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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.
341

Oxidation of azaphenothiazines

Smith, Robert Evan 01 August 1977 (has links)
A series of mono- and diazaphenothiazines have been synthesized. The oxidation potentials of these compounds have bee[n] determined and discussed. The ESR spectra for the free radical form of these compounds have been recorded and discussed. The relative stabilities of the free radical form of these ring systems in concentrated sulfuric acid have been reported. The synthesis of 2-hydrazino-3,4-diazaphenothiazine and 3,4-diazaphenothiazine have been reported for the first time.
342

Determination of toluene's degradation products under simulated atmospheric conditions

Dumdei, Bruce E. 01 January 1984 (has links)
The reactions of aromatic hydrocarbons represent a major area of uncertainty in urban atmospheric photochemistry. Much effort has been spent studying the simulated atmospheric oxidation chemistry of model aromatics, such as toluene, in order to delineate their reaction mechanisms. These studies are motivated both by interest in fundamental processes and a desire to discover an aromatic's contribution to the formation of ozone in polluted ambient atmospheres. Previous work on toluene includes both product studies and proposed mechanisms. In all previous studies, the combined product yields are half or less of the initially reacted toluene. A major reason for the poor carbon balances found in these studies in the precipitation of intermediate reaction products from the gas phase to the reaction walls. We have studied the oxidation process by blacklight irradiation of 1-10 ppm each of toluene and oxides of nitrogen in 22-liter pyrex flasks, in zero-air at 50% relative humidity. The products were recovered from the walls by exrtraction with methanol or dichloromethane. Some gas-phase products were recovered in the solvent as well. The extracts were analyzed on a Finnigan MAT triple stage quadrupole mass spectrometer/data system by direct probe injection. Once their molecular weights were determined, the products were fragmented by collision-induced-dissociation (CID) in the middle quadrupole to produce characteristic daughter ions. To assist in the spectral interpretation, toluene in three isomeric forms was subjected to simulated atmospheric reaction. In addition to normal (H8) toluene, methyl-deuterated (D3) and per-deuterated (D8) toluene were used. This study confirmed the existence of a number of products identified in past studies, confirmed the formation of some products which have been hypothesized in several proposed mechanisms for toluene oxidation, identified a number of previously unidentified and unproposed products. Detailed mechanistic steps have been outlined for all reaction products' formation and destruction. Other analytical techniques including GC, GC/MS, and HPLC, have supplemented the MS/MS analysis. These results and the further study of the types of compounds identified should make a significant contribution to the understanding of atmospheric aromatic systems.
343

Oxidation of Ferrocene Derivatives with Dibenzoyl Peroxide and meta-Chloroperoxybenzoic Acid

Halstead, Joshua M. 26 November 2018 (has links)
No description available.
344

Catalytic partial oxidation of methyl acetate as a model to investigate the conversion of methyl esters to hydrogen

Nguyen, Betty Ngoc Thy, 1982- January 2007 (has links)
No description available.
345

The oxidation of organic compounds with special reference to hydrogen peroxide.

Hill, Allan C. January 1929 (has links)
No description available.
346

The Oxidation Kinetics of Zirconium at 800°C and 850°C

Kazi, Hamiduzzaman 05 1900 (has links)
N/A / Thesis / Master of Engineering (ME)
347

Kinetics of the laccase-catalyzed oxidation of aqueous phenol

Soegiaman, Selvia Kurniawati. January 2006 (has links)
No description available.
348

Photocatalytic Properties of Zinc Oxide in Oxidation Reactions

Qasim, Mohammad M. January 1964 (has links)
No description available.
349

A study of the oxidation mechanism in columbium-zirconium and columbium-zirconium-titanium alloys at elevated temperatures /

Gordon, Gerald Myron January 1959 (has links)
No description available.
350

The oxidative condensation of ortho-amino-phenols to form aminophenoxazones /

Yembrick, Charles January 1961 (has links)
No description available.

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