Thesis (Ph. D.)--University of Sydney, 1977. / Also available in print form.

Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1946. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed June 14, 2010) Includes bibliographical references (p. 40) and index (p. 41).

Thesis (Ph. D.)--University of Michigan, 1986. / Includes bibliographical references (leaves 274-287).

Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (November 8, 2006) Vita. Includes bibliographical references.

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Adherent Cu films were electrodeposited onto polycrystalline W foils from purged solutions of 0.05 M CuSO4 in H2SO4 supporting electrolyte and 0.025 M CuCO3∙Cu(OH)2 in 0.32 M H3BO3 and corresponding HBF4 supporting electrolyte, both at pH = 1. Films were deposited under constant potential conditions at voltages between -0.6 V and -0.2 V versus Ag/AgCl. All films produced by pulses of 10 s duration were visible to the eye, copper colored, and survived a crude test called "the Scotch tape test", which involves sticking the scotch tape on the sample, then peeling off the tape and observing if the copper film peels off or not. Characterization by scanning electron microscopy (SEM)/energy dispersive X-ray (EDX) and X-ray photon spectroscopy (XPS) confirmed the presence of metallic Cu, with apparent dendritic growth. No sulfur impurity was observable by XPS or EDX. Kinetics measurements indicated that the Cu nucleation process in the sulfuric bath is slower than in the borate bath. In both baths, nucleation kinetics does not correspond to either instantaneous or progressive nucleation. Films deposited from 0.05 M CuSO4/H2SO4 solution at pH > 1 at -0.2 V exhibited poor adhesion and decreased Cu reduction current. In both borate and sulfate baths, small Cu nuclei are observable by SEM upon deposition at higher negative overpotentials, while only large nuclei (~ 1 micron or larger) are observed upon deposition at less negative potentials. Osmium metal has been successfully electrodeposited directly onto p-Si (100) from both Os3+ and Os4+ in both sulfuric and perchloric baths. This electrochemical deposition of osmium metal can provide sufficient amount of osmium which overcome ion beam implantation limitations. The deposited metal can undergo further processing to form osmium silicides, such as Os2Si3, which can be used as optical active materials. The higher osmium concentration results in large deposition currents and more negative peak potential due to larger transfer coefficient. No matter which supporting electrolyte is used, no stripping peak exists in this study. The oxidation ability of anion plays an important role in osmium electrodeposition because it will change the silicon substrate conductivity. In our case, perchloric acid oxidized silicon surface severely. Os4+ seems more favorable for reduction but has a stronger oxidization ability to lower the conductivity. The microscopic images verified osmium is deposited on silicon and forms cluster sizes of < 1 µm to > 10 µm. The Rutherford backscattering spectroscopy (RBS) data indicate osmium can diffuse into the silicon as far as 500 nm and the Si crystal structure is unchanged by the process. This means that the Si does not disassociate and migrate into deposited Os. Osmium is distributed randomly throughout the lattice interstitially. It appears field assisted diffusion can significantly drive the Os into Si (100). This finding is very valuable but needs further study.

No description available.

Many divergent opinions have been expressed concerning the possible priority of the use of copper or iron in the early history of mankind. Too often have archaeologists based their. conclusion solely upon the relative abundance of these meta;ts, which have since been found in ancient ruins, especially in graves and tombs. It is true that among such remains copper has usually proven to be the more predominant metal. This need not, however, be too readily regarded as an indication of its earlier use by mankind, as some writers have been prone to conclude. The higher corrodibility of iron as compared with copper, and particularly with its alloys, would tend to destroy evidences of that metal within a relatively short time. Furthermore, it must be remembered that it was the custom of early peoples to place in the graves of their kindred, articles of intrinsic value, and this practice could tend to account for the absence of iron in such ruins. Excavations of the Lake Dwellings of Switzerland have revealed intermingled remnants of both stone and bronze implements. It has been found however, that the latter are of such perfection as to be attributable only to a later civilization, and thus they were probably introduced at a subsequent date. Moreover, from the standpoint of economic geology and metallurgy it would seem that the use of either iron or copper would depend largely upon the nature and accessibility of the particular deposits, as well as upon the cultural background of the people. Ordinarily, iron can be more readily reduced and worked than copper, while the reduction of bronze requires considerably more skill, and tin, an essential constituent of the alloy, has never been an abundant metal. / Thesis / Master of Arts (MA)