No description available.

Thesis (Ph. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 220-229).

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 226-231). Also available in electronic version. Access restricted to campus users.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 126-129).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 161-167).

Thesis (M.Sc.)--Memorial University of Newfoundland, 1994. / Typescript. Bibliography: leaves [116]-122. Also available online.

No description available.

The ease of electron loss of fifty alipathic thioethers was studied by electrochemistry, charge transfer and photoelectron spectroscopy. These compounds consisted of mesocyclic thioethers and S-methyl norbornane derivatives. Comparison of charge transfer and photoelectron ionization potential showed a good correlation. Correlation of ionization potential with anodic peak potentials showed the existence of two groups of compounds. Those compounds having an electron rich neighboring group capable of an intramolecular interaction were found to have a good correlation of ionization potential with electrochemical peak potential. For those compounds without this capability, no observable correlation was seen. Photoelectron ionization potentials of thioethers are a function of the alkyl groups attached to the sulfur atom. With substituent constants assigned to alkyl groups from measurements on simple thioethers, the ionization potential of more complicated thioethers can be calculated. Compounds whose experimental value was found to be less than the calculated value were found to fall in the group where an intramolecular neighboring group could facilitate the ease of electron loss by stabilization of the cation radical. Electrochemical peak potentials were seen to be dramatically affected by intramolecular stabilization of the cation radical. Shifts of 600-800 mV were seen for structurally similar compounds whose only difference was the availability of an electron rich neighboring group. Since the electrochemistry of these compounds exhibits irreversible behavior, the shift in peak potential could be due to a change in the formal potential, the heterogeneous rate constant, the rate of a following chemical reaction or a combination of these. Changes in the heterogeneous rate constant or chemical step rate constant alone cannot account for the magnitude of the shift seen. Thus the differences observed must be due to two different processes. In the noninteracting case, E⁰' is a measure of the formation of the cation radical, whereas, in the case of interacting compounds E⁰') is a measure of the formation of an intramolecularly stabilized cation radical where bond formation has occurred. Evidence for the structure of some intramolecular stabilized intermediates is presented. An electron deficient thioether which is a model for biological systems was shown to be capable of phosphorylating adenine nucleotides.

The toxic effects of degrading the chlorinated hydrocarbons trichloroethylene (TCE), chloroform (CF) and cis-1,2-dichloroethylene (cis-1,2-DCE) were studied in the bacterium Nitrosomonas europaea. N europaea is an ammonia-oxidizing bacterium that obtains all of its energy from the oxidation of ammonia to nitrite. This metabolic process involves two enzymes, ammonia monooxygenase (AMO) and hydroxylamine oxidoreductase (HAO). AMO has a broad substrate range and is also capable of oxidizing TCE, CF, and cis-1,2-DCE. Effects of degrading these chlorinated compounds on both AMO and HAO were studied. Cells were inactivated with known inhibitors of both AMO (light) and HAO (hydrogen peroxide) to provide comparison studies. Oxidation of the three chlorinated hydrocarbons did not always result in similar toxic effects to the cells. Whole cell studies indicated that oxidation of TCE and CF resulted in a loss of both NH������- and N���H���- dependent 0��� uptake rates, while in vitro studies indicated that at lower concentrations of both TCE (���0.05 mM) and CF (���0.10 mM) neither AMO or HAO appear to be the primary sites of inactivation. The oxidation of cis-1,2-DCE appeared to specifically inactivate AMO both in in vivo and in vitro assays. N europaea cells were also pretreated with the AMO inhibitor acetylene and incubated with the chlorinated hydrocarbons. Results of both whole cell 0��� uptake rates and the in vitro HAO assay confirms the hypothesis that the chlorinated hydrocarbons must be turned over in order to produce a toxic effect in N. europaea cells. / Graduation date: 1999

Graduation date: 1997