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Articles 77791 - 77820 of 78522
Full-Text Articles in Entire DC Network
Proceedings Of A Symposium: Pollution Control Of Industrial Wastewaters, Calvin K. Sudweeks, Lynn M. Thatcher, Elmo Morgan, Franklin J. Agardy, R. E. Pailthorp, John C. Merrell Jr.
Proceedings Of A Symposium: Pollution Control Of Industrial Wastewaters, Calvin K. Sudweeks, Lynn M. Thatcher, Elmo Morgan, Franklin J. Agardy, R. E. Pailthorp, John C. Merrell Jr.
Reports
No abstract provided.
Time And Soil Development On Lateral Moraines, Martin River Glacier, South-Central Alaska, John R. Tinker Jr.
Time And Soil Development On Lateral Moraines, Martin River Glacier, South-Central Alaska, John R. Tinker Jr.
Theses and Dissertations
During the summer of 1966, eighteen soil profiles on a series of 21 lateral moraines, were studied to ascertain the relationship of time to soil development. The moraines are located on Charlotte Ridge on the south margin of the Martin River Glacier in south-central Alaska. The elevation of the highest moraine is approximately fifteen hundred feet and is located 800 feet above the present level of the glacier.
To determine the direct effect of time on soil formation, the remaining soil forming factors were kept constant; the soil pits were located so that relief, exposure, and vegetation of the sites …
Studies In Coprecipitation Of Trace Amounts Of Elements, Gerald Delano Schucker
Studies In Coprecipitation Of Trace Amounts Of Elements, Gerald Delano Schucker
Masters Theses
"A new approach to preconcentration of trace amounts of elements has been demonstrated whereby traces of metals tied up as chelates are coprecipitated on a column of solid organic material. Complete coprecipitation was found to occur within very narrow pH ranges, thereby allowing separation as well as concentration of the elements by careful adjustment of acidity and concentration of chelating agent. The separation is based on the difference in stability constants of the metal chelates. Preliminary studies with different physical forms of the carrier precipitate, indicate adsorptive processes could play a significant role in the mechanism of the column-coprecipitation process. …
The Acidic Transformaion Products Of Indoles Formed By Basidiomycetes, Chung-Ke Chang
The Acidic Transformaion Products Of Indoles Formed By Basidiomycetes, Chung-Ke Chang
Masters Theses
"A survey of the ability of basidiomycetes to convert tryptophan, tryptamine and indole acetic acid to other acidic indoles has been made.
The product formed from tryptamine by Tricholoma nudum was identified as indole acetic acid. The product formed by Cantharellus cibarius from D-tryptophan was identified as N-acetyl-D-tryptophan. The products were purified and identified by means of paper chromatography, thin layer chromatography, infrared spectroscopy and melting points.
The conversion of tryptamine and D-tryptophan was also studied in cultures of Leucopaxillus paradoxus, Hygrophorus conicus and Naucoria confragosa. H. conicus, L. paradoxus and N. confragosa transformed tryptamine and indole acetic acid into …
Recent Fluvial Geology In Western North Dakota, Thomas M. Hamilton
Recent Fluvial Geology In Western North Dakota, Thomas M. Hamilton
Theses and Dissertations
The thesis here abstracted was written under the direction of Lee Clayton and approved by Walter L. Moore -and John R. Reid as members of the examining connnittee, of which Mr. Clayton was chairman.
In western North Dakota many drainage channels that are incised into valley fill are characterized by steep, unvegetated sides. Many such channels contain actively eroding scarps. The origin of these scarps is most frequently related to increased water velocity causing accelerated erosion on a steepened reach of the valley flat.
The principal mechanism of scarp migration is soilfall which is initiated by undercutting of the scarp …
Theory Of Rbe For Heavy Ion Bombardment Of Dry Enzymes And Viruses, J. J. Butts, Robert Katz
Theory Of Rbe For Heavy Ion Bombardment Of Dry Enzymes And Viruses, J. J. Butts, Robert Katz
Robert Katz Publications
The response of dry enzymes and viruses to heavy ion bombardment may be predicted from their response to γ-irradiation (and no further knowledge of their size and structure). The molecules are approximated as point particles whose response to ionization is the same for heavy ion bombardment as for γ-rays. From the δ-ray distribution formula and an extrapolated range-energy relation for electrons, the radial distribution of secondary ionization energy may be found. Under this dosage distribution the inactivation probability may be found as a function of radial distance from the ion's path, and then may be integrated over all space to …
A Geographical Interpretation Of Coles County Soils Through A Comparative Analysis Of Modern Soil Classification Systems, John C. Klink
A Geographical Interpretation Of Coles County Soils Through A Comparative Analysis Of Modern Soil Classification Systems, John C. Klink
Masters Theses
No abstract provided.
Sur La Faculté D'Absorption De Substances Colorées Par La Cuticule De Caecosphaeroma Burgundum Dollfus, Crustacé Isopode Des Eaux Souterraines, François Graf, Claude Marvillet
Sur La Faculté D'Absorption De Substances Colorées Par La Cuticule De Caecosphaeroma Burgundum Dollfus, Crustacé Isopode Des Eaux Souterraines, François Graf, Claude Marvillet
International Journal of Speleology
The discovery, in certain subterranean waters, of “pigmented,” brown or black Caecosphaeroma burgundum, led to the systematic study of the action of pigmented substances on these crustaceans. The results of these experiments demonstrate that the colorations thus obtained or observed in nature are due to the agglutination of coloured substances on the surface of the carapace and, in certain cases, to an impregnation of the cuticle itself.
The Technique Of Lineaments And Linears Analysis And Its Application In The Minerogenic Province Of Southeast Missouri, Hassan A. Etr
The Technique Of Lineaments And Linears Analysis And Its Application In The Minerogenic Province Of Southeast Missouri, Hassan A. Etr
Doctoral Dissertations
"Current terminology in the field of lineaments and linears (lineations) analysis was reviewed and quantitative definitions of the common terms offered. A general classification of lineations is herein proposed. Characteristics of drainage and airphoto lineations were reviewed and the procedure used in their analysis discussed.
An area about 1880 square miles was analyzed for lineations based on drainage networks and the resulting patterns showed preferred orientation. These drainage lineations were later compared with the airphoto lineations of the same area and a limited degree of similarity was observed.
The airphoto lineations of an area approximately 7000 sq. mi. covering the …
A New Species Of Gomphonema (Bacillariophyta) From Mammoth Cave, Kentucky, Sam L. Van Landingham
A New Species Of Gomphonema (Bacillariophyta) From Mammoth Cave, Kentucky, Sam L. Van Landingham
International Journal of Speleology
In some materials collected from Mammoth Cave, Kentucky, a diatom was found which could not be identified with any known species. A taxonomic description of Gomphonema hotchkissii nov. spec. is given.
Die Ökologische Stellung Der Höhlen-Und Spaltengewässer Innerhalb Der Subterranaquatilen Lebensbereiche, Siegfried Husmann
Die Ökologische Stellung Der Höhlen-Und Spaltengewässer Innerhalb Der Subterranaquatilen Lebensbereiche, Siegfried Husmann
International Journal of Speleology
Bodies of waters in caves and in crevices of rocks are distinguished from the other subsoil water ecosystems (“eustygon”, “stygorhithron”, “stygopotamon”) under the names “troglostygon” and “petrostygon”. The colonisation of subsoil water biotopes involves a fundamental principle which controls the development of the main biotopes for the stygobiont undergroundwater organisms. According to this ecological rule, which is described in detail and formulated, the several interstitial biotopes (for example “eustygopsammal,” “rhithrostygopsammal,” “potamostygopsephal”) are to be considered as the real biotopes of the stygobiont subsoil water organisms; waters in caves, on the contrary, are secondary biotopes of these animals. Caves which contain …
Mise En Evidence De Substances Fluorescentes Dans Les Organes Jaunes De Caccosphaeroma Burgundum Dollfus, Crustacé Isopode Des Eaux Souterraines, H. Descimon, C. Marvillet
Mise En Evidence De Substances Fluorescentes Dans Les Organes Jaunes De Caccosphaeroma Burgundum Dollfus, Crustacé Isopode Des Eaux Souterraines, H. Descimon, C. Marvillet
International Journal of Speleology
Chromatographic analysis of the yellow organs of the fresh-water Isopod Crustacean Caecosphaeroma burgundum Dollfus revealed, through observation of the chromatograms in ultraviolet light, the occurrence of both absorbing and fluorescent substances. Among the latter, only isoxanthopterin has been identified. The yellow pigment, which probably has a pteridine nucleus, could not be identified as a known compound and will be the object of later investigations.
Analyse Du Comportement Alimentaire Du Poisson Cavernicole Aveugle Anoptichthys Gen. Et D'Hybrides F1 (Astyanax X Anoptichthys) Et F2, Georges Thines, Monique Soffie, Erik Vandenbussche
Analyse Du Comportement Alimentaire Du Poisson Cavernicole Aveugle Anoptichthys Gen. Et D'Hybrides F1 (Astyanax X Anoptichthys) Et F2, Georges Thines, Monique Soffie, Erik Vandenbussche
International Journal of Speleology
The feeding behaviour of the blind cave fish Anoptichthys is characterised by two phases, an initial short chemioreceptic one and second one in which the fish explores the bottom systematically for a longer period. The whole process last approximately 30 seconds, both in adults as in youngsters.
Algal Growth Experiments In The Baradla Cave At Aggtelek (Biospeleologica Hungarica Xxi), Erzsebet Kol
Algal Growth Experiments In The Baradla Cave At Aggtelek (Biospeleologica Hungarica Xxi), Erzsebet Kol
International Journal of Speleology
The author kept 108 algal strains (Cyanophyta 53, Chlorophyta 35, Chrysophyta 20), of axenic cultures from the Kol-Algotheca in the Botanical Division of the Hungarian National Sciences Museum in the Baradla Cave, at Aggletek (Hungary) in darkness for 204-420 days under different environmental conditions. The experiments have proven that several algal strains can tolerate well the complete absence of light. Furthermore, that some algal strains show intensive development even under such conditions. These axenic cultures kept in the cave in metal boxes on inorganic medium have shown that the energy source used by these green coloured algae is not …
Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Ii, Thomas Barrett
Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Ii, Thomas Barrett
Green Revolution
Reprint of section of book Earthworms by Thomas Barrett.
The Study Of The Metal Complexes Of Alpha Aminohydroxamic Acids, Richard N. Nipe
The Study Of The Metal Complexes Of Alpha Aminohydroxamic Acids, Richard N. Nipe
Masters Theses
Introduction
The objectives of this investigation were to develop: 1) compounds similar to hydroxy urea, a compound known to have anti-tumor activity, 2) a method to prepare α-aminohydroxamic acids and to study the complexes of these compounds with several metal ions, 3) computer programs to determine the pK's1 of the hydroxamic acids and the stepwise stability constants2 for the ligands and several metal ions.
The values obtained for the stability constants were compared with values for the stability constants of acetohydroxamic acid and α-aminocarboxylic acids in an attempt to find which in the ligand formed bonds with the …
Blackbird Damage And Control--An Informal Seminar, M. I. Dyer
Blackbird Damage And Control--An Informal Seminar, M. I. Dyer
Bird Control Seminars Proceedings
The object is to hash over a few problems as we see them on this red-winged blackbird situation. I'm Mel Dyer, University of Guelph, Guelph, Ontario. Around the table are Tom Stockdale, Extension Wildlife Specialist, Ohio Cooperative Extension Service, Columbus; Maurice Giltz, Ohio Agriculture Research and Development Center, Wooster, Ohio; Joe Halusky, U.S. Fish and Wildlife Service, Columbus, Ohio; Daniel Stiles, U.S. Fish and Wildlife Service, Washington, D.C.; Paul Rodeheffer, U.S. Fish and Wildlife Service, Columbus, Ohio; Brian Hall, Blackbird Research Project, University of Guelph, Guelph, Ontario; George Cornwell, Virginia Polytechnic Insti¬tute, Blacksburg, Va.; Dick Warren, Peavey Grain Company, Minneapolis, …
Bird Control Methods And Devices--Comments Of The National Pest Control Association, Philip J. Spear
Bird Control Methods And Devices--Comments Of The National Pest Control Association, Philip J. Spear
Bird Control Seminars Proceedings
It may be useful to review some of the considerations that go into recommendations concerning bird management. Later I will make some comments concerning specific methods and devices being used in or promoted for bird control work regardless of whether or not they are new. Members of the National Pest Control Association provide a variety of services, such as fumigation, termite control and general pest control which includes rodent control. There are eight such categories listed in our roster, but only one member in five provides every service listed. Bird control is a rather recent development and is the newest …
Blackbird Flock Behavior In Corn, A Theoretical Model (With Session Discussion), M. I. Dyer
Blackbird Flock Behavior In Corn, A Theoretical Model (With Session Discussion), M. I. Dyer
Bird Control Seminars Proceedings
I realized this past winter that redwings form the base for an international problem, and so I went down to see Jim Caslick in Florida. Unfortunately, I picked the wrong season. I misjudged the weather for when I went down in May to get experimental birds it was pretty hot. Next year I'll be a bit more careful and go down during the winter time. I want to discuss something a bit different but still in line with crop damage by red-winged blackbirds. I want to relate the damage assessment that we're making in agricultural corn to bird behavior. We've …
Agricultural Bird Problems In The West, Donald Balser
Agricultural Bird Problems In The West, Donald Balser
Bird Control Seminars Proceedings
First, I'd like to qualify geographically, the area where most of our work is done and problems occur. It is primarily in the Rocky Mountain states and the west coast. While the area of the Denver Wildlife Research Center's responsibility covers the states west of the Mississippi River; the only area on the plains where our personnel have conducted intensive studies outside of Colorado is in South Dakota. The major bird problems in grain crops in the west are primarily caused by blackbirds excepting, of course, waterfowl depredations. It's difficult to rank the principal crops according to seriousness of losses. …
Frontmatter & Opening Remarks, 3rd Bird Control Seminar, William B. Jackson
Frontmatter & Opening Remarks, 3rd Bird Control Seminar, William B. Jackson
Bird Control Seminars Proceedings
Bowling Green State University, Bowling Green, Ohio, September 13-15, 1966.
Sponsored by the Department of Biology, Bowling Green State University, with the assistance of Division of Wildlife Services, United States Fish and Wildlife Service, and the National Pest Control Association, Elizabeth, New Jersey.
Dr. William B. Jackson, Conference Chairman; David E. Schneider, Conference Assistant; David E. Schneider and William B. Jackson, Editors.
Ecological Control Of Bird Hazard To Aircraft, V. E. F. Solman
Ecological Control Of Bird Hazard To Aircraft, V. E. F. Solman
Bird Control Seminars Proceedings
The Canadian Wildlife Service has had twenty-five years experience with the problem caused by bird contacts with aircraft. I experienced my first bird strike, while flying as an observer on a waterfowl survey in August, 1940. Officers of the Service investigated bird problems at airports at Yarmouth, Nova Scotia, and Cartierville, Quebec, in the late 1940's. Those incidents involving gulls and low speed piston-engined aircraft caused minor damage to the aircraft but considerable disturbance to the operators. As aircraft speeds increased and airports became more numerous and busier the problem increased in extent and complexity. By 1960 it was apparent …
Host And Prophage Modifications Of Ultraviolet Induction In Salmonella Potsdam, Bela B. Toth
Host And Prophage Modifications Of Ultraviolet Induction In Salmonella Potsdam, Bela B. Toth
Loma Linda University Electronic Theses, Dissertations & Projects
In induction experiments with naturally occurring and artificially lysogenic strains of S. potsdam, cells were irradiated in buffer, transferred to complete medium, and then assayed for free phage. Irradiation was followed by half hourly samples for free phage from the growing populations of irradiated cells. For an estimation of burst sizes, the irradiated cells were diluted out to a final concentration of 1 cell per ml and distributed to tubes in 0.5 ml quantities. All assays were done by the top-layer method with streptomycin incorporated in the top-layer and SP2-strr as the bacterial indicator. The non-lysogenic strain S. …
The Synthesis Of Pyridazines, Cinnolines, Tetrazines, Tetrazapyrenes And Related Nitrogen Heterocycles, William D. Guither
The Synthesis Of Pyridazines, Cinnolines, Tetrazines, Tetrazapyrenes And Related Nitrogen Heterocycles, William D. Guither
Chemistry and Chemical Biology ETDs
There are many examples of nitro-substituted aromatic compounds, and of these the compounds in the benzene series have been most extensively studied. Nitro groups attached to an aromatic ring vary in reactivity toward nucleophilic displacement. For example, when two nitro groups are ortho or para to each other, one may be substituted with varying ease depending on the other substituents present. Nitro groups which are meta to one another are generally not subject to nucleophilic displacement. The mobility or ease of displacement of a nitro group by a nucleophile may be increased by introduction of other groups into the ring, …
Isolation Of A Toxic Substance From Centaurea Repens, Merton E. Sprengel
Isolation Of A Toxic Substance From Centaurea Repens, Merton E. Sprengel
Loma Linda University Electronic Theses, Dissertations & Projects
A poisonous steroid-type compound was isolated from Centaurea repens. After extraction with absolute ethanol, removal of the solvent, addition of 2% HCl to precipitate the pigments, and filtering, the pH was adjusted to 9 with aqueous anunonia. This solution was exhaustively extracted with chloroform, evaporated to dryness, and extracted with ethyl ether.
This fraction was chromatographed on silica-gel plates, using 10:1 1,2-dichloroethane-methanol as the developer. The band at Rf 4.2 was removed and found toxic to mice. Labored, slow, gasping respiration and frequent involuntary muscular contractions became apparent within a few minutes following the intraperitoneal injection into each animal. Death …
Acquisition Of Health Knowledge In Selected Hong Kong Secondary Schools, Anne D. Lindt
Acquisition Of Health Knowledge In Selected Hong Kong Secondary Schools, Anne D. Lindt
Loma Linda University Electronic Theses, Dissertations & Projects
The exploratory survey method was used to determine the extent to whole scientific knowledge, related to principles and practices of healthful living, was enhanced during the secondary school education of students attending four Seventh-day Adventist secondary schools in Hong Kong. The tool, in the form of a health knowledge test designed to fit the cultural patterns of the population, was applied to 358 Form I (grade 7) and Form V (grade 11) students of the specified schools. Individual scores were computed and comparative analyses done on scores of groups of students representing the two different educational levels, sex differences, two …
The Cleavage Of Diborane By Tetra (Dimethylamino)Diboron And The Preparation Of Some Dihale (1, 10-Phenanthroline)Boron(Iii) Cations, Jack D. Cummins
The Cleavage Of Diborane By Tetra (Dimethylamino)Diboron And The Preparation Of Some Dihale (1, 10-Phenanthroline)Boron(Iii) Cations, Jack D. Cummins
Chemistry and Chemical Biology ETDs
Boron hydrides were first described and characterized by Stock (1). His early work has led to the proposal of about twenty new, distinctly identifiable hydrides (2). Of the proposed hydrides, it has been established that diborane-6 (B2H6), tetraborane-10 (B4H10), and nonaborane-15 (B9H15) contain bridged BH2 groups in the boron hydride framework (2,3,4,5,6,7,8,9). The proposed structures for these compounds is shown in fig. 1 (2,10).
Potential Neoplasm Inhibitors Ii, Ronald Lee Floyd
Potential Neoplasm Inhibitors Ii, Ronald Lee Floyd
Master's Theses
No abstract provided.
Development, Verification, And Use Of Methods To Model Chemical And Thermal Processes Lakes Mead And Powell, Bureau Of Reclamation
Development, Verification, And Use Of Methods To Model Chemical And Thermal Processes Lakes Mead And Powell, Bureau Of Reclamation
Publications (WR)
PURPOSE The purpose of the proposed research is to quantify the effects that Lakes Mead and Powell have on the salinity in the Colorado River system, and to evaluate changes that cap be made to the operating system of the reservoirs (within legal/institutional constraints) to enhance salt precipitation and/or minimize evaporation within the reservoirs. The effect of any changes (i.e., selective withdrawal uses, pumped storage, etc.) on reservoir evaporation could also be evaluated with a goal of minimizing evaporation. This will be accomplished through the development of a mathematical model of the reservoirs as described below. BACKGROUND Two major problems …
Liquid Scintillators. The Stability Of Organic Scintillator Solutes Toward Ultra-Violet Radiation. The Photooxidation Of 2, 5-Diphenyloxazole, Harold A. Mackay
Liquid Scintillators. The Stability Of Organic Scintillator Solutes Toward Ultra-Violet Radiation. The Photooxidation Of 2, 5-Diphenyloxazole, Harold A. Mackay
Chemistry and Chemical Biology ETDs
An insight has been gained concerning the stability of organic scintillator solutes in toluene on exposure to ultraviolet light while in the presence of oxygen and water. Oxygen and water, from either solute or solvent, not only function as quenchers but may continue to react with the solute molecule via a photooxidation process. Removal of these materials from the 2, 5-diphenyloxazole toluene system resulted in a marked improvement in stability of the system on exposure to ultraviolet light. The choice of scintillator solute, in addition to water and oxygen, and the time of ultraviolet irradiation, has a pronounced effect on …