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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

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.
62

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).
63

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).
64

Intramolecular radical additions to aromatic compounds

Blumire, Nigel James January 2003 (has links)
This thesis is concerned with the development of cyclisation strategies that allow entry to polycyclic heterocycles and medium sized ring systems. Radical additions to pyridines are developed and methodologies explore the differences between the homolysis of C-Br and C-I bonds. Mechanisms are described for the unexpected ipso additions to the pyridines. Work towards the synthesis of the stegnans and dimethylgomisin illustrates the attempts to utilise the ipso addition to form medium sized ring systems. A new method of synthesising these medium sized ring systems is discussed. Progress towards a general methodology is described and shows the opportunities for which it could be utilised. A literature review of the synthesis of heterocycles via radical cyclisations is presented.
65

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.
66

Analysis of nitrated polynuclear aromatic hydrocarbons in urban air

Xu, Jinhui 01 January 1999 (has links)
No description available.
67

The preparation of polycyclic aromatic compounds

Shuttleworth, A. J. January 1965 (has links)
No description available.
68

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
69

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.
70

N-(2'-deoxyguanosine-8-YL)-N-acetyl-2-aminofluorene induced translesion synthesis events in E. Coli: role of Y-family error-prone polymerases and the DNA sequence context /

Nokhbeh, M. Reza January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2004. / Includes bibliographical references (p. 193-221). Also available in electronic format on the Internet.

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