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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.
61

Appraisal and validation of rapid, integrated chemical and biological assays of environmental quality

Fillmann, Gilberto January 2001 (has links)
To assess the significance of pollutants released into the environment it is necessary to determine both the extent of contamination and the biological effects they give rise to. This research is based on a tiered system, which commences with conventional analytical chemistry (gas chromatography), followed by the development, evaluation and application of rapid and simple immunochemical techniques and, finally, the integration of chemical and biological markers to assess pollution. GC-ECD/FID/MS have been used to investigate the status of chemical contamination of the Black Sea by organochlorine residues, hydrocarbons and faecal sterols. Useful information is provided and problems with e.g. HCHs and sewage contamination are highlighted. Contamination by DDTs, PCBs, "total" hydrocarbons and PAHs is also reported. Next, these techniques are used to develop rapid screening methods. Four distinct applications of immunochemical techniques are presented. Initially, the BTEX RaPDD Assay® ELISA is evaluated to detect semi-volatile hydrocarbons in contaminated groundwater. Although overestimating concentrations when compared to GC-FID/PID, results are well correlated. Secondly, the effectiveness o f the BTEX and c-PAH RaPID Assay® to detect hydrocarbons in sediments is tested. Once again, good agreement with GC-FID/MS confirms the ELISA to be a useful screening protocol to focus more expensive high-resolution analytical techniques. The adaptability and applicability of an ELISA (PCB RaPID Assay®) method in measuring "total" PCB levels in mussel tissue is demonstrated. An underestimation of concentrations, despite of covariability between ELISA and cGC-ECD, is discussed. Next, ELISA (RaPID Assay®) and fluorometry were successfully applied to quantify PAH metabolites in crab urine as a measure of exposure. HPLC analyses indicated that conjugate PAH metabolites were dominant in urine of crabs exposed to pyrene. Differences could also be identified between crabs taken from clean and contaminated sites. Finally, an integration of chemical and biological techniques is used to investigate contamination and effects in mussels within a pollution gradient. Results indicate a correlation between micronucleus formation, heart rate and PCB and PAH level.
62

The gas-chromatographic determination of trace organic pollutants in aqueous samples.

January 1986 (has links)
by Wu Siu Yu Portia. / Bibliography: leaves 105-107 / Thesis (M.Ph.)--Chinese University of Hong Kong
63

Design of solid state composites for enantiomeric separations /

Alcala Saavedra, Monica, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 140-153). Available also in a digital version from Dissertation Abstracts.
64

The determination of the activity coefficient of a volatile component in a binary system by gas-liquid chromatography

Chueh, Chun Fei 08 1900 (has links)
No description available.
65

Polymer solution thermodynamics and gas-liquid chromatography

Su, Chung-Sin January 1976 (has links)
No description available.
66

Identification of flavor components of loganberry essence

Miller, Phillip Harry 14 May 1962 (has links)
Graduation date: 1962
67

Motion sensitivity of flame ionization detectors /

Gularte, Ronald Carl. January 1972 (has links)
Thesis (Ocean Engineer)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution. / Includes bibliographical references.
68

Relationship between chromatographic retention and donor and acceptor numbers /

Michelsen, Peter J. January 1990 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1990. / Spine title: Chromatographic retention and donor and acceptor numbers. Typescript. Includes bibliographical references.
69

Studies in protein chemistry I. Acetylated chain termini : II. Anti-dinitrophenyl gamma-globulin.

Omilianowski, Daniel Roman, January 1966 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 34-36).
70

Superheated water as a mobile phase

Burgess, Robert John January 1999 (has links)
This project has focused on the applicability of using superheated water as an alternative eluent for use in reversed phase high performance liquid chromatography (RP-HPLC). A system based on instrumentation from gas chromatography (GC), HPLC, and supercritical fluid chromatography (SFC) was utilised with some success. Of particular importance was the stability of the column stationary phases commonly employed in RP-HPLC. The most popular phases based on alkyl bonded silica proved unsuitable due to excessive dissolution of the base silica at high temperatures. Nevertheless, two other phases—one a poly(styrene-divinylbenzene) material and the other a porous graphitic carbon—proved stable to temperatures as high as 240°C. At such temperatures compound stability was good, except for a notable case with nitrobenzene. The mechanism of elution remained reversed phase mode throughout, with polar solutes being eluted before non-polar ones.

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