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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.
111

Über Expansion und Kontraktion von Goldlegierungen und Ihren Ausgleich beim Guss durch entsprechende Massnahmen Inaugural-Dissertation /

Appel, Erwin, January 1938 (has links)
Thesis (doctoral)--Ludwig-Maximilians-Universität München, 1938.
112

Investigation of a dental gold alloy and its ceramic bonding

Yli-Urpo, Antti. January 1975 (has links)
Thesis--University of Turku. / At head of title: From the Department of Prosthetics, Institute of Dentistry, University of Turku, Finland. Translated by Mr. and Mrs. Antony Landon. Bibliography: p. 91-96.
113

Secondary defects in quenched gold and gold-zinc

Hussein, Abdel-Hamid Ahmed, January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
114

Über Expansion und Kontraktion von Goldlegierungen und Ihren Ausgleich beim Guss durch entsprechende Massnahmen Inaugural-Dissertation /

Appel, Erwin, January 1938 (has links)
Thesis (doctoral)--Ludwig-Maximilians-Universität München, 1938.
115

Electrochemical studies of gold bioaccumulation by yeast cell wall components

Lack, Barbara Anne January 1999 (has links)
Gold, amongst other group 11 metals, was almost certainly one of the first three metals known to man. In addition to the economic importance of the metal, gold has a wide variety of applications in the medical, electrocatalytical and micro-electronics fields. However, the determination of gold ions in solution, with accuracy, precision, sensitivity and selectivity is still an interesting and much debated topic in analytical chemistry. A system whereby gold ions have been successfully detected employing an electrochemical technique, known as stripping voltammetry, has been developed. The electrochemical method was chosen over other available techniques for the sensitivity, particularly at low concentrations, and selectivity properties; notably in the presence of other metal ions. Under acidic conditions, the electrochemical technique was applied and the presence of gold(III), at a concentration of 2.53 x 10⁻⁵ mol dm⁻³ in a mine waste water sample, was detected. Biomass, in particular yeast and algal types, have been successfully employed in extracting low concentrations of gold ions from industrial effluents. The manipulation of the biological facility for mineral interaction, biohydrometallurgy, may yield numerous potential new technologies. South Africa in particular would benefit from this area of research, since the country is a major ore and metal refining country and if the output and the efficiency of the mines could be improved, even by a small percentage, the financial rewards would be vast. In this study, the application of adsorptive cathodic stripping voltammetry (AdCSV) of gold(III) in the presence of various Saccharomyces cerevisiae cell wall components, was investigated to determine which, if any, were involved specifically in the chemical binding of the gold ions. The chitin and mannan extracts showed the most promise with detection limits of 1.10 x 10⁻⁶ mol dm⁻³ and 9 x 10⁻⁹ mol dm⁻³, respectively; employing the AdCSV technique. A modification of the stripping voltammetry technique, Osteryoung square wave stripping voltammetry (OSWSV), provided the lowest detection limit, for gold(IIl) in the presence of mannan, of 1.70 x 10⁻¹¹ mol dm⁻³ ; utilising a modified carbon paste electrode. The detection of gold(III) has been shown to be dependent on the type of electrode employed, the electrolyte solution and the presence of interfering agents. The effect of copper(II) and silver(I) on the detection of the gold(III) in solution was investigated; whilst the silver(I) has shown no detrimental effects on gold (III) detection systems, copper(II) has indicated the possibility of forming an inter-metallic compound with the gold(III). However, mannan has shown to selectively and preferentially bind the gold(III) in the presence of a ten-fold excess of copper(II). Nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy, as well as computer modelling techniques were employed to further investIgate the mannan-gold(III) interaction and proposed complex formed. The NMR, IR and computer modelling data are in agreement with the electrochemical data on proposing a mannan-gold(III) complex. The co-ordination site was established to be in the vicinity of the H-I and H-2 protons and the gold(III) adopts a square-planar geometry upon co-ordination. The benefits of the research are useful from a biological perspective (i. e. as more is known about the binding sites, microbiologists/biochemists may work on the optimisation of parameters for these sites or work could be furthered into the enhanced expression of the sites) and an industrial one. In addition to the' two major benefits, an improved understanding of gold and its chemistry would be achieved, which is advantageous for other fields of research as well.
116

Minimising uncertainty in measurement and improving limit of detection in gold bearing materials from concentrations predicted by linear regression in atomic absorption spectrometry

Fraser, Allan William 09 November 2015 (has links)
M.Sc. (Geology) / Refer to full text for abstract
117

Characterisation of activated carbon used for gold adsorption

Seke, Makunga Daudet 21 December 2006 (has links)
The full text of this thesis/dissertation is not available online. Pending permission from the author/supervisor access may be provided on <a href="mailto:upetd@up.ac.za">request.</a> Read the abstract in the section 00front of this document. / Dissertation (M Eng (Metallurgical Engineering))--University of Pretoria, 2006. / Materials Science and Metallurgical Engineering / unrestricted
118

The modelling of the binary adsorption of gold and zinc cyanides onto a strong base anion exchange resin

Glover, Michael Richard Lister 05 February 2015 (has links)
No description available.
119

Gold sodium thiomalate : selected aspects of metabolism and distribution /

Turkall, Rita January 1979 (has links)
No description available.
120

A wet method for analyzing gold-silver alloys of high gold content /

Shank, Lowell William January 1966 (has links)
No description available.

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