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Articles 2191 - 2220 of 2634
Full-Text Articles in Physical Sciences and Mathematics
Vertical And Lateral Variations In A Welded Tuff, Ted Richard Dinkel
Vertical And Lateral Variations In A Welded Tuff, Ted Richard Dinkel
Masters Theses
"During the Tertiary period, nuée ardente type eruptions spread large deposits of welded tuffs over southwestern Utah and southeastern Nevada. The Wah Wah Springs Tuff is a member of one of the most extensive of these units, the Needles Range Formation of Oligocene age. Its known outcrop area is estimated at 13,000 square miles. Relief was slight in the area during the time of eruption to enable the flows to spread over so large an area. In an effort to analyze the lateral and vertical continuity of the member, a petrographic study was undertaken. The average composition of the Wah …
The Background Concentrations Of Copper, Lead, And Zinc In Streams Of The "New Lead Belt", Missouri, Nicholas Howard Tibbs
The Background Concentrations Of Copper, Lead, And Zinc In Streams Of The "New Lead Belt", Missouri, Nicholas Howard Tibbs
Masters Theses
"This study was initiated to determine the background concentrations of copper, lead, and zinc in the streams of the Viburnum Trend or New Lead Belt of southeast Missouri. Analytical methods were developed for atomic adsorption spectroscopy. These methods initially consisted of coextraction of cooper, lead, and zinc using the APDC/MIBK system, and finally of extraction of copper by APDC/MIBK and direct analysis of lead and zinc using the newly developed "Sampling Boat" technique. The data obtained from these analyses were arranged in histograms and critically analyzed. The background concentrations were established to be 4-6 ppb for all three elements. Methods …
A Low Frequency Phase Shift Method, Ronnie Carroll Mcmillan
A Low Frequency Phase Shift Method, Ronnie Carroll Mcmillan
Masters Theses
"The phase shift method of measuring atomic lifetimes is particularly useful because it allows us to make measurements in the steady state mode instead of in the transient mode. High frequency phase shift techniques cause many problems. The equipment, which was designed and built to make low frequency phase shift techniques possible, is shown schematically and discussed. The new experimental techniques employed in our apparatus are a phase multiplier and a unique method of using a photomultiplier as a mixer. In the photomultiplier the final dynode is used as the grid of a triode. The next to the last dynode …
A Study Of The Evaporation Rates Of Small Freely Falling Water Droplets, Hugh Alan Duguid
A Study Of The Evaporation Rates Of Small Freely Falling Water Droplets, Hugh Alan Duguid
Masters Theses
"The evaporation rates of small (radium 3-9µ), freely falling water droplets were determined. the droplets, produced in a diffusion cloud chamber, were allowed to fall through air of known relative humidity (95-100%) and at three ambient temperatures (25C, 30C, and 35C) in a vertical drift tube. the rates of evaporation were ascertained by recording the drop positions on film at fixed time intervals. The results are compared with several existing theories, and are found to lie between the formulation of Kinzer and Gunn, and the quasistationary theory based on Maxwell's equation"--Abstract, page ii.
An X-Ray Diffraction Study By The Powder Method Of Solid Solutions In The System Zno-Cro3-H2O At 25° C, William Alan Livingston
An X-Ray Diffraction Study By The Powder Method Of Solid Solutions In The System Zno-Cro3-H2O At 25° C, William Alan Livingston
Masters Theses
No abstract provided.
The Construction Of A Portable Hologram Camera, Michael Bruce Elzinga
The Construction Of A Portable Hologram Camera, Michael Bruce Elzinga
Masters Theses
No abstract provided.
Spectrophotometric Studies Of Complex Formation Of Alpha Aminohydroxamic Acids, Jing Shyong Chen
Spectrophotometric Studies Of Complex Formation Of Alpha Aminohydroxamic Acids, Jing Shyong Chen
Masters Theses
No abstract provided.
An Analysis Of General Patterns And Variations In The Occurrence Of Wet And Dry Days In Benton Harbor, Michigan, Linda Rae Dalrymple
An Analysis Of General Patterns And Variations In The Occurrence Of Wet And Dry Days In Benton Harbor, Michigan, Linda Rae Dalrymple
Masters Theses
No abstract provided.
A Study Of The 16.7 Mev Level Of The 5He, James David George
A Study Of The 16.7 Mev Level Of The 5He, James David George
Masters Theses
No abstract provided.
A Category Of Banach Spaces, Kenneth Leroy Pothoven
A Category Of Banach Spaces, Kenneth Leroy Pothoven
Masters Theses
No abstract provided.
A Study Of A Graphical Valued Function Associated With An Extension Of Graphs, Douglas W. Nance
A Study Of A Graphical Valued Function Associated With An Extension Of Graphs, Douglas W. Nance
Masters Theses
No abstract provided.
Numerical Evaluations Of The Virial Integrals, Li-Hwa Lee
Numerical Evaluations Of The Virial Integrals, Li-Hwa Lee
Masters Theses
No abstract provided.
Extensions Of The Sigma And Tau Functions, Meredith Woods Potter
Extensions Of The Sigma And Tau Functions, Meredith Woods Potter
Masters Theses
No abstract provided.
Mössabauer Studies Of Impurity Tin Atoms In Indium, Richard L. Smith
Mössabauer Studies Of Impurity Tin Atoms In Indium, Richard L. Smith
Masters Theses
No abstract provided.
Cerebrosides Of Human Aorta: Isolation And Fatty Acid Distribution, Eric Coles
Cerebrosides Of Human Aorta: Isolation And Fatty Acid Distribution, Eric Coles
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.
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.
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.
Fluorescence Studies Of Cobalt (Iii) Complexes, Arnold T. Weibel
Fluorescence Studies Of Cobalt (Iii) Complexes, Arnold T. Weibel
Masters Theses
No abstract provided.
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 …
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.
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 …
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 …
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.
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.
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 …
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 …
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, …
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 …