Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. Includes bibliographical references (leaves 105-111).

Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 147-155).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1958. / Typescript. Abstracted in Dissertation abstracts, v. 19 (1958) no. 4, p. 774. "U. S. Geological Survey [preliminary] Open File Report." Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 132-134).

Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 62-64.

A magnetic balance for the measurement of the saturation magnetization of alloys has been designed and built. The magnet develops a field strength of 21,000 oersteds in a gap approximately seven-eighths inch long and two inches in diameter, when consuming a power of 4.5 kilowatts. This field is sufficient to saturate solid metal samples of random shape. Specially shaped pole caps are used which produce a gradient in the direction of the axis of the gap which is constant to within two percent, within a volume cube three-sixteenths of an inch on edge. The ratio of saturation magnetizations of iron and nickel at room temperature agree closely with the accepted values. A new magnetic phase has been discovered in the manganese carbon system. It has been identified as ferromagnetic, but its composition and crystal structure remain unknown. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

The investigation of ferromagnetic phases in the manganese indium, manganese antimony carbon and the manganese magnesium alloy systems was conducted mainly by means of x-ray diffraction methods and where ever permissible by metal1ographic examination. The manganese indium and the manganese antimony carbon alloys were prepared in the vacuum melting furnace in an argon atmosphere, while the manganese magnesium alloys were prepared by sinter-compact techniques. Heat treatments were carried out in tube furnaces in an argon atmosphere. Ferromagnetic phases were not found in either the manganese indium or the manganese magnesium systems. The presence of the compound Mn₃In in the manganese indium system was established. The compound has a gamma brass structure with a lattice parameter a₀ = 9.413 A°. In the manganese magnesium system only solid solutions of manganese and magnesium were found to exist. The manganese solid solution was not magnetic suggesting that the addition of magnesium atoms did not give the degree of separation of manganese atoms for favourable ferromagnetic conditions. It was concluded also that the manganese atoms in the compound Mn₃In were not sufficiently separated for favourable ferromagnetic conditions. The ferromagnetic phase found in the manganese antimony carbon alloys was attributed to the compound Mn₂Sb. This suggested that elements in Group Vb which are strongly electronegative to manganese and form stable binary compounds, do not tend to form ternary compounds containing carbon. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

A dissertation submitted to the Faculty of Engineering, University of Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering Johannesburg, 1991 / The kinetics of reduction of the manganese ore from the Mamatwan mine has been studied by thermogravimetric (TGA) analysis, x-ray diffraction analysis (XRD), optical microscopy, and energy dispersive analysis of x-rays (EDAX) between 1100 and 1350 degree celcius with pure graphite under argon atmosphere. It has been observed that the rate and degree of reduction increased with increasing temperature and decreasing particle size. The effect of the different reaction atmosphere has also been investigated by replacing argon atmosphere with carbonmonoxide (CO) and carbondioxide (C02)' The results clarified importance of some reactions in the reduction mechanism of the ore. In early stages of reduction, up to about 4 minutes of reaction time, carbothermic reduction of higher oxides of manqanase and iron (Mn203 and Fe2o3) to manganeous oxide (MnO) and metallic iron respectively was observed which was controlled by diffusional process across the boundary layer between the solid phases. Apparent activation energy is calculated as 61.03 kJ for this stage which corresponds to about 30 percent reduction. Metallization started as random nucleation of iron rich carbides around Mno grains inside the particle. After 30 percent reduction the formation of a silicate phase was observed. Up to 70 percent reduction at 1350oC, reduction rate was controlled by chemical reaction between oxide phase and gaseous phase with an apparent. activation energy of 153 32 kJ. / MT2017

No description available.

No description available.