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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.
101

A lithogeochemical study of the host rocks of the Strickland showing /

Wynne, Paula Jane, January 1983 (has links)
Thesis (M.Sc.) -- Memorial University of Newfoundland. / Bibliography : leaves 266-277. Also available online.
102

Application of electrical prospecting methods to two types of sulphide ore deposits

Van Nostrand, Robert, January 1949 (has links) (PDF)
Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1949. / Vita. The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed July 12, 2010) Includes bibliographical references (p. 50-51).
103

Environmental applications of ESI FT-ICR mass spectrometry oxidized peptides and metal sulfide clusters /

Spraggins, Jeffrey M. January 2010 (has links)
Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisor: Douglas Ridge, Dept. of Chemistry & Biochemistry. Includes bibliographical references.
104

The behavior of iron and manganese sulfides during the solidification and processing of steels containing vanadium, titanium, and zirconium

Harris, Kenneth Wesley, January 1969 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
105

The hydrogen reduction of silver, copper, nickel, cobolt and iron sulfides and the formation of filamentary metal

Cech, Robert Edward, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
106

Metal sulfides in oxidizing freshwater systems /

Manolopoulos, Helen. January 2001 (has links)
Thesis (Ph.D.) -- McMaster University, 2000 / Includes bibliographical references (leaves 139-150). Also available via World Wide Web.
107

The design and building of an alternating current scanning tunneling microscope for nanometer scale imaging of insulating surfaces /

Schafer, Adam Jay David. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 183-190).
108

Removal and recovery of aluminium and sulphate ions from an alkaline medium using solvent extraction

Mpinga, Cleophace Ngoie January 2009 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Chemical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology / Throughout the world, many water resources are polluted by industrial and domestic effluents, acid mine drainage, etc. The increasing awareness and concern about the environment has motivated in the recent years extensive research into developing new efficient, cost effective and environmentally sound technologies to treat industrial solutions bearing metals and sludges. From the literature review, much research has been, and is still being devoted to the performance of solvent extraction (SX) of aluminium or sulphate in acidic solutions and how to improve such performance. There is a general lack of information on liquid-liquid extraction of aluminium or sulphate in an alkaline solution. Thus, the need for a systematic investigation into the solvent extraction of aluminium and sulphate in an alkaline medium was important. This thesis focuses on the study of solvent extraction of aluminium and sulphate from alkaline solutions using Trioctylmethylammonium chloride, (Aliquat 336), in Kerosene as diluent.
109

Biological sulphide oxidation in heterotrophic environments

Rein, Neil Berthold January 2002 (has links)
Acid mine drainage is a major environmental pollution concern associated with the mining of sulphide-containing ore bodies. Both physicochemical and biological options have been investigated for the treatment of acid mine drainage with recent interest in biological processes targeting low-cost and passive treatment applications. All acid mine drainage biological treatment processes are based to some extent on the activity of sulphate reducing bacteria, and their ability to reduce sulphate to sulphide in the presence of a range of carbon and electron donor sources. A portion of the sulphide produced may be consumed in the precipitation of heavy metals present in the mine drainage. Residual sulphide must be removed, not only due to its toxicity, but especially to prevent its reoxidation to sulphate where salinity reduction is a target of the treatment process. The partial oxidation of sulphide to elemental sulphur is an option that has received considerable attention and both physicochemical and biological options have been investigated. Biological processes have substantial potential cost advantages and run at ambient temperatures and pressures. However, the oxidation of sulphide to elemental sulphur is poised over a narrow redox range and process control to maintain optimum conditions remains a serious problem. In addition little has been reported in the literature on process control of sulphide oxidation to elemental sulphur, in the heterotrophic conditions prevailing in the reaction environment following sulphate reduction. This study undertook an investigation of biological sulphide oxidation under heterotrophic conditions in order to establish the effect of organic compounds on biological sulphide oxidation, and to determine whether the presence of organics, and associated heterotrophic oxygen consumption, may be manipulated to maintain the defined redox conditions required for the production of elemental sulphur. Biological sulphide oxidation under heterotrophic conditions was investigated in a series of flask experiments. Based on these results three different reactor configurations, a Fixed-Film Trickle Filter Reactor, Submerged Fixed-Film Reactor and a Silicone Tubular Reactor were used to investigate sulphur production. The flask studies indicated that organics, and associated heterotrophic metabolism in the presence of excess oxygen in the sulphide oxidation reaction environment, did contribute to the poising of redox conditions and thereby enabling the production of elemental sulphur. While the Fixed-Film Trickle Filter Reactor was found to be redox unstable, probably due to excess oxygen ingress to the system, a reduced oxygen challenge in the Submerged Fixed-Film Reactor configuration was found to be more successful for production of elemental sulphur. However, due to the production of a predominantly filamentous sulphur producing microbial population, recovery of sulphur from the column was intermittent and unpredictable. Extended residence times for produced sulphur on the column increased the likelihood for its eventual oxidation to sulphate. The Silicone Tubular Reactor was found to support a vigorous sulphide oxidising biofilm and produced elemental sulphur effectively. Electron microscopic studies showed that this occurred as both biologically produced sulphur and, probably mainly, as crystalline sulphur in the ortho-rhomic form. Given the linear extension of the sulphur production reaction environment it is was possible to investigate the sequence of the reaction mechanism in grater detail than is possible in mixed systems. Based on these findings a model explaining sulphur production under heterotrophic conditions has been proposed and is presented. The commercial implications of the development have also been noted.
110

Dynamic combinatorial chemistry of hydrazone and disulfide macrocycles

Klein, Jörg Martin January 2011 (has links)
No description available.

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