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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.
1

Optimization of an automated DNPH cartridge system for continous measurement of ambient gaseous carbonyls /

Wang, Pei. January 2007 (has links)
Thesis (M.Sc.)--York University, 2007. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 122-134). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR29309
2

Synthesis of alpha, beta-unsaturated carbonyl compounds using organoselenium reagents

Renga, James Michael, January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 167-179).
3

The decarbonylation of aldehydes using ruthenium porphyrins

Tarpey, Bláithín January 1982 (has links)
The topic of this thesis is the catalytic and stoichiometric decarbonylation of aldehydes. A carbonylation reaction, the reaction of RuTPP(n-Bu₃P)₂ with CO gas was also studied. A catalytic decarbonylation system, using RuTPP(PPh₃)₂ as catalyst plus added excess tri-n-butylphosphine in acetonitrile-dichloromethane, was employed to decarbonylate several organic aldehydes. This system proved to be an effective decarbonylation agent, which also exhibited some selectivity. Some mechanistic studies were carried out in an attempt to elucidate the details of the reaction mechanism. From these and other findings in this laboratory, a tentative mechanism was proposed for the decarbonylation reaction. A radical mechanism, involving Ru(III) intermediates was favoured on the basis of e.s.r. data, spectral evidence and cyclic voltammetry studies. However, no intermediates were isolated. The full details of the mechanism, such as the precise nature of the postulated intermediates, have not been fully determined, although there are indications that solvated species, like RuTPP(CO)(CH₃CN), may be important. The stoichiometric reaction between RuTPP(n-Bu₃P)₂ and phenylacetaldehyde was also studied. The kinetic analysis indicated that the reaction, equation i, RuTPP(n-Bu₃P)₂ + C₆H₅CH₂CH0 --> RuTPP(CO)(n-Bu₃P) + n-Bu₃P + C₆H₅CH₃ equation i followed a pseudo-first-order rate law in the absence of excess phosphine, however, the actual k obsd values were found to be irreproducible. Some features of this reaction, such as the failure of the reaction to go to completion, and also the effect of trace oxygen on the reaction were investigated. The carbonylation of RuTPP(n-Bu₃P)₂ by CO gas was of interest, with respect to the catalytic reaction, which seems to involve pretreatment with CO (or aldehyde) to form a phosphine monocarbonyl. The reaction was found to follow a simple dissociative mechanism, which is similar to that observed for analogous M(porp)L₂, where M = Ru or Fe. A K value of 0.054 at 26°C was obtained and individual rate constants were calculated also. The temperature dependence of K was used to find the thermodynamic parameters ΔS° and ΔH° for the reaction. Some electrochemical studies were performed on RuTPP(n-Bu₃P)₂ and the corresponding monocarbonyl, RuTPP(CO)(n-Bu₃P). Electrochemical oxidation of RuTPP(CO)(n-Bu₃P) yielded a ir-cation radical, whereas bromine oxidation appeared to effect oxidation of the metal. / Science, Faculty of / Chemistry, Department of / Graduate
4

Determination of airborne carbonyl compounds by a thermal desorption GC/MS method : development and application of a vapour coating technique /

Lam, Ka Man. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 118-133). Also available in electronic version.
5

The chemistry of osmium-palladium carbonyl clusters

陳雁菁, Chan, Suzanna. January 1995 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
6

The chemistry of tetraosmium carbonyl clusters

蔡雅然, Choi, Ya-yin. January 1998 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
7

The chemistry of hexa- and hepta- osmium carbonyl clusters

梁士賢, Leung, Sze-yin. January 1999 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
8

The chemistry of triosmium carbonyl clusters containing oxygen and sulphur donor ligands

李兆銘, Lee, Siu-ming. January 1996 (has links)
published_or_final_version / Education / Doctoral / Doctor of Philosophy
9

Synthesis of novel amino acids and peptides by rearrangement of ammonium ylides generated from metal carbenoids

Middleton, Mark D. January 2003 (has links)
No description available.
10

The chemistry of vicinal tricarbonyl compounds: condensation reactions of ethyl 3-phenyl-2, 3-dioxopropanoate

Hudson, Glenn Vincent. January 1950 (has links)
Call number: LD2668 .T4 1950 H84 / Master of Science

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