,0E+07 4,0E+07

y = 612372x - 238337 R2 = 0,9991

3,0E+07

y = 568130x + 481373 R2 = 0,9991

2,0E+07

Fig. 6. The calibration curves for the ethylene

Series 1 loops Series 2 loops

y = 487622x - 613437 R2 = 0,9992

1,0E+07

Series 3 syringe Series 4 loops

0,0E+00 0

10

20

30

40

50

60

70

80

Ethylene, micromoles

Peak area, a.u.

8,0E+06 6,0E+06

y = 1064601x - 41684 R2 = 0,9875

4,0E+06 2,0E+06

y = 891228x - 51086 R2 = 0,9986

0,0E+00 0

2

4

Series 1

Fig. 7. The calibration curves for the isobutylene

Series 2 6

Isobutylene, m icrom oles

The precision of the analyses can be evaluated by the correlation coefficient-R values. The precision for the analyses of diethyl ether and gas samples (in the cases of introduction with syringes) was poorly, as can be observed from the Fig. 5 and 7(Series 2). The response factors were calculated from the correlation equation y=Ax+B as F=1/A, micromoles/a.u and the confidence in their values is affected of the all elements which affect the accuracy of the analyses results. Conclusions The reproducibility of the analyses results depend of the constant values during the measurements for the flow of carrier gas, hydrogen, air and the splitting ratio also. The chromatographic peaks have to be of normal shape, with clear separation between them, it means good choices for column package and work conditions (carrier gas type and flow, hydrogen and air flow, temperature programme for column), which is a requirement for a good accuracy. The concentration ranges of calibration curves for all reaction products were in concordance with the experimental values obtained of catalytic test of activity for ethanol conversion, what is a guarantee for the accuracy of the analyses results. The gas samples are preferable to be introduced in GC with six-port valves from loops for higher reproducibility and accuracy. The liquid samples injection for obtaining high reproducibility and accuracy need some precautions like: - the reading carefully of the injected sample volume, - a syringe tight to pressure of the column head and a smooth and continuous plunger motion during injection.

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ORGANIC PRODUCTION IN THE FUNCTION OF HEALTHY AND SAFE FOOD Branko Vidicki Faculty of Agriculture, University of Novi Sad, Trg Dositeja Obradovica 8, 21000 Novi Sad, Serbia e-mail: branko.vidicki@vojvodina.gov.rs ABSTRACT The increase in the population on the Earth has led to higher demand and consumption of food. The need for food has prompted mankind to increase food production. Due to lack of arable land, people had to access new technologies which caused an increased use of pesticides and chemical supplements in modern agriculture. The use of various additives in agricultural production has led to adverse effect of agriculture on the environment and human health. Over the last century, various pesticides have been in use, many of which have later been banned from use due to adverse health effect. In recent years there has been an awareness development for healthy and safe food. Increased awareness of safe food has led to the organic farming as a means of ensuring safe food. This paper presents organic farming as a generator of safe food in terms of environmental protection and human health. INTRODUCTION The impact of current consumer society, and the rapidly increasing population on the planet Earth, leading to the development of agriculture in order to increase productivity and yield. Uncontrolled and unnecessary use of various hazardous chemicals has reduced soil quality and fertility to a minimum, and agricultural products have become contaminated with harmful substances. Modern agriculture is based on quantity and profit, disregarding the quality and safety of food and potential health risks of humans and animals caused by excessive use of pesticides. Concentration at the economic aspects and financial benefits derived from agricultural production, people neglected the environment whose degradation directly and indirectly affects human health. The solution to problems must be sought in the development of a sustainable society that respects the environmental and health principles. One way of overcoming the problem is the organic production. According to the Law on Organic Production (“Sl. Glasnik RS” No. 30/2010) organic production is defined as “production of agricultural and other products based on applying organic production methods in all stages of production, which excludes the use of genetically modified organisms and products consisting of or derived from genetically modified organisms and the use of ionizing radiation, in accordance with this Law and regulations adopted thereunder”. Organic farming excludes the use of pesticides, synthetic chemical insecticides, herbicides, growth regulators, hormones, antibiotics, artificial fertilizers and genetically modified organisms (GMOs). Growing food by organic farming respects ecological principles that include the application of agro-technical measures that are consistent with the environment and not damaging to human health. Food production based on natural principles is the basis of food production in the years to come. Farmers need to

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consider the total health safety of food in order to avoid its adverse effect on human and animal health. The development and popularization of organic production occurs in response to the increasing negative effects on human health and the environment, which are associated with conventional farming. New scientific knowledge about the harmful effects of pesticides and possible radioactive components in mineral fertilizers put organic production at the center of attention, as a way of obtaining healthy food with no adverse health effects. The organic production is based on few basic principles: - The Principle of Health – Organic agriculture should sustain and increase the quality of soil, plants, animals, humans and the planet as a whole. - The Principle of Ecology – Organic agriculture should be based on living ecological systems and cycles, to support them and help their conservation. - The Principle of Justice – Organic agriculture should be based on fair relations with the environment, nature and life. - The Principle of Nurturing and Care – Organic agriculture should be managed in a precautionary and responsible manner to preserve the health and well-being of present and future generations and the ecosystem. Organic farming can be seen from several perspectives which prove the fact that the organic way of getting food is in full compliance with all the modern principles of sustainable development. The reasons justifying the organic production can be classified into four groups: -

Health Environmental, Economic, Political.

Eliminating the use of products that adversely affect human health, organic farming is characterized as a responsible business that cares for the health and the environment. Organic farming produces safe healthy food that does not contain harmful substances. The use of the chemicals in conventional agriculture, such as pesticides, insecticides, herbicides, hormones, antibiotics and GMOs leads to human health threats, especially vulnerable groups such as children and the elderly. The use of harmful substances is forbidden in organic farming, so there is no risk to human health, which places the organic production in safe procedures for obtaining food. Analysis of organic foods has shown that the food obtained in that manner has much more vitamins and minerals. Studies have shown that organic food contains on average 63% more potassium (K), 73% more iron (Fe) and 125% more calcium (Ca) than the products obtained by conventional agriculture. Dry matter in the products obtained by organic production is increased by up to 30% comparing to products of conventional agriculture. Organic production is fully in line with the principles of sustainable development and it doesn’t have any negative environmental impacts in any stage of production. Moreover, organic production is a natural way to restore soil and protect biodiversity of the area in which the organic production is applied. Great momentum in the improvement and implementation of organic agriculture in the world has led it become the most developed branch of economic growth. Dissemination of method and philosophy of obtaining food from organic farming increases rural development, increases export leading to higher economic growth, optimizing the use of natural resources. The development of organic farming in the world is based on the increasing demand for certified organic food. Europe and the U.S. have a continuous shortage of goods because the

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production does not meet the overall demand. Over 120 countries practices organic farming worldwide. Only 6% of the world countries have more than 10% share of the total agricultural land for organic farming, while in Europe, that percentage is lower. The European Union plans to increase organic production by 20% by the year 2020. The total value of organic farming worldwide in 2008. was $45 billion. Organic farming in Serbia is developing in the last 20 years, and the most intensive growth was registered in the last five or six years. Demand for organic products in Serbia is greater than supply, which is why the most common products on the market are from import. According to estimates, Serbia has below 1% of total arable land under organic crops which is estimated at more than four million hectares. Organic food production is 13 times lower than the European average, which indicates that the attitude towards organic production has to change. There is an interest of potential investors for investment in the sector of organic production, but Serbia has under-developed retail network, and failure to recognize the inaccurate labeling of organic products. As noted, Serbia is not investing enough in the development of organic farming. Based on information received by the Ministry of Agriculture from the authorized certification organization until February 2009. Serbia presented the following facts for the development od organic farming: - Total number of organic producers is 224 (only 37 manufactures have contracts with authorized organizations for certification), - Total area covered by organic production is 596 ha, of which: o 330 ha is certified by authorized organization for organic production, 89 ha is used for growing specific crops and 240 ha fall under meadows, pastures and forests, o 265 ha is in the process of conversion - Total production of certified organic vegetable in 2008 is about 629.551 kg (39.500 kg of cereals, 15.500 kg of fodder and forage crops, 7.600 kg of industrial crops, 526 kg of culinary herbs, 425 kg of medicinal herbs, 430 kg of vegetables and 95.500 kg of fruit). In the last few years, Serbia is making great efforts to reach European and international standards in area of organic production. In December 2010. Serbia applied for inclusion in the list of countries whose organic products can be sold in EU. Ministry of agriculture has issued eight licenses in 2011 for certifying organic products. However, these certificates are valid only for the domestic market, while exported goods need to have certificates issued in companies that meet the requirements and standards prescribed in the EU. This process makes it difficult for local farmers who wish to export to obtain certificates since it brings additional financial burden. Even foreign companies and representative offices located in Serbia can not issue a certificate for export to EU, only their parent companies can do that. Weaknesses of Serbian organic production are small market and low utilization possibility in EU market. Farmer population in Serbia is, mostly, under-educated, and this applies especially to the sector of organic production. Environmental protection and human health are among the essential conditions that any country joining the EU should comply. EU members agree that the environmental protection of the environment, human health and healthy food are the EUs health priorities for the future. Compliance with these priorities and the adoption of acts that support that view will be the rule for all the countries planning to join the EU. MATERIAL AND METHOD The method used to obtain data included the testing of customers in two markets in Vrbas (“Big market” and “Small market”) by the survey. Respondents were random buyers of

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agricultural products. The survey was filled by 65 customers from various gender and age distribution. The aim of the survey was on-site review on population commitment to buy organic food. In addition to consumer surveys, the survey of farmers in village Ravno Selo was conducted. Farmers included in survey all had modern agricultural machinery necessary to produce safe food, and had between 60 and 100 ha of arable land in their possession. RESULTS AND DISCUSSION Based on the responses from the survey, the following results were obtained. Of the 65 surveyed consumers in Vrbas markets, 21 (32.3%) pays attention to whether a product is organic, 30 (46.2%) do not pay attention whether the food is produced organically, and 14 (21.5%) respondents said that they do not care.

40 30 20 10 0

Market places in Vrbs

Pays attention

21

Do not pay attention

30

Do not care

14

21.5% Pays attention

46.2%

32.3%

Do not pay attention Do not care

When asked “Would you be willing to produce organic food”, 7 (23.3%) out of 30 interviewed farmers from village Ravno Selo answered they would participate in organic production if they had knowledge and the condition for such production, 10 (33.3%) responded they are interested only in profit, while 13 (43.3%) said they are considering switching to organic food production.

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011 15 10 5 0 Yes

7

No, only profit

10

Considering

13

23.3% Yes

43.3%

No, only profit Considering

33.3%

CONCLUSION •

The education of citizens, potential consumers of healthy organic food, as well as the education of independent agricultural producers is needed. A comprehensive support to producers of organic food is also needed, financial and production benefits and help in marketing approach. Incentives from competent authorities are needed in all aspects of production and sales so the organic products are cheaper and more affordable to consumers.

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KÜLÖNBÖZŐ NPK KEZELÉSEK HATÁSA A CSEMEGEKUKORICA TERMÉSMINŐSÉGÉRE Orosz Ferenc1,2, Slezák Katalin1 1

Budapesti Corvinus Egyetem, Kertészettudományi Kar, Zöldség- és Gombatermesztési Tanszék, H-1118 Budapest, Ménesi u. 44. 2 Sapientia EMTE, Műszaki- és Humántudományok Kar, Kertészeti Tanszék, 540485 Marosvásárhely, Şos. Sighişoarei 1C. e-mail: ferenc.orosz@uni-corvinus.hu ABSTRACT In our trial, we studied, if the double incresing of nutrient elements (NPK) dosis more than recomanded by nutrient balance approach system, we can improve yield’s quantity and quality of sweet corn. The treatment without fertilization – based on symptoms, because of nitrogen deficiency – produced by the measured properties weaker results compared to the other treatments. The plants from fertilized treatments did not produce any deficiency or overdose symptoms. Compared to control treatment, the application of higher fertilizer doses did not influence significantly crop’s development, so we consider adequate to apply, in similar growing circumstances the fertilizer dosis included into control treatment. BEVEZETÉS, IRODALMI ÁTTEKINTÉS Az élelmiszeripari feldolgozásra szánt csemegekukorica termesztése teljes mértékben gépesített. Magyarországon túlnyomórészt (a termőterület 95%-án) termesztett ún. „normálédes” fajták optimális betakarítási érettsége kedvező időjárási feltételek között is csupán 3-4 napig áll fenn. A gépi betakarítás egymenetes, feltétele az egyszerre érés. Egyöntetű, nagy termésre képes állomány kialakításához megfelelő tápanyag-ellátásra van szükség. A csemegekukorica nagy tömegű zöld levelet és szárat fejlesztő, tápanyagigényes növény. 16 t/ha-os hozam esetén 1 t termés előállításához 9 kg N-re, 3,6 kg P2O5-ra és 10,2 kg K2O-ra van szüksége. Közepes tápanyag-ellátottságú talajon, mérleg szemléletű tápanyag-gazdálkodást folytatva, ugyanehhez a termésátlaghoz 216 kg N, 92 kg P2O5 és 229 kg K2O hatóanyagot célszerű kijuttatni (Terbe és Csathó, 2004). A nitrogén alapvető fontosságú a zöldtömeg és a hozam szempontjából. A termés nagyságát elsősorban a nitrogén határozza meg, amennyiben a többi elem nem kerül minimumba. A nitrogén adag nagyságát a termőhelyi viszonyok, a vízellátás valamint a fajták befolyásolják (Bocz és Nagy, 2003). Hiányakor gátolt a fehérjeképződés, ezáltal az enzimek szintézise, végső soron az egész növény fejlődése és növekedése lelassul, a termés csökken. Jól reutilizálható tápelem, ezért hiányát az idősebb levelek sárgulása jelzi. A levelek a megszokottnál kisebbek, ezzel szemben a gyökerek hosszúak, így a gyökér/hajtás arány megváltozik (Zsoldos, 1998). Túladagolása hosszabbítja a tenyészidőt, gyakori a szárdőlés. A foszfor elősegíti a gyökérfejlődést, a megtermékenyülést és a szemképződést. Szerepe van még többek között a nukleinsav-szintézisben, membránszintézisben, fotoszintézisben, légzésben, redox folyamatokban, enzimaktiválás/dezaktiválásban, szénhidrogén metabolizmusban és a N fixációban (Vance et al., 2003). Hiánya a növény jellegzetes lilás elszíneződését eredményezi, a foszfortöbblet pedig növeli a fattyak számát. Gabonaféléknél kimutatták, hogy a foszfor kedvező hatással van a betakarítási időpont előbbre hozatalára is (Kádár et al., 1984), hiány esetén az érés elhúzódik.

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A kálium létfontosságú elem a növény vízháztartásában és a keményítőképzésben. A jó K ellátottság növeli a szárszilárdságot. Felvétele a tápelemek közt a leggyorsabb, de a vegetatív részekből aránylag kevés vándorol a szemekbe. Hiánya főleg a mellékgyökerek fejlődését gátolja, fokozza a párologtatást. Hiányában a levelek sárgulnak és a levélszélek barnulva elszáradnak, a cső csúcsán a szemek nem fejlődnek ki tökéletesen (Bergmann, 1979). Kísérletünkben vizsgáltuk, hogy a 2003-2004-ben kidolgozott „Környezetkímélő tápanyag-gazdálkodási rendszer”-ben, mérlegszemléletű tápanyag-gazdálkodáshoz ajánlott tápanyag-adagok emelésével növelhető-e a csemegekukorica termésmennyisége, illetve a csövek minősége. ANYAG ÉS MÓDSZER A kísérletet 2008. évben, a Budapesti Corvinus Egyetem Kertészettudományi Kar Kísérleti Üzemében (Soroksár) állítottuk be. A tábla talaja gyengén humuszos homoktalaj, a kísérlet indítása előtt vett minták alapján az alábbi tápanyag-ellátottsággal jellemezhető: N – igen gyenge; P – igen jó; K – jó. A talajvizsgálati eredmények alapján a célkitűzésben említett trágyázási rendszert alapul véve az alábbi kezeléseket állítottuk be (mérlegszemléletű tápanyag-utánpótlás, 16 t/ha tervezett termésátlag): 1 = Nullkontroll (trágyázás nélkül) 2 = N-P-K (kontroll): 222,5 kg N; 22,5 kg P2O5; 143,5 kg K2O hektáronként; 3 = 2N-P-K: 445 kg N; 22,5 kg P2O5; 143,5 kg K2O hektáronként; 4 = N-2P-K: 222,5 kg N; 45 kg P2O5; 143,5 kg K2O hektáronként; 5 = N-P-2K: 222,5 kg N; 22,5 kg P2O5; 287 kg K2O hektáronként; A sókártétel elkerülésére a nitrogént az 1-4-5. kezeléseknél három egyenlő részletben (indítótrágyázás + 2 fejtrágyázás), a 3. kezelésnél öt egyenlő részletben (indítótrágyázás + 4 fejtrágyázás) juttattuk ki, s két részletben szórtuk ki az 5. kezelés káliumadagját is. Az első fejtrágyázások ideje a növények 6 lombleveles állapotában volt, utána hetente (3. kezelés, N), illetve a címerek megjelenésekor (1-4-5. kezelések második N adagja) trágyáztunk. A tápanyagot Ammóniumnitrát (34% N), Szuperfoszfát (19,5% P2O5), valamint Kálisó (60% K2O) műtrágyákkal juttattuk ki. A tesztfajta a Spirit volt (85 napos tenyészidejű, normálédes hibrid). A kísérlet főbb technológiai paraméterei az alábbiak voltak: – vetés időpontja: IV. 24. – vetésmélység: 3 cm – növényelrendezés: 75 x 22 cm (60607 tő/ha) – egy parcella területe: 6 x 7 m (8 párhuzamos sor, soronként 30 vetett mag) – ismétlésszám: 4 – öntözési mód: esőszerű – betakarítás ideje: VII. 14 (főszedés). A kezelések összehasonlítására az alábbi tulajdonságok alakulását vizsgáltuk: – termésminőség: csőtömeg (csuhés és fosztott, gramm), terméskihozatal (fosztott/csuhés tömeg, %), csőhossz (teljes és szemekkel berakódott, cm), berakódási % (berakódott/teljes csőhossz, %), csőátmérő (legvastagabb részen, mm), sorok egyenessége (1-9 pont, 9 pont = egyenes), szemek szárazanyag-tartalma szedéskor (érettség, %).

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A méréseknél a parcellák középső négy sorát vettük figyelembe, a termés minőségi mutatóit 20 átlagos cső vizsgálatával jellemeztük. A statisztikai kiértékelést a RopStat 1.1. program segítségével végeztük (Vargha, 2007). EREDMÉNYEK A termésmennyiségre vonatkozó adatokat az 1. táblázatban foglaltuk össze. Csőtömeg (csuhés és fosztott) tekintetében a nullkontroll lényegesen nem maradt el a többi kezeléstől (1. táblázat). A többi kezelést nézve megállapítható, hogy a legnagyobb tömegű csöveket az 4. illetve az 5. jelű (emelt P, illetve K adag) kezelésekben szedtük, ezek előnye a többi trágyázott kezeléshez viszonyítva statisztikailag is kimutatható mértékű volt. A fosztott és csuhés tömeg arányát tekintve a nullkontroll kezelés volt a legkedvezőbb, de közötte, valamint a többi kezelés között nem volt szignifikáns a különbség. 1. táblázat. A csövek tömege (Soroksár, 2008) Csuhés csőtömeg Fosztott csőtömeg Terméskihozatal Kezelés (gramm) (gramm) (%) a a 1 = Nullkontroll 279 231 82,79a 2 = N-P-K (kontroll) 282a 226a 80,14a 3 = 2N-P-K 308b 247b 80,19a a a 4 = N-2P-K 287 236 82,22a 5 = N-P-2K 313b 255b 81,47a Szd95% 27,75 16,14 nincs * a számok melletti különböző betűk a kezelések közti különbséget jelölik (SzD 95%) A csövek hosszáról (2. táblázat) is megállapítható, hogy a statisztikai vizsgálatok a trágyázott kezelések között az 5. kezelés esetében tapasztaltunk lényeges különbséget, míg a trágyázás nélküli nullkontroll parcellákon fejlődött tövek jelentősen rövidebb csöveket neveltek, mint a többi kezelés növényei. A berakódási arányban ez a különbség nem jelentkezett markánsan. Csőátmérő tekintetében a 2. kezelés (kontroll) és az 5. kezelés (emelt K adag) lényegesen különbözött a többi kezelés csőátmérőjének alakulásától. A sorok egyenessége az emelt tápanyagszintű kezelésekben kissé kedvezőbben alakult, mint a nullkontroll, és kontroll kezelésekben, de a különbség a kezelések között nem volt szignifikánsnak nevezhető. Legkedvezőbbnek az emelt foszfor- és káliumszint mutatkozott e paramétert tekintve. A szemek szárazanyag-tartalma – mely jelzi az érési állapotot – a nullkontroll esetében volt a legalacsonyabb (25,21%), a 2. kezelésben a legmagasabb (25,47), a másik három kezelésben köztes adatokat (25,35-25,44%) mértünk. Az eredmények szerint a trágyázott kezelések között nem volt szignifikáns a különbség. 2. táblázat. A csövek hossza, átmérője és a szemsorok szabályossága (Soroksár, 2008) Sorok Teljes Berakódott Berakódási Csőátmérő egyenesKezelés hossz (cm) hossz (cm) % (mm) sége (pont) a a a a 1 = Nullkontroll 17,37 15,54 89,46 44,52 6,81a b a a b 2 = N-P-K (kontroll) 17,88 15,38 86,01 50,56 7,15a 3 = 2N-P-K 17,75b 15,63a 88,05a 45,28a 7,19a b b a a 4 = N-2P-K 17,86 16,14 90,36 44,92 7,25a 5 = N-P-2K 18,53c 17,50c 94,42a 50,80b 7,28a Szd95% 0,59 0,72 nincs 0,78 nincs

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* a számok melletti különböző betűk a kezelések közti különbséget jelölik (SzD 95%) KÖVETKEZTETÉSEK Eredményeink szerint a „Környezetkímélő tápanyag-gazdálkodási rendszer”-ben, mérlegszemléletű tápanyag-gazdálkodás mellett, a kísérleti terület talajadottságait figyelembe vevő ajánlás megfelelő termésmennyiség és -minőség elérését teszi lehetővé. A trágyázás nélküli kezelés – a tünetek alapján főként a nitrogénhiány következtében – esetében alacsony értékeket mértünk a többi kezeléshez viszonyítva, ugyanakkor a trágyázott kezelésekben a növények nem mutatták a szakirodalomból ismert hiánytüneteket, vagy túltrágyázás jeleit. A kontrollként vizsgált, az említett rendszer által ajánlott trágyaadagokhoz képest a többlet trágyázás kevés esetben változtatta meg lényegesen az állomány fejlődését, így megfelelőnek tartjuk a kontroll kezelésben szereplő műtrágya adagok használatát, a kísérlethez hasonló termesztési körülmények között. KÖSZÖNETNYILVÁNÍTÁS Köszönetünket fejezzük ki a Nemzetközi Káli Intézetnek (I.P.I,, Horgen), a kísérlethez nyújtott szakmai és anyagi támogatásért. IRODALOM Bergmann, W. (1979). Termesztett növények táplálkozási zavarainak előfordulása és felismerése. Mezőgazdasági Kiadó, Budapest. Bocz E., Nagy J. (2003). A kukorica nagy termésének feltételei. Gyakorlati Agrofórum Extra, 14 (2) 2-3. p. Kádár I., Csathó P., Sarkadi J. (1984). A szuperfoszfát tartamhatásának vizsgálata őszi búza monokultúrában. I. Talajvizsgálati és szemterméseredmények. Agrokémia és Talajtan. 33 (2) 375-390. p. Terbe I., Csathó P. (szerk) (2004). Környezetkímélő tápanyag-gazdálkodás a szabadföldi zöldségtermesztésben. Budapesti Corvinus Egyetem Kertészettudományi kar, Zöldségés Gombatermesztési Tanszék – MTA Talajtani és Agrokémiai Kutatóintézet. Budapest. Vance, C.P., Uhde-Stone, C., Allan, D.L. (2003): Phosphorus acquisition and use critical adaptation by plants for securing a nonrenevable resource. New Phytologist, 157, 423-447 p. Vargha A. (2007). Matematikai statisztika pszichológiai, nyelvészeti és biológiai alkalmazásokkal. Budapest, Pólya Kiadó. Zsoldos F. (1998). A növények ásványos táplálkozása. In: LÁNG F. (szerk.) Növényélettan. Budapest, ELTE Eötvös Kiadó. 119-175 p.

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WASTEWATER CHARACTERISATION OF SCREEN PRINTING Jelena Kiurski, Maja Djogo, Maja Turk Sekulić, Savka Adamović, Ivana Oros, Jelena Krstić, Mirjana Vojinović Miloradov Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovića 6, Novi Sad, Serbia e-mail: kiurski@uns.ac.rs ABSTRACT The paper presents a preliminary investigation of wastewater quality in screen printing facilities in Novi Sad. The experimental research includes two selected parameters: pH value and BOD. The measured pH values were in the range of maximum allowed values, but very high BOD values indicate dominant organic pollution. Determined BOD values of collected samples were in the range from 36 – 206 mg/l. These BOD values show great organic pollution of wastewater from screen printing facilities with biodegradable organic matter. INTRODUCTION Screen printing (SP) is one of five common printing processes. Screen printing is considered to be the most versatile of the printing processes and is applicable to a wide range of substrate materials, including textiles, plastics, papers, fabrics, wood, leather, glass, metals and ceramics. SP is also used to manufacture electronic printed circuit boards. It is used for specialty printing such as T-shirts, posters, banners, decals, and wallpapers. This type of printing process makes up a small but growing segment of the printing industry. The advantage of screen printing over other printing processes is that the press can print on substrates of any shape, thickness and size. SP is differs from other printing processes in that stencils and screens, rather than plates, are used to transfer the image. A significant characteristic of screen printing is that a micro thickness of the ink can be applied to the substrate. Because of the simplicity of the application process, a wide range of inks and dyes are available for use in screen printing. Cleaning or reclaiming screens in the screen printing process generates the specific wastewater. Screen printing facilities deal with many hazardous substances that can effect and contaminate air and water, indoor and outdoor. The major chemicals used in SP include screen emulsions, inks, and solvents, surfactants, caustics and oxidizers. As there is a lack of data on the characteristics of wastewater from this type of printing facility in Serbia, the experimental research was conducted. The preliminary experimental work includes determination of two selected parameters, i.e. pH value and BOD. Wastewater from screen printing plants was investigated in accredited Laboratory for monitoring of landfills, wastewater and air within the Faculty of Technical Sciences, University of Novi Sad. This kind of research has been conducted for the first time in the city of Novi Sad, focusing on the wastewater of the screen printing industry. Screen Printing Process Overview Screen printing consists of five processes: image processing, stencil and screen preparation, printing, finishing, and screen reclamation, and each of them can be identified as part of the prepress, press, or post-press steps. Primary waste streams of concern in a screen printing facility include the various hazardous compounds found in used photo processing solutions and VOC emissions resulting from the use of inks and cleaning solvents (Table 1).

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Table 1. Screen Printing: Waste Streams of Concern (adapted from Washington State Department of Ecology, Environmental Management, and Pollution Prevention: A Guide for Screen Printers, 1994 [1]) Waste stream Area of Concern Environmental Concern Hazardous Waste Air "Listed" chemicals1 Aerosol Cans Quality VOCs Hazardous Waste Developer Hydroquinone Wastewater Hazardous Waste Fixer High silver Wastewater Hazardous Waste High pH value Haze Remover Wastewater "Listed" chemicals2 Hazardous Waste Air "Listed" chemicals VOCs Ink Remover Quality Heavy metals3 Emulsion Remover Wastewater High pH Reactivity Parts Washer Solvent Hazardous Waste "Listed" chemicals Hazardous Waste Air "Listed" chemicals2 Screen Degreaser Quality VOCs Waste Screen Emulsion Wastewater Suspended Solids Hazardous Waste Air Improper disposal of inks Shop Towels Quality and solvents Hazardous Waste Air "Listed" chemicals VOCs Waste Ink Quality Heavy metals3 1

Listed chemicals include the following chemicals: acetone, methanol, benzene, methylene chloride, carbon tetrachloride, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), chlorobenzene, n-butyl alcohol, cyclohexanone, 2-nitropropane, 2-ethosyethanol, ethyl ether, isobutanol, etc. 2

Formulations for haze remover and screen degreaser that do not contain listed chemicals are now readily available. 3

Conventional, solvent-based ink systems are more likely to contain some amounts of heavy metals such as barium, cadmium, chromium, or lead.

Hazard chemicals which emerge wastewater of SP Metals which could be classified as the emerging contaminants are found in some ink pigments and can end up in wastewater [2]. Solvents are used to clean and reclaim screens and are present in some inks [3]. Significant levels of organic solvents can been found in the wastewater samples from screen printers. Volatile solvents that vaporize readily into the air may pose health and safety hazards to employers in plants [4]. Cleaning solvent alternatives are available but may not present less environmental risk therefore they are synthesized chemicals. Effluent requirements for direct discharge are shown in Table 2. Table 2. Effluent requirements for direct discharge according to US EPA [5] Parameter Maximum allowed value pH value 6,5 - 10 BOD (mg/l) 30 COD (mg/l) 150 Cadmium (ppm) 0,1 Total Chromium (ppm) 0,5 Zinc (ppm) 2

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MATERIALS and METHODS In order to conduct the pilot pre-investigation on the wastewater from screen printing facility in Novi Sad, Vojvodina Region, 6 samples of wastewater after washing the screens, from XY screen printing plant in Novi Sad, were taken. The wastewater of SP was directly discharged in the sewage system and represents the serious source of contamination of air, water, biota and humans in biosystems. Measuring of pH value was performed in situ with a portable Multi 340i WISSENSCHAFTLICH-TECHNISCHE WERKSTATTEN GMBH device. The samples for determination of BOD were collected in sealed 1 litter sample containers, transported to the laboratory in hand refrigerator and analyzed immediately. Biological oxygen demand (BOD5) was determined using HACH BOD TRAK device. The sample is kept in a sealed container fitted with a pressure sensor. According to manufacturer specifications, lithium hydroxide is added in the container above the sample level as a substance which absorbs carbon dioxide. Oxygen is consumed and, as ammonia oxidation is inhibited, carbon dioxide is released. The total amount of gas, and thus the pressure, decreases because carbon dioxide is absorbed. From the drop of pressure, the sensor electronics computes and displays the consumed quantity of oxygen.

Figure 1. Measuring of BOD parameter using HACH BOD TRAK device

RESULTS The results for pH value and BOD of 6 wastewater samples (S 1, S 2, S 3, S 4, S 5 and S 6) from SP facility, obtained in the Laboratory for monitoring of landfills, wastewater and air within the Department of Environmental Engineering and Occupational Safety and Health, Faculty of Technical Sciences, University of Novi Sad, are presented in Table 3.

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Parameter pH value BOD [mg/l]

Table 3. The results of wastewater samples S1 S2 S3 S4 S5 7,2 7,4 6,3 6,1 6,8 38 36 206 58 46

S6 6,1 102

The measurement data in Table 3 show that the pH values of each sample from screen printing facility in Novi Sad are in the range of maximum allowed values (Table 2) [6]. Regarding obtained results for BOD values it can be concluded that each sample of wastewater exceeded the maximum allowed values for effluent requirements (Table 2). Determined BOD values for collected samples were in the range from 36 – 206 mg/l. These values of BOD show great organic pollution of wastewater from screen printing facility with biodegradable organic matter. Discharging of wastewater in the sewage system may present several risks to human health and the environment. The research activities are the part within the National project No.34014 financial supported by Ministry of Science and Technological Development of Serbia. CONCLUSIONS Evaluation of this experimental study indicated poor water quality of samples collected from screen printing facility in Novi Sad. On the preliminary results it could be concluded the serious contamination by organic matter and high risk to the whole environment and biosystem. The BOD values as the characteristic parameter of the biochemical and chemical status of wastewater shows dominant organic pollution from SP facility loaded by organic matter. Two values of Sample 3 (206 mg/l) and Sample 6 (102 mg/l) illuminate the high content of organic matter and imperatively require treatment before discharging into sewage system and continuous monitoring activities. The measured pH values are in the range of maximum allowed values, but very high BOD values indicate dominant organic pollution. ACKNOWLEDGMENT This research was supported by Ministry of Education and Science, Republic of Serbia within the Project No. 34014. REFERENCES [1] Washington State Department of Ecology, Environmental Management, and Pollution Prevention: A Guide for Screen Printers (1994) [2] Vojinović - Miloradov, M., Kiurski, J., Emerging substances of concern in the graphical industry, 5th International GRID Symposium, Novi Sad November 11-12 2010, Faculty of Technical Sciences, pp. 191-200, ISBN 978-86-7892-294-7 [3] Kiurski J., Krstić, J., Oros, I., Adamović, S., Vojinović - Miloradov, M.: Waste printing inks as a pollutant of graphic environment, 5th International GRID Symposium, Novi Sad November 11-12, 2010, Faculty of Technical Sciences, 207-210 , ISBN 978-86-7892-294-7 [4] Kiurski J., Vojinović-Miloradov M., Đogo M., Adamović D., Milovanović D., Risk Assessment of BTEX and Ozone in Printing Industry in Novi Sad , 9. European Meeting on Environmental Chemistry (EMEC9), Girona: University of Girona, 3-6 Decembar, 2008, 98-98 [5] Effluent Limitation Guidelines US EPA (2011) [6] Environmental regulations and best management practices. Printing operations in the capital regional district. (May 2003)

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POTENTIAL ADVERSE EFFECT OF ENDOCRINE DISRUPTORS AT LOW DOSES Milena Stošić1*, Sanja Veselić2, Branko Vidicki3 1 Faculty of Technical Sciences, Department of Environmental Engineering, University of Novi Sad, Serbia 2 Faculty of Natural Sciences, Department of Biology and Ecology, University of Novi Sad, Serbia 3 Faculty of Agriculture, University of Novi Sad, Serbia * e-mail: MILENA.STOSIC@GMAIL.COM ABSTRACT Chemical pollution, acute and chronic, can present a serious threat to living organisms, their health, and their biodiversity. Intensive use of pesticides has resulted in their presence in water, soil and air. Number of these chemicals can act as endocrine disrupting compounds, cause pollution of natural ecosystems and can adversely affect species diversity. Endocrine disrupting chemicals are emerging risk for human health and the environment. What makes endocrine disruptors so significant is that they are often more active at lower doses, far beneath of those which are traditional concern to toxicologists. INTRODUCTION The very important question of today’s life is regarding organic chemicals used in pesticides and if they are putting people and wildlife in risk by interfering with their endocrine system. It is possible to detect the presence of measurable levels of several hundred synthetic chemicals in every living person. Those contaminants didn’t exist prior to 20th century, but even though we are living in 21th century, we are still ignorant about the health impacts and interactions of most of these compounds. Endocrine disrupting chemicals (EDC) are emerging risk for human health and the environment. Endocrine disruption is a relatively unstudied area in toxicology and is only recently being taken into account in risk assessment [1]. Unlike carcinogens and other toxins, government agencies were not designed to regulate EDCs, which are much more complicated and difficult to understand [2]. EDCs are toxic because they disrupt the normal function of the endocrine system. By interacting with hormone receptors, they prevent endogenous hormones to bind with them and induce biological effect. Standard tests used by the EPA to evaluate reproductive and developmental toxicity often fail to consider the impact of doses lower than those producing no evidence of overt adverse effects, described as the no-observed-effect level, or NOEL. Some endocrine disruptors exhibit dose-response relationships described as nonmonotonic, meaning that within a certain dose range, a chemical's effects on a given end point actually become greater as the dose is reduced [3]. The endocrine system involves a myriad of chemical messengers and feedback loops. Often, the endocrine system does not respond to chemicals in accordance with the canons of traditional toxicology. In toxicological studies, the failure to apply fundamental principles of hormone receptor biology to dose selection can potentially lead to a huge error in estimating risk associated with exposure to doses below the

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NOEL determined in traditional toxicology studies [1]. These issues are problematic for toxicology because they challenge the traditional use of extrapolation from high-dose testing to predict responses at much lower environmentally relevant doses. Additionally, these data also provide evidence that some traditional assumptions used in risk assessment for systemic (noncancerogenic) toxicants, such as the assumption of threshold and monotonic doseresponse relationship can not be uniformly applied to EDCs [1]. It is very important to understand the link between sources of pollutants and health effects. Chemical pollution, acute and chronic, can present a serious threat to living organisms, their health, and therefore, their biodiversity. There exists little doubt that the biological diversity is being rapidly depleted as a direct and indirect consequence of human actions. Intensive use of conventional pesticides, as well as the presence of variety of manufactured products in wide usage including plasticizers, flame retardants, and various industrial chemicals, can lead to biodiversity decline. Since endocrine disruptors are emerging risk for environment, wildlife, and human health, manny of these chemicals are classified as emerging substances of concern by NORMAN project [4]. LOW DOSES NON-LINEAR RESPONSE CURVES What makes endocrine disruptors so significant is that they are not bound by the classic assumption that by lowering the dose, we decrease the toxic potential of the chemical. The threshold-based system of determining chemical toxicity, used in regulations and industry, is simply not capable of protecting from endocrine disrupting chemicals [5]. The relationship between low doses and risk may not always be linear. Major errors in assessing risk can be made when linearity of response and the preceding receptor occupancy is assumed across the entire dose range, which is the current assumption used in risk assessment [1]. Government Agencies often find crafting the proper regulations difficult, given the fact that most toxins, including EDCs follow a U- or J-shaped curve, depending on whether the substance causes a decrease in risk or an increase (Fig.1.) [6]. Toxicologists now believe that exposure to toxins at very low or very high levels has more adverse affects on homeostasis then mid-level exposure rates [2]. This combination of low-dose stimulation followed by high-dose inhibition is commonly termed “hormesis”. Hormesis is not new concept, and it has been in use for long time by those studying epidemiology and molecular pharmacology, but it was ignored by toxicology community until relatively recently [6]. Hormetic effects are difficult to measure and quantify without extensive studies using many animals, and are not frequently seen in experiments designed by toxicologists who are more interested in upper end of dose response curves, where dose and risk are at their highest [6]. There are some strong advocates of the U-shaped dose-response curve who think that there should be a paradigm shift in toxicology [7, 8]. The old paradigm focused on acute toxicity. The new paradigm recognizes that there are other ways that contamination can work [9]. The implications of this new paradigm are profound. Toxicologists used to believe that background levels, levels experienced by most people, the levels that are unavoidable living in the world today, were safe. That assumption of safety was allowed because scientists were considering them under the old paradigm [2]. Endocrine system is complex, and regulation of EDCs can become complicated because lowering the exposure levels may, in fact, increase the health and environmental risks. Additionally, reaction to unequal concentration levels may be different in different stages of development [2].

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Fig. 1. Dose–response relationships (12) The toxicological approach involves dose-selection based on the maximum tolerated dose, which can be described as “top-down dose selection”, whereas the physiologic approach used by Nagel et al. (1997) [10] can be described as “bottom-up dose selection” [11]. Vom Saal and Hudges (2005) [11] showed that there is now overwhelming evidence demonstrating that different experimental approaches lead to very different conclusions of safety regarding the reference dose for Bisphenol-A of 50 µg/kg/day. Findings based on low dose studies thus present a strong challenge to the assumption that form the basis for chemical risk assessments [11]. CONCLUSION •





Endocrine system is very complicated and it is becoming more and more obvious that traditional toxicology assumption that dose - response curves are always monotonic can not apply anymore. High doses can, sometimes, block effects that occur at lower levels. This is very common with endocrine disrupting chemicals, which is why the dose - response curves for EDCs are not linear. It is an imperative for policymakers and agencies to deal with the toxicology implications of new and complex chemicals. Techniques used to deal with toxic chemicals are inadequate and will be more and more inappropriate when more chemicals are discovered to have endocrine disruption effect. Low doses of hazard chemicals in level of ppb and ppt are registered to have negative effect on biodiversity and changing environment. Low doses effect may be explained by presence of free molecules, not associated in clusters, but with free active center and therefore with maximal activity.

REFERENCES [1] Welshons, W., Thayer, K., Judy, B., Taylor, J., Curran, E., vom Saal, F. (2003). Large effects from Small Exposures. I. Mechanisms for Endocrine Disrupting Chemicals with Estrogenic Activity. Environ Health Perspect, 111, p. 994-1006.

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[2] Gitanjali, D. (2005). Endocrine Disruptors: A Case Study on Atrazine. Temp. J. Sci. Tech. & Envtl. L., p. 397-418. [3] Schmidt, C. (2001). The low-down on low dose endocrine disruptors - NIEH news. Environ Health Perspect, 109, p. 420-421. [4] http://www.norman-network.net/index_php.php [5] Pullin, A. (2002). Conservation Biology, Cambridge University Press, Cambridge. [6] Hadley, C. (2003). What doesn’t kill you makes you stronger. European Molecular Biology Organization, 4, p. 924-926. [7] Calabrese E., Baldwin, L. (2003). Hormesis: The Dose-response Revolution. Annu Rev Pharmacol Toxicol, 43, p. 175-197. [8] Krimsky, S. (2000). Hormonal Chaos. Johns Hopkins University Press. [9] http://www.ourstolenfuture.org/newscience/lowdose/lowdose.htm [10] Nagel, S., vom Saal, F., Thayer, K., Dhar, M., Boechler, M., Welshons, W. (1997). Relative binding affinity-serum modified access (RBA-SMA) assay predicts the relative in vivo bio-activity of the xenoestrogens bisphenol A and octylphenol. Environ Health Perspect, 105, p.70–76. [11] vom Saal, F., Hughes, C. (2005). An Extensive New Literature Concerning Low-Dose Effects of Bisphenol A Shows the Need for a New Risk Assessment. Environ Health Persp, 113, p. 926-933. [12] http://www6.ufrgs.br/favet/imunovet/molecular_immunology/generaltoxicology.html

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PSEUDO-PERSISTENT POLLUTANT IN THE ENVIRONMENT: EMERGING SUBSTANCES dr Mirjana Vojinović-Miloradov, dr Maja Turk Sekulić, dr Jelena Radonić, dr Ivan Spanic, dr Jelena Kiurski, MSc Dušan Milovanović, MSc Ivana Mihajlović University of Novi Sad, Faculty of Technical Sciences, Department of Environmental Engineering and Occupational Safety and Health Institute of Analytical Chemistry, FCHPT-STU, Bratislava, Slovakia miloradov@uns.ac.rs

ABSTRACT In the recent time, considerable interest has grown concerning the presence of the emerging substances, EmS. These are contaminants that have been recently detected in the environment due to their long-term, pseudo-persistent and increased use. Most of EmS are wide spread and applied in different fields using as pharmaceuticals, for both human and animal uses, household chemicals, personal care products, nanomaterial, anticorrosive and agriculture chemicals and others. European legislation did not regulate the status and the maximum allowed concentration of most EmS. EmS might jeopardize surface water and ground water resources, particularly, drinking water production. The preliminary results of Danube surface water in vicinity of Novi Sad show presence of benzotriasole and caffeine. These newly recognized contaminants represent a shift in traditional thinking of protection scenario and eco status of environment and water bodies. Keywords: emerging substances, pseudo-persistent, surface and ground water INTRODUCTION Chemicals are a part of modern life and are present in all spheres of human life. They are used as pharmaceuticals, pesticides, detergents, fertilizers, dyes, paints, finish, preservatives, food additives, anticorrosive materials among others. The biggest number of organic and inorganic chemicals belongs to so called emerging chemicals. They contribute to our well being, high life expectancy and economic prosperity. As new chemicals are introduced or others find new applications, and analytical methods improve, the occurrence of previously undetected chemicals, termed “emerging substances”, EmS in surface ground water, drinking water is frequently noticed. EmS include global organic and some inorganic substances, such as flame retardants, pharmaceuticals, personal care products, endocrine-modulating chemicals, nanoparticles and biological metabolites. It is almost inevitable that very small amounts of these substances, which are manufactured to protect human health, improve consumer goods, or optimize agricultural production, are unintentionally released into the environment. Recent improvements in sophisticated analytical methods have enabled the identification and quantification of these substances, in very low concentrations (ppb, ppt), which likely have been present in waters for decades.

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In Europe, millions of people depend on river surface waters (Danube, Meuse, Rhine) as the sources of drinking water. Surface waters are contaminated with thousands of chemical compounds originating from industry, agriculture, household use which number is still increasing. Therefore the presence of EmS residues in the environmental mediums has become a subject of growing concern in the past decade. Project NORMAN identified a list of the currently most frequently discussed EmS today [2]. According to NORMAN EmS can be defined as substances that have been detected in the environment, but which are currently not included in routine monitoring programs in EU and whose fate, behavior and (eco) toxicological effects are not well understood. Within NORMAN EmS are divided into 23 categories (classes) with 79 subcategories/subclasses with examples of individual emerging substances more than 700, whose list is still open. Some portion of EmS will enter wastewater as part of the influent. Unless specifically removed by wastewater treatment processes, they may persist and be released into receiving waters as trace pollutants. Some fraction of the organic compounds used for agricultural purposes will runoff into a surface water body, while another fraction of the compounds will infiltrate and reach the groundwater system. The term trace pollutant indicates very low concentrations of an environmental contaminant in the μg L−1 range or lower which is one of the basic properties of EmS. It is believed that long-term consumption of EmS can cause adverse health effects in most organisms at concentrations as low as a few ng L−1. Predicting the human health effects caused by exposure to EmS is a difficult task [3]. The objectives of this paper are to provide an overview on the residues of EmS in freshwater, in order to prioritize further EmS research needs. CLASSIFICATION OF EMERGING SUBSTANCES Most of EmS have been present in the environment for a long time, but their significance and finding are only now being elucidated and, therefore, they are generally not included in the legislation. EmS can be classified under this category according to their chemical class (chemicals of totally new structure), type of use (new uses in industry or in consumer realms), type of effect (new discovered effects), source (new or previously unknown origins for existing chemicals), and exposure (pathways that had not been anticipated or had been previously discounted as not possible). Taking into account these criteria, compounds that can be considered as EmS are the pharmaceuticals and personal care products (PPCPs), steroids, xenoestrogens and other endocrine disrupting compounds (EDCs), methyl tert-butyl ether (MTBE) and related compounds, surfactants and their metabolites (alkylphenolic compounds, linear alkylbenzenesulfonate (LAS) and sulfophenyl carboxylates (SPC)), drinking water disinfection by-products (DBPs) including N-nitroso-dimethylamine (NDMA) and nitrosamines, gasoline additives, brominated flame retardants (polybrominated diphenyl ethers), industrial additives and agents, algal toxins, and other pathogens, organotins, perfluorooctanoic acid (PFOA) and perflluorooctanesulfonate (PFOS), pesticide degradation products, chiral contaminants, chemical warfare agents, and a variety of miscellaneous chemicals such as caffeine, cholesterol, etc. Exposure to EmS in the aquatic ecosystem is of particular concern, since aquatic organisms are subjected to continual impact of EmS. This fact makes EmS, even those that some of them have relatively short environmental half-lives, to be assumed as pseudo-persistent. Moreover, the polar and non-volatile nature of some EmS prevents their escape from the aquatic realm. Pharmaceuticals. The possibility of emission of pharmaceuticals in the environment has been recognized in environmental science since several decades. Conventional municipal sewage

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treatment plants appeared to play an important role in the introduction of pharmaceuticals in the environment purifying household waste water mainly by subsequent application of bacterial degradation of organic matter, and coagulation/flocculation for the removal of suspended solids and phosphates. In these processes, which are predominantly optimized for the degradation of waste of natural origin, organic contaminants are primarily removed by bacterial degradation and sorption to solids. The past decades have shown that this treatment is rather inadequate in removing pharmaceuticals in effluents and receiving waters in their original form, or as degradation products. Besides household sewage, other emission sources of human pharmaceuticals are waste waters from manufacturers, hospitals, and disposal of unconsumed drugs via solid waste. It is estimated that up to 65% of sold pharmaceuticals are never consumed. Furthermore, large quantities of pharmaceuticals, e.g. antibiotics and inflammatory drugs do not pass sewage treatment. Several studies have reported that some pharmaceuticals are not completely removed by drinking water treatment and are found at trace levels in drinking water [3]. It was demonstrated that the environment is also contaminated with drugs with predominantly non-medical applications. It is estimated that up to 5% of the world population uses illicit drugs, like cocaine, heroin, cannabinoids (hashish, marijuana), and amphetaminelike stimulants (such as ecstasy). In 2005, Zuccato et al. published a first systematic study on the presence of cocaine and its degradation product benzoylecgonine in surface and waste water samples from the Italian river Po. The results were interesting not only from an environmental but also from a societal-forensic point of view. Based on the measured concentrations, the authors calculated that cocaine consumption was considerably higher than estimated. Also non-controlled stimulatory compounds, such as caffeine from coffee, tea, and soft drinks and nicotine from tobacco were often included in these investigations. Illicit and non-controlled drugs were structurally found at ng/L or lower concentrations in waste and surface waters. Degradation in sewage treatment plants varied considerably between different drugs. Personal care products, PCPs comprise active ingredients of cosmetics, toiletries, and fragrances. They are applied as preservative or to alter odor, appearance, touch, or taste. One group of PCPs consists of compounds used as fragrance, such as polycylic musks. A second group comprises preservatives like parabenes applied in shampoos, creams, and toiletries to prevent bacterial decay. Disinfectants like triclosan and clorophene are used on a large scale. Triclosan for example has been used for decades in a wide variety of consumer products, ranging from toothpaste and hand soap to toys and socks. Compounds such as benzophenone in sun screen lotions that block UV light have gained interest of environmental chemists and biologists. Alkylated siloxanes are compounds used in soaps, hair-care products, etc. PCPs enter the environment via sewage treatment effluent as a result of showering, washing off, washing clothes, etc., but are also directly released in surface waters by recreational activities as swimming and sunbathing [5]. PCPs are observed regularly in effluents and surface waters worldwide. Some of them can accumulate in exposed organisms. Some personal care products are suspected to have potentially adverse potencies, such as estrogenic hormone-like activity (UV blockers, parabens), developmental toxicity (UV blockers), and extreme bioaccumulation (musks). Nanoparticles - constitute a rapidly growing research area. They are extremely small in size with diameters between 1 and 100 nm and have properties that differ from smaller (molecules) or larger (bulk materials) particles of the same composition. Besides inorganic compounds, such as TiO2 and nanosilver, and also organic compounds, such as carbon nanotubes and ‘‘nano-C60’’, fullerene, are examples of nanoparticles. They can be of natural origin as well as manufactured and a wide variety of applications is foreseen or already implemented (in medicine and food industries). Meanwhile, questions about their

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environmental fate and possible human-health risks arise. Due to their small size, their surface is relatively large and their chemical reactivity and biological activity remain relatively high. Nanoparticles can enter the body and cells more easily than larger particles. It is suggested that they might evoke inflammatory responses and DNA damage. However, very little is as yet known about possible toxic properties of nanoparticles. Although currently environmental data are scarce, techniques for the analysis of nanoparticles in environmental samples are developing fast, and it is expected that monitoring data will become available soon. Flame retardants, FR are a class of chemicals that are widely used in plastics, textiles, furnishing foams, sofas, computers, televisions and other contemporary products, to slow down inflammation in the event of a fire and reduction of fire risks. In the past, mainly polybrominated biphenyl and polybrominated diphenyl ethers were used for this purpose. These compounds are structurally similar to ‘‘conventional’’ contaminants as polychlorinated biphenyls, and likewise is their behavior in the environment. Brominated FRs are structurally detected in tissues, blood and breast milk of wildlife and humans. This is worrying, that these compounds and their degradation products have several potentially toxic properties, such as the ability to disrupt the thyroid, androgenic and estrogenic hormone systems (Legler 2008), toxicity for the nervous system and they might also be carcinogenic. Because of their low solubility in water, they tend to sorb to sediments in rivers (Rahman et al. 2001) instead of reaching high concentrations in water. Another class of FRs are organophosphate FR with tributylphosphate and tris(2-chloroethyl)phosphate as important representatives. Their widespread use may even increase since many brominated FR have been banned. Organophosphate FR, for which toxicity data still are scarce, are persistent, although better soluble in water than brominated ones, and several studies have reported their presence in surface and waste waters. ANALYTICAL DETERMINATION OF EMS For most of the EmS there are lack of environmental data, basically because they are not, or have not been, determined and regulated in the environment. Another reason for this is the shortage of sophisticated analytical methods and equipment for proper monitoring of waste and for a risk assessment of surface and groundwater quality. At the beginning the analysis of organic EmS has been performed by high performance liquid chromatography coupled to ultraviolet detection (HPLC–UV) and gas chromatography (GC) coupled to flame ionization detection (GC–FID), electron capture detection (GC–ECD) and mass spectrometry (GC–MS). However, after the introduction of atmospheric pressure ionization, liquid-chromatography coupled to mass spectrometry (LC–MS) has largely replaced GC methods. In the particular case of emerging pollutants, for most compound classes, LC–MS and especially UPLC (TOF) MS2 which provides additional selectivity and sensitivity, has become the technique of choice. Although the use of MS, and especially MS–MS, allows increasing sensitivity, an analyte preconcentration procedure is almost always necessary to reach limits of detection low enough to determine the ultra trace levels, within the ng/L or lower range at which EmS, are present in the environment. For this purpose, solid phase extraction (SPE) is the most widely used preconcentration procedure as well as to remove interfering components from the matrix [1]. Improved analytical methods have resulted in the identification of many more chemicals in ambient waters or the tissues of organisms than were previously believed to occur. Considering the current information on EmS, those with the highest propensity for adverse

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biological effects include those that are persistent and pseudo-persistent, bioaccumulative, carcinogenic, lipophilic, toxic, endocrine disruptors, and/or sized in the nanoscale range. Persistence may be caused by the structural stability of the chemical (e.g., a long half-life) or it may be a result of constant loading to the environment - pseudo-persistent. Even if there is some degree of degradation, the parent compounds will nevertheless be present at constant levels in the environment if the input rate is higher than their rate of degradation or mineralization. This can be called second order persistency or pseudo persistency, Vinput > Vdegradation. Persistency is one of the most important criteria in the environmental assessment of chemicals. Pseudopersistent, lipophilic, bioaccumulative, endocrine-disrupting compounds that may also be carcinogenic should therefore be the highest priority for regulatory control and risk assessment. Recent research suggests that some nanomaterial also possess many of these high-risk properties [3]. INSTEAD OF CONCLUSION Rapid improvements in chemical analysis techniques (HPLC-TOF-MS2) during the last decades have led to the discovery of myriads of EmS in surface waters at very low concentrations (ppb and ppt), that could not be observed earlier. EmS can pass intact through conventional sewage treatment facilities, into waterways and even aquifers posing a threat to underlying. The presence of EmS in very low doses, their pseudopersistancy, no regulations for their maximal allowed concentration, unknown negative effect on environment, biota and human beings, generated the new shift in traditional approach and thinking within the environmental protection’s scenario. This new approach focused on EmS requires holistic joint efforts of the scientific community and water sector. Our preliminary results of Danube surface water show presence of benzotriasole and caffeine. This is the first research of this kind done in Danube surface water near Novi Sad and is part of the national and ino projects. ACKNOWLEDGEMENT This research was supported by Ministry of Education and Science, Republic of Serbia (III46009) and Program Science for Peace and Security (NATO), Project No 984087. LIST OF REFERENCES 1. Houtman, C.J.: Emerging contaminants in surface waters and their relevance for the production of drinking water in Europe, Journal of Integrative Environmental Sciences 7, 271-195, 2010. 2. NORMAN FP6 network laboratories monitoring emerging pollutants http://www.normannetwork.net 3. Murray, K.E., Thomas, S.M., Bodour, A.A.: Prioritizing research for trace pollutants and emerging contaminants in the freshwater environment, Environmental Pollution 158, 3462-3471, 2010 4. Vojinović Miloradov, M. et al.: Emerging substances of concern and their ocurrance in surface water and groundwater, The International Conference Engineering of Environment Protection – TOP2011, June 2011, Bratislava, Slovak Republic. Proceedings, ISBN 978-80-227-3519-3, pp. 277-288.

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ÚTBURKOLATOK ÖSSZGAMMA-SUGÁRZÁSÁNAK VIZSGÁLATA Sós Katalin SZTE JUHÁSZ GYULA PEDAGÓGUSKÉPZŐ KAR ÁLTALÁNOS ÉS KÖRNYEZETFIZIKAI TANSZÉK H-6725 Szeged, Boldogasszony sgt. 6. soska@jgypk.u-szeged.hu ABSTRACT The world average of radioactive background radiation is 2.4 mSv pro year. The main part of this background radiation is come from builded environment. From this reason many international project was focused on the radioctive radiation of the building materials. However the radiation from pavemant materials has been less researched. Therefore our departement feel it important to adress more reseach of radiation of different type of pavement and layers of pavement. The ND-497 type portable scintillation detector was used for our measurements. During our measurements the radiation of pavement surface and the layers of pavement was measured directly. The results of our project was that the radioactive radiation over pavement was driven by the materials porosity and the type of this materials similar to the building materials. It is beacuse in case of low porosity the radon - comes from earth and pavement - diffusion was blocked. It means that the pavements are decrease the radiation compare to the base soil results from low radioactivity of concrete and high porosity of pavement. In case of asphalt the situation is a bit complicated. The dose is decreasing over the sidewalk but increase over the roadway compare the base soil. In this case we have to remember that the asphalt are build over the concrete base. Finally the ratio of this two layer will define the final radiaoctive radiation. BEVEZETÉS A természetes radioaktív sugárzás 60-75%-a az épített környezetünkből adódik, ezért nagyon fontos, hogy felmérjük és ismerjük a különféle építőanyagoktól és építési technikáktól származó radioaktivitás mértékét. Az építőanyagok radioaktivitása elsősorban az alapanyagául szolgáló nyersanyag radioaktívelem-tartalmától függ. Emellett azonban a fizikai jellemzők is meghatározóak, főleg azok, amelyek hatással vannak a radon diffúziójára. A radon az urán és a tórium bomlásából származó, alfa-sugárzó nemesgáz, amelynek a leányelemei is radioaktívak. Egyes számítások szerint a háttérsugárzás kb. fele a radonnak tulajdonítható, és a radon nagy része szintén az építőanyagokból, pontosabban azok urán- és tóriumtartalmából származik. Ha az építőanyag porózus szerkezetű, és ezek a pórusok összefüggő „csatornarendszert” alkotnak, a radon könnyen kidiffundál az anyagból; emiatt magának az anyagnak a radioaktivitása lecsökken. Ha azonban tömör, vagy zárt pórusú az anyag, a radon bennreked, és a felhalmozódó leányelemei következtében az anyag magasabb radioaktivitást mutat (Tóth, 1983., Keller, 2001.). Az építőanyagok radioaktivitására vonatkozóan tanszékünk is végzett méréseket, amelyek során 1-2 m magas építőanyaghalmok tetején mértük az összgamma-dózisteljesítményt. A fontosabb építőanyagokra kapott eredményeket az 1. táblázat mutatja be (Sós, 2007). Ezek a vizsgálatok a nemzetközi tapasztalattal megegyező eredményeket adtak: viszonylag magas aktivitásértékek adódtak pl. a különböző téglák esetében, ami a magas agyagtartalom következménye - az agyagnak ugyanis igen jelentős az urán- és a 40K-tartalma (Steiner és

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Várhegyi 1991). Alacsony aktivitásértéket mutatott viszont a pórusbeton falazóelem. Ennek fő összetevői a homok, a cement és/vagy a mész, továbbá finomszerkezetű, kovasavtartalmú anyagok, pórusképző adalékok. Ezeknek az anyagoknak kicsi a radioaktívelem-tartalmuk. Emellett a beton - és főleg a pórusbeton - nagy porozitása megakadályozza, hogy a radon és leányelemei felhalmozódjanak az anyagban, ez is hozzájárul az alacsony aktivitás kialakulásához. Ugyancsak alacsony aktivitás értékek adódtak méréseink során a sóder, a kavics, valamint a homok esetében. Ezek aktivitása azonban igen változó lehet, attól függően, milyen kőzet átalakulásából keletkeztek. A gránitos, vagy agyagos kőzetek aprózódási termékei ugyanis minden esetben magas aktivitást mutatnak. 1. táblázat. Építőanyagok összgamma-sugárzása Termék Dózisteljesítmény (nGy/h) Homok

2,2-39,0

Sóder

34,6-34,9

Különféle téglák

85,9-113,6

Pórusbeton falazóelem

44,7-49,3

Beton díszburkolat

36,6-36,9

MÉRÉSI MÓDSZER 2005 óta tanszékünk - hallgatóink bevonásával – többféle mérést is végzett az épített környezet radioaktivitására vonatkozóan. Többek között az útburkolatoktól származó radioaktivitást is mértük, ami egy eddig kevésbé vizsgált terület. A mérések során a felszíni összgamma-dózisteljesítményt határoztuk meg ND-497 típusú, hordozható szcintillációs detektorral, amely NaI(Tl) szcintillátor anyagú. Az energiatartományát 0,4-3,0 MeV közöttinek választottuk. Méréseinket közvetlenül az útburkolati réteg felett végeztük el, ekkor a kapott beütésszám 90%-a származik a vizsgált anyagtól. A mérések időpontját úgy választottuk meg, hogy azok a külső paraméterek, amelyek jelentősen befolyásolják a radonmozgást - mint pl. a légnyomás, a hőmérséklet, a szélviszonyok -, minden esetben lehetőleg azonosak legyenek. Az útburkolatoktól származó aktivitást több tényező is meghatározza: - az alaptalaj radioaktivitása, - az útburkolat sugárzásárnyékoló és radonszigetelő hatása, - az útburkolattól származó sugárzás, - valamint az épített környezet hatása. EREDMÉNYEK Szeged Petőfi telep városrészben - csatornázási munkálatokat követően – a különböző útépítési fázisokban külön-külön is megvizsgálhattuk a burkolatrétegek aktivitását: a földmű, az útalap, a kész aszfalt és betonburkolat, valamint az eredeti altalaj felett mérhető sugárzást. A mérésnél igyekeztünk minél több, közel azonos építési fázisban lévő mérési pontot felvenni, maximum 5 méteres távolságon belül. A területen végeztünk méréseket az útfelbontás előtt és után is; ezzel az is megállapítható, hogyan hat a burkolat és útalap-csere a felszíni sugárzásra. Ezek a vizsgálatok azért is jelentősek, mert ily módon mutatható ki, hogyan befolyásolják az egyes rétegek az úttest felett mérhető sugárzást: milyen szerepe van az utak radioaktivitásában az útalap vagy a kopóréteg összetételének, tömörségének, porozitásának, stb.

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Ezen mérés során közel 300 mérési pontunk volt, itt csak néhány fontosabb mérési eredményt és megállapítást emelünk ki: - A homokfeltöltés aktivitása a vártnak megfelelően alacsony. - A csatornázás után stabilizátorként használt betonréteg felett kisebb sugárzás mérhető, mint az eredeti aszfaltburkolatú helyeken, vagy akár az eredeti alaptalajnál, a beton kis aktivitásának és nagy porozitásának köszönhetően. - A csatornázás során visszatöltött talaj sugárzása valamivel nagyobb, mint az eredeti talaj sugárzása. A talaj a radioaktív anyagok eloszlása szempontjából ugyanis nem teljesen homogén, és a kivett talaj szerkezete is jelentősen megváltozhat: a kiásás során lazább lesz a talaj, a visszahelyezéskor tömörödik. Emellett az is ismert tény, hogy a csapadékkal a talaj mélyebb rétegeibe jutnak be a szennyezőanyagok, így a bemosódó radioaktív izotópok is. - Az aszfaltburkolattal ellátott útszakaszokon a sugárzás mértéke nagyobb volt, mint az alaptalajé. Az itt kapott adatok tehát azt igazolják, hogy az aszfalt útburkolat nem csak árnyékolja a talajsugárzást, de saját aktivitásából és nagy radonszigetelő-hatásából adódóan növeli is a felületi radioaktivitást. Ez a tény az aszfalt összetételének és szerkezetének ismeretében nem meglepő. Az aszfalt kötőanyaga a bitumen, ami a kőolaj legutolsó lepárlási terméke. A kőolaj környezetében az urán könnyen kicsapódik a mélységi vizekből, emiatt a kőolajban némi urán felgyülemlik. Nagy tömegéből adódóan az urán a legutolsó párlatban, azaz a bitumenben jelenik meg. Az aszfalt burkolatot emellett a nagyon kicsi porozitás jellemzi, kb. 3-4% a hézagtérfogata, emiatt a radon és leányelemei beszorulnak az aszfaltrétegbe, illetve az útalapból származó radon az aszfaltréteg alá. Ezt a radonszigetelőhatást növeli még a kopóréteg is, mely egy bitumenfelesleggel rendelkező, gyakorlatilag pórusmentes réteg. 2. táblázat. Az egyes burkolatrétegek összgamma-dózisteljesítménye Anyag

Megjegyzés

Átlagérték Szórás (nGy/h) (nGy/h)

Alaptalaj

eredeti talaj

58,9

4,8

Törmelékes talaj

csatornázás után feltöltve

65,9

3,0

Homok

csatornázás után feltöltve

51,5

2,2

Beton

15 cm vastag betonalap

51,8

3,1

Aszfaltút, új

15 cm aszfaltburkolat

70,6

3,2

Aszfaltút

fel nem bontott, eredeti aszfalt

75,8

2,5

Aszfalt járda

eredeti

53,6

6,3

Méréseink szerint az aszfaltjárdán valamivel kisebb aktivitás mérhető, mint az eredeti alaptalajnál, ami ellentmond az aszfaltburkolatnál leírtaknak. Ha figyelembe vesszük, hogy a járdánál a házfal közelsége miatt eleve nagyobb radioaktivitás várható, még inkább meglepő a lecsökkent dózis. Ez utóbbi ellentmondás magyarázatához részletesen kell elemeznünk az aszfalt járda és az aszfalt útburkolat szerkezetét. Az útburkolatot 15 cm vastag betonalap és ennél vastagabb, 18-20 cm-es aszfaltréteg jellemzi. Ezzel szemben a járdánál a betonalap a vastagabb, 10 cm-es, míg az aszfaltréteg csak 3 cm vastag (1. és 2. ábra). Ennek megfelelően az útburkolatnál inkább az aszfalt sugárzásnövelő hatása érvényesül, és kevésbé a beton kicsi aktivitása, míg a járdánál inkább a vastag betonréteg sugárzáscsökkentő hatása. Az aszfaltburkolatokról tehát nem jelenthető ki egyértelműen, hogy az növelné vagy csökkentené

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a talaj eredeti sugárzását, hiszen ez az útburkolat szerkezeti felépítésétől függ. Betonburkolat esetében viszont – akár járdáról, akár úttestről van szó – egyértelműen sugárzáscsökkenés várható. kopóréteg kötőréteg bitumenes felső alap stabilizált alsó alap

öntött aszfalt, homokkal és apró zúzott kővel K-20, kis töltőanyag-tartalmú aszfalt U-35, meleg bitumenes kavics B-100, betonalap

3 cm 4 cm 10 cm 15 cm

földmű, v. javítóréteg

90%-osan tömörített talaj

min. 50 cm

burkolat alap földmű

1. ábra. Aszfalt útburkolat rétegei járdaaszfalt betonalap földmű

öntött aszfalt, kevés töltőanyaggal, lágy bitumenből B-100 beton tömörített talaj

2-3 cm 10 cm 20-40 cm

2. ábra. Aszfaltjárda rétegei KÖVETKEZTETÉSEK: Méréseink alapján az alábbi, általános megállapítások tehetők: - Az útburkolatok akár jelentős mértékben is képesek megváltoztatni egy terület felületi gamma-dózisát, így a megfelelő útburkolatok háttérsugárzás-csökkentő eljárásként is alkalmazhatók. - A különböző útburkolatokat és útburkolati rétegeket összehasonlítva elmondható, hogy a homok- és a betonréteg csökkenti a talaj eredeti radioaktivitását (ha a homok nem rendelkezik nagy aktivitású alkotóval, pl. monacittal vagy cirkonnal). Az aszfaltréteg hatása viszont attól függ, hogy milyen a szerkezete, pontosabban milyen a betonalap és az aszfaltburkolat vastagságának aránya. Az épített környezet szerepe a radioaktív háttérsugárzásban, mint láttuk, igen jelentős. Ennek ellenére hazánkban még semmiféle szabályozás nincs az építőanyagok, vagy az épületek radioaktivitására vonatkozóan. Csupán egy európai uniós ajánlás létezik, amely az építőanyagok Ra, Th, és 40K-tartalma alapján határoz meg egy ún. aktivitáskoncentrációindexet (I). Ha ennek az értéke téglák esetén egynél, tetőcserepeknél hatnál kisebb, akkor az építőanyag radioaktivitás szempontjából megfelelő. C 226 Ra C 232Th C 40 K + + I= 300 Bq / kg 200 Bq / kg 3000 Bq / kg A magyarországi anyagokat 2006-ban az OSSKI megvizsgálta, és valamennyi mintát megfelelőnek találta. A törvényi szabályozás azonban ennek ellenére hiányzik. Csak bízhatunk abban, hogy ezek, és az ehhez hasonló mérések is hozzásegítenek bennünket ahhoz, hogy egyszer ezek a törvények és szabványok megszülessenek. IRODALOM - Köteles György: Sugáregészségtan, Medicina Könyvkiadó Rt. Budapest, 2002. - Tóth Árpád: A lakosság természetes sugárterhelése, Akadémiai Kiadó Bp., 1983. - Sós Katalin: Építőanyagok radioaktív sugárzása. Fizikai Szemle, 2007/3, 83-87. - G. Keller, B. Hoffmann, T. Feigenspan: Radon permeability and radon exhalation of building materials. / The science of the total environment, 2001. may /

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FORMALDEHYDE IN SCREEN PRINTING INDOOR Kiurski J., Adamović S., Oros I., Krstić J., Adamović D. University of Novi Sad, Faculty of Technical Sciences, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia E-mail: kiurski@uns.ac.rs ABSTRACT The presence of formaldehyde in air samples has been detected in five screen printing facilities in Novi Sad, Serbia. Air samples were sampled continuously during 4 hours, and concentration levels of formaldehyde was determined by UV-VIS spectrometry at 580 nm. The range of formaldehyde concentrations was from 0.413 to 0.836 ppm. Comparison of the detected concentration levels with the permissible exposure limit of 0.75 ppm (the OSHA standard) indicated that the formaldehyde concentration in facility 5 was 1.11 times higher than prescribed value. INTRODUCTION Formaldehyde is one of the most prevalent pollutants in indoor air. Industrial releases of formaldehyde can occur at any stage during the production, use, storage, transport, or disposal of products with residual formaldehyde. Formaldehyde have been emitted from chemical manufacturing plants, pulp and paper mills, forestry product plants, tire and rubber plants, petroleum refining and coal processing plants, textile mills, automotive manufacturing plants, and the metal products industry [1]. Screen printing is possibly the most versatile of all printing processes. It can be used to print on a wide variety of substrates, including paper, paperboard, plastics, textile, glass, metals fabrics, and many other materials [2]. Liquid materials (printing ink, cleaning solution, varnish, adhesive, etc.) used in screen printing process generate numerous toxic, hazardous substances of organic origin, especially contaminants from the group of volatile organic compounds (VOCs), such as formaldehyde, benzene, toluene, xylene, and methanol, are well known to enable the so-called buildingrelated sickness [3]. Depending on the type of used compound, the printing and drying processes, substrates and end-use application requirements, the amounts of formaldehyde are changed [4, 5]. Formaldehyde (CH2O) is a simple compound consisting of hydrogen, oxygen and carbon. It is also known as methyl aldehyde, methylene oxide, oxymethylene and oxomethane. It is a colorless gas with a pungent, irritating odor. It is a naturally occurring substance in the environment, but since the discovery and industrial processing of formaldehyde it has become one of the most common indoor air pollutants. It is highly reactive, readily undergoes polymerization, highly flammable and in air can form explosive mixtures. It decomposes at temperatures above 150 °C. Formaldehyde is readily soluble in water, alcohols and other polar solvents. It is harmful to human health, causing adverse respiratory effects and even cancer. Because of the toxicity, formaldehyde is classified as hazardous substances able to affect the workers' health [1, 3-5]. For this reason, extensive research has been conducted for the first time in Serbia on developing a continuous monitoring of the formaldehyde concentration levels in screen

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printing indoor. The objective was to determine the main emission sources of this hazardous pollutant in screen printing environment. MATERIALS and METHODS The air sampling was performed in five screen printing facilities (1-5) during manual printing process. Continuous sampling lasted for 4 hours. Air samples were collected using air sampler PRO-EKOS AT. 401X. The ambient air was infiltrated through the Drechsel bottles with diffuser frit containing absorption solution for formaldehyde (95 cm3 concentrated sulfuric acid and 0.5 cm3 1% hromotropic acid). Air flow was 0.5 dm3/min. Upon the sampling completion it was necessary to immediately determine the formaldehyde concentration, as the intensity of purple color of absorption solution is stable only a few hours. The absorption intensity was determined by UV-VIS spectrometry at 580 nm. The concentrations of formaldehyde were determined from the calibration curve using the standard formaldehyde solution of 1 mg/cm3 [6]. All used chemicals were of analytical reagent grade (Merck, Germany). The microclimate parameters were measured using instrument Mannix DLAF-8000 during the experiment. The values of temperature, relative humidity and light intensity of all printing facilities are presented in Table 1. Table 1 Values of microclimate parameters in screen printing facilities Microclimate parameters Screen printing t RH* LI** facilities [%] [lx] [°C] 1 19.3 - 21.3 41.3 - 45.6 99 - 870 2 19.1 - 21.8 38.9 - 52.1 85 - 340 3 23.6 - 24.2 38.3 - 50.3 265 - 447 4 25.8 - 28.2 48.0 - 53.9 493 - 1163 5 27.8 - 35.0 48.5 - 61.7 783 - 1076 RH* - Relative humidity LI** - Light intensity RESULTS and DISCUSSION Experimental results were confirmed the presence of formaldehyde in screen printing environment. The formaldehyde concentrations varied from 0.413 to 0.836 ppm (Table 2 and Fig. 1). Only facility 5 has the formaldehyde concentration above 0.75 ppm as the PEL (permissible exposure limit) value prescribed by OSHA (Occupational Safety and Health Administration) standard. The formaldehyde concentration levels were almost 1.11 to 1.82 times lower than PEL (facilities 1-4), whereas in facility 5 the formaldehyde concentration was 1.11 times higher than PEL value. According to the STEL (short-term exposure limit) value, the formaldehyde concentrations in all investigated facilities were below 2 ppm [7]. Based on the detected and quantified formaldehyde concentrations we confirm that printing raw materials (inks, cleaning solution, adhesive and paper) are the main emission sources of formaldehyde in screen printing indoor. Basically, formaldehyde and formaldehyde-releasing compounds are widely used as cross linking agents and binders in printing inks, biocides in water-based inks and fungicidal

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products. The concentrations of free formaldehyde in these products are generally less than 2%. During the printing these formaldehyde-based materials help bind dyes and pigments to fabrics, prevent colors from running, improve a fabric's resistance to wrinkles, ease clothing care and maintenance and prevent mildew. Additionally, unsaturated VOCs from conventional cleaning solutions in the reaction with ambient ozone contribute the releasing of formaldehyde in indoor environment. Table 2 Concentrations of formaldehyde in screen printing facilities Screen printing facility 1 2 3 4 5

Concentration (ppm) 0.413 0.678 0.564 0.451 0.836

MAC (ppm) PEL

STEL

0.75

2

Beside the chemical composition of raw materials the variations in the formaldehyde concentrations in screen printing facilities were related also to the ambient conditions, volume production, and distance from the printing desk, as well as the presence of ventilation installed in workplace. Numerous studies have reported that the indoor emission of formaldehyde increases with increasing of temperature and relative humidity [8]. In accordance with the literature it was confirmed the dependence of formaldehyde concentration on temperature and relative humidity. Therefore, increased concentration of formaldehyde in facility 5 was caused by a significant increasing of temperature and relative humidity (Table 1).

Fig. 1 Formaldehyde concentrations in screen printing facilities (1-5) Obtained results indicate that formaldehyde concentrations in press department of screen printing facility, especially in printing facility 5, have a potential risk factor to workers’ health. Many researches also confirm that formaldehyde can be toxic for human health and considered to be carcinogenic, mutagenic, or teratogenic [9, 10]. Thus, nowadays environmental regulations and EU Directives are increasingly pushing printing industry to reduce emission of formaldehyde, or find alternatives non-formaldehyde materials. The use of

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alternative materials is environmentally responsible choice that will reduce the generation of hazardous formaldehyde in screen printing environment. CONCLUSION This study provides experimental data concerning the indoor air pollution in screen printing facilities in Novi Sad for the first time. The main indoor sources of formaldehyde were conventional printing inks and cleaning solutions. The results pointed out that the manual screen printing processes generate formaldehyde in working environment due to the higher volume production (25-50 printed products during 1 hour) and application of conventional raw printing materials. During the production campaign, the formaldehyde concentration in screen printing facility 5 exceeds the PEL prescribed by the OSHA standard. Such high concentrations suggest that formaldehyde is the risk indoor air pollutant for workers. Thus, in order to better quantify the worker exposure level of hazardous formaldehyde it is recommended to carry out further investigation and long-term monitoring. ACKNOWLEDGMENT: The authors acknowledge the financial support of the Ministry of Science and Technological Development of the Republic of Serbia, within the Project No. 34014. LIST OF REFERENCES [1] World Health Organization, (2002). Concise International Chemical Assessment Document 40, Formaldehyde, Geneva, p. 1-81. [2] Printers’ National Environmental Assistance Center, Print process descriptions: Printing industry overview: Screen printing, http://www.pneac.org/printprocesses [3] Wen Z., Tianmo L., Zhongchang W., Susumu T., Mitsuhiro S., Yuichi I. (2009). Selective Detection of Formaldehyde Gas Using a Cd-Doped TiO2-SnO2 Sensor, Sensors 9, p. 90299038. [4] Kiurski J., Vojinovic Miloradov M., Krstic J., Radin Oros I., Adamovic D. (2009). Detection and influence of formaldehyde in the graphic environment, The 2nd Symposium of Chemistry and Environment, Book of Abstracts, Bar, Montenegro, pp. 124. [5] Kiurski J., Adamovic D., Krstic J., Oros I., Adamovic S., Mihailovic A., Grujic S. (2010). The influence of formaldehyde on printing indoor, The 12th DKMT Conference on Food, Environment and Health, Proceedings, Novi Sad, Serbia, pp.69. [6] Kats M. (1972). Methods of Air Sampling and Analysis, American Public Health Association, part 408: Tentative method of analysis for formaldehyde content of the atmosphere (colorimetric method), p.194. [7] Occupational Safety and Health Standards, Toxic and Hazardous Substances, Formaldehyde, Regulations (Standards - 29 CFR), Standard Number: 1910.1048, www.OSHA.gov. [8] Suh H. H., Bahadori T., Vallarino J., Spengler D. J., (2000) Criteria Air Pollutants and Toxic Air Pollutants, Environmental Health Perspectives 108(4), p. 625-633. [9] World Health Organization, International Agency for Research on Cancer, (2006). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 88, Formaldehyde, 2-Butoxyethanol and 1-tert-Butoxypropan-2-ol, Lyon, France. [10] Pinkerton L. E., Hein M. J., Stayner L. T. (2004). Mortality among a cohort of garment workers exposed to formaldehyde: An update, Occupational Environmental Medicine 61, p. 193-200.

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CADMIUM LEVEL IN SOME TISSUES AND ORGANS FROM WILD BOAR Măcinic Ioan, Trif Alexandra, Muselin Florin Department of Toxicology, Faculty of Veterinary Medicine Timisoara, Calea Aradului, 119, 300645, Romania. e-mail: ioan_macinic@yahoo.com

ABSTRACT The wild boar (Sus scrofa) is one of the most common species of Romanian wild game. It’s meat is found often on the market and in peoples menu list. One of the most dangerous heavy metals is cadmium. It has several toxic effects on: kidneys, liver, testes, bones [2, 5]. The study was carried out in three different areas regarding the contamination level with heavy metals: Forest District M., Forest District. C and Forest District S. Cadmium concentration was directly correlated with the pollution degree of the three different areas Forest District M. >Forest District C.> Forest District T. Cadmium concentration in wild boar tissues and organs was: in Forest District C. between 0.009 ppm and 0.341 ppm; in Forest District M. between 0.011 ppm and 5.346 ppm and in Forest District T. between 0.007 ppm and 0.123 ppm. INTRODUCTION In Romania the hunt is more and more popular and the wild game meat is more often found in peoples menu. One of the Romania’s wild game is the wild boar (Sus scrofa). It has a large spread on the country territory from Danube Delta till the Carpathians Mountains [1, 3]. Wild boars meat is often found on restaurants menu list and in supermarket. The industry development is higher and it is affecting the wild life through the pollutants that they release in the atmosphere. These pollutants are carried by wind drafts many kilometers away and so they have the possibility to come in direct contact with wildlife [6]. The areas were selected regarding the degree of risk pollution with heavy metals. MATERIALS and METHODS The study was carried out on 70 wild boars during four hunting seasons (2005-2009) in Forest District C. (county A.) and Forest District M. (county S.) and only two hunting seasons (2007-2009) in Forest District S. (county T.). The three Forest Districts had different level of heavy metals contamination.

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The aim of the study was to determine cadmium level in wild boar tissues (bones and muscles) and organs (heart, liver, kidneys, spleen, lungs and testes). Cadmium concentration was determined by atomic absorption spectroscopy (AAS AA-6650 Shimadzu) after microwave digestion by CHEM MARS X. The data were statistically performed by ANOVA method and Student test. RESULTS Cadmium level in wild boar tissues and organs was determined in samples collected during the legal hunting seasons. A summary of the results for cadmium concentration in wild boar tissues and organs from Forest District C. is given in table 1. Table 1. Cadmium concentration in wild boar tissues and organs from Forest District C. Hunting season Tissues and 2005-2006 2006-2007 2007-2008 2008-2009 organs Liver 0,081 0,097** 0,096ns 0,094ns – a /ns – b Kidneys 0,096 0,124** 0,341** 0,210** - a /** - b Lungs 0,064 0,064ns 0,082* 0,089* - a /* - b ns ns Heart 0,015 0,021 0,027 0,045ns – a /* - b Spleen 0,022 0,025ns 0,037ns 0,022** - a /ns - b ns Testicle 0,010 0,014 0,017* - a / Muscles 0,012 0,026** 0,031* 0,021** - a /** - b ns Bones 0,010 0,009 0,010ns – a / **: p<0,01; *: p<0,05; a / b: a / - 2008-2009 / 2007-2008; / b – 2008-2009 / 2005-2006

A summary of the results for cadmium concentration in wild boar tissues and organs from Forest District M. is given in table 2. Table 2. Cadmium concentration in wild boar tissues and organs from Forest District M. Hunting season Tissues And 2005-2006 2006-2007 2007-2008 2008-2009 organs Liver 0,256 0,364** 0,572** 0,561** - a /** - b Kidneys 2,340 3,541** 5,012** 5,346** - a /** - b Lungs 0,125 0,100** 0,091** 0,144** - a /** - b s ns Heart 0,096 0,134 0,135 0,125** - a /** - b Spleen 0,050 0,072** 0,110** 0,170** - a /** - b Testicle 0,045 0,030** 0,025**/ Muscles 0,065 0,072* 0,074** 0,146** - a /** - b Bones 0,011 0,011ns 0,012**/ **: p<0,01; *: p<0,05; a / b: a / - 2008-2009 / 2007-2008; / b – 2008-2009 / 2005-2006

A summary of the results for cadmium concentration in wild boar tissues and organs from Forest District T. is given in table 3.

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Table 3. Cadmium concentration in wild boar tissues and organs from Forest District T. Hunting season Tissues And 2007-2008 2008-2009 organs Liver 0,072 0,081ns Kidneys 0,123 0,105** Lungs 0,064 0,065** Heart 0,021 0,020ns Spleen 0,026 0,031ns Testicle 0,009 0,012ns Muscles 0,012 0,014** Bones 0,007 0,011ns

**: p<0,01 ; ns: nesemnificativ

Mean cadmium concentration dynamic in wild boar tissues and organs during the four hunting season in the three Forest Districts in summarized in figure 1. 4,5 4 3,5 3 2,5 2 1,5 1 0,5 0

2005-2006 2006-2007 2007-2008 2008-2009

Forest District C. Forest District S. Forest District T.

Fig. 1. Mean cadmium concentration in wild boar tissues and organs during 2005-2009 hunting seasons CONCLUSIONS ¾ cadmium concentration was directly correlated with the degree of pollution; ¾ tissues and organs hierarchy regarding cadmium concentration was: • in Forest District C.: kidneys, liver, lungs, heart, spleen, muscles, testicles, bones; • in Forest District M.: kidneys, livers, heart, lungs, spleen, muscles, testicles, bones; • in Forest District T.: kidneys, liver, lungs, spleen, heart, muscles, testicles, bones. ¾ cadmium concentration in tissues an organs for human consumption (muscles, liver, kidneys) overcome the maximum admitted limit (CE Directive 1881/2006) [7] for al

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samples and hunting season in Forest District M. and liver in Forest District T. (also both hunting seasons) and was under in Forest district C. and muscles and kidneys in Forest District T. LIST OF REFERENCES [1] Cotta, V., Bodea, M., Micu, I. (2001) – Vânatul şi vânătoarea în România, Ed., Ceres, Bucureşti; [2] Suteanu E., Danielescu N., Popescu O., Trif A.(1995) - Toxicologie si toxicoze, Editura Didactica si Pedagogica, R.A., Bucuresti, p. 138-140; [3] Şelaru, N. (1995) – Wild boar monogrphy, Ed., Salut-2000, Bucureşti [4] Walker, C. H., Hopkin, S.P., SIBLY, R. M., PEAKALL, D.B., (2006) - Principles of ecotoxicology, Third Edit., Taylor FRANCIS; [5] Wolkers, H., Wensing, T., Groot-Bruinderink, G. W., (1994), Heavy metal contamination in organs of red deer (Cervus elaphus) and wild boar (Sus scofra) and the effect on some trace elements, Sci Total Environ 144 p. 191–199; [6] Young, R. A., (2002) – Toxicity Summary for Cadmium, Chemical Hazard Evaluation and Comunication Group, Biomedical and Environmental. Information Analysis section, Health and Safety Research Division, http://www.risk.lsd.ornl.gov/tox/profiles/cadmium.shtml; [7]*** CE Directive nr. 1881/2006, http://www.legis.ro;

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LEAD LEVELS IN SOIL-WATER-PLANT CHAIN FROM A FORESTY ECOSYSTEM Trif Alexandra, Măcinic Ioan, Muselin Florin Department of Toxicology, Faculty of Veterinary Medicine Timisoara, Calea Aradului, 119, 300645, Romania e-mail: al_trif@yahoo.com ABSTRACT Lead level was determined in soil (20 cm and 40 cm deep), water (water sources for wild game) and plants from three Forest Districts placed in areas with different degree of pollution. Determination of lead concentration was made in forestry ecosystem to see the impact of heavy metals (lead) on wildlife. In soil lead concentration was in limits at both depths (20cm and 40 cm) for all three Forest Districts, in water samples lead level exceeded the maximum admitted limit for drinking water (0.01 ppm) and for surface water (0.01 ppm) and from ecological point of view were in the Vth quality class. Lead concentration was under the maximum admitted limits for plants in all three Forest Districts. INTRODUCTION Lead is known as a heavy metal with high risk of pollution [2, 3]. It has several impacts on digestive tract, kidneys, bones, nervous system [1]. Lead concentration was determined to see lead impact on forestry ecosystem and the risk level for heavy metals pollution. The industry was place within 10-40 km from the research areas. One area was placed near a heavy polluting industry and the other two were placed in areas known as areas with low risk of pollution or unpolluted. MATERIALS and METHODS The study was carried on soil, water and plants samples during two hunting seasons (2007-2009) in three different area regarding the level of pollution: Forest District C. (county A.), Forest District M. (county S.) and Forest District T (county T.). The aim of the study was to determine lead level in the food chain from a forestry ecosystem. Lead concentration was determined by atomic absorption spectroscopy (AAS AA6650 Shimadzu) after microwave digestion by CHEM MARS X. The data were statistically performed by ANOVA method and Student test.

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RESULTS Lead concentration was significantly higher (p<0.01) at 20 cm than at 40 cm depth. At 20 cm depth lead concentration was lower than maximum admitted limit in all three Forest Districts (figure 1). 20 15 10 5 0 . e T. C. tM alu ct ct c i i v i r r r al ist ist ist rm tD tD tD o s s s N re re re Fo Fo Fo

Fig. 1 . Lead concentration in soil during 2005-2009 period at 20 cm depth (mean values) Lead concentration in water exceeded maximum admitted limits for drinking water (0.01 ppm according Law 458/2002) [5] and surface water (0.01 ppm according HG 100/febr. 2002) [4] and according to MMGA nr.161/2006 the quality class was V [6]. Lead concentration in water from forestry ecosystem is summarized in figure 2.

Ocolul Silvic Timişoara Ocolul Silvic Mediaş Ocolul Silvic Criş 0

5

10

15

20

25

30

35

40

Fig. 2. Lead concentration in water samples during 2005-2009 period In plants lead concentration was between 2.0 ppm and 2.2 ppm in Forest District C.; between 5.5 ppm and 5.6 ppm in Forest District M. and between 1.8 ppm and 1.9 ppm in Forest District T.

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CONCLUSIONS 9 lead concentrations in soil were in limits for all three Forest District at both depths (20cm and 40 cm); 9 lead concentrations in water were higher than maximum admitted limit not only for drinking water, but also for surface water (0.01 ppm). From ecological point of view all three Forest District were in the Vth class; 9 lead levels were in limits for plants in all three Fosrest Districts; 9 regarding lead level in soil, water, plants the hierarchy was: Forest District M.>Forest District C.>Forest District T.

REFERENCES [1] Crivineanu V., Rapeanu D.M., Crivineanu M.(1996) - Toxicologie sanitara veterinara, Editura Coral Sanivet, Bucuresti, p. 188-192; [2] Rahde, F. A., (1994) – Lead, innorganic http://www.inchem.org/documents/pims /chemical/inorglea.htm; [3] Thompson, P., Monroe, M., (1999) – Lead and its inorganic compounds – Safe Sci Newslett, http://www.orcbs.msu.edu ; [4] ***Hotărârea nr. 100/7.02.2002, http://www.legis.ro; [5] ***Legea nr. 458/2002, http://www.legis.ro; [6] *** Ordinul MMGA nr. 161/2006, http://www.legis.ro;

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SAWDUST AS LOW-COST NATURAL ADSORBENT FOR REMOVAL OF Cu(II) IONS FROM AQUEOUS SOLUTIONS Mariana Albulescu1, Popovici Horia1, Popa Maria2, Ljubiša Obradovič3 1

West University of Timisoara, Faculty of Chemistry, Biology, Geography, Pestalozzi Street no. 16, 300115, Timisoara, Romania, Malbulescu@yahoo.com 2 University "1 Decembrie 1918", N. Iorga street, no. 11-13, Alba Iulia, Romania 3 Mining and Metallurgy Institute Bor, Zeleni bulevar 35, Bor, Serbia

ABSTRACT Nowadays heavy metals are reported as priority pollutants, due to their mobility in natural water ecosystems and their toxicity; they are among the most important pollutants in source and treated water, and are becoming a severe public health problem. Cellulose can adsorb heavy metals from solution. In this paper, the inexpensive and effective metal ion (Cu2+) adsorbent from wood-waste materials (sawdust) was investigated using the biosorption process, which is a relatively new process that has proven very promising in the removal of metals ions from aqueous effluents. The results show that the biosorbtion of copper ion occurs with higher yields in alkaline solution (pH= 8.5), the adsorption equilibrium is quickly reached (after 15-30 minutes) and copper ions can be removed extensively from aqueous solution after successive adsorption stages. INTRODUCTION Since the industrial revolution, anthropogenic impacts have caused many hazardous substances releasing to environment. Heavy metal pollution is today one of the most important environmental and public health problem caused by heavy metals toxicity and other adverse effects on water bodies. Various industries produce and discharge wastes containing different heavy metals into the aquatic environment such as mining and smelting of metalliferous, surface finishing industry, energy and fuel production, fertilizer and pesticide industry and application, metallurgy, iron and steel, etc. [1÷3]. Conventional methods for removal of metal ions from aqueous solutions include chemical precipitation, electrochemical treatment, ion exchangers, reverse osmosis, electrodialysis, membrane technologies, etc. Since 1990’s the adsorption of heavy metal ions by low cost renewable organic materials has gained momentum [4]. The process of adsorption implies the presence of an “adsorbent” solid that binds molecules by physical attractive forces, ion exchange, and chemical binding. It is advisable that the adsorbent is available in large quantities, easily regenerable, and cheap [5]. Biosorption can be defined as the removal of metal or metalloid species, compounds and particulates from solution by biological material [6]. The major advantages of biosorption over conventional treatment methods include: low cost, high efficiency, minimization of chemical or biological sludge, no additional nutrient requirement, and regeneration of biosorbents and possibility of metal recovery. The sorption capacity of lignocellulosics for metal ions is generally described as adsorption and this is the most attractive method due to its simplicity, convenience and high removal efficiency [7÷9]. One metal that is targeted for the development of new removal techniques is copper. Copper is a bio-essential element, e.g. the adult daily requirement for human beings estimated to be 2 mg; however, ecological impacts may be observed when copper concentrations exceed 0.2 mg/ L [5]. Utilization of sawdust also played significant role in removal of copper and

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other metal ions [10-13]. The main component of sawdust is cellulose (Fig 1) with proven adsorbtion properties. Figure 1. Structure of cellulose, an organic compound with the formula (C6H10O5)n, a polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4) linked Dglucose units Sawdust is a forestry by-product, composed of fine particles of wood. In countries with strong forestry industry such as Romania, sawdust is produced in large quantities but at this moment, less valorized. For this reason we have proposed to study the adsorption capacity of sawdust for copper ions, first in synthetic aqueous solutions. MATERIALS and METHODS •

• •

Batch studies were conducted using synthetic Cu2+ solution to assess adsorption studies. Working solution was prepared by successive dilutions from stock solution (solution I) of Cu2+ with concentration 0.4 moles Cu2+ /L (0.4 M respectively 25.400 ppm) obtained by dissolving in a volumetric flask of 1000 mL a 100 g CuSO4*5H2O in distilled water; 1 mL of this solution was diluted to100 mL obtaining the solution II (254 ppm). 10 mL of solution II was diluted with water in a volumetric flask to 250 mL and the final solution (III) containing 10.16 ppm Cu2+ (1.6*10-4M) was prepared. Sawdust samples were obtained from some wood factories located in Faget area, Timis County. It has been used without being crushed before. Determination of Cu2+: a volumetric method was used, respectively: over 0.1 ml of sample 50 ml distilled water was added 3 ml acetic acid (1M) and 0.1 ml of indicator solution alcohol (PAN). Titration was done with complexone solution III EDTA (0.01 M), turn indicator is red-orange to greenish yellow. Factor solution is verified daily. [14].

RESULTS In laboratory experiments we have used two types of oak sawdust samples from different source. Their adsorption capacity was evaluated comparatively in two ways: without preliminary draying (series A) and after drying at 105 0 C, to constant weight (series B; humidity of sawdust samples was between 9.5 and 10%). The results are presented in Table 1. It can be seen that: • sawdust adsorb quickly copper ions; 15 minutes are sufficient; after 45 minute (sample 1) and about 30 minute (sample 2) , sawdust efficiency decreases slightly; • there are differences between the two samples of oak sawdust on adsorption capacity of Cu2+ ions, probably because of different degree of crushing, age of the trees, chemical composition; • the drying process of sawdust is not advantageous because the adsorption capacity of copper ion decreases by 8.7-16.7% for sample 1 and by 30-50% for oak sawdust, sample 2; 2+ • 1 g of undried sawdust can retain 10.16÷11.10 mg/L Cu (sample 1) or 12.10-12.74 2+ mg/L Cu (sample 2). The pH effect was investigated as well. Determinations of adsorbtion capacity were made after 15 and 30 minutes and could be observed differences depending on the pH of

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aqueous solution. The most favorable pH is the alkaline one (pH 8.5) when the results increased by 30-40%. At a higher pH copper ions precipitate. A Cu2+ solution with pH 5 lead to slightly better results than those obtained at pH 6.4; at lower pH, percentage of retention of copper ions significantly decreases probably due to sorbent protonation effect. Table 1. Effect of adsorption time and sawdust drying on cupper adsorption capacity (synthetic solution Cu2+ 1.6*10-4M) Sawdust Experimental Adsorption ratio Adsorption % removal, Cu2+ (mg/L) sample conditions time, 100 (Ci-Cf)/ /Ci, adsorbed by mL aq. Cu2+/ minute 1 g sawdust weight of sawdust (g) A1.

Undried oak chips, sample 1, 250C, magnetic stirring (500rpm), pH = 6.4

500:1

A2

Undried oak chips, sample 2, 250C, magnetic stirring (500rpm), pH = 6.4

500:1

B1

Dried oak chips, sample 1, 250C, magnetic stirring (500rpm), pH = 6.4

500:1

B2

Dried oak chips, sample 2, 250C, magnetic stirring (500rpm), pH = 6.4

500:1

15 30 45 60 75 90 15 30 45 60 75 90 15 30 45 60 75 90 15 30 45 60 75 90

50.03 51.87 54.62 53.89 53.12 52.65 58.25 60.60 63.10 62.15 61.75 61.50 49.35 47.32 44.38 45.63 44.38 43.78 32.08 32.13 30.20 30.62 30.97 28.72

10.16 10.54 11.10 10.84 10.74 10.62 11.84 12.32 12.82 12.74 12.18 12.10 10.06 9.50 8.94 9.20 8.94 8.82 6.58 6.68 6.12 6.14 6.26 5.86

Taking into consideration the findings so far we have tried to retain the Cu2+ ions in three successive adsorption stages. The results are shown in Figure 2. Retention percentage after the first cycle of adsorption of ions is 52% and in the following two cycles 67.68 % and 73% respectively, which would allow the removal of heavy metal ions by using batteries of adsorption. I II III 2+ Cu , 10.12 mg/L 4.85 mg/L 3.27 mg/L 2.73 m/L Figure 2. Concentration of Cu2+ solution after successive adsorption stages on cellulosic material (oak sawdust)

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CONCLUSIONS Cellulose can adsorb heavy metals from solution. The polar solvent molecules are attracted to the dry solid matrix and held by hydrogen bonding forces between the –OH or – COOH groups in the wood structure. Sorption potential of untreated sawdust copper from aqueous media was explored. The effects of pH, initial concentration, biosorbent dosage and contact time were studied in batch experiments. The results show that: • the adsorbtion of copper ion occurs with higher yields in alkaline solution (pH 8.5); • the adsorption equilibrium is quickly reached, after 15-30 minutes working at room temperature (250C); • 73% of copper ions can be removed from the solution after three adsorption stages. ACKNOWLEDGEMENTS: This paper was partially supported by Romania-Republic of Serbia IPA Cross-border Cooperation Programme, within project MIS-ETC Code 464, subsidy contract from IPA No 8518. LIST OF REFERENCES [1] Fenglian Fu, Qi Wang (2011). Removal of heavy metal ions from wastewaters: A review, Journal of Environmental Management. 92, p. 407-418. [2] Jianlong Wang, Can Chen. (2009). Biosorbents for heavy metals removal and their future. Biotechnology Advances. 27, p.195–226. [3] Shuguang Lu, Stuart W. Gibb. (2008). Copper removal from wastewater using spent-grain as biosorbent, Bioresource Technology, 99(6), p. 1509-1517. [4] Umar Farooq, Janusz A. Kozinski Misbahul Ain Khan, Makshoof Athar. (2010) Biosorption of heavy metal ions using wheat based biosorbents – A review, of the recent literature, Bioresource Technology, 101, p. 5043–5053. [5] Ayhan Demirbas (2008). Heavy metal adsorption onto agro-based waste materials: A review, Journal of Hazardous Materials 157, p. 220–229. [6] Gadd, G. M. White, C. (1993). Microbial treatment of metal pollution –a working biotechnology ?. Trends Biotechnol., 11, p. 353-359. [7] Dhiraj Sud, Garima Mahajan, M.P. Kaur (2008). Agricultural waste material as potential adsorbent for sequestering heavy metal ions from aqueous solutions – A review. Bioresource Technology 99, p. 6017–6027. [8] Jianlong Wang, Can Chen. (2009). Biosorbents for heavy metals removal and their future. Biotechnology Advances. 27, p. 195–226. [9] Upendra Kumar (2006). Agricultural products and by-products as a low cost adsorbent for heavy metal removal from water and wastewater: A review, Scientific Research and Essay. 1 (2), p. 033-037. [10] Nag, A., Gupta, N., Biswas, M.N. (1998). Removal of chromium (VI) and arsenic (III) by chemically treated saw dust. Ind. J. Environ. Protect.19, p. 25–29. [11] Raji, A.K., Anirudhan, T.S., (1998). Sorptive behaviour of chromium (VI) on sawdust carbon in aqueous media. Ecol. Environ. Conserv. 4, p. 33–37. [12] Raji, C., Shubha, K.P., Anirudhan, T.S. (1997). Use of chemically modified sawdust in the removal of Pb (II) ions from aqueous media. Ind. J.Environ. Health 39, p. 230–238. [13] Larous, S., Meniai, A.H., Lehocine, M.B. (2005). Experimental study of the removal of Cu from the aqueous solutions by adsorption using saw dust. Desalination 185, p. 483–490. [14] Liteanu C. “Chimie analitică si didactică. Volumetria”, Ed. 5, Editura Didactică si Pedagogică, Bucuresti, 1969, p. 605.

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In memoriam Gaál Ferenc

Gaál Ferenc 1941-2011

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Prof. Dr. Gaál Ferenc akadémikus, nyugalmazott egyetemi tanár 2011. szeptember 6-án 70 éves korában váratlanul elhunyt. 1941-ben, Adán született. Az általános iskolát szülővárosában (1948–1956), a vegyészeti technikumot Szabadkán (1956– 1960) végezte. Mérnöki diplomáját a Belgrádi Egyetem Vegyészmérnöki Karán 1964-ben szerezte. Magiszteri fokozatát 1968-ban és a kémiai tudományok doktora cimét 1977-ban a Belgrádi egyetem Természettudományi Karán szerezte meg. Oktatói pályáját az Újvidéki Egyetem Bölcsészettudományi/Természettudományi Karának Kémia Tanszékén tanársegédként kezdte 1965-ben. Docenssé 1978-ban, rendkívüli egyetemi tanárrá 1983-ban, rendes egyetemi tanárrá

pedig 1990-ben

választották. Alapító tagja és sok éven át vezetője volt a Természettudományi Kar Kémiai Intézete Analitikai Kémiai Tanszékének. Több mint 40 éven át oktatott és kutatott az analitikai kémia területén. Tudományos téren elsősorban műszeres analízissel, és környezetvédelemmel foglalkozott. Több mint 180 tudományos publikáció és szakdolgozat szerzője vagy társszerzője, független idézeteinek száma meghaladja az 500-at. Több neves folyóirat felkért szakmai birálója volt. Számos hazai és nemzetközi tudományos projekt részvevője, illetve vezetője volt. Több tudományos, műszaki és civil szervezetnek volt aktiv tagja. Tudományos és Művészeti Akadémia levelező

(2004-2010),

A Vajdasági

majd rendes tagja

(2010-), a Vajdasági Magyar Tudományos Társaság elnökségi tagja (2002–), a Szerb Kémikusok Egyesülete többszöri elnökségi tagja, 2001-től tiszteletbeli tagja volt. Alapitó tagja és elnöke (1980–1982) volt

a Vajdasági Kémikusok Egyesü-

letének, tiszteletbeli taggá 2001-ben választották. A Jugoszláv Kémikusok Szövetségének főtitkári tisztét 1982–1984 töltötte be. Az Európai Kémikus Egyesületek Szövetsége Analitikai Kémiai Munkabizottságának tagja (1980–2002) volt. A Magyar Tudományos Akadémia köztestületének tagja 2001-ben lett. A Vajdasági Magyar Felsőoktatási Kollégium, alapitó tag és tagja volt a Vajdasági Magyar Akadémiai Tanácsnak (2008-) is. Tudományos munkásságáért a Vajdasági Autonóm Tartomány tudományos plakettel tüntette ki (1990). Tevékenyen segítette a Szegedi Akadémiai Bizottság Kémiai Szakbizottságának, különösen az Analitikai és Környezetvédelmi Munkabizottságának munkáját. Rendszeres résztvevője, szervezője volt az „International Symposium on Analitikai

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and Environmental Problems“ , immáron 2011-ben 17. alkalommal megrendezett Szimpóziumnak. Ezen a helyen Gaál Ferenc több évtizedes fáradhatatlan és odaadó munkájára emlékezünk.

Galbács Zoltán A SZAB Analitikai és Környezetvédelmi Munkabizottság elnöke

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SOME CONSIDERATIONS CONCERNING THE MS ANALYSIS OF COMPLETELY PROTECTED THIOGLYCOSIDES WITH HETEROCYCLIC AGLICONE A. Lascu1, V. Bercean2, E. Şişu3 1 Institute of Chemistry Timisoara of Romanian Academy, No.24 Mihai Viteazul Bd., RO300223, Timişoara 2 “Politehnica” University, Faculty of Industrial Chemistry and Environment Engineering, No. 2 Victoriei Sq., RO-300006, Timişoara 3 ”Victor Babeş” University of Medicine and Pharmacy, No.2 Eftimie Murgu Sq., RO-300041, Timişoara Introduction The synthesis and investigation of the biological activity of 1,2,4-triazole glycosides [1] have been stimulated by the finding that Ribavirin (b-D-ribofuranosyl-1,2,4-triazole-3carboxamide) is remarkable in its broad spectral activity against DNA and RNA viruses. Encouraged by these interesting structures and biological activities, we found that it would be of great interest to synthesize some novel 1,2,4-triazole glucosides to investigate their antibacterial and antifungal activities. Along with the most commonly used magnetic resonance spectroscopy, modern mass spectrometers allow molecular mass determination, and the generation of fragmentation data that leads to structure elucidation, generally in tandem mass-spectrometric experiments [2]. Methods The proton spectra were recorded on a Varian 300 MHz spectrometer. Mass spectrometry was performed on a High Capacity Ion Trap (HCIT) Ultra PTM mass spectrometer (Bruker Daltonik, Bremen, Germany). The HCT mass spectrometer is interfaced to a PC running the Compass integrated software package under WindowsXP, which includes EsquireControl and Hystar modules for instrument tuning, control and spectrum acquisition, and DataAnalysis software for storing the ion chromatograms and processing the MS data. The samples were infused into MS by online syringe pump electrospray at a constant flow rate of 250 μl/h. Nitrogen at a flow rate of 10 l/min was employed at 300 °C for desolvation and as a nebulizer gas at 15 p.s.i. The instrument was set to operate in the positive ion mode under 3.0 kV ESI potential. For MS analysis the sample was dissolved to a concentration of about 5 pmol/µL, in MeOH/H2O/HCOOH (1:1:0.001 v/v). Discussion The S-glycosides under investigation were synthesized by our group for the first time, as previously described [3,4] and were characterized by melting point, 1H-NMR, 13C-NMR and (+)ESI-IT-MS. The MS spectra of the above mentioned compounds were registered in positive ion mode and reasoned through pseudomolecular ions [M+H]+ and [M+Na]+ the presence of thioglycoside. MS2 spectra of the isolated pseudomolecular ions are presented in Figures 1-3. The compounds under investigation were of the general formula:

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OAc O OAc S AcO OAc

N N R

N H

R = H, CH3, OCH 3

The literature concerning the MS analysis of such compounds is scarce, most being performed with GC-MS methods, whereas the more sensitive ESI-IT-MS methods are mentioned by our group [5,6,7]. The fragmentations corresponding to the loss of ketene, acetyl and acetic acid, specific for peracetylated derivatives [8], were also identified. In our study, we optimized our ESI-IT-MS and CID MS2 methodology for the first mass spectrometric investigation of thioglycosides derived from 3-mercapto-5 substituted 1,2,4 – triazole. The soft ionization techniques generate predominantly even-electron ions (whether [M+H]+, [M+Na]+, [M-H]-, etc.) which fragment to generate even-electron fragments [9]. Most of the positive-ion fragments can be reasoned as having similar structures, whether the charge-bearing species is a proton or an alkali metal cation, most commonly a sodium ion. The weakest bond in a glycoconjugate and thus generally the easiest to fragment mass-spectrometrically is the glycosidic bond. Peracetylated glycosides are fragmented somewhat more complex than the deprotected thioglycosides, due to the fact that an acetoxyl group can be eliminated as four different radicals: CH3COOH, CH3COO.,CH3CO. and CH2=C=O [10]. M+Na Intens .

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Figure 3: (+)MS2 spectrum for compound where R = OCH3 Conclusions Both (+)MS2 spectra of the sodiated species present the characteristic ions for the elimination of the acetate protecting groups. The MS2 spectra in both cases reinforce and confirm without doubt the proposed structure, that was also reasoned by 1H-NMR and 13C-NMR analysis. The (+)MS2 spectrum of the compound where R = CH3 presents the characteristic fragment resulting from the breaking of the glycosidic bond, which represents the weakest bond in the molecule. References 1. The Pharmacology of Ribavirin; Smith, R. A., Kirkpatrick, W., Eds.; Academic Press: London, 1980; pp 133–156. 2. Penescu M., Şişu I., Purcărea V.L., Şişu E.- Farmacia, 2009, 57(6), 667-680 3. E. Şişu, A. Lascu, V.Bercean, M. Căproiu, A. Zamfir, I. Şişu, C. Neanu, C. Csunderlik, V. Rusu and J. P. Katalinic -Rev. Chim. (Bucharest), 2003 54(2), pg.181-1845. 4. Lascu A., Şişu I., Bercean V., Lupea A.X., Căproiu M.T., Şişu E.- Rev. Roum. Chim. 2010, 55(3), p. 205-210 5. A. Lascu, I. Şişu, V. N. Bercean, A. X. Lupea, N. Dincă, A. D. Zamfir, E. Şişu - 2nd International Conference of the Romanian Society for Mass Spectrometry (RSMS), 1-5 May 2011 - Book of Abstracts p.44 6. A. Lascu, I. Şişu, V. N. Bercean, A. D. Zamfir and E. Şişu - 2nd International Conference of the Romanian Society for Mass Spectrometry (RSMS), 1-5 May 2011 - Book of Abstracts p.45 7. E. Şişu, I. Şişu, A. Lascu, M. Căproiu, C. Neanu, V. N. Bercean - Annals of West University of Timisoara, Series of Chemistry 19 (4) (2010) p.75-82 8. N. K. Kochetkov, O.S. Chizhov, Adv. in Carbohydr. Chem., Eds. M.L. Wolfrom, Academic Press New York, vol 21, 1966, p. 61 9. Penescu M., Purcărea V.L., Şişu I., Şişu E.- J. Med. Life, 2010, 3(2), p. 128-136 10. Zaia J.- Mass Spectrom. Rev., 2004, 23, p. 161-227

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NEUROTOXICITY OF MANGANESE ANALYSED BY A NOVEL COMBINED ELECTROPHYSIOLOGICAL-BEHAVIORAL RECORDING SYSTEM Takács Szabolcs, Papp András Department of Public Health, University of Szeged Faculty of Medicine Email: takszabi@gmail.com ABSTRACT A novel electrophysiological-behavioral recording system, developed by Experimetria Ltd., Hungary in cooperation with our Department, was used to study the effects of manganese, a neurotoxicant frequently causing human nervous system disease in occupational exposure. Male Wistar rats were equipped with a “crown” enabling the recording of electrocorticogram (ECoG) in awake, freely moving state. One 60-min recording session per week was held for 10 weeks, in which the rats’ movements in an open field (OF) box and their ECoG were simultaneously recorded. After the 2nd week, treated rats had 7.5 mg/l MnCl2 in the drinking water (control: normal tapwater) and further 8 recordings were made. From the OF records, ambulation distance and the time spent with ambulation, local activity and immobility was obtained. From the ECoG, power spectrum and total power was calculated. In the first weeks of Mn exposure, the rats’ motility substantially decreased, and these changes showed little further progression. The decay of motility during one 60-min session was also stronger in exposed rats. The total power of ECoG increased in the first 4 weeks but the spectrum was hardly changed. The total power and spectrum of ECoG and the level of motility were apparently correlated, and the functional alterations showed some dependence on treatment time and/or summed dose. Combined, repeated ECoG and motility recording is suitable to follow-up the development of neurotoxicity induced by Mn, and possibly other environmental neurotoxicants. INTRODUCTION The increasing number of xenobiotics with potential risk to human heath urges a need for more sensitive methods in the diagnosis of the alterations caused. To preserve health these effects must be detected as early as possible, because long-term exposure can lead to severe symptoms even in absence of obvious signs. This is especially true to the nervous system where any substance, able to cross the blood-brain barrier, can have a major effect on humans. Various biomarkers are used to detect alterations induced by xenobiotics; these are measurements that indicate the exposure to a chemical, the effect of such exposure, or susceptibility to a (usually toxic) effect of such exposure (Hayes, 2001). For neuro-functional alterations, the generally used chemical biomarkers are not ideal, so the development of markers based on electrophysiological recording may be a promising field of investigation. In the present work, Wistar rats were implanted chronically with epidural electrodes to record spontaneous cortical electrical activity (electrocorticogram, ECoG) in awake animals, simultaneously with the recording of motor behaviour in an open field box. It was tested how the measured data and their correlations could be used as an indicator of toxic damage and its progression.

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The test substance chosen was manganese. Numerous data testify its effect at the molecular and neuronal level, and the late consequences on human exposure, but less is known about the development of the functional alterations. Mn itself is a trace element essential in a number of biological functions e.g. as cofactor of enzymes (ATSDR, 2008). Excess Mn alters the activity of the mitochondrial superoxide dismutase and can inhibit the removal of glutamate by glia-specific glutamine synthetase (Normandin and Hazell, 2002), which leads to excitotoxicity and oxidative stress in the brain. This, together with mitochondrial dysfunction (Zhang et al., 2003) affects first of all dopaminergic structures. In the long run this results in manganism, an occupational disease resembling Parkinson’s disease. In the present work, Mn was applied via the rats’ drinking water, modelling cases of human nervous system damage due to high-Mn drinking water (e.g. in Greece: Kondakis et al., 1989). In the affected Greek population, motor symptoms and hair Mn levels were strongly correlated in persons over 50 years of age. Electrophysiological (spontaneous and evoked cortical activity) and behavioural (open field, acoustic startle response etc.) effects of subacute oral Mn exposure have already been investigated at our Department on rats, e.g. by Vezér et al. (2005) – with the shortcoming, however, that cortical electrical activity was recorded in anaesthesia and hence could not be directly put in parallel with the behavioural effects. With the method described here, the two can be recorded simultaneously in wake state. METHODS Male Wistar rats of ca. 350 g body weight were prepared for repeated ECoG recording by means of chronically implanted electrodes: Four small holes were drilled in the skull in isoflurane anaesthesia (2-3vol% in O2, open system) down to the epidural space over the right and left frontal and parietal lobe. Two holes received fine steel screws which served as electrodes and fixed the “crown” used for electrical connection, while in the other two holes, silver wire electrodes were placed. The screws and the silver wires were electrically connected to the crown base and the base was secured to the skull with dental acrylic. The skin was sutured and the rats were allowed to recover for 11-14 days before the first recording. Before and after surgery, sufficient analgesic and antibiotic treatment was given. Altogether 5 such animals were prepared and used (see Takács and Papp, 2010 for more details). Weekly one recording session of 60 min duration was held with each animal. After the first two weeks as control period, four of the five rats had 7.5 mg/ml manganese chloride (MnCl2⋅4H2O analytical grade, Reanal, Hungary) in their drinking water while the fifth had normal tap water and served as parallel control (the natural Mn level of the local tap water was 0.03 μg/ml). The intended length of the Mn exposure period was eight weeks. The procedures applied were approved by the Ethical Committee for the Protection of Animals in Research of the University. A combined system (provided by Experimetria Ltd, Hungary) was used for parallel recording of motility and cortical activity. The rat was in an open field (OF) box, detecting and analysing its movements by means of a grid of infrared light gates. From the light beam interruptions, counts, time and run length of the basic activity forms (ambulation, local activity, immobility) were computed by the software of the OF box (Conducta 1.3, Experimetria, Hungary). Cortical electrical activity was recorded via a cable connected to the crown. The two electrodes above the left and right hemisphere gave one bipolar lead-off each. Signals from the left hemisphere (channel 1) were always used for analysis unless they were strongly distorted for technical reasons. The pre-amplified signals were fed via swivel contact in the

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main amplifier. Overall amplification was 104x with low- and high-pass filters set to 1.6 and 75 Hz. The ECoG signals were visualized on the PC monitor in real time and stored on the HDD. Off-line analysis (using a purpose-developed software by Experimetria) provided the power spectrum between adjustable limits with 0.5 Hz resolution. The complete spectrum between 5.5 and 49 Hz was generated, and the total power (the sum of the power in the 0.5 Hz wide bins) was calculated. Mn level in the blood and brain of the treated rats was determined by inductively coupled plasma mass spectrometry after acidic digestion. Due to the small data pool, no statistical evaluation was done, and it is planned to repeat the experiment with more animals. Linear regression between different data was calculated, and its significance tested, by the “linear fit” function of MS Excel. RESULTS Oral Mn exposure resulted in substantial accumulation of Mn in the brain, but not blood, of the treated rats (brain: 5113±1025 vs. 1931±476 ppm; blood: 502±115 vs. 514±217 ppm; untreated controls from another experiment). The effect on the ECoG appeared in two distinct phases. The total power (Fig. 1A) was massively increased in ca. the first 4 weeks of exposure, compared to the control animal, but later this change turned to the opposite. The changes in the spectrum curve were small (first increase in most part of the range, then decrease above 30 Hz) and were in concordance with the data of total power. Rel. Change

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Figure 1 A: Total ECoG power (between 5.5 and 49 Hz) in the control and Mn-treated period (n= 4 treated and 1 control); relative data on the basis of the two control weeks. The dark line below the graph signalizes treatment period. B: ECoG power spectrum of the treated rats, averaged from data of the 4 treated animals.

In the OF activity, oral exposure by Mn caused decreased motility in the treated vs. control rats (Fig. 2A). This effect was also more pronounced in the first 4 weeks of exposure. The best indicator was the time spent in immobility, the course of which in the pre-treatment and treatment period is shown in Fig. 2B. Comparison of the graphs in Fig. 1A and 2B suggested that ECoG activity and motility change in parallel and are possibly in causal relationship. To test that in more detail, the 60min records were analyzed in 10-min sections and the outcome was separately averaged for the 2 pre-treatment weeks and the 4+4 treatment weeks.

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Local activity Ambulation

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This kind of analysis also showed that increasing ECoG power was concomittant with decreased motility (Fig. 3). The best correlation existed (also suggested by the lines in the graphs) between the ECoG power and the time spent in immobility. For the first 4 treatment weeks, R2=0.386 for the treated and R2<<0.1 for the control; for all 8 treatment weeks the relationship was less clear, in accordance with the time course of the electrical and motor activity shown in Fig. 1 and 2. CONCLUSION The treated rats’ decreased motility can be likened to adult human manganism, and most probably results from the effects of Mn on the metabolism of transmitters in the CNS, such as glutamate, dopamine or GABA. Locomotor activity in rats depends on mesolimbic and mesocortical dopaminergic neuronal transmission (Fink and Smith, 1980). It is generally assumed that Mn in the brain diminishes the activity of dopaminergic regulation and, hence, motor activity. High cortical electrical activity together with total or subtotal immobility is typical for some forms of epilepsy (petit mal). Mn intoxication is known to induce epileptic activity mainly in children (Hernandez et al. 2003) but also in young adults (Ono et al., 2002). The method described is apparently suitable for modelling and following-up neuro-functional alterations of environmental origin, but could be used in any case of purposeful or accidental external chemical influence on the central nervous system.

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Rel. ECoG power Mn-treated

2

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Next 4 weeks Mn

0 1 2 3 4 5 6

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Figure 3 Changes of the ECoG power and the three forms of OF activity within the 60-min recording sessions before and during Mn exposure. The values were normalized to the first 10-min period of the pre-treatment weeks. REFERENCES ATSDR (2008). Draft toxicological profile for manganese. Agency for Toxic Substances and Disease Registry, U.S. Department of Health and Human Services. Atlanta, USA Fink JS, Smith GP (1980) Relationships between selective denervation of dopamine terminal fields in the anterior forebrain and behavioral responses to amphetamine and apomorphine. Brain Res. 20, 107-127. Hayes AW (2001) Principles and Methods of Toxicology. Taylor and Francis, Boston, pp. 432-434. Hernandez EH, Discalzi G, Dassi P, Jarre L, Pira E (2003) Manganese intoxication: The cause of an inexplicable epileptic syndrome in a 3 year old child. NeuroToxicol. 24, 633–639. Kondakis XG, Makris N, Leotsinidis M, Prinou M, Papapetropoulos T (1989) Possible health effects of high manganese concentrations in drinking water. Arch. Environ. Health 44, 175-178. Normandin L, Hazell AS (2001) Manganese neurotoxicity: an update of pathophysiologic mechanisms. Metab. Brain Dis. 17, 375-387. Ono K, Komai K, Yamada M (2002) Myoclonic involuntary movement associated with chronic manganese poisoning. J. Neurol. Sci. 199, 93–96. Takács Sz, Papp A (2010) Effects of antiepileptics and an anesthetic on basal cortical activity and spontaneous motility in an epilepsy-prone rat strain. Acta Physiol. Hung. 97, 480-481. Vezér T, Papp A, Hoyk Z, Varga C, Náray M, Nagymajtényi L (2005) Behavioral and neurotoxicological effects of subchronic manganese exposure in rats. Env. Toxicol. Pharmacol. 19, 797-810.

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THE APPLICATION OF ZVI BASED IRON-GELS IN REMEDIATION TECHNIQUES Péter Antal, Ákos Koós, Hajnalka Füvesi, Péter Portörő, Péter Kesserű, PhD Bay Zoltán Foundation for Applied Research Institute for Biotechnology, Derkovits fasor 2., H-6726 Szeged, Hungary Tel.:+36 62 432 248, e-mail: antpet@baybio.hu ABSTRACT Zero valent iron (ZVI) has been widely used to treat contaminants, like chlorinated hydrocarbons, and it was documented as effective degrading agent of other environmental pollutants. ZVI can reduce halogenated compounds through iron oxidation, however, this process is mainly influenced by the surface of the iron particles. Nano ZVI technology has been developed to maximize the reactive surface of the iron, however, the costs of a treatment process are still quite high and the increased reductive capacity can be toxic. In present work, the combination of the relatively low costs of the traditional ZVI technology and the increased reductive capacity of the nano ZVI technology, avoiding the toxic levels, was tried to be achieved by developing ZVI gels (ZVIG). In up-flow columns filled with the same amount iron (iron powder) in sand (ZVI-P), and gels (ZVIG-A, ZVIG-B), the differences of reduction capacities were determined through nitrate reduction. This process was chosen because of the manageability of nitrate and the fact that ZVI is able to reduce it to ammonia. The column filled with ZVIG-B showed 65 % nitrate reduction from the beginning and maintained this value for 60 days. After the 60th day, a continuous decrease was observed in the efficiency, which reached 10 % after the 160th day. However, ZVIG-A showed 33 % nitrate reduction capacity from the beginning, and the reduction capacity quickly decreased to less than 10 %. After the 15th day, the effectiveness increased rapidly. The same phenomenon could be observed in the ZVI-P column. ZVIG-A could maintain this increased reduction capacity, but the iron powder could not. The nitrate reduction capacity of ZVI-P started to decrease after the 30th day, and it reached 20 % after the 55th day. INTRODUCTION Chlorinated hydrocarbons, especially trichloroethylene (TCE), dichloroethylene (DCE) and vinyl chloride (VC) are produced and utilized in thousands of tons by the industry and agriculture (J.A. Field et al. 2004). These compounds are known as irritable agents and they can be carcinogenic after long exposition time as well. Their degradation in the nature is problematic because of their stability and toxicity. Chlorinated hydrocarbons can accumulate in the soil and can pollute aquifers. Humans can be exposed to them directly via polluted drinking water and via inhaled dust. Since these compounds are drifting in the adipose tissues, it threatens humans indirectly by eating animals exposed to these pollutants. Biodegradation could be a good solution; however, it requires specific bacterium strains that can completely degrade chlorinated hydrocarbons. However, during biodegradation, toxic intermediates can occur which can be harmful to the surrounding living organisms, such as the bacteria used for the degradation process (Johan E. T. et al. 1997).

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Anaerobe abiotic reduction, using zero valent iron is another well-known and favorable process (Comfort S. D. et al. 2001; Shea P. J. et al. 2004). During this process, iron serves as electron donor and the halogenated compounds are the electron acceptors. At the end of the reduction, halogens are switched with hydrogen, and the compounds become less toxic, which makes them more available for the site-born microorganisms. However, this kind of dehalogenisation is connected to the surface of the iron particles, therefore the effectiveness of the reduction depends on the extent of the iron surface. Nano ZVI technology was developed to maximize the reductive surface of the iron. However it had been already documented that the increased reductive capacity can be toxic for Escherichia coli, (Changha Lee et al. 2008) and it could be harmful to the site-born bacteria as well. This property is very unfavorable because these bacteria can facilitate the degradation by using the less halogenated hydrocarbons as energy or carbon source and they can also decrease the concentrations of other alternative electron acceptors. During this study, the different reduction profiles were investigated in constructed up-flow columns via nitrate reduction. This procedure was chosen because nitrate and its reduced forms (nitrite, ammonium) are easier to handle than the chlorinated pesticides. Moreover, it is known that ZVI is able to reduce nitrate to ammonium completely (Yong H. 2004). Therefore, nitrate is an appropriate substrate for the monitoring of the reduction processes. MATERIALS and METHODS Up-Flow column studies Three different column reactors were constructed using 20 ml plastic syringes. The influent was 1 mM KNO3 and HRT= 1 day. Two of the columns contained two different types of zero valent iron gel (ZVIG-A, ZVIG-B). The third column was filled with sand mixed with 1 g of iron powder (ZVI-P). The amount of iron was the same in each column. Samples were taken every day to determine nitrate and nitrite concentration .Three samples were used for each measurement. Measurement of nitrate concentrations 100 µl of 5 gl-1 Na-salicilate was added to the samples, and then they were mixed. The water content of the samples was totally vaporized. After vaporizing, 100 µl c.c. sulfuric acid was added. Then they were diluted with 3 ml distilled water and incubated at room temperature for 10 minutes. After this, 700 µl 10 N sodium hydroxide was added. After complete dissolution, the optical densities were measured with HACH Lange DR5000 spectrophotometer at 410 nm wavelength. Concentrations were determined using a calibration curve. Measurement of nitrite concentrations To 5 ml sample, 100 µl 1 % sulfanilamide (90 ml distilled water, 10 ml c.c. HCl, 1 g sulfanilamide) reagent was added. After a thorough mixing and 5-minute incubation at room temperature, 100 µl of 0,1 % NAD (100 ml distilled water, 0,1 g N-naphthylethylenediamine-dihydrochloride) reagent was added. After total dissolution of the reagents, the optical densities were measured at 540 nm wavelength with HACH Lange DR5000 spectrophotometer. Concentrations were determined using a calibration curve. RESULTS Different reduction profiles of the three different fillings (ZVIG-A, ZVIG-B and ZVI-P) could be determined during a long-term experiment. The results showed significant variance in the nitrate reduction capacity depending on time as shown on Fig. 1.

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Fig. 1. Reductive activities (Nitrate reduction) The column filled with ZVIG-B showed 65 % nitrate reduction from the beginning and maintained this value for 60 days. After the 60th day, a continuous decrease was observed in the efficiency, which reached 10 % after the 160th day. However, ZVIG-A showed 33 % nitrate reduction capacity from the beginning, and the reduction capacity quickly decreased to less than 10 %. After the 15th day, the effectiveness increased rapidly. The same phenomenon could be observed in the column filled with iron powder mixed with sand. ZVIG-A could maintain this increased reduction capacity, but the iron powder could not. The nitrate reduction capacity of ZVI-P started to decrease after the 30th day, and it reached 20 % after the 55th day. Then in the following period, it slowly decreased to less than 10 %. In case of the column filled with ZVIG-A, the reduction capacity started to decrease only at the 80th day and declined to less than 10 % from the 226th day. Nitrite concentrations were also measured in the effluent (Fig. 2.) because this information was important to determine the reductive power of each column and to clear whether nitrate is reducing to nitrite or further. High level of nitrite concentrations should be avoided because it can cause methaemoglobinaemia (Clement A. Finch, 1948). It was found that NO2--N concentration was low in all of the columns compared to the influent NO3--N concentration. However, it seems that both columns filled with ZVIG were more efficient in nitrite reduction than iron powder itself. In columns filled with ZVI-P, nitrite concentration was higher (almost reached 2.5 mgl-1) while nitrite concentrations measured in the effluent of columns filled with iron gel did not reach 2 mgl-1 during the experiments. This indicates that the reduction was faster on the surfaces of the iron particles in the gels than in case of the iron powder, which resulted in less nitrite accumulation.

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2-N (m g/l) NO2--NN Oconcentration (mgl-1)

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2,50 ZVI-P ZVI-P ZVIG-A ZVIG-A ZVIG-B ZVIG-B

2,00

1,50

1,00

0,50

0,00 0

50

100

150 Idő (napok)

200

250

Time (Day)

Fig.2. Reductive activities (Nitrite reduction) CONCLUSIONS • •

Due to the increased reductive surface, reduction capacities of iron gels were increased compared to the same amount of iron powder. Results showed that ZVIG-A and ZVIG-B iron gels had different nitrate reduction profile. ZVIG-B showed high level reductive capacity from the beginning of the experiment, while ZVIG-A reached the nitrate reduction maximum later, but could maintain it for a longer time than ZVIG-B.

LIST OF REFERENCES Changha Lee, Jee Yeon Kim, Won Il Lee, Kara L. Nelson, Jeyong Yoon and David L.Sedlak (2008). Bactericidal Effect of Zero-Valent Iron Nanoparticles on Escherichia coli. Environ Sci Technol. 42(13): 4927–4933 Clement A. Finch (1948) Methemoglobinemia and Sulfhemoglobinemia. M.D.N Engl J Med 239:470-478 Comfort, S.D., Shea, P.J., Machacek, T.A., Gaber, H. and Oh, B.T. (2001). Field-scale Remediation of a Metolachlor-contaminated Spill Site using Zerovalent Iron. Journal of Environmental Quality, 30, 1636-1643 J.A. Field & R. Sierra-Alvarez (2004). Biodegradability of chlorinated solvents and related chlorinated aliphatic compounds. Reviews in Environmental Science & Bio/Technology 3: 185–254 Johan E. T. Van Hylckama Vlieg, WimIM De Koning, and Dick B. Janssen (1997). Effect of Chlorinated Ethene Conversion on Viability and Activity of Methylosinus trichosporium OB3b. Applied and Environmental Microbiology, p. 4961–4964 Shea, P.J., Machacek, T.A. and Comfort, S.D. (2004). Accelerated Remediation of Pesticidecontaminated Soil with Zerovalent Iron. Environmental Pollution, 132, 183-188 Yong H. Huang, Tian C. Zhang (2004). Effects of low pH on nitrate reduction by iron powder. Water Research 38 2631–2642

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EFFECTS OF THE AD LIBITUM CONSUMPTION OF ETHANOL ON THE SERUM LIPIDS METABOLITES AND ON SOME SERUM BIOMETALS STUDIED ON AN ANIMAL MODEL Velciov Petru-Robert1, Garban Gabriela2, Avacovici Adina-Elena1, Velciov Ariana-Bianca3 , Mitroi Mihaela-Elisabeta2 1. Faculty of Industrial Chemistry and Environmental Engineering, University „Politehnica” of Timişoara, Bd.Victoriei Nr.2, RO-300006 Timisoara, Romania; 2. Laboratory of Environment and Nutrition, National Institute of Public Health-Branch Timişoara, Blvd. Dr. V. Babeş Nr.16, RO-300226 Timişoara, Romania; 3. Department of Biochemistry-Molecular Biology, Faculty of Food Products Technology, University of Agricultural Sciences and Veterinary Medicine of Banat, Calea Aradului Nr. 119, RO-300 475 Timişoara, Romania

ABSTRACT Ethanol consumption influences the lipid, electrolyte, carbohydrate as well as the protein metabolisms in humans. Experimental studies with ethanol administration in laboratory animals revealed metabolic changes similar to those in humans. This experimental study was performed on Wistar strain rats divided in three groups: one control C and two experimental ones, i.e. E1 – with occasional alcohol consumption and E2 – with chronic consumption. At the end of the experiment (30 days) the animals were killed and blood samples were collected for biochemical determinations. Serum lipid mtabolites (HDL-cholesterol, LDL-cholesterol, triglycerides) and the concentration of some serum metals (Na, K, Ca, Mg, Fe) were determined. The obtained results showed homeostatic changes with physiological and physiopathological implications. One can conclude that chronic ethanol consumption affects more significantly the serum lipids and metals homeostasis than the occasional one. Key words : occasionally and chronic ethanol consumption – effects in Wistar rats INTRODUCTION Ethanol is rich in calories, poor in nutrients and reduces the absorption of other foodstuff from intestine. Also, ethanol might induce changes the biochemical homeostasis in animals and humans, inducing dyslipidemia and disorders in metals homeostasis. Alcohol consumption, both acute and chronic, has major effects on the absorption, elimination, and serum concentrations of many physiologically important electrolytes and minerals, including sodium, potassium, phosphorus, calcium, magnesium, iron, zinc, and selenium (Friedman etal., 1988; Marsano, 1989; Garban, 1993). Electrolyte disturbances may lead to severe and even life-threatening metabolic abnormalities. The purpose of this investigation was to underline the ethanol effect on the homeostatic status of the lipid metabolism, such as triglycerides and cholesterol fractions (HDL and LDL) and the homeostasis of some serum metals. MATERIALS AND METHODS Chronic ethanol administration was achieved by adding inreasing concentrations

Experimental animal model : Wistar strain rats (males and females) with an average body weight (b.w.) of 150 ± 10 g were divided in three groups: one control (C) and two experimental (E1 and E2). Each group comprised 8 animals ( 4 males and 4 females). Rats of group C consumed tap water. To animals of experimental groups ethanol of 20% concentration (v/v) in the water was administered orally, ad libitum. In animals of group E1 ethanol was administered occasionally, once at four days, during 24 hours. In experimental

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group E2, ethanol was administered permanently in drinking water. On the 30th day of the experiment, after 16 hours of fasting, after Ketanest anesthesia, the animals were killed. Blood samples were taken for analyses after laparotomy and puncture of vena cava caudalis. Analytical determinations : The triglycerides and cholesterol fractions: HDL and LDL were assayed through enzymatic methods, using a Hospitex – Screen Master Plus analyzer. By flamphotometry the concentration of the Na and K and by atomic absorption spectrometry the concentration of Ca, Mg and Fe were determined. Statistical analysis : The obtained data were statistically proceeded, mean value (X), standard deviation (SD) and the statistical significance as the student’s t test were used. RESULTS AND DISCUSSIONS Literature data showes that ethanol causes a significant change in the metabolism of lipids and lipoproteins (Feinman and Lieber, 1999; Daher et al., 2003). Chronic ethanol intake (i.e. several weeks or months in experimental animals) enhances the damaging consequences of these events through a variety of mechanisms. Ethanol promotes oxidative stress, by depletion of oxidative defenses in the cell (Smith, 1991; Lieber, 1999; Hoek and Pastorino, 2002). In clinical chemistry HDL-cholesterol is considered to be a beneficial lipoprotein, its large particles can remove cholesterol from atheroma and has a negative effect on the development of fatty liver (Kono et al., 2001), According to Hannuksela (2004) an increased concentration of HDL-cholesterolemia correlates with lower rates of atheroma progressions and even regression. In pathobiochemisstry elevated concentration of LDL-cholesterolemia promotes atheroma formation on the walls of arteries, a condition known as atherosclerosis, which is the principal cause of coronary heart disease and other forms of cardiovascular disease. Cholesterol plays a central role in many processes, but is best known for the association of cardiovascular disease with various lipoprotein cholesterol transport patterns and high levels of cholesterol in the blood (Stewart at al., 2001). Our results concerning the concentration of lipid metabolites (mg/dL) in serum of Wistar rats are presented in Table 1. Table 1. Concentration of triglycerides, HDL-cholesterol and LDL-cholesterol in blood serum after ethanol administration UM

Triglycerides mg/dL

HDL-cholesterol (mg/dL)

LDL-cholesterol (mg/dL)

8

mg/dL

⎯X ± SD 71.08 ± 10.31

⎯X ± SD 35.13 ± 5.33

⎯X ± SD 22.11±3.59

8

mg/dL

77.50 ± 8.19

50.11 ± 7.12

24.70 ± 4.33

+ 6.42

+ 14.98

+ 2.59

92.83 ± 10.44

53.42± 8.57

34.36 ±8.32

+ 21.75

+ 18.29*

+ 12.25*

Animal groups

n

Group C Group E1 ΔX1 Grup E2

8

mg/dL

ΔX2 n – number of animals

* P < 0.01

From the obtained data, one can observe that trygliceridemia, HDL-cholesterolemia and LDLcholesterolemia are higher in experimental groups as compared to control and the increase is higher in case of chronic administration - E1 compared to occasionally consumption – E2.

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Alcohol has been shown to reduce serum calcium concentrations in several animal studies. The effect of alcohol consumption on serum magnesium concentrations is controversial (Matti Välimäki et al. 1983); some studies revealed an increase and other decrease. In table 2 there are presented the results obtained during this study on the experimental animals. Table 2. Concentration of the investigated metals in the blood serum after ethanol administration Concentration of biometals K Ca Mg (mEq / L) (mg %) (mg %)

n

Na (mEq / L)

C

8

⎯X ± SD 140.72±6.95

⎯X ± SD 4.23±0.41

⎯X ± SD 9.23±0.72

⎯X ± SD 1.85±0.32

Fe (μg %) ⎯X ± SD 94.36±12.15

E1

8

143.17±7.08

4.65±0.48

8.18±0.38

1.91±0.21

98.16±11.02

+ 2.45

+ 0.42

- 1.05

- 0.06

+ 3.80

137.18±3.12

5.39±0.18

8.05±0.30

- 3.54

+ 1.16

- 1.18

Animal groups

ΔX1 E2

8 ΔX2

n – number of animals

1.68±0.06* 111.15±10.24* - 0.17

+ 16.79

* P < 0.01

In animals of group E1 - occasional alcohol consumption, we found an increase of serum sodium, potassium and iron level. Calcemia and magnesiemia showed a mild decrease. In case of chronic administration of ethanol - animals of goup E2 , the results revealed decreased values for sodium, calcium, magnesium while potassium and iron increased. The observed increase is in accordance with other literature data (Matti Välimäki et al., 1983; Friedman et al., 1988; Precob et al., 2000). Literature date state that in adults, alcohol alters iron metabolism predisposing to excess hepatic iron storage and, possibly, liver damage. CONCLUSIONS 1. Studies regarding the concentration of triglycerides and HDL-cholesterol, LDLcholesterol in blood serum of laboratory animals are very important for defining the influence of ethanol consumption on health status. 2. Serum triglycerides concentration is higher in experimental E1 and E2 groups as compared to control, and more precisely, in case of chronic administration (E2) is higher than in occasionally consumption (E1). 3. HDL-cholesterolemia and LDL-cholesterolemia were increased in animals from the experimental groups as compared to control group, i.e. higher in case of chronic administration (E2), revealing the hepatotoxic effect of ethanol 4. Serum metal ions concentration revealed homeostasis changes in animals of E1 group, mild increase of most of the studied metals, excepting calcium. Serum levels of sodium, calcium and magnesium showed a decrease in animals with chronic ethanol administration of E2 group, while the concentration of K and Fe increased.

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REFERENCES 1. Daher C. F., Berberi R. N., Baroody G. M. (2003). Effect of acute and chronic moderate alcohol consumption on fasted and postprandial lipemia in the rat, Food and Chemical Toxicology, 41 (11), 1551-1559. 2. Feinman L., Lieber, C. S. (1999). Ethanol and lipid metabolism. The American Journal of Clinical Nutrition, 70, 791–792. 3. Friedman I.M., Kraemer H.C., Mendoza S.F., Hammer L.D.(1988). Elevated serum iron concentration in adolescent alcohol users. Am.dis.Child, 142(2), 156-159. 4. Garban Z. – Acţiunea alcoolului asupra metabolismului embrio-fetal. pp.139-149, în “Embrio- şi fetopatia alcoolică”, (Editor Sandor S.), Editura Academiei Române Bucureşti, 1993. 5. Kono H., Nakagami M., Rusyn I., Connor H. D., Stefanovic B., Brenner D. A., Mason R. P., Arteel G. E., Thurman R. G. (2001). Development of an animal model of chronic alcohol – induced pancreatitis in the rat, Am. J. Physiol. Gastrointest. Liver Physiol, 280(6), 1178 – 1186. 6. Hannuksela M. L., Rämet M. E., Nissinen A. E. T., Liisanantti M K., Savolainen M.J. (2004). Effects of ethanol on lipids and atherosclerosis, Pathophysiology, 10 (2), 93-103. 7. Hoek J. B. and Pastorino, J. G. (2002). Ethanol, oxidative stress, and cytokine-induced liver cell injury, Alcohol, 27, 63-68. 8. Lieber C. S. (1997). Role of oxidative stress and antioxidant Effects of alcohol on electrolytes and minerals therapy in alcoholic and nonalcoholic liver diseases, Advances in Pharmacology, 38, 601–628. 9. Marsano L. (1989). http://findarticles.com/p/articles/mi_m0847/is_n3_v13/ai_8193360/ 10. Matti Välimäki, Matti Härkönen , Reino Ylikahri (1983). Serum ferritin and iron levels in chronic male alcoholics before and after ethanol withdrawal, Alcohol and alcoholism, 18(3), 255-260. 11. Precob V., Vincu Mirela, Moldovan I., Popa M.G., Gârban Z. (2000). Modificări ale homeostaziei unor bioelemente şi enzime sub acţiunea consumului de alcool etilic, ”Scientifical researches: Agroalimentary Processes and Technologies”, Timişoara, VI, 416-420. 12. Smith L.L., (1991). Another cholesterol hypothesis: cholesterol as antioxidant, Free Radic. Biol. Med., 11, 47-61. 13. Stewart S., Jones, D. and Day, C. P. (2001). Alcoholic liver disease: new insights into mechanisms and preventative strategies, Trends in Molecular Medicine, 7, 408–413.

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OIL EXTRACTION FROM NANNOCHLOROPSIS OCULATA MICROALGAE FOR BIODIESEL PRODUCTION 1

Gog Adriana, 1Roman Marius, 1Senila Lacramioara, 2Luca Emil, 3Paizs Csaba, 3Irimie Florin-Dan

1

INCDO-INOE 2000 Research Institute for Analytical Instrumentation - ICIA, 67 Donath St. 400293 Cluj-Napoca, Romania, adriana.gog@icia.ro 2 University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, Romania 3 Babes-Bolyai University Cluj-Napoca, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos St., Cluj-Napoca, Romania. ABSTRACT Microalgae, the third generation biodiesel feedstock, have emerged as one of the most promising alternative sources of lipids that can be used in the production of biodiesel due to their advantages over conventional crops. Oil extraction is particularly important because this process is one of the more costly processes which can determine the sustainability of algaebased biodiesel. In this paper several methods have been tested for oil extraction from Nannochloropsis oculata microalgae: static hexane extraction, static hexane-isopropanol extraction, dynamic hexane extraction (Soxhlet). The lipid yield for each method was compared with the total lipid content determined using the combination of microwaves with chloroform-methanol extraction. INTRODUCTION Biodiesel is a mixture of monoalkyl esters of long-chain fatty acids obtained in the transesterification reaction of vegetable oils or animal fats with short chain alcohols. The cost of biodiesel production remains the major obstacle to its use at industrial scale, primarily because of the high cost of vegetable oils used as feedstocks [1]. Another important reason is the inefficiency and unsustainability of first and second generation biodiesel [2]. Microalgae, the third generation biodiesel feedstock, have emerged as one of the most promising alternative sources of lipids that can be used in the production of biodiesel due to their advantages: photosynthetic efficiency, high biomass production, higher growth rates and productivity when compared to conventional crops [3]. Microalgal biomass processing for biodiesel production consists in: oil extraction, oil transesterification, biodiesel separation and biodiesel purification. First microalgae are dried and grinded and then subjected to the extraction process to obtain algal oil. After extraction, the oil is converted into biodiesel using the transesterification process. The final stages are the separation and purification of biodiesel product. Although all these steps are essential, the lipid extraction is particularly important because this process is one of the more costly processes which can determine the sustainability of algae-based biodiesel. Different procedures can be applied for extracting oil from microalgae, those being mechanical pressing, homogenization, milling, solvent extraction, supercritical fluid extraction, enzymatic extractions, ultrasonic-assisted extraction and osmotic shock. Solvent extraction involves extracting oil from microalgae by repeated washing or percolation with an organic solvent. Hexane is a popular choice due to its relatively low cost and high extraction efficiency. An increased efficiency of lipid extraction can be achieved by using appropriate methods of cell disruption to release cellular contents into the extraction medium. Numerous methods

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have been used for cell disruption, such as microwaves, ultrasonic, mechanical crushing [4]. For example, the use of microwaves proved to be an effective method for the extraction of vegetable oils [5], while ultrasonic disruption is widely used for microbial cells [6]. In this paper several methods have been tested for oil extraction from Nannochloropsis oculata microalgae: static hexane extraction, static hexane-isopropanol extraction, dynamic hexane extraction (Soxhlet). The lipids were gravimetrically quantified for each method and compared with the total lipids that were extracted using the combination of microwaves with solvent extraction. MATERIALS and METHODS Materials Nannochloropsis oculata microalgae were purchased from Astaxa GmbH (Germany Milz Gerbergrasse). Hexane, isopropanol, chloroform and methanol were purchased from Merck (Darmstadt, Germany) and were of highest purity. Static hexane lipid extraction For static hexane lipid extraction, a quantity of 4 g microalgal powder was used. A volume of 300 mL n-hexane was added to the microalgal powder in a 500 mL Erlenmeyer flask. In order to reduce solvent evaporation, the flask was sealed with a ground joint. The extraction mixture was agitated at 800 rpm at ambient conditions for 8 h. After extraction cell residues were removed by filtering through Whatman GF/C paper. The hexane phase was collected in a pre-weighed flask and then submitted to vacuum evaporation using a rotational evaporator to enable gravimetric quantification of the lipid extract. Static hexane-isopropanol lipid extraction For static hexane-isopropanol extraction a volume of 300 mL mixture of hexane/isopropanol 3:2 v/v was added to 4 g of microalgal powder into a 500 mL Erlenmeyer flask. The flask was sealed with ground joint and the mixture was agitated at 800 rpm at ambient conditions for 8 h. After extraction cell residues were removed by filtering through Whatman GF/C paper. The filtrate was transferred into a separating funnel and a volume of 50 mL hexane and 50 mL water were added to induce biphasic layering. After settling, two distinct phases were formed: a dark-green top layer of hexane that contains most of the extracted lipids and a light-green bottom layer of isopropanol-water mixture containing most of the co-extracted non-lipid contaminants. The hexane phase was collected in a pre-weighed flask and then submitted to vacuum evaporation using a rotational evaporator to enable gravimetric quantification of the lipid extract. Dynamic hexane lipid extraction The performance of static hexane extraction with dynamic hexane extraction was compared using a Soxhlet apparatus. A quantity of 4 g microalgal powder was packed in a cellulose thimble inside the extraction chamber of the Soxhlet unit. A volume of 300 mL n-hexane was used to extract the lipid and the extraction was performed for 8 h at the rate of approximately 10 refluxes per hour. The extracted lipid collected in a pre-weighed flask and then submitted to vacuum evaporation using a rotational evaporator to enable gravimetric quantification of the lipid extract. Microwave lipid extraction A quantity of 0.5 g dry microalgae biomass was mixed with 20 ml distilled water. The mixture was further subjected to cell disintegration using a Speedwave MWS Berghof microwave digester (2450MHz) at 100 °C for 5 min. Total lipids were extracted from microalgae biomass using a modified version of Bligh and Dyer method [7]. Lipids were extracted with a mixture of chloroform-methanol 2:1 (v/v). The volume ratio of biomass

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subjected to the extraction and the organic solvent mixture is 1:1. The mixture was subjected to stirring for 5 minutes in a separating funnel. After extraction the mixture was introduced over a further 10 ml of methanol to separate the two phases: aqueous and organic. The chloroform organic phase was washed with 10 ml 5% sodium chloride and then submitted to vacuum evaporation using a rotational evaporator to enable gravimetric quantification of the lipid extract. RESULTS In order to compare the efficiency of lipid extraction methods used for Nannochloropsis oculata microalgae, the lipid yields obtained for each method were compared to total lipids extracted using the combination of microwaves with chloroform-methanol extraction. A summary of the results is given in table 1. . Table 1. Lipid yield using several methods for lipid extraction from Nannochloropsis oculata microalgae Dynamic Microwave cell Static hexane Static hexanedisruption – extraction extraction isopropanol solvent extraction (Soxhlet) extraction (total lipids) Lipid yield (g 0.136 0.219 0.190 0.328 lipid /g dried microalgae It can be seen that the combination of microwaves with chloroform-methanol extraction gave the higher yield of 0.328 g/g dried microalgae, which is in fact the total lipid content. But for microalgal biodiesel production the ideal lipid extraction method should not only be lipidspecific – in order to minimize co-extraction of non-lipid contaminants, but also selective – towards only a few lipid fractions, e.g. neutral lipids like triacylglycerols [8]. Even though the classic chloroform-based lipid extraction protocol is particularly suitable for most microalgal lipid analyses, alternative organic solvents that are less toxic are preferred prior to scale-up. Hexane is less efficient than chloroform for extraction of oils from microalgae, but is also less toxic – and has a marginal affinity for non-lipid contaminants, and an apparently higher selectivity for neutral lipid fractions [8]. This is why hexane was chosen for oil extraction from Nannochloropsis oculata microalgae, together with the effect of isopropanol addition. Soxhlet extraction with hexane was found to be significantly more efficient than static hexane extraction, with a lipid yield of 0.190 g/g dried microalgae comparatively to only 0.136 g lipid/g dried microalgae for static hexane extraction. This improvement was expected since Soxhlet operation, through solvent refluxing, constantly exposed a fresh batch of hexane to the microalgae biomass and enabled continuous re-establishment of mass transfer equilibrium [9]. In the same time Soxhlet extraction was a little less efficient than the hexane-isopropanol extraction in static mode that gave a lipid yield of 0.219 g/g dried microalgae. With the addition of isopropanol as co-solvent the final lipid yield substantially increased. The reason is that polar lipids (phospholipids, glycolipids, and cholesterols) that are bound to protein molecules in the cell membrane via hydrogen or strong electrostatic bonds, in the presence of a polar solvent (such as isopropanol) are detached from the complex lipid–protein interactions before they are extracted out by hexane. Additionally, even though non-polar

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hexane readily interacts with neutral lipid molecules, the micelle-type structures that triacylglycerols frequently form in their natural state prevent quantitative lipid extraction and often require the assistance of an alcohol for their rapid destruction [10] CONCLUSIONS • From the methods that have been tested for oil extraction from Nannochloropsis oculata microalgae, Soxhlet extraction with hexane was found to be significantly more efficient than static hexane extraction. • The addition of isopropanol as co-solvent for the lipid extraction in static mode determined a substantially increase of lipid yield when compared to static hexane extraction and gave the highest lipid yield. ACKNOWLEDGMENTS This work was financially supported by NUCLEU Program of National Authority for Scientific Research from Romania, Project PN 09 27/2009/OPTRONICA III LIST OF REFERENCES [1]

Lang X., Dalai A.K., Bakhshi N.N., Reaney M.J., Hertz P.B. (2001). Preparation and characterization of bio-diesels from various bio-oils. Bioresource Technology. 80, p. 53–62. [2] Balat M., Balat H. Progress in biodiesel processing. (2010). Applied Energy. 87, p. 1815–35. [3] Minowa T., Yokoyama A-Y., Kishimoto M., Okakurat T. (1995). Oil production from algal cells of Dunaliella tertiolecta by direct thermochemical liquefaction. Fuel. 74(12), p. 1735–8. [4] Prabakaran P. Ravindran A.D. (2011). A comparative study on effective cell disruption methods for lipid extraction from microalgae, Letters in Applied Microbiology. 53, p. 150–4. [5] Cravotto G., Boffa L., Mantegna S., Perego P., Avogadro M., Cintas P. (2008). Improved extraction of vegetable oils under high-intensity ultrasound and⁄or microwaves, Ultrasonic Sonochemistry, 15, 898–902. [6] Lee S.J., Yoon B.D. Oh H.M. Rapid method for the determination of lipid from the green alga Botryococcus braunii, Biotechnology Techniques, 12, p. 553–6. [7] Bligh, E.G., Dyer, W.J. (1959). A rapid method of total lipid extraction and purification. Canadian Journal of Physiology and Pharmacology. 37, p. 7. [8] Amaro H.M., Guedes A.C., Malcata F.X. (2011) Advances and perspectives in using microalgae to produce biodiesel. Applied Energy. 88, p. 3402-10. [9] Wang L., Weller C.L. (2006). Recent advances in extraction of nutraceuticals from plants. Trends in Food Science and Technology. 17, p. 300–312. [10] Medina A.R., Grima E.M., Gimenez A.G., Ibanez M.J. (1998). Downstream processing of algal polyunsaturated fatty acids. Biotechnology Advances, 16, p. 517–580.

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REZALIM-ICIA’S METHOD FOR DETERMINATION OF PAHS FROM WATER SAMPLES A. Naghiu1,2, D. Simedru1, M. Miclean1, L. Senila1, M. Roman1, C. Laslo2 1I

NCDO-INOE2000, Research Institute for Analytical Instrumentation, ICIA Cluj-Napoca Subsidiary, 400293 Cluj-Napoca, Romania 2 University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 ClujNapoca, Romania

ABSTRACT Polycyclic aromatic hydrocarbons (PAHs) are a class of pollutant chemical compounds consisting of fused aromatic rings with great impact on human health and environment. A modern method for determining these pollutants from water at nanoscale level was developed in REZALIM-ICIA laboratory using an HPLC-FLD instrument. The column, its temperature, the mobile phase and the excitation and emission wavelengths were optimized in order to achieve the proposed goal. Calibration curves for each compound were obtained in 5-60 ng/ml concentration range. The method was tested on spiked samples and the results proved to be satisfying. INTRODUCTION Polycyclic aromatic hydrocarbons are formed as a result of burning of organic material and naturally as a result of thermal geological reaction [1, 2]. These compounds are hydrophobic and have low water solubility leading to their persistence in the environment [2, 3]. Polycyclic aromatic hydrocarbons are undergoing degradation through chemical oxidation, photolysis and microbial action; the last is the most efficient [4]. The European Environment Agency as well as other Environmental Protection Agency have listed 16 PAHs as priority pollutants because of their toxicity, mutagenicity and carcinogenic properties [5-7]. Because they have such negative impact on the environment and especially human health a sensitive method for analyzing these extremely dangerous pollutants at nanoscale level is of great interest. MATERIALS and METHODS Reagents and standards PAH Calibration Mix containing 10µg/ml of each compound (Naphthalene, Acenaphthene, Fluorene, Phenanthrene, Anthracene, Fluoranthene, Pyrene, Benz[a]anthracene, Chrysene, Benzo[b]fluoranthene, Benzo[k]fluoranthene, Benzo[a]pyrene, Dibenz[a,h]anthracene, Benzo[ghi]perylene, Indeno[1,2,3-cd]pyrene) in Acetonitrile was acquired from Supelco. Acetonitrile Chromasolv gradient grade for HPLC (purity ≥99.9%) was acquired from Sigma – Aldrich. The ultra-pure water was obtained with a Milli-Q water purification system from Millipore.

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Liquid chromatography conditions The method was developed using a Perkin Elmer 200 Series High Performance Liquid Chromatograph (HPLC) with UV and FLD detectors. 20µL sample volumes were injected using a manual injection system into the system. For separation, a ZORBAX Eclipse PAH 5µm, 4.6×150 mm column from Agilent Technologies was used. The column was kept during the analysis at 25°C. The mobile phase was formed from water (A) and Acetonitrile (B) in variable proportions. The UV detector was set at 254 nm and the FLD detector was set at different wavelenghts appropriate for each compound. Preparation of standards and samples A stock solution of 200 ng/ml was prepared from an ampoule of PAH Mix. The standard solutions for calibration curves were made in dark glass volumetric flasks of 5 ml using 2 pipettes of 1 and 5 ml. The working standards for calibration curves were developed in Acetonitrile at a 5-60 ng/ml concentration range. A spiked sample of 50ng/ml concentration was extracted by liquid – liquid extraction method according to SR EN ISO 17993 [8]. RESULTS In order to obtain the retention times for each compound, a standard solution of 100ng/ml was injected into the system using a mobile phase of A/B 50:50 v/v. The retention times of the compounds were established using the UV detector set at 254 nm. For obtaining a good separation of the compound and a shorter method the flow rate was set at 1.6 ml/min. Starting from these parameters a gradient of mobile phase was developed (Table 1). The elution of PAHs takes place in steps 1 to 5. The 6th and 7th steps assure the cleaning and the reconditioning of the column. The optimal value of the thermostat’s temperature was determined to be 25°C. A 6 steps wavelength program was developed for the FLD detector (Table 2). Using this method a solution of 50ng/ml standard solution was injected into the system and the obtained chromatogram is presented in Figure 1.

Figure 1. Chromatogram of 50 ng standard solution by HPLC using the FLD detector

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Table 1. HPLC gradient program for PAHs determination No.

Time (min.)

Flow (ml/min)

Water A (%)

Acetonitrile B (%)

Step 1

1

1.6

55

45

Step 2

5

1.6

40

60

Step 3

15

1.6

10

90

Step 4

4

1.6

0

100

Step 5

2

1.6

0

100

Step 6

6

1.6

55

45

Step 7

17

1.6

55

45

Table 2. HPLC wavelengths program for PAHs determination Compound 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

*

13. 14.

Naphthalene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benz[a]anthracene Chrysene Benzo[b]fluoranthene Benzo[k]fluoranthene Benzo[a]pyrene Dibenz[a,h]anthracene Benzo[ghi]perylene

15.

Indeno[1,2,3-cd]pyrene

Wavelength (nm) Excitation

Emission

Time (min)

Gain*

224

330

0

3

254

402

9.9

3

237

440

10.9

4

270

390

13.4

3

270

390

19.9

4

300

500

27.4

3

Gain order ranges from 1-5 where 1 is the highest and 5 is the lowest.

Using the method developed earlier a spike sample with a 50ng/ml concentration was extracted and injected into the HPLC system. The recovery ranges for each compound are presented in Table 3. Table 3. Recovery range for each of the15 PAHs analyzed No. 1 2 3 4 5 6 7 8 9 10

Compound Naphthalene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benz[a]anthracene Chrysene Benzo[b]fluoranthene

Recovery range (%) [88.3-95.4] [50.9-55.3] [52.4-58.7] [83.3-88.6] [61.1-66.9] [58.4-63.7] [69.4-73.3] [61.7-65.2] [67.4-71.7] [102.3-107.5]

229

Recovery (%) 92.1 53.0 56.6 85.0 63.0 60.0 71.3 64.3 69.1 105.0

The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

No. 11 12 13 14 15

Compound Benzo[k]fluoranthene Benzo[a]pyrene Dibenz[a,h]anthracene Benzo[ghi]perylene Indeno[1,2,3-cd]pyrene

Recovery range (%) [75.4-80.1] [84.9-88] [65.2-69.1] [64.4-69.7] [82.4-86.7]

Recovery (%) 78.3 86.3 67.6 66.9 84.3

CONCLUSIONS • • •

The HPLC-FLD method developed in REZALIM-ICIA laboratory allows the determination at nanoscale level of 15 prioritary PAHs. The instrument parameters were optimized in order to obtain the best selectivity and sensitivity. The method is used in REZALIM-ICIA laboratory for environmental pollution assay.

LIST OF REFERENCES [1]

Food Standards Agency. (2005). PAHs in dietary supplements, Food Survey Information Sheet. 86/05. [2] Emilie Bamard, Cécile Bulle, Louise Deschênes. (2011) Method development for aquatic ecotoxicological characterization factor calculation for hydrocarbon mixtures in life cycle assessment. Environmental Toxicology and Chemistry. Vol. 30, Issue 10, p. 2342–2352. [3] Guochun He, Bin Zhao, Michael S. Denison. (2011) Identification of benzothiazole derivatives and polycyclic aromatic hydrocarbons as aryl hydrocarbon receptor agonists present in tire extracts, Environmental Toxicology and Chemistry, Vol. 30, Issue 8, p. 1915–1925. [4] Robert A. Kanaly, Shigeaki Harayama. (2010). Advances in the field of high-molecularweight polycyclic aromatic hydrocarbon biodegradation by bacteria, Microbial Biotechnology. Vol. 3, Issue 2, p. 136–164. [5] Yan-Shen Shan, Jung-Hua Fang, Ming-Derg Lai, Meng-Chi Yen, Pin-Wen Lin, HuiPing Hsu, Chian-Yuh Lin, Yi-Ling Chen. (2011). Establishment of an orthotopic transplantable gastric cancer animal model for studying the immunological effects of new cancer therapeutic modules, Molecular Carcinogenesis, Vol. 50, Issue 10, p. 739– 750. [6] Mi-Kyung Song, Youn-Jung Kim, Mee Song, Han-Seam Choi, Yong-Keun Park, JaeChun Ryu. (2011). Polycyclic aromatic hydrocarbons induce migration in human hepatocellular carcinoma cells (HepG2) through reactive oxygen species-mediated p38 MAPK signal transduction, Cancer Science, Vol. 102, Issue 9, p. 1636–1644. [7] Vladimír Kummer, Jarmila Mašková, Zdeněk Zralý, Martin Faldyna. (2011). Ovarian disorders in immature rats after postnatal exposure to environmental polycyclic aromatic hydrocarbons, Journal of Applied Toxicology, Early View (Online Version of Record published before inclusion in an issue). [8] SR EN ISO 17993:2004, Calitatea apei. Determinare a 15 hidrocarburi aromatice policiclice (HAP) în apă prin HPLC cu detecţie prin fluorescenţă după extracţie lichidlichid.

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WOOD – A RENEWABLE RESOURCE FOR PRODUCTION OF SUGAR AND BIOFUEL Lacrimioara Senila, Marin Senila, Adriana Gog, Marius Roman, Miclean Mirela, Levei Erika, Cecilia Roman Research group INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath, 400293, Cluj-Napoca, Romania, e-mail: lacri.senila@icia.ro ABSTRACT Albies Alba wood samples were subjected to autohydrolysis extraction at different severities (180, 190 and 200°C), delignification with sodium chloride, and acid hydrolysis of pretreated and delignified substrates. After autohydrolysis pre-treatment under selected operation conditions, cellulose and lignin, in solid phases, and liquors containing hemicellulose products (monosaccharides, oligosaccharides and inhibitory compounds) have been obtained. The purpose of this study is to obtain glucose by autohydrolysis, delignification and acid hydrolysis of fir wood. Fir wood was pretreated at 180, 190 and 200 °C for 5, 10 and 15 minutes, followed by delignification with sodium chloride and acid hydrolysis. The acid hydrolysis of pretreated material and pretreated-delignified material was hydrolyzed using H2SO4 in two stages of impregnation with acid. The results show that elimination of hemicellulose by autohydrolysis pretreatment and lignin by delignification method improve acid hydrolysis yield. INTRODUCTION Biomass is a great source of energy and has a special attention as a new raw material for biofuels production [1]. Lignocellulosic biomass is a renewable and low-cost resource for production of fuels and many secondary products. Wood is the abundant resource of lignocellulosic biomass, and it is composed from cellulose and hemicelluloses that can be converted in carbohydrates. In addition, agricultural residues, municipal solid waste, industrial solid waste, forestry residues are composed from carbohydrates, which can be further converted into ethanol. Ethanol production from varieties species of wood was studied but is not reported the best species of wood for bioethanol production [2]. Cellulose and hemicellulose could be chemical, biochemical, physic and physico-chemical depolymerized to sugars. Cellulose is a linear polymer formed of long-chain D-glucose monomers, hemicellulose is a mixture of polysaccharide formed from glucose, mannose, galactose, xylose and arabinose and lignin is a three-dimensional polymer of phenylpronane with units of guaiacyl, and syringyl units. Cellulose and hemicellulose can be hydrolyzed to a mixture a pentoses and hexoses [3]. Bioconversion of woody biomass to ethanol consists of four stages: pretreatment, hydrolysis, fermentation and ethanol recovery/distillation. Pretreatment is the most important stage from entire process of conversion because it is a crucial factor for breaking the structure of wood. Various pretreatments were studied including physic, physico-chemical and biological methods. Ecofriendly pretreatment not involve the use of chemical reagents [4].

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Different pretreatment methods for woody biomass were developed. Most of the chemical transformation of wood into components was performed using solvents, requires long processing time and presence of chemicals [5,]. In this study, autohydrolysis pretreatment and acid hydrolysis were performed for glucose production. Autohydrolysis was used for hemicellulose separation in liquid fraction and cellulose (and lignin) recovery in solid fraction. Numerous studies show that elimination of lignin before hydrolysis improve hydrolysis yield [6]. Delignification with sodium chlorite in acetic acid was used for lignin remove before acid hydrolysis. MATERIALS and METHODS Raw material and reagent The raw material used in the experiments was fir wood chips (Albies Alba). All chemicals were analytical reagent grade. Sodium chloride (80%) was purchased from Alfa Aesar (Germany). Acetic acid, sulphuric acid (98%), dicloromethane, ethanol were purchased from Merck (Darmstadt, Germany). Autohydrolysis experiments The mixture of wood and water was homogenized at the desired proportions (7 kg/kg dry solid) and reacted in a pressurized reactor (Parr Instrument) at 180, 190 and 200 °C for 5, 10 and 15 minutes. The pretreated material was separated by filtration into solid and liquid phases. Delignification method Pretreated material resulted after autohydrolysis pretreatment was delignified with sodium chlorite. The samples was treated with NaClO2 in acetic acid 10%, at 70 °C for 1 h (repeated for three times) according to Sun method [7]. Acid hydrolysis Acid hydrolysis experiments of solid fraction recovered after delignification of wood were carried out in 100 ml conical flasks containing 2% H2SO4 at 130°C for 60 min while the second step for cellulose hydrolysis was performed using 15% H2SO4 at 130°C for 90 min. After the hydrolysis process, liquid fractions are separated from unreacted solids and can be subjected to fermentation to bioethanol. The amount of acid used for cellulosic fraction hydrolysis was 38 g of sulfuric acid to 2 grams of dry solid. Analytical methods The moisture content of raw material was determined by the weight loss after drying (105°C, 12 h). Determination of ash in fir has expressed as the percentage of residue remaining after dry oxidation of raw material at 590°C. Extractives were analyzed by extracted by using one step extraction process which includes ethanol an extractive solvent. The chemical content of wood was determined according to Teramoto method [8]. The concentration of reducing sugars was determined according to Miller method [9]. The concentration of hemicellulosic fraction was determined according to our method (Senila 2011) [10]. RESULTS The content of wood was determined and is show in Table 1.

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Table 1. Chemical composition of fir wood comparatively with other compositions of softwood reported in literature Wood species

Hollocelulose

Fir wood –present study Fir wood Douglas fir Albies balsamea) Picea glauca Tsuga canadensis Tsuga occidentalic Pinus nigra

69,99 65,20 69,00 69,00 68,50 64,00 67,00 60,50

Cellulose

Hemicelulose

46.00 ± 0.70

23.99 ± 0.60

42,00 42,00 42,00 42,00 41,00, 41,00 49,50

21,20 27,00 27,00 26,50 23,00 26,00 11,00

Lignin 28.38 ± 0.30

Extractible

Ash

1.31 ± 0.10

0.32 ± 0.10

2,40 2,50

0,40 0,20

32,00 28,30 29,00 28,60 33,00 31,00 27,20

2,00 1,00 3,00 2,00 2,00

The content of fir wood is similar with other softwood species. Autohydrolysis pretreatment was applied to wood for hemicellulose recovery in liquid fraction. Hemicellulose is a mixture of pentoses (arabinose and xylose) and hexoses (glucose, mannose and galactose). Carbohydrates content from hemicellulose fraction was analyzed for its constituents. The method used for carbohydrates identification was conversion of each sugar into their oximetrimethylsilyl derivatives and analyzed by GC-MS. The chromatograms of mannose and arabinose sugar (examples) analyzed are shown in Figure 1.

(b)

(a)

Figure 1. Examples of GC-MS data from monosaccharide standards: (a) GC-MS chromatogram for a derivatized solution of mannose; (b) GC-MS chromatogram for a derivatized solition of arabinose

50

100 90 80 70 60 50 40 30 20 10 0

Recovery of hemicellulosic sugar (%)

Content of solids (g/100 g pretreated wood)

The content of wood after autohydrolysis method and content of sugars from hemicellulosic fraction are shown in Figure 2.

Lignin Hemicellulose Cellulose

5

10 180°C

15

5

10

15

5

190°C

10

15

200°C

Autohydrolysis conditions

45 40 35 30 25 20

oligomeric sugar

15 10

monomeric sugar

5 0 5

10 180

15

5

10

15

5

10

15

190 200 Autohydrolysis conditions

Figure 2. (a) The content of wood after autohydrolysis treatment; and (b) Hemicellulosic sugar recovery in liquid fraction The cellulosic substrate resulted after delignification method was hydrolyzed into glucose. Acid hydrolysis was performed in all cases with H2SO4, in two stages of impregnation with

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acid (2% concentration of acid in first stages and 15% concentration of acid in second stage). Figure 3 (a and b) shows the acid hydrolysis yields determined from the reducing value. 80 70

50

Hydrolysis yield (%)

Hydrolysis yield (%)

60

40 30

10

20

30 60

10

60 50 40

30

30

60

20

90

10 0

0 5

10 180 °C

15

5

10

15

5

190 °C Autohydrolysis conditions

10

5

15

10 180 °C

200 °C

15

5

10

15

5

190 °C Autohydrolysis conditions

10

15

200 °C

Figure 3. Acid hydrolysis yields, expresses as reducing sugar concentration obtained in the acid hydrolysis, for: (a) 2% acid concentration and, (b) 15% acid concentration CONCLUSIONS Woody biomass can be used as renewable resource for production of sugar. Sugar obtained can be subjected to fermentation for bioethanol production. Autohydrolysis pretreatment was applied for hemicellulose remove in liquid fraction and cellulose and lignin recovery in solid fraction. Delignification method was applied for lignin remove before acid hydrolysis. The results show that elimination of hemicellulose and lignin before acid hydrolysis improve acid hydrolysis yield. LIST OF REFERENCES [1]. Sabiha-Hanim S, Noor MAM, Rosma A. (2011) Effect of autohydrolysis and enzymatic treatment on oil palm (Elaeis guineensis Jacq.) frond fibres for xylose and xylooligosaccharides production. Bioresour Technol, 102, p.1234-1239. [2]. Hu R, Lin L, Liu S. (2010) Dilute sulfuric acid hydrolysis of sugar maple wood extract at atmospheric pressure. Bioresour Technol. 101, p. 3586-3594. [3]. Kamm B, Kamm M, Schmidt M, Starke I, Kleinpeter E. (2006) Chemical and biochemical generation of carbohydrates from lignocellulose-feedstock (Lupinus nootkatensis)—quantification of glucose. Chemosphere. 62, p. 97-105. [4]. Nakagame S, Chandra R.P, Kadla J.F, Saddler J.N. (2011) The isolation, characterization and effect of lignin isolated from steam pretreated Douglas-fir on the enzymatic hydrolysis of cellulose. Bioresour Technol. 102, p. 4507-4517. [5]. Hubbel C.A, Ragauskas A.J. (2010) Effect of acid-chlorite delignification on cellulose degree of polymerization. Bioresour Technol. 101, p.7410-7415. [6]. Söderström J, Pilcher L, Galbe M, Zacchi G. (2003) Two-step steam pretreatment of softwood by dilute H2SO4 impregnation for ethanol production. Biomass Bioenerg. 24, p. 475-486. [7]. Sun J. X., Sun X. F., Zhao H., Sun R. C. (2004) Izolation and characterization of cellulose from sugarcane bagasse. Polymer Degradation and Stability. 84, p. 331-339. [8]. Teramoto Y, Lee S, Endo T. (2008) Pretreatment of woody and herbaceous biomass for enzymatic saccharification using sulfuric acid-free ethanol cooking. Bioresour Technol. 99, p. 8856-8863. [9]. Miller G.L. (1959) Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar. Anal. Chem. 31, p. 426-428. [10]. Senila L, Gog A, Senila M, Roman C, Silaghi-Dumitrescu L. (2011) Analysis of carbohydrates obtained from wood by gas chromatography-mass spectrometry. Rev.Chim . 62, p.149-153.

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SOIL POLLUTION ASSESSMENT IN THE BAIA MARE AREA AFTER PARTIAL CLOSURE OF ORE PROCESSING ACTIVITIES 1

Levei Erika, 1Roman Cecilia, 1Roman Marius, 2 Ponta Michaela, 2Frentiu Tiberiu

1

INCDO-INOE 2000 - Research Institute for Analytical Instrumentation, 67 Donath, 400293 Cluj-Napoca, Romania, email: erika.levei@icia.ro 2 Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos, 400028, Cluj-Napoca, Romania, email: ftibi@chem.ubbcluj.ro ABSTRACT The paper presents the assessment of the soil pollution with Cu, Pb and Zn in the Baia Mare area, historically polluted with metals resulted from mining and processing of non-ferrous ores. Despite the closure of mines and reducing the activity related to ore processing, Baia Mare is still a highly polluted site with Pb, Cu and Zn. The Tessier extraction scheme carried out on soil samples recently collected revealed the residual fraction as dominant for all three metals, followed by the reducible fraction bound to Fe and Mn oxides. The exchangeable fraction, considered as the most mobile fraction and that bound to carbonates, which can be mobilized under acidic conditions, were lower. The presence of the oxidisable metal fraction was also observed. INTRODUCTION Soil pollution with heavy metals is a major environmental problem due to their high toxicity, low biodegradability and cumulative nature. Moreover it represents a serious threat to human health by entering into food chain or by leaching into groundwater (Schulin et al., 2007; Wu et al., 2008; Frentiu et al., 2008). Metals can be distributed among the soil components and associated with them in different ways: ion-exchange, adsorption, precipitation, complexation. Thus, the composition and properties of soil have a wide influence on the mobility, bioavailability and toxicity of metals. Baia Mare was the main mining and ore processing centre in NW Romania, recognized as a “hot spot” in Europe with respect to metal pollution (Cordos et al., 1995; Frentiu et al., 2009; Levei et al., 2009). The main industry of the area developed more than one century ago was based on the processing of non-ferrous ores containing Cu, Pb and Zn. The extracted ores were concentrated at the Flotation Station and processed within the Romplumb and Cuprom plants to produce sulphuric acid and different Cu and Pb products. Currently, the Romplumb lead smelter is operating at reduced capacity, focused on the recovery and refinement of Pb from wastes, while the Flotation plant and Cuprom smelter have been closed since December 2007 and January 2009, respectively. The objective of this study was to assess the soil pollution with Cu, Pb and Zn after the closure of mines and cutback of the ore processing activities, using the Tessier sequential extraction scheme, which offers data about the partitioning of metals on five fractions: exchangeable (EXCH), bound to carbonates (CARB), reducible (RED), oxidisable (OX) and residual (RES).

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MATERIALS and METHODS Sampling In 2010 a number of 30 soil samples were collected from 0–20 cm depth in the vicinity of the Flotation Station (9 samples), Cuprom (9 samples) and Romplumb (12 samples) plants Baia Mare town, NW Romania. The soils were air-dried at room temperature, ground to a fine powder in a tungsten-carbide swing mill and sieved to<90 μm. Sample preparation and chemical analysis Total metal contents in soil were obtained following the mineralisation of 1.0 g soil sample with 10 ml aqua regia. Sequential extraction according to the Tessier scheme was carried out using 2.5 g soil, in order to separate the following five fractions (Tessier et al., 1979). The soluble and exchangeable fraction (EXCH) was extracted with 20 ml of 1M MgCl2 (pH=7.0) for 1h. The carbonates (CARB) were extracted by leaching with 20 ml 1M NaAc (pH=5) for 4h. Metals bound to iron and manganese oxides, representing the reducible fraction (RED) were extracted with 50 ml of 0.04M NH2OH HCl in 25%HOAC (pH=2) at 96 oC for 5.5h. Metals bound to organic matter, representing the oxidisable fraction (OX) were extracted with 12.5 ml of 3.2M NH4Ac for 0.5h, after oxidation with 0.02M HNO3 and 30% H2O2 (pH=2.0) at 85 oC for 2 h. The residual fraction (RES) was dissolved in aqua regia using 7 ml of 10M HCl and 2.3 ml of 15.8M HNO3 on a hot plate for 2 h. All solid/liquid separations were performed by centrifugation at 5000 rpm for 15 min. The supernatant was removed and analysed for metals. For each fraction a blank was subjected to the same procedure. The inductively coupled plasma scanning spectrometer SPECTRO CIROSCCD (Spectro Analytical Instruments Kleve, Germany) was used for the determination of metal contents. The soil pH was determined in a suspension of 1:5 (v/v) soil in 1M KCl. The organic carbon content (OC) was determined by oxidising the organic matter from 0.2 g soil with 5–10 ml of 1.6% (w/v) sulfochromic mixture on a hot plate for 20 min. The excess of chromic acid was titrated with 0.2M Mohr salt solution in the presence of diphenylamine as indicator. RESULTS Values of pH, organic matter and total Cu, Pb, Zn contents are presented in Table 1. Concentrations of metals in the analysed samples varied in a large range. The concentrations of Cu and Pb were the highest in the soil samples from Romplumb, while that of Zn near the Flotation Station. Moreover, the contents of Cu and Pb exceeded the alert levels (AL) for less sensitive soil in all samples, while the median value exceeded the corresponding intervention level (IL) set by the Romanian legislation (MO, 1997).

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Table 1. Contents of total Cu, Pb, Zn, organic carbon and pH values in soil Parameter Sampling site Range Average Median AL IL Flotation (n=9) 4.1-8.3 6.3 5.7 pH Cuprom (n=12) 3.6-8.7 5.1 4.6 Romplumb (n=9) 5.9-7.5 6.7 6.6 Flotation (n=9) 0.46-6.6 3.6 2.9 OC (%) Cuprom (n=12) 0.6-4.7 2.5 1.7 Romplumb (n=9) 1.1-5.3 3.4 3.8 Flotation (n=9) 250-21600 9700 9300 250 500 Cu Cuprom (n=12) 330-31200 5300 720 (mg/kg) Romplumb (n=9) 4200-23100 13400 12300 Flotation (n=9) 1100-36000 13900 10500 250 1000 Pb (mg/kg) Cuprom (n=12) 320-12800 3000 1200 Romplumb (n=9) 17100-99400 45700 36700 Flotation (n=9) 145-58000 25400 15100 700 1500 Zn Cuprom (n=12) 280-11600 2000 540 (mg/kg) Romplumb (n=9) 4400-32700 15500 14700 According to figure 1, the residual fraction (RES) was dominant for all three metals, followed by the reducible fraction bound to Fe and Mn oxides (RED). The exchangeable fraction (EXCH) of metals, considered to be the most mobile fraction and that bound to carbonate fraction (CARB), which can be mobilized under acidic conditions, were found in lower percentages. The presence of the oxidisable (OX) metal fraction was also observed. Copper

Lead

Zinc

Figure 1. Partitioning of Cu, Pb and Zn in soils as determined by the Tessier scheme

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CONCLUSIONS The results showed that the pollution of soil persist even after the partial closure of the ore processing activities and under severe environmental conditions the remobilisation of metals retained as carbonates, reducible and oxidisable fractions could occur. LIST OF REFERENCES Cordos E.A., Frentiu T., Rusu A., Vatca G. (1995). Elemental speciation of lead, zinc and copper in sedimented dust and soil using a capacitively coupled plasma atomic emission spectrometer as detector. Analyst. 120, p. 725-731. Frentiu T., Ponta M., Levei E., Cordos E. (2009). Study of partitioning and dynamics of metals in contaminated soil using modified four-step BCR extraction procedure. Chemical Papers. 63, p. 239-248. Frentiu T., Ponta M., Levei E., Gheorghiu E., Kasler I., Cordos E.A. (2008). Validation of the Tessier scheme for speciation of metals in soil using the Bland and Altman test. Chemical Papers. 62, p. 114-122. Levei E., Frentiu T., Ponta M., Senila M., Miclean M., Roman C., Cordos E. (2009). Characterisation of soil quality and mobility of Cd, Cu, Pb and Zn in the Baia Mare area Northwest Romania following the historical pollution. International Journal of Environmental Analytical Chemistry. 89, p. 635–649. MO, 1997. Ministerial Order 956:1997, Official Gazette of Romania, 303/bis/06.11.1997 Schulin R., Curchod F., Mondeshka M., Daskalova A., Keller A. (2007). Heavy metal contamination along a soil transect in the vicinity of the iron smelter of Kremikovtzi (Bulgaria). Geoderma. 140, p. 52-61. Tessier A., Campbell P.G.C., Bisson M. (1979), Sequential extraction procedure for the speciation of particulate trace metals. Analytical Chemistry. 51, p. 844-851. Wu C., Wu J., Luo Y., Zhang H., Teng Y. (2008). Statistical and geostatistical characterization of heavy metal concentrations in a contaminated area taking into account soil map units. Geoderma. 144, p. 171-179.

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APPLYING OF MULTIVARIATE ANALYSIS TO STUDY THE CORRELATION OF MERCURY AND OTHER TRACE ELEMENTS DISTRIBUTION IN SOIL FROM A CITY FROM NW ROMANIA 1

1

Senila Marin, 1Senila Lacrimioara, 1Levei Erika-Andrea, 1Miclean Mirela, 1 Cadar Oana,1Roman Marius, 2Oprea Gabriela, 1Roman Cecilia

INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath, 400293, Cluj-Napoca, Romania, e-mail: marin.senila@icia.ro 2 Faculty of Sciences, North University of Baia Mare, Victoriei 76, 430122 Baia Mare, Romania

ABSTRACT The mercury (Hg) concentrations were evaluated in soils and perennial plants from four districts of Baia Mare city, a historical mining and ore processing center from NW Romania. The results showed that in 24% of the analysed soil samples the mercury concentrations exceeded the guideline value of 1.0 mg kg-1, established by the Romanian Legislation, while the median concentration was 0.70 mg kg-1, bellow the guideline values, but higher than the normal values for soil and the mean or median concentration in soils from other cities all over the world. In the perennial plants, the median concentration was 0.22 mg kg-1, value that exceed the maximum level of Hg (0.10 mg kg-1) established by European Directive 2002/32/EC for animal feed in order to prevent its transfer and further accumulation in the higher levels of food chain. Poor correlations were found between Hg and other elements such as As, Cd, Cu, Pb and Zn known as pollutants resulted from non-ferrous smelting activities, probably due to the different physicochemical properties of Hg that lead to a different dispersion patter compared to other metals emitted by the two smelters. INTRODUCTION Mercury is toxic even in very low concentrations and is considered as one of the most dangerous pollutants, being included in the list of priority dangerous substances established by international environmental legislation (Leopold et al., 2010). The Hg contents in soil are generally low, ranging between 0.01 - 0.2 mg kg-1, with a median of 0.05 mg kg-1 (Rodrigues et al., 2006). The Hg emission sources can be both natural and anthropogenic. The anthropogenic sources are estimated at approximately 6×106 kg year-1 and are represented by the production of pure mercury by industrial processes, combustion of fossil fuels, chemical industry, waste incineration and smelting and refining of non-ferrous metals (Han et al., 2006). Non-ferrous metals (Pb, Cu, Au, Ag, Zn) were extracted and processed in Baia Mare region, NW Romania since ancient times, leading to a historical pollution with Pb, Cu, Zn, Cd and As (Senila et al., 2011). The smelting of non-ferrous metals is known as a source of Hg emission, due to the presence of Hg both in minerals and in the coal used in the smelting processes (Chen et al., 2010). However, no data was found in the literature regarding Hg levels in the Baia Mare area. The aims of this study was to apply the multivariate statistical techniques in order to study the relationships between Hg in soil and plants, and between the contents of Hg, As, Cd, Cu, Pb, Zn and the physicochemical properties of soils (pH, Total Organic Carbon (TOC)).

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MATERIALS and METHODS Site Description and Sampling The city of Baia Mare is located in Maramures County, (Northwest Romania), 228 m elevation above sea level. Together with the surrounding peri-urban regions, the city totals 235.7 km2, of which 31.7 km2 are agricultural fields (Levei et al., 2009). The industry developed around the city was based mainly on mining and processing of non-ferrous minerals from the epithermal Pb–Zn(–Cu–Au–Ag) ore deposits. At the end of 19th and beginning of the 20th century in the Eastern part of the city, one Cu and one Pb smelter were operating. In the summer of 2009 a total of 29 surface soil samples and perennial plants (Agrostis, Agropirum repens, Trifolium repens, Urtica dioica) grown on these soils were collected from 4 areas of Baia Mare. The locals use the studied plant species to feed the animals in their households. The samples were collected as follows: samples 1-8 from Ferneziu district (FE) located in the North-Eastern part of the city, in the proximity of the Pb smelter; samples 9-18 from Săsar district (SA), located in the Northern part, close to the mining area; samples 19-24 from the residential area in the Southern part of Baia Mare (BM), samples 25-29 from Tautii Magheraus (TM) in North-Western part of Baia Mare located far from all industrial activities (Fig. 1). The coordinates of the sampling points were recorded with a 310 Magellan GPS.

Figure 1. Sampling points and the main pollution sources from Baia Mare area Instrumentation, Reagents, Standard Solutions and CRMs The direct measurements of Hg from solid samples (soil and plants) were carried out by thermal decomposition cold vapor atomic absorption spectrometry (TD-CV-AAS) using an Automated Direct Hg Analyzer Hydra-C (Teledyne Instruments, Leeman Labs, USA). The As, Cd, Cu, Pb and Zn concentrations were determined by inductively coupled plasma optical

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emission spectrometry (ICP-OES) using the OPTIMA 3500 DV spectrometer (Perkin-Elmer, USA), after aqua regia digestion. Soil pH was measured with a Consort 2000 pH-meter equipped with a pH electrode (Consort, Belgium). Total Organic Carbon (TOC) content was measured by using a multi N/C 2100S analyzer (Analytic Jena, Germany). Ultrapure water obtained by a Milli Q system (Millipore, France) was used for dilutions. 1000 mg L−1 Hg and 1000 mg L−1 As, Cd, Cu, Pb, Zn multielemental standard solutions (Merck, Germany) were used for calibrations. A soil certified reference material SRM 2709 San Joaquin Soil (New York, USA) and two vegetable certified reference materials NCS ZC 85006 Tomato (Beijing, China) and IAEA-359 Cabbage (Vienna, Austria) were used for the quality control of metals determination. RESULTS AND DISCUSSIONS Concentrations of mercury in urban soils and perennial plants in Baia Mare city According to the Romanian legislation, the typical Hg content in soils is 0.1 mg kg-1. The alert and intervention levels for Hg in soils from sensitive areas, set by the Romanian legislation, are 1.0 mg kg-1dw and 2.0 mg kg-1dw, respectively (MO 956, 1997). In the soils from FE district the Hg average concentration (1.09 mg kg-1dw) was higher than the guideline value of 1.0 mg kg-1dw. Moreover, the intervention limit of 2.0 mg kg-1dw was exceeded in one sample. Hg content in plants from this area exceeds the maximum level (0.10 mg kg-1) established by the European Directive 2002/32/EC (EU Directive 2002/32/EC) allowed in animal feed in order to avoid its transfer and further accumulation in the higher trophic levels of food chain. In SA, the contents of Hg in soil were more homogenously distributed than in FE with a mean (1.02 mg kg-1dw) that slowly exceeded the guideline value of Hg for soil. In plants collected from this area, the Hg concentrations ranged between 0.24 – 0.72 mg kg-1dw with an average concentration two times higher than in plants from FE. In the BM and TM districts, the concentrations of Hg in soils were below the alert level. In plants collected from TM, the Hg concentrations were generally below 0.10 mg kg-1dw, while in those from BM and FE they were similar. Multivariate statistics In agreement with other studies (Esteban et al., 2008), the Pearson’s correlation matrix revealed a significant positive correlation between the soil Hg and TOC contents, that can be explained by the role of soils organic carbon in Hg sorption. Significant positive correlations were found between Cu, Pb, Zn, Cd and As. Significant positive correlation between Hg and As contents was found, and can be explained by the low mobility of these elements in soils (Cabrera et al., 2008). The lack of correlation between Hg in soil and plants revealed that the accumulation of Hg in shoots is mainly determined by Hg absorption from the atmosphere, while the uptake from soil is less important. The Hg content in soils and plants did not correlate with the soil pH, suggesting that pH is not the governing parameter for the Hg transfer. The varimax rotated factor loadings of principal components (PCs) for the soil metals contents and physicochemical properties were used. Three PC’s with eigenvalues higher than 1, explains about 80% of the total variance of the system. The first component (PC1) exhibits 41% of the total variance with positive loadings on Cu, Cd, Pb, Zn and As. This factor indicates the strong association of aqua regia extractable Cu, Cd, Pb, Zn and As in soil, related to the pollution caused by non-ferrous mining and processing activities, and reflects the high values of these elements in the proximity of the industrial area of the city. The second component (PC2) explaining 25% of the total variability contains the soil Hg, As, TOC and pH and reflects the different chemical and physical properties of Hg and, partially, As compared to the other metals, and their interactions with TOC.

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The third component (PC3), explaining 13% of the total variability contains the Hg in plants and reflects the Hg transfer in plants by roots and leaves. CONCLUSIONS Our results revealed a moderate pollution with Hg in the Baia Mare urban area, with the average concentrations exceeding the typical values for urban and agricultural areas in the world. The level of Hg concentrations in perennial plants shoots exceeded the maximum Hg level allowed in animal feed. The analyses showed a high level of pollution with Pb, Cu, Zn, Cd and As, especially in areas located in the proximity of active or inactive smelting activities. Despite the fact that the average concentration of Hg in soils from the four studied areas follows the same trend as the other studied metals, the multivariate analysis revealed poor correlations between mercury and the others analysed metals. This finding can be explained by the special physicochemical properties of Hg and by the additional Hg contamination sources. Hg concentration in soil was significantly positively correlated with TOC, expressing the role of TOC on the Hg distribution in soils. No significant correlations were found between Hg in soil and plants. ACKNOWLEDGMENTS This work was carried out with support from the Romanian Ministry of Education and Research, PNCDI II Program (Project CISPPA no. 52157/2008). LIST OF REFERENCES Cabrera, F., Ariza, J., Madejon, P., Madejon, E., Murillo, J.M. (2008). Mercury and other trace elements in soils affected by the mine tailing spill in Aznalcollar (SW Spain). Sci. Total Environ., 390(2-3), p. 311-322. Chen, X., Xia, X., Wu, S., Wang, F., Guo, X. (2010). Mercury in urban soils with various types of land use in Beijing, China. Environ. Pollut. 158(1), p. 48–54. Directive 2002/32/EC of the European Parliament and of the Council of 7 May 2002 on undesirable substances in animal feed Esteban, E., Moreno, E., Penalosa, J., Cabrero, J., Millan, R., Zornoza, P. (2008). Short and long-term uptake of Hg in white lupin plants: Kinetics and stress indicators. Environ. Exp. Bot., 62, p. 316-322. Han, F., Su, Y., Monts, D., Waggoner, C., Plodinec, M. (2006). Binding, distribution, and plant uptake of mercury in a soil from Oak Ridge, Tennessee, USA. Sci. Total Environ., 368(2-3), p. 753–768. Leopold, K., Foulkes, M., Worsfold, P. (2010). Methods for the determination and speciation of mercury in natural waters - a review. Anal. Chim. Acta., 663(2), p. 127–138. Ministerial Order 956:1997, Official Gazette of Romania, 303/bis/06.11.1997 Rodrigues, S., Pereira, M.E., Duarte, A.C., Ajmone-Marsan, F., Davidson, C.M., Grcman, H., Hossack, I., Hursthouse, A.S., Ljung, K., Martini, C., Otabbong, E., Reinoso, R., RuizCortés, E., Urquhart, G.J., Vrscaj, B. (2006). Mercury in urban soils: A comparison of local spatial variability in six European cities. Sci. Total Environ. 368(2-3), p. 926–936. Senila, M., Levei, E., Miclean, M., Senila, L., Stefanescu, L., Marginean, S., Ozunu, A., Roman, C. (2011) Influence of pollution level on heavy metals mobility in soil from NW Romania, Environ. Eng. Manag. J., 10(1), p. 59-64.

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THE EFFECT OF NITROGEN ON MAIN CHARACTERISTICS OF BIODIESEL OBTAINED FROM RAPESEED OIL Marius Roman1, Adriana Gog1, Mircea Chintoanu1, Emil Luca2, Lacrimioara Senila1 1

INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donth, 400293 Cluj-Napoca Romania, 2University of Agricultural Science and Veterinary Medicine, Calea Manastur 3-5, Cluj-Napoca, Romania; email: marius.roman@icia.ro ABSTRACT The paper aims to establish the role of interaction of irrigation regime and nitrogen rates on main biodiesel characteristics and emissions. Four Nitrogen (N) fertilizer rates 0 (N0), 100 (N100), 150 (N150) and 270 (N270) kg/ha, two irrigation regime (non-irrigated (I0) and irrigated at 50% from IUA (I1) were established as feedstock treatments to obtain biodiesel through transesterification with methanol. The experiments were conducted in a randomized complete block design arrangement in split factorial with three replicates. Correlations between irrigation regime and nitrogen rates regarding the biodiesel main characteristics (cetane number, sulfur content and calorifique value) and emissions (carbon monoxide, hydrocarbons, particulate matter, nitrogen oxides) were established. The recorded results show that, except for nitrogen oxides (NOx), the tested emissions are significantly lower than for conventional petroleum based diesel and the main characteristics respect the values of EN 14214 standard. Biodiesel emissions are significantly lower than the emissions from an engine burning normal diesel. INTRODUCTION Continuing near-record oil prices, fears of unaffordable and rapidly depleting sources of fossil fuel and the desire to achieve energy security and mitigate climate change have combined to heighten interest in biofuel production as a cost-effective, alternative source of energy (Biofuel in the European Union; http://www.ebb-eu.org/). Many governments have developed policies meant to promote affordable, alternative energy sources capable of maintaining current energy consumption standards, supporting further economic growth and reducing oil dependency (British Petroleum Company, http://www.thebioenergysite.com). Over the past decades, there has been an increase in effort to reduce the reliance on petroleum fuels for energy generation and transportation and the biofuels represent a true alternative to conventional fuels. Biodiesel has been gaining worldwide popularity being an eco-friendly, alternative fuel elaborated from domestic renewable resources, that runs in diesel engines (Stevens et al., 2004, http://www.biodiesel-intl.com,). One of the most attractive characteristics of the biodiesel is the reducing of greenhouse gas emissions (GHG) and the releasing of toxic pollutants, and its biodegradability (Demirbas, 2006; Demirbas et al, 2006, Fontaras et al, 2010). The present research was undertaken to find information regarding the possible correlations between the raw material (with different rates of N fertilization and irrigation regime) and main biodiesel characteristics: cetane number, sulfur content, calorifique value and emissions (carbon monoxide, CO, hydrocarbons, HC, particulate matter, PM10 and nitrogen oxides, NOx).

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MATERIAL and METHODS A bifactorial experiment was conducted in 2010 at SC COMCEREAL TURDA (460 35` N and 230 47` E, elevation 345 – 493 m above sea level) in Cluj county, Romania. The summary of the experimental factors is presented in Table 1. Experience scheme was realized to ensure the possibility for an uniform allocation and precise measurement of water and has ensured proper isolation of variants in space. Each plot consisted of 2x5 m (10 m2), spaced 3 m apart. Table 1 Summary of the experimental factors Analyzed factors Graduations Factor A I0 –non-irrigated Irrigation regime I1 –irrigated at 50% from IUA Factor B N0 –non-fertilized Fertilization N100 –fertilized 100 N kg/ha + 75 kg /ha P + 20 kg S N150 –fertilized 150 N kg/ha + 75 kg /ha P + 20 kg S N270 –fertilized 270 N kg/ha + 75 kg /ha P + 20 kg S Cultivar: Dexter, a winter variety. One were applied three watering: watering in autumn (emergence and rosette formation): 300 m3/ha, a watering in the spring (flowering period): 400 m3/ha, a watering in summer (fructification): 500 m3/ha (irrigation norm = 1100 m3/ha). Nitrogen dose was administered in three stages: autumn 25%; spring - 60% (out of winter, on frozen ground); after flowering - 15% (after the appearance of the first internode). Foliar fertilization: FOLICARE 17/9/33 + Bor (Kemira), 5 kg/ha. Phasial fertilization: FOLICUR SOLO (Bayer CropScience), 0.5 l/ha. The biodiesel was obtained at INCDO-INOE 2000, ICIA through transesterification with methanol. The main characteristics (cetane number, sulfur content and calorifique value) were determined at Laboratory for biofuel quality certification, CABIO (http://www.icia.ro). The obtained results were compared with the EN 14214 Standard values. The emissions were determined as follows: the biodiesel samples were run on a direct injection engine and tested for emissions with the equipment AF22M - Micro Monitoring Station (Environment SA, France) according to the norms in force (NOx; CO, HC) and PM10 with PDR 1200 (Thermo Andersen, SUA). The recorded values were compared with the emissions of a petroleum diesel sample purchased from PETROM Romania Company. RESULTS The results recorded are presented in Fig. 1-7.

Fig. 1 Cetane number compared with standard value, (EN 14214)

Fig. 2 Calorifique value, biodiesel and petroleum diesel

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Fig. 3 Sulfur content, compared with standard value, (EN 14214)

Fig. 4 Biodiesel CO emission reduction, comparated to petroleum diesel

Fig. 5 Biodiesel Hydrocarbons emission reduction, compared to petroleum diesel

Fig. 6 Biodiesel Particulate matter, PM10, emission reduction, comparated to petroleum diesel

Fig. 7 Biodiesel NOx emission reduction, compared to petroleum diesel The cetane number for biodiesel ranges from 52 (I0xN0) to 62 (I1xN150). The best results are recorded for the agricultural variants I1 x N100 (59) and I1 x N150 (62). The calorifique value for biodiesel ranges from 9300 kcal/kg (I0xN0) and 9650 kcal/kg(I1xN150), comparatively with 10170 kcal/kg for petroleum diesel. The sulfur content has been recorded very good value, it ranges from 3.1 ppm (I0xN270) to 1.4 ppm (I1xN150). About 11 percent of the weight of biodiesel is oxygen (http://www.biodiesel-intl.com). The presence of oxygen in biodiesel improves combustion and therefore reduces hydrocarbon, carbon monoxide, and particulate emissions; but oxygenated fuels also tend to increase nitrogen oxide emissions. Engine tests have confirmed the expected increases and decreases of each tested exhaust component. The carbon monoxide emissions are lower than carbon monoxide emissions from diesel; the recorded values range from 34.5% (I0xN270) to 39.5 % (I1xN150). The exhaust emissions of total hydrocarbons are reduced with 48.8 % (I0xN0) to 52.2 %(I1xN150). The exhaust emissions of particulate matter, PM10, from biodiesel are between 42.3 (I0xN0) and 46.2 (I1xN150) percent lower than particulate matter emissions

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from diesel. The NOX emissions from biodiesel increase range from 2.5% (I1 x N0) to 9.0% (I0xN270). The feedstock influence the biodiesel characteristics, the better variants of rape crop is I1 x N150. The N rate 270 kg/ha has determined an increasing in NOX emissions comparatively to petroleum diesel. The irrigated rape crop recorded better values compared to nonirrigated variants. CONCLUSIONS • Biodiesel emits carbon monoxide, carbon dioxide, oxides of nitrogen, particulate matter and hydrocarbons baut reduced comparatively with petroleum diesel, helping, through reduced pollution, in the safe keeping of the environment and ensuring of human health. • The biofuel obtained is a biodiesel with good characteristics, according to EN 14214 (cetane number, sulfur content and calorific value). • Results show the reductions in biodiesel emissions as follows: carbon monoxide ranging from 34.5% to 39.5; hydrocarbons ranging from 48.8% to 52.2%; particulate matter ranging from 42.3% to 46.9%; and compared to petroleum diesel. However, nitric oxides (NOx) show slight increase ranging from 2.5 % to 9 %. • Reasons for the variations of the emission performance of each methyl ester are associated with the oxygen content and viscosity of the methyl esters, and these properties are resulted from the properties of the feedstock. Biofuels offer a potential source of renewable energy and large new markets for agricultural produce In order for the biodiesel fuel to remain acceptable by the public, more research is warranted to improve the emissions qualities. LIST OF REFERENCES “Biofuels in the European Union – A vision for 2030 and beyond” – Final draft of the Biofuels Research Advisory Council, 2006 British Petroleum Company. BP Statistical Review of World Energy 2008. (2008). London: BP plc; 2008. Demirbas A. (2006). Global biofuel strategies. Energy Educ Sci Technol,17:33–63. Demirbas MF, Balat M. (2006). Recent advances on the production and utilization trends of bio-fuels: a global perspective. Energy Convers Manage, 2006;47:2371–81 Stevens DJ, Wörgetter M, Saddler J. (2004). Biofuels for transportation: an examination of policy and technical issues. IEA Bioenergy Task 39, Liquid Biofuels Final Report 2001– 2003, Paris Fontaras G, Kousoulidou M, Karavalakis G, Tzamkiozis T, Pistikopoulos P, Ntziachristos L, Bakeas E, Stournas S, Samaras Z. (2010). Effects of low concentration biodiesel blend application on modern passenger cars. Part 1: feedstock impact on regulated pollutants, fuel consumption and particle emissions. Environ Pollut. 158(5):1451-60. Epub 2010 Jan 18 European Biodiesel Board: http://www.ebb-eu.org/ http://www.biodiesel-intl.com http://www.thebioenergysite.com

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THE EFFECTS OF IRRIGATION REGIME AND NITROGEN RATES ON RAPESED YIELD Marius Roman1, Adriana Gog1, Mircea Chintoanu1, Emil Luca2, Lacrimioara Senila1 1

INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donth, 400293 Cluj-Napoca Romania, 2University of Agricultural Science and Veterinary Medicine, Calea Manastur 3-5, Cluj-Napoca, Romania; email marius.roman@icia.ro ABSTRACT The paper aims to establish the role of interaction of irrigation regime, and nitrogen rates on rapeseed yield and yield component (number of branches, siliqua number and number of seeds per siliqua). Four Nitrogen (N) fertilizer rates 0 (N0), 100 (N100), 150 (N150) and 270 (N270) kg/ha, two irrigation regime (non-irrigated (I0) and irrigated at 50% from IUA (I1) and one cultivar of winter rapeseed (Dexter) were established. The experiments were conducted in a randomized complete block design arrangement in split factorial with three replicates. Significant positive correlations were established between irrigation regime and nitrogen rates regarding the rapeseed yield and the main morphoproductive characteristics. The achieved results have pointed out that N fertilization and irrigation regime have a positive effect on rape crop. The best results were obtained for I1 x N150. INTRODUCTION As the world reserves of fossil fuels and raw materials are limited, active research interest has been stimulated in nonpetroleum, renewable, and nonpolluting fuels. Biofuels derived from plant sources, appear to be promising future energy sources (http://www.ebb-eu.org/). In this sense, the rapeseed represents one of the most promising resources for biodiesel in Romania. Rapeseed (Brassica napus L.) has some good characteristics such as suitable placement in crop rotation, desirable quality, high value of oil (40 - 45%) and protein (39%) that has changed it to an important crop (Bailey, 1993). In supporting agricultural production for obtaining high yields, the water and fertilizers play a significant role (Chamorro, 2002, Chauhan, 1993). Water is not the only limiting factor for rape crop. Plants often suffer from nutrient (especially nitrogen, N, phosphorus, P, and sulfur, S, deficiencies, which could be exacerbated by climate and environment changes, especially increased water stress due to the close relationships between water and nutrient availabilities (Clark, 1978, Gan, 2007, ). Nitrogen (N) fertilizer plays a crucial role in enhancing rapeseed yield, and because of the great importance of nitrogen for the development of the whole plant, N-deficiency leads very rapidly to reduced and retarded growth and lower yields (Rose, 2008). A high rate of N application increases leaf area development, improves the root system, the number of branches per plant, the number of silique per plant and increases overall crop assimilation, thus contributing to increased seed yield (Bailey, 1993, Rose, 2008). The present research was undertaken to provide basic information on the response of one winter rapeseed cultivars (Dexter) to irrigation regimes and different nitrogen rates, in order to evaluate the effect of these treatments on rapeseed yield and yield components. The experiments, through differential application of irrigation regime and nitrogen rates, aimed at finding the formula of proper fertilization and irrigation regime with practical recommendations for crop in Transylvania Plain. MATERIAL and METHODS

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A three years experiment was conducted in 2008, 2009 and 2010 at SC COMCEREAL TURDA (460 35` N and 230 47` E, elevation 345 – 493 m above sea level) in Cluj county, Romania. The mean annual precipitation was 657.4 mm in 2008, 471.6 mm in 2009 and 799.3 mm in 2010, during the growing season (October to July). The average of temperature was 10.1 °C in 2008, 9.8 °C in 2009 and 9.8 °C in 2010. Before the experiments, the precursory plant was winter barley. The soil texture was chernozem argiloiluvial vertic with a succession of horizons Am-Bty-C. Ohers characteriscs of the soil: pH 6,5 at the surface (0-15 cm), redox potential, EC,: 1,07 DS/m; humus content: 3,06; phosphorus content, P: 29 ppm; Total nitrogen N: 284 ppm, Organic Carbon: 24,3 g/kg. The experiments have been bifactorial, the summary of the experimental factors, during 2008-2010 are presented in Table 1. Experiments have contained a number of three repetitions (n = 3), the number of variants analyzed in experiment was 12 (4 x 3), the total number of experimental plots was 36 (12 x 3). Experience scheme was realized to ensure the possibility for an uniform allocation and precise measurement of water and has ensured proper isolation of variants in space. Each plot consisted of 2x5 m (10 m2), spaced 3 m apart. Table 1 Summary of the experimental factors, Turda, 2008- 2010 Analyzed factors Graduations Factor A I0 –non-irrigated Irigation regime I1 –irrigated at 50% from IUA Factor B N0 –non-fertilized Fertilization N100 –fertilized 100 N kg/ha + 75 kg /ha P + 20 kg S N150 –fertilized 150 N kg/ha + 75 kg /ha P + 20 kg S N270 –fertilized 270 N kg/ha + 75 kg /ha P + 20 kg S The base work of the soil was made with the disk harrow, which realized a good mobilization and aeration of the soil without turning the furrow. The sowing was made in the last decade of August with 65 germinal seeds/m2. The distance between the rows was 18 cm, and the sewing depth was 3 cm. In 2008 there were applied three watering: watering in autumn (emergence and rosette formation): 350 m3/ha, a watering in the spring (flowering period): 300 m3/ha, a watering in summer (fructification): 450 m3/ha (irrigation norm = 1100 m3/ha). In 2009 there were applied three watering: watering in autumn (emergence and rosette formation): 350 m3/ha, a watering in the spring (flowering period): 550 m3/ha, a watering in summer (fructification): 55 m3/ha, (irrigation norm = 1450 m3/ha). In 2010 there were applied three watering: watering in autumn (emergence and rosette formation): 300 m3/ha, a watering in the spring (flowering period): 400 m3/ha, a watering in summer (fructification): 500 m3/ha. Irrigation norm = 1100 m3/ha. Nitrogen dose was administered in three stages: autumn 25%; spring - 60% (out of winter, on frozen ground); after flowering - 15% (after the appearance of the first internode). Foliar fertilization: FOLICARE 17/9/33 + Bor (Kemira), 5 kg/ha. Phasial fertilization: FOLICUR SOLO (Bayer CropScience), 0.5 l/ha. At maturity, plants of 1 m2 in the middle part of each plot were harvested and the numbers of branches per plant, silique per plant, seeds per silique and seeds yield per unit area were recorded. The test were made on variants, the samples were taken from all the three repetitions and were homogenized at the level of every variant. Analysis of variance of the data appropriate to the experimental design and comparison of means at p≤0.05 were done using POLIFACT software and the means were compared by Duncan Multiple Range Test. RESULTS

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The results recorded are presented in Table 2. Table 2 The main morphoproductive characters, determined during 2008-2010 Treatments / Branches Silique number Seeds number Experimental variants (no plants-1) (no plants-1) (no siliqua-1) 2008 6.29 99.17 21.08 I0 7.33 115.50 24.75 I1 5.60 83.17 17.83 N0 6.47 104.17 22.33 N100 7.28 119.17 25.17 N150 7.90 122.83 26.33 N270 2009 4.87 71.42 15.25 I0 5.59 87.00 19.92 I1 4.30 62.17 14.17 N0 4.93 73.83 17.00 N100 5.43 82.33 18.67 N150 5.78 98.50 20.50 N270 2010 5.56 82.58 16.17 I0 6.73 99.50 20.17 I1 4.92 73.83 14.50 N0 5.88 87.67 17.50 N100 6.68 98.00 20.00 N150 7.10 104.67 20.67 N270

Seed yield (kg/ha) 2282.50 3067.67 2066.67 2571.83 2957.50 3104.33 1596.75 2100.17 1473.50 1793.50 2000.00 2126.83 1988.33 2495.67 1798.50 2161.50 2466.83 2541.17

Analysis of variance on data showed that effect of year was significant on all agronomic traits. One has been recorded difference among the results obtained during the three years experiment. In 2008, there was sufficient rain over the year with more rain in June improving crop growth, and good drying conditions in July promoting flower pollination. The lower yield of rapeseed in 2009 was attributed to climacteric conditions, especially in June when rapeseed was in its rapid growth phase. The yield increased with the application of watering. Rapeseed grew well in 2010 under conditions of good rainfall. There was difference in rapeseed yield ant its morphological components between years (Table 2). There are very significant differences between the irrigated and non irrigated variants. The irrigation applied (experimental factor I1) has been determined the increasing of: ♦yield, with: 785.17 kg/ha (34.4 %) in 2008; 503.42 kg/ha (31.5%) in 2009; 507.33 kg/ha (25.5 %) in 2010; ♦number of branches per plant: 1.18 (21.0 %) in 2008; 0.96 (20.7 %) in 2009; 1.18 (21.0 %) in 2010; ♦number of silique per plant: 16.33 (16.5 %) in 2008; 15.58 (21.8 %) in 2009; 16.92 (20.5 %) in 2010; ♦number of seeds per siliqua: 3.67 (17.4 %) in 2008; 1.18 (21.0 %) in 2009; 4.0 (24.7 %) in 2010. Similar trends were observed during the three experiments. The yield and its components have increased together with the N doses (Table 2). The N rates applied have determined, comparatively with the variant nonfertilized, the following increases: N100 ♦yield: 505.17 kg/ha. (24.4 %) in 2008; 320.00 kg/ha (21.7%) in 2009; 363.00 (20.2%) in 2010 ♦number of branches per plant: 0.87 (15.5%) in 2008; 0.63 (14.7%) in 2009; 0.97 (19.7%) in 2010; ♦number of silique per plant: 21.00 (25,2) – 2008; 11.67 (18.8%) in 2009; 13.83 (18.7%) in 2010; ♦number of seeds per siliqua: 4.50 (25.2) – 2008; 2.83 (20.0%) in 2009;3.00 (20.7%)

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in 2010. N150 ♦yield: 809.83 kg/ha (43.1 %) in 2008; 526.50 kg/ha (35.7%) – 2009; 668.33 (37.2%) in 2010; ♦number of branches per plant: 1.68 (30.1%) in 2008; 1.13 (26.4%) in 2009; 1.77 (35.9%) in 2010 ♦number of silique per plant: 36.0 (43.3) in 2008; 20.17 (32.4 %) in 2009; 24.17 (32.7%); ♦number of seeds per siliqua: 7.33 (41.1%) in 2008; 4.50 (31.8%) in 2009; 5.50 (37.9%) in 2010. N1270 ♦yield: 1037.67 kg/ha. (50.2 %) in 2008; 653.33 kg/ha (44.3%) in 2009; 742.67 (41.3%) in 2010 ♦number of branches per plant: 2.30 (41.1%) in 2008; 1.48 (34.5%) in 2009; 2.18 (44.4%) in 2010; ♦number of silique per plant: 39.67 (47.7%) in 2008; 36.33 (58.4%) in 2009; 30.83 (41.8%) ♦number of seeds per siliqua: 8.50 (47.7%); 6.33 (44.7%) in 2009; 6.17 (42.5%) in 2010. According to the date presented on Table 2 the highest values were registered in the fertilization domain N150 – N270. Obviously, increase in plant number of branches leads to increase in silique number in plant and seeds on siliqua, like the obtained results in this study (Table 2) In addition, the recorded results demonstrate that it is necessary to irrigate until seed maturity stage. CONCLUSIONS • Rapeseed yield was favorable influenced by the nitrogen fertilizers and irrigation that were applied, and which had determined the yield increase once with the increase of the N doses. • The number of branches per plant varied between the limits 6.29 – 7.90 in 2008, 4.30 – 5.78 in 2009 and 4.92 – 7.10, depending on the treatment applied. The highest values were recorded for N150 and N270 and I1. • Silique number per plant varied in the range 83.17-122.83 in 2008, 62.17-98.50, in 2009 and 73.8-104.6 in 2010. The best values were obtained for the variants N150 and N270 and I1. • The number of seeds/siliqua in the researched domain had an amplitude between 21.826.33 in 2008, 14.17 – 20.50 in 2009 and 14.50 – 20.67 in 2010, the highest number being registered on for N150 and N270 and I1. • High nitrogen rates favor the development of rapeseed crop; fertilization at the rate 150 kg/ha has increased the yield and yield components of winter oil seed rape. LIST OF REFERENCES Bailey LD, Grant CA, (1993). Fertility management in canola production. Can. J. Plant Sci. 8(2): 651671. Chamorro A.M., Tamagno L.N., Bezus R., Sarandon S.J. (2002). Nitrogen accumulation, partition, and nitrogen-use efficiency in canola under different nitrogen availabilities – Comm. Soil Sci. Plant Anal. 33 (3-4), 493-504 Chauhan AK, Singh M, Dadhwal KS (1993). Effect of nitrogen level and row spacing on the performance of rape (Brassica napus, L). Ind. J. Agron. 37 (4): 851 - 853. Clark JM, Simpson GM (1978). Influence of irrigation and seeding rate on yield and yield components of Brassica napus cv. Tower. Can. J.Plant Sci., 58: 731-737. Gan, Y., Malhi, S.S., Brandt, S., Katepa-Mupondwad, F., Kutcher, H.R., (2007). Juncea canola in the northern Great Plains. Responses to diverse managements and nitrogen fertilization. Agron. J. 99, 1208–1218. Rose, T. J., Rengel, Z., Ma, Q., Bowden, J. W., (2008). Post-flowering supply of P, but not K, is required for maximum canola seed yields. Europ. J. Agron. 28, 371-379. European Biodiesel Board: http://www.ebb-eu.org/

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LEVELS OF POLYCYCLIC AROMATIC HYDROCARBONS IN MONITORING WELLS FROM MUNICIPAL LANDFILL DETERMINED BY SOLID-PHASE MICROEXTRACTION AND GAS CHROMATOGRAPHY/FLAME IONIZATION DETECTION Mirela Miclean1, Adriana Gog1, Erika Levei1, Marius Roman1, Ioan Stefan Groza2 1

INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath, 400293 Cluj-Napoca, Romania, Phone: + 40 264 420590, Fax: + 40 264 42066, e-mail: mirela.miclean@icia.ro 2 University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, 3-5 Manastur St., 400372, Cluj-Napoca, Romania, Phone: + 40 264 596384, Fax: + 40 264 593794, e-mail: isgroza@yahoo.com

ABSTRACT This study reports the levels of 16 polycyclic aromatic hydrocarbons (PAHs) in the monitoring wells from a municipal landfill. The used analytical method for the simultaneous determination of PAHs was the solid-phase microextraction (SPME)–gas chromatography (GC)–flame ionization detection (FID). Total PAHs concentrations in the samples varied between 1.75 and 9.01 µg/l, with benzo[a]pyrene the most predominant species and reflect the spatial distribution of the monitoring wells.

INTRODUCTION Landfilling is the most widespread technology for the treatment of urban solid wastes. The main environmental concern regarding the municipal landfill sites is the landfill leachate, a highly contaminated wastewater with a wide range of chemical contaminants (Žgajnar Gotvajn et al., 2009; Wu et al., 2011). Among the numerous contaminants of the leachate, polycyclic aromatic hydrocarbons (PAHs) are of particular interest due to their high persistency and low degradability in the environment and also their powerful toxicity. For instance, some of the PAHs are carcinogens, mutagens, teratogens and induce estrogenic effects (Song et al., 2006; Amorim et al., 2009; EPA, 2011). This study reports the concentrations of PAHs in five monitoring wells from a municipal landfill, belonging to a city with approximately 140000 inhabitants, situated in the North-Western part of Romania. The samples, collected in triplicate in May 2011 were analyzed using solid-phase

microextraction (SPME) technique coupled with capillary gas chromatography with flame ionization detection (GC-FID). SPME was introduced in 1989 as a solvent-free extraction technique which integrates sampling, clean-up and pre-concentration into a single step. The most widely used format is a silica rod which is coated with a thin film of extraction phase, such as polydimethylsiloxane

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(PDMS). After extraction has taken place, the loaded SPME fiber is easily introduced into an injection port of a GC instrument for thermal desorption (Hutchinson et al., 2007). MATERIALS and METHODS Reagents and materials The mixture standard solution (DE-PROM 16) containing 16 compounds, each at 100 µg/ml was obtained from LGC Standards (Germany). The analytes were: acenaphthene, acenaphthylene, anthracene, benz[a]anthracene, chrysene, benzo[b]-fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene, benzo[ghi]perylene, fluoranthene, fluorene, naphthalene, phenanthrene, pyrene. Toluene and sodium chloride were of analytical grade and provided by Merck (Darmstadt, Germany). The SPME holder and fiber assemblies for manual sampling were provided by Supelco. The fiber coatings assayed was poly(dimethylsiloxane) (PDMS, 100 μm). SPME extraction Fibres were conditioned in the injection port of a gas chromatograph for 1 h according to the manufacturer’s instructions before use. Blank desorptions of the fibre were carried out to ensure no contamination was present both before and during use. SPME extractions were performed by direct immersion of fiber in 20 mL water sample, into 20 mL vial capped with PTFE-coated septa. The analytes were extracted for 45 min at 25°C with 25 w/v% NaCl, according to the method described by King et al., (2004). After the extraction, the fiber was thermally desorbed for 5 min into the glass liner of the gas chromatograph injector at 290°C. GC-FID analysis Analysis was performed by exposing the fibre to an Agilent Technologies GC-FID (6890) with an HP-5 (5% phenyl:95% dimethylpolysiloxane, 30 m x 0.25 mm, 0.25 µm film thickness) fused-silica capillary column. The injector port temperature and the detector were set to 290°C and 300°C, respectively. The GC temperature was programmed as follows: from 50 (2 min) to 300°C at a rate of 6°C/min where it was held for 5 min. The target compounds were quantified by external calibration using mix standard solution diluted in toluene. RESULTS In all the investigated samples, the concentrations of acenaphthylene, chrysene, benzo[b]fluoranthene, benzo[k]-fluoranthene, indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene, benzo[ghi]-perylene, fluorene, naphthalene, phenanthrene were below the detection limits. The limits of detection, determined using the 3σ criteria varied in the range 2 ng/l (for fluoranthene and pyrene) to 36 ng/l (for benz[a]anthracene). Total PAH concentrations in the samples are shown in Table 1 and varied between 1.75 and 9.01 µg/l, with benzo[a]pyrene the most predominant species. Table 1. Total PAH concentrations in the monitoring wells Sample Total PAH concentration, µg/l Sample 1 4.12 Sample 2 3.12 Sample 3 1.75 Sample 4 7.00

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Sample 5

9.01

The concentrations of PAHs in the 5 monitoring wells are graphically shown in Figure 1.

Figure 1. Concentrations of PAHs in the monitoring wells (ng/l) The chromatogram obtained for sample 5, for example, is shown in Figure 2, emphasizing the obtained compounds: acenaphthene, anthracene, fluoranthene, pyrene, benz[a]anthracene and benzo[a]pyrene.

Figure 2. The GC-FID chromatogram of the sample 5 The obtained concentrations reflect the spatial distribution of the monitoring wells related to the underground water flow. In the wells situated upstream and in the side of municipal

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landfill, the PAHs levels are low (samples 1, 2 and 3) due to the fact that underground water collects waters from uncontaminated area. In the wells located downstream of landfill, the concentrations are higher (samples 4 and 5), taking into consideration that underground water collects the landfill leachates. CONCLUSIONS • SPME-GC-FID method is appropriate for a multi-residue analysis of 16 PAHs, included in the list of priority pollutants. • SPME-GC-FID method is suitable for the analysis of water from monitoring wells in municipal landfill sites. • SPME technique could be used for in situ determination, for monitoring the quality of water. • SPME is an interesting preconcentration technique which avoids the use of organic solvents and clean-up steps, reducing the analysis time and costs. LIST OF REFERENCES Amorim, L. C. A., Dimandja, J.-M., de Lourdes Cardeal, Z. (2009). Analysis of hydroxylated polycyclic aromatic hydrocarbons in urine using comprehensive two-dimensional gas chromatography with a flame ionization detector, Journal of Chromatography A. 1216, p. 2900–2904. EPA, 2011, available at: http://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.abstractDetail/abstract/ 173/report/0 Hutchinson, J. P., Setkova, L., Pawliszyn, J. (2007). Automation of solid-phase microextraction on a 96-well plate format. Journal of Chromatography A. 1149, p. 127– 137. King, A. J., Readman, J. W., Zhou, J. L. (2004). Determination of polycyclic aromatic hydrocarbons in water by solid-phase microextraction–gas chromatography–mass spectrometry. Analytica Chimica Acta. 523, p. 259–267. Song, Y. F., Wilke, B.-M., Song, X. Y., Gong, P., Zhou, Q. X., Yang, G. F. (2006). Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals (HMs) as well as their genotoxicity in soil after long-term wastewater irrigation. Chemosphere. 65, p. 1859–1868. Wu, Y., Zhou, S., Ye, X., Chen, D., Zheng, K., Qin, F. (2011). Transformation of pollutants in landfill leachate treated by a combined sequence batch reactor, coagulation, Fenton oxidation and biological aerated filter technology. Process Safety and Environmental Protection. 89, p. 112– 120. Žgajnar Gotvajn, A., Tisler, T., Zagorc- Končan, J. (2009). Comparison of different treatment strategies for industrial landfill leachate. Journal of Hazardous Materials. 162, p. 1446–1456.

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BIODEGRADATION STUDIES OF POLYLACTIC ACID COPOLYMERS Cadar Oana 1, Paul Maria 1, Roman Cecilia 1, Cadar Sergiu 1, Isabela 2, Majdik Cornelia 2

enilă Marin 1, Irsai

1

INCDO-INOE 2000, Research Institute for Analytical Instrumentation, 67 Donath, 400293 Cluj-Napoca, Romania, Tel: +40-264-420590, Fax: +40-264-420667, oana.cadar@icia.ro 2 Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos, 400028 Cluj-Napoca, Romania, Tel: +40-264-593833, Fax: +40-264-590818, majdik@chem.ubbcluj.ro ABSTRACT Medium molecular weight copolymers were synthesized by the condensation of L-lactic acid (LA), terephthalic acid (TPA) and 1,3-propanediol (PDO). The obtained copolymers were characterized for acid value, hydroxyl value and number average molecular weight. Also, the biodegradation behavior by different fungal species (Aspergillus niger, Aspergillus versicolor, Alternaria alternata and Penicillium) was performed. The degree of biodegradation was examined by weight loss. It was observed that the biodegradation of copolymer with higher quantity of lactic acid was faster and more effective than the biodegradation of copolymer with smaller quantity of lactic acid. INTRODUCTION Polymer materials produced from petrochemicals are inert and resistant to microbial attack. Therefore, the degradable and biodegradable polymers are of considerable interest with respect to solid waste accumulation. In the last few years, polyesters have been considered the best candidates to replace traditional polymers because of their potential biodegradability due to their hydrolysable ester bonds. The biodegradability of aliphatic and aromatic polyesters is completely different: (i) aliphatic polyesters are easily susceptible to microbial attack (depolymerization or surface erosion followed by enzymatic hydrolysis resulting soluble intermediates that can be easily assimilated by microbial cells; aliphatic polyesters containing diacids of medium-sized monomers, are more easily degraded by fungi (Aspergillus niger and Aspergillus flavus) than those derived from longer or shorter monomers [1] and (ii) aromatic polyesters are not significantly influenced by the hydrolytic degradation [2, 3]. However, some growth of Aspergillus niger and Aspergillus flavus were observed on the surface of low molecular weight aromatic polyesters [4]. Recently, much progress has been carried out in polylactic acid (PLA), polyglycolic acid (PGA) and their copolymer (PLGA). PLA and PGA and their copolymer can be obtained by following processes: a) ring opening polymerization of cyclic dimers (lactide and glycolide) in the presence of metal/metal compounds catalysts to synthesize high molecular weight polymers and b) direct condensation reaction of lactic acid / glycolic acid to obtain low molecular weight polymers [5-8]. The aim of this work was to synthetize medium molecular weight copolymers of L-lactic acid, terephthalic acid and 1,3-propanediol. The obtained copolymers were characterized for acid value, hydroxyl value and number average molecular weight. Copolymers were biodegraded by four fungal species. Biodegradability studies were performed by weight loss.

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MATERIALS and METHODS All chemicals were of analytical grade (Merck KGaA, Darmstadt, Germany) and used without further purification. The highest available purities were used. L-lactic acid was an 85-90 % (w/w) aqueous solution of monomer, 99% optically pure according to the manufacturer. Molecular sieves were activated at 250 oC for 24 h. Preparation of copolymers Copolymers of L-lactic acid, terephthalic acid and 1,3 propanediol were prepared by direct polycondensation (different ratio of monomers, Table 1). The corresponding quantities of monomers were introduced in a 100 ml three-necked round bottom flask equipped with a Dean Stark trap containing molecular sieves 3 Å. In first stage temperature was kept at 100 ºC for 8 h. The initial white suspension turns into a clear solution. In second stage the reaction was performed at 260 ºC for 12 h and 0.2% SnCl2 · 2H2O was added as a catalyst. After slow cooling of the reaction mixture room temperature, the copolymers were precipitated by addition of deionized water. Precipitated copolymers were collected by filtration and dried under reduced pressure and then white powders were obtained. Table 1. Overview of the synthesis and characterization of the obtained copolymers Hydroxyl Mn*** Copolymer LA (mol) TPA (mol) PDO (mol) Acid value* value** 1.0 0.5 0.5 0.021 0.022 9524 1 0.1 2.0 2.0 0.020 0.025 10000 2 * ASTM D 1639-90 (1996), Standard Test Method for Acid Value of Organic Coating Materials ** ASTM D2840-69(1976) Method of Test for Average True Particle Density of Hollow Microspheres *** Mn = F×100/C (F - functionality of polymer, C - acid value). Characterization The obtained copolymers were characterized for acid value, hydroxyl value, number average molecular weight and biodegradability. Biodegradation studies. Synthesized copolymers were tested for their biodegradability by fungal species. For fungal species were selected for this study: Aspergillus niger, Aspergillus versicolor, Alternaria alternata and Penicillium. 15 ml of patato dextrose agar medium (PDA) was poured in each sterilized Petri dish. On each Petri dish a small quantity of the fungus culture was added. The Petri plates were incubated at 25 °C for 7 days in WTW OxiTop BOD measurement incubator. The growths of fungus were scrapped from Petri plates and introduced into 250 ml Erlenmeyer flasks containing 100 ml sterile distilled water. These samples were incubated at 25 °C for 10, 20, 30, 40, 50 and 60 days. The samples were taken out from the culture media, repeatedly rinsed by a stream of distilled water and dried under vacuum. All experiments were performed in duplicate and average values were reported. Non-inoculated flasks were used as controls and were treated in the same way as the samples. The effect of fungal treatment of copolymers was monitored by weight loss. Weight loss (gravimetrically) was calculated by the following expression: Weight loss =

Weight of sample before degradation - Weight of sample after degradation × 100 Weight of sample after degradation

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RESULTS Synthesis of copolymers Copolymers containing different ratio of L-lactic acid, terephthalic acid and 1,3-propanediol were obtained by polycondensation reaction. The copolymers were obtained as white coloured solids having medium molecular weight. The acid value, hydroxyl value and number average molecular weight are presented in Table 1. Biodegradation by fungal species The degree of biodegradation of copolymers 1 and 2 expressed as weight loss is presented in Figures 1 and 2.

Figure 1. Biodegradation of copolymer 1 by different fungal species

Figure 2. Biodegradation of copolymer 2 by different fungal species The highest biodegradation occurs in the case of Aspergillus niger as compared to other fungal species (83% - 1 and 71% - 2). Also, good results were obtained for Aspergillus alternata (71% - 1 and 68% - 2). The biodegradation of copolymer 1 was higher than copolymer 2 for Aspergillus versicolor (72% - 1 and 47% - 2). In both cases, the least result was obtained by biodegradation by Penicillium (64% - 1 and 62% - 2). Similar results were

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reported by Soni et al. [9]. The weight loss was directly proportional to the content of lactic acid. Accordingly, the degradation rate was faster and more effective in the case of copolymer 1 (LA : TPA : PDO = 2 : 1 : 1, molar ratio) having excess amount of lactic acid than in the case of copolymer 2 (LA : TPA : PDO = 1 : 20 : 20, molar ratio). CONCLUSIONS • The title copolymers were synthesized by the polycondensation of L-lactic acid, terephthalic acid and 1,3-propanediol by using different monomer ratio. • The obtained copolymers were successfully biodegraded by different fungal species (Aspergillus niger, Aspergillus versicolor, Alternaria alternata and Penicillium). • The rate of biodegradation was influenced by the copolymer composition (the biodegradation of 1 is greater due to the presence of higher amount of lactic acid). ACKNOWLEDGEMENT The financial support provided by the Romanian Minister of Education, Research, Youth and Sports, PNCDI II Program (Project BIOPLAST no. 72152/2008) was greatly appreciated. The authors gratefully acknowledge the contribution of Prof. Dr. Carmen Puia, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca for providing microbial strains for this work and for helpful discussions. LIST OF REFERENCES [1] [2] [3] [4] [5] [6] [7] [8] [9]

Müller R.J., Kleeberg I., Deckwer W.D. (2001). Biodegradation of polyesters containing aromatic constituents. Journal of Biotechnology. 86(2), p. 87-95. Levefre C., Mathieu C., Tidjani A., Dupret A., Vander Wauven C. (1999). Comparative degradation by microrganisms of terephthalic acid, 2,6-naphthaence dicarboxylic acid, their esters and polyesters. Polymer Degradation and Stability. 64, p. 9-16. Tokiwa Y., Suzuki T. (1997). Hydrolysis of polyesters by lipases. Nature. 270, p. 7678. Huang C.A., Byrne H.S. (1980). Biodegradable polymers: photolysis and fungal degradation of poly (arylene keto esters), Journal of Applied Polymer Science. 25, p. 1951-1960. Gilding D.K., Reed A.M. (1989). Biodegradable Polymers for Use in SurgeryPolyglycolic/Poly(lactic acid) Homo- and Copolymers. Polymer. 20, p. 1459-1564. Deasy P., Finan M., Meegan M. (1989). Preparation and characterization of lactic/glycolic acid polymers and copolymers. Journal of Microencapsulation. 63, p. 369-78. Fukuzaki H., Yoshida M., Asano M., Kumakura M. (1989). Synthesis of copoly(D,Llactic acid) with relative low molecular weight and in vitro degradation. European Polymer Journal. 25, p. 1019-1026. Fukuzaki H., Yoshida M., Asano M., Aiba Y., Kastsu I. (1998). Synthesis of copoly(d,llactic acid) with relatively low molecular weight and in vitro degradation. European Polymer Journal. 25, p. 1019-1026. Soni R.K., Soam S., Dutt K.(2009). Studies on biodegradability of copolymers of lactic acid, terephthalic acid and ethylene glycol. Polymer Degradation and Stability. 94, p. 432–437.

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PORPHYRIN BASED-SYSTEMS FOR THE DETECTION OF RECOVERABLE METALS FROM Li-ION BATTERIES. MINI-REVIEW Eugenia Fagadar-Cosma1*, Gheorghe Ilia1, Smaranda Iliescu1, Lavinia Macarie1, Nicoleta Plesu1, Adriana Popa1, Gheorghe Fagadar-Cosma2 1

Institute of Chemistry Timisoara of Romanian Academy, 24 M. Viteazul Ave, 300223Timisoara, Romania, e-mail: efagadar@yahoo.com 2 "Politehnica" University of Timisoara, T. Lalescu Street, No. 2, 300223-Timisoara, Romania ABSTRACT The collection and recycling of metals, especially heavy metals, from all types of batteries is a major requirement of European Countries. Market studies highlighted that in the rechargeable battery field, lithium batteries are environmental friendly alternatives to the more polluting Ni–Cd batteries. Although lithium is not expected to bioaccumulate and its human and environmental toxicity are low, one source of lithium with impact to the environment is spent lithium batteries, due to the large variety of Li salts incorporated in polymer electrolyte membranes. Concerning to cathode, new trends are based on nanostructured lithium iron and manganese phosphate. Whatever are the metals involved in the cathode of batteries (Co-NiMn-Fe) the problem of controlling the efficiency of metals recovery is implying the use of sensor devices. In this paper we are concerned on porphyrin –based sensor devices for the rapid and accurate detection of Li, Ni, Mn. INTRODUCTION Because Li based batteries are considered electric energy storage systems characterized by high energy/power density, which is the most important demand of electric vehicles [1] attention is also focused to diminish the negative environmental effects of batteries and waste batteries [2]. In spite of their low content in metals many efforts are concentrating to collect and recycle [3] of all types of batteries. Li- AND OTHER METAL- SALTS INCORPORATED INTO POLYMERIC MEMBRANES AND IN THE CATODE OF THE BATTERIES. Due to their applications in lithium rechargeable battery technology, a large variety of Li salts [4] are studied for being incorporated in polymer electrolytes, such as: LiSbF6, LiF, LiCl, LiBr, LiI, lithium perchlorate (LiClO4), lithium arsenate (LiAsF6), lithium tetrafluoroborate (LiBF4), lithium triflate (LiCF3SO3), and lithium bis(trifluoromethane sulfone)imide (LiN(SO2CF3)2), lithium bis-perfluoroethylsulfonyl imide LiN(SO2C2F5)2. Although the environmental toxicity Li is low, one of the main sources of lithium having impact to the environment is spent lithium batteries [5]. New formulations of cathode are based on nanostructured lithium iron or manganese phosphate. Whatever are the metals involved in the cathode of batteries (Co-Ni-Mn-Fe) the technology to recover different metals will stay feasible as the non ferrous metallurgy for those products is always based on Sulphuric Acid. The sensor devices are more often used for controlling the efficiency of metals recovery. In this paper we are concerned on porphyrin – based sensor devices for the rapid and accurate detection of Li, Ni, Mn due to the fact that porphyrins are forming 1:1 complexes with almost all metals [6].

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PORPHYRIN BASED-SYSTEMS FOR THE DETECTION OF RECOVERABLE METALS FROM Li-ION BATTERIES Li DETECTION. Lithium is the most important element for lithium battery, but also in clinical treatment of depression. Thus, a new goal is finding of inexpensive methods for the determination of lithium and its separation and collection by recycling. Octabromoporphyrin, 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrin, (H2P4−), (Figure 1, structure a), a water-soluble porphyrin, was demonstrated to react with lithium ion in aqueous alkaline solution to form LiP5−, of which formation constant was 10−18.81 ± 0.02 mol dm−3 for KLiP = [LiP5−][H+]2[Li+]−1[H2P4−]−1. Reactions were 103-104 times faster comparatively to more planar unbrominated porphyrin derivatives [7]. This kind of structure is highly electron deficient, producing a decrease of the basicity of porphyrin due to the presence of eight bromine atoms that are attach in the β-pyrrole positions [8]. A spectrophotometric method for the determination of lithium in aqueous solution was also reported, by using the same porphyrin [9]. The calibration graph was linear over the range of 0.007–0.7 mg cm-3 (1x10-6–1x10-4 mol dm-3) of lithium (I) with a correlation factor of 0.967. By this method the determination of lithium as low as 10-5 M in the presence of Na+ greater than 0.1 M could be done. The selectivity of Li+:Na+ is higher than 104 [10]. Mn DETECTION. The determination of manganese in environmental samples is a need because acute exposure to manganese generates chemical pneumonitis and chronic exposure may lead to dementia [11]. The oxidation states of manganese are ranging from −3 to +7, but the most abundant species is Mn2+, followed by Mn3+ and Mn4+. Anodic stripping voltammetry analysis of trace amount of Mn(II) was reported and it is based on chemically modified bentonite– meso-tetra laural porphyrin (Figure 1, structure b) carbon paste electrode. In this method Mn(II) gives well-defined voltammetric peak in the pH range of 3.5–7.5. The detection limit is 1.07×10−7 mol L−1 Mn(II). The peak currents increase linearly with Mn(II) concentration over the range of 6.0×10−7 to 5.0×10−4 mol L−1. The selectivity is very high, so that an excess of 1000-fold of the additive ions had not interferences on the determination of Mn(II). Co DETECTION. PVC-based membranes having as ionophore 5,10,15,20tetraphenylporphyrin together with sodium tetraphenylborate as an anion excluder have been investigated as potentiometric sensors for Co(II) [12]. Calibration graphs were linear from 0.008-100 mM-Co(II) and the response time was 20 s. The membrane was stable for 4 months and showed good selectivity for Co(II) over other cations, although Na(I) and Ni(II) interfered at high concentrations. Ni DETECTION. Due to the fact that the nickel toxicity generates various diseases such as: pneumonitis, dermatitis and asthma, its accurate determination is important. In this respect, more nickel-selective potentiometric electrodes [13, 14] based on two symmetrical different porphyrins as ionophores: meso-tetraphenylporphyrin and meso-tetra-p-tolylporphyrin Table 1, structures c and d) were realized, by varying the nature of solvent mediators and the ratio of of the membrane components. Both of the electrodes exhibit preference to nickel ions, but the silver ion interferes in both of the cases; for the meso-tetra-p-tolylporphyrin based electrode, the lead ions interfere too [14]. It may be concluded that the electrodes have a moderate selectivity. The nickel-selective electrode based on meso-tetraphenylporphyrin as ionophore presents a better potentiometric response comparatively to the meso-tetra-ptolylporphyrin based one, when using the next composition for the membranes: 1 wt.% ionophore, 66 wt.% o-nitrophenyloctylether (o-NPOE), 33 wt.% PVC (plasticizer : PVC = 2 :1) and sodium tetraphenylborate 20%mol. relative to the ionophore. The response was linear in the range (5x10-4 -1x10-1 M). By using another solvent mediator, dibutylphthalate, the best result was given when using the membrane incorporating meso-tetra-p-tolylporphyrin, sodium tetraphenylborate and solvent mediator in PVC in the ratio (7 : 35 : 4 : 54), exhibiting

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Nernstian response in the concentration range 5.6× 10−6–1.0×10−1 mol/l between pH 2.5–7.4 and a fast response time of 20 s [13]. A new membrane, having in composition meso-tetrakis-{4-[tris-(4-allyl dimethylsilylphenyl)-silyl]-phenyl}porphyrin (Figure 1, structure e) [15]: sodium tetraphenyl borate: PVC in the ratio 5:5:150, exhibited Nernstian response in the activity range 2.5×10−6 to 1.0×10−1 M, over wide pH range (2–5.5) with a fast response time (8 s). The sensor can be used in partially non-aqueous media up to 20% (v/v) content of methanol or ethanol and acetone and over a period of 4 months. New trends in finding of suitable analytical methods for metal detection are focused on incorporation of days into hybrid materials, such as silica glasses. The main advantages of this solution is that glasses prepared from the sol–gel process are transparent, making them suitable for spectrophotometric analysis, are chemically, photochemically and thermally stable making them proper for use in harsh environments [16]. A novel metal ion sensor for Zn2+ and Ni2+ was prepared using silica monolith doped with meso-tetra(p-carboxyphenyl) porphyrin (Figure 1, structure f). The doped material was prepared using TEOS:EtOH:H2O:HCl:porphyrin molar ratios of 1:5:7:3.1 x 10-2:2.3 x 10-5, respectively. The metal coordinated to the silica monolith could be removed by washing with 1 M HNO3 [17]. SO3

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e) Figure 1. The structures of ionophores: 2,3,7,8,12,13,17,18 -octabromo-5,10,15,20-tetrakis(4sulfonatophenyl) porphyrin (a); meso-tetra laural porphyrin (b); meso-tetraphenylporphyrin (c)meso-tetra-p-tolylporphyrin; meso-tetrakis-{4-[tris-(4-allyl dimethylsilyl-phenyl)-silyl]phenyl}porphyrin (e); meso-tetra(p-carboxyphenyl) porphyrin (f). ACKNOWLEGEMENTS The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 266090 (SOMABAT).

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LIST OF REFERENCES [1] Corbo P., Migliardini F., Veneri O. (2010). Lithium polymer batteries and proton exchange membrane fuel cells as energy sources in hydrogen electric vehicles. Journal of Power Sources. 195, p. 7849–7854. [2] DIRECTIVE 2006/66/EC OF THE EUROPEAN PARLIAMENT of 6 September 2006 on batteries and accumulators and waste batteries and accumulators and repealing Directive 91/157/EEC, Official Journal of the European Union, L266. [3] Contestabile M., Panero S., Scrosati B.(1999). A laboratory-scale lithium battery recycling process. Journal of Power Sources. 83, p. 75–78. [4] Sanders R.A, Snow A. G., Frech R., Glatzhofer D. T. (2003). A spectroscopic and conductivity comparison study of linear poly(N-methylethylenimine) with lithium triflate and sodium triflate. Electrochimica Acta. 48, P. 2247-2253. [5] Aral H., Vecchio-Sadus A. (2008). Toxicity of lithium to humans and the environment-A literature review. Ecotoxicology and Environmental Safety. 70, P. 349– 356. [6] Biesaga M., Pyrzynska K., Trojanowicz M. (2000). Porphyrins in analytical chemistry. A review. Talanta. 51, p. 209-224. [7] Tabata M., Nishimoto J., Ogata A., Kusano T., Nahar N. (1996). Metalation of WaterSoluble Octabromoporphyrin with Lithium(I), Cadmium(II), and Mercury(II). Bull. Chem. Soc. Jpn. 69, p. 673-677. [8] D’Souza F., Hsieh Y.-Y., Deviprasad G.R. (1997). Electrocatalytic reduction of molecular oxygen using non-planar cobalt tetrakis-(4-sulfonatophenyl)-β-octabromoporphyrin. J. Electroanal. Chem. 426, p. 17-21. [9] Tabata M., Nishimoto J., Kusano T. (1998). Spectrophotometric determination of lithium ion using a water-soluble octabromoporphyrin in aqueous solution. Talanta. 46, p. 703-709. [10] Sun H., Tabata M. (1999). Separation and transport of lithium of 10-5M in the presence of sodium chloride higher than 0.1 M by 2,3,7,8,12,13,17,18-octabromo-5,10,15,20tetrakis(4-sulfonatophenyl)porphyrin. Talanta. 49, p. 603–610. [11] Rezaei B., Ghiaci M., Sedaghat M. E. (2008). A selective modified bentonite–porphyrin carbon paste electrode for determination of Mn(II) by using anodic stripping voltammetry. Sensors and Actuators B, 131, p. 439–447. [12] Jain A. K., Gupta V. K., Singh L. P., Khurana U. (1997). Macrocycle-based membrane sensors for the determination of cobalt(II) ions. Analyst, 122(6), p. 583-586. [13] Gupta V.K., Jain A.K., Singh L.P., Khurana U. (1997). Porphyrins as carrier in PVC membrane potentiometric sensors for nickel (II). Anal. Chim. Acta. 355, p. 33-41. [14] Vlascici D., Spiridon-Bizerea O., Făgădar-Cosma E. (2005). Comparison between the potentiometric answers of two Ni selective electrodes based on different porphyrin derivatives. Proceedings of The 12th Symposium on Analytical and Environmental Problems. Szeged, Hungary, Ed. Hungarian Academy of Sciences-SZAB, Szeged p. 30-34. [15] Gupta V. K., Jain A. K., Ishtaiwi Z., Lang H., Maheshwari G. (2007). Ni2+ selective sensors based on meso-tetrakis-{4-[tris-(4-allyl dimethylsilyl-phenyl)-silyl]-phenyl} porphyrin and (sal)2trien in poly(vinyl chloride) matrix. Talanta. 73, p. 803-811. [16] Dudas Z., Enache C., Fagadar-Cosma G., Armeanu I., Fagadar-Cosma E. (2010). Hybrid silica-porphyrin materials with tailored pore sizes. Materials Research Bulletin. 45, p. 11501156 [17] Buntem R., Intasiri A., Lueangchaichaweng W. (2010). Facile synthesis of silica monolith doped with meso-tetra(p-carboxyphenyl) porphyrin as a novel metal ion sensor. Journal of Colloid and Interface Science. 347, p. 8-14.

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ELECTROCHEMICAL ANALYSIS OF SOLID POLYMER ELECTROLYTE MEMBRANES USED IN LITHIUM-BASED BATTERIES. A literature survey. Gheorghe Fagadar-Cosma1*, Nicoleta Plesu2, Eugenia Fagadar-Cosma2, Gheorghe Ilia2, Smaranda Iliescu2, Lavinia Macarie2, Adriana Popa2 1

"Politehnica" University of Timisoara, Faculty of Industrial Chemistry and Environmental Engineering, Pta Victoriei 2, 300006-Timisoara, Romania, e-mail: gfagadar@yahoo.com 2 Institute of Chemistry Timisoara of Romanian Academy, 24 M. Viteazul Ave, 300223Timisoara, Romania

Polymer electrolyte membranes used in lithium batteries must possess some mechanical, chemical and electrical properties. The electrochemical characterization of such polymer membranes implies mainly the determination of the membrane ionic conductivity, the lithium transference number, and the electrochemical stability. 1. Membrane conductivity In order to be used as battery membrane, the polymeric material must be an electrical conducting separator. The conductivity is given not by the electron mobility but by the moving of the ions. Direct current measurements are therefore not applicable for measuring the electrical resistance and accordingly the ionic conductivity of the membrane. That is why the conductivity of the membrane is determined using alternating current, where no interface polarizations are occurring. Because of the periodic change of the electric field vector, the charge carrier accumulation is not produced and the current does not decrease with time. It is the case of impedance spectroscopy by applying a sinusoidal excitation voltage signal with low amplitude on the investigated sample. The answering signal is measured and the complex impedance is calculated over a wide frequency rage, usually from 1 Hz to 1 MHz. Two types of results plots are used for data analysis and the determination of the membrane resistance: Nyquist plots and Bode diagrams. The membrane ionic conductivity can be calculated by the formula: σ = (1/R)(L/A), where: R – the membrane resistance, L – the height of the sample between the electrodes, A – the cross-sectional contact area of the measured sample with the electrodes. For experimental determination the polymeric membrane is fixed between the metal electrodes (stainless steel, gold, platinum, etc.). Swagelok cells are very suitable in this case. The described method was applied for determination of polymer electrolyte ionic conductivities. This property of the membrane is crucial for its use in electrochemical cells, and especially in batteries. The target goal for battery membranes is 10-3 S/cm at room temperature. Some examples using this method are given in Table 1. The ionic conductivities of the polymer electrolytes depend strongly on the composition and temperature. It can change between 10-2 – 10-8 S/cm [12].

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Table 1. Membrane Siloxane lithium ion conducting polymer electrolytes (poly{[3-[2,3(carbonyldioxy)propoxy]propyl] methylsiloxane) Lewis-acid modified polymer LiBF4/ ethylene carbonate + diethyl carbonate + triethylphosphate Poly (vinylidene fluoride-co-hexafluoropropylene)-based composite polymer electrolyte P, O polymers (obtained from polyethylene glycols and organophosphates) containing lithium salts Polyphosphonates with lithium perfluoromethyl sulfonimide as the ionic salt Poly(ethylene imine) and lithium salts (LiF, LiCI, LiBr, Lil, LiSCN, LiClO4 and LiBF4) Lithium-salt/poly(ethylene oxide)complex polymer electrolytes (LiCF3SO3-PEOx and LiCIO4-PEOx) Cross-linked polysiloxanes containing oligoethylene oxide units, (OCH2CH2)n, as internal free chains complexed with LiN(CF3SO2)2 salt Ternary blends of poly(ethylene oxide), poly(bisphenol A-co-epichlorohydrin) and poly(vinyl ethyl ether), containing lithium perchlorate (LiClO4) Poly(oligo [oxyethylene] oxyterephthaloyl) and LiClO4 penetrated into microporous polyethylene Solid polymer electrolyte membranes prepared by photopolymerisation of poly(ethyleglycol)methacrylic oligomers in the presence of a lithium salt

Conductivity (S/cm) 10-7-10-3 (7.99x10-3 at 25oC and 3.69x10-2 at 60oC) 4-6 x10-3 (the best values) 10-3–10-2

Ref. 1 2 3

1-4 x10-3

4

0.6–1.0x10−3 at 22oC

5

10-8 (room temp.) 10-3 (150 °C) 10-3

6

2.50x10-5 to 1.62x10-4

8

10-4 - 10-3 S/cm (max 4.23x10-3) (25oC) 3.2×10−4 (25oC) higher than 10-4 (60oC)

9

7

10 11

2. Transference number Transference or transport number characterises the contribution of the charged particles present in the electrolyte to the charge transport across the electrochemical cell. It is a dimensionless parameter and it represents the fraction from the overall current transported by a particular charged species present in the electrolyte (ions and electrons). For the determination of the transference number the Bruce & Vincent method [13] can be used. All necessary equipment will be prepared in a glove box. The cell used is in a symmetrical Li/electrolyte/Li configuration (lithium metal electrodes in a Swagelok type), assembled in glove box due to highly reactivity of metallic lithium towards air constituents. The EIS spectrum is recorded in range of frequencies of 1Hz-100kHz. Potentiostatic polarization to the cell is applied (potential should be in range of 10-20mV vs. lithium) and the current evolution is followed until a steady state is reached (sometimes it can take even tens of hours). After the stabilization of the current, the polarization is stopped and another impedance spectrum (similarly as before) is recorded. The transference number is then calculated using the Bruce-Vincent formula: tLi = ISS(V-IoRo) / [I0(V-ISSRSS)], where: tLi – lithium transference number, V – applied potential, I0 – initial current, ISS – steady state current, R0 – initial resistance of the passivation layer, RSS – resistance of the passivation layer (steady state). Some examples are given in Table 2.

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Table 2. Membrane Poly (vinylidene fluoride-co-hexafluoropropylene)-based composite polymer electrolyte Composite polymer electrolyte based on poly(ethylene oxide)–lithium tetrafluoroborate (addition of sulphatepromoted superacid zirconia) Lewis-acid modified polymer (LiBF4/ ethylene carbonate + diethyl carbonate + triethylphosphate) Copolymer electrolyte: poly(laurylmethacrylate) and PEObased poly[oligo(oxyethylene)methacrylate] + polyethylene glycol dimethyl ether and doped with LiCF3SO3 Poly(acrylonitrile)-based gels (using lithium salts like LiN(CF3SO2)2 ) Poly(methyl methacrylate) as polimer matrix and different electrolytes

tLi+ 0.3-0.5

Ref. 3

0.42±0.05 (0.68±0.05 with S-ZrO2) ~0.6

14

0.5 (room temp.)

15

> 0.5 (enhanced to 0.7)

12

0.2-0.7

2

12, 16

3. The electrochemical stability window The electrochemical stability (decomposition voltage) of the polymer electrolyte membrane can be measured by linear sweep voltammetry. The working electrode is usually a stable metal electrode (platinum, stainless steel) or acetylene black, lithium metal being the counter and reference electrode. The potentials for anodic oxidation (anodic stability) for some membrane electrolytes, obtained by linear voltammetry, are presented in Table 3. The electrochemical stability windows are sufficiently wide for using the membranes in lithium batteries. The high values make them to resist for overcharge abuse in rechargeable Li-based batteries, which have a high working voltage by itself. Table 3. Membrane Anodic limit Poly (vinylidene fluoride-co-hexafluoropropylene)> 4.7 V vs Li/Li+ based composite polymer electrolyte Polymers containing ethylene oxide groups linked with 6 V vs Li/Li+ phosphate groups, LiClO4 Microporous polyethylene with highly conductive solvent- > 4.4 V vs Li/Li+ free polymer electrolyte based on poly(oligo [oxyethylene] oxyterephthaloyl) Solid polymer electrolyte membranes prepared by photo5 V vs Li/Li+ polymerisation of poly(ethyleglycol)methacrylic oligomers in the presence of a lithium salt Copolymerization of methylmethacrylate monomer onto 4.6 V vs Li/Li+ polyethylene separator Poly(lauryl methacrylate)-b-poly[oligo(oxyethylene) ~4 V vs Li/Li+ methacrylate]-based block copolymer electrolytes

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ACKNOWLEGEMENTS The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 266090 (SOMABAT). LIST OF REFERENCES [1] Spiegel E.F., Adamic K.J., Sammells A.F. (1998). Advanced High Energy Lithium Polymer Electrolyte Battery, DOD U.S. Army, Contract no. DAAB07-98-C-G005. [2] Lalia B.S., Yoshimoto N., Egashira M., Morita M. (2009). Effects of Lewis-acid polymer on the electrochemical properties of alkylphosphate-based non-flammable gel electrolyte. Journal of Power Sources, 194, p. 531–535. [3] Xie H., Tang Z., Li Z., He Y., Liu Y., Wang H. (2008). PVDF-HFP composite polymer electrolyte with excellent electrochemical properties for Li-ion batteries. J. Solid State Electrochem. 12, p. 1497–1502. [4] Morris R.S., Dixon B.G. (2003). A novel approach for development of improved polymer electrolytes for lithium batteries. Journal of Power Sources 119–121, p. 487–491. [5] Dixon B.G., Morris R.S., Dallek S. (2004). Non-flammable polyphosphonate electrolytes, Journal of Power Sources 138, p. 274–276. [6] Chiang C.K., Davis G.T., Harding C.A., Takahashi T. (1986). Polymeric electrolyte based on poly(ethylene imine) and lithium salts, Solid State Ionics 18-19, p. 300-305. [7] Weston J.E., Steele B.C.H. (1981). Thermal history-conductivity relationship in lithium salt-poly(ethylene oxide) complex polymer electrolytes, Solid State Ionics 2, p. 347-354. [8] Zhang Z.C., Jin J.J., Bautista F., Lyons L.J., Shariatzadeh N., Sherlock D., Amine K., West R. (2004). Ion conductive characteristics of cross-linked network polysiloxane-based solid polymer electrolytes, Solid State Ionics 170, p. 233–238. [9] Rocco A.M., de Assis Carias A., Pereira R.P. (2010). Polymer electrolytes based on a ternary miscible blend of poly(ethylene oxide), poly(bisphenol A-co-epichlorohydrin) and poly(vinyl ethyl ether), Polymer 51, p. 5151-5164. [10] Oh J.-S., Kang Y., Kima D.-W. (2006). Lithium polymer batteries using the highly porous membrane filled with solvent-free polymer electrolyte, Electrochimica Acta 52, p. 1567–1570. [11] Nair J.R., Gerbaldi C., Destro M., Bongiovanni R., Penazzi N. (2011). Methacrylic-based solid polymer electrolyte membranes for lithium-based batteries by a rapid UV-curing process, Reactive & Functional Polymers 71, p. 409–416. [12] Stephan A.M. (2006). Review on gel polymer electrolytes for lithium batteries, European Polymer Journal 42, p. 21–42. [13] Bruce P.G., Vincent C.A. (1987). Steady state current flow in solid binary electrolyte cells, J. Electroanal. Chem. 255, p. 1-17. [14] Croce F., Settimi L., Scrosati B. (2006). Superacid ZrO2-added, composite polymer electrolytes with improved transport properties, Electrochemistry Communications 8, p. 364– 368. [15] Soo P.P., Huang B., Jang Y.-I., Chiang Y.-M., Sadoway D.R., Mayes A.M. (1999). Rubbery Block Copolymer Electrolytes for Solid-State Rechargeable Lithium Batteries, Journal of The Electrochemical Society 146, p. 32-37. [16] Appetecchi G.B., Croce F., Scrosati B. (1995). Kinetics and stability of the lithium electrode in PMMA-based gel electrolytes, Electrochim. Acta 40, p. 991. [17] Gao K., Hu X., Yi T., Da C. (2006).PE-g-MMA polymer electrolyte membrane for lithium polymer battery, Electrochim. Acta 52, p. 443–449.

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MASS-SPECTROMETRY USED IN CHARACTERIZATION OF PIGMENTS Gheorghe Ilia, Cornelia Crasmareanu, Smaranda Iliescu, Lavinia Macarie, Nicoleta Plesu, Adriana Popa Institute of Chemistry Timisoara of Romanian Academy, 24 Mihai Viteazul Blv., RO-300223 – Timisoara, Roumania, email: gheilia@yahoo.com ABSTRACT Naphthol AS pigmens synthesised by RPTC were characterized by M2 mass spectrometry. The rezults show that this technique is not very a reliable method for characterization of such compounds. INTRODUCTION Synthetic organic pigments are carbon based molecules manufactured from petroleum compounds, acids, and other chemicals, usually under intense heat or pressure. The techniques for producing these substances on an industrial scale were invented after 1860, which created the modern era of consumer color. Chemical and industrial innovations increased at an astonishing pace through the end of the 19th century and have continued up to the present. Synthetic organic pigments are fabricated from a limited number of elements. The color creating aspects of the molecule depend on the chromophore, a pairing or grouping of atoms that create a complex and shifting cloud of electrons across the electron shells of two or more atoms. These electron transitions permit efficient absorption of specific light wavelengths, which creates a color that is the visual complement to the absorbed light (a compound absorbing in the "blue" and "violet" or short wavelengths appears to have a yellow color; a compound absorbing in the "green" wavelengths appears to have a purple color, etc.). Other groups of atoms called auxochromes influence the pigment color by altering the light absorbing capacity of the chromophores, usually in the long wavelengths.1 Naphthol. (Naphtol is a registered trademark of Hoechst AG; the generic label for the same compounds manufactured by other companies is naphthol, with a second h. The word is from the Greek for "mineral oil", and salutes the origin of these pigments in petroleum.) Developed and patented in 1911, the naphthol compounds represent the single largest group of azo dyes and pigments. (In fact, about 20% of all synthetic organics available, over 50 in the red category alone, are naphthol pigments).2 Originally used as cotton dyes, they were soon laked as pigments and were first used in artists' paints in the 1920's. The most important group for artists is the naphthol AS pigments. The color range is concentrated in the long wavelength end of the spectrum, including warm orange (PO24, PO38), scarlet (PO5, PR188, PR261), many reds (PR2, PR3, PR5, PR7, PR8, PR9, PR17, PR22, PR112, PR150, etc.), carmines (PR23, PR146, the many pigments listed under PR170), maroon violet (PV13, PV25, PV44), and brown (PBr1). 3

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In this paper we prezent the characterization of some Naphthol AS pigments by Mass Spectrometry MATERIALS and METHODS Spectra recording Mass spectra were obtained using a mass spectrometer Esquire 6000 ESI (electrospray ionization) from Bruker-Daltonics. The compound was diluted before measurements at 5 pmol/µl in acetonitrile containing 5% ammonia and was injected in electrospray chamber by direct infuzion, with a constant flow of 240 µl/h. The mass spectra were obtained in the positive mode. RESULTS AND DISSCUSION The pigments were obtained by RPTC technique when a mixture of benzenediazonium chloride in water, and 3-hydroxy-2-carboxylic acid anilides in nitrobenzene and perfluorooctyl potassium sulfonates (PFOS-K+) as catalyst, was vigorously stirred at room temperature (Figure 1 and Table 1).

Scheme 1. Structure of pigment, I, II and III Dye

X

Y

Z

I II III

H H H

NO2 NO2 NO2

H H H

Table 1. Analyzed pigments U V W H NO2 C2H5

OCH3 H H

H H H

Molecular formula C24N4O5H17 C23N5O6H14 C25N4O4H19

M 441 456 439

Various analytical methods of analysis have been successfully used for the study of synthetic organic pigments, structural characterization by microscopic techniques and X-ray diffraction, and chemical analysis and colour measurement by spectroscopic methods, such as VIS spectrophotometry, IR, NMR, and MS. The use of MS for the analysis of synthetic colorants has been surveyed by Van Bremen, with a particular emphasis on the benefits of various ionisation methods. In figures 2-4 are presented molecular peaks fragmentation of analized pigments.

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Intens.

+MS2(442.0), 12.1-12.3min #(135-137)

10

424.8

8

6

4 345.9

2 337.7 200.7 0 50

100

150

200

250

300

350

400

450

m/z

2

Fig. 2. Fragmentation of molecular peak of pigment P I (MS ) Mass spectra were obtained in the positive mode. In figure 2 it is shown the positive ion mass spectrum of pigment I. By eliminating the positive ions can be identified only one peack m/z=426.0 [M-O]. Intens.

+MS2(457.0), 16.3-18.3min #(378-409) 377.1

60

40

20

361.7 351.5 310.6 389.4

271.8

439.5 0 50

100

150

200

250

300

350

400

450

m/z

Fig. 3. Fragmentation of molecular peak of pigment P II (MS2)

In figure 3 is presented MS2 spectrum of compound II. The next fragmetations could be idetntified as: m/z=439.5 [M-O]; m/z=410.0 [M-NO2].

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+MS2(440.0), 12.1-14.2min #(280-310) 253.6

2.0

1.5

315.7

377.2

1.0

165.8

290.3 210.6

0.5

396.6

421.4

0.0 50

100

150

200

250

300

350

400

450

m/z

Fig. 4. Fragmentation of molecular peak of pigment P III (MS2) For pigment PIII next fragmentations can be identified: m/z=421.4[M-OH]: m/z=396.6[MCONH], m/z=315.7[M-C6H4NO2]; m/z=290.3[M-N=N-C6H4NO2] CONCLUSION Mass spectrometry applied to characterization of Naphtol AS pigments is not a very reliable method when positive mode is used for MS2 spectra REFERENCES 1. http://www.handprint.com/HP/WCL/pigmt1d.html 2. W. Herbst, K. Hunger, G. Wilker, H. Ohleier, R. Winter, Industrial organic pigments: production, properties, applications, 3rd edition, Wiley-VCH, Weinheim, 2004. 3. Colour Index (C.I.) http://www.colour-index.org/ 4. Peters, A. T., Freeman, H. S. (Ed.): Advances in Color Chemistry Series 2: Analytical Chemistry of Synthetic Colorants, Volume 2, Chapman and Hall, London, 1995, pp. 96-116.

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REMOVAL OF ESCHERICHIA COLI FROM WATER BY SYSTEM BASED ON PHOSPHORUS - CONTAINING SYNTHETIC PREFORMED POLYMER Adriana Popa1, Ileana Nichita2, Smaranda Iliescu1, Gheorghe Ilia1, Monica Butnariu2 1

Institute of Chemistry Timisoara of Romanian Academy, 24 Mihai Viteazul Blv., 300223 Timisoara, Romania 2 „Banat” University of Agricultural Science and Veterinary Medicine, 119 Calea Aradului, Timisoara, Romania

ABSTRACT A study of the removal of Escherichia Coli cells from water by α-hydroxyphosphonic group grafted on styrene-6.7% divinylbenzene copolymer was made. The α-hydroxyphosphonic containing synthetic preformed polymer is well suited for subsequent use of the product as antibacterial agent. INTRODUCTION Contamination by microorganisms is of great concern in a variety of areas, such as medical devices, healthcare products, water purification systems, hospitals, dental office equipment, food packaging, food storage, household sanitation, etc.[1, 2] There is a definite need for new materials with antimicrobial activities. An area of polymer research that presents great current interest, yet has received insufficient attention, is that of the development of polymers with antimicrobial activities, generally known as polymeric biocides. The problem of the preparation of polymeric biocides can be solved in many cases, if the bactericide is covalently grafted on polymeric carriers or other insoluble support materials [3-5]. Since the early 90’s α-hydroxyphosphonates have attracted much attention due to their wide ranging biological activity [6-8] and their usefulness as synthetic intermediates for other biologically important α-substituted phosphoryl compounds. This study is concerned with the removal of E. coli cells from water by polymeric biocide derived from the polymer-analogous reaction between phosphorous acid and aldehyde grafted on styrene -6.7% divinylbenzene copolymer. MATERIALS and METHODS 1. Phosphorus - containing synthetic preformed polymer The obtaining of the α-hydroxyphosphonic acids by reaction between phosphorous acid and aldehyde grafted on styrene -6.7% divinylbenzene copolymer (Scheme 1) was confirmed by IR spectrum, the group P =O was identified. P

HOP(OH)2 + K3PO4

CH2O

THF

P

CH2O CH-P(O)(OH)2

CHO

OH

Scheme 1. Obtaining of α-hydroxyphosphonic acid on synthetic preformed polymer.

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2. Antibacterial activity study of the polymer-grafted α-hydroxyphosphonic group against Escherichia coli The antibacterial activity of the polymer-grafted α-hydroxyphosphonic group against Escherichia colis was studied in batch system. In an Erlenmayer flask fitted with magnetical stirring were introduced 0.6 g of polymeric disinfectant, 29 mL of sterilized water and the mixture was stirred at room temperature for 1 hour. 1 mL culture of E. coli (contained 107 cells/mL) was then added in the mixture containing the polymeric disinfectant, at room temperature and stirring was continued. At a precisely interval samples of 1 mL were collected and the number of colony forming units (C.F.U) was determined by the decimal serial dilutions method. From each diluted solution two Petri plates were seeded with 1 mL of solution, then 10 mL of nutrient gelose melted and cooled at 45 oC was added and after homogenisation by stirring, the mixture was left to solidify at room temperature. The obtained plates were incubated for 24 hours at 37 oC. The number of colonies/mL was determined as an average value for the two plates by standard procedures [9]. RESULTS In Figure 1, is presented the process of decrease of the log (CFU) as a function of the exposure time.

log(CFU)

8 7 6 5 4 3 0

3

6

9

12

15

18

21

time, h Fig.1. Plot of log(CFU) versus the exposure time using polymer-supported αhydroxyphosphonic group against E. coli. In order to compare quantitatively the ability to decrease the viable cell number, the following was considered. In the early stage of contact, a linear relation was observed between the logarithm of viable cell number and contact time until 3h. This process could eventually be interpreted as “adsorption-like” phenomena. Initially, the process is very rapid in the first three hours, as all the active centers are available. Then a saturation process could occur, which could explain the evolution of log(CFU) depend as a function of the exposure time, evolution very similar to a monomolecular layer adsorption isotherm.

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Linear correlations were observed until about 3 h from the start. Thus the removal coefficient of viable cell number (R) Kao et al.’s [10], Isquith and McCollum’s and Kawabata et al.’s [11] was defined as equation (1) and calculated:

CR =

N V ⋅ log 0 W ⋅t Nt

(ml / g.h)

(1)

where: V is the volume (mL) of viable cell suspension, W- the dry weight (g) of the polymer, t- the contact time (h), N0 the initial viable cell number and Nt the viable cell number (cells/mL) at contact time t. Table 1 lists removal coefficient value of viable cell numbers from water by αhydroxyphosphonic group grafted on copolymer. Table 1. Removal coefficient CRa of viable cell numbers of E.coli from water at contact with the polymer. b Prod. N0 (cells/mL) Ntc (cells/mL) CR (mL/g.h) St-6.7%DVBHOPHOS 13.5.106 0.49.105 40.66 a. Determined at 37oC by the contact of the insoluble polymer (0.6 gram) with 30 mL of viable E. coli cell suspension. b. N0 – the initial viable cell number. c. Nt –the viable cell number at contact time (t = 3 hours).

R, %

The antibacterial activity of was evaluated through the percentage of reduction of the colony units. The percentage of reduction of the colony units (R, %) was determined from the decimal logarithm of the colony forming units number (CFU). According to literature date [12] a species is considered as having bactericide action if 99.9% of the bacteria cells are destroyed in 18 hours. As after 18 hours of exposure, around half of the bacterial cells were destroyed; we can characterize the product as bacteriostatic (R = 43.90 %). The resulted is presented in Figure 2. 45 40 35 30 25 20 15 10 5 0 0

3

6

9

12

15

18

21

time, h

Fig. 2. Percentage of reduction of the surviving cells versus the exposure time using polymersupported α-hydroxyphosphonic against Escherichia coli.

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CONCLUSIONS

The removal of E. coli cells from water by α-hydroxyphosphonic group grafted on styrene6.7% divinylbenzene copolymer was made. Removal coefficient value of viable cell numbers from water is 40.66 mL/g.h. As after 18 hours of exposure, around half of the bacterial cells were destroyed; the product is bacteriostatic (R = 43.90 %).

LIST OF REFERENCES

[1] Patel M. B., Patel S. A., Ray A., Patel R. M. (2003). Synthesis, Characterization, and Antimicrobial Activity of Acrylic Copolymers, J. Appl. Polym. Sci., 89, p. 895-900. [2] Park E.-S., Lee H.-J., Park H.-Y. et all, (2001). Antifungal effect of carbendazim supported on poly(ethylene-co-vinyl alcohol) and epoxy resin, J. Appl. Polym. Sci., 80, p. 728-736. [3] Ikeda T., Hirayama H., Yamaguchi H., et all, (1986). Polycationic Biocides with Pendant Active Groups: Molecular Weight Dependence of Antibacterial Activity, Antimicrob. Agents Chemother., 30, p. 132-140. [4] Ikeda T., Yamaguchi H. Tazuke S., (1990). Molecular Weight Dependence of Antibacterial Activity in Cationic Disinfectants, J. Bioact. Compat. Polym., 5, p. 31-42. [5] Tashiro T., (1993). Removal of Escherichia coli from water by systems based on insoluble polystyrene–poly(ethylene glycol)s, –polyethylenimines, and –polyethylenepolyamines quaternized, Journal of Applied Polymer Science, 43, p. 1369-1377. [6] Stowasser B., Budt K.-H., Jian-Qi L., et all, (1992). New hybrid transition state analog inhibitors of HIV protease with peripheric C2-symmetry, Tetrahedron Lett., 33(44), p. 66256628. [7] Maier L., (1993). A novel synthesis of bis-(α-hydroxyalkyl)phosphinic acids, Phosphors, Sulfur and Silicon, 76, p. 119-122. [8] Rath N.P, Spilling C.D, (1994). The enantioselective addition of dialkylphosphites to aldehydes: Catalysis by a lanthanum binaphthoxide complex, Tetrahedron Lett., 35(2), p. 227-230. [9] Raducanescu H., Bica-Popii V., (1986). Bacteriologie Veterinara, Ed. Ceres, Bucuresti. [10] Kao I.C., Robker D.E., Fan L.T., et all, (1972), Analysis and properties of a quaternary ammonium triiodide ion exchange sterilization process, J. Ferment. Technol., 50, p. 438-445. [11] Kawabata N., Hayashi T., Matsumoto T., (1983). Removal of Bacteria from Water by Adhesion to Cross-Linked Poly(Vinylpyridinium Halide), Appl. Environ. Microbiol., 46, p.203-210. [12] Daniels S. L., Adsorptio of Microorganism to Surfaces, G. Gitton and K.C. Marshall. (Eds), John Wiley, New York, (1980), 2-58.

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IN VITRO MUTAGENICITY EVALUATION OF IRON OXIDE NANOPARTICLES BY THE BACTERIAL REVERSE MUTATION ASSAY Brigitta Szalay1,2, Tünde Vezér2 1

National Institute of Environmental Health, Department of Toxicology, H-1097 Budapest, Gyáli út 2-6, Hungary; e-mail: szalay.brigitta@oki.antsz.hu 2 Department of Public Health, University of Szeged, H-6720 Szeged, Dóm tér 10, Hungary ABSTRACT Iron oxide nanoparticles are becoming highly promising tools for a wide spectrum of biomedical applications. The aim of our work was to determine the potential mutagenic effects of Fe2O3 and Fe3O4 nanoparticles (NPs), using bacterial reverse mutation assay. This is still the most widely used method for evaluating chemicals and environmental samples for mutagenic activity. In the bacterial reverse mutation assay, two genotypic variants of the Salmonella typhimurium strains (TA98 and TA1535) were used. Fe2O3 and Fe3O4 NPs were incubated with these two strains in four different doses both in presence and in absence of the rat liver metabolic activation system (S9); concurrently, appropriate positive controls were used to validate the test. The assessment of the results was based on the number of reverse mutants. The average number of reverse mutants per plate treated with NPs was less than double compared to negative control. Fe2O3 and Fe3O4 NPs proved to have no mutagenic effect in the bacterial cellular systems tested, in that they did not significantly increase the number of revertant colonies. Our findings indicate that Fe2O3 and Fe3O4 NPs are non mutagenic in bacterial reverse mutation assay under the present test conditions. These results are useful to expand our knowledge on the safety of iron oxides NPs. INTRODUCTION A variety of metal oxides have been developed as nanoparticles (NPs). Investigation of these NPs is currently a very interesting area of scientific research, due to a wide range of potential applications in cosmetics, electronics and medical diagnostics. A complete list of the potential applications of nanotechnology is too diverse to discuss in detail, but without doubt, one of the greatest values of this technology will be in the development of new and effective medical treatments (Sahoo et al., 2007). Iron oxide NPs have a high potential for use in several biomedical applications – including for example magnetic detection, hyperthermia and magnetic resonance imaging (Sun et al., 2007, Balasubramanyam et al, 2010) – and there have been a few studies related to toxicity examination of nanoparticulate iron oxides. There are several methods to study the safety of nanomaterials. The bacterial reverse mutation assay is a simple biological test to evaluate the mutagenic potential chemicals and environmental materials (Ames et al., 1975). The aim of this study was to define mutagenic activity of Fe2O3 and Fe3O4 NPs using in vitro bacterial reverse mutation assay. MATERIALS AND METHODS Fe2O3 and Fe3O4 nanoparticles, and dimethylsulphoxide (DMSO) (purity > 99.5%) were obtained from Sigma–Aldrich Co. (St Louis MO, USA). The characteristics of nanoparticles declared by the manufacturer were as follows: Fe2O3 nanopowder, 29nm average particle size (TEM), BET surface area > 40m2/g; Fe3O4 nanopowder, spherical, < 50nm particle size (TEM), BET surface area > 60m2/g. The mutagens 2-aminoanthracene (2AA) (purity 96%),

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sodium azide (SAZ) (purity > 99.5%), and 4-nitro-1,2-fenilendiamin (NPDA) (purity 98%) were likewise obtained from Sigma–Aldrich Co. Salmonella typhimurium tester strains TA98 and TA1535 were supplied by Xenometrix AG (Allschwil, Switzerland). In this study, different concentrations (16, 63, 500, 1000 μg/plate) of Fe2O3 and Fe3O4 nanoparticles suspended and ultrasonicated in DMSO (50 μl) were added to an overnight culture (100 μl) and 10/20% of S9 mixture or sodium phosphate buffer (0.1 mM) (500 μl). The mixture was pre-incubated under shaking at 37○C for 30 or 60 minutes, then it was added to top agar (2 ml) containing 10% of histidine/ biotin (0.5 mM) for the tester strains, and was finally poured onto a minimal agar plate. After incubation at 37○C for 48 h, the plates were examined for the number of His+/wild revertant colonies. Viable cells were scored and the bacterial background lawn was observed by light microscopy (Maron and Ames, 1983). In each experiment DMSO was used as a negative control (NC=0) and various diagnostic mutagens: SAZ (1 μg/plate) for TA1535 without S9 mixture, NPDA (4 μg/plate) for TA98 without S9 mixture as well as 2AA (1-2 μg/plate) for both tester strains with S9 mixture were included as positive controls (PC). A positive response in the test is defined as at least twofold increase in histidine-independent revertant colonies compared to the negative control in both strains (Ames et al., 1975). Each concentration was tested for toxicity and mutagenicity on six plates. The data were represented as mean±standard deviation (SD). RESULTS Within the tested concentration range (16, 63, 500 and 1000 μg/plate) neither Fe2O3 nor Fe3O4 NPs showed to induce any toxic effect, i.e. reduction in the number of revertant colonies and change in the auxotrophic background lawn in tester strains. The positive controls (SAZ, NPDA and 2AA) increased the number of revertant colonies, at least four times vs. vehicle, showing the capability of the system to detect a mutagenic effect.

Number of revertant colonies [log]

10000

Fe3O4 TA98 -S9 Fe3O4 TA98 +10%S9

1000

Fe3O4 TA98 +20%S9

100

Fe2O3 TA98 -S9

10

Fe2O3 TA98 +10%S9

1 0

16

63 500 Dose (μg/plate)

1000

PC

Fe2O3 TA98 +20%S9

Figure 1 Mutagenic activity of Fe3O4 and Fe2O3 NPs in S.Typhimurium TA98 in presence and in abscence of S9 (Mean+SD). PC: positive controls are follows SAZ (1 μg/plate), NPDA (4 μg/plate) and 2AA (1-2 μg/plate).

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The average number of reverse mutants was similar in the groups treated with Fe2O3 and Fe3O4 NPs and in the negative control. None of the revertant rates was greater than or equal to the twofold of the negative controls, and no concentration-dependent increase was observed (Figure 1 and 2).

Number of revertant colonies [log]

1000

Fe3O4 TA1535 -S9 Fe3O4 TA1535 +10%S9

100

Fe3O4 TA1535 +20%S9 Fe2O3 TA1535 -S9

10

Fe2O3 TA1535 +10%S9 Fe2O3 TA1535 +20%S9

1 0

16

63

500

1000

PC

Dose (μg/plate)

Figure 2 Mutagenic activity of Fe3O4 and Fe2O3 NPs in S. typhimurium TA1535 in presence and in abscence of S9 (Mean+SD). PC: positive controls or diagnostic mutagens are follows SAZ (1 μg/plate), NPDA (4 μg/plate) and 2AA (1-2 μg/plate). The results were identical in absence and in presence of the rat liver metabolic activation system (S9). In the negative control group of each tester strain, the average number of reverse mutants was within the range of the historical control data of our laboratory, and the positive controls showed significant mutagenicity. These results demonstrated that Fe2O3 and Fe3O4 NPs are not mutagenic to the bacterial strains TA98 and TA1535. CONCLUSION The bacterial reverse mutation assay was conducted with Fe2O3 and Fe3O4 nanoparticles. Our results indicated that iron oxide nanoparticles were not toxic and not mutagenic on bacterial cells of the TA98 and TA1535 Salmonella typhimurium strains. Moreover, mutagenic activity of Fe2O3 and Fe3O4 NPs did not appear even in the presence of a cytochrome P450-based metabolic activation system (S9 mixture). This implication is in accord with literature data on the mutagenic potential of metal oxide NPs. The mutagenic activity of Al2O3, Co3O4, TiO2, and ZnO NPs to S. typhimurium TA97a and TA100 was found to be negative in the absence and presence of S9 mixture (Pan et al., 2010). On the contrary, iron-platinum (FePt) NMs tested in the Ames test (using Salmonella TA98, TA100, TA1535, TA1537 and E. coli WPA2uvrA strains) with and without S9 mixture were mildly positive in the TA100 strain without S9 mixture (Maenosono et al., 2007). Iron oxide nanoparticles are an important group of nanomaterials with extensive potential of biomedical applications, e. g. as contrast agents in magnetic resonance imaging. Because of

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such biomedical applications of iron oxide NPs, more detailed toxicological investigations are necessary to determine their potential toxic and genotoxic effects. LIST OF REFERENCES Ames B. N., McCann J., Yamasaki E. (1975). Methods for detecting carcinogens and mutagens with the Salmonella/mammalian-microsome mutagenicity test. Mutation Research 31, p. 347–364. Balasubramanyam A., Sailaja N., Mahboob M., Rahman M. F., Hussain S. M, Grover P. (2010). In vitro mutagenicity assessment of aluminium oxide nanomaterials using the Salmonella/microsome assay. Toxicology in Vitro 24, p. 1871–1878. Maenosono S., Suzuki T., Saita S. (2007). Mutagenicity of water-soluble FePt nanoparticles in Ames test. J Toxicol Sci 32, p. 575–579. Maron D. M, Ames B. N. (1983). Revised methods for the salmonella mutagenicity test. Mutation Research 113, p. 173-215. Pan X., Redding J. E, Wiley P. A., Wena L., McConnell J. S., Zhang B. (2010). Mutagenicity evaluation of metal oxide nanoparticles by the bacterial reverse mutation assay. Chemosphere 79, p. 113–116. Sahoo S. K., Parveen S., Panda J. J. (2007). The present and future of nanotechnology in human health care. Nanomedicine: Nanotechnology, Biology and Medicine 3, p. 20-31. Sun J., Zhou S., Hou P., Yang Y., Weng J., Li X., Li J. (2007). Synthesis and characterization of biocompatible Fe3O4 nanoparticles. Biomed. Mater. Res. A 80, p. 333–341.

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ADSORPTION OF PHENOLIC COMPOUNDS FROM WATER ON POLYMERIC ADSORBENTS WITH OLEFIN GROUPS Radu Ardelean1, Corneliu-Mircea Davidescu1, Adriana Popa2, Gheorghe Ilia2, Smaranda Iliescu2, Lavinia Macarie2 1

”Politehnica” University, Faculty of Industrial Chemistry and Enviromental Engineering, Physical Chemistry Department, Bul. V. Parvan 6, 300223 Timisoara, Roumania 2 Institute of Chemistry Timisoara of Romanian Academy, 24 Mihai Viteazul Blv., RO300223 – Timisoara, Roumania

ABSTRACT Removal and recovery of aromatic pollutants from water by solid adsorbents have been of considerable concern recently. In this paper, adsorption of phenolic compounds from aqueous solution onto a polymeric adsorbent with olefin groups at temperatures from 297 K was studied. INTRODUCTION Water pollution, especially the industrial wastewater containing aromatic compounds, is one of the most urgent environmental problems. Phenolic compounds are pollutants of great concern because of the high toxicity and possible accumulation in the environment. Most of these compounds are recognized as organic contaminants in environmental systems [1, 2]. For phenolic compounds adsorption on a specific polymeric adsorbent, the solute–adsorbent interaction will play an important role in the adsorption capacity from aqueous solution [3]. In this preliminary study, a polymeric adsorbent P1n was prepared from benzaldehyde poly(styrene-co-divinylbenzene), and it was tested in batch experiments for phenol, 2,6dimethylphenol and 2,4,6-trimethylphenol in aqueous solution. EXPERIMENTAL PART Synthesis of resin with benzaldehyde groups The synthesis of the S-DVB copolymers functionalized with benzaldehyde groups were performed by the method previously described (Schema 1) [4]. 5 g sample of chloromethylated copolymer, sodium hydrogen carbonate (molar ratio – chloromethyl groups (CH2Cl): NaHCO3 = 1:2) and 100 ml dimethyl-sulfoxide were added to a 250 ml round bottom flask fitted with a reflux condenser, mechanical stirrer and thermometer. The mixture was maintained under stirring for 24 h at 130 oC. After cooling, the polymer were separated by filtration, washed with DMSO, hot distilled water, methanol, acetone and finally with diethyl ether and dried at 50 oC for 24 hours.

P

CH2Cl

DMSO/NaHCO3 24 h, 130 oC

P

CHO

Scheme 1. Obtaining of resin with benzaldehyde groups

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General procedure for Wittig reactions in phase transfer catalysis conditions The synthesis of the S-6.7%DVB copolymers functionalized with olefin groups was performed by the method previously described [4]. A mixture of benzaldehyde (4.31 mmoles/g) grafted on styrene-divinylbenzene copolymer (1 g), tetraethylammonium iodide (0.05 g), solvent (THF/CH3OH=1:1) (20 ml), K2CO3 (0.55 g) and a metyltriphenylphosphonium bromide were stirred 20 hours at 60 oC. The molar ratio benzaldehyde grafted on styrene-divinylbenzene copolymer : phosphonate was 1:2. The final product was separated by filtration, washed with ethanol, methylenchloride, diethyl ether and then dried at 50 oC for 24 hours. Determination of the adsorbtion capacity for P1n adsorbent Batch adsorption experiments were carried out by allowing an accurately weighted amount of P1n adsorbent to reach equilibrium with phenolic compounds solution of an initial concentration of 0,300 mmoles/L at a temperature of 297 K. About 0.200 g of dry adsorbent was weighted and added into 100 mL of phenolic compounds aqueous solution, using a 200 mL Erlenmeyer flask. The mixture was continuously stirred for 24 hours, using a magnetic stirrer, to reach the adsorbtion eqiulibrium. An amount of 1 mL solution was sampled from the flasks at various time intervals to determine adsorption kinetics. After 24 hours, the mixtures were vacuum-filtered in order to determine phenolic compounds concentration at equilibrium. The residual concentration of phenolic compounds was determined by UV spectrophotometry, measuring the absorbtion of phenol solutions at a wavelength of 270 nm, 2,6-dimethylphenol solutions at a wavelength of 269 nm and 2,4,6-trimethylphenol solutions at a wavelength of 270 nm. For UV measurements we used a UV-VIS Shimadzu UVmini 1240 spectrophotometer. RESULTS Wittig reaction on polymer support is presented in scheme 2:

CHO

P

CH=CH2

P

P1n PTC

Ph3RP+ Br-

Ph3P=O

Scheme 2. Chemical modification of benzaldehyde grafted on polymer through Wittig polymer-analogous reactions in PTC conditions The concentration of phenol in aqueous solution was analyzed by UV analysis performed on a Shimadzu UV-VIS spectrophotometer with the wavelength at 270 nm. The UV absorbtion spectra of the phenol in aqueous solution is presented in figure 1:

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Absorbtion

The 17th Int. Symp.on Analytical and Environmental Problems, Szeged, 19 September 2011

0,6

0,4

0,2

0,0 220

240

260

280

300

320

340

360

wavelength, nm

Figure 1. – UV absorbtion spectra of phenol in aqueous solution Comparative phenolic compounds adsorbtion from aqueous solution for P1n adsorbent from 0 to 24 hours is presented in figures 2 and 3.

Figure 2. Comparative phenolic compounds adsorbtion from aqueous solution for P1n adsorbent. Preliminary experiments showed that the adsorption of phenolic compounds is fast at the initial stages and becomes slower near the equilibrium.

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Figure 3. Comparative phenolic compounds adsorbtion from aqueous solution for P1n adsorbent. The 2,6-dimethylphenol adsorption capacity on the functionalized polymer P1n is greater than the adsorption capacity of 2,4,6-trimethylphenol. The amount of phenol adsorbed on the polymer P1n is much less than the amount of 2,6-dimethyl phenol and respectively 2,4,6trimethyl phenol adsorbed on P1n. CONCLUSIONS The preliminary experiments showed that the adsorption of phenolic compounds is fast at the initial stages and becomes slower near the equilibrium. The rate of phenolic compounds removal from water is very rapid during the initial 30 min and decreases thereafter. Acknowledgements The authors are grateful for functionalized polymers that were obtained by partial financial support from Program no. 2, Project no. 2.4 from Romanian Academy, Institute of Chemistry Timisoara of Romanian Academy.

LIST OF REFERENCES [1] Ku Y., Lee K.C. (2000). Removal of phenols from aqueous solution by XAD-4 resin. J. Hazard. Mater. B80, p. 59–68. [2] Aksu Z., Yener J. (2001). A comparative adsorption/biosorption study of monochlorinated phenols onto various sorbents. Waste Manage. 21, p. 695–702. [3] Ardelean R., Davidescu C.M., Popa A. (2010). Adsorption of p-Nitrophenol from Water on Polymeric Adsorbents. Chem. Bull. "POLITEHNICA" Univ. (Timisoara), 55(69), p.131135. [4] Popa A., Ilia G., Davidescu C.M., Iliescu S., Macarie L., Maranescu B. (2006). Reactii Wittig ale sarurilor de fosfoniu cu liganzi macromoleculari functionalizati cu grupari aldehidice, Materiale Plastice 43(1), p. 62-64.

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USE OF IMPREGNATED RESINS AS ADSORBENTS IN VIEW OF HEAVY METALS REMOVAL FROM AQUEOUS SOLUTIONS Mihaela Ciopec1*, Zoltán Galbács2, Corneliu Mircea Davidescu1, Gabor Galbács2, Adina Negrea1, Adriana Popa3, Petru Negrea1 1

University „Politehnica” Timisoara, Faculty of Industrial Chemistry and Environmental Engineering, Piata Victoriei, no. 2, Timisoara, 300006, ROMANIA * e-mail: mihaela.ciopec@chim.upt.ro 2 University of Szeged, Departament of Inorganic and Analytical Chemistry, H-6701 Szeged, P.O.B. 440, Hungary 3 Romanian Academy, Institute of Chemistry Timisoara of Romanian Academy, Mihai Viteazul Blv., no. 24, Timisoara, 300223, ROMANIA ABSTRACT The presence of heavy metal ions in environment is a major concern because of their toxicity to many life forms. Heavy metal ions can be removal from water by adsorption on solid support. In the present work, we tested the adsorption of metal ions on solvent impregnated resin (SIR). Di-(2-ethylhexyl)-phosphoric acid (D2EHPA) has been chosen as an extractant for the purpose of this study. The interaction between XAD4 resin and D2EHPA was evaluated by physico-chemical methods of analysis (EDX and SEM). The experimental studies on adsorption of metal ions were carried out on Pb2+, Cu2+, Cd2+, Cr3+, Ni2+, Fe3+, Zn2+ and Ca2+. A separation method was developed for metals ions and was investigated the influence of contact time on the residual concentration of metal ions, on their removal efficiency and on the adsorption capacity of resin towards metal ions. Keywords: Amberlite XAD4; D2EHPA; Solvent impregnated resin (SIR); Heavy Metals Removal INTRODUCTION Heavy metal pollution of industrial wastewaters represents a major problem for the environment, since heavy metal ions are nonbiodegradable, and tend to accumulate in the food chain, which causes varieties of serious health problems. They have remarkably high toxicity; some of them even have been confirmed to be carcinogenic [1-6]. Adsorption is generally preferred for the removal of heavy metal ions due to its high efficiency, easy handling, availability of different adsorbents and cost effectiveness [1-3, 5]. Many studies are dealing with adsorption and separation of metal with SIR [7]. Amberlite XAD have attractive features are easy regeneration for multiple sorptions-desorption cycles, good mechanical stability and reproducible sorption characteristics. The present paper investigates the adsorption of metal ions (Pb2+, Cu2+, Cd2+, Cr3+, Ni2+, Fe3+, Zn2+ and Ca2+) using the SIR prepared by impregnation of Amberlite XAD4 with an organophosphorous extractant D2EHPA. A separation method was developed for metals ions and was investigated the influence of contact time on the residual concentration of metal ions, on their removal efficiency and on the adsorption capacity of resin towards metal ions. MATERIALS and METODS The Amberlite XAD4 resin (supplied by Rohm and Hass Co.) was impregnated with D2EHPA trough dry method. The D2EHPA ~ 98.5% used as extractant, was supplied by

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BHD Chemicals Ltd Poole England and used as received. Impregnated XAD4 resin was obtained after method previous described [8]. One gram of fresh XAD4 has been placed for 24 h in ethanol (Chimopar Romania) containing 0.1 g/ml extractant (D2EHPA). The polymeric beads have been separated through a porous filter using a vacuum pump, washed with water and dried at 50°C for 24 h. Adsorption on the XAD4 support macro and interaction between the extractant and support has been emphasized by EDX and SEM analysis using a scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX) using an Inspect S scanning electron microscope. To study the effect of contact time on adsorption of metal ions for experiments was used samples of 0.1g Amberlite XAD4-D2EHPA impregnated resin were mixed at room temperature (27 °C) with 25 mL single metal solution containing 10 mg/L Me+ (where Me+ = Pb2+, Cu2+, Cd2+, Cr3+, Ni2+, Fe3+, Zn2+ and Ca2+) at several shake times (15, 30, 45, 60, 90 and 120min). Adsorption of metal ions on impregnated resin was studied in single component solutions and in solutions containing all cations (in this solution the concentration of each cation was of 10 mg/L). For batch experiments a mechanical shaker bath MTA Kutesz, Hungary was used. The suspensions were filtered and the concentration of metal ions in the filtrate was determined by means of atomic absorption spectrometry using a Varian SpectrAA 280 Fast Sequential Atomic Absorption Spectrometer with an air-acetylene flame at wavelengths λ=217 nm (Pb2+), λ =324.8 nm (Cu2+), λ=228.8 nm (Cd2+), λ=357.9 nm (Cr3+), λ=232 nm (Ni2+), λ=248.3 nm (Fe3+), λ=213.9 nm (Zn2+) and λ=422.7 nm (Ca2+). All other chemicals used for experiments were of analytical reagent grade, and were used without further purification. Distilled water was used in all experiments. RESULTS 1. Evaluation of the impregnation process Adsorption on the XAD4 support macro and interaction between the extractant and support has been emphasized by EDX and SEM analysis. The appearance and morphology of the external protective barrier was examined by scanning electron microscopy. The internal structure of the polymeric adsorbent (Amberlite XAD4) before and after the impregnation is shown in Figure1. The EDX spectrum of Amberlite XAD4 after impregnation is presented in Figure 2. One may notice the presence of the characteristic peak of phosphorus. This also proves the adsorption of D2EHPA on the XAD4 support.

(a) (b) Figure 1. SEM images of XAD4 (a) before impregnation Figure 2. EDX spectrum of and (b) after impregnation with D2EHPA XAD4–D2EHPA We may notice the presence of the characteristic peak of phosphorus and phosphorus content is 1.02%. 2. Retention of metal ions on XAD4-D2EHPA impregnated resin

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2.1. Retention of metal ions from single component solutions Experimental data regarding the influence of contact time on the adsorption capacity and on the efficiency of removal of metal ions on the XAD4-D2EHPA impregnated resin are shown in Figure 3. 100 90 2

Pb2+ Cd2+ Cr3+

1,5

Cu2+ Ni2+ 1

Fe3+ Zn2+ Ca2+

0,5

M etals rem o v al eff icien cy , %

M e tals ad so rp tio n cap acity , m g M e n + /g SIR

2,5

80

Pb2+

70

Cd2+

60

Cr3+ Cu2+

50

Ni2+

40

Fe3+

30

Zn2+

20

Ca2+

10 0

0 0

20

40

60

80

100

120

0

20

40

60

Time, min

80

100

120

Time, min

(a) (b) Figure 3. Influence of contact time on the metal ions adsorption capacity (a) and on the efficiency of removal of metal ions (b) from single component solutions The experimental data show the increase of the adsorption capacity and the efficiency of removal of metal ions as the contact time increases. Adsorption equilibrium and the efficiency of removal of metallic ions are reached after 60 minutes for all metal ions. The impregnated XAD4 resin with phosphate groups shows higher affinity for trivalent ion (Cr3+) and for divalent ion (Zn2+). One may notice that the efficiency of removal of metallic ions on XAD4D2EHPA impregnated resin, reaching values ~95% for Cr3+ and ~50% for Zn2+. For other metal ions studied the efficiency of removal is lower (<18%). 2.2. Retention of metal ions from mixed cation solutions Experimental data regarding the influence of contact time on the adsorption capacity and on the efficiency of removal of metal ions from solutions containing a mixture of cations on XAD4- D2EHPA impregnated resin is shown in Figure 4. 100

2

Pb2+ Cd2+ Cr3+

1,5

Cu2+ Ni2+ 1

Fe3+ Zn2+ Ca2+

0,5

Metals rem oval efficiency, %

M e ta ls a dsorption c a pa c ity, mg M e

n+

/g SI R

2,5

Pb2+

80

Cd2+ Cr3+

60

Cu2+ Ni2+

40

Fe3+ Zn2+

20

Ca2+

0

0 0

20

40

60

80

100

120

0

140

Time. min

20

40

60

80

100

120

T ime, min

(a) (b) Figure 4. Influence of contact time on the metal ions adsorption capacity (a) and on the efficiency of removal of metal ions (b) from mixed cation solutions The experimental data show the increase of the adsorption capacity and of the efficiency of removal of metal ions as the contact time increases. Adsorption equilibrium and the efficiency of removal of metallic ions are reached after 60 minutes for all metal ions. One may notice that the resin retains selectively for Cr3+ from the cationic mixture. Chromium is not affected by the presence of the other cations in solution; a ~ 95% removal efficiency was reached, as for the solution containing only Cr3+. For other metal ions from the mixture was observed that retention efficiencies are <7%, somehow lower than the values reached for single component solutions. CONCLUSIONS

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Amberlite XAD4 resin was impregnated with D2EHPA by dry method. The impregnation was evaluated by SEM and EDX analysis. These techniques proved the adsorption of D2EHPA on the XAD4 support. To study the possibility of using impregnated resin as adsorbent material in view to remove metal ions (Pb2+, Cu2+, Cd2+, Cr3+, Ni2+, Fe3+, Zn2+ and Ca2+) from solutions, solutions containing only one of the cations and solutions containing a mixture of all cations were used. In this aim, the influence of the contact time on the efficiency of retention and on the adsorption capacity of the resin was studied. The adsorption capacity and metal ions removal efficiency increased with the increase of contact time. Adsorption equilibrium and the efficiency of removal of metallic ions are reached after 60 minutes for all metal ions. It was observed that resin impregnated with phosphate groups shows affinity for trivalent ion (Cr3+) and for divalent ion (Zn2+) in solution with single component. At the same time, the adsorption process occurred with the best results when single component solutions were used. When mixed cation solutions were used, the efficiency of adsorption is somehow lower, due to competition between metal ions present in the solutions. Chromium was not affected by the presence of the other cations in solution; a ~ 95% removal efficiency was reached in both situations. ACKNOWLEDGEMENTS This work was partially supported by the strategic grant POSDRU/89/1.5/S/57649, Project ID 57649 (PERFORM-ERA), co-financed by the European Social Fund – Investing in People, within the Sectoral Operational Programme Human Resources Development 2007-2013. LIST OF REFERENCES [1] Hosseini-Bandegharaei A., Hosseini M.S., Sarw-Ghadi M., Zowghi S., Hosseini E., Hosseini-Bandegharaei H., (2010), Kinetics, equilibrium and thermodynamic study of Cr(VI) sorption into toluidine blue o-impregnated XAD-7 resin beads and its application for the treatment of wastewaters containing Cr(VI), Chemical Engineering Journal, 160, 190-198. [2] Navarro R., Saucedo I., Nunez A., Avila M., Guibal E, (2008), Cadmium extraction from hydrochloric acid solutions using Amberlite XAD-7 impregnated with Cyanex 921 (tri-octyl phosphine oxide), Reactive & Functional Polymers, 68, 557-571. [3] Navarro R., Gallardo V., Saucedo I., E. Guibal, (2009), Extraction of Fe(III) from hydrochloric acid solutions using Amberlite XAD-7 resin impregnated with trioctylphosphine oxide (Cyanex 921), Hydrometallurgy, 98, 257-266. [4] Xiong C., Yao C., Wang L., Ke J., (2009), Adsorption behavior of Cd(II) from aqueous solutions onto gel-type weak acid resin, Hydrometallurgy, 98, 318-324. from aqueous solutions, Chemical Engineering Journal, 155, 844-850. [5] Benamor M., Bouariche Z., Belaid T., Draa M.T., (2008), Kinetic studies on cadmium ions by Amberlite XAD7 impregnated resins containing di(2-ethylhexyl) phosphoric acid as extractant, Separation and Purification Technology, 59, 74-84. [6] Pehlivan E., Altun T., (2006), The study of various parameters affecting the ion exchange of Cu2+, Zn2+, Ni2+, Cd2+, and Pb2+ from aqueous solution on Dowex 50W synthetic resin, Journal of Hazardous Materials, B134, 149-156. [7] Draa M.T., Belaid T., Benamor M., (2004), Extraction of Pb(II) by XAD7 impregnated resins with organophosphorus extractants (D2EHPA, IONQUEST 801, CYANEX 272), Separation and Purification Technology, 40, 77-86. [8] Davidescu C. M., Ciopec M., Negrea A., Popa A., Lupa L., Negrea P., Muntean C., Motoc M., Use of Di-(2-Ethylhexyl) Phosphoric Acid (D2EHPA) Impregnated XAD7 Copolymer Resin for the Removal of Chromium (III) from Water, Rev. Chim. (Bucharest), 62(7), 2011

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STUDIES ON COLUMN ADSORPTION OF ARSENIC (V) FROM A REAL WATER ON DEHPA-IMPREGNATED XAD-8 RESIN Mihaela Ciopec1, Zoltán Galbács2, Gabor Galbács2, Adina Negrea1, Cornelia Muntean1*, Corneliu Mircea Davidescu1, Lavinia Lupa1 1

Faculty of Industrial Chemistry and Environmental Engineering, University „Politehnica” Timisoara, 2 Piata Victoriei, 300006 Timisoara, Romania, E-mail address: cornelia.muntean@chim.upt.ro; cornelia.muntean@yahoo.com 2 University of Szeged, Department of Inorganic and Analytical Chemistry, H-6701 Szeged, P.O.B. 440, Hungary

ABSTRACT Arsenic contamination of drinking water is a widespread problem of international interest. Arsenic is released from the soil through natural processes or due to human activities. In the paper was studied the possibility of removal of arsenic from drinking water using a column filled with Amberlite XAD-8 resin impregnated with di-(2-ethylhexyl) phosphoric acid (DEHPA). The efficiency of arsenic removal from water was established by studying the dependence of arsenic residual concentration and arsenic removal degree on the volume of the water passed over the adsorbent material. The adsorption process had an efficiency of ~90% and the arsenic residual concentration was smaller than 10 µg/L. The studies concerning the influence of other ions present in water (Na+, K+, Ca2+, Mg2+, Fen+, Mnn+, NO2-, NH4+, NO3-, PO43-, Cl-) showed that these ions do not interfere with arsenic adsorption process. KEY WORDS: column adsorption, arsenic, Amberlite XAD-8, impregnated resin, DEHPA INTRODUCTION Environmental protection is a matter of major interest, in order to preserve the ecological balance, to maintain and improve the quality of natural factors and to ensure the living and working conditions, adequate for present and future generations. Arsenic is an element that enters the environment from a variety of natural and anthropological sources. In underground and surface waters arsenic is present as arsenate (As5+) or arsenite (As3+). Arsenic is highly toxic and tends to be mobile in the environment. Contamination of drinking water with arsenic raises serious problems because of the effects of chronic arsenic poisoning. Chronic effects often include skin disease (pigmentation, skin cancer), cardiovascular disease, neurological, hematological, renal and respiratory diseases, and diseases of the lung, bladder, liver, kidney and prostate cancer. Most people affected by arsenic contamination are from poor backgrounds or small communities [1-3]. Removal of arsenic from drinking water is a major concern and urgency. Until now, several techniques were developed including processes of coagulation-precipitation, membrane separation, adsorption and ion exchange [3-13]. The paper presents studies on the removal of arsenic from drinking water using a column filled with Amberlite XAD-8 resin impregnated with di-(2-ethylhexyl) phosphoric acid (DEHPA). It was also studied the influence of other ions present in water on arsenic adsorption process.

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MATERIALS and METHODS For the adsorption of arsenic from the underground drinking water an Amberlite XAD-8 resin impregnated with di-(2-ethylhexyl) phosphoric acid (DEHPA) was used. The water sample used in experiments was analyzed to determine its composition before and after arsenic adsorption to study the influence of ions present in water on the adsorption process. For the experiments the resin was placed in a column of 30 cm height and 2 cm diameter. The height of adsorbent layer was of 5 cm. The underground water containing 80 µg As(V)/L was passed over the resin with a flow of 0.5 L/h. In order to establish the efficiency of arsenic removal from water it was studied the dependence of arsenic residual concentration and arsenic removal degree on the volume of the water passed over the adsorbent material. For the study samples of 25 mL from the effluent were collected. Arsenic concentration in the samples was determined by means of atomic adsorption spectrometry with hydride generation, using a VARIAN SpectrAA 110 spectrophotometer with a VARIAN VGA 77 hydride generation system. Concentrations of Na+, K+, Ca2+, Mg2+, Fen+ and Mnn+ were determined through atomic adsorption spectrometry, with a VARIAN SpectrAA 280FS spectrophotometer. NO2-, NH4+, NO3- and P2O5 were determined through UV-VIS spectrophotometry using a VARIAN Cary 50 spectrophotometer. Concentration of Cl− was determined by titration with AgNO3 solution, using K2CrO4 as indicator. The pH of the samples was measured using a CRISON Multimeter MM41. RESULTS 1. Analysis of underground water The results of the analysis of the initial underground water used in the adsorption studies are presented in Table 1. Data show that the water contains iron ions, which is an advantage for arsenic adsorption, due to the high affinity of arsenic towards iron [7-13]. pH of the water sample was of 7.3 and arsenic concentration was 80 µg/L. Table 1. Composition of the initial underground water Parameter, mg/L + + 2+ 2+ Na K Ca Mg Fen+ Mnn+ 91.8 2.5 26.9 16.1 2.0 0.6

NO20.6

NH4+ 1.5

NO340.2

P2O5 4

2. Dependence of arsenic removal efficiency on the volume of water Experimental data regarding the dependence of arsenic residual concentration and arsenic removal degree on the volume of water passed through the column are presented in Figs. 1.a and 1.b, respectively. The removal degree of As(V) ions from the water was calculated using the following equation: C − Cres η= i 100 (1) Ci where Ci and Cres are the initial and the residual concentrations of As(V), respectively. Data presented in Fig. 1.a show that after a volume of 1700 mL water passed through the column, arsenic residual concentration in the effluent remains constant and its value is smaller than the maximum permitted value for drinking water (10 μg/L). From Fig. 1.b one may notice that a ~90% removal degree was reached.

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3. Influence of other ions present in the underground water In Fig. 2 are presented for comparison the data for the chemical analysis of the water before and after treatment through adsorption in view of arsenic removal. One may notice that the other ions present in the initial water sample do not interfere with arsenic adsorption process on DEHPA impregnated XAD-8 resin. Data also show that some of these ions are adsorbed together with arsenate ions, their concentrations becoming somewhat smaller after passing through the column. It is especially the case of iron ions that are almost totally retained on the adsorbent material, their concentration becoming under the detection limit. 200

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In the present work was studied the possibility of removal of arsenic from drinking water using a column filled with Amberlite XAD-8 resin impregnated with di-(2-ethylhexyl) phosphoric acid (DEHPA). The efficiency of arsenic removal from water was established by studying the dependence of arsenic residual concentration and arsenic removal degree on the volume of the water passed

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through the column. The adsorption process had an efficiency of ~90% and the arsenic residual concentration was smaller than 10 µg/L. It was also studied the influence of other ions present in water (Na+, K+, Ca2+, Mg2+, Fen+, Mnn+, NO2-, NH4+, NO3-, PO43-, Cl-) on the process of arsenic adsorption. Some of these ions were adsorbed together with arsenate ions, but their adsorption did not interfere with arsenic adsorption process on DEHPA impregnated XAD-8 resin. ACKNOWLEDGMENTS

This work was partially supported by CNCSIS- UEFISCDI, project number PN II-IDEI 927/2008, “Integrated Concept about Depollution of Waters with Arsenic Content, through Adsorption on Oxide Materials, followed by Immobilization of the Resulted Waste in Crystalline Matrices”. This work was partially supported by the strategic grant POSDRU/89/1.5/S/57649, Project ID 57649 (PERFORM-ERA), co-financed by the European Social Fund – Investing in People, within the Sectoral Operational Programme Human Resources Development 2007-2013. LIST OF REFERENCES

[1] Environmental Protection Agency USA. (2000). Arsenic occurrence in public drinking water supplies. [2] Smedley P.L., Kinniburgh G. (2007). A review of the source, behaviour and distribution of arsenic in natural waters. Applied Geochemistry. 17(5), p. 517-568. [3] Borah D., Satokawa S., Kato S., Kojima T. (2008). Surface-modified carbon black for As(V) removal. Journal of Colloid and Interface Science. 319, p. 53-62. [4] Lazaridis N.K., Hourzemanoglou A., Matis K.A. (2002). Flotation of metal-loaded clay anion exchangers. Part II: the case of arsenates. Chemosphere. 47(3), p. 319-324. [5] Pinisakul A., Polprasert C., Porkplan P., Satayarirod J. (2002). Arsenic removal efficiency and mechanisms by electro-chemical precipitation process. Water Science and Technology. 46/9, p. 247-254. [6] Maji S.K., Pal A., Pal T. (2008). Arsenic removal from real-life groundwater by adsorption on laterite soil. Journal of Hazardous Materials. 151, p. 811- 820. [7] Lien H.-L., Wilkin R.T. (2005). High-level arsenite removal from groundwater by zerovalent iron. Chemosphere. 59, p. 377-386. [8] Guo H., Stuben D., Berner Z., Kramar U. (2008). Adsorption of arsenic species from water using activated siderite-hematite column filters. Journal of Hazardous Materials. 151(2-3), p. 628-635. [9] Thirunavukkarasu O.S., Viraraghavan T., Subramanian K.S. (2003). Arsenic removal from drinking water using granular ferric hydroxide. Water SA. 29(2), p. 161-170. [10] Guo H., Stuben D., Berner Z. (2007). Adsorption of arsenic (III) and arsenic (V) from groundwater using natural siderite as the absorbent. Journal of Colloid and Interface Science. 315, p. 47-53. [11] Zeng L.. (2003). A method for preparing silica-containing iron (III) oxide adsorbents for arsenic removal. Water Research. 37(18), p. 4351-4358. [12] Jeong Y., Fan M., Slingh S., Chuang C.-L., Saha B., van Leeuwen J. H. (2007). Evaluation of iron oxide and aluminum oxide as potential arsenic (V) adsorbents. Chemical Engineering and Processing. 46, p. 1030-1039. [13] Zhang Q.L., Lin Y.C., Chen X., Gao N.Y. (2007). A method for preparing ferric activated carbon composites adsorbents to remove arsenic from drinking water. Journal of Hazardous Materials. 148, p. 671-678.

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STUDIES ON THE PURIFICATION OF WASTEWATERS WITH HIGH NICKEL IONS CONTENT Petru Negrea1, Mihaela Ciopec1, Cornelia Muntean1*, Gabriela Gârban2, Lavinia Lupa1, Adina Negrea1 1

Faculty of Industrial Chemistry and Environmental Engineering, University „Politehnica” Timisoara, 2 Piata Victoriei, 300006 Timisoara, Romania, E-mail address: cornelia.muntean@chim.upt.ro; cornelia.muntean@yahoo.com 2 National Institute of Public Health - Branch Timisoara,Department of Environment and Nutrition, Bd. Dr. V. Babes Nr. 16, 300226 Timisoara, Romania

ABSTRACT The paper presents studies on the removal of nickel from wastewaters with high nickel ions content resulting from galvanizing process. In the first step of the purification process, nickel ions were precipitated using a 10 M NaOH solution as precipitation agent. By increasing the pH of the Ni2+ solutions up to 11, the residual concentration of nickel ions reached the values required for the discharge in sewerage and in water resources. Taking into account that this pH value does not allow the discharge, the solution resulting from the precipitation process at pH 9 was submitted in the second step to an advanced treatment using as adsorbent material an Amberlite XAD-4 resin impregnated with di-2(ethyl-hexyl) phosphoric acid. To establish the conditions for the adsorption process was studied the influence of contact time and of adsorbent dosage on the efficiency of nickel ions removal from the solution. The maximum efficiency of ~ 94% was reached after 90 min for an adsorbent dosage of 0.3 g:25 mL. The residual concentration of nickel ions was ~0.5 mg/L, value that allows the discharge in the sewerage and even in water resources. KEY WORDS: nickel, wastewater, XAD-4, impregnated resin, adsorption, DEHPA INRODUCTION Nickel is widespread in soil and plants. Nickel ore is mainly found in the form of sulphides, silicates and arsenide. Among the most toxic nickel compounds is nickel-carbonyl, which is a colorless liquid with a smell of soot and high volatility. This compound is used in industry to produce nickel alloys and some special steels resistant to corrosion and high temperatures; in nickel-plate baths; in the operations of metallization of contacts in electrical circuits. Nickelcarbonyl is also used to extract pure metal from ore and as catalyst in the plastics industry [1-6]. The rapid development of leading industries generated a huge demand for new materials with controlled properties. Of great importance in materials chemistry is getting some smart materials such as materials that react to environmental changes, because they open the way for new technologies. One of the most important properties of functionalized / impregnated materials is their easy processing which allows their use in many applications [7, 8]. The studies presented in paper aim the removal of nickel ions from wastewaters with high nickel ions content resulting from galvanizing process, in view of discharge in sewerage or in water resources. In the first step of the purification process, nickel ions were precipitated using a 10 M NaOH solution as precipitation agent. In the second step, the solution resulting

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from the precipitation process was submitted to an advanced treatment using as adsorbent material an Amberlite XAD-4 resin impregnated with di-2(ethyl-hexyl) phosphoric acid. MATERIALS and METHODS The wastewater resulting from galvanizing process was analyzed in order to determine its nickel ions content and its pH value. In order to establish the conditions for nickel removal through precipitation, samples of 100 mL wastewater were treated with 10 M NaOH solution until various final pH values of the suspensions were reached: 6, 7, 8, 9, 10, 11 and 12. The suspensions were filtered and the residual concentration of nickel ions in the resulting solutions was determined by means of atomic absorption spectrometry, using a Varian SpectrAA-280 FS spectrophotometer. The pH value of the samples was measured using a Denver Instrument pH-meter. In view of discharge, the solutions resulting from the precipitation process were submitted in the second step to an advanced treatment using as adsorbent material an Amberlite XAD-4 resin impregnated with di-2(ethyl-hexyl) phosphoric acid (DEHPA). The conditions for the adsorption process were established by varying the adsorbent dosage (S:L ratio = 0.1 g:25 mL; 0.2:25 and 0.3:25) and the contact time (15, 60, 90, 120 and 240 min). The samples were shaken with 150 strokes/min using a Shaker Bath – Kutesz Tip 609/A (Hungary). After contact time elapsed, the samples were filtered and the residual concentration of nickel ions in the resulting solutions was determined through atomic absorption spectrometry. RESULTS The analysis of the initial wastewater sample showed that it presented a high nickel ions concentration (43.6 g/L) and a pH value of 4.63. These results show that the wastewater cannot be discharged in water resources or in sewerage. In order to reach the discharge conditions this wastewater should be submitted to a purification process.

Ni2+ residual concentration, mg/L

1. Studies on the removal of Ni2+ through precipitation The experimental data regarding the dependence of the pH of the suspensions on the volume of precipitation agent are presented in Fig. 1. In Fig. 2 is given the dependence of the residual concentration of Ni2+ on the final pH of the suspensions.

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Fig. 1. Dependence of pH of the suspension on the volume of precipitation agent

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Fig. 1. shows that as the volume of precipitation agent added to the wastewater sample increases up to 75 mL NaOH/100 mL sample, the pH of the reaction mass also increases up to ~8. For volumes of precipitation agent between 75 and 100 mL/100 mL sample, the pH value remains practically unchanged. As the volume of precipitation agent further increases, the pH of the suspensions increases also up to 12. From data presented in Fig. 2 one may notice that the residual concentration of Ni2+ decreases as the final pH of the suspensions increases. At pH 11 the residual concentration of nickel ions was of 0.57 mg/L, which is smaller than the maximum permitted values by the Romanian legislation for the discharge in the sewerage (1 mg Ni2+/L) and close to the value for the discharge in water resources (0.5 mg Ni2+/L). Even if the residual concentration reached at pH 11 was under the maximum permitted values, this pH value does not allow the discharge. The same legislation specifies that the pH of the discharged water should be in the range 6.5 – 9. In the sample treated at pH 9 the residual Ni2+ concentration was ~10 mg/L, much higher than the permitted values. In view of discharge, the subsequent studies aimed the advanced removal of nickel ions from this solution through adsorption on DEHPA-impregnated XAD-4 resin. 2. Studies on the removal of Ni2+ through adsorption on DEHPA-impregnated XAD-4 resin Fig. 3 illustrates the influence of contact time between the Ni2+ solution and the adsorbent material on the efficiency of the adsorption process, for various adsorbent dosages. The efficiency of the adsorption process (the removal degree of nickel ions from the solution) was calculated using the following equation: C − Cres η= i 100 (1) Ci where Ci and Cres are the initial and the residual concentrations of Ni2+, respectively.

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Fig. 3. Dependence on the contact time of the efficiency of Ni2+ adsorption on DEHPA-XAD-4, for various adsorbent dosages Experimental data presented in Fig. 3 show that the efficiency of the adsorption process increases as the contact time increases up to 90 min, for all adsorbent dosages. As contact time further increases, the efficiency remains the same. The maximum efficiency of ~ 94% was reached for an adsorbent dosage of 0.3:25. In this situation, the residual concentration of nickel ions was ~0.5 mg/L, value which allows the discharge in the sewerage and even in water resources.

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CONCLUSIONS

The paper presents studies on the removal of nickel from wastewaters with high nickel ions content resulting from galvanizing process, in view of discharge in sewerage or in water resources. In the first step of the purification process, nickel ions were precipitated using a 10 M NaOH solution as precipitation agent. The wastewater samples were treated with the precipitation agent until various final pH values of the suspensions were reached: 6, 7, 8, 9, 10, 11 and 12. In the solution treated at pH 11, residual concentration of nickel ions reached the values required for the discharge in sewerage and in water resources, but this pH value does not allow the discharge. In view of discharge, the solution resulting from the precipitation process at pH 9 and containing 10 mg Ni2+/L was submitted in the second step to an advanced treatment using as adsorbent material an Amberlite XAD-4 resin impregnated with di-2(ethyl-hexyl) phosphoric acid. To establish the conditions for the adsorption process was studied the influence of contact time (15, 60, 90, 120 and 240 min) and of adsorbent dosage (S:L ratio = 0.1 g:25 mL; 0.2:25 and 0.3:25) on the efficiency of nickel ions removal from the solution. The maximum efficiency of ~ 94% was reached after 90 min for an adsorbent dosage of 0.3 g:25 mL. The residual concentration of nickel ions was ~0.5 mg/L, value that allows the discharge in the sewerage and even in water resources. LIST OF REFERENCES

[1] Neniţescu C.D. (1985). General chemistry (in Romanian). 5th Ed. Bucharest. Didactică şi Pedagogică Publishing House. [2] Patriciu V. (1983). Nickel and cobalt (in Romanian). Bucharest. Tehnică Publishing House. [3] Negulescu M. (1989). Purification of industrial wastewaters (in Romanian). Bucharest. Tehnică Publishing House. [4] Gergely A., Bay E., Dumitrescu M. (1992). Treatment of wastewaters and recovery of electrolytes in electroplating (in Romanian). Bucharest. Tehnică Publishing House. [5] Negrea P., Negrea A., Muntean C., Lupa L., Antonescu M. (2006). Studies about nickel ions elimination from residual waters resulted from nickel coat baths. Sci. Bull. “Politehnica” Univ. (Timisoara), Trans. Mec. 51(65), p. 133-136. [6] Negrea P., Lupa L., Negrea A., Jievariu L. (2005). Studies about nickel ions elimination from residual waters. Proceedings of “The 12th Symposium on Analytical and Environmental Problems” SZAB, Szeged (Hungary), Sept 26, p. 78-82. [7] Popa A. (2009). Polymers functionalized with groups with phosphorus and nitrogen (in Romanian). Timisoara. Univ. de Vest Publishing House. [8] Cortina J.L., Warshawsky A. (1997). Developments in Solid-Liquid Extraction by Solvent-Impregnated Resins, in: Ion Exchange and Solvent Extraction, Marinsky J.A. and Marcus Y., (Eds.), Vol. 13, Marcel Dekker, New York, p. 195-293.

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STUDIES REGARDING THE TURNING TO ACCOUNT OF THE WASTE RESULTING FROM COAL EXPLOITATION Adina Negrea1, Gabriela Garban2, Mihaela Ciopec1, Cornelia Muntean1*, Petru Negrea1, Ioneta Dragomir1 1

Faculty of Industrial Chemistry and Environmental Engineering, University „Politehnica” Timisoara, 2 Piata Victoriei, 300006 Timisoara, Romania, E-mail address: cornelia.muntean@chim.upt.ro; cornelia.muntean@yahoo.com 2 National Institute of Public Health - Branch Timisoara,Department of Environment and Nutrition, Bd. Dr. V. Babes Nr. 16,300226 Timisoara, Romania

ABSTRACT In this paper was studied the possibility of turning to account of the waste resulting from coal mining. One way was to use the waste in order to stabilize ash dumps. The chemical analysis of the coal waste and ash showed that both have high zinc and nickel content. As remediation method was chosen for this study the cultivation of barley as bio-indicator plant on substrates obtained by mixing the coal waste and ash in various proportions. After bio-remediation, the zinc content of the substrates fell under the maximum permitted value for all coal-ash mixtures. The nickel content decreased very much, but remained somewhat higher than the maximum permitted value. Another way was to use waste material as adsorbent in view of removal of organic dyes from wastewaters resulting from inkjet cartridge remanufacturing. The coal waste was used in various dosages (S:L = 0.1 g:25 mL; 0.2:25; 0.3:25; 0.4:25 and 0.5:25) and the suspensions were shaken for various contact times (15, 30, 45, 60 and 120 min). The highest removal efficiency ( ~60%) was reached for a S:L ratio of 0.5:25 after a 60 min contact time. KEY WORDS: coal waste, stabilization, adsorption, organic dyes INTRODUCTION In the last decades environmental issues occurred in mining. These problems are associated with sulphide ore mining in view of metals extraction, and with coal exploitation. Human activities, especially mining, metallurgical and chemical industry, led to the transformation of once fertile land into real deserted areas [1, 2]. After coal mining wastes result that can be used either as fertilizer or for the stabilization of ash and sterile dumps and even as adsorbent materials in the treatment of some wastewaters. In general, ink jet printers use dyes diluted in water. This can create problems on the disposal of wastewater resulting from washing. The removal of organic dyes from such wastewaters can be done by using adsorbent materials [2-8]. In this paper was studied the possibility of turning to account of the waste resulting from coal mining. One way was to use the waste in order to stabilize ash dumps. Another way was to use waste material as adsorbent in view of removal of organic dyes from wastewaters resulting from inkjet cartridge remanufacturing.

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MATERIALS and METHODS In view to include the studied waste resulting from coal mining into a certain wastes category, the material was submitted to the leaching test, according to the legislation [9]. The waste was also submitted to chemical and physico-chemical analysis [10] in view of using it as substrate for growing plants. The waste was used as substrate for growing plants; it was mixed in various proportions with ash. The mixtures were places in vessels and as bio-indicator plant was cultivated barley. The vessels were kept 30 days in laboratory, and watered with drinking water every three days. After 30 days, the plants were harvested. In order to determine the metals content of the substrates used for cultivation, the samples were brought into solution by boiling until almost dry with a mixture of concentrated hydrochloric acid and concentrated nitric acid HCl : HNO3 = 1 : 3. The residue was treated with water and filtered. The concentration of metal ions in the filtrate was determined by means of atomic absorption spectrometry, using a VARIAN SpectrAA 280FS spectrophotometer. The removal of organic dyes from wastewaters resulting from inkjet cartridge remanufacturing was carried out using the waste as adsorbent material in various dosages (S:L = 0.1 g:25 mL; 0.2:25; 0.3:25; 0.4:25 and 0.5:25). The suspensions were shaken with 150 strokes/min for various contact times (15, 30, 45, 60 and 120 min) using a Shaker Bath – Kutesz Tip 609/A (Hungary). After the desired contact time elapsed, the suspensions were filtered. The resulting solutions were submitted to UV-VIS spectrometric analysis. The UVVIS spectrum of the initial wastewater showed five absorption bands with maxima at 380, 406, 516, 563.7 and 628.5 nm corresponding to five different colors. For measurements was chosen the band at 628.5 nm that was the most intense. For absorption measurements a Varian Cary 50 UV-VIS spectrophotometer was used. RESULTS 1. Characterization of the waste resulting from coal mining The experimental data obtained by the leaching test showed that the waste is inert and it can be stored. The results of chemical and physico-chemical analysis are the following: - the waste is acidic (pH = 4.71); - the exchangeable base content (10 meq/100 g material) is within the normal range for Romania (1-50 meq/100 g material); - high hydrolytic acidity (19.7 meq/100 g material); - carbonates content is low (< 20 g/kg d.m.); d.m. = “dry material” - the density (1-2 g/cm3) is typical for humus rich soils; - the macronutrients content is high (N-6.4%, P-445 mg/kg d.m., K-177 mg/kg d.m.). These data allowed us to conclude that the waste presents the characteristics of peat coal, having acidic properties and typical density. At the same time, due to its high macronutrients content, the waste has fertilizing properties. 2. Studies regarding the use of the waste resulting from coal mining in view of ash dumps stabilization The data obtained from the chemical analysis of the coal waste and ash showed that both have high zinc (waste – 586 mg/kg d.m.; ash – 455 mg/kg d.m.) and nickel (waste – 252 mg/kg d.m.; ash – 134 mg/kg d.m.) content, which indicates the need for application of remediation methods. As remediation method was chosen for this study the cultivation of barley as bioindicator plant.

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The experimental data regarding the zinc and nickel content of the substrates used for cultivation, after bio-remediation, are presented in Fig. 1. After bio-remediation the zinc content of the substrates fell under the maximum permitted value for all coal-ash mixtures. For all mixtures used as substrates for barley cultivation, the nickel content after bio-remediation decreased very much, but remained somewhat higher than the maximum permitted value.

Ni2+ content, mg/kg d.m.

Zn2+ content, mg/kg d.m.

60

100

50

0

40

20

0 10 cm ash + 2 cm coal

coal

1/4 coal + 3/4 3/4 coal + 1/4 1/2 coal + 1/2 ash ash ash

MPV

10 cm ash + 2 cm coal

coal

Substrate

1/4 coal + 3/4 3/4 coal + 1/4 1/2 coal + 1/2 ash ash ash

MPV

Substrate

(a) Zinc content

(b) Nickel content

Fig. 1. Zinc and nickel content of substrates after bio-remediation

Dyes removal efficiency, %

3. Studies regarding the use of the waste resulting from coal mining as adsorbent material Fig. 2 illustrates the influence of contact time between the wastewater containing dyes and the coal waste on the dyes removal efficiency, for different adsorbent material dosages. One may notice that the removal efficiency increased abruptly as the contact time was increased up to 60 min, but then remained constant as the equilibrium was attained. The removal efficiency increased as the adsorbent dosage increased; the highest value was reached for a S:L ratio of 0.5:25 ( ~60%).

60

S:L=0.1:25 S:L=0.2:25 S:L=0.3:25 S:L=0.4:25 S:L=0.5:25

40

20

0 0

20

40

60

80

100

120

Time, min

Fig. 2. Influence of contact time on dyes removal efficiency, for different adsorbent material dosages

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CONCLUSIONS In this paper was studied the possibility of turning to account of the waste resulting from coal mining. One way was to use the waste in order to stabilize ash dumps. The chemical analysis of the coal waste and ash showed that both have high zinc and nickel content, which indicates the need for application of remediation methods. As remediation method was chosen for this study the cultivation of barley as bio-indicator plant on substrates obtained by mixing the coal waste and ash in various proportions. After bio-remediation, the zinc content of the substrates fell under the maximum permitted value for all coal-ash mixtures. The nickel content after bio-remediation decreased very much, but remained somewhat higher than the maximum permitted value. Another way was to use waste material as adsorbent in view of removal of organic dyes from wastewaters resulting from inkjet cartridge remanufacturing. The waste was used in various dosages (S:L = 0.1 g:25 mL; 0.2:25; 0.3:25; 0.4:25 and 0.5:25) and the suspensions were shaken for various contact times (15, 30, 45, 60 and 120 min). The highest removal efficiency ( ~60%) was reached for a S:L ratio of 0.5:25 after a 60 min contact time. Our studies allowed us to conclude that the waste resulting from coal mining may be turned to account as fertilizer, or by using it for the stabilization of ash dumps, or as adsorbent material, without any previous treatment. LIST OF REFERENCES [1] Neag Gh. (1997). De-pollution of Soils and Underground Waters (in Romanian). Bucharest. Casa Cărţii de Ştiinţă Publishing House. [2] Pietraru J. (1982). Dumps for Storage of Sludge, Ashes, Slag, Sterile and Household Wastes (in Romanian). Bucharest. Tehnică Publishing House. [3] Drage G., Tamms O. (2000). Pigment Coating & Surface Sizing of Paper. Helsinki, Finland. in: Lehtinen E. (Ed.). Papermaking Science & Technology Series. Vol. 11. The Finnish Paper Engineers' Association & TAPPI. [4] Gaudreau M., Brazeau L. (2003). GC Method for Ink Dating Analysis. Internal communication. [5] Floru L., Urseanu F., Tărăbăşanu C., Palea R. (1980). Chemistry and Technology of Aromatic Intermediaries and Organic Dyes (in Romanian). Bucharest. Didactică şi Pedagogică Publishing House. [6] Ahmad A.L., Loh M.M., Aziz J.A.. (2007). Preparation and characterization of activated carbon from oil palm wood and its evaluation on Methylene blue adsorption. Dyes and Pigments. 75, 263-272. [7] Hameed B.H. (2009). Evaluation of papaya seeds as a novel non-conventional low-cost adsorbent for removal of methylene blue. Journal of Hazardous Materials. 162, 939-944. [8] Elizalde-González M.P., Hernández-Montoya V. (2009). Guava seed as an adsorbent and as a precursor of carbon for the adsorption of acid dyes. Bioresource Technology. 100, 2111-2117. [9] Official Monitor no. 184 bis / March 8 2005. [10] Muntean C., Negrea A., Lupa L., Ciopec M. (2009). Chemical and physico-chemical analysis with applications in environmental protection (in Romanian). Timişoara. Politehnica Publishing House.

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ELECTROCHEMICAL SYNTHESIS OF POLY-3-AMINOPHENYL BORONIC ACID IN SULFURIC ACID SOLUTION Pleşu Nicoleta1, Kellenberger Andrea2, Popa Iuliana3, Ţăranu Bogdan3, Ţăranu Ioan3, Ţara-Lungă Mihali Milica1 1

Institute of Chemistry of the Romanian Academy, Mihai Viteazul Blvd.24, Timisoara, Romania 2 University “Politehnica” of Timisoara,Faculty of Industrial Chemistry and Environmental Engineering, P-ta Victoriei 2, 300006 Timisoara, Romania 3 National Institute of Research-Development for Electrochemistry and Condensed Matter Timişoara, Romania 300569, Dr. A.P. Podeanu Str. 144 e-mail: plesu_nicole@yahoo.com ABSTRACT Sensors based on the complexation of boron groups with diols are an attractive alternative to detection of biologic compounds in particular dopamine. The electropolymerisation of 3aminophenylboronic acid (APBA) in aqueous solutions on Pt electrodes has been investigated. The obtained poly-3-aminophenylboronic acid is used for the potentiometric detection of dopamine. INTRODUCTION Electrochemical sensors based on conducting polymers offer many advantages and new possibilities to detect biologically significant compounds. A most intensively investigated conducting polymer due to its excellent stability in different solutions, good electronic properties, and strong biomolecular interactions is polyaniline (PANI) [1]. Various sensors and biosensors, such as enzyme sensors, DNA sensors and immunosensors based on PANI are reported.[2,3] The emeraldine salt (ES) form is the only conducting state among the four basic states of PANI and can be obtained in acidic conditions (pH = 2.5 ~ 3.0). The pH sensitivity seems unfavourable for application in biosensors, because most bioassays must be performed in neutral or slightly acidic conditions. In order to overcome this disadvantage, functionalization strategies were adopted. Some research used N-substituted anilines instead of PANI and reveals that the alkyl chain, which is covalently bounded to the nitrogen atom, prevents formation of the EB form, and finally the obtained polymer do not have pH sensitivity [4]. Another derivative of PANI, self-doped PANI, which is usually known as sulfonated PANI, shows redox activity even in solutions with neutral pH [5]. Sulfonated PANI was used in amperometric biosensors [6]. It has also been demonstrated that the blends of PANI that included negatively charged co-components such as sulfonic acid or polyacrylic acids exhibit redox activity in neutral aqueous solutions [7]. The presence of boron moiety in PANI chain generated poly(aniline boronic acid) PABA [8] a polymer which exhibits redox activity also in solutions with neutral pH. PABA was used in the detection of fluoride [9], saccharides [10], and dopamine [11] based on analyte interactions with the boronic acid functionality. In this work, PABA has been electrochemically synthesized and explored as a sensing material for dopamine.

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MATERIALS and METHODS Materials and reagents 3-Aminophenylboronic acid hydrochloride (APBA), aniline, dopamine (DA) and sodium fluoride were purchased from Aldrich Chemical Inc. Double distilled water and analytical grade sulphuric acid was used to prepare the electrolyte solutions. PABA electropolymerization The electrochemical polymerization of APBA was carried out by cyclic voltammetry using an Autolab PGSTAT 302N. All measurements were performed in a conventional onecompartment, three-electrode electrochemical cell equipped with a Pt disc working electrode (A = 1 cm2), two graphite rods as counter electrode and an Ag/AgCl electrode as reference electrode. Cyclic voltammograms were recorded at a scan rate of 100 mV s-1 in 0.5 M H2SO4 solutions with 0.3 M NaF and 0.01 M APBA and respectively 0.03 M APBA. For the first ten cycles the potential range was from –0.2 V to 1.2 V to allow the initiation of the polymerization process, afterwards the reversal potential was decreased to 0.8 V to avoid the overoxidation reactions of the polymer chain. The redox activity of the PABA film was investigated by cyclic voltammetry in a monomer free 0.5 M H2SO4 solution. RESULTS The cyclic voltammograms recorded during the electropolymerization of APBA in 0.5 M H2SO4 solution are given in Figure 1. The anodic potential limit was set to 1.2 V for the first 10 scans to initiate the polymerization process, afterwards it was lowered to 0.8 V and the potential was cycled between –0.2 and 0.8 V for the next 20 scans. It has been observed that in the absence on NaF no oxidation of the monomer took place.

a) b) Figure 1. The electropolymerization of a) 0.03 M and b) 0.01M APBA in 0.5 M H2SO4 and 0.3M NaF. The complexation of fluoride with the boronic acid moiety substantially reduced the oxidation potential required for polymerization process. The shape of the cyclic voltammograms for APBA polymerization resembles closely that of aniline polymerization. For higher monomer concentration the first anodic peak increases during consecutive cycling which is an indication of the polymer film growth. At lower

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monomer concentration, the first anodic peak increases to a smaller extent, indicating that the polymerization rate is proportional to the monomer concentration. The redox behavior of PABA film was recorded in monomer free electrolyte solutions (Figure 2). The three redox peaks corresponding to redox transitions similar to PANI indicate that the obtained film is electroactive. Its color changes from light green to dark blue in dependence of the applied potential.

Figure 2. Cyclic voltammograms of PABA in 0.5 M H2SO4 solution at 100 mV s-1 scan rate. The obtained PABA film was tested as a sensor for dopamine. The potentiometric calibration curve obtained in dopamine solutions with different concentrations is given in Figure 3.

Figure 3. The potentiometric response of PABA electrode for dopamine The gradual change in potential observed in Figure 3 is due to the effect of boronic acid complexation on the electrochemical potential, due to the increase in electron density ortho to the boronate complex, affecting the Ka of the protonated amine [12]. At micromolar range concentration of DA used in this study, the formation of a small amount of anionic ester induce an observable potential shift as a result of boronic acid-diol complexation (Scheme 1). HO *

n

*

+

R'

*

HO

-

B

B

HO

n

OH

HO

*

+

HOH

+

+

H

O O

R'

Scheme 1 The electrochemical potential is sensitive to the change in the pKa of the PABA, the response for DA concentration is linear between 10-1 to 10-4 mol L-1. PABA

DA

Acid-diol complex

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CONCLUSIONS - the electrochemical polymerization of APBA on platinum takes place similarly to the electrochemical synthesis of polyaniline. - at lower monomer concentrations the first anodic peak doesn’t increase linearly with the number of scans, indicating that the film growth is obstructed. - at higher monomer concentrations the peak current is almost 30 timer higher, indicating the formation of a much thicker polymer film. - the presence of NaF is necessary because complexation of fluoride with the boronic acid moiety substantially reduced the oxidation potential required for polymerization, - the PABA sensor shows a linear response for dopamine concentrations between 10-1 to 10-4 mol L-1. Acknowledgments This work was supported by the Romanian Ministry of Education, Research and Innovation through PNCDI 2 Program nr. 72-171/2008 which is gratefully acknowledged. LIST OF REFERENCES [1] MacDiarmid A. G., Epstein A. J. (1989). Polyanilines: a novel class of conducting polymers, Faraday Discuss. Chem. Soc. 88, p. 317-332. [2] MacDiarmid A.G., Chiang J.C., Halpern M., Huang W.S., Mu S.L., Somasiri N.L.D., Wu W., Yaniger S.I. (1985) Polyaniline: interconversion of metallic and insulating forms, Mol. Cryst. Liq. Cryst. 121, p.173–180. [3] Imisides M.D., John R. amd Wallace G.G.(1996). Microsensors based on conducting polymers. Chemtech. 261, p. 9-25. [4] Lindfors T. and Ivaska A. (2002). Potentiometric and UV-vis characterisation of N-substituted polyaniline. J. Electroanal. Chem..535, p. 65-74. [5] Márquez A.G.C, Luz María Torres Rodríguez L.M.T, Rojas A.M. (2007). Synthesis of fully and partially sulfonated polyanilines derived from ortanilic acid: An electrochemical and electromicrogravimetric study. Electrochimica Acta. 52, 16, p. 5294-5303. [6] Ngamna O., Morrin A., Moulton S.E., Killard A.J., Smyth M.R. and Wallace G.G. (2005). An amperometric polyaniline enzyme biosensor fabricated from nanoparticles. Electroanalysis. 17, 5-6, p. 423-430. [7] Shi L.X., Xiao Y., Willner I. (2004). Electrical contacting of glucose oxidase by DNA-templated polyaniline wires on surfaces. Electrochem. Commun. 6, 1057-1060. [8] Fabre B., Taillebois L. (2003) Poly(aniline boronic acid)-based conductimetric sensor of dopamine, Chem. Commun. p. 2982–2983. [9] Nicolas M., Fabre B., Marchand G., Simonet J. (2000). New boronic acidand boronate-substituted aromatic compounds as precursors of fluorideresponsive conjugated polymer films. Eur. J. Org. Chem. p. 1703–1710. [10] Shoji E., Freund M.S. (2002). Potentiometric saccharide detection based on the pKa changes of poly(aniline boronic acid). J. Am. Chem. Soc. 124 p. 12486–12493. [11] English J.T., Deore B.A., Freund M.S. (2006), Biogenic amine vapour detection using poly(anilineboronic acid) films. Sens. Actuators B. 115, p. 666-671. [12] Muetterties (1967) E. L. The Chemistry of Boron and its Compounds; Wiley: New York, p. 495-500.

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THERMAL BEHAVIOR OF THE COPOLYMERS BASED ON STYRYLPHOSPHONIC ACID Lavinia Macarie, Nicoleta Plesu, Smaranda Iliescu, Adriana Popa, Gheorghe Ilia Institute of Chemistry Timisoara of the Romanian Academy, 24 Mihai Viteazu Bv, 300223 Timisoara, Romania ABSTRACT The main property of copolymers containing phosphonic acid group at side chain is the proton conductivity, therefore there copolymers have strong metal complexation properties, due to the presence of phosphonic group. The copolymers of styrylphosphonic acid and acrylic monomer at different molar ratios were synthesized by thermal polymerization and charcterized by FTIR, thermal analysis and ionexchange capacity. The copolymers present good ion-exchange capacity and can be used as potential ion exchangers. INTRODUCTION Functionalized crosslinked polymers have gained a great importance in many fields of scientific research as well as for industrial applications, due to their chemical and physical enhanced properties. The presence of functional active phosphonic group in the stucture of polymers makes them useful as ion-exchangers, able of retaining various metal ions or radioactive isotopes from waste water [1]. The functional groups in this type of polymers may be introduced as side groups, chain-end, in-chain, block or graft structures and their synthesis means the chemical modification of the already defined polymers or by direct polymerization of the functionalized monomers [2]. Both, vinylphosphonic acid homopolymer and its copolymers are the basis of many products which have found applications as essential components for the polymer electrolyte membranes, used in fuel cell development [3, 4] In the previous work we synthesized copolymers of vinylphosphonic acid as membranes with potential application as ion exchangers [5]. The aim of this work is to synthesized ion-exchange copolymers with phosphonic acid groups as side groups, starting from styryl phosphonic acid and acylate monomer, at different composition. The homopolymer of styrylphosphonic acid has no proper physico-mechanical properties to be used as ion-exchanger, hence, the copolymerization with suitable comonomer is needed. The copolymers were characterized by FTIR, thermal analysis and ionechange capacity. MATERIALS and METHODS Materials Styrylphosphonic acid (2-phenylethenyl phosphonic acid) (>98%) was obtained from Aldrich. The acrylic co-monomer is a mixture of a commercial products from Cognis: Photomer 3015, alifatic bisphenol A diacrylate oligomer (95%) and Photomer 3016F, trimethylolpropane triacrylate (5%). The role of Photomer 3016F is to assure the fluidization of Photomer 3015 which is very viscous and as crosslinking reagent. Thermal initiator azobisisobutyronitrile was

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obtained from Merck. HCl 0.01M solution was used as received. NaCl 2M solutions were prepared. Copolymer synthesis The copolymers were obtained by radicalic thermal polymerization. The photopolymerizable formulation contain monomer styrylphosphonic acid (SPA), co-monomer Photomer 3015/Photomer 3016F (PHA) at different ratios, from 1:1 to 5:1, and intiator 2% (w/w versus monomers). The polymerization was performed in sealed teflon tube, in oven at a temperature of 100oC, during 8 hours. Characterization of the copolymers Fourier transform infrared spectra (FT-IR) of the polymers were recorded, using Model Jasco FT/IR-4200 apparatus, in KBr pellet, following the band corresponding to the phosphonic groups and the decrease of the band corresponding to the C=C group of monomers, due to the polymerization. The decomposition process and thermal stability of the copolymers were invesigated using Mettler-Toledo thermogravimetric analyzer (TGA-DTA). The TGA mesurement were carried out under nitrogen atmosphere at a heating rate of 100C/min, from room temperature to 7500C. Approximately 20 mg in weight of the samples were used in each analysis and the gas flow rate was kept at 90 mL min-1. Ion exchange capacity is determined by measuring the amount of specified counter-ions in the membrane by titration after ion exchange with other ions or elution, using a suitable indicator. The ion exchange capacity was determined as follows: the known amount of membrane was immersed in 2N NaCl solution for one hour to obtain sodium form and release protons. The resulting solution was titrated with 0.01N NaOH. The volume of NaOH used to reach the end point (VNaOH), the concentraton of the NaOH solution used ([NaOH]) and the dry weight of the membrane (Wmembrane) were needed to calculated the ion exchange capacity (equation 1) [6]. IEC = (VNaOH x [NaOH] / Wmembrane) x 1000

(1)

Ion exchange capacity is defined as the milimolar equivalents of reactive (O)P(OH)2 sites per gram of polymer, of mmeq/g. The measured ion exchange capacity values are compared to the theoretical ion exchange capacity value, based on the moles of phosphonic groups from copolymer [7]. RESULTS The obtained copolymers are white to light brown colored materials, hard and brittle. The FTIR spectra confirmed that the polymerization occurred almost completely. In Figure 1 is presented, for exemple, the FTIR spectrum of PHA:SPA 1:3. In this spectrum can be identified the charactristic bands of P-OH at 952 cm-1, P=O of phosphonic acid group at 1182 cm-1, and phosphonic group at 1126 and 1240 cm-1. Also, an enlarged band of phosphonic acid group can be observed at 3443 cm-1. The FTIR spectrum of the copolymer PHA-SPA 1:3 showed the decrease of the absorption bands attributed to C=C at 1404 cm-1 and 821 cm-1 in comparison with monomers spectra, because the polymerization occured. The band at 1728 cm-1 corresponds to C=O group from acrylate, and the bands at 2876 and 2956 cm-1 are attributed to aromatic group. Using thermogravimetric analysis, samples were investigated under an inert environment (nitrogen). Figure 2 shows the overlayof TG curves of copolymers PHA-SPA at different compositions. The degradation temperature of styrylphosphonic acid reported in literature is

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around value of 200oC [8], and the degradation temperature of PHA is around value of 310oC [5].

Figure 1. FTIR spectrum of the copolymer PHA:SPA 1:3.

The results reveal that the thermal stability of the copolymers was changed by the modification of the ratio between co-monomers. Table 1 shows their decomposition temperatures of the first and second stages (Td1 and Td2) and the residue amount at 750oC. Table 1. Phosphorus content and thermal decomposition temperatures of the copolymers. P content (%) a

Sample

Td1 (oC)

Td2 (oC)

PHA-SPA 1:1 4.64 345,13 PHA-SPA 1:2 3.64 292,95 PHA-SPA 1:3 2.99 271,09 PHA-SPA 1:4 2.54 274,74 PHA-SPA 1:5 2.21 288,09 a Determined by Schoniger method

472,31 469,19 415,19 402,26 432,64

Residue at 750oC (%) 34,49 36,95 37,89 37,07 37,19

IEC (mmeq/g) 0.14 0.37 0.43 0.52 0.65

The TGA curves for copolymers of styryl phosphonic acid - acrylic monomers at different molar ratios, performed in nitrogen, are shown in Fig. 2. There a two steps of decompositions for all copolymers. The initial mass loss begins at about 200oC and this first step ends at about 370oC in the case of PHA-SPA 1:1 and at about 340oC for the others copolymers. The major mass loss in the first stage was recorded at Td1 (Table 1). 28

PHA-SPA 1-1 PHA-SPA 1-2 PHA-SPA 1-3 PHA-SPA 1-4 PHA-SPA 1-5

26 24 22 20

Mass, mg

18 16 14 12 10 8

Figure 2. TG curves of copolymers PHA-SPA.

6 4 2 0 0

50

100

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550

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Temperature, grdC

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The second stage occurs between 370oC and 550oC for copolymer PHA-SPA 1:1 and between 340oC and 500oC for the others with a less mass loss, at Td2. The distruction process led to the non-volatile residue, at 750oC (Table 1) consists of simple compounds (e.g.phosphorus oxide) and to a carbon frame representing the carbonized product (raw carbon) [9]. It can be observed that by increase of amount of SPA in the polymerizable formulation the thermal stability decreased, because the temperature of decomposition of copolymer decreased. It can be explained by the low reactivity of SPA monomer, and by increase the amount of SPA in polymerizable formulation it is the possibility to obtain copolymer with lower molar mass. The ion exchange capacity is a measure of the number of ionic groups (phosphonic acid) per gram of polymer. As is seen from Table 1 the IEC increased by the increase of amount of SPA, that means a higher reactivity of copolymer as ion exchanger. CONCLUSIONS The synthesized copolymers based on styrylphosphonic acid and acrylic monomers at different molar ratios, by thermal initiated radical polymerization, were characterized by FTIR, thermal analysis and ion-exchange capacity. By the increase of amount of styrylphosphonic acid in the composition of copolmers, the thermal stability decreased. The ion exchange capacity, which is the important property of these polymers, increased with the increase of the amount of stylyphosphonic acid by number of active phosphonic acid groups. The copolymers based on styrylphosphonic acid can be applied as ion-exchangers. Acknoledgements The authors are grateful for partial financial support for the synthesis and characterization of polymers from the Program no. 2, Project no.2.4. of the Romanian Academy, Institute of Chemistry Timisoara.

LIST OF REFERENCES [1] [2] [3] [4] [5]

[6] [7] [8]

Rivas B.L., Pereira E., Gallegos P., Homper D., Geckeler K.E. (2004). Metal Ion Binding Capability of the Water-Soluble Poly(Vinyl Phosphonic Acid) for Mono-, Di-, and Trivalent Cations. Journal of Applied Polymer Science. 92, p. 2917–2922. Frechet J.M.J. (2005). Functional polymers: from plastic electronics to polymer-assisted therapeutics. Prog. Polym Sci. 30, p. 844-857. Yamada M., Honma I. (2005). Anhydrous proton conducting polymer electrolytes based on poly (vinylphosphonic acid)-heterocycle composite material. Polymer. 46, p. 2986–92. Macarie L. Ilia G. (2010). Polyvinylphosphonic acid and its derivatives. Progess in Polymer Science. 35 p. 1078–1092. Macarie L., Tompa A., van der Walt N., Plesu N., Ilia G., Iliescu S., Popa A., Mihali M. (2010). Synthesis and characterization of poly(vinylphosphonic acid) organic polymers. Proceedings of New trends and strategies in the chemistry of advanced materials with relevance in biological systems, technique and environmental protection, p. 40-43. Strathmann H. (2004). Ion-Exchange Membranes Sepration Processes. In: Membrane Science and Technology, Series 9, Elsevier, p.121. Savard O. (2006). Proton Conducting Polymer Membranes. PhD Thesis, Simon Fraser University, Burnaby, Canada, p.54. Jiang D.D., Yao Q., McKinney M.A., Wilkie C.A. (1999) TGA/FTIR studies on the thermal degradation of some polymeric sulfonic and phosphonic acids and their sodium saltsPolym. Degrad. Stabil., 63, p. 423-434.

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DOES AN AROMATIC CHLORIDE SUBSTITUTE POSITION INFLUENCE THE AGGREGATION PROPERTIES OF DIRECT DYES? Muntean Simona Gabriela1, Grad Maria Elena1, Simu Georgeta Maria2 1

Institute of Chemistry Timisoara of Romanian Academy, B-dul Mihai Viteazul 24, 300223 Timisoara, Romania; 2 University of Medicine and Pharmacy “V. Babeş” Timişoara, Faculty of Pharmacy, Eftimie Murgu 2, 300041 Timişoara, Romania; e-mail: SGMUNTEAN@ACAD-ICHT.TM.EDU.RO ABSTRACT Dyes ions have a tendency to self-associate in aqueous solutions. The main factors influencing aggregation are dye concentration, electrolyte concentration, and temperature. In the present work, the influence of the chloride position in the dye structure on the dye aggregation was investigated. The molecular aggregation has been studied spectrophotometrically in aqueous solutions as a function of dye concentration (10-6 ÷ 10-3 mol/L). As the concentration increases, different changes were observed in the dyes UV-vis spectra indicating that the molecules are beginning to aggregate. The shapes of the obtained spectra were totally different as the position of the chloride was changed in the dye molecule. INTRODUCTION Direct dyes are generally large molecules, containing two or more azo groups, and sulfonic groups which provide solubility in water. They can adopt a planar structure, and tend to form dye-substrate intermolecular interactions that can facilitate aggregation under some experimental conditions [1]. It is important to understand dye aggregation in aqueous solution in order that the dyeing process will be successful. An important factor in the dyeing process is the fast diffusion of dye molecules into the fiber, a process which requires the disaggregation of the dye molecules. The aggregation of dyes presents a considerable interest and has been investigated by many researchers [2, 3]. The UV-Vis spectroscopy is the usually used method for investigation of the dye aggregation [4]. The dye aggregation is a function of temperature, electrolyte concentration, surfactant type, and dye concentration [5, 6]. In the present work, spectrophotometric analysis was used for the qualitative investigation of the aggregation of three direct dyes, as a function of chloride position in the dyes structure. MATERIALS and METHODS Three disazo direct dyes derived from 4,4'-diaminostilbene-2.2'disulphonic acid were investigated. The dye was purified by several recrystallizations from distilled water and characterized by thin layer chromatography, electronic spectra and mass spectroscopy. The visible spectra of the investigated dyes, in the concentration range between 5 x 10-6 to 3 x 10-3 mol/L were recorded in water. The samples were placed in an oven to sit over night. UV-visible absorption spectra were obtained using a CECIL CE 7200 spectrometer in the wavelength range 200 to 800 nm. The quartz cuvette of pathlengths 1, 0.5 cm, and 0.1 cm were used in such a manner that the absorbance values did not exceed 2. All measurements were carried out at 27 ± 2 oC.

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RESULTS The chemical structures of the investigated dye molecules are presented in Figure 1. HO

C C H H

N N

HNOC

N N

OH

SO3H HO3S

CONH

Cl

Cl

DASoCl HO

C C H H

N N

HNOC

N N

OH

SO3H HO3S

CONH

Cl

Cl

DASmCl HO Cl

C C H H

N N

HNOC

N N

OH

SO3H HO3S

Cl

CONH

DASpCl Figure 1. Molecular structure of the investigated dyes The obtained UV-visible absorption spectra's in aqueous solution are graphed together in Figure 2, plotted as ε = A/C.l. 0.25

DASoCl

DASmCl

0.30

0.20 0.25

-6

1*10 mol/L -6 5*10 mol/L -5 1*10 mol/L -5 5*10 mol/L -4 5*10 mol/L -3 1*10 mol/L -3 3*10 mol/L

0.10

-6

5*10 mol/L -5 1*10 mol/L -5 5*10 mol/L -4 1*10 mol/L -4 5*10 mol/L -3 1*10 mol/L

0.15

Abs

0.15

0.10

0.05 0.05

0.00 350

0.00 400

450

500

550

600

650

300

λ (nm) 0.4

400

λ (nm)

500

600

DASpCl

-6

5*10 mol/L -5 1*10 mol/L -5 5*10 mol/L -4 1*10 mol/L -4 5*10 mol/L -3 1*10 mol/L -3 3*10 mol/L

0.3

Abs

Abs

0.20

0.2

0.1

0.0 300

400

500

600

λ (nm)

Figure 2. The absorption spectra of DASoCl, DASmCl, and DASpCl dye, at different concentrations

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As can be seen in Figure 2, as the dye concentration increases, the maximum absorption wavelength shifted but the shape and the manners are very different. In case of DASoCl the maximum extinction coefficient decrease as the concentration increased. For the DASoCl dye the extinction coefficient decreased, and the maximum absorption wavelength of the principal peak shifts to lower wavelength till the concentration 5 x 10-4 mol/L and, at higher concentrations shifts to higher wavelength signifying that the molecules are beginning to aggregate. In case of DASmCl dye the extinction coefficient increase with increasing the dye concentration, although the maximum absorption wavelengths of the principal peak wavelength remain stable. As can be seen in Figure 2, for DASpCl dye, in concentration range 5 x 10-6 ÷ 1 x 10-4 mol/L and 5 x10-4 ÷ 3 x 10-3 mol/L, as the concentration increases, the extinction coefficient at 409.6 nm decreased. Between concentrations 1 x 10-4 ÷ 5 x 10-4 mol/L a major change was observed, when the shape of the spectra was changed, and an increase of the molar absorption coefficient was observed. For accuracy, the absorption coefficient at 416.8 nm was plotted as a function of concentration (Figure 3). 0.30

DASoCl

0.25

ε *10 (dm /mol)

0.18

2

2

ε *10 (dm /mol)

DASmCl

0.20

0.20

0.16

4

4

ε at 454.3 nm

0.14

0.15

ε at 414.4 nm

0.12

0.10 -6.0

-5.5

-5.0

-4.5

-4.0

-3.5

-3.0

-5.5

-2.5

-5.0

-4.5

logC0 (mol/L)

-4.0

-3.5

-3.0

logC0 (mol/L)

0.35

DASpCl

0.25

0.20

4

2

ε *10 (dm /mol)

0.30

0.15

0.10

ε at 410.8 nm

0.05 -5.0

-4.5

-4.0

-3.5

-3.0

-2.5

logC0 (mol/L)

Figure 3. Dependence of ε (at fixed wavelength) on the dye concentration From these graphs it is obvious that the absorption coefficient changes even at low concentration, signifying that molecules are beginning to aggregate, but the manner of changes is very different from dye to dye. By graphing the wavelength vs. concentration, for DASoCl dye a clear trend in the changes is noticed (Figure 4).

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DASoCl

Peak wavelength (nm)

450

440

430

420

principal peak wavelength 410 0.0000

0.0005

0.0010

0.0015

0.0020

0.0025

0.0030

C0 (mol/L)

Figure 4. Change in peak wavelength at different concentrations CONCLUSIONS • UV-Vis spectroscopy was used to study the effect of chloride position from the dye structure on the dye aggregation in aqueous solution. • From the absorption spectra graphs, it is easy to see that the spectra shifted as the chloride position was changed. • The nature of aggregation is dependent on the structure of each particular dye. LIST OF REFERENCES [1] Chao Y. C., Yang S. S. (1995). Disazo direct dyes derived from 4,4'-diamino derivatives of benzanilide, diphenylamine-2-sulfonic acid and stilbene-2,2'-disulfonic acid. Dyes and Pigments. 29, p.131-138. [2] Inglesby M.K., Zeronian S.H. (2002). Direct dyes as molecular sensors to characterize cellulose substrates, Cellulose. 2, p. 19-29. [3] Horowitz V.R., Janowitz L.A., Modic A.L., Heiney P.A., Collings P.J. (2005). Aggregation behavior and cromonic liquid crystal properties of an anionic monoazo dye, Physical Review E. 72, p. 041710-1- 041710-10. [4] Alarfaj N.A., El Khiate Z.M., Moussa E.A. (2008) Spectrophotometric studies on aggregation of some acid dyes in different media, JKAU: Sci. 20(1), p. 99-110. [5] Grindea M., Forst T., Hanganu A. (1983) Tehnologia vopsirii si imprimarii textilelor, Ed. Tehnica Bucuresti, p.80-86. [6] Stadler A., Renikuntla B.R., Yaron D., Fang A.S., Armitage B.A. (2010). Substituent effects on the assembly of helical cyanine dye aggregates in the minor groove of a DNA template, Langmuir. 27(4), p. 1472-1479.

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5-(4-PYRIDYL)DIPYRROMETHANEE-SILICA SOL SYNTHESIS AND LUMINESCENT PROPERTIES Zoltán Dudás1, Corina Enache1, Eugenia Făgădar-Cosma1, 1

Institute of Chemistry Timisoara of Romanian Academy, 24 Mihai Viteazul Ave., 300223, Timisoara, Romania

ABSTRACT Methodologies for the immobilization and characterization of 5(4-pyridyl)dipyrromethane into silica gel are described. The corresponding spectroscopic, thermal, and photochemical properties are used for their characterization and study. INTRODUCTION Nano-and micro-materials, based on pyrrole derivatives received great attention because of their optoelectronic properties, with extended applications from photosensing materials, catalysts, sensors for heavy metals [1], and biochemical agents [2] detection and recovery and gas sensors. In order to obtain new nanomaterials, various synthesis route of sol-gel methods are performed to improve dimension of pores, using different silica precursors mixtures, but also different types of organic compounds are used to be embeded in these hybrids. Based on our previously reported results [3, 4] Due to the great importance of sustainable chemistry in EU countryes, studies concerning the toxicity of these materials were also developed [5]. The aims of the initial study were to obtain hybrid porphyrin - materials with tailored dimension pores [6] and exhibiting intense red-absorption in Uv-vis and emmision spectra. The present experiment takes into consideration the use of an dipyrro compound for synthesis of porphyrins, namely 5(4-pyridyl)dipyrromethane (PPM), to see the fluorescence properties it introduced. 5(4-pyridyl)dipyrromethane, represent a valuable intermediate for the synthesis of asymmetrical trans A2B2 porphyrins, bearing pyridyl functional rings. The structure of 5(4pyridyl)dipyrromethane is represented on figure from the left. MATERIALS and METHODS Methyltriethoxysilane (MeTEOS) ≥ 98% from Fluka, Tetraetoxysilane (TEOS) ≥ 99% from Merk, Tetrametoxysilane (TMOS) 99% from Acros Organics, Tetrahydrofuran (THF) 99,8% and Sodium Fluoride 99% from Scharlau, Clorhidric Acid 37% from Silal Tradings. Apparatus 1H-NMR spectra were registered on a 400 MHz Bruker spectrometer, in DMSO. The chemical shifts are expressed in δ (ppm). A Bruker esquire HCT series mass spectrometer with Atmospheric Pressure Interface-ElectroSpray Ionization was used for registering MS. Thermal analysis experiments were carried on a Mettler-Toledo Intrument. Samples were heated from 25 to 800 °C in a 10 °Cmin−1 rate under air atmosphere. IR spectra (4000–400 cm-1) were collected on a JASCO 430 FT-IR spectrophotometer using pellets with samples dispersed in KBr. The photoemission and photoexcitation spectra were recorded with a Perkin Elmer LS55 luminescence spectrometer, by using a special holder for powdered solid samples. The luminescence spectra were recorded with constant slit widths, for excitation (2,5 nm) and for emission (5 nm). Excitation spectra were recorded by monitoring the red emission wavelength 656 nm, corresponding to maxima intensities. Emission spectra were obtained using 420 nm excitation wavelength corresponding to maximum emission intensity

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for each samples. In order to eliminate harmonic or scattering peaks a 505 nm cut-off filter to. Method for synthesis of 5(4-pyridyl)dipyrromethane named also as 4-(di-pyrrol-2-yl-methyl) pyridine was synthesized after previously reported literature data [7] by stirring for 12 h around 85°C a mixture of 4-pyridinecarboxaldehyde (1.9 mL, 20 mmol) and pyrrole (30 mL, 420 mmol). The product was evaporated to dryness, separated by column chromatography on alumina gel using hexane:ethyl acetate, 1:1. The yield was 42%. 5(4pyridyl)dipyrromethane: 1H-NMR (400 MHz, DMSO), δ (ppm): 10.58 (s, 2H, NH-pyrrole); 8.26 (m, 2H, 2,6-Pyridyl); 7.10(m, 2H, 3-5-Pyridyl); 6.60 (m, 2H, pyrrole); 5.93 (m, 2H, pyrrole); 5.68 (m, 2H, pyrrole); 5.29 (s, 1H); MS (ESI+): m/z=223.11 M]+· (C14H13N3]+· molecular ion. Method for sol-gel synthesis Two step acid catalysed hydrolysis of different type of precursors (TEOS, TMOS or MeTEOS in different molar ratios with TEOS), water, ethanol (EtOH) and 37% hydrochloric acid (HCl) with a silica precursor:H2O:EtOH:HCl of 1.0:3.7:2.9:1.2 × 10−4 mole ratios, were employed to prepare acid catalyzed silica precursors solution. After one hour of hydrolysis of the silca sprecursors, a solution consisting in PPM dissolved in THF, corresponding to 3.48 * 10-5 mole of PPM/ 1 mole silica precursors was added. Finally, for the second step of catalysis, 1.5 mmol of natrium fluoride was added The synthesis parameters and gelation time of samples are presented in table 1. Table 1. Synthesis parameters of samples and gelation time Sample Precursors Gelation time (min) 1 TEOS Instant 2 TMOS Instant 3 MeTEOS/TEOS 1:3 2 4 MeTEOS/TEOS 1:2 5 5 MeTEOS/TEOS 1:1 7 RESULTS The fluorescence emission spectra of all samples, present a maximum around 656 nm. Also, it can be observed a weak maximum, peaking around 720 nm. As can be noticed from Figures 1, the shape and positions of emission bands remain unchanged regardless the composition of sols. Instead, it could be observed changes in the emission intensities depending on the nature of silica precursors or mole ratio of precursors mixture. The highest emission intensity was obtained in the case of sample obtained from methyltriethoxysilane, as silica precursor. In the case of precursors mixture the better result was observed in the case of sample 5, synthesized from MeTEOS/TEOS in the 1:1 mole ratio.

Figure 1. Overlapped emission spectra of synthesized sol samples

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Figure 2 shows the IR spectra of samples 1 and 5 after drying at 105 °C. The peak at 460cm−1 is due to the deformation of Si–O–Si, bending modes of silicon dioxide. The signal centered at 800cm−1 is the typical peak of Si–O–Si vibrational mode and the 960cm−1 comes from the Si–OH stretching. Sample 5 shows a relatively weaker peak at 960cm−1 than sample 1, suggesting less hydroxylated silica existing in sample 5. The band at 1090–1200cm−1 was attributed to Si–O–Si skeletal vibration. The peak at 1630cm−1 should correspond to the vibration of water, where peak intensity of sample 1 is stronger than that of sample 5, showing the hydrophobic feature of sample 5. A broad band is observed at 3400–3500cm−1 due to the absorbed molecular water, where the difference in peak intensity for samples 1 and 5 is another indication of the more hydrophobic feature of sample 5 [8]. In conclusion the introduction of the methyl groups on the silica network offers a more hydrophobic profile to the silica xerogels.

Figure 2. Comparation of the FT-IR spectra of the sample 1 and 5 In figure 3 the TG/DTG/DTA curves of the dried sample 5 are presented. The TG curve of the xerogel shows a weight loss up to 150 °C which corresponds to a broad endothermic peak in the DTA curve, attributed to the physically adsorbed water on the silica surface and the evaporation of the volatile solvents [9]. In this range of temperature the main weight loss, of 17.03 wt% occurs. The total weight loss is corresponding to 23.24 wt%. In the 150-500 °C temperature range only a small weight loss is observed without any effect on the DTA curve. In the last temperature region the weight loss is accompanied by a sharp exothermic peak in the DTA curve at the same temperature is due to the oxidation of the methyl groups responsible for the xerogel hydrophobicity [10].

Figure 3. Thermal curves of the sample 5

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CONCLUSIONS " Novel nanocomposite with 5(4-pyridyl)dipyrromethane embedded silica gel has been synthesized by two step catalyzed sol-gel process . " Sol-gel immobilized PyPM nanocomposites photuluminescent properties were investigated in order to obtain high luminescent emission. " Al synthesized samples presented luminescent emission in red domain of spectra with maxima at 656 nm and 720 nm. The highest emission intensity was obtained in the case of sample synthesized from methyltriethoxysilane, as silica precursor. " Utilization of MeTEOS and TEOS precursor mixture better luminescent emission was observed in the case of sample prepared at MeTEOS/TEOS mole ratio of 1:1 " The thermal stability of the obtained xerogels was analyzed by thermal analysis and the silica network formation by the FT-IR spectroscopy. LIST OF REFERENCES [1] Vlascici D., Fagadar-Cosma E., Pica E. M., Cosma V., Bizerea O., Mihailescu G., Olenic L. (2008). Free Base Porphyrins as Ionophores for Heavy Metal Sensors Sensors. 8, p. 49955004. [2] Cristescu R., Popescu C., Popescu A.C., Mihailescu I.N, Ciucu A.A, Andronie A., Iordache S., Stamatin I., Fagadar-Cosma E., Chrisey D.B. (2010). Functional porphyrin thin films deposited by matrix assisted pulsed laser evaporation. Materials Science and Engineering B. 169, p. 106-110. [3] Enache C., Fagadar-Cosma E., Armeanu I., Dudas Z., Ianasi C., Vasile M., Dascalu D. (2010). Hybrid silica-metalloporphyrin nanomaterials exhibiting intensive absorption of light in the red-region. Digest Journal of Nanomaterials and Biostructures. 5(3). p. 683-689 [4] Fagadar-Cosma E., Enache C., Vlascici D., Fagadar-Cosma G., Vasile M., Bazylak G. (2009). Novel nanomaterials based on 5,10,15,20-tetrakis(3,4-dimethoxyphenyl)-21H,23Hporphyrin entrapped in silica matrices. Materials Research Bulletin. 44. p. 2186–2193. [5] Daniela Bratosin, Eugenia Fagadar-Cosma, Ana-Maria Gheorghe, Alexandrina Rugina, Aurel Ardelean, Jean Montreuil, Alexandru Gabriel Marinescu. (2011). In Vitro Toxi - and Ecotoxicological Assessment of Porphyrine Nanomaterials by Flow Cytometry Using Nucleated Erythrocytes. Carpathian Journal of Earth and Environmental Sciences 6(2). p. 225 – 234. [6] Dudas Z., Enache C., Fagadar-Cosma G., Armeanu I., Fagadar-Cosma E. (2010). Hybrid silica-porphyrin materials with tailored pore sizes. Materials Research Bulletin. 45. p. 1150– 1156. [7] Ruzie C., Michaud L., Boitrel B. (2002). Synthesis of the new bis-pyridyl crown capped porphyrin. Tetrahedron Letters. 43. p. 7423–7426. [8] Al-Oweini R., El-Rassy H. (2009). Synthesis and characterization by FTIR spectroscopy of silica aerogels prepared using several Si(OR)4 and R''Si(OR')3 precursors. Journal of Molecular Structure. 919. p. 140–145. [9] Brambilla R., dos Santos J.H.Z., Miranda M.S.L., Frost R.L. (2008). Thermal stability of octadecylsilane hybrid silicas prepared by grafting and sol–gel methods. Thermochimica Acta. 469. p. 91–97. [10] Bhagat S.D., Oh C.S., Kim Y.H., Ahn Y.S., Yeo J.G. (2007). Methyltrimethoxysilane based monolithic silica aerogels via ambient pressure drying. Microporous and Mesoporous Materials. 100. p. 350–355.

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INFLUENCE OF SYNTHESIS PARAMETERS ON LUMINESCENCE EMISSION PROPERTIES OF SOME SOL-GEL DERIVED Eu3+ DOPED WILLEMITE PHOSPHORS Corina Enache1, Zoltán Dudás1, Daniela Dascălu2 1

Institute of Chemistry Timisoara of Romanian Academy, 24 Mihai Viteazul Ave., 300223, Timisoara, Romania, e-mail: corinaen2003@yahoo.co.uk 2 West University of Timisoara, Faculty of Chemistry, Biology, Geography, 16 Pestalozzi Street, 300115 - Timisoara, Romania.

ABSTRACT Europium doped zinc silicate phosphor sample, corresponding to general formula, Zn2-(x+y)EuxLiySiO4, (where x = 0.01 or 0.02 and y = 0, 0.01, or 0, 02), have been synthesized by acid, or two steps (acid-base) catalyzed sol-gel processing, in the presence, or absence of Li+ ions, as charge compensator. The obtained xerogel samples was successively annealed, at different steps, up to 1000°C, for 180 minutes time soaking for each temperature. Starting from 700°C temperature, the formation of Si-O-Zn linkage was put in evidence by FT-IR spectra. The appearance of IR signals corresponding to willemite vibration modes has been observed for 900ºC calcined samples. At UV excitation beam, the luminescence spectra of Zn2SiO4:Eu3+ synthesized phosphors samples show some emission peaks in the red region of spectra, assigned to 5D0→7Fj (j = 0, 1, 2, 3, 4 and 5) spin forbidden f–f transitions of Eu3+ ions, respectively. Specifically they were situated around 575 nm, 590 nm, 615 nm, 624 nm, 650 nm and 700 nm. The most intense emission was observed for the 1000°C calcined sample, with 0.02 moles Eu3+ activator content, prepared with charge compensator. INTRODUCTION Among inorganic phosphors, willemite (α-Zn2SiO4), with phenacite structure, is a very suitable host for both rare earths (RE) and transition metals activators [1]. Mn-activated willemite (Zn2SiO4:Mn) is an efficient green phosphor which it has been widely used as a green component in cathode ray tubes, in fluorescent lamps and electroluminescent devices [2–3]. More recently, rare earth doped Zn2SiO4 phosphors have been attracted great attention for their luminescence properties and possible applications in flat panel display devices [3-5]. The sol–gel technology offers several processing advantages over the conventional method, including lower temperature process, better homogeneity, and higher emission efficiency of the powder phosphors [1, 2]. In this paper are presented the synthesis studies by thermal analysis, FT-IR and luminescence spectroscopy of some europium doped willemite phosphors, obtained by sol-gel processing. MATERIALS and METHODS The powdered europium doped zinc silicate phosphor samples, corresponding to general formula, Zn2-(x+y)EuxLiySiO4, (where x = 0.01 or 0.02 and y = 0, 0.01 or 0.02 moles), have been synthesized by one step (acid) or two steps (acid-base) catalyzed alcoxy sol-gel method. For some samples, Li+ ions were used as charge compensator. Tetraethyl orthosilicate (TEOS, 99%, Fluka), absolute ethanol (EtOH, Chimopar) zinc nitrate hexahydrate (Merck, extra pure), europium (III) chloride hexahydrate (EuCl3·6H2O, 99.9% Fluka, p.a.), lithium nitrate trihydrate 99%, Merck, p.a), distilled water, catalyst-hydrochloric acid (37%, Silal Trading,

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p.a.) and ammonia solution (25%, Silal Trading) were used as starting materials. The EtOH/TEOS and HCl/TEOS mole ratios of 15/1 and 0.02/1 it was employed, respectively. The synthesis conditions are presented in table 1. Table 1. The synthesis parameters of samples and gelation time Sample Europium content (x) Lithium content (y) NH3 Gelation time [mole] [mole] [mole] 1 0.01 74 days 20 hours 2 0.01 0.00938 Instant 3 0.02 22 days 18 hours 4 0.02 0.010275 Instant 5 0.01 0.01 24 days 22 hours 6 0.01 0.01 0.07501 Instant 7 0.02 0.02 65 days 8 0.02 0.02 0.08308 Instant The samples were prepared as follows: a mixture of calculated amounts of Zn(NO3)2·6H2O, EuCl3·6H2O, LiNO3·3H2O, EtOH, HCl, and H2O was added by slow dropping under vigorous stirring to a calculated amount of solution of TEOS, precursor dissolved into absolute EtOH. For two steps catalyzed samples, after the acid step, a 2.5% NH3 solution was slowly dropped, until achieving the gelation point. After gelation, samples ware successively dried at 45°C, 60°C and 105°C, for 10 hours, at each temperature. Further successively thermal treatments were performed at 300°C, 500°C, 700°C, 900°C and 1000°C, for 3 hours soaking time. Thermal analysis was performed with a Mettler-Toledo unit, in air atmosphere from 25°C to 1000°C with a heating rate of 10°C min-1. FT-IR (JASCO 430 FT-IR, KBr pellets) spectra were carried out, in the 4000-400 cm-1 range. The photoemission and photoexcitation spectra were recorded with a Perkin Elmer LS55 luminescence spectrometer, by using a special holder for powdered solid samples. The luminescence spectra were recorded with constant slit widths, for excitation (5 nm) and for emission (4.5 nm). Excitation spectra were recorded by monitoring the red emission wavelength of 615 nm. Emission spectra were obtained using an excitation wavelength corresponding to maximum emission intensity for each sample. In order to eliminate harmonic or scattering peaks a 515 nm cut-off filter was used. RESULTS and DISCUSSION In Figure 1 are presented the thermal analysis results of xerogel sample labeled as 8. In the range 60-500ºC, the DTA curve, shows some endothermic effects, which was ascribed to water evaporation, zinc nitrate dissolution in crystallization water, and residual solvent removal, respectively. Basic zinc nitrates formation, pyrolysis, and organic groups combustion, superimposed effects, can also occur in this temperature range. The exothermic effect, which appears between 680-830ºC, was attributed to willemite crystalline network development [2, 6, 7]. The observed global weight – loss amount, from the TG curve, in the temperature range of 25-1000ºC, was: 41.47%. No significant weight loss occurred above 800ºC. However, DTA curves did not present a well-defined exothermic peak, indicating that crystallization occurred slowly in the samples [2]. In figure 2 are presented the overlapped FT-IR spectra of sample labeled as 8, calcined at different temperatures. In the range 350-750 cm-1, FT-IR spectrum of xerogel sample 8, (curve (1)) presents a broad band corresponding to Zn-O vibrations and Si-O-Si bending modes [6, 7]; ~800 cm-1 feature is due to symmetric Si–O–Si stretching vibration modes [6] ~830 cm-1, 1385 cm-1 and 1355 cm-1 peaks correspond to NO3- ions [8]; 1090 cm-1 band is

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assigned to TO mode of Si-O–Si asymmetric stretching vibration; 960 cm-1 signal was attributed to Si–OH and Si–O–H stretching of silanol terminal groups; ~1090 cm-1 peak with a shoulder centred around 1200 cm-1 is attributed to the LO mode of the Si-O-Si asymmetric stretching vibration [6].

Figure 1. Thermal curves of xerogel sample labeled as 8, dried at 105°C

Figure 2. FT-IR spectra of 8 numbered sample, calcined at (1)-105°C, (2)-300°C, (3)-500°C, (4)700°C, (5)-900°C and (6)-1000°C At increased firing temperatures of the samples, the specific IR features of NO3-, OH-, H2O and silanol, and other organics groups, are gradually diminishing to disappearance. The peak width ranging in the 1000-1100 cm-1 decreases, and the peak position shifts towards lower wave numbers, reflecting general trends to the depolimerization of silicate network [9]. The Si-O-Zn linkage can be observed by the shift of the Si-O stretching from 1096 cm-1 to 940 cm-1, and the shift of the Zn-O stretching vibration modes from 505 cm-1 and 455 cm-1 to 548 cm-1. Consequently, from the spectra of samples fired at 900ºC and 1000ºC it can be observed the IR bonds signals corresponding to willemite: 872 cm-1 (ν1, SiO4), 978, 934 and 905 cm-1 (ν3, SiO4), 462, 396 and 380 cm-1 (ν4, SiO4), 580 cm-1 (ν1, ZnO4) and 617 and 600 cm-1 (ν3, ZnO4) [10].

Figure 3. Excitation and emission spectra of Figure 4. Excitation and emission spectra of samples 1-4, calcined at 1000ºC samples 5-8, calcined at 1000ºC In the Figures 3 and 4 are presented the emission and excitation spectra of obtained samples, thermally treated at 1000°C. By UV excitation, the luminescence spectra of Zn2SiO4:Eu3+ synthesized phosphors samples show some emission peaks in the red region of spectra. The emission maxima were situated around 575, 590, 615, 624, 650 and 700 nm, this being assigned to 5D0→7Fj (j= 0, 1, 2, 3, 4 and 5) spin forbidden f–f transitions of Eu3+ ions, respectively [1, 4, 5]. Comparing the activator content, better results were obtained for the samples with 0.02 moles Eu3+. The emission maxima were higher in the case of samples

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prepared with charge compensator. The most intense emission was observed for the 1000°C calcined sample, with 0.02 moles Eu3+ activator content, prepared with charge compensator. CONCLUSIONS ¾ By sol-gel processing europium activated willemite phosphor powders, with red emission, have been obtained. ¾ Thermal treatment influence, upon the formation of willemite, has been studied by thermal analysis and FT-IR spectroscopy techniques. ¾ Starting from 700ºC, the formation of α-willemite was put in evidence by Si-O-Zn linkage. The results are confirmed by exothermic effect attributed to the crystalline network formation of Zn2SiO4, revealed by DTA curve, starting from 680ºC. The arising IR features corresponding to willemite vibration modes, have been observed starting from 900ºC. ¾ The luminescence spectra of Zn2SiO4: Eu3+ phosphors samples show some emission peaks in the red region at around 575, 590, 615, 624, 650 and 700 nm. Comparing the emission intensities it can be seen that they are higher for all samples prepared with charge compensator. Taking into account the influence of activator content the better results were obtained in case of samples prepared with 0.02 moles Eu3+. ¾ Overall, the best result, meaning the highest luminescence intensity it was obtained for 1000°C calcined sample, with 0.02 moles Eu3+ activator content, containing 0.02 moles K+, as charge compensator ACKNOWLEDGEMENTS The authors thank to Romanian Academy. LIST OF REFERENCES [1] Krsmanovic R., Antic Z., Zekovic I., Dramicanin M.D. Polymer-assisted sol–gel synthesis and characterization of Zn2SiO4: Eu3+ powders. (2009). Journal of Alloys and Compounds. 480, p. 494-498. [2] Tsai M. T., Lu Y.F., Wang Y.K. (2010). Synthesis and characterization of manganesedoped zinc orthosilicate phosphor powders. Journal of Alloys and Compounds. 505, p. 818–823. [3] Zhang Q.Y., Pita K., Ye W., Que W.X. (2002). Influence of annealing atmosphere and temperature on photoluminescence of Tb3+ or Eu3+-activated zinc silicate thin film phosphors via sol–gel method. Chemical Physics Letters. 351, p. 163–170. [4] Patra A., Baker G. A., Baker S. N. Synthesis and luminescence study of Eu3+ in Zn2SiO4 nanocrystals. (2004). Optical Materials. 27, p. 15–20. [5] Joly A.G., Chen W., Zhang J., Wang S. (2007). Electronic energy relaxation and luminescence decay dynamics of Eu3+ in Zn2SiO4:Eu3+ phosphors. Journal of Lumininescence.126, p. 491–496. [6] Brinker C. J., Scherer G. W. (1990). Sol-Gel Science. Academic Press, Inc., New York. [7] Zhang Q.Y., Pita K., Kam C.H. (2003). Sol–gel derived zinc silicate phosphor films for fullcolor display applications. Journal of Physics and Chemistry of Solids. 64, p. 333–338. [8] Hester R.E., Scaife C.W.J. (1967). Vibrational Spectra of Molten Salts. III. Infrared and Raman Spectra of Variably Hydrated Zinc Nitrate, The Journal of Chemical Physics. 47, p. 5253-5258. [9] Maliavski N., Dushkin O.V., Scarinci G. (2001). Low-temperature synthesis of some orthosilicates, Ceramics-Silikaty. 45, p. 48-54. [10] Lin C.C., Shen P. (1994). Sol-gel synthesis of zinc orthosilicate, Journal of NonCrystalline Solids. 171, p. 281-289.

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SYNTHESIS AND LUMINESCENCE PROPERTIES OF SOME Ce3+ DOPED SILICA SOLS Corina Enache1, Zoltán Dudás1, Cecilia Savii1 Institute of Chemistry Timisoara of Romanian Academy, 24 Mihai Viteazul Ave., 300223, Timisoara, Romania, e-mail:corinaen2003@yahoo.co.uk ABSTRACT Ce3+-doped silica sols samples were prepared by acid, or two steps catalyzed sol-gel process, at different concentration of Ce3+ dopant. As silica precursors, tetraetoxysilane, or tetrametoxysilane, or a precursors mixture consisting of tetraetoxysilane and isobuthyltrietoxysilane, were used. By UV excitation, all synthesized samples presented strong luminescence emission with maxima situated at ~ 386 nm. Regarding the emission efficiency, better results were achieved at lower Ce3+ concentrations. Depending on precursors nature, a favorable influence had the use of precursors mixture. INTRODUCTION Research into lanthanide-doped organic–inorganic hybrid materials resulted in the development of high efficiency and stable materials for optics [1]. The incorporation of cerium, as dopant in silicate glasses, has been widely studied for applications as phosphors, scintillators, detectors, UV absorbers, emitters and activators due to its luminescence properties [2]. While the usual method of preparation of such glasses is conventional melting, the sol-gel processing technique has also been used to prepare them [2, 3]. In Ce doped glasses, cerium can be present as Ce4+, or Ce3+ ions, depending on preparation conditions, and this aspect is related to distinct optical properties [4]. It was reported two main luminescent bands of Ce3+ ions at 357 and 450 nm in the samples of Ce3+-doped glasses and crystals. Both of the two bands were attributed to the 4f–5d transitions of Ce3+ ions. But, depending on relationship between the luminescence bands and the environment structure, in some Ce3+doped materials, there was only one luminescence band [5]. In this work, the influences of cerium concentration, nature of the silica precursors and type of catalysis on the luminescence properties of Ce-doped silica sols samples, obtained by sol-gel technique, have been investigated. MATERIALS and METHODS The Ce3+ ions doped silica sols were synthesized by sol-gel process, starting from: tetraetoxysilane (TEOS ≥ 99%, Merck), tetrametoxysilane (TMOS ≥ 99%, Acros Organics) isobuthyltrietoxysilane (iBT, ≥98, Fluka), absolute ethanol (EtOH, p.a., Chimopar), cerium (III) chloride heptahydrate (CeCl3⋅7H2O, ≥ 98%, Fluka), distilled water, catalyst – hydrochloric acid (HCl, 37%, p.a., Silal Trading) and sodium fluoride (NaF, 99%, Scharlau). The H2O/silica precursors, EtOH/silica precursors, HCl/silica precursors, NaF/silica precursors used mole ratio were in all cases, 6/1, 8/1, 0.01/1, and 0.02/1 respectively. Synthesis scheme are presented in Figure 1. In the Table 1 the synthesis parameters of samples are presented.

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Table 1. Synthesis parameters of samples Sample

Silica precursor

Catalyst

0 0-b 1 1-b 2 2-b 3 3-b 4 4-b 5 5-b 6 6-b 7 7-b 8 8-b 9 9-b 10 10-b 11 11-b 12 12-b 13 13-b

TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TEOS TMOS TMOS TMOS TMOS TMOS TMOS TMOS TMOS TEOS/iBT (1/1 mole ratio) TEOS/iBT (1/1 mole ratio)

HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF HCl HCl, NaF

Ce/silica precursor mole ratio 0 0 0.01 0.01 0.02 0.02 0.04 0.04 0.08 0.08 0.1 0.1 0.14 0.14 0.18 0.18 0.2 0.2 0 0 0.01 0.01 0.02 0.02 0.04 0.04 0.01 0.01

Observation

Instant gelation

Instant gelation

The photoemission and photoexcitation spectra were recorded with the help of a Perkin Elmer LS55 luminescence spectrometer. The luminescence spectra were recorded at a 100 nm/min, with constant slit widths, for excitation (15 nm) and for emission (2.5 nm). Excitation spectra were recorded by monitoring the blue emission wavelength at 386 nm, corresponding to maxima intensities. Emission spectra were obtained by using an UV excitation wavelength corresponding to maximum emission intensity for each sample. A 390 nm cut-off filter to eliminate harmonic or scattering peaks was used.

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Figure 1. Synthesis flow chart for obtaining Ce3+ doped silica sols

RESULTS The luminescence spectra of obtained Ce doped silica sol samples are presented in Figures 26

Figure 2. Excitation and emission spectra of Figure 3. Excitation and emission spectra of samples 0, 1, 1-b, 2 and 2-b samples 3, 3-b,4, 4-b, 5 and 5-b

Figure 4. Excitation and emission spectra of Figure 5. Excitation and emission spectra of samples 6, 6-b,7, 7-b, 8 and 8-b samples 9, 10, 10-b,11 and11-b

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From Figs. 2-6, it can be seen that all the samples present luminescent emission with maxima situated at around 386 nm. Taking into account the concentration of cerium ions dopant, the higher intensities were obtained for Ce/silica precursor mole ratio of 0.01/1. At higher dopant concentration, the emission intensities were reduced. This result could be related to emission quenching effects, arising from the high Ce concentration [5] Figure 6. Excitation and emission spectra of Depending on precursors nature, the most intense emission were obtained for the samples obtained samples 12, 12-b,13 and13-b from the mixture of TEOS-iBT precursors.

The width, shape and maxima position of the excitation spectra were influenced by cerium concentration and catalysis type. The dopant content increasing has led to a bathochromic shift of excitation maxima. CONCLUSIONS ¾ Starting from different dopant concentrations and silica precursors, Ce3+ silica sols samples were obtained by acid, or two steps catalyzed sol-gel process. ¾ Strong luminescence emissions with maxima situated at around 386 nm, were obtained by UV excitation. ¾ Luminescence emission efficiency was influenced by both doping concentration and the nature of the precursors ¾ The best results were obtained in the case of samples with low dopant content, synthesized from a mixture of tetraetoxysilane and isobuthyltrietoxysilane . ¾ The shape and the position of the maxima, corresponding to the excitation bands, were determined by dopant concentration and catalysis type. LIST OF REFERENCES [1] Escribano P., Julian-Lopez B. Planelles-Arago J., Cordoncillo E., Viana B., Sanchez C. (2008). Photonic and nanobiophotonic properties of luminescent lanthanide-doped hybrid organic– inorganic materials, Journal of Materials Chemistry. 18, p. 23-40. [2] Rosero-Navarro N. C., Figiel P., Jedrzejewski R., Biedunkiewicz A., Castro Y., Aparicio M., Pellice S. A., Duran A. (2010). Influence of cerium concentration on the structure and properties of silica-methacrylate sol–gel coatings. Journal of Sol-Gel Science and Technology. 54, p. 301-311. [3] Patra A., Kundu D., Ganguli D. (1997). Spectroscopic Study of Cerium-Doped Silica Gel Monoliths and Their Densified Derivatives. Journal of Sol-Gel Science and Technology 9, p. 6569. [4] Agnello S., Iovino G., Buscarino G., Boscaino R., Costa F. (2011). Effects of thermal treatments in controlled atmosphere on the Ce oxidation state in Ce–Ti-Eu doped SiO2 sol–gel glasses. Journal of Sol-Gel Science and Technology. 58, p. 56-61. [5] Xu G.Q., Zheng Z.X., Tang W.M., Wu Y.C. (2007). Spectroscopic properties of Ce3+ doped silica annealed at different temperatures. Journal of Luminescence. 124, p. 151-156.

ACKNOWLEDGEMENTS: The authors thank to Romanian Academy.

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UNSATURATED PHOSPHONIC ACID, A NOVEL PRECURSOR TO FABRICATE METAL ORGANIC FRAMEWORKS Aurelia Visa, Bianca Maranescu, Adriana Popa, Gheorghe Ilia Institute of Chemistry Timisoara of the Romanian Academy, 24 Mihai Viteazul Ave, RO-300223, Timisoara, Romania, e-mail: apascariu@yahoo.com ABSTRACT Investigations on phosphonates metal organic frameworks (MOFs) have attracted interest during the last two decades due to their captivating network topology, structural flexibility and multiple special properties. The synthesis of 1-phenylphosphonium acid, as precursor of metal organic framework was described. The synthesized compound was analyzed by 1H and 31 P-NMR, HPLC, MS, TG and IR spectroscopy. The PM3 semi-empirical analysis of precursor was made in order to establish their design, structural properties, thermodynamic and electronic properties. INTRODUCTION The chemistry of organophosphorus compounds was rapidly developed due to the multiple properties that can potentially act. Most of metal organic frameworks exhibit a variety of open framework architectures.1,2 These compounds received extensive research attention in recent years due to their applications in the areas of gas storage,3 heterogeneous catalysis,4 separation,5 ion exchange,6 magnetism,7 sensors,8 etc. An outstanding class of metalphosphonates is the one that use a phosphonic derivative containing a double bond. Conant9 describe the synthesis of 1-phenylphosphonic acid PVP in two ways: from acetophenone, phosphorus trichloride and acetic acid or acetophenone, phosphorus trichloride and water at 150oC. High temperature is needed to remove unreacted acetophenone. Chosen method using an excess of acetophenone, to serve as reactant, is advantageous in practical terms. After mixing with phosphorous trichloride with acetophenone, preferably at room temperature, water is added in drops to maintain the reaction mixture between 5-200C. The reaction mixture contains acid, product and unreacted acetophenone. The acetophenone removal is done by driving under vacuum at temperatures below 100°C.

H2C=C(C6H5)-P(O)(OH)2 + 3 HCl

CH3-CO-C6H5 + PCl3 + 2 H2O

Acid is separated from the reaction mixture by recrystallization from hydrochloric acid. MATERIALS and METHODS Analysis methods PVP acid was characterized by physicochemical methods: mass spectroscopy, NMR spectroscopy, IR spectroscopy, UV-VIS spectroscopy, high performance liquid chromatography (HPLC), thermogravimetric analysis (TG). Materials For synthesis were used acetophenone (Aldrich), phosphorus trichloride (Aldrich), without other purification and distilled water.

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Quantum chemical method Gas phase equilibrium geometry of conformers was obtained by semi-empirical PM3-RHF calculations using the Polak-Ribiere conjugate gradient algorithm for geometry optimization10. Stop criteria were: SCF convergence of 10-5 and RMS gradient of 10-2 kcal/A·mol. Calculations have been performed with HyperChem7.52 package11. Experimental method: Into a 500 ml reaction flask filled with nitrogen 2.75 moles acetophenone and 1.82 moles of PCl3 were placed and stirred at room temperature for one hour. To the reaction mixture was added dropwise 3.64 moles of distilled water. The reaction temperatures was adjusted with ice at 5oC to the beginning of the water addition and increased at 50oC when the addition was completed. The total water addition time was 45 minutes. The reaction mixture contains product, hydrochloric acid and unreacted acetophenone. The HCl was trapped in a caustic scrubber. The acetophenone removal is done by driving under high vacuum at temperature below 100°C. The PVP crystals were filtered and washed with HCl 37%. RESULTS

The PVP acid was charactherized by mass spectroscopy (MS), NMR spectroscopy, IR spectroscopy, UV-VIS spectroscopy, high performance liquid chromatography (HPLC) and thermogravimetric analysis (TG). The MS spectra was recorded with an Bruker Daltonik Esquire 6000, equipped with ESI (Electrospray ionization). From MS spectra was noticed that the molecular pick was found at m/z=182. The HPLC system used in this work was a Jasco PU-1580 solvent delivery system and a MD1510 UV/VIS detector, with a 10 μl flow cell. A reversed-phase Nucleosil C18 column (25 cmx0,4mm, μparticle size) was used for separation. A Reodyne 7725 injector with a 10 μl external loop was used for sample introduction. A Borwin Chromatography workstation was used to control the operation of HPLC, obtain the chromatogram, and perform data calculation. In HPLC appear a single signal, this proves that the analyzed sample contains a single compound with tr=3.180 min. The 1H, 31P NMR spectra were recorded with a Bruker DRX 400 MHz spectrometer in CDCl3. In Figure 1 is shown the 1D-NMR spectra.

b a 1 31 Figura 1. H-NMR (a) and P-NMR (b) spectra of PVP

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From NMR spectra the following data were collected: 1H-NMR (400MHz, CDCl3): δ: 2.15 (s, P-OH) 6,51 (t, 3JHH = 12,3 Hz, 3JHP = 29,8Hz, =CH), 6.70-7.90 (m,C6H5-); 31P-RMN (162MHz, CDCl3):δ: 18.20 ppm, s. From UV-VIS spectra recorded in methanol with a CECIL CE 720 result a maximum absorbtion at λ=240 nm due to π-π∗ interactions. The infra-red spectrum of PVP recorded as a KBr pellet with Jasco-FT/IR-4200, contains a broad band at 2500-3700 cm-1 corresponding to P-OH group, at 1698 cm-1 corresponding to C=C group, at 1202 cm-1 appear the bands corresponding to aromatic moiety. The spectrum also contains two intense bands at 1070 and 964 cm-1 correspond to –PO3 stretching modes and two weaker bands at 777 and 702 cm-1 belonging to the monosubstituted vinyl moiety. A thermal gravimetric analysis was also performed on crystals of PVP and indicated a weight loss around 100ºC corresponding to water traces and to the melting of PVP acid. At 520.2 °C which correspond to loss of the vinyl portion of the phosphonate, respectively. The bond lengths and the heat of formations energies are presented in Figure 2 and the HOMO-LUMO orbitals are presented in Figure 3.

1-phenylvinylphosphonic acid Heat of Formation (ΔHf) =-149.644 kcal/mol

2-phenylvinylphosphonic acid Heat of Formation (ΔHf) =-157.937 kcal/mol Figure 2. Bond lengths and heat of formations for phenylvinylphosphonic acid

HOMO-1 HOMO

LUMO LUMO+1

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Figure 3. The HOMO,LUMO orbitals of PVP CONCLUSIONS ƒ From the reaction of acetophenone, phosphorus trichloride and distilled water was obtained 1-phenylvinylphosphonic acid. ƒ The obtained compound was completely analyzed by mass spectroscopy, NMR, IR spectroscopy, UV-VIS spectroscopy, high performance liquid chromatography and thermogravimetric analysis. ƒ By PM3 semi-empirical calculations were extracted informations regarding the design, structural properties, thermodynamic and electronic properties. Acknowledgments: The authors thank to the National Councilor for Research and High Education (CNCSIS) for allowing the financial backgrounds usefor purchasing the HyperChem 7.52 package by CNCSIS grant nr.776/2005/Agrement 27658/2005/GR177/2006/1973/2006. Research was partially supported by Program no 2, Project no. 2.4 from Institute of Chemistry Timisoara of Romanian Academy. LIST OF REFERENCES

1. Cheetham A.K., Rao C.N., Feller K. (2006). Structural diversity and chemical trends in hybrid inorganic–organic framework materials. Chem. Commun., 46, 4780-4795 2. Kitagawa S., Uemura, K. (2005). Dynamic porous properties of coordination polymers inspired by hydrogen bonds, Chem. Soc. Rev., 34, 109-119 3. Ma S., Sun D., Simmons J.M., Collier C.D., Yuan D., Zhou H.C. (2008). Metal-organic framework from an anthracene derivative containing nanoscopic cages exhibiting high methane uptake, J. Am. Chem. Soc., 130, 1012-1016 4. Seo J.S., Whang D., Lee H., Jun S.I., Oh J., Jeon Y.J., Kim K. (2000). A homochiral metal– organic porous material for enantioselective separation and catalysis, Nature, 404, 982-986 5. Li G., Yu W. Cui Y. (2008). A Homochiral nanotubular crystalline framework of metallamacrocycles for enantioselective recognition and separation. J. Am. Chem. Soc., 130, 4582-4583. 6. Tzeng B.C., Chiu T.H., Chen B.S., Lee G.H. (2008). Novel single-crystal-to-single-crystal anion exchange and self-sssembly of luminescent d10 metal (CdII, ZnII and CuI) complexes containing C3-symmetrical ligands. Chem. Eur. J. 14, 5237-5245. 7. Yao H.C., Li Y.Z., Gao S., Song Y., Zheng, L.M. Xin X.Q. (2004). Copper phosphonates with dinuclear and layer structures: a structural and magnetic study. J. Solid State Chem., 177, 4557-4563 8. Alberti G., Cherubini F., Palombari R. (1995). Potentiometric and amperometric gas sensors based on the protonic conduction of layered zirconium phosphates and phosphonates. Sensors Actuators B: Chem., 24, 270-272 9. Conant J.B., Coyne B.B. (1922) Addition reactions of the phosphorus halides. V. The formation of an unsaturated phosphonic acid. J. Am. Chem. Soc. 44, 2530-2536 10. Levine I.N. (2000) ”Quantum chemistry”, 5th Edition, Prentice Hall, Inc., Upper Saddle River, New Jersy 07458, Chap. 15, Chap. 17 11. *** HyperChemTM, Release 7.52 for Windows, Copyright (2003), Hypercube, Inc, 1115 NW 4th Street, Gainesville, FL 32601, US

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SYNTHESIS AND CHARACTERIZATION OF A NEW METAL ORGANIC FRAMEWORK Bianca Maranescua, Aurelia Vişaa, Smaranda Iliescua, Gheorghe Iliaa, Zeno Simona a

Institute of Chemistry Timişoara of the Romanian Academy, 24 M. Viteazul Ave, Timişoara - 300223, Romania

ABSTRACT The synthesis of a new metal-phosphonate is described in this paper. Mg2+ vinylphosphonate has been synthesized by using an equimolecular ratio of reagents in hydrothermal conditions. The compound has been characterized by X-Ray and IR spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetry (TG) and quantum chemical calculations. Last method have been used to establish supramolecular pores size and to predict synthesized compound ability to filter hydrogen, methane, carbon dioxide, carbon monoxide, sulphur dioxide and benzene gases. INTRODUCTION Most recent technologies require materials with combined properties, which are not offered by conventional materials. Metal organic frameworks (MOFs) are one of most important synthetic material class because their wide variety of chemical compositions with improved or unusual properties are useful in fields like optics, electronics, mechanics, biology and medicine. Typical applications are smart membranes, new generations of photovoltaic cells, fuel cells, photocatalysts, temperature and humidity resistive sensors and smart microelectronic components [1-3]. Introduction of the organic group into the structure by using phosphorus compounds can be done in various ways, depending on the desired material [4,5]. Metal-phosphonate complexes are MOFs resulted from phosphonic acids reaction with metal salts in hydrothermal conditions. Metal-phosphonates are characterized by organic part being liked to inorganic part into a regular repetitive structure, into a crystalline network [6-8]. MOFs structures are suitable for gas adsorption and storage, competing with other microporous materials such as polymers, zeolites or carbon materials, all presenting channels and pores in the size range of 2.5 to 20Å [9]. MATERIALS and METHODS A 100 mL round-bottomed flask was charged with Mg(NO3)2⋅6H2O (50.0 mmol), vinylphosphonic acid (50.0 mmol), urea (50.0 mmol), and distilled water (50 mL). The pH was adjusted to 2.8-3.1 with an aqueous solution of NaOH (0.10 M).The solution was heated in an oil-bath at 65-800C for 75-80 hours. The resulting crystals were collected by filtration and dried in air (yield: 70%). White solid Mg2+ vinylphosphonate compound has been obtained.

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RESULTS The synthesized compound has been characterized by X-Ray and IR spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetry (TG) and quantum chemical calculations. X-Ray powder diffractogram has been performed by using BRUKER D8 Advance diffractometer at characteristic radiation Kα of copper, with generator mode 40 kV x 30 mA, and into the secondary beam path having inserted a graphite monochromator for copper characteristic radiation. Goniometer geometry was Bragg–Brentano (θ/2θ) with divergent incident beam. For the primary beam it have been used a Soller slit and a vertical rectangular diaphragm, and for the secondary (diffracted) beam two vertical slits. The elementary cell was found to be orthorhombic, and the reticular parameter a representing the distance between crystalline layers of the structure vary by vinyl group nature. Vinylic groups are oriented into interlamellar space, and weak Van der Waals forces keep the layers linked (Figure 1). Magnesium ions are hexacoordinated, and arranged into a distorted tetragonal bipyramid with O-Co-O angles between 58o and 100o [8]. 3 4 0 0 0 3 3 0 0 0 3 2 0 0 0 3 1 0 0 0 3 0 0 0 0 2 9 0 0 0 2 8 0 0 0 2 7 0 0 0 2 6 0 0 0 2 5 0 0 0 2 4 0 0 0 2 3 0 0 0 2 2 0 0 0 2 1 0 0 0

Lin (Counts)

2 0 0 0 0 1 9 0 0 0 1 8 0 0 0 1 7 0 0 0 1 6 0 0 0 1 5 0 0 0 1 4 0 0 0 1 3 0 0 0 1 2 0 0 0 1 1 0 0 0 1 0 0 0 0 9 0 0 0 8 0 0 0 7 0 0 0 6 0 0 0 5 0 0 0 4 0 0 0 3 0 0 0 2 0 0 0 1 0 0 0 0 6

1 0

2 0

3 0

4 0

2 - T h e ta F il e : M V 7 - M g - s c o c h - 4 0 k V - 4 0 m A - p a s 0 _ 0 5 - 0 _ 6 - 0 _ 2 - 1 s e c . r a w O p e r a ti o n s : I m p o r t

5 0

6 0

7

- S c a le

- T y p e : 2 T h /T h l o c k e d - S t a r t : 2 . 0 0 0

° - E nd : 7 0 .00 0

° - S te p : 0 .0 5 0

° - S te p t i m e : 1 . s - T

Figure 1. X-Ray powder diffractogram for Mg2+ vinylphosphonate IR recorded spectra of Mg2+ vinylphosphonate by using Jasco-FT/IR-4200 reveals two intense absorption bands at 1110 and 1001 cm-1 attributed to -PO3 and one weak band at 756 cm-1 corresponding to monosubstituded vinyl group. A strong absorption is observed around the 3495 cm-1 corresponding to hydroxilyc group. The absence of any band in 2700-2560 cm-1, range where P-O and P-OH groups absorption should appear, confirm the Mg2+ vinylphosphonate formation. Morphology analysis of the Mg2+ vinylphosphonate have been performed by SEM, with an Inspect S device. Lamellar structure of the compound was observed when magnified to 100 μm scale. Lamellar structure of the compound has been revealed also by AFM using Nanosurf1 EasyScan 2 Advanced Research. Surface morphology is compact, and each layer has at its surface the vinyl phosphonic groups and water that will interfere with neighbor layer, leading to long distance regular arrangement. Compound decomposition was register by a Perkin Elmer Diamond. thermoscale and ploted in figure 2. Thermal decomposition of the Mg2+ vinylphosphonate evolve in 3 clear steps: first in 80-160°C range where 0.3 mg mass loss is attributed to water molecule, second in 160245°C range where 0.2 mg mass loss is attributed to second water molecule, and third over 420°C where one vinyl group loss occur. First two process are endothermic and last one is exothermic.

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Figure 2. Thermogravimetric curves for Mg2+ vinylphosphonate at 20°C/min heating speed Gas phase equilibrium geometry of conformers was obtained by semi-empirical PM3-RHF calculations using the Polak-Ribiere conjugate gradient algorithm for geometry optimization. Stop criteria were: SCF convergence of 10-5 and RMS gradient of 10-2 kcal/A·mol. For the structures with ½ spin number we used half electron approximation. Calculations have been performed with HyperChem7.52 package [10]. To predict the gas filtration property of Mg2+ vinylphosphonate metal organic framework, PM3 semi-empirical analysis was performed. The channels of Mg2+ vinylphosphonate metal organic framework are 5.14 x 4.93 Å in diameter (Figure 3). The gases used for this study are hydrogen, methane, carbon dioxide, carbon monoxide, sulphur dioxide and benzene (Table 1).

Figure 3. The channels of Mg2+ vinylphosphonate metal organic framework Gases

H2 N2 SO2 CO2 CO C6H6

Table 1. The gases used for this study Surface Surface Volume Refractivity Polarizability area area Å3 Å3 Å3 Aprox Å2 Grid Å2 102.36 91.89 86.43 1.60 0.77 126.56 128.53 138.63 5.4 1.91 180.11 154.97 179.99 10.68 1.14 191.89 143.21 164.86 6.38 2.42 109.16 133.95 147.36 1.95 0.57 211.86 241.06 300.89 26.06 10.43

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Mass (amu) 2.02 28.01 64.06 44.01 28.01 78.11

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CONCLUSIONS • The elementary cell is orthorhombic, slightly distorted, with hexacoordinated Mg2+ ions. IR spectroscopy confirms theoretical structure, topographic images revealing a crystalline lamellar compound. Lamellar structure of the compound was indicated also by SEM and AFM morphology analysis. Thermogravimetric analysis shows Mg2+coordinated water molecules loss occur in 80-245ºC temperature range, and vinyl group loss occur over 400ºC. • In the case of VP-9Mg, the holes of the network can filter the small molecules (N2, H2, CO, CO2 and SO2).C6H6 due to high volume and steric hindrance can not be filter by the test compound. Further investigations will be made for this preliminary study and future applications of this metal organic network will be identified. Acknowledgments: Research was partially supported by Program no 2, Project no. 2.4 from Institute of Chemistry Timisoara of Romanian Academy. LIST OF REFERENCES [1]. Clearfield A., (1998), Metal phosphonate chemistry, Progress in Inorganic Chemistry, 47, p.371-510 [2]. Stock N., Bein T, (2002), Inorganic-organic hybrid materials: hydrothermal synthesis and characterization of the metal diphosphonates M2(O3PCH2C6H4CH2PO3)·2H2O (M=Mn, Ni, Cd), Journal of Solid State Chemistry,162 (2 ),p. 330-336 [3]. Maranescu B., Vişa A., Mracec M., Ilia G., Maranescu V., Simon Z., Mracec M., (2011), Lamelar Co2+vinzlphosphonate MOFs. PM3 semiempirical analysis of structural properties, Revue. Rumanie de Chimie., 56(5), p. 473-482 [4]. Menaa B., Kariuki B. M., Shannon I. J., (2002), Preparation using metal oxide precursors and crystal structures of the copper and zinc vinylphosphonate materials, M(O3PC2H3)·H2O (M=Cu,Zn), New Journal of Chemistry, 26, p. 906-909 [5]. Matczak-Jon E., Kurzak B., Kamecka A., Sawka-Dobrowolska W., Kafarski P., (1999), Interactions of zinc(II), magnesium(II) and calcium(II) with iminodi(methylenephosphonic) acids in aqueous solutions, Journal of the Chemical Society, Dalton Transactions, p. 3627-3637 [6]. Menaa B., Shannon I.J., (2002), Synthesis and characterization of new layered mixed metal phosphonate materials magnesium-zinc phosphonates Mg1-xZnx(O3PR)·H2O and nickel-zinc phosphonatesNi1-xZnx(O3PR)·H2O using mixed divalent magnesium– zinc and nickel-zinc hydroxides, Journal of Materials Chemistry, 12, p. 350-355 [7]. Knight D. A., Kim V., Butcher R. J, Harper B. A., Schull T. L. (2002), Rhodiummediated delamination of layered copper and zinc vinylphosphonates, Journal of the Chemical Society, Dalton Transactions, p.824-826 [8]. Colodrero R.M.P., Cabeza A., Olivera-Pastor P., Choquesillo-Lazarte D, Turner A., Ilia G., Maranescu B., Papathanasiou K.E, Hix G.B., Demadis K.D., Aranda M.A.G, (2011), Divalent metal vinylphosphonate layered materials:compositional variability, structural peculiarities, dehydration behavior and photoluminescent properties Inorganic Chemistry,p..xxx-xxx [9]. Morris R E, Wheatley P S, (2008), Gas storage in nanoporous materials, Angewandte Chemie International Edition, 47, p.4966-4981 [10]. HyperChemTM, Release 7.52 for Windows, Copyright (2003), Hypercube, Inc, 1115 NW 4th Street, Gainesville, FL 32601, US.

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Reactive Yellow 125 degradation using titanium dioxide doped with N Anamaria Grozescu1,2, Liliana Colar2, Agnes Jakab2, Florica Manea2, Rodica Pode2, Nicolae Vaszilcsin2, Carmen Lazau1* 1

National Institute of Research-Development for Electrochemistry and Condensed Matter, Department of Condensed Matter, Plautius Andronescu No.1, Timisoara, Romania, 2 „Politehnica“ University of Timisoara, P-ta Victoriei No.2, 300006, Timisoara, Romania, e-mail: l_carmen@icmct.uvt.ro

ABSTRACT The aim of this paper was the syntheses of titanium dioxide undoped and doped with nitrogen ion through sol-gel method in order to degrade Reactive Yellow 125 dye from water. The obtained nanomaterials were characterized by XRD, DRUV-VIS and SEM/EDX. Ndoped TiO2 catalyst exhibited good electrocatalytic activity for RY125 discoloration and degradation under both UV and VIS irradiation, which gives a practical utility of this catalyst. Keywords: titanium dioxide, nitrogen doped titania, water treatment INTRODUCTION As recalcitrant organic pollutants continue to increase in air and wastewater streams, environmental laws and regulations become more stringent [1, 2]. Wastewaters from various industries, factories, laboratories, etc. are serious problems to the environment. Several of these chemicals such as azo dyes, herbicides, and pesticides are actually present in rivers and lakes, and are in part suspected of being endocrine-disrupting chemicals (EDCs) [3, 4]. Degradation of dyes in industrial wastewaters has therefore received increasing attention and some methods of remediation have been preferred. Traditional physical techniques (adsorption on activated carbon, ultrafiltration, reverse osmosis, coagulation by chemical agents, ion exchange on synthetic adsorbent resins, etc.) have been used for the removal of dye pollutants [5, 6]. These methods only succeed in transferring organic compounds from water to another phase, thus creating secondary pollution. This will require a further treatment of solid-wastes and regeneration of the adsorbent which will add more cost to the process. Microbiological or enzymatic decomposition, biodegradation, ozonation, and advanced oxidation processes such as Fenton and photo-Fenton catalytic reactions, H2O2/UV processes have also been used for dyes removal from wastewaters. Recent studies have been devoted to the use of photocatalysis in the removal of dyes from wastewaters, particularly, because of the ability of this method to completely mineralize the target pollutants. Titania photocatalysis also referred to as the “Honda–Fujishima effect” was first unfolded by the pioneering research of Fujishima and Honda [7]. Consequently, the application of titania photocatalysis extended to environmental frontiers [8]. Titanium dioxide (TiO2) or titania is a very well-known and well researched material due to the stability of its chemical structure, biocompatibility, physical, optical and electrical properties. The interests in TiO2-based photocatalysts have also led to the development of several methods of preparing the catalysts for varied usages. Various methods are available for the preparation of TiO2-based photocatalysts, such as electrochemical, precipitation, hydrothermal and solvothermal, sol–gel, etc [9]. 2. MATERIALS AND METHODS 2.1. N-doped TiO2 synthesis

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The materials used for the synthesis were: titanium isopropoxide (TTIP, Fluka), ethanol, distilled water, urea ((NH2)2CO2, Merk). Sol-gel (SG) method presumes the mixing of 30 mL of ethanol with 5 mL of TTIP (the precursor for Ti) added by drop wise. After a few minutes of stirring, distilled water was added also in drops. The doping precursors, (NH2)2CO2 for N-doped TiO2 synthesis, were added after the pH adjustment. The solution was continuous stirred for one hour and the obtained materials were filtered, washed and dried at 60ºC. The thermal treatment was achieved for 2 hours at 500ºC and 600ºC temperatures. 2.2. Materials characterization Phase characterization of undoped and N-doped TiO2 nanocrystals was carried out by X-ray diffraction (XRD) using a PANalytical X’PertPRO MPD Difractometer, Cu tube. The particles size and morphology of the materials were determined using Scanning Electron Microscopy (SEM) using an Inspect S PANalytical model coupled with EDX device for elemental identification. The light absorption properties of the prepared materials crystallized in pure anatase phase were studied by DRUV-VIS performed under ambient conditions in the wavelength range of 300-550 nm. 2.3. Photocatalytic measurements The photocatalytic activities of the prepared materials were assessed through degradation of 50 mg L-1 Reactive Yellow 125 in an RS-1 photocatalytic reactor (Heraeus, Germany). The volume of the reaction solution was 200 ml, into which 0.2 g of photocatalyst was added. UV and VIS irradiation was provided by a medium-pressure Hg lamp (300 W). After irradiation time of 2 hours, the suspension was sampled and filtered through a 0.2 μm membrane filter. The concentration of RY125 was measured in terms of absorbance at 225 nm and 388 nm characteristics to aromatic ring degradation and respective, discoloration with a Carry 100 Varian spectrophotometer. 3. RESULTS AND DISCUSSIONS 3.1. N-doped TiO2 nanocrystals characterization From the XRD spectra it can be seen that the sample SG-500 (spectra a, Fig.1i.) crystallized in anatase form, and for sample SG-600 (spectra b, Fig.1i.) it appeared phase transition, anatase-rutile. The specific peaks of anatase TiO2 corresponding to 2θ ~ 25.2º, 37.87º, 48.01º, 53.81°, 62.67°, 75.07 [10] and for rutile the 2 θ values are 27.5º, 30.8º, 36.4º[12]. The XRD patterns for N-doped TiO2 (Fig. 1ii) shows that the anatase phase is predominant at 500°C, and when the temperature is increased at 600°C rutile phase occurred. a. SG-N-3-500 b. SG-N-3-600

Intensity / a.u.

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b b a

a 20

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ii)

332

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011 Fig.1. XRD patterns for i) undoped TiO2 and ii) N-doped TiO2

Figure 2 presents the DRUV-VIS spectra recorded for SG-500 and SG-N-500 (Fig. 2). Spectra analysis shows that undoped TiO2 synthesized by sol-gel route adsorbs only in UV domain at the wavelength around 390 nm. The literature data presented that the anatase form of undoped TiO2 has band-gap energy about 3.2eV, which means that for electrons excitation the semiconductor needs to be expose to a radiation with the wavelength smaller or equal with 385 nm, namely in UV domain [13]. The nitrogen presence slightly shifts the spectra to VIS domain. 4,0

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Fig. 2. DRUV-VIS spectra of synthesized materials

Fig. 3. SEM image of N-doped TiO2; Inset: EDX spectra

The SEM morphology of N-doped TiO2 is shown in Fig. 3. Particles shape of doped TiO2 obtained by sol-gel method present nano-spherical morphology, highly agglomerated. EDX patterns confirm the nitrogen doping ions presence in titanium dioxide structure (Inset Fig. 3). 3.2. Photocatalytic application of N-doped TiO2 catalyst Figure 4 a-c show the results of photocatalytic application for RY125 degradation and discoloration. This exhibited a good electrocatalytic activity under both UV and VIS irradiation and as we expected the discoloration efficiency was better in comparison with aromatic ring opening (Fig. 4 a), which informed that intermediates occurred during the photocatalytic process. The aromatic ring opening is favored by acidic pH (see Fig. 4 b). Also, it is noticed that RY125 concentration increasing led to process efficiency decreasing. 100

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c) Fig.4. a)Photocatalytic process efficiency versus time under UV and VIS irradiation; 50 mgL-1RY 125, pH=3; b) Photocatalytic process efficiency versus time under VIS irradiation at different pH; 50 mgL-1RY 125 c). Photocatalytic process efficiency versus time under VIS irradiation at different RY 125 dye concentrations; pH=3

CONCLUSIONS In this study two types of materials, i.e., undoped TiO2 and N-doped TiO2 were synthesized through sol-gel method at two different temperatures of 500°C and 600°C for degradation of RY 125 from water. XRD spectra revealed that at 500°C it was obtained pure crystalline phase of anatase, and at 600°C phase transition occurred from anatase in rutile. Undoped/doped TiO2 particles synthesized by sol-gel method presented nano-spherical morphology, highly agglomerated. N-doped TiO2 catalyst exhibited good electrocatalytic activity for RY125 discoloration and degradation under both UV and VIS irradiation. The best degradation performance was achieved and acidic conditions, and higher dye concentration decreased the photocatalytic performance of this catalyst. ACKNOWLEDGEMENTS This work was partially supported by the strategic grant POSDRU 6/1.5/S/13, (2008) of the Ministry of Labour, Family and Social Protection, Romania, co-financed by the European Social Fund – Investing in People and by the Romanian National Projects, No. 72-156/2008 NANOZEOREZID. REFERENCES [1] Gogate P.R., Pandit A.B., Adv. Environ. Res 8 (2004) 501. [2] US EPA, National Emission Standards for Hazardous Air Pollutants, 40 CFR, part 63, 2006. [3] Coleman H. M., Eggins B. R., Byrne J. A., Palmer F. L., King E., Mater. Sci. Eng. B 133 (2006) 55–60. [4] Hong C.S., Wang Y., Bush B., Appl. Catal. B: Environ. 24 (2000) L1–L5. [5] Konstantinou I.K., Albanis T.A., Appl. Catal. B: Environ. 49 (2004) 1–14. [6] Prado A. G. S., Bolzon L. B., Pedroso C. P., Moura A. O., Costa L. L., Appl. Catal. B: Environ. 82 (2008) 219–224. [7] Fujishima A., Honda K., Nature (London) 238 (1972) 37. [8] Frank S.N., Bard A.J., J. Phys. Chem. 81 (1977) 1484. [9] Akpan U.G., Hameed B.H., Appl. Catal. A: General 375 (2010) 1–11. [10] Zhang X., Yao B., Zhao L., Liang C., Mao Y., J Electrochem Soc 148 (2001) 159. [12] Kamada K., Mukai M., Matsumoto Y., Electrochim Acta, 47 (2002) 3309. [13] Orha C., Manea F., Ratiu C., Burtica G., Iovi A., Environmental Engineering and Management Journal 6 (6) (2007) 541-544.

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REMOVAL OF PHARMACEUTICALS FROM WASTEWATERS BY ELECTROOXIDATION Monica Ihos*, Adriana Remes**, Dimitrie Botau*, Florica Manea ** *National R&D Institute for Industrial Ecology – ECOIND, PO Box 254 Of.1, P-ta Regina Maria Nr.2, Et.2, 300004 Timisoara, Romania, e-mail: monica.ihos@chim.upt.ro **“Politehnica” University of Timisoara, Faculty of Industrial Chemistry and Environmental Engineering, P-ta Victoriei Nr.2, 300006 Timisoara, Romania, e-mail: florica.manea@chim.upt.ro ABSTRACT The removal of the non-steroidal anti-inflammatory drug diclofenac (DCF) was carried out by electrooxidation on Dimensionally Stable Anodes (DSA) with the composition Ti/Ru0.3Ti0.7O2. The DSA electrodes were obtained by thermal decomposition of the appropriate precursors. The electrolyses were carried by using solutions of 100 mg/L DCF in 0.1 M Na2SO4 supporting electrolyte in acidic medium at various current densities and electrolysis times. The removal of DCF was assessed by recording UV-VIS spectra and chemical oxygen demand (COD) determination of the electrolysed solutions. The results showed the mineralization of the DCF during the electrooxidation on Ti/Ru0.3Ti0.7O2 electrodes. INTRODUCTION In the recent years pharmaceuticals have became a novel class of water pollutants because of their potential effects on the environment and human health at very low level of concentration [1-5]. Diclofenac (DCF) belongs to non-steroidal anti-inflammatory drugs and it is worldwide used. This group of pharmaceuticals are often found as persistent toxic waste [6]. It is known that DCF has effect on the environment. Thus, the catastrophic decline of Gyps vultures in Northern India is connected to DCF [7,8]. The pharmaceutical manufacturing industry produces a wide range of products to be used as human as and animal medications. The wastewaters from the pharmaceutical manufacturing industry may contain high organic load [9]. Therefore, it is necessary to develop effective technologies before to discharge such effluents into the sewage system [7]. A promising technology that can lead to the abatement of pharmaceuticals in the wastewaters is the electrochemical one. Electrochemical processes have major advantages for the wastewater treatment: versatility, energy efficiency, suitable to automation, environmental compatibility and cost effectiveness. The effectiveness of the electrochemical processes for the organics degradation depends on the choice of electrodes material. Dimensionally Stable Anodes (DSA) have attracted attention as electrodes for organics degradation because they exhibits great stability under electrolysis conditions [10] and they are exceptional from the point of view of the versatility [11]. The aim of this paper was the removal of DCF in acidic medium by electrooxidation at Ti/Ru0.3Ti0.7O2 DSA electrodes.

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MATERIALS and METHODS The DSA electrodes used in these experiments were Ti/Ru0.3Ti0.7O2. The electrodes were prepared by thermal decomposition of appropriate precursors. The preparation of the electrodes was reported in our previous work [12]. DCF (2-[2’,6’-dichlorophenyl)amino]phenylacetic acid) was supplied by Amoli Organics Ltd as sodium salt and sodium sulphate by Merck. Distilled water was used for the preparation of the solutions. The electrolyses were accomplished by using two DSA anodes and three stainless steel cathodes at 1 cm gap. Active surface area was 38 cm2. Experiments were carried out by applying current densities of 100, 200 and 300 A/m2 at electrolysis times of 30, 60, 120 minutes, respectively. Electrolyses were carried out in solutions of 100 mg/L DCF in 0.1 M Na2SO4 as supporting electrolyte. The pH of the working solutions was 5.5. The solutions were prepared with distilled water and Na2SO4 (Reactivul Bucureşti) reagent grade. A Specord 205 - Analytic Jena spectrophotometer controlled by computer recorded the UV spectra. RESULTS The chemical structure of DCF is shown in Fig.1 and the spectrum of DCF in 0.1 M Na2SO4 recorded in UV range in Fig.2. 3,0

Cl

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The UV spectrum of the DCF in 0.1 M Na2SO4 displayed two absorbance peaks at 277 nm and 193 nm. The degradation process of DCF is dependent on electrolysis time and current density. Thus, the variation of these parameters influenced the UV spectra shape during the electrooxidation on Ti/Ru0.3Ti0.7O2 electrodes. The UV spectra of the electrolysed solutions are shown in Fig.3-5. It can be observed the decrease of the absorbance with the increase of the current density and electrolysis time. Though, it is necessary to mention that the degradation of DCF occurred at a very small extent after 30 minutes of electrooxidation or almost at the same extent both at 30 and 60 minutes of electrooxidation.

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Fig. 4. UV spectra of DCF in 0.1 M Na2SO4

anode: Ti/Ru0.3Ti0.7O2; initial concentration: 100 mg/L; initial pH: 5.5; dilution - 1: 5; current density: 100 A/m2; electrolysis time: i – 0 min; 1 - 30 min; 2 - 60 min; 3 – 120 min

anode: Ti/Ru0.3Ti0.7O2; initial concentration: 100 mg/L; initial pH: 5.5; dilution - 1: 5; current density: 200 A/m2; electrolysis time: i – 0 min; 1 - 30 min; 2 - 60 min; 3 – 120 min

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anode: Ti/Ru0.3Ti0.7O2; initial concentration: 100 mg/L; initial pH: 5.5; dilution - 1: 5; current density: 300 A/m2; electrolysis time: i – 0 min; 1 - 30 min; 2 - 60 min; 3 – 120 min

Table 1. Working conditions and COD variation during the electrooxidation of DCF on Ti/Ru0.3Ti0.7O2 electrodes initial concentration - 100 mg/L DCF, initial COD – 140 mg O2/L

Current density / A/m2 100 200 300

400

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Cell voltage / V 3.2 3.2 3.2 3.7 3.7 3.7 4.0 4.0 4.0

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COD / mgO2/L 113.28 102.38 59.31 107.73 80.79 59.31 113.28 91.58 59.31

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Also, the degradation process of the DCF was assessed by COD of the electrolysed solutions. The results are shown in Table 1. The COD decreased with the increase of the electrolysis time for each current density. Also, no important differences of COD can be noticed among the current densities for the electrolysis time of 30 and 120 minutes. The situation is not the same for 60 minutes of electrolysis probably because of different formation rates of intermediates. CONCLUSIONS The paper dealt with the removal of non-steroidal anti-inflammatory drug DCF by electrooxidation on Ti/Ru0.3Ti0.7O2 DSA electrodes in acidic medium. The applied current densities were 100, 200 and 300 A/m2 at 30, 60 and 120 minutes of electrolysis. The UV spectra and the COD values of the electrolysed solutions revealed the mineralization of DCF during the electrooxidation process and the best result for COD abatement was 61.45% at 300 A/m2 and 120 minutes of electrolysis. LIST OF REFERENCES [1] Vonga D., Marotta R., Napolitano A., Andreozzi R., d’Ischia M. (2004). Advanced oxidation of the pharmaceutical drug diclofenac with UV/H2O2. Water Research. 38, p. 414-422. [2] Yang L., Yu L. E., Ray M. B. (2008). Degradation of paracetamol in aqueous solutions by TiO2 photocatalysis. Water Research. 42, p. 3480-3488 [3] Benotti M. J., Stanford B. D. Wert E. C., Snyder S. A. (2009). Evaluation of a photolytic reactor membrane pilot system for the removal of pharmaceuticals and endocrine disrupting compounds from water. Water Research. 43, p. 1513-1522 [4] Arye G., Dror I., Berkowitz B. (2011). Fate and transport of carbamazepine in soil aquifer treatment (SAT). Chemosphere. 82, p. 244-252 [5] Varga M., Dobor J., Helenkar A., Jurecska L., Yao J., Zaray G. (2010). Investigation of acidic pharmaceuticals in river and sediment by microwave-assisted and gas chromatography-mass spectrometry. Microchemical Journal. 95, p. 353-358 [6] Mendez-Arriaga F., Esplugas S., Gimenez J. (2008). Photocatalytic degradation of nonsteroidal anti-inflammatory drugs with TiO2 and simulated solar irradiation. Water Research. 42, p. 585-594 [7] Rizzo L., Meric S., Kassinos D., Guida M., Russo F., Belgiorno V. (2009). Degradation of diclofenac by TiO2 photocatalysis: UV absorbance kinetics and process evaluation through a set of toxicity bioassay. Water Research. 43, p. 979-988 [8] Kummerer K. (2009). The presence of pharmaceuticals in the environment due to human use – present knowledge and future challenges. Journal of Environmental Management. 90, p. 2354-2366 [9] Chelliapan S., Wilby T., Sallis P.J. (2006). Performance of an up-flow anaerobic stage reactor (UASR) in the treatment of pharmaceutical wastewater containing macrolide antibiotics. Water Research. 40, p. 507-516 [10] Malpass G. R. P., Miwa D. W., Miwa A. C. P., Machado S. A. S., Motheo A. J. (2009). Study of photo-assisted electrochemical degradation of carbaryl at dimensionally stable anodes (DSA®). Journal of Hazardous Materials. 167, p. 224-229 [11] Trasatti S. (2000). Electrocatalysis: understanding the success of DSA®. Electrochimica Acta. 45, p. 2377-2385 [12] Ihos M., Bogatu C., Iovi A. (2004). Degradation of Reactive Blue 4 at DSA Electrode. Chemical Bulletin of „POLITEHNICA” University of Timisoara. 49 (63), p. 105-107

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ELECTROCHEMICAL BEHAVIOR AND DETERMINATION OF ARSENIC (III) FROM WATER USING AG-DOPED –ZEOLITECARBON NANOTUBES COMPOSITE ELECTRODE Anamaria Baciu1, Adriana Remes1, Aniela Pop1, Florica Manea1*, Georgeta Burtica1, 1

“Politehnica” University of Timisoara, Sqr. Victoriei no.2, 300006 Timisoara, Romania, email: anamaria.baciu@chim.upt.ro ABSTRACT The electrochemical behavior of Arsenic (III) from water was investigated using Agdoped–synthetic zeolite-carbon nanotubes composite electrode envisaging its determination in the aqueous solution. The electrocatalytic oxidation of arsenic in acidic medium at Ag-doped –synthetic zeolite-carbon nanotubes composite electrode (Ag-ZCNT) was investigated by cyclic voltammetry, with different practical working pretreatment applications. INTRODUCTION Arsenic occurs in the natural environmental in the earth’s crust, in soil, rocks and minerals. It exists in four oxidation states e.g. arsenate (+V), arsenite (+III), arsenic (0), and arsine (–III) [1]. Arsenic has been used widely in pigments, insecticides and herbicides, glass manufacture and veterinary chemicals [2]. Arsenic is highly toxic to both plants and animals and chronic exposure to arsenic can cause a variety of adverse health problems [3]. A wide variety of methods to determine arsenic have been used, many based on spectrometry methods [4]. However, the methods based on these techniques are timeconsuming and requires expensive instrumentations and complicated procedure [5]. Electrochemical detection techniques provide an attractive alternative to determine arsenic and arsenic compounds at low concentrations and due to low-cost instrumentation, simple operation and rapid analysis time. Different electrodes, such as mercury, [6], gold, [7], platinum [8] silver, [9] were used to detect arsenic by voltammetric techniques. However, there are often problems associated with arsenic voltammetry at such electrodes, due to the potential toxicity of Hg electrode, or general limitations for the sensitivity and selectivity of the other electrodes. These problems may be solved by using metallic nanoparticles nanotubes modified electrodes, which can enhance the electrocatalytic activity and selectivity towards the oxidative detection of arsenic. This work aimed to describe the electrochemical behavior of arsenic on the composite electrode and the determination of Ag-doped–synthetic zeolite-carbon nanotubes composite electrode. The electroanalytical parameters for the detection of arsenic in 0.09 M Na2SO4 and 0.01 M H2SO4 supporting electrolyte were determined by cyclic voltammetry (CV). MATERIALS and METHODS Materials The epoxy resin used in the study was Araldite®LY5052/ Aradur®5052 purchased from Huntsman Advanced Materials, Switzerland. Multiwall carbon nanotubes (CNT) synthesized by catalytic carbon vapour deposition were produced by NanocylTM, Belgium. Atype syntetic zeolite was prepared using natural zeolite from Mirsid, Romania, with 68% wt. clinoptilolite as a silicon source and sodium aluminate as aluminium source, and Ag-doped synthetic zeolite was obtained by ion-exchange process.

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Preparation of Ag-ZCNT composite electrodes The dispersion of MWCNT in tetrahydrofuran, 99.9% (THF, Sigma Aldrich) was achieved by ultrasonication using a Cole-Parmer® 750-Watt Ultrasonic Processor for about 10 min prior to mixing with the polymer resin. After the sonication process, the solution of MWCNT/THF was sonicated again with epoxy resin to obtain a more homogeneous mixture. An effective method, two roll mill (TRM) of achieving high levels of dispersion and distribution was used to prepare the Ag-ZCNT composite electrode. The ratio between the components was chosen to reach 20-weight percent (w/w) content of CNT, 20weight percent (w/w) content of silver-doped synthetic zeolite. During processing the temperature was kept constant at 70oC, the mixing speed was maintained at 10 and 20 rpm for about 40 min. Then the zeolite doped with Ag was mixed with CNT and after then the curing agent (weight ratio of epoxy resin:curing agent was 100:38) was added to MWCNT. The mixture was then poured into PVC tubes and cured in a vacuum oven at 80oC for 24h, after which it was left to cool down at room temperature. Prior to use, the working electrode was gradually cleaned, first polished with abrasive paper and then on a felt-polishing pad by using 0.3 μm alumina powder (Metrohm, Switzerland) in distilled water for 5 minutes and rinsing with distilled water. Electrochemical measurements The electrochemical performance of this electrode was studied by cyclic voltammetry (CV). An electrochemical pre-treatment by three repetitive cyclings from 0 V to +1.0 V vs. SCE in 0.1 M in 0.09M Na2SO4 and 0.01M H2SO4 supporting electrolyte was performed. All measurements were carried out using an Autolab potentiostat/galvanostat PGSTAT 302 (Eco Chemie, The Netherlands) controlled with GPES 4.9 software and a three-electrode cell, with a saturated calomel electrode as reference electrode, a platinum counter electrode, and the composite working electrode. RESULTS Voltammetric determination To examine de ability of the Ag-ZCNT composite electrode as a tool in arsenic determination in aqueous solutions, an initial test of this electrode were carried out by cyclic voltammograms in 0.09 M Na2SO4 and 0.01 M H2SO4 supporting electrolyte solution in 1 mgL-1 As (III), in potential range of 0 to 1.0 V/SCE, scan rate of 50 mV/s with a preconditioning step that consisted in a reduction process of As (III), which was chosen at 0.5 V/SCE in according with the literature [9]. Without this preconditiong step no signal corresponding to arsenic presence was found (the results are not shown here). The presence of arsenic led to increasing oxidation current starting with the potential value of about +0.2 V/SCE and the best signal was found at the potential value of about +0.5 V/SCE, which was selected for arsenic determination. To determine the optimum working conditions for arsenic determination, the potential value of -0.5 V/SCE was applied at different conditioning time, i.e., 10, 20, 30, 60 and 120s. Based on the results presented in Fig 1a, the optimum preconditioning time of 60 s was selected. Also, different potential values, i.e., of -0.25, -0.5, -0.75, and -1.0 V/SCE were applied at a preconditioning time of 60s, and the results are shown in Fig. 1b. Based on these results, the further measurements were performed at the potential values of -0.5V/SCE for 60s, and -0.75V/SCE for 60s. Fig. 2 (a) and (b) show the cyclic voltammograms of Ag-ZCNT composite electrode at various As(III) concentrations ranged from 0.1 to 1 mgL-1 (curves 2-11), in 0.09 M Na2SO4

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and 0.01 M H2SO4 supporting electrolyte solution, within potential range of 0 to 1.0 V/SCE, at the scan rate of 50 mV/s with preconditioning potential value of -0.5V/SCE for 60s, and respective, -0.75V/SCE for 60s. 0.058 0.065

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b) a) Fig. 1. The useful signals corresponding to 1 mgL-1 arsenic determined by cyclic voltammograms of Ag-ZCNT composite electrode in 0.09 M Na2SO4 and 0.01 M H2SO4 supporting electrolyte solution in, with a preconditioning of electrode at -0.5V/SCE at deposition time of 10, 20, 30, 60 and 120s, (a), and with a preconditioning time of 60s at the potential values of -0.25, -0.5, -0.75, and -1.0 V/SCE (b) 0.5

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Fig. 2.a- Cyclic voltammograms at Ag-ZCNT composite electrode in 0.09 M Na2SO4 and 0.01 M H2SO4 supporting electrolyte (1) and in the presence of 0.1-1 mgL-1 arsenic (curves 211); potential scan rate: 0.05 Vs-1; potential range: 0 to +1.0 V/SCE, with preconditioning at 0.5V/SCE for 60 s. Inset:The calibration plot of the currents recorded at E= +0.50 V/SCE vs. arsenic concentration. b- Cyclic voltammograms at Ag-ZCNT composite electrode in 0.09 M Na2SO4 and 0.01 M H2SO4 supporting electrolyte (1) and in the presence of 0.1- 1 mgL-1 arsenic (curves 2- 11); potential scan rate: 0.05 Vs-1; potential range: 0 to +1.0 V/SCE, with preconditioning at -0.75V/SCE for 60 s. Inset: The calibration plot of the currents recorded at E= +0.50 V/SCE vs. arsenic concentration. CONCLUSIONS The silver-doped synthetic zeolite-multiwalled carbon nanotube-epoxy (Ag-ZCNT) composite electrode showed a good electrocatalytic behavior for arsenic oxidation in 0.09 M 0.09 M Na2SO4 and 0.01 M H2SO4 supporting electrolyte but only with a preconditioning step imposed for arsenic reduction, which requires stripping voltammetric analysis method applying. Even if for both preconditioning potential values of -0.5 and -0.75V/SCE for 60 s the linear dependence of anodic peak current versus arsenic concentration was found, the best sensitivity for arsenic determination was found at the potential value of -0.5V/SCE, which was selected as optimum one. The electrocatalytic behavior of this electrode against arsenic oxidation together with easy preparation and regeneration by a simple polishing of the electrode surface, give it a potential for the practical quantitative determination of arsenic in real samples.

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LIST OF REFERENCES [1] Bissen M., Frimmel F. H., (2003). Arsenic – a Review. Part I: Occurrence, Toxicity, Speciation, Mobility, Acta hydrochimica et hydrobiologca. 31, p 9–18; [2] Munoz E., Palmero S., (2005). Analysis and speciation of arsenic by stripping potentiometry: a review, Talanta 65, p 613–620; [3] Luong J.H.T., Majid E., Male K.B., (2007). Analytical Tools for Monitoring Arsenic in the Environment. The Open Analytical Chemistry Journal, 1, p 7-14. [4] Matoušek T., Hernández-Zavala A., Svobod M., Langrová L., Adair B. M., Drobná Z., Thomas D. J., Stýblo M., Dědina J., (2008). Oxidation state specific generation of arsines from methylated arsenicals based on L-cysteine treatment in buffered media for speciation analysis by hydride generation-automated cryotrapping-gas chromatography-atomic absorption spectrometry with the multiatomize, Spectrochimica Acta Part B 63, p 396–406; [5] X. Dai, Compton R. G. (2006). Direct Electrodeposition of Gold Nanoparticles onto Indium Tin Oxide Film Coated Glass: Application to the Detection of Arsenic (III) Analytical Sciences. 22, p 567-570; [6] Forsberg G., O'Laughlin J. W., Megargle R. G., (1975). Determination of Arsenic by Anodic Stripping Voltammetry and Differential Pulse Anodic Stripping Voltammetry, Analytical Chemistry. 47, p 1586-1592; [7] Xiao L., Wildgoose G. G., Compton R. G., (2008). Sensitive electrochemical detection of arsenic (III) using gold nanoparticle modified carbon nanotubes via anodic stripping voltammetry, Analytica Chimica Acta. 620, p 44-49; [8] Shin S.H., Hong H.G., (2010). Anodic Stripping Voltammetric Detection of Arsenic (III) at Platinum-Iron (III) Nanoparticle Modified Carbon Nanotube on Glassy Carbon Electrode, Bulletin of the Korean Chemical Society 31, p 3077-3083; [9] Simm A. O., Banks C. E., Compton R. G., (2005). The Electrochemical Detection of Arsenic (III) at a Silver Electrode, Electroanalysis 17, p 1727 – 1733. ACKNOWLEDGEMENTS This work was partially supported by the strategic grant POSDRU/88/1.5/S/50783, POSDRU/21/1.5/G/13798, POSDRU/89/1.5/S/57649, (PERFORM-ERA), co-financed by the European Social Fund – Investing in People, within the Sectoral Operational Programme Human Resources Development 2007-2013 and partially by the PNII-72-156/2008.

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POLYALUMINUM CHLORIDE COAGULATION IN DRINKING WATER TREATMENT Smaranda Masu National Research and Development Institute for Industrial Ecology ECOIND, Piata Regina Maria no.1, 300251, Timisoara, Romania e-mail: smarandamasu@yahoo.com

ABSTRACT Dissolved organic matter, DOC [mg C/L], is a representative parameter for the content of organic matter in natural waters. Along the A254 absorbance as a measure of organic compounds determined at λ = 254nm UV [cm-1], DOC underlies the calculation of SUVA (Specific Ultraviolet Absorbance) = A254/DOC x 100 [L·m-1·mg-1]. SUVA can be used to describe the composition of the water in terms of hydrophobic / hydrophilic character. The study results are presented in the coagulation process with pre-hydrolyzed aluminum salt, as a polyaluminum chloride (PACl), a simple salt of Al, as an Al sulfate (Alum), applied to surface water intended for drinking water. From SUVA values DOC removal efficiency in the coagulation process is estimated. SUVA = 2-4 estimated efficiencies of 25-50% removal in DOC. When using PACl, DOC removal efficiency is within the range of 27-53%, and slightly lower when using Alum. SUVA values <2 indicate DOC removal efficiencies <25%. DOC removal efficiencies obtained from the use of Alum are within the range 5.6-8.4% and those obtained when used as coagulation agent PACl are in the range 20.8-23.8%. INTRODUCTION Coagulant agents are those that govern the efficiency of coagulation and formation of sedimentary aggregates. It is known that multi-species metal ions, such as Al and Fe, can form dimers and trimers. After the addition of Al and Fe salts in water, they pass through a sequence of stages of hydrolysis, polymerization, aggregation and precipitation which results in a multitude of instable and transient species. This underlies the explanation that these forms are based on conversion of monomers into polymers that are present both in soluble form and precipitates and gels [1-3]. Hydrolysis of polymeric aluminum salts is different from that of simple salts such as aluminum sulphate (Alum). The degree of hydrolysis of polymeric salts can be controlled during manufacturing technology and the speed formation of precipitate after dilution polymer coagulant [4-6]. Polymeric aluminum species (Aln) forming capacity increases with increasing the degree of neutralization Al polynuclear hydrolysis product has great practical importance, and it was designated Al13 (Al13O4)(OH)24+7). The proportion of polymer is 33% to 83% for a value of B increasing from 1 - 2.5 (B = OH/Al, molar ratio). Results were confirmed by other tests. The species is regarded as the best species for coagulation [5]. Two main mechanisms are considered that can be used to explain the phenomena of coagulation: compressing the electrical double layer of colloidal particles, adsorption, charge neutralization and precipitation, neutralization of charges, including and sweeping of impurities by precipitation of hydrolyzed species. Actually, both mechanisms occur, but one predominates. Predominant mechanism depends on the type of coagulant, the source of water treated, the technique of adding coagulants etc. [3.6]. Hydrolysis / precipitation of the pre-hydrolyzed aluminum salt, as a polyaluminum chloride (PACl type),

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coagulating agents depend on the type of coagulant, water pH, the dose used, etc. [5-6]. The study presents the comparative effectiveness of removing dissolved organic matter (DOC) [mg C/L] in the coagulating process by hydrolyzed salt, PACl and simple salt, Alum, for sources of surface water intended for drinking water. Representative parameters to characterize organic matter content (NOM) of natural waters are the contents of dissolved organic carbon, DOC and UV absorbance at 254nm, A254 [cm-1]. Also natural organic natter characterization of water is done using the Specific Ultra Violet Absorbance parameter, SUVA, introduced by Tobiason and Edzwald [7]. SUVA calculation is performed with the DOC and A254 ratio, SUVA = A254/DOC x 100 [L·m-1·mg-1]. SUVA can be used to describe the composition of the water within hydrophilic/hydrophobic character. Waters characterized by SUVA > 4 show a hydrophobic character with aromatic compounds, and those characterized by SUVA < 2 indicate a predominantly hydrophilic character [8]. MATERIALS and METHODS For this study, 10 of the representative waters supplies used for drinking water were studied. The analyzed parameters are: DOC for filtrated water samples, trough 0.45 µm filter. Raw and coagulated samples were filtered through 0.45 μm pre-rinsed filter by type of SPARTAN 3D/0.45 RC, Whatman Inc. SUA. DOC was measured using a Multi C/N 2100S TOC analyzer (Analytik Jena); A254 are the values of ultraviolet absorbance at 254 nm, of the filtrate samples (0.45 µm). The absorbance was determined using a Specord 205 UV/VIS spectrophotometer Analytik Jena in a 1 cm3 quartz cuvette. SUVA is a specific ultraviolet absorbance, determined as the absorbance at 254 nm (A254) [cm-1], per unit of DOC [mg C/L] and SUVA= A254/DOC x 100 [L·m-1·mg-1]. The coagulant agents used are: Alum, Al2(SO4)3*18H2O reagent, provided by Chimopar Bucuresti and poly-aluminum chloride, PACl are obtained by controlled reaction of aluminium salts with base under carefully controlled conditions [9]. PACl is characterized by B= 2.4 and was obtained by reaction of aluminum salts with a base under carefully controlled conditions. They are typically characterized by degree of neutralization expressed as “B” which is the ratio OH/Al total [6]. Jar Test method: coagulation experiments were carried out using Degremont Jar Test in 1L beakers. After the addition of the coagulants, the samples were subjected to rapid mixing for two minutes at 250 rpm, then flocculation 10 minutes at 25 rpm and the settling for 30 minutes. RESULTS Table 1 shows the values for DOC, A254 and SUVA of untreated water sources. DOC parameter values characteristic for water sources are studied within the range of 2.58-8.05 [mg C/L], A254 parameter values are within the range 0.063-0.206 [cm-1]. The values of the water sources quality parameters covered very wide areas. Among the factors that influence the composition and concentration of DOC, present in water sources for drinking water, may be: the precipitation regime that leads to the formation of torrents that involve such large quantities of organic and inorganic suspensions in hydrographic area; the amount of dead organic matter accumulated during the cold storage of the year, at different stages of humidification, thermal regime, topography, etc. As a result of fluctuations in composition and concentration of dissolved organic matter was necessary to introduce the SUVA parameter through which we can estimate the dissolved organic compounds character and

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their removal efficiencies when using coagulating agents. SUVA values for the studied water supplies are within the range 2.11-3.48 [L·m-1·mg-1]. The water supplies studied have values of SUVA = 2-4 [L·m-1·mg-1], which indicate the presence of a mixture of water compounds with hydrophilic and hydrophobic character. For this type of water sources there is an estimated removal efficiency between 25-50% in DOC. DOC removal efficiencies obtained from applying the optimal dose of coagulating agents, Alum and PACl, are shown in Figure 1. DOC removal efficiencies obtained from the use of PACl for water sources characterized by parameter SUVA=2-4 [L·m-1·mg-1], are shown in Figure 1. DOC removal efficiencies are within the range 27-53%. DOC removal efficiencies are in the range estimated by the SUVA values. The use of Alum determined lower reduction efficiencies of DOC vs. removal efficiencies obtained when using PACl coagulation agent. DOC removal efficiencies when using Alum as coagulation agent are within the 7-49% range. Note that for A_1 and A_4 water sources DOC reduction efficiencies at alum as coagulation agent are 7.0 and 15.2% respectively under the estimated level (see figure 1). The cause of this behavior is due firstly to the hydrophobic organic matter present in water sources and secondly to the Al species involved in the coagulation process. Species with coagulant action present in the pre-hydrolyzed agents, PACl have a greater capacity for removing DOC for optimal doses similar to the optimal doses of Alum.

DOC removal efficiency [%]

Table 1 The values for DOC, A254 and SUVA of untreated water supplies Nr. Water DOC Absorbance SUVA -1 Crt. supply [mgC/L] 254nm [cm ] [L·m-1·mg-1] 1 A_1 2.58 0.063 2.44 2 A_3 3.22 0.082 2.49 3 A_4 3.29 0.089 2.70 4 A_6 2.22 0.068 3.06 5 A_7 6.33 0.174 2.74 6 A_8 5.93 0.155 2.61 7 A_9 7.53 0.159 2.11 8 A_10 8.04 0.162 2.36 9 A_12 3.01 0.105 3.48 10 A_13 8.05 0.206 2.56

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Figure 1. DOC removal efficiencies obtained from optimal doses of coagulant agents, Alum and PACl, water supplies with SUVA = 2-4

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CONCLUSIONS Natural factors influence the composition and concentration of DOC in raw waters. Water supplies studied have a variable content of DOC and different compositions of natural organic matter. SUVA parameter can be used to describe the composition of water within hydrophobic / hydrophilic character and therefore DOC removal efficiency is estimated. The hydrophilic/hydrophobic character determines reductions between 25-50%, confirming the SUVA estimates. The use of pre-hydrolyzed salts, PACl, leads to greater removal efficiencies vs. DOC removal efficiencies obtained when using Alum. LIST OF REFERENCES [1] Edzwald, J.K. (1993). Coagulation in drinking water treatment: Particles, Organics and Coagulants, Water Science and Technology, 27, 11, p. 21–35 [2] Letterman, R.D., Amirtharajah A., O Melia C.R. (1999). Coagulation and Flocculation in Water Quality and Treatment, 5th edition, (Letterman R.D., ed), Chapter 6, New York, Mc. Graw Hill Inc., p. 6.1-6.65. [3] Edzwald, J. K., Van Benschoten, J. E. (1990). Aluminum Coagulation of Natural Organic Material in Chemical Water and Wastewater Treatment, (Hahn H.H. and Klute R. Eds), New York, Berlin Springer Verlag, p. 341-359. [4] Mâşu S. (2011). Simultaneous Reduction of Turbidity and Natural Organic Matter by Simple and Prehydrolyzed Aluminum Salts, Revista de chimie, 62, 1, p. 64-68. [5] Pernitsky, D. J. Edzwald, J. K. (2006). Selection of Alum and Polyaluminum Coagulants Principles and Applications, Journal of Water Supply Research and Technology Aqua, 55, 2, p. 121-141. [6] Duan, J. Gregory J. (2003). Coagulation by Hydrolyzing Metal Salts, Advances in Colloid and Interface Science, 100-102, p. 475-502. [7] Edzwald, J.K., Tobiason, J.E. (1999). Enhanced Coagulation: US Requirements and a Broader View, Water Science and Technology, 40, No. 9, p. 63-70. [8] Eikebrokk B., Juhna T., Osterhus S.W. (2006). Techneau WP 5.3.1 Operation of Water Treatment Facilities – Optimization effort and modelling in unit process operation, Coordinator of project Hoven T.V., Nieuwegen, Olanda, p. 10-26. [9] Mâşu S., Andres L., Rus V., Bogatu C., Botău D., Cocheci D., Demetrovici L., Demetrovici L. C., Chira D., (2009), Brevet RO 122630 B1.

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HEAVY METALS IN PLANTS GROWN ON NEW FLY ASH DEPOSITS Smaranda Masu*, Valeria Rus*, Luminita Jurj**,Nicolae Dragomir***, Stela Uruioc**** *National Research and Development Institute for Industrial Ecology-ECOIND, Piata Regina Maria no.1, 300251, Timisoara, Romania; e-mail: smarandamasu@yahoo.com ** “Politehnica” University of Timisoara, Piata Victoriei no. 2, 300006 Timisoara, Romania ***Animal Sciences and Biotechnologies Faculty, Calea Aradului 119, 300645, Timisoara, Romania **** West University of Timişoara, Chemistry, Biology and Geography Faculty, Str. Pestalozzi 16, 300115, Timisoara, Romania. ABSTRACT The paper presents the results of studies with leguminous species grown on experimental parcels of new fly ash fertilized with biosolids (municipal sludge) and untreated indigenous volcanic tuff or pillared indigenous volcanic tuff. Fly ash comes from the dumps of ash from burning lignite in power plants. The resulting amount of biomass grown on new fly ash deposits is dependent on the treatment of topsoil (new fly ash). The experimental variants with new fly ash treated with biosolids and pillared indigenous volcanic tuff determined 50% germination and an increase of harvest by 2.5-2.7 times vs. others. In addition, the treatment of new fly ash with pillared indigenous volcanic tuff and biosolids caused a reduction in the bioaccumulation of heavy metals in the aerial part of plants by 35-45%, for Cu respectively Ni, 60 % for Cr, and 78% for Pb. INTRODUCTION Studies on the development and behavior of plants growing on new fly ash dumps are a forward step in the context of ecological studies in the world with special significance [1-3] The addition of bio fertilizers of the organic-zeolite kind has greater advantages than the addition of chemical fertilizers. Numerous examples in literature are given on the properties of a component, that is, volcanic tuff, as clinoptilolite that when used as addition of biodegradable organic waste to initiate and maintain components of nitrogen (ammonia, nitrogen etc.) and gradually releasing it for the needs of the plant. In this way the loss of volatile nitrogen compounds in the environment (atmosphere) is much reduced [4-5]. It was also shown a similar effect when the soil is polluted with heavy metals and fertilizer organic-zeolite treated. Population development studies in soils fertilized with organic-zeolite bacterial support shows that the quantity of microorganisms increased 2.5 times and soil quality changes. The microbial activity in soil fertilized with organic-zeolite fertilizers did not decrease during winter as shown for the addition of mineral fertilizers [6]. The addition of soil amendments as volcanic tuff for polluted soils reduces the metal accumulation in different parts of the plant [7]. The study was to determine the influence of treated topsoil (top layer of new fly ash deposits):

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1. The degree of vegetation of new fly ash deposit; 2. The amount of biomass harvested (leguminous species); 3. Bioaccumulation of heavy metals in the aerial parts of the plants and the toxic potential of metals.

MATERIALS and METHODS The study is carried out on four experiments: new fly ash fertilized with biosolids mixed with pillared indigenous volcanic tuff, [8], new fly ash fertilized with biosolids mixed with untreated indigenous volcanic tuff, new fly ash fertilized with biosolids, new fly ash / blank experimental parcels (three replicas for each experiment). The experimental area had 3 m2 and the distance between the experimental parcels was 1 meter. New fly ash was fertilized with municipal sludge 25t/ha DM (biosolids). The biosolids used had the following characteristics: total nitrogen 0.73%, phosphorus 0.75%, and pH 6.5. The amount of indigenous volcanic tuff and pillared indigenous volcanic tuff was 2% wt. The indigenous volcanic tuff contains up to 70% clinoptilolite and comes from the Mirsid quarry, Romania, and the pillared indigenous volcanic tuff is prepared according to patent [8]. Table 1 shows the content of heavy metals in the topsoil of experimental parcels. Table 1. Content of heavy metals in the topsoil of experimental parcels. Average content of heavy metals in topsoil [mg/kg D.M.] Experimental Nr.crt. parcel* Cr Cu Fe Ni Pb Zn New fly ash + 1 pillared tuff + 84.6 67.1 4,731.8 50.1 13.7 84.5 biosolids New fly ash + 2 84.0 66.1 4,636.4 48.0 12.9 83.3 tuff + biosolids New fly ash 3 85.6 65.9 4,711.9 49.3 14.1 82.6 +biosolids 4 New fly ash 85.8 63.8 4,636.4 50.1 12.9 65.8 * three replicas for each experimental variant Topsoil sample analysis was done to determine the total iron, zinc, copper, chromium, nickel and lead concentrations according to the analysis method: heavy metals were extracted from the soil samples by heating with Aqua Regia for 2 hrs, at reflux. After interrupting the heat, the system was left in stand-by for 16 hrs. Then the samples were diluted in a flask with deionized water to exactly 50 ml. The Onobrochis viciifolia specie was selected to be planted into the experimental parcel. Plant tissues were thoroughly washed with de-ionized water to remove any soil particles attached to plant surfaces. The tissues were dried (105°C) to a constant weight. Plant samples with constant weight are then brought to 550°C; to the residual materials 5ml of concentrated hydrochloric acid are added, samples are maintained 30 minutes on the dry sand bath. After filtering those in a paper filter with small porosity, they were taken to a calibrated flask with hydrochloric acid 1:1 solution. Plant and soil extracts analysis was done using a spectrophotometer, Varian Spectra AAS. The detection limit of the device is 0.001 mg/l.

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RESULTS Table 2 shows germination and vegetation degree of parcels cultivated with Onobrochis viciifolia and the amount of biomass harvested from mature plants. Onobrochis viciifolia species does not grow on the experimental parcels of untreated new fly ash. Parcels fertilized with biosolids determine a delay in plant growth. During harvesting, land surface is covered with plants grown at a rate of 35%. Addition of unmodified tuff has the effect of increasing the number of plants that grow on this experimental variant. Although the area covered by plants reaches 50% the amount of harvested biomass is much lower than when using the pillared tuff. Table 2 shows the amount of biomass harvested from the fly ash + pillared tuff + biosolids parcels 2.5-2.7 times higher vs. new fly ash + tuff + biosolids or new fly ash + biosolids biomass harvest. Table 3 shows the content of heavy metals in Onobrochis viciifolia aerial plant tissue of plants Table 2. Germination and vegetation degree of parcels cultivated with Onobrochis viciifolia and the amount of biomass harvested from mature plants. Germination Coverage Blanquet – Harvest Nr.crt. Experimental parcels degree degree Braun scale [kg/ha] [%] [%] coverage New fly ash + pillared Level 3 1 indigenous tuff + 50 50 3050 25-50% biosolids New fly ash + Level 3 2 indigenous tuff + 50 45 1250 25-50% biosolids Level 3 3 New fly ash +biosolids Some plants 35 1125 25-50% 4 New fly ash No plants Table 3. Content of heavy metals in Onobrochis viciifolia aerial plant tissue. Content of heavy metals in Onobrochis viciifolia Nr. Experimental aerial plant tissue [mg/kg D.M.] crt. parcels Cr Cu Fe Ni Pb Zn New fly ash + pillared 1 3.3 6.5 3,793.7 2.9 0.6 24.2 indigenous tuff + biosolids New fly ash + 2 indigenous tuff + 8.3 9.7 4,488.9 5.7 2.3 25.2 biosolids New fly ash + 3 8.0 9.6 4,523.9 5.3 4.1 36.7 biosolids 4 New fly ash* * no plant Table data shows that the addition of fertilizer/biosolids and fertilizer/biosolids and unmodified tuff caused similar bioaccumulation of heavy metals (chromium, copper, iron, nickel and zinc) in tissue of the aerial part of growing plants. Plants grown on experimental

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parcels new fly ash + pillared indigenous tuff + biosolids bioaccumulated smaller amounts of heavy metals in the aerial parts of plants (35% less for Cu, 45% for Ni, 60% for Cr and 78% for Pb). Pillared indigenous volcanic tuff (treated tuff) has the ability to reduce the access of certain heavy metals in plants of Onobrochis viciifolia species. CONCLUSIONS 1. Onobrochis viciifolia species did not grow on new deposits of new fly ash deposits. 2. The addition of fertilizer as biosolids resulted in reduced germination of seeds and a surface covered with vegetation by 35%. 3. The addition of fertilizer mixed with unmodified indigenous volcanic tuff caused good germination of seeds and vegetation cover of 45%. 4. The addition of fertilizer mixed with pillared indigenous volcanic tuff determined good development of crops. The amount harvested was 2.4-2.7 times higher than that obtained in other variants. At the same time pillared indigenous volcanic tuff caused heavy metals reduction in the aerial part of plants in the following order: 35% for Cu, 45% for Ni, 60% for Cr and 78% for Pb. This is a good new fly ash vegetation variant. LIST OF REFERENCES [1] Haynes, R.J., (2008), Reclamation and Revegetation of Fly Ash Disposal Sites – Challenges and research needs, Journal of Environmental Management, 90, p. 43-53. [2] Adriano, D.C., Page, A.L., Elseewi, A.A., Chang, A.C., Straughan I., (1980), Utilization and Disposal of Fly Ash and Other Coal Residues in Terrestrial Ecosystems: A Review, Journal of Environmental Quality, 9, p. 333-344. [3]. Mitrovici L., Pavlovici P., Lakusic D., Djurdjevic, L. Stevanovic B., Kostic O., Gajic G., (2008), The potential of Festuca rubra and Calamagrostis epigenos for the Revegetation of Fly Ash Deposits, Science of the Total Environment, 407, p. 338- 347. [4]. Leggo P.J., Ledesert B., Christie G., (2006), The Role of Clinoptilolite in OrganoZeolitic-Soil Systems Used For Phytoremediation, Science of the Total Environmental, 363, p 1-10. [5]. Mâşu S., Pricop A., Morariu F., (2010), Studies Regarding the Decrease of Heavy Metal Accumulations in Herbaceous Plants Tissues Grown on Fly Ash Dumps, Scientific Paper: Animal Sciences and Biotechnologies, vol. 43 (2), p. 103-106. [6]. Machulla G., Zkeli S., Kastler M., Jahn R., (2004), Microbial Biomass And Respiration In Soils Derived From Lignite Ashes : Profile Study, Journal of Plant Nutrition and Soil Science, 167, 499-456. [7]. Maiti S.K., Shishir J., (2008), Bioaccumulation and Translocation of Metals in the Natural Vegetation Growing on Fly Ash Lagoons: A Field Study From Santaldih Thermal Power Plant, West Bengal, India, Environmental Monitoring and Assessment, 136, p. 355-370. [8] Mâşu S., Andres L., Rus V., Bogatu C., Botău D., Cocheci D., Demetrovici L., Demetrovici L. C., Chira D., (2009), Brevet RO 122630 B1.

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COLOUR EXPRESSION IN THE CIELAB COLOUR SCALE OF NEW STILBENE DYES Grad Maria Elena a, Muntean Simona Gabriela a, Simu Georgeta Maria b a

Institute of Chemistry Timisoara of Romanian Academy, B-dul Mihai Viteazul 24, 300223 Timişoara, România b University of Medicine and Pharmacy “V. Babeş” Timişoara, Faculty of Pharmacy, Eftimie Murgu 2, 300041 Timişoara, România e-mail:marilena_grad@yahoo.com ABSTRACT Using the well known CIELAB colour space parameters: lightness (L*), redness (a*), yellowness (b*), chroma (C*) and hue angle (hº) relative to the standard illuminants D65 (natural day light), A (tungsten light), and the standard 10º observer, the colour expression of two new symmetrical direct disazo-stilbene dyes was performed. The colour differences ΔEab* and ΔECMC were calculated against one standard, indicating a high colouring power of the both disazo-stilbene dyes. The studied dyes were synthesized using 4,4'diaminostilbene-2,2'-disulphonic acid as middle eco-friendly component and 2-methyl-Nacetoacetanilide and 5-acetoacetylaminobenzimidazolone as coupling components respectively. INTRODUCTION Colour is extremely subjective and personal. To try to attribute numbers to the brains reaction to visual stimuli is very difficult. The aim of colour spaces is to aid the process of describing colour, either between people or between machines or programs. In 1976 the CIE (Commission Internationale d'Eclairage) recommended the CIE L*a*b or CIELAB color scale for use. It was intended to provide a standard, approximately uniform color scale which could be used by everyone so that color values could be easily compared. In a uniform color scale the differences between points plotted in the color space correspond to visual differences between the colors plotted. Over 40 colour difference formulae have been developed since the first CIE colorimetric system. Most of the colour-difference formulae were developed to fit data sets having a limited range of colour-difference magnitudes. [1] In this work the colorimetric analysis by the CIELAB parameters of two new disazo stilbene dyes with symmetrical structure derived from 4,4'-diaminostilbene-2,2'-disulphonic acid is presented. MATERIALS and METHODS The chemical employed in this study were obtained from S. C. Chimopar S. A., Merck Co., AcrŌs Organic Co, Alfa Aesar Co, Monicolor Co. and S. C. Azur S.A. The colour spectrophotometric data of the two new synthesized direct azo-stilbene dyes were recorded on a Minolta 3200d spectrophotometer and the results were performed by CorobQuality 1.5 program. Four samples which were differentiated by the synthesized direct azo-stilbene dyes and by the white pigment standard (P.W.6) concentrations were layed on a cellusosic substrate. Colours were expressed by the CIELAB analysis of the samples (D65, A

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illuminants, and 10º observer). The colour differences ΔEab* and ΔECMC were calculated confronted by the above mentioned white standard. RESULTS The synthesis of the dyes with the structures Ia and Ib involved two phases: the bisdiazotisation of 4,4'-diaminostilbene-2.2'-disulphonic acid by indirect method, and the coupling reactions of the resultant bis-diazonium salt with the coupling components: 2methyl-N-acetoacetanilide (for dye Ia) and 5-acetoacetylaminobenzimidazolone (for dye Ib)

O

CH3

CH3

C

C

HC O

N

N

CH SO3H

C

CH

N

N

HO3S

O

CH C

O

NH

NH X

X

Z

Z Y

Y

Ia: X=CH3; Y=Z=H Ib: X=H;Y=Z= O

C

NH NH

Structures of the direct azo-stilbene dyes Ia and Ib ΔEab* is based on L *, a*, *b colur differences and was intended to be a single number metric for pass/fail decisions. The human visual system is more sensitive to different kinds of changes and perceives these differences in different magnitudes even though they may have the same calculated difference. For instance, the eye is more sensitive to changes in chroma than changes in lightness. The different color difference equations give weightings in different parts of the color space to better match the differences seen by the human eye. ΔECMC is a single number pass/fail measurement that defines a 3-dimensional tolerancing space. The colours of the obtained samples were expressed by means of the rectangular (L*, a*, b*) and cylindrical (L*, C*, h0) coordinates. The colour differences values calculated by ΔE*ab and ΔECMC formulas were compared. The spectrophotometric results obtained using D65(natural day light), and A (tungsten light) illuminants and the standard 10° observer, are shown in tables 1 for dye Ia and in table 2 for the dye Ib.

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Table 1 The spectrophotometric data of the azo-stilbene dye Ia W

W1

W2

W3

W4

Stand

2%dye

5%dye

8%dye

15%dye

L*

94.57

88.45

83.18

80.39

78.08

a*

-0.25

2.54

5.41

8.01

10.62

b*

1.69

22.20

28.56

33.14

34.17

C*

1.71

22.35

29.06

34.09

35.78



1.72

1.46

1.38

1.33

1.27

Illuminant

D65

ΔEab*/ΔECMC

A

21.59/27.87 29.72/37.07 35.47/43.94

38.01/46.34

L*

94.67

90.13

85.50

83.20

81.21

a*

0.37

5.92

9.17

11.60

13.57

b*

1.50

23.83

31.14

36.59

38.26

C*

1.54

24.55

32.46

38.38

40.59



1.33

1.33

1.28

1.26

1.23

ΔEab*/ΔECMC

23.46/31.37 32.25/42.22 38.59/50.32

41.31/53.38

Table 2 The spectrophotometric data of the azo-stilbene dye Ib W

W1

W2

W3

W4

Stand.

2%dye

5%dye

8%dye

15%dye

L*

94.57

81.41

75.60

70.54

64.52

a*

-0.25

11.91

17.94

20.82

21.95

b*

1.69

16.57

23.51

24.23

24.70

C*

1.71

20.41

29.57

31.95

33.04



1.72

0.95

0.92

0.86

0.84

Illuminant

D65

ΔEab*/ΔECMC

A

23.30/26.23 34.16/38.73 39.11/42.29 43.88/44.20

L*

94.67

83.04

79.08

74.37

68.49

a*

0.37

12.97

18.74

21.44

22.32

b*

1.50

20.73

29.62

31.03

31.81

C*

1.54

24.45

35.05

37.72

38.86



1.33

1.01

1.01

0.97

0.96

ΔEab*/ΔECMC

25.42/31.53 37.03/46.05 41.57/49.89 45.67/51.75

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CONCLUSIONS •

The colour expression of two new symmetric disazo-stilbene direct dyes, synthesized using 4,4'-diaminostilbene-2,2'-disulphonic acid as middle component and 2-methylN-acetoacetanilide and 5-acetoacetylaminobenzimidazolone as coupling components respectively was peformed in the CIELAB colour space



The spectrophotometric data indicate a high colouring power for the studied disazostilbene dyes under the standard illuminants D65 (natural day light), A (tungsten light) and the standard 10º observer respectively

LIST OF REFERENCES [1] Schanda J. (2008), Colorymetry: Understanding the CIE system, ed. Wiley-Interscience, Hoboken

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EXPERIMENTAL STUDY OF THE INTERACTION OF ONE LOCAL ANESTHETIC WITH A CELLULOSE TYPE SUPPORT Simu Georgeta Maria1, Muntean Simona Gabriela2, Grad Maria Elena2 1

"Victor Babeş” University of Medicine and Pharmacy Timişoara, Faculty of Pharmacy, 2-4 P-ta. Eftimie Murgu, 300034 Timişoara, Romania e-mail: GSIMU@YAHOO.COM 2 Institute of Chemistry Timişoara of the Romanian Academy,B-dul. Mihai Viteazul 24,300223 Timişoara, Romania

ABSTRACT The extent of the adsorption of a local anesthetic (Bupivacaine) on a pharmaceutical adsorbent, namely microcrystalline cellulose (MCC) suspended in aqueous solution was investigated spectrophotometrically at three different temperatures. The equilibrium adsorption contact times were determined for all the temperatures and were found around 90 minutes. Adsorption isotherms have been analyzed by the Freundlich and Langmuir models. The obtained results indicated that the Freundlich isotherms presented the highest correlation coefficients, and thus they describe better the adsorption of the studied drug on MCC. INTRODUCTION Adsorption is one of the most important mechanisms of interaction between drugs and excipients due to the fact that the adsorption of a drug onto solid dosage form excipients may influence its characteristics, analytical testing and bioavailability. This matter of fact is of a particularly interest especially for drugs which are normally used in low doses and it is obvious that drug interactions are one of the most important factors that should be considered in any preformulation study [1]. Bupivacaine (RS)-1-butyl-N-(2,6-dimethylphenyl) piperidine-2-carboxamide) is a local anaesthetic drug belonging to the amino-amide group and is commonly marketed under various trade names, including Marcain, Marcaine, Sensorcaine and Vivacaine [2]. Bupivacaine blocks the generation and conduction of nerve impulses. It is commonly used for analgesia by infiltration of surgical incisions. Preemptive use of analgesics (including local anaesthetics used to control post-operative pain), before tissue injury, is recommended to block central sensitization, thus preventing pain or making pain easier to control [3]. Bupivacaine has a longer duration of action than lidocaine, to which it is chemically related approx. 6-8 hours as opposed to 1-2 hours for lidocaine. Duration of action is affected by the concentration of Bupivacaine used and the volume injected. Concentration affects the time for local anaesthesia to occur and the density of the block. Volume determines the area that is infiltrated and therefore anesthetized [4]. Microcrystalline cellulose (MCC) is considered to be as an excellent excipient in the preparation of direct-compressed tablets and, is extensively used in the field of drug formulations [5]. However, few studies were carried-on in order to obtain information about its interaction with drugs. In this area of interest, one could only refer to the adsorption on MCC of some few steroids, phenothiazines, antihistaminics and antibiotics, but the adsorption mechanism is still unclear and of great actuality [6-10]. The aim of this present work was to

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study the adsorption of Bupivacaine on MCC suspended in aqueous solution, at severeal temperatures, in order to obtain more information concerning the interaction of this specific drug with this type of excipient. The basic idea was to find out if the experimental results could be fitted into the classical Langmuir and/or Freundlich adsorption isotherms. MATERIALS and METHODS Bupivacaine hydrochloride (99%) was provided by Fluka, and Microcrystalline cellulose (BCR302-20G) was supplied from Aldrich Sigma. Both reagents were used such as, without further purification. The UV-VIS spectroscopy study was performed using a CECIL CE 7200 spectrophotometer. The analytical wavelenght [nm] used in the spectrophotometric determinations of bupivacaine was 271 nm Adsorption studies A series of stock solutions containing Bupivacaine hydrochloride were prepared in distilled water. The absorbance of the drug solutions was measured at 271 nm in order to obtain a calibration curve, according to Lambert-Beer law. In the first stage, we investigate the time necessary to reach the equilibrium. Further, based on the results from the preliminary experiments, we investigate the extent of adsorption of the drug on MCC. In the case of the preliminary experiments, 10 mL of an initially bupivacaine solution (8×10-5 M) was added into 25 ml volumetric flasks containing 0,2 g (±0,0001) of MCC. were placed. Similarly, 12.5 ml of distilled water was added to equal graded amounts to adsorbents in 25 ml volumetric flask (without drug used as blanks for the absorbance measurements). The mixtures were put in a shaker bath set at different temperatures (ranging from 25, 35 and 40oC (± 1oC)) and were shaken for 12-60 h. At the end, the solutions were filtered by using double filter papers. The final concentrations of the free drug in solution were obtained spectrophotometrically, using the Lambert Beer's plot previously obtained. The preliminary studies indicate that the adsorption equilibrium of Bupivacaine on MCC was attained within 90 mintes. In order to obtain the adsorption isotherms of the studied drug, solutions of different concentrations of Bupivacaine were prepared by serial dilutions in the range of 1x10-5 to 3,2x10-4 mol/L. Adsorbent surface samples of 0.20 g each were weighed and placed in a screw cap bottle, to which 10 mL of the drug solutions were added. The mixtures were shaked in the thermostated shaker at the same temperatures and times as in the preliminary experiments. At the end of the adsorption period, the solutions were filtered and the clear supernatants were analysed spectrophotometrically after appropriate dilutions. The adsorbed amount of the drug was calculated from the concentration in solutions before and after adsorption according to the equation (1): [D ]ad = ([D ]i − [D ]s ) ⋅ V / 1000 ⋅ m (1) where [D]ad is the equilibrium drug concentration on MCC (mmol/g), [D]i and [D]s are the initial and equilibrium concentrations of drug solution(mmol/L), V is the volume of drug solution (L), and m is the amount of MCC sample used (g). Control experiments, in which no drug was added, were performed in parallel, and the filtrate was used as a reference solution. RESULTS In the thermodynamic studies, the results of experimental sorption measurements are usually expressed in the form of equilibrium sorption isotherms. In this, present study, two types of isotherms have been investigated, namely the Langmuir and Freundlich isotherms [11].

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The 17th Int. Symp.on Analytical and Environmental Problems, Szeged, 19 September 2011

The Langmuir equation assumes that there is no interaction between the adsorbed molecules and that the sorption is localized in a monolayer. This model also assume that once a drug molecule occupies a site, no further sorption can take place at this site. Theoretically, therefore, a saturation value is reached, beyond which no further adsorption can take place. The Freundlich equation is an empirical relationship describing the adsorption of solutes from a liquid to a solid surface. The equations for the two types of sorption isotherms are given by equations (2) and (3). (2) [D]ad = K F ⋅ [D]sx [ D] ad =

S f ⋅K L ⋅[ D] s

(3)

1 + K L ⋅ [ D] s

where [D]ad and [D]s are the equilibrium concentration of adsorbed drug, respectively in solution (mmol/L), KF and KL are the Freundlich and Langmuir equilibrium constants, Sf is the saturation value and x is a subunitary power. In order to decide which type of isotherms fits better the sorption experimental data, equations (2) and (3) were linearised giving equations (4) and (5). Further, we plotted the quantities log [D]ad −1 −1 Versus log[D]s for the Freundlich isotherm and [D ]ad Versus [D ]s in the case of Langmuir model. log[D ]ad = log K F + x log[D ]s (4) 1

[D]ad

=

1 1 + S f ⋅ [D]s ⋅K L S f

(5)

The choice of the model which fitted the best with the experimental data was based on the values of the squared regression coefficient (r2), the standard deviation (SE) and the Fisher test (F) which were used as statistical criterions and were computed by linear regression analysis. These results are presented in table 1. Table 1. Statistical results of the adsorbtion of Bupivacaine on MCC at 25, 35 and 40 oC 25oC 35oC 40oC Freundlich Langmuir Freundlich Langmuir Freundlich Langmuir r2 0,989 0,653 0,978 0,546 0,986 0,628 SE 0,004 0,069 0.007 0,102 0,005 0,087 F 1529.108 45,463 1169,453 38,765 1347,629 41,613

[D]ad (x10-4 mmol/g MCC

As it can be seen from the results presented in table 1, the Freundlich isotherm fits better with the experimental results, at all the studied temperatures. The inspection of the experimental results clearly indicate that the adsorption of Bupivacaine on MCC decreased with increasing temperature, showing thus an exothermic nature of the process. In figure 1 is given the adsorption isotherm of Bupivacaine on MCC at 25oC. 12 10 8 6 4 2 0 0

1

2

3

4 -4

[D]s (x10 mol/L Figure 1. Adsorption isotherm of Bupivacaine on MCC at 25oC

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The 17th Int. Symp.on Analytical and Environmental Problems, Szeged, 19 September 2011

The general shapes of the drug’s adsorption on MCC at the others studied temperatures are very similar. One could consider that the extent to which the studied drug’s adsorption capacity decreases with increasing temperature might be attributed to the change in the surface properties of the adsorbent, as well as to the solubility of the adsorbate species. CONCLUSIONS • The adsorption of Bupivacaine hydrochloride on MCC from aqueous solutions is a function of initial drug concentration, temperature and contact time. • Adsorption isotherm of the drug under study on MCC obeyed Freundlich isotherm as the adsorption increases with increasing the concentration at equilibrium. This result indicated the surface heterogeneity leading to different adsorption force from site and different affinities toward drug molecule. LIST OF REFERENCES [1]

Al-Nimry S., Assaf S., Jalal I., Najib N. (1997). Adsorption of ketotifen onto some pharmaceutical excipients. Int. J. Pharm. 149, p. 115-121. [2] Lagan G., McClure H. A. (2004). Review of local anaesthetic agents. Current Anaesthesia & Critical Care. 15. p. 247-254. [3] Boogaerts J., Declercq A., Lafont N., Benameur H., Akodad E. M., Dupont J. C., Legros F. J. (1993). Toxicity of Bupivacaine encapsulated into liposomes and injected intravenously: comparison with plain solutions. Anesthesia and Analgesia, 76(3). P. 553-555. [4] Shafford H.I., Lascelles B. D. X., Hellyer P. W. (2001) Preemptive analgesia: Managing pain before it begins. Veterinary Medicine. 96, p. 478-492. [5] Sun C. (2005). True density of microcrystalline cellulose. J. Pharm. Sci. 94. P. 21322134. [6] Okada S., Nakahara H., Isaka H. (1987). Adsorption of drugs on microcrystalline cellulose suspended in aqueous solutions. Chem.Pharm.Bull. 35. p. 761-768. [7] Steele D., Edge S., Tobyn M., Moreton R., Staniforth J. (2003). Adsorption of amine drug onto microcrystalline cellulose and silified microcrystalline cellulose samples. Drug Dev. Ind. Pharm. 29. p. 475-487. [8] Reem A. (2010). Adsorption – Desorption Isotherm of One of Antidibetic. Eur. J. Sci. Res. 40(4). p. 580-588. [9] Crowley P., Martini L. G. (2001), Drug-excipient interactions, Pharm Tech Europe. 13(3). p. 26-34. [10] Muratova S. A., Burkhanova N. D., Yagai S. M., Nikonovich G. V., Pulatova K. H., Rashidova S. (2002). Studying interactions in microcrystalline-drug systems. Pharm Chem. J. 36, p. 619-621. [11] Adamson A. W. (1967). Physical Chemistry of Surfaces. Wiley inters. New York p. 397-429.

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SYNTHESIS OF TRIPODAL CYCLOTRIVERATRYLENE (CTV) DERIVATIVES AS SCAFFOLDS FOR BINDING SUGARS Cristian Neanua, Eugen Şişub a

Romanian Academy - Timişoara Institute of Chemistry, Bd. Mihai Viteazul no 24, RO300223, Timişoara, România, b ”Victor Babeş” University of Medicine and Pharmacy Timişoara, Eftimie Murgu Sq. No.2, RO-300041, Timişoara, România e-mail: cristi@acad-icht.tm.edu.ro INTRODUCTION In recent years, significant progress has been made in the area of synthetic or artificial receptors containing two binding arms, which have been often designated as tweezers-like synthetic receptors.[1,2] To increase diversity, possibly affinity, selectivity, and other properties, we are interested in the development of artificial receptors containing three binding arms, that is, tripodal molecules containing ultimately three different sites of interaction. Still, the number of suitable molecules to serve as suitable scaffolds for attachment of three binding sites is very limited. Noteworthy examples in the literature include steroids,[3] diverse macrocycles,[4] Kemp’s triacid,[5] amidopyridine,[6] and hexasubstituted benzenes.[7] We have been particularly interested in the cyclotriveratrylene (CTV) scaffold. Here, we describe the otaining of deprotected CTV for the construction of versatile CTVscaffold derivatives as tripodal artificial synthetic receptor. RESULTS A completely and partially deprotected tripodal cyclotriveratrylene (CTV)-based scaffolds intermediate (compound 04, Figure 2) have been prepared. The CTV(O-All)3, (compound 03, Figure 1) (as intermediate compound in obtaining CTVscaffold derivatives), was synthesized in two steps on a multigram scale starting from vanillyl alcohol.[8]

Figure 1. CTV(O-Allyl)3 synthesis

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The 17th Int. Symp. on Analytical and Environmental Problems, Szeged, 19 September 2011

O MeO

O

OMe

OMe O

Pd/c 10% HClO4 70%, Dioxan:EtOH (2:1), 20h, 600C

(O-All) OH MeO

(O-All) HO

OMe

OMe OH (O-All)

mixture of mono, di, tri CTV(OH)

CTV(O-Allyl)3 [03]

Figure 2. CTV(OH)3 synthesis

[04]

EQUIPMENT AND METHODS All reagents were purchased from commercial sources and used without further purification. When was needed, anhydrous solvents were used. NMR spectra were recorded on a Varian 300 MHz spectrometer against the line of the solvent (CDCl3). Chemical shifts are given in ppm. The TLC (thin layer chromatography) analysis was performed on Kieselgel Merck plates with fluorescence indicator. Column chromatography was carried out using 220-400 mesh silica (Aldrich). Visualization of the chromatograms was accomplished with a UV lamp. CONCLUSIONS • The CTV(O-Allyl)3 deprotection reaction has been tried by few methods, those with Pd/c 10%, HClO4 (70%) giving the best results. • The CTV deprotection allow attaching later a number of natural amino compounds like (aminoacids, peptides, proteins) and non-natural amino compounds like (dyes, synthetic porphyrins or polyamides). • Obtaining quantitative results in the deprotection reaction is still a not solved problem and is now under study. LIST OF REFERENCES [1] (a) Chen, C. W.; Whitlock, H. W., Jr. J. Am. Chem. Soc. 1978, 100, 4921-4922. (b) Zimmerman, S. C.; Wu, W.; Zeng, Z. J. Am. Chem. Soc. 1991, 113, 196-201. For a review, see: (c) Zimmerman, S. C. Top. Curr. Chem. 1993, 165, 71-102. [2] (a) Jensen, K. B.; Braxmeier, T. M.; Demarcus, M.; Frey, J. G.; Kilburn, J. K. Chem. Eur. J. 2002, 8, 1300-1309. (b) Conza, M.; Wennermers, H. J. Org. Chem. 2002, 67, 2696- 2698. (c) Braxmeier, T.; Demarcus, M.; Fessmann, T.; McAteer, S.; Kilburn, J. D. Chem. Eur. J. 2001, 7, 1889- 1898. (d) Botana, E.; Ongeri, S.; Ariezo, R.; Demarcus, M.; Frey, J. G.; Piarulli, U.; Potenza, D.; Gennari, C.; Kilburn, J. D. Chem. Commun. 2001, 1358-1359.

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[3] (a) Siracusa, L.; Hurley, F. M.; Dresen, S.; Lawles, L. J.; Pe´rez-Pa´yan, M. N.; Davis, A. P. Org. Lett. 2002, 4, 4639-4642. (b) Davis, A. P.; Perry, J. J.; Williams, R. P. J. Am. Chem. Soc. 1997, 119, 1793-1794. [4] (a) Choi, H.-J.; Park, Y. S.; Yun, S. H.; Kim, H.-S.; Cho, C. S.; Ko, K.; Anh, K. H. Org. Lett. 2002, 4, 795-798. (b) Choi, K.; Hamilton, A. D. J. Am. Chem. Soc. 2001, 123, 2456-2459. (c) Lo¨wik, D. W. P. M.; Lowe, C. R. Tetrahedron Lett. 2000, 41, 1837-1840 [5] Kocis, P.; Issakova, O.; Sepetov, N. F.; Lebl, M. Tetrahedron Lett. 1995, 36, 66236626. [6] Ballester, P.; Capo; M.; Costa, A.; Deya, P. M.; Gomila, R.; Decken, A.; Deslongchamps, G. J. Org. Chem. 2002, 67, 8832-8841. [7] (a) Hennrich, G.; Lynch, V. M.; Anslyn, E. V. Chem. Eur. J. 2002, 8, 2274-2278. (b) Hennrich, G.; Anslyn, E. V.Chem. Eur. J. 2002, 8, 2219-2224. [8] Cancelli, A.; Gabard, J.; Collet, A. J. Chem. Soc., Chem. Commun. 1983, 122-123.

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SYNTHESIS OF ULTRAFINE GAHNITE (ZnAl2O4) NANOCRYSTALS BY COPRECIPITATION METHOD Miron Iasmina1,2, Ursu Daniel Horatiu1,2, Grozescu Ioan1,2 1

2

Politehnica University of Timisoara, Romania National Institute for Research and Development in Electrochemistry and Condensed Matter Timisoara, Romania E-mail: mironiasmina@gmail.com

ABSTRACT Nanocrystalline zinc aluminate ZnAl2O4 has been obtained by coprecipitation method at two different temperatures (800°C and 900°C). The precursors used in coprecipitation synthesis of ZnAl2O4 were zinc nitrate hexahydrate and aluminum nitrate nonahydrate. As a basic source sodium hydroxide was used. The obtained samples were analyzed by X-ray diffraction (XRD) and by energy dispersive spectroscopy (EDAX). Optical properties of nanocrystalline zinc aluminate were also determined by UV/VIS/NIR spectroscopy. The band gap for sample obtained at 800°C was 3,88 eV while for sample obtained at 900°C was 3,97 eV. Keywords: zinc aluminate, coprecipitation, spinels INTRODUCTION Zinc aluminate (ZnAl2O4) with a cubic, normal crystal structure is widely used as ceramic, electronic and catalytic material [1,2]. The normal spinel ZnAl2O4 has general formula AB2O4, where A and B stands for divalent and trivalent ions, respectively. In this structure, unit cell contains 8 tetrahedral cations (A sites), 16 octahedral cations (B sites) and 32 oxygen anions within the close-packed face-centered cubic unit cell with Fd3m space group symmetry. In normal spinel ZnAl2O4 structure, the divalent cations Zn2+ are at the A sites and the trivalent cations Al3+ at the B sites. The band gap of ZnAl2O4 nanocrystals is 3.8 – 3.9 eV [3,4]. In the literature, many synthesis methods for the obtaining of ZnAl2O4 have been described, such as: coprecipitation [5], hydrothermal method [6,7], sol–gel [8,9], microwave assisted hydrothermal method [10]. Herein, nanocrystalline zinc aluminate (ZnAl2O4) particles with a spinel structure were prepared by coprecipitation method at two different temperatures (800°C and 900°C) using zinc nitrate hexahydrate and aluminum nitrate nonahydrate as precursors and sodium hydroxide as the basic source. MATERIALS AND METHODS ZnAl2O4 powders were prepared by coprecipitation method. As precursors Zn(NO3)2·6H2O and Al(NO3)3·9H2O were used. The precursors were mixed in distilled water, then, the appropriate amount of sodium hydroxide solution was added. The mixture was stirred at room temperature for few hours. The resulting suspension was filtrated and washed many times with distilled water and ethylic alcohol, then dried in an oven at 80°C for 6 hours. After drying resulting powders were heated at 800°C and 900°C for 5h. The characterization of the obtained materials was achieved by X-ray diffraction (XRD) using an X’pert Pro MPD X-ray diffractometer, with monochromatic Cu Kα (λ = 1.5418 Ǻ) incident radiation and by energy

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dispersive spectroscopy (EDAX) using an scanning electron microscopy (SEM + EDAX; Model INSPECT S). UV/VIS/NIR measurement was carried out using an UV/VIS/NIR spectrophotometer (Model Lambda 950). RESULTS X-ray diffraction patterns of the powder samples obtained by coprecipitation method at two different temperatures (800°C and 900°C) are shown in Figure 1 (a) and (b). The observed peaks can be indexed as (111), (220), (311), (400), (331), (422), (511), (440), (620) and (533) crystal planes of the cubic crystalline structure of ZnAl2O4, respectively, in accordance with the standard JCPDS card of cubic spinel-type ZnAl2O4 (JCPDS no. 05-0669). X-ray diffraction patterns showed a single phase ZnAl2O4. The average crystallite size was calculated using Schererr’s equation. It was found that average crystallite size increase from 24 nm (for sample heated at 800°C for 5h) to 28 nm (for sample heated at 900°C for 5h). For both samples the cubic lattice parameter was calculated from X-ray diffraction patterns. It was found that this parameter increases with the temperature, as a = 8,0725 Å for sample heated at 800°C for 5h and a = 8,0786 Å for sample heated at 900°C for 5h.

Figure 1 XRD patterns of ZnAl2O4 samples obtained by coprecipitation method: a) 800°C and b) 900°C To analyze chemical composition of obtained zinc aluminate nanoparticles energy dispersive X-ray analysis (EDAX) was performed. A typical EDAX spectrum of ZnAl2O4 samples obtained by coprecipitation method is presented in Figure 2 (a) and (b). EDAX measurements were performed in different points of the powders and then an average of the results was made. The results confirmed the uniformity and the closely stoichiometric composition with the precursor material.

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(a) (b) Figure 2 The qualitative EDAX analysis of ZnAl2O4 samples obtained by coprecipitation method: a) 800°C and b) 900°C The absorbance was calculated from the diffuse reflectance spectrum using Kubelka–Munk equation. The optical absorbance spectrum (Figure 3) of ZnAl2O4 is detected in the 250-400 nm region at room temperature.

Figure 3 Absorbance spectrum of ZnAl2O4 samples obtained by coprecipitation method: a) 800°C and b) 900°C From absorbance spectrum we plotted {(k s )(hν )} vs. hν (energy) (Figure 4), where k denotes absorption coefficient, s is scattering coefficient and hν is the photon energy. 2

Figure 4 Plot of {(k s )(hν )} vs. hν (energy) of ZnAl2O4 samples obtained by coprecipitation method: a) 800°C and b) 900°C 2

The band gap of ZnAl2O4 were determined from the absorbance spectra. The band gap value depends strongly by temperature used. One can see that the band gap for sample obtained at 800°C is 3,88 eV and for sample obtained at 900°C is 3,97 eV.

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CONCLUSIONS • • • •

In this research, ZnAl2O4 nanoparticles were successfully prepared by coprecipitation method at different temperatures using zinc nitrate hexahydrate and aluminum nitrate nonahydrate as precursors. From X-ray diffraction, one can see that ZnAl2O4 spinel was single phase crystallized and the particle size depends strongly by heating temperature. EDAX measurements confirmed the uniformity and the closely stoichiometric composition with the precursor material. Morevover, the band gap for sample obtained at 800°C was 3,88 eV while for sample obtained at 900°C was 3,97 eV.

ACKNOWLEDGEMENT

This work was partially supported by the strategic grant POSDRU/88/1.5/S/50783, Project ID50783 (2009), co-financed by the European Social Fund – Investing in People, within the Sectorial Operational Programme Human Resources Development 2007-2013. LIST OF REFENCES

[1] Sampath S.K., Kandive D.G., Pandey R. (1999). Electronic structure of spinel oxides: zinc aluminate and zinc gallate, J. Phys.: Condens. Matt. 11, p. 3635 [2] S. Mathur, M. Veith, M. Haas, H. Shen, N. Lecerf, V. Huch, S. Hüfner, R. Haberkorn, H.P. Beck, M. Jilavi (2001). Single-Source Sol-Gel Synthesis of Nanocrystalline ZnAl2O4: Structural and Optical Properties, J. Am. Ceram. Soc. 84, p. 1921 [3] Shen S.C., Hidajat K., Yu L.E., Kawi S. (2004). Simple Hydrothermal Synthesis of Nanostructured and Nanorod Zn–Al Complex Oxides as Novel Nanocatalysts, Adv. Mater. 16, p. 541-545 [4] Kumar K., Ramamoorthy K., Koinkar P.M., Chandramohan R., Sankaranarayanan K. (2007). A novel way of modifying nano grain size by solution concentration in the growth of ZnAl2O4 thin films, J. Nanopart. Res. 9, p. 331–335 [5] Ciupina V., Carazeanu I., Prodan G. (2004). Characterization of ZnAl2O4 nanocrystals prepared by coprecipitation and microemulsion techniques, Journal of Optoelectronics and Advanced Materials 6, p. 1317 – 1322 [6] Chen X.Y., Ma C., Zhang Z.J., Wang B.N. (2008). Ultrafine gahnite (ZnAl2O4) nanocrystals: Hydrothermal synthesis and photoluminescent properties, Materials Science and Engineering B 151, p. 224–230 [7] Yang C.-C., Chen S.-Y., Cheng S.-Y. (2004). Synthesis and physical characteristics of ZnAl2O4 nanocrystalline and ZnAl2O4/Eu core-shell structure via hydrothermal route, Powder Technology 148, p. 3– 6 [8] Duan X., Yuan D., Wang X., Xu H. (2005). Synthesis and Characterization of Nanocrystalline Zinc Aluminum Spinel by a New Sol-Gel Method, Journal of Sol-Gel Science and Technology 35, p. 221–224 [9] Wu Y., Du J., Choy K.-L., Hench L.L., Guo J. (2005). Formation of interconnected microstructural ZnAl2O4 films prepared by sol–gel method, Thin Solid Films 472, p. 150– 156 [10] Zawadzki M. (2006). Synthesis of nanosized and microporous zinc aluminate spinel by microwave assisted hydrothermal method (microwave–hydrothermal synthesis of ZnAl2O4) , Solid State Sciences 8, p. 14–18

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COAGULATION CHARACTERISTICS OF ELECTROCHEMICALLY PREPARED POLYALUMINIUM CHLORIDE ON HUMIC ACID REMOVAL FROM WATER Adina Păcală*, Ilie Vlaicu*, Ciprian Radovan** * Water Treatment Company - AQUATIM, 11A Gh.Lazar Street, 300081 Timisoara, Romania. ** West University of Timisoara, Faculty of Chemistry, Biology and Geography, Department of Chemistry, 16A Pestalozzi Street , 300115 Timisoara, Romania.

e-mail: adina.pacala@aquatim.ro ABSTRACT The treatment of surface natural water for drinking water production goes through the degradation of humic substances. The increasing demand of more efficient coagulation water treatment, especially regarding the removal of natural organic matter (NOM), has lead to the development of a new category of coagulants, the pre-polymerised inorganic coagulants, such as polyaluminium chloride (PAC). An alternative preparation procedure for PAC (prehydrolyzed aluminium chloride with general formula Alm(OH)nCl3n-m) is presented in this paper. Using the principles of coagulant preparation and of the electrolysis process, the proposed procedure is based on the use a new method for the preparation of electrochemically obtained PAC (E-PAC) in an electrochemical reactor, equipped with plain-plate Al anodes and stainless steel cathodes, and AlCl3 aqueous solution as electrolyte, applied with successfully in our laboratory. Coagulation behaviors of E-PAC and conventional coagulants as alum and commercial product PAC were compared, using the so-called „Jar test" procedure, in accordance with water treatment standards, to remove humic acid (HA) from deionized water with addition of 1mg/L of humic acid (commercial HA powder), selected for this study, due to the fact that it is a principal component of humic substances, which are typically the major component of NOM in water supplies. As part of the applied procedures, the level of residual turbidity, the amount of total organic carbon, the UV-254 absorbance and colour were evaluated, in oerder to assess the efficiency of the coagulation process in all situations (PAC, E-PAC and alum as coagulants). The results suggest than the electrochemically obtained E-PAC can be alternatively produced by electrolysis process easily controlled, resulting a product with better properties than the commercial PAC used for comparison to remove humic acid from synthetic water. Keywords: Coagulation, Drinking water treatment, Electrochemical Polyaluminiumchloride (E-PAC), Humic acid 1. INTRODUCTION The coagulation process typically includes promoting the interaction of particles to form larger aggregates. It is an essential component of conventional water treatment systems in which the processes of coagulation, sedimentation, filtration, and disinfection are combined to clarify the water for removal of natural organic material (NOM) and to remove and inactivate microbiological contaminants. Optimizing natural organic matter (NOM) removal by coagulation is a crucial challenge in drinking water treatment. Indeed, the organic material remaining within the clarified water is involved in most problems encountered in the treatment process, such as

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formation of carcinogenic chlorinated organic compounds during disinfection, taste and odor of the finished water, and biological regrowth in the distribution networks [2]. NOM consists of a huge variety of organic compounds including simple sugars, amino acids, organic acids, proteins and many others. In most cases, the so-called ‘humic substances’ are major components of aquatic NOM. They are classified according to their aqueous solubility, with fulvic acids being more soluble than humic acids [1]. It has long been known that humic substances can be effectively removed from water by hydrolysing coagulants and there have been many studies on this subject [1,2,3,6,7] Enhanced coagulation has been proposed as the best available technology for NOM removal, and the regulation for percentage removal of NOM expressed in total organic carbon (TOC) was set up based on raw water quality. The most common coagulant used in water treatment is alum Al2(SO4)314-H2O, due to its effectiveness in treating a wide range of water types and relatively low cost. The use of preformed polymerized forms of Al has become more common as alternative coagulants, with polyaluminum chloride (PAC). These coagulants have the advantage of being more effective at lower temperatures and a broader pH range than alum. PAC contains stable preformed aluminum species that are thought to be more effective at charge neutralization than alum due to a higher charge density. The primary polymeric species is the tridecameric polymer Al13O4(OH)24(H2O)7+ referred to as the Al13 polymer [3]. At present, the commercial PAC solutions contain relative low content of Al13 (<50%) and there are still some limitations for other preparation methods to increase the Al13 content at high basicity [8]. In this paper, a new method for producing polyaluminium chloride PAC-electrolysis process (E-PAC) is applied, using the principle of coagulant preparation and of the electrolysis process [4,5,6]. Particularly, the purpose was to synthesize a product with similar properties to commercially available PAC. The aim of this work is to characterize the E-PAC prepared in optimum conditions in our laboratory by electrolysis process [6]. Its coagulation performance was evaluated in laboratory scale, using the so-called „Jar test" procedure, in accordance with water treatments standards, to remove humic acid (HA) from deionized water with addition of 1mg/L of humic acid (commercial HA powder), selected for this study due to the fact that is a principal component of humic substances, which are typically the major component of NOM in water supplies. Since we aim in particular to improve the treatment of Bega River as raw water source for potable utility of Timisoara town (Romania), we compared E-PAC with the performance of a commercially available PAC solution and classical aluminium sulphate (alum). 2. MATERIALS AND METHODS 2.1. Coagulants and water samples All chemical reagents used were analytically pure chemicals. Deionized water with conductivity 2.54 μS/cm was used in preparing all the solutions. For comparison purposes, commercially available PAC (8.8 % Al2O3, basicity 65, density 1.22 kg/dm3) was a a Donau Chemie product (Austria). Alum stock solution was prepared from liquid aluminium sulphate (approximately 7.5% as Al2O3) obtained from a local Bega water treatment plant. The synthetic model water consisted of a stock HA solution prepared by adding commercial Humic acid powder (HA, Agros Organics Company, Germany), used as the model organic matter, into deionized water. After that, this stock solution was stirred for 5 min., at 300 rpm and filtered for removing residual non-dissolved HA powder. 2.2. Electrochemical preparation of E-PAC

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The electrochemical reactor (ECR) for E-PAC preparation [4,5] consisted on a D.C. Power Supply (HY 3000D, China), an electrolyzer made out of organic glass (rectangular size 76 x 51 x 70mm) equipped with 6 parallel plain-plate electrodes, 3 anodes and 3 cathodes disposed in a mono-polar arrangement with 10 mm anode-cathode distance. Three sheets of Al (95 x 50 mm) were used as anodes while the cathodes were three sheets of stainless steel plates (95 x 50 mm). The system is completed by the electrolyte (200ml aqueous solution AlCl3 0.5M) and stirring apparatus (IKA, Germany), with degree of agitation selected of 600 rpm. An ammeter and a voltmeter were used for electrical characteristics control. Electrolysis was carried out in galvanostatic conditions at optimum conditions, selected from our previous studies, respectively current density of 1.15 A dm-2, electrolysis time of 2 hours, current intensity of 1.5 A [6]. 2.3. Experimental and analytical methods Coagulation experiments were carried out at room temperature using jar test on a sixpaddle gang stirrer, equipment manufactured by Velp Scientifica (Model FC6S, Italy). The 800mL working HA solution was added into the1000mL beaker. A measured amount of coagulant was added by a calibrated pipette (Multipette stream Electronic hand dispenser, Eppendorf, Germany) into the working HA solution under rapid stirring. The HA solution was stirred rapidly at 150 rpm for 2 min after coagulant dosing, followed by slow stirring at 45 rpm for 15 min, which compares to current plant conditions at the Timisoara Waterworks. For 30 min after settling, supernatants were collected to measure residual turbidity using a Turbidimeter (HACH 2100N, USA). Total organic carbon (TOC) was analyzed after filtration through a 0.45 mm membrane and were determined using a TOC Analyzer (TOC-V CPH, SHIMADZU, Germany). pH and conductivity were determined on a laboratory multiparameter analyser (Consort C863, Consort, Belgium). Colour in Hazen units was measuring using a photometer SQ 118 Merck (Germany). The absorbance at 254 nm (due to the Natural Organic Matter/NOM content) was measured with a Spectrofotometru UV-VIS (UV-VIZ T90+, PG Instruments Ltd, SUA), using a 1 cm path length quartz cuvette. 3. RESULTS AND DISCUSSION The coagulation behavior of the electrochemical PAC, obtained in our laboratory, conventionnaly named electrochemical - PAC (E-PAC), was evaluated in the (model) humic sample (with relatively low HA concentration level as 1mgHA/L), simulating contaminated surface water (see the previous §2.1) and compared with the coagulation behavior of a commercial PAC and with the traditionally applied coagulant aluminum sulphate (”alum”), used today in Bega water treatment process. The applied coagulant doses were the same 1mg Al/L, for all three coagulants compared. Table 1 demonstrates the coagulation performance of all three coagulants. Removal of residual turbidity, conductivity and colour, the variation of pH, absorbance at 254 nm, TOC and NPOC of the suspensions after the addition of coagulant are presented. The mechanisms to explain the coagulation of humic substances include charge neutralization, precipitation, bridge-aggregation, adsorption and sweep-flocculation [7]. For turbidity removal, polymer bridging plays an important role, which is facilitated by high molecular weight polymers with relatively low charge density. For NOM removal, charge neutralization plays a dominant role.

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Table 1. Water quality parameters of raw water and treated water with aluminium sulphate, PAC and E-PAC PARAMETER,

RAW

ALUMINIUM

PAC

E - PAC

UNIT

WATER

SULFATE

Turbidity, NTU

2.08

1.29

1.11

1.10

pH

5.26

4.96

5.42

4.99

TOC, mgC/L

1.124

0.888

0.759

0.268

Colour, °Hazen

8

6

7

6

UV-254, m-1

0.046

0.027

0.038

0.041

Conductivity, μS/cm

8.77

24.6

20

61.3

Generally, aqueous NOM is negatively charged and the coagulant demand for neutralizing the negative charge is much higher than the one for neutralizing the charge of mineral particles [4,5].

Figure 1. TOC results of raw water and treated water(1) with aluminium sulphate(2), PAC(3) and E-PAC(4). Therefore, E-PAC proved to be the most efficient coagulant in terms of TOC and turbidity removal (Fig.1) on humic acid from synthetic water. Scan Spectrum Curve for domaine 200-350 nm wavelength have been rendered with UV-254 nm absorbency, as shown in Fig.2. E-PAC seems to exhibit better coagulation performance than PAC and alum, especially in very low coagulant dose (e.g. 1 mg Al/L).The superiority of E-PAC can be attributed to the higher Al13 content, than the respective values of PAC.

Figure 2. UV absorbency spectrum curve This is an indication of higher coagulant charge, resulting in more effective charge neutralization, colloids destabilization and consequently, in better coagulation performance.

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4. CONCLUSIONS ► The results suggest that the electrochemically obtained E-PAC can be alternatively produced by electrolysis process easily controlled. ► Due to their improved properties, E-PAC show superior coagulation performance than the commercial PAC used for comparison, when applied for the treatment on humic acid removal from synthetic water. ► Our study suggests that the functional groups involved in the aggregation of humic substances change with the positively charged coagulants species. ► Optimum data regarding residual turbidity and concentration of organics compounds (TOC) were obtained when E-PAC has been utilized as coagulant. ► It can be estimated that the electrochemical production of polyaluminium chloride might be developed at a larger scale, to be used in surface water treatment for potabilization, but more research efforts can be devoted to this purpose. 5. REFERENCES [1] Duan J., Gregory J., (2003), “Coagulation by hydrolysing metal salts”, Advances in Colloid and Interface Science, 100 –102, 475–502. [2] Kaspard V., et.al, (2006), “Fate of coagulant species and conformational effects during the aggregation of a model of a humic substance with Al13 polycations”, Water Research, 40, 1965-1974. [3] McCurdy K., Carlson K., Gregory D., (2004), “Floc morphology and cyclic shearing recovery: comparison of alum and polyaluminum chloride coagulants ”, Water Research, 38, 486-494. [4] Păcală A., Vlaicu I., Radovan C., (2009), “Application of several aluminium prehydrolysed coagulants in surface water treatment for potabilization”, Environ. Eng. and Manag. Journal, vol.8, 6, 1371-1376. [5] Păcală A., Vlaicu I., Anghel M., Radovan C., (2010), “Study on coagulation properties and efficiency of polyaluminum chloride (E-PAC) prepared by electrolysis process”, Annals of University Ovidius of Constanta, 497-502. [6] Păcală A., (2010), “Contributions to surface water treatment for drinking purpose by using electrochemically generated polyaluminium chloride, PhD Thesis, West University of Timisoara. [7] Zhang P., et.al, (2008), “Coagulation characteristics of polyaluminum chlorides PAC-Al30 on humic acid removal from water”, Separation and Purification Technology, 63, 642-647. [8] Zouboulis A.I., Tzoupanos N., “Alternative cost-effective preparation method of polyaluminium chloride (PAC) coagulant agent: Characterization and comparative application for water/wastewater treatment”, Desalination, 250 (2010) 339–344.

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INVENTORY OF MEAT INDUSTRY POLLUTERS IN VOJVODINA REGION 1

Dušan Milovanović, 2Milorad Miloradov, 1Maja Djogo, 1Ivana Mihajlović, 1Jelena Radonić, 1Maja Turk Sekulić, 1Srdjan Kovačević 1

Faculty of Technical Sciences, University of Novi Sad, Novi Sad, Serbia 2 Academy of Sciences and Arts of Vojvodina, Novi Sad, Serbia e-mail: dusanmilovanovic@uns.ac.rs

ABSTRACT Inventory of Polluters is the register of information and data on environmental polluters and represents a major starting point for identifying and monitoring of pollution sources. One of the objectives of the National project of the Ministry of Education and Science no 46009: Improvement and development of hygienic and technological procedures in production of animal originating foodstuffs with the aim of producing high-quality and safe products competitive on the global market, is to establish the Inventory of Polluters from the meat industry acquiring all the data required by the Serbian legislation. The meat industry sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global. Inventory of Polluters will include the information and data from polluters identified on the territory of AP Vojvodina from the meat industry sector. According to the obtained results, the total number of potential water pollutants within this sector totals up to 94 legal entities. Keywords: Inventory of Polluters, Meat industry, Water pollution INTRODUCTION Cadaster represents the integral part of the environmental protection information system of the Republic of Serbia, managed by the Environmental Protection Agency in accordance with the legislation and it contains data on pollution of air, water and generation and management of waste from point sources and from settlements that represent diffuse source. Cadaster contains data on sources, types, amounts, method and place of discharge of polluting substances into air and water, as well as on amounts, type, content and the method for treatment and disposal of waste. Certain phrases have following meaning: Polluter is legal entity or natural person who through its activity or inactivity pollutes the environment; Diffuse source is pollution source emitting polluting substances without specifically determined discharge location; Discharge spot is the place for discharge of waste gases, waste water or disposal of generated waste from the plant into the environment; Plant is independent polluter or particular technological system within the polluter, located on geographically determined place with defined discharge spot of waste water, waste gases and generated waste; Point source is source of polluting substances with defined location from one discharge spot (chimney, cannel, drain, etc), several discharge spots connected on one common spot and the location of waste generation. Cadaster is compiled based on the data submitted by the polluters in different industrial sectors. Besides these industrial polluters, especially for Cadaster following entities also submit required data: 1. Municipal, public utility companies – the quality of discharged water from sewage system for each discharge spot, before mixing with the water from the recipient;

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2. Polluters generating hazardous waste in its plants, disregarding the type of industrial activities, capacities and average number of employers in the reporting year; 3. Medical and vet institutions – generated waste; 4. Municipal, public utility companies collecting the waste from the municipalities (municipal waste); 5. Companies and other legal entities collecting and transporting the waste, other than municipal waste; 6. Companies and other legal entities treating the waste; 7. Companies and other legal entities importing the waste for own needs for further trade, disregarding the type of industrial activities. MEAT INDUSTRY SECTOR The meat industry sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global. Meat industry is one of the major causes of the world's most pressing environmental problems, including global warming, land degradation, air and water pollution, and loss of biodiversity. Using a methodology that considers the entire commodity chain, it estimates that meat industry is responsible for 18 percent of greenhouse gas emissions. It accounts for nine percent of anthropogenic carbon dioxide emissions, most of it due to expansion of pastures and arable land for feed crops. It generates even bigger shares of emissions of other gases with greater potential to warm the atmosphere: as much as 37 percent of anthropogenic methane, mostly from enteric fermentation by ruminants, and 65 percent of anthropogenic nitrous oxide, mostly