Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1985. / Includes bibliographical references (leaves 213-218).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 139-145). Also available via the Internet.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.

<p>Osnovni cilj teze bio je doprinos poznavanju prisustva pesticida u površinskim i podzemnim vodama u Srbiji, kao i mehanizama rasprostiranja podzemnom vodom. Korišćeni su rezultati sedmogodišnje kampanje analize kvaliteta površinske vode i korespodentnih punktova za zahvatanje podzemne vode za četiri velike reke u Srbiji: Dunav, Savu, Tisu i Veliku Moravu. Pored sistematizacije i analize podataka o izvršenim analizama na pesticide voda reka i podzemnih voda, urađena su usmerena istraživanja koja se odnose na mehanizme i intenzitet sorbiranja, laboratorijska ispitivanja i terenski ogled. Rezultati ispitivanja i analiza su obrađeni numeričkim modelima.</p> / <p>The main aim of the thesis was to contribute to the knowledge of the presence<br />of pesticides in surface and groundwaters in Serbia, as well as transport<br />mechanisms in groundwater. The results of a seven-year analysis of the<br />quality of surface waters and correspondent points for groundwater<br />abstraction for the four major rivers in Serbia were used: Danube, Sava, Tisa<br />and Velika Morava. In addition to systematization and analysis of data from<br />campaigns carried out for the presence of pesticides in river water and<br />groundwater, targeted research related to the mechanisms and intensity of<br />sorption was implemented that consisted of laboratory and field experiment.<br />The results of experiments and analyzes were processed by numerical<br />models.</p>

Thesis (M. Tech. - Dept. of Chemistry, Faculty of Applied and Computer Sciences) -- Vaal University of Technology, 2010 / The increased production and application of pesticides for agricultural and non-agricultural purposes has caused the pollution of air, soil, ground and surface water. This has a negative impact on the environment as well as human health due to direct exposure or through residues in food and drinking water. The continuous monitoring of pesticides residues in environmental samples has great importance and demands high efficiency, unique selectivity and high sensitivity techniques. Gas chromatography and high performance liquid chromatography have been established for years as the techniques for the analysis of pesticides residues. The dissertation deals with the qualitative and quantitative determination of selected pesticides in the Southern Gauteng region using Liquid- liquid extraction solid-phase extraction, high performance liquid chromatography, gas chromatography equipped with electron capture detector and gas chromatography mass spectrometry. Liquid-liquid extraction and solid-phase extraction using dichloromethane, hexane and ethyl acetate as the extracting solvent were optimized and evaluated for the determination of pesticides in surface water in the Southern Gauteng region. From the developed method the techniques were applied to water samples taken from different rivers selected namely: Zuikerbosch, Rand Water barrage and Kliprivier for sampling. Dichloromethane was used as a solvent in this study since a recovery test was done between dichloromethane, Ethyl acetate and n-hexane. The percentage recovery test for 4,4-DDT, 4,4-DDE, 2,4-DDD and Endosulfan 1 & 2 ranged from 89.9% -97.3% for dichloromethane, 87.3%-96.8% for hexane 88.4%-97.1% for ethyl acetate. The extracts obtained were subjected to column chromatography for clean up. Thereafter 1µl of the cleaned extracts were injected into the Gas chromatography equipped with an electron capture detector. Organochlorines 4,4-DDT and its metabolites, Organophosphate Chlorypyriphos and carbamates were detected using Gas chromatography electron capture, Gas chromatography mass spectrometry and high performance liquid chromatography.