Physical Sciences and Mathematics Commons^™

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 Determination Of The Speed Of Light By The Phase-Shift Method, John Rogers, Ronnie Mcmillan, Robert Pickett, Richard A. Anderson

Physics Faculty Research & Creative Works

A low-frequency, phase-shift method for the measurement of the speed of light has been developed. This technique gives results commensurate with other advanced laboratory methods. One advantage of this technique is that the apparatus is of reasonable size and most of the circuitry involves widely known amateur radio techniques. Furthermore, our use of a low modulating frequency permits use of the solid-state, electro-optical light shutter. This eliminates the rather dangerous liquid Kerr cell, thus making our apparatus more acceptable to application in the undergraduate advanced laboratory. From a pedagogical point of view, the student is allowed to use and become …

Semiempirical Determination Of The Hydrogen Bond Energy For Water Clusters In The Vapor Phase. I. General Theory And Application To The Dimer, Richard W. Bolandee, James L. Kassner, Joseph T. Zung

Physics Faculty Research & Creative Works

A simple semiempirical method is given for determining the hydrogen bond energy for water clusters in the vapor phase. This method is based on a general statistical-mechanical theory of clustering. The partition function for a system of clusters is used to determine the equilibrium distribution of clusters. In conjunction with available thermodynamic and spectroscopic data, the cluster equilibrium constants can be used to calculate the cluster potential energy and the hydrogen bond energy. Results for the water dimer agree quite well with other reported values obtained either by quantum-mechanical calculations or approximate thermodynamic estimates. A correct temperature dependence of the …

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 …

Infrared Cooling Near Atmospheric Temperature Inversions And Absorber Concentration Variations, Joey Keith Tuttle

Masters Theses

"Cooling due to infrared radiation near temperature inversions is investigated. Temperature inversions tend to hold pollution below the inversion level. The pollution itself may contribute to the stability of the inversion by selectively cooling certain portions of the atmosphere. A method is developed for evaluating infrared cooling rates at discreet points in the atmosphere. Several sample calculations are given to demonstrate the effects of variations of absorber concentration and lapse rate"--Abstract, page i.

An Experimental Comparison Of Various Nuclei Counters, Joel William Mansell

Masters Theses

"A series of simultaneous nuclei concentration measurements, with four different nuclei counters, have been made. these counters were a Pollak and a Gardner counter supplied by Mr. Paul Allee of the Environmental Science Services Administration, Boulder, Colorado, and a Pollak and a G.E. counter supplied; by Mr. Norman White of the National Center for Air Pollution Control, Cincinnati, Ohio. In the absence of any knowledge of the absolute concentrations in the samples, the data for each of the individual counters have been compared to the averages computed from all four counters. The results of these comparisons indicate the following: (1) …

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

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 …

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. …

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

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.

Rotational Excitation Of Polar Molecules By Electrons, Marvin H. Mittleman, Jerry Peacher, Balazs F. Rozsnyai

Physics Faculty Research & Creative Works

Rotational excitation of polar molecules is calculated in the approximation that the electron transit time is short compared with rotational periods with the result of an E^-1 behavior of the cross section. Diffusion cross sections are calculated for Δl=0,1,2. Significant corrections to the Born approximation are obtained for large dipole moments. The range (in energy) of applicability of the result is discussed in terms of the energy dependence of the corrections, and a novel energy dependence of these corrections is encountered and explained.

Measurement Of Positron Annihilation Line Shapes With A Ge(Li) Detector, H. (Henry) P. Hotz, J. M. Mathiesen, J. P. Hurley

Physics Faculty Research & Creative Works

We observed that the annihilation radiation photopeak in a Ge(Li) detector is considerably broader than that of a γ ray of the same energy. It seems reasonable to assume that the increased width is the result of the Doppler broadening of the annihilation photopeak, i.e., the longitudinal Doppler shift of the radiations is measured, while the transverse shift is measured in the usual angular-correlation experiments. By using a computer stripping program to remove the distortion produced by the finite energy resolution of our detector, we obtain momentum distributions in agreement with those which have been published. Only one detector is …

Longitudinal Optical Phonon-Plasmon Coupling In Cds, Robert John Bell, Thomas J. Mcmahon, Donald G. Rathbun

Physics Faculty Research & Creative Works

The longitudinal optical phonon-plasmon interaction theory of Varga is shown to be applicable to Gadoped CdS through the region of the first reflectivity minumum (2.5 to about 30 μ). The theoretical reflectivity vs wavelength for several concentrations of Ga-doped CdS are compared with experiment. The agreement between theory and experiment is particularly good for high dopant concentrations. A plot of the wavelength at minimum reflectivity vs impurity concentrations shows that the Varga theory does well in explaining the data. When phonon damping is introduced into the Varga dielectric function, the reflectivity over the whole region of resonance is more realistic. …

Modified Phase Representation And Effects Of Inelasticity In N/D Calculation Of P-Wave Pion-Pion Scattering, Barbara N. Hale, Arnold Tubis

Physics Faculty Research & Creative Works

An N/D formalism based on a modified phase representation is used to study the effects of inelasticity on the ρ-wave pion-pion amplitude. The effects of high-energy inelasticity are introduced in terms of the assumed behavior of the high-energy phase (not phase shift) of the partial-wave amplitude. Using a ρ-exchange input force with the experimental ρ mass and a ρ width of about 100 MeV, and the assumption that the average phase is (1/2)π, for total c.m. energies greater than about 8M_π, we find that there is no appreciable reduction in the width of the calculated ρ-wave resonance. We …

Critical Assessment Of The Polarized-Orbital Method In Atomic Scattering, Marvin H. Mittleman, Jerry Peacher

Physics Faculty Research & Creative Works

The method of polarized orbitals used in calculating electron-atom scattering amplitudes has two obvious flaws: the wave function is discontinuous, and the method is not variationally based. These are corrected in a somewhat arbitrary manner, and it is found that the results then depend upon a parameter of the theory sufficiently strongly that there are serious doubts about the predictive nature of the theory.

Modified Dispersion Relations And Π Π Scattering, David J. George, Barbara N. Hale, Arnold Tubis

Physics Faculty Research & Creative Works

The ππ S-wave scattering-length predictions of Weinberg have been tested by using dispersion sum rules for the infinite-energy cross section. Reasonable agreement is obtained with the infinite-energy cross section (≈15 mb) estimated from the factorization theorem for the Pomeranchon Regge residues. Experimental phase-shift data of Gutay et al., Walker et al., and Baton et al. are used in estimating the dispersion integrals. The analysis seems to rule out an I = 0 S-wave scattering length ⪞0.4μ^-1.

The Atlantic Continental Margin, Bruce C. Heezen

UMR Journal -- V. H. McNutt Colloquium Series

Turbidity currents, surface, and subsurface currents carry detritus from the land across the continental shelf to the adjacent continental slope where slumps and turbidity currents transport the sediment downslope for hundreds of miles to greater depths, and deep geostrophic contour currents transport it thousands of miles down-current in a direction parallel to the bathymetric contours. The combined effect of these processes has been to create a wide, thick, geosynclinal apron of sediment at the base of the continental slope.

Subsidence of the continental shelf has continued since mid-Mesozoic, carrying down Lower Cretaceous reefal limestones to depths of 5,000 meters off …

Major Structures Of The Rocky Mountains Of Colorado And Utah, A. J. Eardley

UMR Journal -- V. H. McNutt Colloquium Series

This paper describes the major structures of Colorado and Utah and presents a theory of origin based on new knowledge of the layering and constitution of the upper mantle and lower crust. It proposes that the Ancestral Rockies and the more modem ones of Cretaceous and early Tertiary age of both the shelf of Colorado and eastern Utah and the miogeosyncline of western Utah are the result of vertical uplifts of the silicic crust. The uplifts are caused by the rise, from the upper mantle, of basalt in scattered places to the base of the silicic crust. This rise domed …

Tectonic Framework Of The Great Basin, Ralph J. Roberts

UMR Journal -- V. H. McNutt Colloquium Series

The Great Basin is bordered on the west by the Sierra Nevada and on the east by the Colorado Plateau and Rocky Mountains. These tectonically different provinces are genetically related; basin and range structure evolved as part of the tectonic development of western North America.

The Precambrian framework here is not well known, but northeasterly geosynclinal trends, east- west orogenic trends, and northwesterly fracture zones can be projected from the craton or inferred.

Sedimentation in the Cordilleran orthogeosyncline from Cambrian to Devonian time was characterized by an eastern miogeosynclinal (carbonate) and a western eugeosynclinal (siliceous and volcanic) assemblage. In latest …

Geologic Structure And History Of The Sierra Nevada, Paul C. Bateman

UMR Journal -- V. H. McNutt Colloquium Series

The Sierra Nevada is a huge block of the earth’s crust that has broken free on the east and has been tilted westward. It is composed chiefly of Mesozoic granitic rocks and Paleozoic and Mesozoic metamorphosed sedimentary and volcanic rocks. The granitic rocks constitute the Sierra Nevada batholith, which is part of a more or less continuous belt of plutonic rocks that extends northward from Baja California through the Sierra Nevada at a small angle to the axis of the range and into western Nevada. The batholith is localized in the axial region of a complexly faulted synclinorium. It is …