Digital Commons Network^™

Modified Method Of Linear Associative Retrieval, James Donald Byrd

Masters Theses

"It is becoming increasingly important for those in decision making positions to have the most current and accurate data possible as related to their particular needs. Although there are several well known retrieval techniques available an intensified effort is being made at many installations to provide a retrieval system that will supply the demands of their own needs. One well known approach to the solution of information retrieval is linear associative retrieval. The solution that has been proposed requires several computer runs on some requests and therefore is very time consuming. The author has implemented a method to eliminate unnecessary …

The Cathodic Reduction Of Bromate Ions On Mercury In Neutral And Basic Solutions, Jaw-Shin Chang

Masters Theses

"The reduction of BrO⁻₃ was studied in neutral and basic solutions on a stationary Hg surface under activation controlled conditions. Coulombic efficiency studies showed that BrO⁻₃; was reduced to Br⁻ with high efficiencies. The polarization measurements lead to a proposed reaction scheme which is consistent with the experimental observations"--Abstract, page 1.

An Approximate Min-Max Solution To The Identification Problem, Richard Loyd Warren

Masters Theses

"A technique based on the min-max error criterion is proposed for identifying a dynamic system in terms of a discrete-time model from the system response to a deterministic input. A linear, single-input/single-output, lumped-parameter, time-invariant (at least during the measurement interval) system is assumed. Although the resulting problem is non-linear, it is shown that linear programming techniques are applicable if a realistic approximation is made. The technique is implemented on the digital computer and evaluated by considering a number of typical discrete-time systems. The effects of additive noise are also considered"--Abstract, page ii.

The Design And Construction Of An Inertia Welder, Arthur Ferdinand Grimm

Masters Theses

"The purpose of this investigation was the design and fabrication of a machine to bond metal to metal using the inertia method of friction welding. This method of bonding is considered far superior to the heretofore employed friction welding processes as will be explained later. The inertia method controls the energy imparted to the weld by using a flywheel which has been brought to a state of predetermined kinetic energy due to rotation. This energy is then transferred to the weld zone in the form of heat due to rotational friction. Hollow specimens with a cross-sectional area of 0.306 square …

A Proposed Concept For The Rapid Field Design Of Protective Structures, John Ross Childress

Masters Theses

"This investigation proposes a simplified concept for the rapid field design of protective structures, subject to attack by conventional artillery rounds, mortar rounds and small rockets. Parameters which should be considered during a rigorous design process are discussed. The number and complexity of these parameters make the rigorous design procedure too unwieldy to be efficiently used, in a limited time period, when materials are not available to comply with Standard Designs. Since the duration of an explosion pulse is very short and uncompacted soil is capable of absorbing explosive energy, this study investigates the theory that adequate protection can be …

A Permeability Scaling Technique In The Numerical Simulation Of Water Coning, Virendra Kumar Dutta

Masters Theses

"A two-dimensional, two-phase, radial, horizontally layered water coning simulator was programmed for large memory digital computers. A permeability sealing technique is developed which allows the use of large size blocks as production blocks. As a result of this technique large time steps have been used without causing saturation instabilities around the well bore and the permeability scaling technique allows a more realistic simulation of a water cone. The IMPES method is used to calculate pressure and saturation in the system for each finite time step. The behaviour of the simulator is studied for various factors affecting the advance of a …

Structures And Relationships Of Some Perovskite-Type Compounds, Christian Michel

Doctoral Dissertations

"A model for crystallographic transitions in perovskites is proposed. The model consists of regular octahedra sharing corners and topologically able to rotate without distortion around their three-fold axes. This model, with R3̄c symmetry (18e position) can be described in terms of a continuous rotation of angle, w, of octahedra from two ideal symmetry forms: the hexagonal close-packed and the cubic face-centered configurations. A parametric relation is derived between w and the rhombohedral cell angle, α, or the corresponding hexagonal axial ratio c/a . A wide range of atomic structures based on a framework of regular or slightly distorted octahedra sharing …

The Electrochemical Behavior Of The Lead-Thallium System In Acidic Sulfate Solutions, Pedro Juan Aragon

Doctoral Dissertations

"Although the literature involving the corrosion of pure lead in sulfuric acid solutions is extensive, such studies still constitute an active field of investigation and debate. Much of the effort expended on this subject is due to the need of a better understanding of the reaction in lead storage batteries as well as of the mode of electrocrystallization processes. The resistance of lead to attack by sulfuric acid renders it an important coating material in this media. It is also often used in electrochemical synthesis because of its overvoltage characteristics. Unfortunately its mechanical properties are poor, and many ways have …

Substitution And Photolytic Rearrangements In Three-Member Ring Compounds, Joseph Terril Bohanon

Doctoral Dissertations

"An investigation into the substitution and photolytic rearrangements of 1,2,3-triphenylcyclopropenes was conducted. Triphenylcyclopropenyl t̲-butyl ether was found to undergo alkyl group exchange with refluxing methanol, ethanol, or 2-propanol to yield the corresponding 1,2,3-triphenylcyclopropenyl alkyl ether when a trace impurity of a 1,2,3-triphenylcyclopropenium halide is present to catalyse the reaction. This forms hydrogen halide with solvent. Upon standing for long periods of time, the 1,2,3-triphenylcyclopropenyl ethers were observed to partially rearrange to new products. A sample of 1,2,3-triphenylcyclopropenyl methyl ether was subjected to photolysis in hexane and yielded 3-methoxy-1,2-diphenylindene, 2,3- diphenylindenone, tolane, benzoic acid, 1,2,3-triphenylpropen-1-one and a polymer. Samples of 1,2,3-triphenylcyclopropene, …

The Cathodic Reduction Of Maleic Acid, Show Yih Hsieh

Doctoral Dissertations

"The electrochemical reduction of maleic acid (0.0003 to 0.3 M) was studied on Hg, 0.5% Bi(Hg) amalgam, 5.0% Bi(Hg) amalgam, and Bi cathodes in 1 n H₂SO₄-K₂SO₄-KOH electrolytes (pH 0.3 to 4.0) at 60°C. The maleic acid was converted to succinic acid with high efficiencies (86 to 100%) on all cathodes. Polarization curves with linear Tafel sections were found. All the cathodes had similar kinetic parameters...A reaction mechanism consistent with the experimental observations is proposed..."--Abstract, pages ii-iii.

Temperature Variation In Distribution Of Relaxation Times In Aluminosilicate Glasses, David Wayne Moore

Doctoral Dissertations

"The distribution of relaxation times for the alkali peak in a Li₂ O·A1₂O₃ ·2.0SiO₂ glass and for the mixed alkali peak in a 0.5Li₂O·0.5Na₂O·A1₂O₃·2.OSiO₂ glass was studied using the internal friction technique. A lognormal distribution of relaxation times provided the best agreement with the experimental data. The ß parameter of the lognormal distribution function, which is related to the half-height peak width, varied with temperature, indicating that the distribution of relaxation times is dependent upon the activation energy and the activation entropy of the relaxation mechanism. The major contributor to the distribution of relaxation times is a wide distribution in …

The Deformation Mechanisms In Sublimed Magnesium Under Cyclic Loading, Babu Narian Thakur

Doctoral Dissertations

"A detailed study of the deformation processes in sublimed magnesium under reverse bending fatigue in air at room temperature has been undertaken utilizing the light, scanning and transmission electron microscopy. The Principal deformation modes are the basal slip and {10Ī2} twinning. The proportion of twinning increases markedly with the increasing stress level and the number of cycles. The evidence for cross slip is seen on the basal slip bands. The extrusions are seen not only along the basal slip lines but also along the {10Ī2} twin boundaries. In the later stages of fatigue, the extrusions chip off producing a notch …

The Electrochemical Oxidation Of 1-Pentyne On Platinum And Gold, Michael Jensen Danielson

Doctoral Dissertations

"The anodic oxidation of 1-pentyne was studied at 70°C on Pt and Au electrodes in solutions of H₂SO₄, K₂SO₄, K₂CO₃, and KOH. Pt was studied in a pH range of 0.35 - 12.7 and Au in a range of 10.9 - 12.7. Reaction rates were measured as a function of potential, pH, temperature, and 1-pentyne partial pressure. The coulombic efficiencies for the oxidation to CO₂ were 77 percent in 1 N H₂SO₄ and 69 percent in 1 N KOH on Pt and 43 percent in 1 N KOH on Au. The kinetic parameters on Pt were [partial derivative]V/[partial derivative]log i …

Glory Scattering In Molecular Collisions: Formal Expressions For The Total Cross Section, Louis Biolsi

Chemistry Faculty Research & Creative Works

An Extended Distorted-Wave Treatment is Used to Obtain Formal Expressions for the Total Cross Section When Two Rigid Diatomic Molecules with Orbital and Nuclear-Spin Angular Momenta Collide. Explicit Expressions Are Obtained through Second Order, Including the Lowest-Order Inelastic Effects.

Electric Field Strength Dependence Of Surface Damage In Oxide Passivated Silicon Planar Transistors, C. A. Goben

Electrical and Computer Engineering Faculty Research & Creative Works

A dependence of surface degradation induced by ionizing radiation in matched oxide-passivated silicon planar epitaxial transistors on junction fringing electric field strength present during exposure is reported. The electric field strength and gamma dose dependence are investigated of the decrease in the forward current gain, hFE (as reflected by the increase in the surface recombination current component), the increase in the surface recombination velocity (as reflected by the increase in the reciprocal of the minority carrier lifetime), and the increase in junction capacitance. Empirical prediction equations have been derived, for matched devices, correlating the normalized base current increase and the …

Baseband Agc In An Am-Fm Telemetry System, Richard S. Simpson, William H. Tranter

Electrical and Computer Engineering Faculty Research & Creative Works

The use of AGc loops at the input and output of the FM link in an AM-FM telemetry system allows the mean-square transmitter deviation to be maintained near maximum value, even though data may be nonstationary. However, errors result because of the inability of the receiver AGc loop to track perfectly gain variations in the transmitter loop. In this paper the general characteristics of AGc are discussed, and a theoretical analysis is performed to determine the time constant, steady-state error, and tracking error for a first-order loop. Also, tracking error for first order and second-order loops is investigated by simulation. …

Evaluation And Application Of Dye Tracers In Karst Terrain For Determining Aquifer Characteristics, Milton Frank Bradley

Masters Theses

"As ground water becomes increasingly important as a source of water in the United States, reliable information on the hydrological characteristics of carbonate aquifers must be obtained in order to develop them intelligently. Various tracers have been used in the past to determine if two or more points are connected hydrologically. Today there exists a number of excellent dye tracers and tracer methods have been developed in unconsolidated and clastic aquifers for determining hydrological characteristics. This paper reviews the various dye tracers and methods which might be applied in a carbonate karst terrain using wells as injection and sampling points. …

Penetration In A Graded Filter, William Chuan Shen

Masters Theses

"An experimental laboratory study conducted to examine clogging within and penetration of fines into a single layer graded filter. Hydraulic gradient, filter gradation and flow direction were varied. Forty one tests gave over six hundred individual penetration depths. The magnitude of penetration in filters with considerable variation in gradation patterns correlated with an average hydraulic radius based on the volume of voids and an approximated total surface area. It has been shown than an increased thickness of poorly graded filter will stop penetration such as that caused by seepage erosion. A relationship between hydraulic radius, penetration depth and probability of …

A Study Of The Composite Action Of Light Gage Steel Deck And Concrete, Charles Sherman Bach Jr.

Masters Theses

"This thesis is on the investigation of corrugated light-gage steel sheets used as the tension reinforcement for concrete slabs. The steel sheets used had embossments placed at uniform intervals over the entire length of the sheets. The composite concrete and light-gage deck steel were tested to determine a method of design for this type of composite section from an economical, safe and practical standpoint. The investigation covered the flexural, shear and bond capacity of this type of composite section"--Abstract, page ii.

Mass Spectrometric Study Of "Anomalous" Water, Bernard Jean Bouy

Masters Theses

"Considerable interest has developed recently in a material called "polywater" or "anomalous water". This material has properties quite different from those normally associated with liquid water. The purpose of this study is to give some mass spectrometric observations of "polywater". The "polywater" samples were produced within silica capillaries. These capillaries were heated by means of a helical coil to vaporize the "polywater". The vapor was directed into the source of a mass spectrometer. The results of this study show that a significant portion of the "anomalous water" samples is composed of a polymer of dimethylsiloxane. To date, the observations are …

Evaluation Of Cascaded Inertial Vibration Isolation Systems, Rajnikant Bhikhabhai Patel

Masters Theses

"Cascaded inertial vibration isolation systems are examined in this report. Systems employing one, two or three masses in series on isolators are investigated. The objective is to determine if the cascaded systems have appreciable advantages over the classical single mass system. The equations of motion for these systems are derived by applying Newton's second law of motion. The homogeneous and steady state sinusoidal excitation solutions have been established. Transmissibility of forces and moments to the foundation has been obtained for several cases of force excitation. Comparisons of the cases investigated are based upon the principal mode frequencies, mode shapes, center …

A Systematic Study Of Instrument Variables Upon The Accuracy Of Microprobe Analysis, R. A. Parr

Masters Theses

"The purpose of this investigation was to study the effect of instrument parameter changes upon X-ray intensity measurements of the copper-manganese system. The parameters utilized in this study included: (1) polished, contaminated, and 600 grit surfaces ; (2) constant sample current and constant beam current modes; and (3) 15 KV, 20 KV, and 25 KV accelerating potentials. Inspection of the data disclosed three interesting points: (1) copper and manganese X-ray intensity measurements appear to be a linear function of composition in the 15 KV through 25 KV accelerating potential range; (2) electron backscatter measurements consistently show in a limited range …

An Sem Surface Study Of Nucleate Pool Boiling Heat Transfer To Saturated Liquid Nitrogen Reduced Pressures From 0.1 To 0.9, David Virgil Porchey

Doctoral Dissertations

"This study constituted an examination of both nucleate boiling and maximum heat flux characteristics of liquid nitrogen boiling from characterized surfaces. Several textures of gold plated copper surfaces were studied in addition to silver and silver oxide surfaces. Data were taken over a wide range of reduced pressures. All surfaces were examined using a Scanning Electron Microscope (SEM). Data and micrograph comparison revealed that both surface chemistry and surface roughness affect the nucleate boiling characteristics of liquid nitrogen. These effects are separated from each other showing that nucleate boiling is a function of both surface chemistry and topography. Surface roughness …

Identification Of Decomposition Products Of Tropyl Azide And Interaction Of Tropylium Ion With Nucleophiles, James Joseph Ward

Doctoral Dissertations

"An investigation of the structures of several of the products resulting from the decomposition of tropyl azide (I) and of the chemistry of related processes has been undertaken. Irradiation of samples of (I) in the vapor phase with low intensity UV G.E. Sun Lamps furnished a low melting white solid identified as tropyl troponimmonium azide (II). Earlier experiments of a similar nature reported to furnish (III) were not repeatable (Chem. Commun 276 (1967))...

Upon standing, solutions of (I) slowly formed troponimmonium azide (IV) in the cold (J. Chem. Soc. (D), 220 (1970)). The structures (II) and (IV) were confirmed by …

The Surface Effects Of Alkali Halides In The Infrared, Vincent Joseph Llamas

Doctoral Dissertations

"The surface state extension of the shallow donor theory is reviewed. The surface state theory and its applications to F-centers of alkali halides is presented. Experimental infrared data show an absorption which seems to correspond with the ground state to first excited state transition. Surface state concentrations of F-centers as a function of depth into the crystal are given. The ratio of surface to bulk cross sections in KBr and experimental calculations of effective masses in various alkali halides are in excellent agreement with theory. The theoretical cross sections are derived from transition probabilities. However, lack of excited states, the …

Abandoned Automobiles :A Case History Of Land Pollution, Robert William Arden

Masters Theses

"A study has been made of the abandoned automobile problem as it now exists throughout the United States with particular emphasis on the problem in the Saint Louis area. The primary goal of this study was to determine those factors which most influence the collection and disposal of derelict vehicles. The problem was examined in the following major areas: (1) The history of the problem in the Saint Louis area and the various attempts made to correct it, (2) the various businesses directly involved with the disposal of junk automobiles, namely, the auto wreckers and the scrap processors, and (3) …

The Closed Cycle-External Combustion Engine And Air Pollution, Galen Lee Pearson

Masters Theses

"The impact of the internal combustion engine on the air pollution problem in this country was presented and alternative propulsion systems for the land transportation vehicle were investigated. The potential characteristics of the more promising closed cycle-external combustion engine concepts were established and discussed. The closed thermodynamic power cycles analyzed include the Rankine, Stirling, and Feher supercritical cycles. Thermodynamic property data on eighteen candidate working fluids for the Rankine and Feher supercritical power cycles have been assembled and were presented in a utilizable form. The thermal efficiency (ratio of the net work out to the heat input) and the many …

The Anodic Dissolution Of Molybdenum In Acidic Nitrate Solutions, Kuan-Hsiung Hoh

Masters Theses

"The anodic dissolution of molybdenum in 1.0 N HNO₃ (pH = 0.3) , 0.1 N HNO₃-0.9 N KNO₃ (pH = 1.2), and 0.01 N HNO₃ -0.99 N KNO₃ (pH = 2.1) was investigated. The following conclusions were possible: 1. Mo is in general electrochemically oxidized to the Mo-VI state during anodic dissolution. 2. The resultant ions in solution are HMOO⁻₄. 3. The Mo surface in aqueous solutions is covered with an oxide whose approximate composition is Mo₂O₅. 4. The polarization curves have a linear Tafel region at potentials slightly above the rest potential. 5. There is no significant effect of …

An Analysis Of A Synchronization Scheme For 180° Biphase Modulated Signals, James Joseph Spence

Masters Theses

"The problem of analyzing a synchronization system for demodulation of 180° biphase modulated signals is considered in this thesis. The system considered utilizes the so-called squaring loop technique. Techniques derived from the theory of Markov processes are utilized in the analysis of the system. In particular the "fluctuation equation" approach for non-Markovian processes is used. After the analysis of the system is performed, an expression fro the bit error probability is obtained from knowledge of the phase error density function"--Abstract, Page ii.

Measurement Of Thermal Accommodation Coefficients Of Steel Surfaces, Wing On Ho

Masters Theses

"The thermal accommodation coefficient plays an important role in low density thermal energy transfer measurement. The object of this investigation was to measure the thermal energy transfer between a heated test surface and a water cooled reference surface (flat black lacquer) consisting of two infinite concentric cylinders separated by dry air. Two machined and sanded steel cylinders with mean surface roughnesses of 25 microinches and 7.5 microinches were used as the test surfaces . Measurements were made in the pressure range of 1.2 x 10⁻⁶ mm Hg. to 1.8 x 10⁻⁶ mm Hg. and temperature range for test cylinders of …