Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Life Sciences

PDF

Institution
Keyword
Publication Year
Publication
Publication Type

Articles 36391 - 36420 of 36616

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 Sixty-Eighth Session Of The Iowa Academy Of Science And The Twenty-Third Convention Of The Iowa Junior Academy Of Science, April 20-21, 1956, Iowa Academy Of Science Apr 1956

The Sixty-Eighth Session Of The Iowa Academy Of Science And The Twenty-Third Convention Of The Iowa Junior Academy Of Science, April 20-21, 1956, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Arretotherium Fricki, A New Miocene Anthracothere From Nebraska, J. R. Macdonald, C. Bertrand Schultz Jan 1956

Arretotherium Fricki, A New Miocene Anthracothere From Nebraska, J. R. Macdonald, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

A new species of middle Miocene (early Hemingfordian) anthraco-there, Arretotherium fricki Macdonald and Schultz is described based on a cranium from the upper Marsland deposits of Nebraska. The holotype suggests that this genus was derived from the Oligocene genus Elomeryx Marsh.


Tannin Content Of English Walnuts : Thesis ..., Joseph G. Natoli Jan 1956

Tannin Content Of English Walnuts : Thesis ..., Joseph G. Natoli

University of the Pacific Theses and Dissertations

Present methods for the production of leather from animal hides still depend from the most part on the use of natural tannin extracts. During the year, 1952, the amount of natural tannin extracts used by the leather industry was 560,452,119 pounds as compared to 35,793,000 pounds of synthetic tanning materials. It is not as yet possible to produce synthetic materials as economically as the natural extracts; the result being that there is still a very great demand for natural tannin extracts. The need for finding new domestic sources of tannins is apparent when the amounts of domestic and imported extracts …


Classification Of Oligocene Sediments In Nebraska: A Guide For The Stratigraphic Collecting Of Fossil Mammals, C. Bertrand Schultz, Thompson M. Stout Jun 1955

Classification Of Oligocene Sediments In Nebraska: A Guide For The Stratigraphic Collecting Of Fossil Mammals, C. Bertrand Schultz, Thompson M. Stout

Bulletin of the University of Nebraska State Museum

The Chadron and Brule formations constitute the White River Group in Nebraska and adjacent states. The Brule is divided into the Orella and Whitney members. The latter members are referred to the Medial and Late Oligocene (equivalents of the European Stampian and Aquitanian), while-the Chadron is equated with the Early Oligocene (Sannoisian). Each unit in Nebraska is subdivided into three parts (Lower, Middle, and Upper; or A, B, and C for the Chadron and Whitney, and A-B, C, and D for the Orella). Key beds such as fossil soils (paleosols), Purplish White beds, and volcanic ash layers, when considered with …


The Sixty-Seventh Session Of The Iowa Academy Of Science And The Twenty-Second Convention Of The Iowa Junior Academy Of Science, April 15-16, 1955, Iowa Academy Of Science Apr 1955

The Sixty-Seventh Session Of The Iowa Academy Of Science And The Twenty-Second Convention Of The Iowa Junior Academy Of Science, April 15-16, 1955, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Paleosols Of The Oligocene Of Nebraska, C. Bertrand Schultz, Lloyd G. Tanner, Cyril Harvey Mar 1955

Paleosols Of The Oligocene Of Nebraska, C. Bertrand Schultz, Lloyd G. Tanner, Cyril Harvey

Bulletin of the University of Nebraska State Museum

Prominent paleosol ("buried" or "fossil" soil) complexes occur at the top of the middle Orella, upper Orella, lower Whitney, and upper Whitney in the Brule formation of Nebraska; and at the top of the "Lower Oreodon," "Middle Oreodon," "Upper Oreodon," and "Leptauchenia" beds in the Brule deposits of South Dakota. These paleosols have regional distribution and appear to be of value in stratigraphic correlations. Major faunal breaks seem to coincide with important buried soil zones, thus indicating that certain paleosols actually represent unconformities. Some of the soils were developed on old land surfaces where deposition was practically at a standstill …


Amount And Chemical Composition Of The Organic Matter Contributed By Overstory And Understory Vegetation To Forest Soil, David Robert Main Scott Jan 1955

Amount And Chemical Composition Of The Organic Matter Contributed By Overstory And Understory Vegetation To Forest Soil, David Robert Main Scott

Yale School of the Environment Bulletin Series

No abstract provided.


Age And Length Of Menhaden (Brevoortia Tyrannus) In The Waters Of Chesapeake Bay, With Comments On The Rate Of Growth, Ray T. Oglesby Jan 1955

Age And Length Of Menhaden (Brevoortia Tyrannus) In The Waters Of Chesapeake Bay, With Comments On The Rate Of Growth, Ray T. Oglesby

Dissertations, Theses, and Masters Projects

No abstract provided.


Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall Jan 1955

Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall

Biological Sciences Faculty Publications

Continual sand deposition on the Lake Erie shore, adjacent to the mouth of the Grand River, has led to the formation of a developing sand dune community and through the years a successional pattern of plant growth. An analysis was made of the general plant composition of the area by means of four transects directed from the bare beach inland. Definite zonation of specific plant species was present throughout the community in parallel formation. Named for the dominant plant types they contained, the major stages were: dune grass, poplar, aspen, and oak.


38th Annual Meeting, 1954. Secretary's Report, Lowell F. Bailey Jan 1955

38th Annual Meeting, 1954. Secretary's Report, Lowell F. Bailey

Journal of the Arkansas Academy of Science

No abstract provided.


38th Annual Meeting, 1954. Program, Academy Editors Jan 1955

38th Annual Meeting, 1954. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


38th Annual Meeting, 1954. Abstracts Of Papers, Academy Editors Jan 1955

38th Annual Meeting, 1954. Abstracts Of Papers, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Abstract Papers May 1954

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Abstract Papers May 1954

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Abstract Papers May 1954

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


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 …


The Sixty-Sixth Session Of The Iowa Academy Of Science And The Twenty-First Convention Of The Iowa Junior Academy Of Science, April 30 And May 1, 1954, Iowa Academy Of Science Apr 1954

The Sixty-Sixth Session Of The Iowa Academy Of Science And The Twenty-First Convention Of The Iowa Junior Academy Of Science, April 30 And May 1, 1954, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Properties Of American Beech In Tension And Compression Perpendicular To The Grain And Their Relation To Drying, Eric L. Ellwood Jan 1954

Properties Of American Beech In Tension And Compression Perpendicular To The Grain And Their Relation To Drying, Eric L. Ellwood

Yale School of the Environment Bulletin Series

No abstract provided.


The Effect Of Synthetic Resin Adhesives On The Strength And Physical Properties Of Wood Veneer Laminates, Stephen B. Preston Jan 1954

The Effect Of Synthetic Resin Adhesives On The Strength And Physical Properties Of Wood Veneer Laminates, Stephen B. Preston

Yale School of the Environment Bulletin Series

No abstract provided.


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 …


Economic Analysis Of Forage Production And Utilization In Dakota And Dixon Counties, Nebraska, Howard W. Ottoson Nov 1953

Economic Analysis Of Forage Production And Utilization In Dakota And Dixon Counties, Nebraska, Howard W. Ottoson

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

Soil erosion remains a serious problem on many Nebraska farms despite programs of financial assistance, technical aid, and education by several national and state agencies. One reason that soil conserving adjustments in land use have not been made by farmers is that considerable uncertainty surrounds the economics of soil erosion control on the farm level. This study is an attempt to increase knowledge and reduce some of the uncertainty with regard to the economics of erosion control in a specific area.


Abstract Papers May 1953

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Abstract Papers May 1953

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Commercial Fertilizers For Winter Wheat In Relation To The Properties Of Nebraska Soils, R. A. Olson, H. F. Rhoades Jan 1953

Commercial Fertilizers For Winter Wheat In Relation To The Properties Of Nebraska Soils, R. A. Olson, H. F. Rhoades

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

It is the purpose of this bulletin to report the investigations that have been made correlating soil properties and fertilization practices with yields of winter wheat. Since the success or failure of fertilization practices is so dependent on specific soil conditions, an attempt has been made here to further characterize the major soils of the different sections of the state which are devoted to wheat production and to analyze fertilizer practices and results in relation to the soil properties determined. The data are summarized for the four sections of the state designated as southeastern, east-south-central, west-south-central and western Nebraska. These …


Taxation And Other Factors Affecting Private Forestry In Connecticut, Eugene V. Zumwalt Jan 1953

Taxation And Other Factors Affecting Private Forestry In Connecticut, Eugene V. Zumwalt

Yale School of the Environment Bulletin Series

No abstract provided.


Drying Rates Of Thin Sections Of Wood At High Temperatures, Herbert O. Fleischer Jan 1953

Drying Rates Of Thin Sections Of Wood At High Temperatures, Herbert O. Fleischer

Yale School of the Environment Bulletin Series

No abstract provided.


Ionic Exchange In Soils: I. Measurement Of The Exchange Reaction By Means Of An Ion Exchange, D. A. Brown Jan 1953

Ionic Exchange In Soils: I. Measurement Of The Exchange Reaction By Means Of An Ion Exchange, D. A. Brown

Journal of the Arkansas Academy of Science

No abstract provided.


An Annotated List Of The Orthoptera Of Nebraska Part Ii The Tettigidae And Acrididae, Harold A. Hauke Jan 1953

An Annotated List Of The Orthoptera Of Nebraska Part Ii The Tettigidae And Acrididae, Harold A. Hauke

Bulletin of the University of Nebraska State Museum

This is the second of a series of papers on the Orthoptera of Nebraska. It is a continuation of the revision of an unpublished thesis on this subject by the author in 1934.