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Articles 1681 - 1710 of 2077
Full-Text Articles in Physical Sciences and Mathematics
Mössbauer Studies Of Impurity Tin Atoms In Indium, Richard L. Smith
Mössbauer Studies Of Impurity Tin Atoms In Indium, Richard L. Smith
Masters Theses
No abstract provided.
Positron Annihilation In Single Crystal Zinc At 250 Degrees Centigrade, Jon Wayne Swanson
Positron Annihilation In Single Crystal Zinc At 250 Degrees Centigrade, Jon Wayne Swanson
Masters Theses
No abstract provided.
Angular Correlation Study Of The 105 Kev Level In Gd155, John B. Gouvas
Angular Correlation Study Of The 105 Kev Level In Gd155, John B. Gouvas
Masters Theses
No abstract provided.
Kinetics Of The Thermal Decomposition Of Acetonitrile, Thomas William Asmus
Kinetics Of The Thermal Decomposition Of Acetonitrile, Thomas William Asmus
Masters Theses
No abstract provided.
Fluorescence Studies Of Cobalt (Iii) Complexes, Arnold T. Weibel
Fluorescence Studies Of Cobalt (Iii) Complexes, Arnold T. Weibel
Masters Theses
No abstract provided.
Surface Interactions Between Nickel Ions And Sodium Dodecyl Sulfate, Ralph Edward Coleman
Surface Interactions Between Nickel Ions And Sodium Dodecyl Sulfate, Ralph Edward Coleman
Masters Theses
"In this research the interaction of nickel ions with the surfactant sodium dodecyl sulfate at the liquid-air interface was studied. Surface tension measurements were performed on pure sodium dodecyl sulfate solutions, with and without the addition of nickel ions. Results of these measurements showed that the addition of nickel ions lowered the equilibrium surface tension values of pure sodium dodecyl sulfate solutions and shifted the critical micelle concentration to lower concentrations. The foam fractionation technique was used to determine if the nickel ions could be removed from surfactant solutions. It was found that the removal of nickel ions was influenced …
The Effect Of Impurities On The Time Dependence Of The Surface Tension Of Aqueous Surfactant Systems, Elizabeth Ann Munson
The Effect Of Impurities On The Time Dependence Of The Surface Tension Of Aqueous Surfactant Systems, Elizabeth Ann Munson
Masters Theses
"In this study surface tension measurements were made on tetradecylpyridinium bromide (TPB) solutions both in water in solutions containing various concentrations of impurities. Three impurities were studied, dodecyl alcohol, decyl alcohol and dodecylpyridinium bromide. Surface tension vs. time plots were constructed and show a definite dependence on the concentration of the impurity added. As the concentration of the impurity increases the equilibrium surface tension decreases. The decrease in the equilibrium surface tension is also dependent upon the concentration of the tetradecylpyridinium bromide. As the concentration of the surfactant (TPB) increases the effect of the impurity is reduced"--Abstract, page i.
A Study Of Solvent Effects On The Reaction Between P-Nitrobenzyl Chloride And Hydroxide Ion In Aqueous Dioxane Homogeneous Media, Ken K. Ho
Masters Theses
"The kinetics and activation parameters of the reaction between p̲, p̲' - dinitrostilbene quantitatively, have been studied in five aqueous dioxane solvent systems at five different temperatures between 20⁰ and 40⁰C. At any one temperature the second-order rate constants are minimum in the 30% dioxane solvent mixture, reach a maximum in the 50% dioxane systems, and fall off slightly in the 60% and 70% dioxane systems. The Arrhenius activation energies are highest in the 30% dioxane and lowest in the 70% dioxane systems. The free energies of activation change in the same direction but the magnitude of change is much …
Geochemical Abundance Of Iodine, Jane Hanisch Bennett
Geochemical Abundance Of Iodine, Jane Hanisch Bennett
Masters Theses
"The research reported herein includes unpublished iodine and uranium data on a group of United States Geological Survey standards and on a group of ultrabasic rocks. Data are also included for the major rock types, deep sea sediments, and for graphite and troilite inclusions in iron meteorites. Tellurium data for the troilite are also reported. Appendix I is a literature article (Bennett and Manuel, 1967a) on Canyon Diablo Graphite. Appendix II is a literature article (Bennett and Manuel, 1967b) on deep sea sediments. The results of this study show that most of the earlier estimates of the crustal abundance of …
A Kinetic Investigation Of The Reaction Of Ethylenedinitrilotetraacetic Acid (Edta) And Cerium (Iv) In Acid Solution, Sahmia K. Al-Hashimi
A Kinetic Investigation Of The Reaction Of Ethylenedinitrilotetraacetic Acid (Edta) And Cerium (Iv) In Acid Solution, Sahmia K. Al-Hashimi
Masters Theses
"The reaction between Ce(IV) salt solutions and EDTA solution was followed titrimetrically and spectrophotometrically and found to occur in stages. Four equivalents of Ce(IV) are reduced per mole of EDTA almost instantaneously at room temperature or even lower. With increasing temperature and reaction time an ultimate of about 14 equivalents of Ce(IV) is consumer per mole of EDTA. Formaldehyde, carbon dioxide, and other unidentified compounds are the products of oxidation of EDTA with Ce(IV). The kinetics of the reaction in aqueous sulfuric acid (0.09 - 2.95 M̲) was studied over the temperature range 11.7-40⁰ by a spectrophotometric technique. In the …
Sulfide Mineralogy And Fabrics Of The Iron Ores At Benson Mines, New York, Pedro Hugo TumialáN De La Cruz
Sulfide Mineralogy And Fabrics Of The Iron Ores At Benson Mines, New York, Pedro Hugo TumialáN De La Cruz
Masters Theses
"The occurrence of sulfide minerals and their textural relationships to the silicate and oxide minerals in the Benson Mines, New York, iron deposit were investigated by ore microscopic and petrographic means. The Benson deposit is one in which the dominant iron oxides, magnetite and hematite, occur in a quartz-feldspar gneiss which was subjected to hornblende granulite subfacies metamorphism. Two hundred ore and country rock specimens were systematically collected from all parts of the open pit mine. Polished sections and thin sections were prepared from nearly all of the collected specimens. The oxide ore exhibits a granular texture in which isolated …
The Geology Of The Thayer Area Emphasizing The Stratigraphy Of The Cotter And The Jefferson City Formations, William Jesse Hedden
The Geology Of The Thayer Area Emphasizing The Stratigraphy Of The Cotter And The Jefferson City Formations, William Jesse Hedden
Masters Theses
"Detailed geologic mapping of the Cotter-Jefferson City formational contact in the Thayer, Missouri area demonstrates the feasibility of using this contact. This mapping also delineates significant faulting in the area.
The stratigraphy of the Cotter and Jefferson City formations in the Thayer area has been studied to find a mappable contact between the two formations. The contact was mapped in this area by using marker beds, the stratigraphic positions of which were determined by applying insoluble residue techniques to outcrop sections. Because the insoluble residue zones of the Cotter and Jefferson City formations are recognizable throughout the state of Missouri …
The Downhole Suspension And Testing Of An Electrodynamic Shear Wave Exciter, Robert Franklin Kehrman
The Downhole Suspension And Testing Of An Electrodynamic Shear Wave Exciter, Robert Franklin Kehrman
Masters Theses
"The work in this research project was aimed at designing a Downhole Electromagnetic Shear Wave Generator capable of delivering a wide frequency band, random, continuous signal. This Exciter was built using a compressed-air driven piston assembly for downhole application. The device was tested in the laboratory in a concrete test facility. It proved to be capable of transmitting a continuous, measurable stress into the concrete in a 100 to 5,000 hertz frequency band"--Abstract, page ii.
Absolute Specification Of X-Ray Spectra By Laplace Transform Analysis Of Attenuation Data, Gerald Robert Lusk
Absolute Specification Of X-Ray Spectra By Laplace Transform Analysis Of Attenuation Data, Gerald Robert Lusk
Masters Theses
"A well characterized, variable plate separation ion chamber was utilized as a detector to collect x-ray attenuation data for generating information on the Laplace transform predicted spectrum of a 50 KvCP conventional x-ray tube. The variable plate separation feature allows one to include a wavelength dependent correction to the detector response which is associated with the hardening of the x-ray spectrum as it traverses the attenuating material. With this correction, the conventional two-term Laplace transform was shown to approximate independently the bremsstrahlung and characteristic L radiation from the tungsten target. The detector provides an absolute statement of the target-referenced x-ray …
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.
A Comparison Of Three Numerical Techniques Used For The Solution Of The Two-Point Boundary Value Problem, William Richard Krall
A Comparison Of Three Numerical Techniques Used For The Solution Of The Two-Point Boundary Value Problem, William Richard Krall
Masters Theses
"Three numerical approximation techniques, called the Initial step, Shooting, and Direct Finite Difference Techniques, respectively, are compared and discussed as they apply to the solution of both linear and non-linear boundary-value problems of the form y"=f(x,y,y') with endpoint conditions y(xo)=yo and y(xn)=yn. The techniques are compared with respect to speed and accuracy by comparing the solution of each problem considered four times, each time for a different increment value, and comparing the errors at four pivotal points chosen at equally spaced distances over the domain of the function, to give an indication of …
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 …
A Study Of Bismuth Ferrate And Bismuth Manganate In Solid Solution With Lead Titanate, Harris C. Jones
A Study Of Bismuth Ferrate And Bismuth Manganate In Solid Solution With Lead Titanate, Harris C. Jones
Masters Theses
"A new sample holder for measuring the high frequency dielectric constant of ferroelectrics at high temperature was constructed. The new sample holder eliminated discontinuities in the slotted line and improved the electrical contact between the ceramic and brass components. Measurements of the high frequency dielectric constant of an aged sample of 90% BiFeO₃ - 10% PbTiO₃ were made as a function of temperature using the slotted line technique. The dissipation function for the aged sample was found to have a more normal behavior near the Curie point than the virgin samples previously measured. Resistivity measurements were made as a function …
Electronic Transitions In Diatomic Molecules, James O. Hornkohl
Electronic Transitions In Diatomic Molecules, James O. Hornkohl
Masters Theses
"The electronic transition moments of many band systems have been found to be linear functions of the internuclear distance. However, some band systems exhibit a quadratic variation of the transition moment. In these quadratic cases, the plots from which the variation of the transition moment is determined are based upon the approximation of the second r-centroid by the square of the first r-centroid. The square of the first r-centroid does closely approximate the second r-centroid by a simple error analysis shows that the small difference between the two is not a quantitative measure of the error introduced into the transition …
Design And Testing Of A Downhole Continuous Wave Generator, Cole L. Smith
Design And Testing Of A Downhole Continuous Wave Generator, Cole L. Smith
Masters Theses
"The continuous shear wave generator was designed to be the first instrument capable of producing a continuous high frequency signal below the weathered layer of the earth. This is to be accomplished by placing the instrument in a bore hole and lowering it below the weathered layer where the higher frequencies are severely attenuated. The generator produced a measurable signal output with the output force being approximately 11 pounds force. Testing of the generator showed the necessity of using a spring system with a low natural frequency. The testing also indicated several improvements which should be made in the generator …
A Development Of Regression Models For Predicting Temperature, Salinity And Sound Velocity In Sea Water, Darwin Wayne Brown
A Development Of Regression Models For Predicting Temperature, Salinity And Sound Velocity In Sea Water, Darwin Wayne Brown
Masters Theses
"There are in existence today some reasonably good numerical procedures for predicting sound velocity, but these procedures require that certain initial data such as temperature and salinity be given before a sound velocity may be computed. Eliminating the need for on-location observations of temperature and salinity, which are used in computing sound velocity, was the primary objective of this study. Stepwise multiple regression was applied in the search for suitable models to predict temperature and salinity, and ultimately sound entirely in terms of controllable variables, such as latitude, longitude, depth, and day-of-year"--Abstract, page ii.
Magnetic After-Effects In Dilute Transition Metal Alloys, Robert Henry Graham
Magnetic After-Effects In Dilute Transition Metal Alloys, Robert Henry Graham
Masters Theses
"Temperature dependent after-effects of the initial permeability in ternary dilute ferromagnetic iron-base alloys were studied in the temperature range of -50°C to +30°C. Interstitial carbon and nitrogen were the diffusing elements. Nominal percentages of the substitutional transition elements manganese, chromium, vanadium and titanium were added to determine the extent of substitutional-interstitial pair interactions. No additional temperature dependent after-effect of the initial permeability was noticed in Fe- substitutional -C alloys, while such after-effects were present in Fe- substitutional -N alloys. Magnetic after-effect data were analyzed on the basis of single Debye relaxations. Relaxation times for carbon and nitrogen diffusion in alpha-iron …
Mineralization Of The Boss Bixby Anomaly, Iron And Dent Counties, Missouri, Frederick Joseph Smith
Mineralization Of The Boss Bixby Anomaly, Iron And Dent Counties, Missouri, Frederick Joseph Smith
Masters Theses
"The Boss-Bixby deposit is located on the line dividing Iron and Dent Counties and belongs to the Southeast Missouri Precambrian Iron Metallogenic Province. The sequence of events leading to the formation of the deposit is reviewed. The mineralization occurred after intrusion of intermediate magma, but prior to the intrusion of granite. The ore minerals present are the following in the order of deposition: magnetite, ilmenite, giekielite, hematite, rutile, pyrite, molybdenite, cobaltite, chalcopyrite, bornite, sphalerite, galena, limonite, chalcocite, and cuprite. Four different methods of zoning are presented. Partial pressures of oxygen and sulphur [sic], as well as temperature controlled sequential deposition …
Infrared Related Solid State Studies, Donald George Rathbun
Infrared Related Solid State Studies, Donald George Rathbun
Masters Theses
"Infrared reflectivity measurements have been made on single crystal CdS. Classical dispersion analysis has been used in an analysis of the data to obtain the index of refraction, the extinction index, and the dispersion parameters. These are compared with previously published results. The procedure used in this analysis has been outlined for future reference. Also, the shallow donor impurity theory has been used to numerically calculate the d±1 levels for Si and Ge. The theory is extended for the case of the impurity in the bulk semiconductor and the d₀, d±2 and, for high n, the s, p₀, …
A Study Of Bifeo₃ And The Hall Effect In Bifeo₃ And Cds, Fred Hoerger Taylor
A Study Of Bifeo₃ And The Hall Effect In Bifeo₃ And Cds, Fred Hoerger Taylor
Masters Theses
"Pure samples of BiFeO₃ were heat treated in oxygen and nitrogen atmospheres in an attempt to reduce the conductivity of the samples. Dielectric constant and dissipation factor measurements, as a function of frequency, were made to determine whether the samples had been altered. A special high temperature Hall effect apparatus was constructed. Using this apparatus an upper limit for the Hall mobility in BiFeO₃ was established. The apparatus was also used for room temperature measurements of Ga-doped CdS samples. Resistivity measurements to be used with the Hall effect results were made on both the BiFeO₃ and the CdS samples. Hot-Point …
Lateral Variations Of Carbonate Rock Adjacent To Ore Deposits In The Upper Mississippi Valley Zinc-Lead District, Wisconsin, Illinois, Iowa, Mehdi H. Mirbaba
Lateral Variations Of Carbonate Rock Adjacent To Ore Deposits In The Upper Mississippi Valley Zinc-Lead District, Wisconsin, Illinois, Iowa, Mehdi H. Mirbaba
Masters Theses
"The lateral variation and nature of carbonate host rock in the Upper Mississippi Valley zinc-lead district were petrographically studied within the McGregor and Quimbys Mill Members of the Platteville Formation of the Middle Ordovician System. These members are dolomitic limestone in the Upper Mississippi Valley district of southwestern Wisconsin, northwestern Illinois and northeastern Iowa. One hundred and twenty-seven specimens were collected or were available from pull drifts in the Shullsburg mine. The specimens were collected at regular intervals of 50 or lOO feet in seven pull drifts between eight ore bodies. Thin sections prepared from the carbonate specimens were studied, …
An Indirect Spectrophotometric Method For Expansion Of The Optimum Concentration Range, Henry David Mitchell
An Indirect Spectrophotometric Method For Expansion Of The Optimum Concentration Range, Henry David Mitchell
Masters Theses
No abstract provided.
The Evaluation Of Certain Serum Iron Analyses By Atomic Absorption Spectroscopy, James Allan Boersma
The Evaluation Of Certain Serum Iron Analyses By Atomic Absorption Spectroscopy, James Allan Boersma
Masters Theses
No abstract provided.
Pyrolysis Kinetics Of Ethyl Nitrate, Betty Meihorng Lee
Pyrolysis Kinetics Of Ethyl Nitrate, Betty Meihorng Lee
Masters Theses
No abstract provided.
Measurement Of Ultrasonic Absorption In Liquids By A Thermal Method, Ronald J. Tanis
Measurement Of Ultrasonic Absorption In Liquids By A Thermal Method, Ronald J. Tanis
Masters Theses
No abstract provided.