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Doctoral Dissertations

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Cell Model Of A Fluid With Hard-Core Repulsive Long-Range Attractive Potential, Ralph G. Tross Jan 1968

Cell Model Of A Fluid With Hard-Core Repulsive Long-Range Attractive Potential, Ralph G. Tross

Doctoral Dissertations

"A model of a one-dimensional fluid is investigated in which the praticles [sic] are embedded in a cellular space grid and interact with a modified Lennart-Jones potential. It is shown that with an appropriate change in the potential function the model is also suitable for a two- or three-dimensional fluid with more restricted interactions. The man-fermion-like nature of the system resulting from the hard-rod repulsive part of the modified Lennard-Jones potential makes possible an isomorphism between occupation numbers (number operators) and spin states (spin operators) of an Ising ferromagnet, permitting a convenient mathematical formulation of the problem in terms of …


A Numerical Simulation Of Pressure Distribution And Radius Of Drainage In Infinite Radial Aquifers - Constant Rate Case, Alton John Nute Jan 1968

A Numerical Simulation Of Pressure Distribution And Radius Of Drainage In Infinite Radial Aquifers - Constant Rate Case, Alton John Nute

Doctoral Dissertations

"The diffusivity equation for the transient flow of slightly-compressible liquids has been solved for infinite radial aquifers, subject to constant terminal rates, by employing a Romberg integration of the Van Everdingen - Hurst explicitly solution over the transformed integral limits for .01̲TD>500, the classical solutions presented by Carslaw and Jaeger, Mortada, Theis, and others are incorporated in the digital analysis to yield dimensionless pressures for 40 selected dimensionless radius (RD) ratios between 1 and 64 for dimensionless time values of .0005 to 1000.0. A new expression for dimensionless pressure-distribution, PD'(RD, TD), as a fraction of well bore pressure drop …


Deuterium Isotope Effects On The Solvolysis Rates Of Cyclopentyl Brosylates And Tosylates, Jimmie D. Christen Jan 1968

Deuterium Isotope Effects On The Solvolysis Rates Of Cyclopentyl Brosylates And Tosylates, Jimmie D. Christen

Doctoral Dissertations

"The brosylates and tosylates of cyclopentanol and its 1-d₁, c̲i̲s̲-2-d₁, t̲r̲a̲n̲s̲-2-d₁, and 2,2,5,5-d₄ analogs have been synthesized and their solvolysis rates measured at 25° in 70% vol. ethanol-water. The solvoylsis reactions were monitored by a conductance method. The isotope effects, kH/kD, observed for the brosylates and tosylates of each of the isotopically substituted cyclopentyl alcohols are as follows: 1-d₁-brosylate (1.1869) and 1-3₁-tosylate (1l1836); c̲i̲s̲-2-d₁-brosylate (1.1533) and c̲i̲s̲-2-3₁-tosylate (1.1577); t̲r̲a̲n̲s̲-2-d₁-brosylate (1.1803) and t̲r̲a̲n̲s̲-2-d₁-tosylate (1.1765); 2,2,5,5-d₄-brosylate (1.8881) and 2,2,5,5-d₄-tosylate (1.8863). The closeness in magnitude of the isotope effects for the c̲i̲s̲- and t̲r̲a̲n̲s̲-isomers is important in that it …


Inferences On The Parameters Of The Weibull Distribution, Darrel Ray Thoman Jan 1968

Inferences On The Parameters Of The Weibull Distribution, Darrel Ray Thoman

Doctoral Dissertations

"For the most part, solutions to the problems of making inferences about the parameters in the Weibull distribution have been limited to providing simple estimators of the parameters. Little has been known about the properties of the estimators. In this paper the small and moderate sample size properties of the maximum likelihood estimators are studied and their superiority is established. The problem of making further inferences which are based on the maximum likelihood estimates of the parameters is then considered. The inferences that are presented can be divided into those based on a single sample and those based on two …


Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe Jan 1968

Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe

Doctoral Dissertations

"The circulating drop mass transport model based on Hadamard's dispersed phase stream function was solved numerically to account for a solute diffusing into a droplet and undergoing a first order irreversible reaction with the drop medium for the case where the continuous phase resistance to solute transport is negligible ... Experimental data were obtained for a system which consisted of 2-chloro-2-methylpropane (t-butyl chloride) diffusing from a benzene continuous phase into falling water droplets and undergoing a first order irreversible reaction with the water droplets ... The experimental solute transport rates were a factor of 7 to 10 greater than those …


The Identification And Evaluation Of Toxic Effects Of Organic Micropollutants, John Warren Smith Jan 1968

The Identification And Evaluation Of Toxic Effects Of Organic Micropollutants, John Warren Smith

Doctoral Dissertations

No abstract provided.


On The Asymptotic Behavior Of Solutions Of An Nth Order Nonlinear Differential Equation, Philip Mosiman Locke Jan 1967

On The Asymptotic Behavior Of Solutions Of An Nth Order Nonlinear Differential Equation, Philip Mosiman Locke

Doctoral Dissertations

No abstract provided.


Some Types Of Unique Factorization In Integral Domains, Raymond A. Beauregard Jan 1967

Some Types Of Unique Factorization In Integral Domains, Raymond A. Beauregard

Doctoral Dissertations

No abstract provided.


A Calorimetric Study Of The Effects Of Surface Energy In A Type Ii Superconductor, Robert Rex Rice Jan 1967

A Calorimetric Study Of The Effects Of Surface Energy In A Type Ii Superconductor, Robert Rex Rice

Doctoral Dissertations

"A calorimetric study of the effects of the interphase surface free energy has been conducted on ellipsoidal samples of first and second kind superconductors. The measurements were performed using a specially designed magnetization calorimeter by two different techniques. The measurements were made on lead, tin, lead-4at%thallium, and tin-6at% indium. The results confirm the existence and experted sign of the surface energy in a well annealed lead-4at%thallium sample, and indicate that the interphase surface energy in lead and tin is too small to be directly detected by this method. The measured latent heats of transition of lead and tin agree well …


Centrifugal Model Study And Finite Element Analysis Of Stress Near A Fault, Christopher Haycocks Jan 1967

Centrifugal Model Study And Finite Element Analysis Of Stress Near A Fault, Christopher Haycocks

Doctoral Dissertations

"The adverse effects of faults on the stability of underground openings has long been realized. To date, however, discontinuities and most other types of geologic heterogeneities have not been amenable to mathematical analysis using the classical theories of elasticity and plasticity. This investigation examines the stress distribution around a single discontinuity and compares the experimental and numerical methods used for the analysis. The theory of elasticity, employing the equations of compatibility, equilibrium etc., was used to determine a stress function for the stress distribution around a circular hole loaded in a centrifugal field. The analysis was terminated after the stress …


The Transient Dynamics Of Plane Mechanisms, Navnit Chhaganlal Mehta Jan 1967

The Transient Dynamics Of Plane Mechanisms, Navnit Chhaganlal Mehta

Doctoral Dissertations

"Accurate determination of dynamic characteristics of mechanisms has become more important with increased requirements on speed, efficiency and precision. Many devices, such as circuit breakers and computing mechanisms, operate under purely transient conditions and actuation time places a serious limitation on the response of the system of which these devices are a part.

In the classical analysis, whether it be graphical or analytical, the mechanism is assigned a specified position and state of motion from which the forces required to produce the motion can be determined. The inverse problem of specifying the driving force and determining the resulting motion, which …


A Theoretical Investigation Of Elastic And Voigt Transient Spherical Waves, And Plane Three-Element Viscoelastic Waves, Edward Hornsey Jan 1967

A Theoretical Investigation Of Elastic And Voigt Transient Spherical Waves, And Plane Three-Element Viscoelastic Waves, Edward Hornsey

Doctoral Dissertations

"A mathematical model of explosive generated waves in rock is needed in many areas of engineering endeavor. Investigations to date have been unsuccessful in obtaining a model that satisfactorily represents real wave phenomena at all radial distances and in all of the important characteristics.

In this investigation, spherical waves in elastic and Voigt media were investigated. Series solutions for plane waves in a three-element viscoelastic medium were obtained. A dual exponential pressure pulse, P(t) = Po (e-αt-e-ßt) was assumed because it can exhibit significant features of real pressure pulses while avoiding instantaneous rise time, which …


Kilocycle Range Dislocation Damping In Dilute Magnesium Alloy Single Crystals, Robert Ray Nothdurft Jan 1967

Kilocycle Range Dislocation Damping In Dilute Magnesium Alloy Single Crystals, Robert Ray Nothdurft

Doctoral Dissertations

"The kilocycle range dislocation damping and Young's modulus of single crystals of magnesium and single crystals of magnesium containing small additions of lithium, zinc, or aluminum have been studied as a function of strain amplitude, temperature, and time during annealing and following a high strain amplitude vibration. The data are compared to the Granato-Lücke theory of dislocation damping, the Granato-Hikata-Lücke theory for the recovery of damping following plastic deformation, and the Yamafuji-Bauer theory for the recovery of damping following a high strain amplitude vibration. Reasonable qualitative agreement is obtained between the Granato-Lücke theory and the observed dependence of the damping …


Matrix Computer Analysis Of Curvilinear Grid Systems, David Leon Fenton Jan 1967

Matrix Computer Analysis Of Curvilinear Grid Systems, David Leon Fenton

Doctoral Dissertations

"A general equilibrium-stiffness method of matrix structural analysis was adapted and applied to the solution of the member end forces and moments of each of the members in a curvilinear structural grid system. A structural system of this nature is commonly used as the supporting framework for a "steel-framed dome", in addition to being a basic structural component in many aerospace applications. An integral part of the development of the analysis was the development of a computer program to perform the many complex operations required to obtain the solution. The engineer, by supplying the appropriate structural data and load data …


Study Of Resonance Effects In Allenic And Related Systems, Robert Andrew Steinkamp Jan 1967

Study Of Resonance Effects In Allenic And Related Systems, Robert Andrew Steinkamp

Doctoral Dissertations

"In order to investigate the possibility of resonance effects through a non-coplanar substituted acetylene, synthesis of bis-(2,5,8-trimethyl-l-naphthyl)-acetylene was attempted. Condensation of acetylene with 2,5,8-trimethyl-l-tetralone to yield an acetylenic glycol followed by dehydration and dehydrogenation was expected to yield the desired non-coplanar acetylene. Comparison of its ultraviolet spectrum with that of di-l-naphthyl-acetylene would have suggested the true nature of the acetylene pi cloud. The acetylene condensation was unsuccessful, however.

Substituted allenes, which contain one sp hybridized carbon atom, were then successfully synthesized for a similar analysis of potential resonance effects. A series of para-substituted 4-phenyl-2-methylbutadienoic acids were synthesized and their pKa's …


An Investigation Of The Creep Characteristics Of Portland Cement Mortar Under Static And Dynamic Strain, Ikram-Ul-Haq Dar Jan 1967

An Investigation Of The Creep Characteristics Of Portland Cement Mortar Under Static And Dynamic Strain, Ikram-Ul-Haq Dar

Doctoral Dissertations

"The combined effect of static and dynamic loads on design of underground openings is currently receiving much attention. It is known that the time-dependent behavior of rock is considerably different when a dynamic load is superimposed on prestressed rock. The shape of an underground opening has a definite influence on the magnitude of the local stresses and these may be significantly larger than those due to the weight of the overlying rock alone. Under these conditions, even a small dynamic load in the form of vibrations caused by blasting, drilling and related operations may increase the stress beyond a critical …


Numerical Approximation To Performance Predictions Of Gas-Drive Reservoir With Or Without Gas-Cap And Gas Injection, Jagannath Rao Ghole Jan 1967

Numerical Approximation To Performance Predictions Of Gas-Drive Reservoir With Or Without Gas-Cap And Gas Injection, Jagannath Rao Ghole

Doctoral Dissertations

"The pressure-saturation transient history for a hydrocarbon reservoir is solved for solution-gas, gas-cap and injected-gas drives assuming the saturation-pressure variations depicted by Muskat, under specific restrictive assumptions. A prototype reservoir system and its transient pressure saturation distribution under production is systemized on an IBM 360-Model 40 Computer which allows the definition of the transient behavior of saturation with pressure declination and fluid withdrawal for preassigned initial saturations of the oil, water and gas phases. This analysis is then modified for the existence of a gas-cap and for the re-injection of produced gas volumes for pressure maintenance considerations and the ensuing …


Magnetic Properties Of The Bifeo₃-Pbtio₃-Pbzro₃ Ternary System, James Ivan Latham Jan 1967

Magnetic Properties Of The Bifeo₃-Pbtio₃-Pbzro₃ Ternary System, James Ivan Latham

Doctoral Dissertations

"The magnetic susceptibility and spontaneous magnetic moment of the perovskitic, polycrystalline solid solutions of BiFeO3 with PbTiO3, PbZrO3, and [50PbZrO3·50PbTiO3] were determined using the Faraday method. Pure BiFeO3 has a G-type antiferromagnetic structure. Although the perovskite BiFeO3 exhibits a sharp peak in the susceptibility at the Néel temperature, it does not possess a spontaneous magnetic moment. The solid solutions investigated possessed a spontaneous magnetic moment throughout the multiple cell rhombohedral region of the BiFeO3-PbTiO3-PbZrO3 ternary phase diagram, which extends from pure BiFeO3 to …


High Frequency Ferroelectric Properties Of The Bifeo₃-Pbtio₃-Pbzro₃ Ternary System, Robert Travis Smith Jan 1967

High Frequency Ferroelectric Properties Of The Bifeo₃-Pbtio₃-Pbzro₃ Ternary System, Robert Travis Smith

Doctoral Dissertations

"High temperature dielectric measurements have been performed on the ferroelectric and antiferroelectric perovskitic polycrystalline solid solutions in the BiFeO3-PbTiO3-PbZrO3 ternary system. The data were taken in the UHF frequency range with the use of a slotted line and specially constructed sample holder capable of operation at temperatures in excess of 800°C.

The Curie points have been found to occur at progressively higher temperatures with the increase of BiFeO3 content in the solutions except in phase transition regions where minima can occur. The dielectric constants at the Curie temperatures have been found to decrease with …


The Technique Of Lineaments And Linears Analysis And Its Application In The Minerogenic Province Of Southeast Missouri, Hassan A. Etr Jan 1967

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 …


Violation Of The Second And Third Adiabatic Invariants By Hydromagnetic Waves, Barney Jay Conrath Jan 1966

Violation Of The Second And Third Adiabatic Invariants By Hydromagnetic Waves, Barney Jay Conrath

Doctoral Dissertations

No abstract provided.


An Investigation Of The Control Of Hydraulic Fracturing Through The Inclusions Of Prefractures, William Joseph Kabeiseman Jan 1966

An Investigation Of The Control Of Hydraulic Fracturing Through The Inclusions Of Prefractures, William Joseph Kabeiseman

Doctoral Dissertations

"Among the methods for determining the in-situ state of stress within the earth’s crust, hydraulic fracturing has been and is receiving much attention. This method, in principle, measures stress directly with no delicate electronic equipment required nor knowledge of the elastic modulus of the material.

This dissertation investigates experimentally whether or not control of fracture orientation can be achieved by the introduction of circular and elliptical prefractures along with sand inclusions into cast hydrostone blocks which are hydraulically fractured. A mathematical model is presented and analytically solved for the stress condition associated with a circular crack containing fluid pressure with …


Calculated Cohesive Energy Of The Ordered Copper-Gold Alloy Cu Au I, Richard W. Hannum Jan 1966

Calculated Cohesive Energy Of The Ordered Copper-Gold Alloy Cu Au I, Richard W. Hannum

Doctoral Dissertations

"The ordered alloy CuAu is the fifty atomic per cent alloy in the copper-gold system. It was observed by Johansson and Linde(1) and was one of the first ordered alloys to be studied by x-ray diffraction methods(Z, 3). Two ordered superlattices of CuAu are observed. CuAu I exists below 380° C and has a tetragonal structure which is a slight distortion of the face- centered cubic. It is very highly ordered, with all copper and all gold atoms in alternate (002) planes, as shown in Figure 2. CuAu II, which exists between 380° and 415° C, is orthorhombic in structure(4) …


Geochemical And Petrological Study Of The Precambrian Iron Metallogenic Province Of Southeast Missouri, Geza Kisvarsanyi Jan 1966

Geochemical And Petrological Study Of The Precambrian Iron Metallogenic Province Of Southeast Missouri, Geza Kisvarsanyi

Doctoral Dissertations

"The general purpose of this dissertation was to investigate and establish petrological and geochemical relationships, if any, between the Precambrian iron deposits and associated host rocks. A more specific objective was to determine the distribution of some significant minor elements in the rocks and mineral deposits and to include specific mineralogical and petrological studies of the iron deposits and country rocks important to a better understanding of the genetic and geochemical relationships ... A primary task in the investigation was the study of the trace element population of individual iron deposits and establishment of differences, if they exist, between the …


The Anodic Dissolution Of Cadmium In Aqueous Solutions, San-Cheng Lai Jan 1966

The Anodic Dissolution Of Cadmium In Aqueous Solutions, San-Cheng Lai

Doctoral Dissertations

"The purpose of this investigation was to study the effect of cadmium ions on the anodic dissolution of cadmium in salt solutions of ·constant ionic strength. The concentration of the cadmium ions was varied from 0.001 to 1 N and the current density ranged from 0.001 to 0.1 amp•cm-2. The temperature was controlled at 25°C.

....A mathematical model was postulated expressing the anodic dissolution rate as the sum of electrochemical, local corrosion, and disintegration rates."--Abstract, page iii.


Cenozoic And Recent Lunulitiform Bryozoans Of The Gulf And Atlantic Coasts, Ronald Greeley Jan 1966

Cenozoic And Recent Lunulitiform Bryozoans Of The Gulf And Atlantic Coasts, Ronald Greeley

Doctoral Dissertations

"Free, cup-shaped colonies of cheilostomatous bryozoans, equipped with vibracula, are termed lunulitiform bryozoans. This group is found in sandy and calcareous Cenozoic deposits of the Gulf and Atlantic Coastal Plains. Cupuliform bryozoans are taxonomically distinct from, but in many ways similar to, lunulitiform bryozoans; the two groups are frequently found together.

Known lunulitiform genera of the Gulf and Atlantic Coastal Plains are diagnosed and their species described: Lunulites Lamarck, fifteen species, one new; Oligotresium Gabb and Horn, six species, two new; Discoporella d'Orbigny, two species; Cupuladria Canu and Bassler, two species; Selenaria Busk, one species; Otionella Canu and Bassler, four …


Theory Of The Lunar Photoelectron Atmosphere, Hal Emerson Mccloud Jr. Jan 1966

Theory Of The Lunar Photoelectron Atmosphere, Hal Emerson Mccloud Jr.

Doctoral Dissertations

"By considering the mechanics of an electron projected into an arbitrary potential field together with Poisson's equation it is possible to set up a differential equation for the electrostatic potential. The equation may be integrated and the photoelectron density found as a function of height for four approximate models. A simple model based upon monoenergetic photons and monoenergetic electrons ejected vertically upward yields rough estimates of the parameters of interest. Another model takes into account the fact that the photoelectrons are ejected at all angles. A general model takes into account the illumination of the lunar surface by solar (black …


Some Geological And Magnetic Characteristics Of Buried And Resurrected Precambrian Hills Of Southeastern Missouri, James Edward Palmer Jan 1966

Some Geological And Magnetic Characteristics Of Buried And Resurrected Precambrian Hills Of Southeastern Missouri, James Edward Palmer

Doctoral Dissertations

"PURPOSE AND SCOPE OF INVESTIGATION The major purpose of this investigation was to determine by a comprehensive study various geological and magnetic characteristics of buried and resurrected Precambrian hills of the Central Ozarks. A second important objective was the determination of characteristics which might aid in the location of buried Precambrian hills. A final objective was the testing of the magnetic surface integration method for identification and determination of depth of buried Precambrian hills.

This investigation is limited to buried and resurrected Precambrian hills of the Central Ozarks. It is concerned primarily with the structure and stratigraphy of sediments adjacent …


The Anodic Behavior Of Zinc In Aqueous Salt Solutions, Yun-Chung Sun Jan 1966

The Anodic Behavior Of Zinc In Aqueous Salt Solutions, Yun-Chung Sun

Doctoral Dissertations

"The increasing demand for protective metals as coatings and non-corrosive alloys has caused extensive research on the fundamental behavior of metals in corrosive media. The problem of controlling the destructive process of metallic corrosion still exists and becomes urgent in this space age. The desirablity of metals such as beryllium, magnesium, and zinc in air frame and space structural units, because of their high strength to weight ratio, has been responsible for the considerable progress in their technology in recent years.

The basic mechanism of the anodic dissolution of metals such as zinc, cadmium, and magnesium in salt solution is …


Re-Evaporation Nuclei And Evaporation In A Wilson Cloud Chamber, James G. Smith Jan 1966

Re-Evaporation Nuclei And Evaporation In A Wilson Cloud Chamber, James G. Smith

Doctoral Dissertations

"Experimental techniques are developed for observing droplet evaporation in the submicroscopic size range. An expansion-compression cloud chamber with an atmosphere of tank helium saturated with water vapor is employed. This work was undertaken with the aim of examining submicroscopic droplet behavior and the existence of re-evaporation nuclei, a form of memory effect.

The theories of evaporation and nucleation on submicroscopic drop residues were re-examined, and alterations which appear to be consistent with the results of this work were incorporated into the evaporation theory.

The observed continually decreasing evaporation rate with diminishing droplet size confirms the existence of re-evaporation nuclei, but …