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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation Jan 1960

Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation

Publications (WR)

Reservoirs are becoming an increasingly prominent feature of the American landscape. Built for flood mitigation and to change a fluctuating river into a dependable source of water for irrigation, power, and other purposes, they are predestined, like natural lakes, to be destroyed sometime following their creation. Sedimentation sooner or later robs most lakes and reservoirs of their capacity to store water. The significance of sedimentation in the life of Lake Mead, the largest artificial reservoir in the world, was realized when the plan for the reservoir was conceived, and an aerial survey of the floor was made in 1935 before …

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Studies On The Biological Oxidation Of Ferrous Iron And Chalcopyrite, Loral Alvin Decker Aug 1959

Studies On The Biological Oxidation Of Ferrous Iron And Chalcopyrite, Loral Alvin Decker

Theses and Dissertations

The purpose of this investigation was to determine the effectiveness of the leaching streams from waste copper ore dumps as a nutrient solution for subsequent biological oxidation and solubilization of sulfide minerals. The copper in the leaching streams is precipitated by displacement with iron. As a result of this procedure the solution is high in ferrous iron concentration and has a pH of near 3.7. The bacteria in the leaching streams are capable of oxidizing ferrous iron to the ferric state and sulfide minerals to sulfates. The effects of temperatures, pH, urea, and aeration rate on the oxidation of the …

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A Study Of Three Photochemical Activities Of Chloroplasts, Jimmy W. Hinkson Apr 1958

A Study Of Three Photochemical Activities Of Chloroplasts, Jimmy W. Hinkson

Theses and Dissertations

Chloroplasts of sugar beet leaves were subjected to treatment by heating, by incubation at pH 8.5 and pH 5.5, by incubation in ion low water, by sonic oscillation, by digestion with enzymes (lysozyme, pancreatin, and lipase), by extraction with digitonin, and by chemical compounds including 8-hydroxy-quinoline, sodium azide, zinc sulfate, phenyl mercuric acetate, potassium cyanide, 1-allylthiourea, 2,4-dinitrophenol, thymol, and p-chloromercuribenzoate. A comparative study was made of the effects of these treatments upon three photochemical reactions (the photoreduction of 2,6- dichlorophenol indophenol, the photoreduction of indigo carmine in the presence of a couple composed of 2,6-dichlorophenol indophenol and ascorbic acid, and …

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Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson Jul 1957

Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson

Theses and Dissertations

This investigation showed that a single bacterium was capable of sulfide oxidation in exposed ore bodies. This single bacterium was isolated and characterized. It exhibited different characteristics than any previously known organism. It was found to be a chemosynthetic autotroph. An optimum nutrient concentration was determined for pyrite oxidation. The nutrient concentration was determined for pyrite oxidation. The nutrient contains only a source of phosphate and nitrogen. Urea was found to be a better source of nitrogen than ammonium sulfate which had previously been used. The effect of various organic compounds on the oxidation of pyrite was observed. Glucose and …

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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, …

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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 …

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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 …

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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 …

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A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006 Jan 1945

A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006

Electronic Theses and Dissertations

No abstract provided.

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A Study Of The Kjeldahl Method And A Modification For The Determination Of Nitrogen In Alcoholic Distillates., Margie M. Miller Jan 1940

A Study Of The Kjeldahl Method And A Modification For The Determination Of Nitrogen In Alcoholic Distillates., Margie M. Miller

Electronic Theses and Dissertations

No abstract provided.

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