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Articles 77731 - 77760 of 78523
Full-Text Articles in Entire DC Network
Multiple Cropping Will Increase The Erosion Hazard, W J. Burdass
Multiple Cropping Will Increase The Erosion Hazard, W J. Burdass
Journal of the Department of Agriculture, Western Australia, Series 4
WITH the low price of wool and the price of wheat high in comparison, farmers need little encouragement to increase their acreage of crops.
Unfortunately with increased cropping comes the risk of increased erosion—unless there is a simultaneous increase in the use of conservation practices.
The Dispersing Power Of Oxidized Starches On Aqueous Pigment Suspensions, Louis K. Wilhelm
The Dispersing Power Of Oxidized Starches On Aqueous Pigment Suspensions, Louis K. Wilhelm
Masters Theses
No abstract provided.
Cyclic Derivatives Of 2-Amino-2-Deoxy-D-Hexopyranoses, Kenji Miyai
Cyclic Derivatives Of 2-Amino-2-Deoxy-D-Hexopyranoses, Kenji Miyai
University of the Pacific Theses and Dissertations
The purpose of this investigation was to prepare heterocyclic derivatives, bridging C-2 and C-3 of 2-amino-2-deoxy-D-hexopyranoses, useful as blocking groups in the preparation of aminosugar oligosaccharides and polysaccharides. The work reported herein is concerned with oxazolidones of 2-amino-2-deoxy-D-hexopyranoses (Figure 1).)
There are no examples known, in which five or six-membered rings are fused in a trans-arrangement to five-membered furanose ring. However, although synthetic difficulties were observed, sic and five-membered rings were fused in a trans-arrangement to a sic-membered pyranose ring as pointed out before. In the case of our trans-diequatorially fused oxazolidones additional preparative difficulties were expected, because of the …
Endogenous Metabolism Of Polyporus Sulfureus. : Utilization Of Exogenous Carbohydrates And Fatty Acids, Shu-Mei Wang
Endogenous Metabolism Of Polyporus Sulfureus. : Utilization Of Exogenous Carbohydrates And Fatty Acids, Shu-Mei Wang
Masters Theses
"A strain of Polyporus sulfureus from the collection at the University of Missouri at Rolla was used in this investigation. Organisms of this genus have been reported to produce eburicoic acid in good yield and this was confirmed for the organism used in this study by the isolation and identification of eburicoic acid from the mycelium. Growth studies of this organism showed that 4% malt extract is a better medium than synthetic media containing asparagine, nitrate or nitrate plus 0.5% yeast extract as nitrogen sources. An examination of the pH of the culture medium led to the conclusion that regardless …
Properties And Structure Of Some Chalcogenide Glasses, Amin Ismail Amin Abdel-Latif
Properties And Structure Of Some Chalcogenide Glasses, Amin Ismail Amin Abdel-Latif
Archived Theses and Dissertations
No abstract provided.
Catalytic Decomposition Of Hydrogen Peroxide By Manganese-Doped Magnesium Hydroxide, Nabih Philobbos Kelada
Catalytic Decomposition Of Hydrogen Peroxide By Manganese-Doped Magnesium Hydroxide, Nabih Philobbos Kelada
Archived Theses and Dissertations
No abstract provided.
The Postglacial Sedimentology Of Devils Lake, North Dakota, Edward Callender
The Postglacial Sedimentology Of Devils Lake, North Dakota, Edward Callender
Theses and Dissertations
The present sedimentary environment of Devils Lake, a Closed brackish lake in northeastern North Dakota, was investigated, and changes in the Holocene lacustrine environment are interpreted. Sediment samples from Main Bay of Devils Lake were analyzed for their physical, chemical and mineral ogical properties. Analytical data on surface sedimer.t were used to delineate the present sedimentary environment, while data on sediment from three cores were used to reconstruct the Holocene lacustrine history.
The dominant physical processes affecting the surface sediment are wave action and intermittent sediment influx through Big Coulee. The dominant chemical process, precipitation of calcium carbonate, is a …
Urban Geology—A Need And A Challenge, William J. Wayne
Urban Geology—A Need And A Challenge, William J. Wayne
Department of Earth and Atmospheric Sciences: Faculty Publications
Urban land uses are rapidly converting open land into intensively used land. Generally, in planning those uses, a comprehensive study has included everything except an evaluation of the land in three dimensions. Geologists are eminently well equipped to supply the missing data, but they must also be aware of the needs of the urban community and the kinds of information needed by planners if they are to write reports usable by planners. Urban and environmental geology is a newly expanding field in the use of geologic data to help solve some urban problems in the planning stage. It is likely …
An Investigation Of The Feasibility Of Making Radiometric Titrations Of Precipitation Reactions, Harold Elmore Hammerstrom
An Investigation Of The Feasibility Of Making Radiometric Titrations Of Precipitation Reactions, Harold Elmore Hammerstrom
University of the Pacific Theses and Dissertations
The purpose of the present work was to (1) determine the feasibility of performing radiometric titrations using low activity radioisotopes and inexpensive equipment; (2) develop a workable procedure for performing ·radiometric titrations in the classroom; and (3) assemble the basic radioactive concepts needed so the content could be used in a chemistry course of study.
The limited work done previously with radiometric titrations has used solutions of high specific activity and relatively large volumes of solution. The use of high activity radioisotopes creates problems of radioisotope procurement, shielding, handling and disposal. The use of high activity radioisotopes required special training …
Determination Of Flow Curves From Capillary Rise Rate Measurements, Richard Lehr Kissling
Determination Of Flow Curves From Capillary Rise Rate Measurements, Richard Lehr Kissling
University of the Pacific Theses and Dissertations
The measurement of viscosity is a common and useful technique for investigating the mechanical behavior of many real fluids. Theoretical interpretations of viscosity measurements have been important in attempts to elucidate fundamental properties of the liquid state. Brush (6) and Bondi (3) give reviews of the current status of attempts to construct theories of liquid viscosity, and it is quite apparent from these reviews that the molecular theory of rheological phenomena is in its infancy.
In addition to the fundamental aspects of viscometry, there are many practical applications to which viscosity measurements are directed (25). One has only to scan …
Measurement Of Fluorescence Lifetimes Of Biologically Significant Compounds, Irene Adele Petz
Measurement Of Fluorescence Lifetimes Of Biologically Significant Compounds, Irene Adele Petz
University of the Pacific Theses and Dissertations
The purpose of this research was to measure fluorescence decay-times of several biologically significant compounds. Although various equations are available which permit one to calculate fluorescence lifetimes from spectral data, ample evidence exists which indicates such calculations are at considerable variance with experimental results.
Mechanical Effects Of Acoustic Transients On Tobacco Mosaic Virus, Philip Edward Hamrick
Mechanical Effects Of Acoustic Transients On Tobacco Mosaic Virus, Philip Edward Hamrick
Theses and Dissertations
The mechanical breakage of tobacco mosaic virus (TMV) due to the action of acoustic transients has been investigated. The acoustic transients were produced by transient heating of a Prussian blue dye solution (attenuation coefficient of 1000 per cm) when a ruby laser light (20 x 106 watts) was incident on the dye surface. A quartz piezoelectric transducer was used to determine the amplitude and form of the acoustic wave. The production of acoustic waves by transient heating is discussed, and the theoretical form of the acoustic wave determined for various boundary and initial conditions are compared to the experimentally …
Sur Une Nouvelle Sous-Espèce De Niphargus Jovanovici Karaman (Crustacea, Amphipoda, Gammaridae) De Dijon, France, François Graf, Milan Straškraba
Sur Une Nouvelle Sous-Espèce De Niphargus Jovanovici Karaman (Crustacea, Amphipoda, Gammaridae) De Dijon, France, François Graf, Milan Straškraba
International Journal of Speleology
The new subspecies, Niphargus jovanovici burgundus n.subsp., is described from a well at Dijon, France. The principal diagnostic characters are given and a comparison with other known subspecies of N. jovanovici is made. Two groups of subspecies in N. jovanovici are distinguished and some critical remarks on probable affinities of N. jovanovici with other species of Niphargus are made.
Ecological Studies In The Mammoth Cave System Of Kentucky, Thomas C. Barr Jr.
Ecological Studies In The Mammoth Cave System Of Kentucky, Thomas C. Barr Jr.
International Journal of Speleology
The Mammoth Cave system includes more than 175 kilometers of explored passages in Mammoth Cave National Park, Kentucky. Although biologists have explored the caves intermittently since 1822, the inventory of living organisms in the system is still incomplete. The present study lists approximately 200 species of animals, 67 species of algae, 27 species of fungi, and 7 species of twilight-zone bryophytes. The fauna is composed of 22% troglobites, 36% troglophiles, 22% trogloxenes, and 20% accidentals, and includes protozoans, sponges, triclads, nematodes, nematomorphs, rotifers, oligochaetes, gastropods, cladocerans, copepods, ostracods, isopods, amphipods, decapods, pseudoscorpions, opilionids, spiders, mites and ticks, tardigrades, millipedes, centipedes, …
The Occurrence And Distribution Of Methane In The Marine Environment, Larry P. Atkinson, Francis A. Richards
The Occurrence And Distribution Of Methane In The Marine Environment, Larry P. Atkinson, Francis A. Richards
CCPO Publications
The distributions of methane dissolved in the sulfide-bearing waters of the Black Sea, the Cariaco Trench, and Lake Nitinat are reported. The gas was not detected in the oxygen-deficient water of the eastern tropical Pacific Ocean, in the Santa Barbara Basin, nor in the sulfide-bearing water of Saanich Inlet. Maximum concentrations observed were 70 μmole CH4/l., and the distribution tends to follow that of sulfide. The data indicate that methane is derived from organic compounds not containing nitrogen or phosphorus and that its formation is much slower than that of sulfide. The solubility coefficient in seawater (salinity = 40‰) is …
Water Quality Study Of Lake Mead, Dale A. Hoffman, Paul R. Tramutt, Frank C. Heller, Bureau Of Reclamation
Water Quality Study Of Lake Mead, Dale A. Hoffman, Paul R. Tramutt, Frank C. Heller, Bureau Of Reclamation
Publications (WR)
This report presents Lake Mead Water quality data obtained from 1964 to 1966. The effect of filling Lake Powell on the water quality of Lake Mead is evaluated. General limnological principles and the present limnology of Lake Mead are discussed. Lake Mead has a warm monomictic annual temperature cycle characterized by summer stratification, fall overturn leading into a continuous circulation throughout the winter; temperatures never fall below 39 deg F (4 deg C). During stratification, lower dissolved oxygen values were recorded in the thermocline than in the epilimnion and hypolimnion. Mineral content increases from the upper to the lower end …
A Study Of The Synthesis And Reactions Of Condensed Pyriadazines, Lorraine Marie Distefano
A Study Of The Synthesis And Reactions Of Condensed Pyriadazines, Lorraine Marie Distefano
Chemistry and Chemical Biology ETDs
A special interest in a nitramine rearrangement prompted the preparation of 1,4-diaminopyridazino [4,5-d] pyridazine and the nitration of this compound. Several reactions of the intermediates, which were synthesized en route to 1,4-diaminopyridazino [4,5-d] pyridazine, were studied. Strong evidence for the existence of keto-enol tautomerism was found in the case of 1,4-dihydroxypyridazino [4,5-d] pyridazine and its derivatives.
Some reactions of 5, 8-dichloropyrazino [2,3-d] pyridazine were studied with particular interest in the nucleophilic displacement of azides and in the nitration of 5,8-dianilinopyrazino [2,3-d] pyridazine.
The nitration of diaminophthalazine was also attempted in order to perform an acid catalyzed nitramine rearrangement from one …
The Synthesis Of 3-Hydroxy-4-Imidazolidiones, Victor L. Rizzo
The Synthesis Of 3-Hydroxy-4-Imidazolidiones, Victor L. Rizzo
Masters Theses
No abstract provided.
An Investigation Of The Refractive Index Of Selected Liquids In The Ultraviolet, Robert Bruce Eaton
An Investigation Of The Refractive Index Of Selected Liquids In The Ultraviolet, Robert Bruce Eaton
Masters Theses
No abstract provided.
A Balanced Salt Culture Medium For Halteria Grandinella, Yee Wan Mark
A Balanced Salt Culture Medium For Halteria Grandinella, Yee Wan Mark
All-Inclusive List of Electronic Theses and Dissertations
The animals that the writer worked with liere the unicellular organisms called liaJ,tez:ia grandil.!iilJ.a• They belong to the Pl~lum Protozoa and are placed in the Class Ciliata and the Order Oligotrichia. llftltez'A gDJ}gini•U, like most protozoa, ll ve in waters but they seem to prefer qUiet pools, lakes, and ponds in which aqua i;;!c plants are growing and in which there is much organic matter.
The Monadnock Volume 41, June 1967, Clark University Geographical Society
The Monadnock Volume 41, June 1967, Clark University Geographical Society
The Monadnock (Clark Geographical Society)
Volume 41 of The Monadnock. The Monadnock was the alumni magazine of the Clark University Geographical Society (1927-1985) (2014-present).
A Study Of Chromium-Doped High Lead Containing Silicate Glasses For Possible Laser Action, Mervet Maurice Saleh
A Study Of Chromium-Doped High Lead Containing Silicate Glasses For Possible Laser Action, Mervet Maurice Saleh
Archived Theses and Dissertations
No abstract provided.
An Odontometric Study Of Five Contemporary Western United States Indian And Alaskan Eskimo Groups, John A. Matis
An Odontometric Study Of Five Contemporary Western United States Indian And Alaskan Eskimo Groups, John A. Matis
Loma Linda University Electronic Theses, Dissertations & Projects
The morphologic characteristics of the oral cavity in five contemporary Western Indian and Alaskan Eskimo groups have been investigated by the use of study models of the dental archs. The sample consisted of 216 individuals, including 44 Navajos, 43 Apaches, 40 Papagos, 42 Pimas and 47 Alaskan Eskimos.
The first purpose of the study was to determine the extent of investigator error. This was accomplished by remeasuring many morphologic traits of the dentition in 125 Indians which had previously been measured by different investigators using the same study models. It was found that investigator error can be significant, even in …
A Pre- And Post-Improvement Study On Six Southeast Kansas Strip-Mine Lakes, William Thomas Waller
A Pre- And Post-Improvement Study On Six Southeast Kansas Strip-Mine Lakes, William Thomas Waller
Electronic Theses & Dissertations
During the last sixty years extensive experimental research has been conducted in an attempt to establish methods of controlling the acid conditions resulting from coal mine operations.
It was the purpose of this research to determine the feasibility of reclaiming acid strip-mine lakes for use as potential fisheries management areas. To accomplish the objectives outlined above a two-phase program was initiated. The first phase involved the physical alteration of the drainage areas of the experimental lakes included in this study in an attempt to divert all visible signs of acid drainage to areas other than those incorporated into the drainage …
Epr Spectra Of Divalent Manganese In Halide Crystals, Veron Sarkis Sarkissian
Epr Spectra Of Divalent Manganese In Halide Crystals, Veron Sarkis Sarkissian
Archived Theses and Dissertations
No abstract provided.
Estimation Of Parameters Of Normal Populations From Truncated Samples, Kuo-Chung Liang
Estimation Of Parameters Of Normal Populations From Truncated Samples, Kuo-Chung Liang
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
In statistical experiments, if a random sample of items drawn from a population is tested until all items fail, conventional statistical techniques may be employed but normal frequency distributions may not be satisfied. Failure of the data to satisfy the assumption of normality may lead to an invalid result. Some statistical results, however, have been shown to be robust to the failure of the data to meet normality. When using conventional experimental methods, considerable time and money are required to produce failure of all samples. To be economical, many experiments are concluded before all test items fail. A sample obtained …
Movement Of Atrazine In Soil Under Furrow Irrigation, Jyothi Veerabhadrappa
Movement Of Atrazine In Soil Under Furrow Irrigation, Jyothi Veerabhadrappa
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Movement of atrazine in response to furrow irrigations was studied using the samples of Timpanogos silt loam soil. Distribution in soil profile of surface applied herbicide was determined by drawing samples of water extracts through porous cylinders. Atrazine quantity was determined by spectrophotometer.
It was observed that the herbicide found in the water extracts was an indication of the quantity present in the soil. The herbicide moved readily with the applied water. Irreversible thermodynamic model could not be applied because of the initial and final boundary conditions. The pattern of movement was in conformity with the chromatographic theory.
The Influence Of Thermo-Gradients Upon Water Movement And Retention In Unsaturated Soils, Jose V. Salazar
The Influence Of Thermo-Gradients Upon Water Movement And Retention In Unsaturated Soils, Jose V. Salazar
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Temperature differences of about 5, 10, and 15 V, were applied to uniformly packed and insulated horizontal column of Millville silt loam soil using mean temperatures near 13, 14, 15, 16, 17, 18, 19, 20 and 23.5 C. The temperature distribution along the soil column was determined using copper constantan thermocouples. Soil samples were taken to determine volumetric moisture content, and soil water potential, using the vapor pressure psychometer technique. The thermodynamic flow equation of Taylor and Cary, (1964) was used to calculate the hydro-thermal transfer coefficient (ß) as given by:
-ß = d(μw)T / dlnT
where …
The Interaction Between Water Movement, Solute Uptake, And Respirational Energy In Plant Roots, Mohamed Sadek Tawakol
The Interaction Between Water Movement, Solute Uptake, And Respirational Energy In Plant Roots, Mohamed Sadek Tawakol
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Sunflower plants (Helianthus annus, var. Russian mammoth) were grown in Hogland nutrient solution. The roots (after being subjected to treatments with either respiratory inhibitors or respiratory stimulators) were used to measure the flux of water Jw, flux of solute Js , and the rate of respiration Jo.
The thermodynamic theory of irreversible processes was used to examine the interaction between fluxes, and the changes in conductivity under different treatments. The rate equations for a root membrane of unit thickness were developed as:
Jw = LwwVw∆p + LwsRT ln …
An Exposition On Bayesian Inference, John Laffoon
An Exposition On Bayesian Inference, John Laffoon
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Bayesian approach to probability and statistics is described, a brief history of Bayesianism is related, differences between Bayesian and Frequentist schools of statistics are defined, protential applications are investigated, and a literature survey is presented in the form of a machine-sort card file.
Bayesian thought is increasing in favor among statisticians because of its ability to attack problems that are unassailable from the Frequentist approach. It should become more popular among practitioners because of the flexibility it allows experimenters and the ease with which prior knowledge can be combined with experimental data.