Physical Sciences and Mathematics Commons^™

Realistic Impulsive P Wave Source In An Infinite Elastic Medium, Joseph Hugo Hemmann

Doctoral Dissertations

"The generally assumed instantaneous impulsive pressure sources for an elastic P wave in an infinite medium lead to basic contradictions, a step function source yielding infinite displacements as the shear modulus goes to zero, and the total energy radiated by a delta function (or any derivative of the delta function) source being infinite. By noting that the character of the solution in the elastic region must match the acoustic case near the source, a realistic impulsive pressure source is postulated which has a finite time history. The elastic field produced by this source is then obtained in closed form. A …

Search Algorithms For The Simple Plant Location Problem, John Bruce Prater

Doctoral Dissertations

"Two algorithms are developed, one exact, one approximate, for finding solutions to the simple plant location problem. Theorems are proved which give sufficient conditions for the inclusion of a plant in the optimal solution. The exact algorithm which is developed is similar to the Branch and Bound method. The approximate technique consists of a directed search through the solution tree for the problem, followed by terminal iterations. The terminal iterations are justified by empirical results obtained from a preliminary version of the technique and a theorem which is proved. Statistics from the results of applying the algorithm to a large …

Electrochemical Measurements In Molten Fluorides, Howard W. Jenkins

Doctoral Dissertations

The nickel (II) / nickel couple, contained in a boron nitrade compartment, was shown to be a useful reference electrode in fluoride melts. From emf measurements no nickel (II) / nickel concentration cells, the nickel (II) / nickel couple was shown to obey the Nernst equation in molten LiF-NaF-KF (46.5-11.5-42.0 mole per cent) and LiF-BeF₂-ZrF₄ (65.6-29.4-5.0 mole per cent). It was found that in some cases the reference electrode had a significant junction potential across the boron nitride wall.

Kinetics of the charge transfer reaction Ni(II) + 2e = Ni were investigated by the voltage-step method. Apparent …

Longitudinal Optical Phonon-Plasmon Coupling In Ionic Semiconductors, Thomas Joseph Mcmahon

Doctoral Dissertations

"The coupling of free carriers and lattice vibrational modes is studied in CdS and InSb by room temperature far infrared reflectance measurements. When the free carrier concentration is such that the plasma frequency is at or near the longitudinal optical mode frequency it is shown that while the transverse modes remain fixed, the longitudinal modes mix with the plasma mode and are shifted in a manner similar to that described by Varga in 1965. Using the dielectric function for the coupled system permits the determination of electron effective masses by reflectance measurements with lattice effects excluded. This method allows one …

Noble Gases: A Record Of The Early Solar System, E. C. Alexander

Doctoral Dissertations

"Analyses of the noble gases in samples of iron meteorites are presented which indicate the following: 1. The inclusions of iron meteorites contain noble gases with a wide range of isotopic compositions. 2. The noble gas concentration and isotopic anomalies arc often grossly inhomogeneously distributed within a given inclusion and vary from inclusion to inclusion in a meteorite. 3. Silicate inclusions appear to be the most promising samples for I-Xe and Pu-Xe dating. 4. Graphite and troilite in addition to the silicate inclusion contain significant radiogenic ¹²⁹Xe anomalies. 5. The total I-Xe (and in the case of Toluca silicates total …

Statistical Inferences For The Cauchy Distribution Based On Maximum Likelihood Estimators, Gerald Nicholas Haas

Doctoral Dissertations

"Various estimators of the location and scale parameters in the Cauchy distribution are investigated, and the superiority of the maximum likelihood estimators is established. Tables based on maximum likelihood estimators are presented for use in making statistical inferences for the Cauchy distribution. Those areas considered include confidence intervals, tests of hypothesis, power of the tests, and tolerance intervals. Both one- and two-sample problems are considered. Tables for testing the hypothesis of whether a sample came from a normal distribution or a Cauchy distribution are presented. The problems encountered in finding maximum likelihood estimators for the Cauchy parameters are discussed, and …

A Theoretical Study On The Interpretation Of Resistivity Sounding Data Measured By The Wenner Electrode System, Siew Hung Chan

Doctoral Dissertations

"This thesis deals with a theoretical study on the interpretation of resistivity sounding data measured by the Wenner electrode system. The objectives of this investigation are twofold: (i) to derive from the apparent resistivity data some suitable functions from which the resistivity and thickness of each member of the sequence of layers composing the earth may be determined, and (ii) to devise suitable methods for analyzing the resulting functions. In this investigation it is shown that the solution of the boundary value problem associated with an n-layered earth model leads to an integral equation for the Wenner electrode system. This …

A Study Of The Energy Loss Spectra Induced By Impact Of 23-125 Kev Protons On Helium Atoms, Franklin Dean Schowengerdt

Doctoral Dissertations

"Results of a study of the inelastic energy loss spectra induced by the impact of protons on gaseous helium at energies of 25 to 125 keV are reported. The spectra were obtained by sending an accelerated beam of protons through a chamber containing the helium target gas, mass-analyzing the forward-scattered beam, then decelerating the beam to a low, well-defined energy for energy analysis and detection. The accelerating potential was varied to produce the spectra. An energy resolution of 2 eV was obtained. Apparent differential cross sections and absolute total cross sections were obtained from the spectra. Total cross sections for …

Statistical Inferences For The Generalized Gamma Distribution, Harold Walter Hager

Doctoral Dissertations

"Procedures for handling statistical problems with nuisance parameters are considered with special reference to problems in the three parameter generalized gamma distribution. Maximum likelihood estimation of the parameters of this density has been investigated. Properties of these estimates are established which make it possible to make inferences about the parameters. Discrimination between various models for life testing problems is discussed and the robustness of the Weibull model is advanced. The question of the existence of the maximum likelihood estimates of the parameters for all samples is raised. Empiric evidence is presented indicating that they may not exist for all small …

The Statistics Of Finite, One Dimensional Lattice Fluids, John Roger Glaese

Doctoral Dissertations

"A one dimensional lattice fluid in which particles are allowed to assume only discrete positions is proposed. Particles are free to move from one lattice site to another interacting through a variety of potentials, including the Lennard-Jones type. The model allows the partition function to be evaluated as a discrete sum over the allowable configurations. Both the canonical ensemble and grand ensemble are treated by computer and a third, the pressure ensemble, is considered and shown to be useful in the theoretical treatment of lattice systems. The thermodynamic behavior of various systems is investigated in both the canonical and grand …

A.C. Hall Effect Measurements On Very High Resistivity Materials Exhibiting Electrode Polarization, James Dale Boyd

Doctoral Dissertations

"A variable frequency, a.c. Hall effect measurement technique has been designed for mobility studies in very high resistivity (>10⁹ ohm·cm) materials exhibiting electrode space charge polarization effects. It incorporates a neutralized input capacitance preamplifier detector which reduces the total input shunting capacitance, including the sample interelectrode capacitances, to a very low, definable value (<0.1 pf) and thereby provides very high and well defined a.c. detector input impedances (4 x 10⁹ and 7 x 10⁹ ohms at 600 and 200 Hz, respectively). Lumped parameter equivalent circuits have been defined to approximate the electrical behavior of sample materials in the measurement configuration. These equivalent circuits, together with independent measurements of the detector input and sample impedances, allow one to correct the detected Hall voltage and obtain the true value from which mobility data may be derived. The validity of these circuits has been established by independent a.c. and d.c. measurements on photoconductive CdS (dark resistivity >10¹⁰ ohm·cm) which exhibited maximum differences of less than 4%. The existing literature has been critically reviewed and the measurement criteria established by this study have been applied to resolve differences in reported data and to suggest improvements in the resolution of previously employed experimental …

Vapor Phase Clustering Model For Water, Richard W. Bolander

Doctoral Dissertations

"Although nucleation phenomena are among the most widespread of all naturally occurring phenomena, even the simplest of nucleation processes, homogeneous nucleation, is poorly understood, particularly the homogeneous nucleation of liquid droplets from water vapor. Homogeneous nucleation involves only molecules of a single substance and does not include the complicating effects due to a substrate or piece of foreign matter. The semiphenomenological liquid drop theories developed nearly three decades ago differ in relatively minor details, with the crucial element of the theory being the derivation of the free energy of formation of the clusters. The clusters are viewed as well-defined incompressible …

A Five Parameter Study Of Spherical Transient Waves In A Generalized Voigt Model, Liang-Juan Tsay

Doctoral Dissertations

"Transient spherical waves in a generalized Voigt model were investigated in this study. Both Laplace and fourier transform solutions of the spherical wave equation for a generalized Voigt model were obtained by means of the correspondence principle. Laplace transform solutions were inverted numerically into the domain for the study of the characteristics of the wave forms, and Fourier transform solutions were utilized for the analysis of frequency dependency attenuation in the models. Generalized Voigt models A and B in which a dashpot is connected in series with spring and dashpot components were unable to represent a solid which would simulate …

Characterizing Topologies By Continuous Selfmaps, Derald David Rothmann

Doctoral Dissertations

"Various topological spaces are examined in an effort to describe topological spaces from a knowledge of their class of continuous selfmaps or their class of autohomeomorphisms. Relationships between topologies and their continuous selfmaps are considered. Several examples of topological spaces are given and their corresponding classes of continuous selfmaps are described completely. The problem, given a set X and a topology U when does there exist a topology V either weaker or stronger than U such that the class of continuous selfmaps of (X,V) contains the class of continuous selfmaps of (X,U), is considered. M* and S** spaces are defined …

Low-Lying Levels In Some Spherical And Rotational Nuclides By Coulomb Excitation And Radiative Capture Of Thermal Neutrons, Donald Allan Mcclure

Doctoral Dissertations

"The work presented in this dissertation was performed in order to obtain additional information on the level schemes and decay properties of several nuclei in an attempt to explain the observations in terms of an applicable nuclear model. Various nuclear models are discussed in Section II. A general review from the classical point of view of the Coulomb excitation reaction is discussed in Section III and the thermal-neutron-capture reaction is outlined in Section IV. The experimental equipment and procedure is discussed in Section V in which the ramper method of energy determination is outlined. This method allows the measurement of …

MöSsbauer Effect Studies Of Ferroelectric Phase Transitions In The Pbzro₃ - Pbtio₃ - Bifeo₃ Ternary System, James P. Canner

Doctoral Dissertations

"The Mössbauer Effect was used to measure the phase transitions in the following ferroelectric compounds: 95% PbZ4₀.₈Ti₀.₂ - 5% BiFeO₃ [and] 95% PbZ4₀.₇Ti₀.₃ - 5% BiFeO₃ and in the antiferroelectric compound: 95% PbZrO₃ - 5% BiFeO₃. The parameters obtained were the area under the resonance peak, the isomer shift, and the electric quadrupole splitting, all as a function of temperature. The ionicity, electric field gradient, and Debye temperature were determined for room temperature. The data are discussed in terms of the lattice vibration model of ferroelectrics and antiferroelectrics, and the structural phase transitions as recently defined for these compounds. The …

Radiative Lifetime Of The B¹Σ⁺ And B³Σ⁺ States Of Carbon Monoxide, John Robert Rogers

Doctoral Dissertations

"The radiative lifetimes of the B¹Σ⁺ and b³Σ⁺ excited states of carbon monoxide were measured at six different pressures: 10, 25, 50, 75, 100, and 125 microns of Hg. The lifetimes were obtained by observation of the radiative decay of the (0,0), (0,1), (0,2), and (1,1) bands of the Angstrom system and the radiative decay of the (0,1), (0,2), (0,3), and (0,4) bands of the Third Positive system. No pressure dependence of the lifetimes was observed for either system. The average lifetime of the v' = 0 vibrational level of the B¹Σ⁺ state was found to be 24.4 x 10⁻⁹ …

Statistical Inferences For Location And Scale Parameter Distributions, Robert Henry Dumonceaux

Doctoral Dissertations

"The problem of discriminating between two location and scale parameter distributions is investigated. A general test based on a ratio of likelihoods is presented. A test based on a Pearson Goodness of Fit statistic is also considered. Tables are given for discriminating between the normal and exponential, the normal and double exponential, the normal and extreme value, and also between the normal and logistic. For location and scale parameter distributions, two-sided tolerance limits are shown to always be obtainable by Monte Carlo simulation. A method for obtaining confidence intervals on the reliability at a fixed time t is also given. …

The Deamination Of Deuterated-2-Hydroxy-2-Phenyl-3-Aminonorbornanes, Michael D. Eckart

Doctoral Dissertations

2-endo-Hydroxy-2-phenyl-3-endo-aminonorbornane-5,6-exo-d₂ was synthesized and subjected to nitrous acid deamination in glacial acetic acid. From the cationic rearrangement reaction eight products were isolated by liquid elution chromatography and identified by nuclear magnetic resonance spectroscopy. 2-exo-Hydroxy-2-phenyl-3-endo-aminonorbornane was also synthesized and deaminated under similar conditions. The product yields from this compound as well as the product yields from the 2-endo-hydroxy amine were determined by vapor phase chromatography.

From an examination of the deuterium distribution in the products of the deuterated amine and from the yields of products from both amines it was possible to construct a reasonable reaction sequence for the deamination …

An Experimental Determination Of The Homogeneous Nucleation Rate Of Water Vapor In Argon And Helium, Louis Benton Allen

Doctoral Dissertations

"An expansion type cloud chamber was used to measure the nucleation rate of water vapor in an atmosphere of helium and argon. A careful study was made of the thermodynamic characteristics during the expansion so that the nucleation data could be interpreted with reasonable accuracy and consistency. A fine wire thermocouple was used to measure the gas temperature during the course of an isentropic expansion in the dry chamber. When the finite heat capacity of the thermocouple is accounted for, it is found that there is almost perfect agreement with the temperature calculated from the equation of state and the …

Analysis Of A Focus Log Electrode In A Non Homogeneous Medium, John Julian Zenor

Doctoral Dissertations

"The mathematical model presented for the focused logging system is applicable to any resistance logging tool of the electrode type. Horizontal or cylindrical resistance interfaces may be included in any combinations. The tool and its environment are compartmentalized, and the integral form of the condition for continuity of current is applied to each compartment. Acceleration methods are applied to the iterative solution of the resulting large-scale system of linear equations. Two specific models are presented, one for the study of the effects of invasion and the other for the study of the effects of bed thickness on the apparent resistivity …

The Lifetime And Effective Quenching Cross Section Of The 6²P₃/₂ State Of Thallium, Robert Charles Pickett

Doctoral Dissertations

"The measurement of the lifetime of the metastable 6²P₃/₂ state of thallium is discussed. Measurement of time varying optical absorption by time sampling techniques is explained for the study of the decay of the metastable atom concentration following a pulsed radio frequency discharge. The decay of the thallium radiation from optically allowed states terminating on the metastable state is measured at nine different thallium densities in the afterglow of the discharge. This radiation repopulates the metastable state and is displayed on an oscilloscope. The metastable lifetime is measured as a function of the thallium density at three different r-f power …

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 …

Hrva - A Velocity Analysis Technique For Seismic Data, John Charles Robinson

Doctoral Dissertations

"A High-Resolution Velocity Analysis (HRVA) has been developed for the determination of the root-mean-square subsurface-velocity energy spectrum from gated seismic data which has been normal-moveout corrected. All calculations are performed in the frequency-space or frequency-wavenumber domain; seismic gates are transformed from the time-space domain via the Fast Fourier Transform algorithm. HRVA is not restricted to the investigation of apparent horizontal velocities which have associated stepout values that are integral multiples of the time sampling interval, as are the existing correlation techniques. The technique liberally exploits the inexistence of significant energy in the higher frequency harmonies of seismic data, resulting in …

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, k_H/k_D, 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

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 …

A Study Of Succinic Dehydrogenase, Indole Acetic Acid Oxidase, Nitrate Reductase And Cytochrome C Reductase In Hygrophorus Conicus, Jagdish M. Mehta

Doctoral Dissertations

"The activity of the enzyme succinic dehydrogenase (succinate : phenazine methosulfate oxidoreductase, EC 1.3.99.1) of Hygrophorus conicus, a member of a class of fungi known as basidiomycetes, was found to be stimulated by nitrate. Two substances were tested as electron acceptors in the measurement of succinic dehydrogenase activity. Of the two substances tried, phenazine methosulfate and brilliant cresyl blue, the former was found to be the best. Nicotinamide adenine dinucleotide (NAD⁺) was a necessary cofactor for the enzyme and could be readily dissociated from the enzyme. The enzyme has the properties of a high molecular weight nucleo- or lipoprotein.

The …

Synthesis And Properties Of Diorganomagnesium Compounds, Conrad William Kamienski

Doctoral Dissertations

Introduction: Although dialkylmagnesium compounds have been known for over a hundred years, relatively little effort has been directly expended on these reagents per se; much of what we know about magnesium alkyls has been an outgrowth of previous studies concerned with the nature of the Grignard reagent. Only recently has any effort been made to elaborate on methods for preparing these reagents, to determine carefully their physical and chemical properties, and to develop practical uses for these reagents. It has been the purpose of the present study to review the presently known methods of preparation of dialkylmagnesium compounds, to …

Minimal Weinstein Discs In A Subspace, William Lewis Morris

Doctoral Dissertations

The basic features of Clanton's algorithm are reviewed and it is shown that the analysis of ρ(A; Sx) leads to a refinement of the algorithm. A new algorithm to solve Ay = λy is the concluding item in this investigation

Lithostratigraphy Of Conasauga Group Between Rogersville And Kingsport, Tennessee, Walter Lee Helton

Doctoral Dissertations

Conclusions: The following conclusions are presented from the study of the lithostratigraphy of the Conasauga Group in Carter and Stanley valleys:

1. The Conasauga Group presents classic examples of isopic and heteropic facies.

2. The lithology of the individual formations of the Conasauga Group is remarkably similar in both thrust belts.

3. The carbonate units of the Conasauga Group thicken eastward and southeastward and the claystone units thicken westward and northwestward.

4. The Pumpkin Valley Shale is a transitional unit which has a Rome lithology in the lower half of the formation and Conasauga-type lithologies in the upper one-half of …