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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

Cascade radical cyclizations of benzannulated enyne-allenes and development of new synthetic strategies for novel polycyclic aromatic compounds

Yang, Yonghong, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xii, 201 p. : ill. Includes abstract. Includes bibliographical references (p. 109-123).
42

Cyclizations of enyne-allenes to form persistent biradicals and polycyclic aromatic hydrocarbons with carbon frameworks represented on the surface of C₆₀

Zhang, Hai-Ren. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains viii, 116 p. : ill. Includes abstract. Includes bibliographical references (p. 105-116).
43

Effects of plant flavonoids on the fate of polynuclear aromatic hydrocarbons in rhizosphere soil

Qiu, Xiujin. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains xv, 405 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 199-208).
44

Polycyclic compounds of manganese /

Reginato, Nada. McGlinchey, Michael J. January 2003 (has links)
Thesis (Ph. D.)--McMaster University, 2003. / Advisor: M. McGlinchey. Includes bibliographical references (leaves 182-195). Also available via World Wide Web.
45

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).
46

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).
47

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.
48

Analysis of nitrated polynuclear aromatic hydrocarbons in urban air

Xu, Jinhui 01 January 1999 (has links)
No description available.
49

The preparation of polycyclic aromatic compounds

Shuttleworth, A. J. January 1965 (has links)
No description available.
50

Analytical Evaluation Of The Fluorescence Characteristics Of Metabolites Of Polycyclic Aromatic Hydrocarbons At Room, Liquid Nitrogen And Liquid Helium Temperatures

Vatsavai, Keerthika 01 January 2007 (has links)
Although environmental monitoring of polycyclic aromatic hydrocarbons (PAH) is an essential step to prevent human exposure to contaminated sites, it provides little information on the actual human uptake and subsequent risks. To this end, urine analysis of short-term biomarkers such as PAH metabolites fill an important niche. The general approach follows the sequence of urine hydrolysis, sample clean-up and pre-concentration, chromatographic separation and determination. Whereas chromatographic methods are based on well established laboratory techniques, the development of easy-to-use, cost-effective and large sample throughput techniques is becoming increasingly relevant to investigate adverse PAH effects on large human populations. This thesis compares the room-temperature, 77K and 4.2K fluorescence properties of 1-naphthol, 2-naphthol, 1-hydroxypyrene, 2-hydroxyfluorene, 3-hydroxybenzopyrene and 9-hydroxyphenanthrene. These metabolites are used as model biomarkers to investigate the analytical potential of a simple method of analysis based on Solid-Phase Extraction and Room-Temperature Fluorimetry. Metabolites are directly determined in the eluting solvent (methanol) without the need of previous separation via multidimensional formats. Metabolite recoveries varied between 87 ± 1.51% (9-hydroxyphenanthrene) and 99 ± 1.05% (3-hydroxybenzopyrene). For 10mL of urine samples, limits of detection varied between 0.01ng.mL-1 (3-hydroxybenzopyrene) and 0.6ng.mL-1 (2-hydroxynaphthalene). These figures of merit demonstrate the potential of this approach for screening purposes

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