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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

The political ecology of pesticide use in developing countries : dilemmas in the banana sector of Costa Rica

Thrupp, Lori Ann January 1988 (has links)
No description available.
82

Analytical methods and instrumentation for the determination of organophosphorus pesticides in fruit and vegetable substrates

Dehzoei, Ali Mostafavi January 1991 (has links)
The chromatographic behaviour of four organophosphorus pesticides has been investigated, using capillary gas liquid chromatography-mass spectrometry (GC-MS), and packed and wide bore capillary gas liquid chromatography with electron capture detection (GC-ECD). The first part of this thesis (Chapter 3) embodies the application of high performance capillary gas liquid chromatography-mass spectrometry and the development of the methodology for analysis of pesticides in fruit and vegetable substrates. Manipulation of GC-MS data during the sample analysis is necessary in order to eliminate the problems arising from the complexity of the samples. The application of selected ion monitoring (SIM) in GC-MS is to a large extent limited by selection of the ion for monitoring, selection of internal standard, optimisation of electrometer zero, the electron multiplier voltage, the selected mass interval, column selection for GC-MS analysis and tuning of the quadrupole GC-MS. A major concern was with the determination of the optimum conditions for the analysis of substrates containing organophosphorus pesticides by GC-MS following solvent extraction (without clean up steps). The analysis of organophosphorus samples using GC-MS-SIM provides detection limits lower than Pg pesticide injected and very good recovery data. The second part (Chapter 4) deals with the application of GC-ECD. Here the role of packed column support, packed and wide bore capillary column temperature and detector temperature was investigated. Comparisons of the relative responses of the pesticides analysed (i) on packed columns and (ii) on wide bore capillary column under different column and detector cell temperatures were undertaken and the optimal condition for each of the organophosphorus pesticides was determined, under the optimal conditions the detection limits and recovery for fruit and vegetable samples were examined. The results from this method were correlated with the data obtained by GC-MS and found to be in very good agreement. The data obtained from analysis using GC-ECD was found to have a higher precision than that obtained by GC-MS, however GC-MS exhibited a higher selectivity for the determination of these pesticides.
83

Aluminium-Spezies im Boden und ihre Mobilität /

Schmid, Susanne. January 1989 (has links)
Thesis (doctoral)--Universität-Gesamthochschule-Duisburg, 1989. / Includes bibliographical references (p. 256-272).
84

Analytical solutions for sequentially coupled multi-species reactive transport problems

Srinivasan, Venkatraman. January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. "This thesis has produced the following three journal publications: 1) V. Srinivasan, T.P. Clement, and K.K. Lee. "Domenico solution -- Is it valid?", Ground Water, 25(2): 136-146, May 2007 ; 2) V. Srinivasan and T.P. Clement. "Analytical solutions for sequentially coupled reactive transport problems. Part I: Mathematical derivations", submitted May 2007, Advances in Water Resources ; 3) V. Srinivasan and T.P. Clement. "Analytical solutions for sequentially coupled reactive transport problems. Part II: Special cases, implementation and testing", submitted May 2007, Advances in Water Resources." -- From p. v. Includes bibliographic references (ℓ. 91-98)
85

Attenuation of constituents from paper-pulp mill wastewater ponded on clay soil under natural environmental conditions

Larson, Robert Blake. January 1986 (has links) (PDF)
Thesis (M.S. - Soils, Water and Engineering)--University of Arizona, 1985. / Includes bibliographical references (leaves 63-65).
86

Investigation of radiological contamination of soil samples from Idaho National Laboratory

Payne, Rosara Faith, January 2006 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, August 2006. / Includes bibliographical references (p. 64). Also available online.
87

Soil washing and post-wash biological treatment of petroleum hydrocarbon contaminated soils /

Bhandari, Alok, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 102-106). Also available via the Internet.
88

Optimization of hydrocarbon biodegradation in a sandy soil /

Toccalino, Patricia, January 1992 (has links)
Thesis (Ph. D.), Oregon Graduate Institute of Science & Technology, 1992.
89

Lead isotopic chronologies from inland lakes watershet vs. regional scale sources of lead in the great lakes region /

Benedict, Meredith Lee. January 2006 (has links)
Thesis (M.S.)--Michigan State University. Dept. of Geological Sciences, 2006. / Title from PDF t.p. (viewed on Nov. 20, 2008) Includes bibliographical references (p. 76-80). Also issued in print.
90

The measurement, partitioning and near-field modeling of perfluorooctanoate (PFO) in air

Barton, Catherine Arundel. January 2008 (has links)
Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Steven K. Dentel, Dept. of Civil & Environmental Engineering. Includes bibliographical references.

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