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Full-Text Articles in Physical Sciences and Mathematics

Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson Aug 1956

Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson

Theses and Dissertations

This work represents a study on the biological oxidation of molybdenite, MoS2. The principal objective of this study was to investigate the possibility of the biological oxidation of molybdenite, to determine the physical and chemical conditions under which the oxidative process occurs, and to develop a strain of bacteria or alter the activity of the microorganisms by acclimatization to increase their activity on sulfide minerals, in particular molybdenite. Minerals used in this study were pyrite (FeS2), chalcopyrite (CuFeS2), molybdenite concentrate, and molybdenite ore. The microorganisms used in this investigation were autotrophic bacteria obtained from the leaching streams of Bingham Canyon, …


Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen Jun 1956

Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen

Theses and Dissertations

A study of the photo-oxidation of the 2,6-dichlorophenol indophenol-ascorbic couple was undertaken with a view to investigating the postulated mechanism of oxidation by a component of the oxygen evolving sequence operative in photosynthesis. A spectrophotometric method for the measurement of the progress of photo-oxidation was developed. Temperature and pH dependence were determined and the effect of various common inhibitors and physiological substances tested. None of the common Hill reaction inhibitors were effective in the ascorbic acid photo-oxidation in the system used. KCN and catalase as well as a few other high molecular weight proteins were able to inhibit dark auto-oxidation …


The Chromatographic Purification Of Human Red Blood Cell Acetylcholinesterase, Richard P. Dunkley May 1954

The Chromatographic Purification Of Human Red Blood Cell Acetylcholinesterase, Richard P. Dunkley

Theses and Dissertations

A process of column chromatography of human erythrocyte acetylcholinesterase, using a cationic exchange resin, was investigated as a possible method for the primary partial purification of the enzyme on a large scale. The investigation was based, first; on a detailed study of the enzymatic stability to variation in hydrogen-ion and salt concentrations for periods of time extending to forty eight hours and, second; on an investigation of the degree of adsorption by the resin of the enzyme at various pH values within the pH range of enzyme stability. A method for the analysis of the enzyme activity of large numbers …


Biological Oxidation Of Copper Sulfide Minerals, Delmar Boyd Davis Dec 1953

Biological Oxidation Of Copper Sulfide Minerals, Delmar Boyd Davis

Theses and Dissertations

This work represents a study of the biological oxidation of copper sulfide minerals. The principal objective of the study was to determine the extent of bacterial oxidation on copper containing sulfide minerals. It was also desired to determine if the bacteria could oxidize copper sulfides in the absence of iron. A better understanding of the nitrogen requirements of the organisms was desired. Minerals used in this study were Bingham Canyon Float Concentrate, chalcopyrite, covellite, calcocite, bornite, tetrahedrite, and reagent grade copper sulfide. The bacteria used were obtained from the mine waters of Bingham Canyon, Utah. To study the problem the …