Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2006. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2007 May 30

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Philip C. Bennett. Vita. Includes bibliographical references.

Thesis (M.S.) in Civil Engineering--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 88-93).

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Commercially available boron triiodide (stated to be 99.9% pure) was flash photolysed and found to contain a high level of impurity. After a lengthy purification procedure the sample was still too impure to be of use. Boron triiodide was, therefore, prepared by several methods and shown to be free of impurities by mass spectrometry. A detailed study of these preparative methods has removed many of the ambiguities present in the existing literature. The absorption spectrum of the water sensitive pure B13 vapour was recorded over the range 650-200nm and shown to consist of six absorption maxima ie. transitions to six electronic states of the B13 molecule were detected.

In this research work, three types of flotation models (discrete, mean rate and the gamma function models) are modified based on the relationship between mass recovery and recovery. The modified models can be used to calculate both the recovery and grade of concentrate. Experimental work was carried out by using three different samples, which are chalcopyrite, coal and complex sulphide. In the chalcopyrite and coal flotation, air flow rate (AFR) was varied and different size fractions were considered in coal flotation. In complex sulphide flotation, the impeller speed (IPS) and air flow rate were varied, different size fractions were also considered individually. From the experimental results, the effect of air flow rate, impeller speed and particle size on the recovery and grade of concentrate are obtained, it is shown that an increase in air flow rate does not significantly increase recovery but reduce the grade of concentrate. High impeller speed can increase the recovery of fine and medium size, but it has very little effect on the coarse size. The effect of particle is that the medium size has the highest recovery in Fe minerals but the fine has the highest recovery in Zn and Cu minerals. The air flow rate, impeller speed and particle size affect on the kinetics of flotation is discussed from the model results. Where the modified models are used, the results show that an increase in air flow rate will increase the flotation rate of all size fraction, but an increase in impeller speed can only increase the flotation rate of the fine and medium size. The medium size has the highest flotation rate in most of the case.