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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.
41

Allene cyclization chemistry application to the syntheses of helical polycyclic aromatic hydrocarbons and the ABCD ring core of the camptothecin family of alkaloids /

Dai, Weixiang. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xiii, 287 p. : ill. Includes abstract. Includes bibliographical references (p. 114-123).
42

Synthesis of polycyclic aromatic hydrocarbons via benzannulated enediynyl alcohols

Parbin, Elbin Sehnza. January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 65 p. : ill. Includes abstract. Includes bibliographical references (p. 33-36).
43

The determination of trace organic micro-pollutants by particle beam liquid chromatography mass spectrometry

White, John January 2000 (has links)
Liquid Chromatography/ Mass Spectrometry (LC/MS) is used to interface the separating power of LC with the sensitivity and specificity of MS for the determination of trace levels of organic compounds in a variety of matrices. The technique is finding increasing application in the field of environmental and pharmaceutical analysis. Particle Beam LC/MS (PB/LC/MS) uses a particle beam interface to connect the LC to the MS. This interface design has the advantage of being able to produce "classical" electron impact (El) spectra which can then be searched against commercial MS libraries. The aim of this work was to apply PB/LC/MS to a range of new problems in environmental analysis and evaluate the usefulness of this technique. PB/LC/MS was used to determine compounds that cannot easily be analysed by more conventional techniques such as gas chromatography with mass spectrometry (GC/MS) or liquid chromatography with UV/vis detection (LC/UV). For example, some polycyclic aromatic hydrocarbons (PAH) are too involatile to analyse by GC/MS, some commonly prepared isocyanate derivatives cannot be accurately identified by LC/UV and some classes of pesticides are thermally labile and so cannot be determined by GC/MS.The work presented in this thesis examines the factors affecting the sensitivity and performance of PB/LC/MS and comparisons are made with other analytical methods. Compound classes examined are polycyclic aromatic hydrocarbons (PAH), pesticides and isocyanate derivatives in a variety of environmental matrices. Methods for improving the sensitivity of PB/LC/MS are investigated and the results of these experiments used to compare the different models are used to explain PB/MS behaviour. Conclusions regarding the accuracy of these models are then made. The ability of PB/MS to provide useful El MS for identification purposes in complex environmental matrices is also investigated.
44

Analysis of nitrated polynuclear aromatic hydrocarbons in urban air

Xu, Jinhui 01 January 1999 (has links)
No description available.
45

Identification and toxicological evaluation of polycyclic aromatic hydrocarbons in used crankcase oil. / CUHK electronic theses & dissertations collection

January 1996 (has links)
by Jian Wang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (p. 154-171). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
46

Degradation and detoxification of polycyclic aromatic hydrocarbons (PAHs) by photocatalytic oxidation.

January 2002 (has links)
Yip, Ho-yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 181-201). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Contents --- p.vi / List of Figures --- p.x / List of Tables --- p.xvii / Abbreviations --- p.xix / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Polycyclic aromatic hydrocarbons (PAHs) --- p.1 / Chapter 1.1.1 --- Characteristics of PAHs --- p.1 / Chapter 1.1.2 --- Sources of PAHs --- p.2 / Chapter 1.1.3 --- Environmental fates of PAHs --- p.3 / Chapter 1.1.4 --- Effects of PAHs on living organisms --- p.5 / Chapter 1.1.4.1 --- General effects --- p.5 / Chapter 1.1.4.2 --- Effects on plants --- p.6 / Chapter 1.1.4.3 --- Effects on invertebrates --- p.7 / Chapter 1.1.4.4 --- Effects on fishes --- p.7 / Chapter 1.1.4.5 --- Effects on reptiles and amphibians --- p.8 / Chapter 1.1.4.6 --- Effects on birds --- p.9 / Chapter 1.1.4.7 --- Effects on mammals --- p.9 / Chapter 1.2 --- PAH contamination in Hong Kong --- p.10 / Chapter 1.3 --- Treatments of PAH contamination --- p.12 / Chapter 1.3.1 --- Physical treatments --- p.12 / Chapter 1.3.2 --- Chemical treatments --- p.13 / Chapter 1.3.3 --- Biological treatments --- p.14 / Chapter 1.4 --- Advanced oxidation processes (AOPs) --- p.16 / Chapter 1.5 --- Summary --- p.24 / Chapter 2. --- Objectives --- p.27 / Chapter 3. --- Materials and Methods --- p.28 / Chapter 3.1 --- Chemicals --- p.28 / Chapter 3.2 --- Photocatalytic reactor --- p.30 / Chapter 3.3 --- Determination of PAHs concentrations --- p.30 / Chapter 3.3.1 --- Extraction of PAHs --- p.30 / Chapter 3.3.2 --- Quantification of PAHs --- p.32 / Chapter 3.4 --- Optimization of physico-chemical conditions for PCO --- p.37 / Chapter 3.4.1 --- Determination of the reaction time for optimization of PCO --- p.37 / Chapter 3.4.2 --- Effect of titanium dioxide (Ti02) concentration and light intensity --- p.38 / Chapter 3.4.3 --- Effect of initial pH and hydrogen peroxide (H2O2) concentration --- p.38 / Chapter 3.4.4 --- Effect of initial PAHs concentration --- p.39 / Chapter 3.5 --- Toxicity analysis --- p.39 / Chapter 3.5.1 --- Microtox® test for acute toxicity --- p.39 / Chapter 3.5.2 --- Mutatox® test for genotoxicity --- p.42 / Chapter 3.6 --- Determination of total organic carbon (TOC) removal in optimized PCO --- p.43 / Chapter 3.7 --- Determination of degradation pathways --- p.43 / Chapter 3.7.1 --- Extraction of intermediates and/or degradation products --- p.45 / Chapter 3.7.2 --- Identification of intermediates and/or degradation products --- p.45 / Chapter 4. --- Results --- p.49 / Chapter 4.1 --- Determination of PAHs concentrations --- p.49 / Chapter 4.2 --- Optimization of extraction method --- p.49 / Chapter 4.3 --- Optimization of physico-chemical conditions for PCO --- p.49 / Chapter 4.3.1 --- Determination of the reaction time for optimization of PCO --- p.49 / Chapter 4.3.2 --- Effect of Ti02 concentration and light intensity --- p.60 / Chapter 4.3.3 --- Effect of initial pH --- p.88 / Chapter 4.3.4 --- Effect of initial H2O2 concentration --- p.99 / Chapter 4.3.5 --- Effect of initial PAHs concentration --- p.104 / Chapter 4.3.6 --- Improvements on removal efficiency (RE) after optimization --- p.113 / Chapter 4.4 --- Toxicity analysis --- p.122 / Chapter 4.4.1 --- Microtox® test for acute toxicity --- p.122 / Chapter 4.4.2 --- Mutatox® test for genotoxicity --- p.122 / Chapter 4.5 --- Determination of TOC removal in optimized PCO --- p.129 / Chapter 4.6 --- Determination of degradation pathways --- p.129 / Chapter 5. --- Discussion --- p.150 / Chapter 5.1 --- Determination of PAHs concentrations --- p.150 / Chapter 5.2 --- Optimization of extraction method --- p.150 / Chapter 5.3 --- Optimization of physico-chemical conditions for PCO --- p.151 / Chapter 5.3.1 --- Determination of the reaction time for optimization of PCO --- p.151 / Chapter 5.3.2 --- Effects of Ti02 concentration and light intensity --- p.152 / Chapter 5.3.3 --- Effects of initial pH --- p.160 / Chapter 5.3.4 --- Effects of initial H202 concentration --- p.163 / Chapter 5.3.5 --- Effects of initial PAHs concentration --- p.165 / Chapter 5.3.6 --- Improvements on RE after optimization --- p.167 / Chapter 5.4 --- Toxicity analysis --- p.169 / Chapter 5.4.1 --- Microtox® test for acute toxicity --- p.169 / Chapter 5.4.2 --- Mutatox® test for genotoxicity --- p.170 / Chapter 5.5 --- Determination of TOC removal in optimized PCO --- p.171 / Chapter 5.6 --- Determination of detoxification pathways --- p.172 / Chapter 6. --- Conclusion --- p.177 / Chapter 7. --- References --- p.181 / Chapter 8. --- Appendix I --- p.202
47

Factors that influence atmospheric concentration of semi-volatile organic compounds

Lee, Robert George Marlor January 1999 (has links)
No description available.
48

Polycationic arene chromium tricarbonyl complexes

Christofi, Anna Maria January 1999 (has links)
No description available.
49

Fish bile metabolites : the assessment of PAH contamination in aquatic ecosystems

Ruddock, Peter John January 2001 (has links)
No description available.
50

Percutaneous absorption and metabolism of naphthalene and phenanthrene

Supanpaiboon, Wisa January 2001 (has links)
No description available.

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