Digital Commons Network^™

Compressive Creep Of High Alumina Refractories, Vernon Lee Burdick

Masters Theses

"The deformation of refractory materials consisting of 90% sintered or fused alumina plus 10% silica was measured at temperatures from 1450 to 1515⁰C and a compressive stress of 100 psi. Creep rates and activation energies were determined from the steady state portion of deformation vs. time data and correlated with the mineralogical composition. Supplemental measurements included x-ray diffraction, electron probe microanalysis, apparent porosity and tensile strength. conditions having an important effect upon the mineralolgical composition were: (1) duration of heat treatment, (2) amount of sodium oxide impurity, and (3) reactivity of the alumina grain. Prolonged heat treatment and sodium oxide …

The Design Of A Drum Memory System, Frederick W. Lynch

Masters Theses

"Three methods for obtaining an auxiliary memory for an SCC-650 (Scientific Control Corporation) digital computer are presented. A logic design is then developed on the basis of using the drum and write circuits from an available IBM-650 digital computer and constructing the remaining logic functions. The results of the logic design are the transfer equations necessary to implement the memory system"--Abstract, page ii.

An X-Ray Study Of The Lead Titanate-Bismuth Chromate System, Tsen-Tsou Shih

Masters Theses

"The lead titanate-bismuth chromate system was studied employing x-ray diffraction techniques at both room and high temperatures. Samples were prepared by sintering stoichiometric mixtures of the corresponding oxides followed by air quenching. Bismuth chromate was prepared by resintering and air quenching for four times. The results of the analyses show the structure of BiCrO₃ to be tetragonal with 8 molecules per unit cell. Solid solutions exist over the range 100 to 35 mole percent PbTiO₃ of the binary system, although small amounts of other phases are present in some regions. X-ray data at room temperature indicate the tetragonal perovskite structure …

A Study Of The Molecular Emission And Of The Life Times Of The Metastable States In The Afterglow Spectrum Of A Mercury Discharge, Bruce M. Whitcomb

Masters Theses

"Two methods of studying the spectrum in the early afterglow of a pure mercury sample are discussed. Using a time-sampling technique, information about the intensity of the spectrum as a function of time in the afterglow can be obtained. The intensities of two molecular bands, centered at 3350A and 4850A, are studied. The method of formation of the diatomic mercury molecule and the emission of radiation in the two bands are shown to be density dependent. Mechanisms are presented which explain both the molecular formation and the radiation in the two bands. In an absorption study, the half-lives of the …

A Kinetic Study Of Ti⁺³ Oxidation To Ti⁺⁴ In Hydrofluoric Acid Solutions, Kuo-Shein Shen

Masters Theses

"The purpose of this investigation was to study the oxidation rate of Ti⁺³ to Ti⁺⁴ in hydrofluoric acid solutions in the absence of air. The concentration of hydrofluoric acid was varied from 0.25 to 2.00 M and the concentration of titanium from 0.05 to 0.50 M. The temperature was controlled at 25⁰C. The reaction rate was relatively slow. In most instances, less than 50 percent of the Ti⁺³ was oxidized during a period of 100 hours"--Abstract, page vii.

Digital Filter Design And Evaluation, David Alvarado MaguiñA

Masters Theses

"This thesis is concerned with the application of two digital filter design techniques to the Pade approximate continuous filters. The (m, n) Pade approximant has a numerator polynomial of degree n in s and a denominator of degree n in s. The (n-1, n) approximates are desirable for linear phase low pass filters, pulse delay circuits without initial condition errors, and pulse forming networks. A collection of plots is shown to demonstrate the quality of the approximations in the frequency domain, as far as amplitude and phase are concerned. These low pass approximants are normalized to a cut-off frequency of …

Stress Analysis Of A Wall Footing Subjected To External Vertical Loads And Overturning Moments By The Finite Element Method, Adil Godiwalla

Masters Theses

"This investigation pertains to the stress analysis by the finite element method of a wall footing subjected to external vertical loads and external overturning moments. This problem has been reduced to a two-dimensional stress analysis problem by taking a unit length of the wall. A rectangular plate - element is used throughout this investigation. The development of the matrix equations is shown and the solution is performed by digital computer. Stresses in the horizontal direction show essentially linear variation which is in agreement with simple structural theory, while stresses in the vertical direction show severe perturbation near the column load. …

Mode Analysis Of The Unsymmetrically Fed Ground-Plane Aperture, John G. Hemmann

Masters Theses

"The problem of radiation from a waveguide-fed ground-plane aperture perturbed with a wedge-shaped dielectric insert was examined more carefully. The work initiated by Blumberg was continued, using a greater range of dielectric constants and smaller increments of angle.

Aperture field measurements were made over a range of dielectric constants for each wedge angle, in order to determine the change in amplitude distribution as a function of permittivity. Aperture phase measurements were also taken for selected angles. These were used with the amplitude data to predict, using numerical integration, the far-field radiation patterns of the perturbed aperture. Far-field patterns were then …

Vapor Pressure And Evaporation Coefficient Of Cadmium Oxide, R. Tom Coyle Jr.

Masters Theses

"Knudsen effusion experiments were carried out on CdO in fused silica crucibles at temperatures of 918°K, 1008°K with orifice areas from 2.742x10^-3 cm² to 30.52x10^-2 cm². The experiments were made in a molybdenum-wire, resistance-heated vacuum furnace. Several orifice areas were used at each temperature and reciprocal pressure versus orifice area plots were made. These plots yielded an upper limit to the evaporation coefficient of. 4.15x10^-2. An equilibrium constant for the vaporization reaction

CdO(s) = Cd(g) + 1/20₂ (g)

of

log Keq = 11.12 - 1.952x10⁴/T.

was obtained. Second and third …

Molecular Diffusion In Polymer Solutions By A Microinterferometric Method, Surendra V. Desai

Masters Theses

"The object of this investigation of molecular diffusion in aqueous polymer solutions was to study the effect of solute concentration on the differential diffusion coefficient and also to study the effect of polymer concentration on the mean integral diffusion coefficient. For this purpose a microinterferometric method was used. Two non-ionic, water soluble polymers, Carboxymethylcellulose (CMC) and Carboxypolymethylene (Carbopol), were used in the study with D-Glucose as a solute.

The differential diffusion coefficient was found to increase with increases in solute concentration in all cases. For CMC, the integral diffusion coefficient at first decreased with increasing polymer concentration but became constant …

An Investigation Of The Reaction Of Benzhydryl Chloride With Potassium T-Butoxide In Dmso, Lawson Gibson Wideman

Masters Theses

"The ultimate aim of this study was to elucidate the mechanism of formation of tetraphenylethylene from benzhydryl chloride and potassium t-butoxide in dimethyl sulfoxide. The development of a suitable technique for following the reaction rate and of an analytical method to determine the extent of the reaction became an important object in this project"--Introduction, page 2.

Analysis Of Trace Elements In River And Spring Waters, Faridoon Andeshire Namdarian

Masters Theses

"Methods for the analysis of trace elements in natural fresh waters were investigated.

Preconcentration of the water samples by reducing the volume and by using cation adsorption resins was studied. It was concluded that cation absorption was the more promising procedure.

The methods used for analysis were absorption spectrophotometry, neutron activation analysis, and atomic absorption spectrophotometry. Atomic absorption spectrophotometry was considered the most suitable method for the analysis of trace elements in waters.

Calcium, copper, lead, zinc, and cadmium were determined in a number of Missouri springs and stream water samples"--Abstract, page ii.

The Realization And Application Of Parallel Linear Feedback Shift Registers, Ross K. Heitzmann

Masters Theses

"Two methods for serial-to-parallel transformation of linear feedback shift registers are briefly discussed. A third method for transformation is rigorously developed using a next-state and output equation representation of the linear feedback shift register. An algorithm is developed for simplifying the parallel machine resulting from serial-to-parallel transformation, where simplification is defined as reduction in the required number of modulo 2 adders. A computer program incorporating serial-to-parallel transformation and the simplification algorithm is provided "--Abstract, page ii.

Infrared Spectra And Magnetic Properties Of Fluorine Substituted Copper (Ii) Alkanoates, Jose G. Rodriguez

Masters Theses

"The purpose of this study was to prepare some selected copper(II) fluorcalkanoates, investigate their magnetic susceptibilities, study the infrared spectra of these salts and compare these properties to those of the unfluorinated copper(II) alkanoates….

The experimental data obtained indicate that the copper(II) trifluoroacetate, perfluoropropanoate and perfluorosuccinate does not form a binuclear cage structure. Copper(II) 3-(trifluoromethyl) butanoate with a magnetic moment of 1.4 should possess a binuclear case structure similar to copper( II) acetate monohydrate. The structure for copper( II) perfluoroglutarate monohydrate with a magnetic moment of 1.63 B.M. should have a structure somewhere between the two aforementioned structures"--Abstract, page ii.

Characteristic Impedance Of Open Microstrip Transmission Lines Having Finite Thickness And Multiple Dielectric, Philip Julian Carter

Masters Theses

"A computer program is provided for determining the characteristic impedance of microstrip transmission lines having finite thickness. Infinite and finite ground planes are incorporated into the program. The programmer need only supply information in the form of a data card. This procedure is clearly outlined.

Graphical solutions of characteristic impedance for multiple dielectric microstrip transmission line problems are obtained using a discrete resistive analogue. Computer network analysis programs are viewed as having several advantages not possessed by the physical resistive analogue"--Abstract, page 2.

A Petrofabric Study Of The Iron Ore Of Benson Mines, Star Lake, New York, Remo Antonio Masiello

Masters Theses

"The petrofabrics of the host gneiss silicates and Ovate ore grains were studied in thin sections of oriented specimens collected from widely scattered positions in the iron ore deposit at Benson Mines, New York.

Ten oriented specimens selected for petrofabrics study were comprised primarily of feldspar, quartz, garnet and ores, with lesser quantities of biotite and sillimanite. Petrofabric diagrams were prepared for the orientation fabrics of magnetite and biotite in eight of the ten specimens, but sillimanite and quartz were sufficiently abundant for fabric determination in only three specimens. Duplicate thin section and perpendicular sections were utilized to check the …

A Comparison Of Friction And Drum Hoisting Systems On An Energy-Input Basis, Hemendra Nath Kalia

Masters Theses

"The purpose of this thesis is to provide a suitable basis for comparing the relative advantages of the friction and drum hoists under various conditions of operation.

Such comparisons are mainly and necessarily based upon physical characteristics of the mechanisms for lack of appropriate economic data. It is believed, however, that this inadequacy may be alleviated to some extent by substituting comparative theoretical energy requirements of' the two hoisting systems under identical duty conditions over a practical range of mining situations involving various depths and daily productions.

This has been accomplished by adapting a computer to standard mine-hoist design techniques …

Anodic Dissolution Of Zinc In Potassium Nitrate, Martin E. Straumanis, J. L. Reed, William Joseph James

Materials Science and Engineering Faculty Research & Creative Works

The apparent valence of pure zinc dissolving anodically in 3% KNO₃ was determined as a function of current density, temperature, and ultrasonic agitation. The apparent valence of zinc dissolving anodically at 24°C diminishes from 2.01 ± 0.01 at low current densities to 1.86 at about 50 ma and remains fairly constant up to about 80 ma cm−2. This valence is affected to some extent by the preparation, e.g., polishing of the electrode, but is independent of its structure (mono- or polycrystal). Ultrasonic vibrations do not influence the apparent valence at high current densities. In all cases a black film …

Thermal Expansion Coefficients And Lattice Parameters Between 10° And 65°C In The System Gap-Gaas, Martin E. Straumanis, J. P. Krumme, M. Rubenstein

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

A Plastic Stress Analysis Of Cylindrical Wafers Under Elastically Deformable Compression Plates, Robert L. Davis, J. W. Jackson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper represents an analysis of the pressure distribution occurring in axially loaded cylindrical wafers with, and without, elastic radial constraints. The purpose of this report is to demonstrate the resulting stress patterns that occur in short compression specimens frequently used in determining material properties, and in the opposed-anvil, or Bridgman-type, high-pressure cells. The influence of radial constraints, material strain hardening, wafer diameter-to-height ratio, anvil or plate deflection, and the wafer-anvil interface friction on the resulting stress distributions have been examined. The integrated normal stress distribution across the specimen surface has been verified experimentally via numerous tests in which each …

Dynamic Response Of Plates Due To Moving Loads, Theodore F. Raske, Alois L. Schlack

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An analysis based on linear theory is presented for determining the dynamic response and the conditions of resonance for a simply supported rectangular plate acted upon by two types of moving loads corresponding to: (1) a point force of variable magnitude oscillating about a fixed position on the plate, and (2) a point force of constant magnitude traveling in a circular orbit about a fixed position on the plate. In addition to the ordinary resonance as produced by a variable magnitude load concentrated at a fixed position on the plate, resonance of the plate may occur due to the changing …

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 …

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 …

The Amino Acid And Monosaccharide Content Of The Cell Walls Of Thiobacillus Thiooxidans, Edward Hibbert Crum

Doctoral Dissertations

"The objectives of this investigation were: (a) to culture large quantities of Thiobacillus thiooxidans cells, (b) to find an acceptable method of rupturing the cells, (c) to find an acceptable method of isolating the cell walls, and (d) to analyze the cell wall components, especially the amino acid and sugar components. The strain of T. thiooxidans used for this investigation was American Type Culture Collection Number 8085. The surface active agents Tergitol 08 and Tween 80 were investigated for their ability to reduce the lag period found in the growth of T. thiooxidans. Although a concentration of 12.5 ppm Tween …

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 …

A Study Of Surface And Geometric Effects On The Nucleate Boiling Of Liquid Nitrogen And Liquid Argon From Atmospheric To The Critical Pressure, Calvin Benson Cobb

Doctoral Dissertations

"A maximum heat flux correlation was derived for corresponding states liquids and subsequently verified by the data collected in this study as well as data presented in the literature. By applying this correlation, one can predict maximum heat flux values at high pressures from maximum heat flux values measured at low pressures; however, to apply the correlation it is necessary to have at least one maximum heat flux value and the saturation temperature at which it was determined.

Contrary to existing correlations, it is shown that for any nucleate boiling heat transfer correlation to be truly general, it must include …

Design Of A Nonparametric Detector For Fm Signals, James Charles Fowler

Masters Theses

"The communication engineer has in the past treated the detection problem from a parametric point of view. That is, the signal has been assumed to be of a known deterministic form and the noise of a known statistical form. This approach has proved valuable in many cases, but it is subject to severe limitations, e.g., if either the noise or signal change form, a new detector must be designed. Because of these limitations there is a need to find a more general form of detector.

This study looks at a specific statistic (the Cramér-von Mises statistic) and designs a detector …

The Acidic Transformaion Products Of Indoles Formed By Basidiomycetes, Chung-Ke Chang

Masters Theses

"A survey of the ability of basidiomycetes to convert tryptophan, tryptamine and indole acetic acid to other acidic indoles has been made.

The product formed from tryptamine by Tricholoma nudum was identified as indole acetic acid. The product formed by Cantharellus cibarius from D-tryptophan was identified as N-acetyl-D-tryptophan. The products were purified and identified by means of paper chromatography, thin layer chromatography, infrared spectroscopy and melting points.

The conversion of tryptamine and D-tryptophan was also studied in cultures of Leucopaxillus paradoxus, Hygrophorus conicus and Naucoria confragosa. H. conicus, L. paradoxus and N. confragosa transformed tryptamine and indole acetic acid into …

Gap-Graded Gravel For Asphaltic Paving Mixtures, Ernest Harrington Martin

Masters Theses

"The objective of this investigation was to determine if naturally occurring gap-graded gravel can produce asphaltic mixtures meeting minimum requirements for satisfactory pavement behavior.

Ten gap-graded mixes were blended by eliminating certain intermediate sized fractions or combination of fractions from the gradation of a control mix. The weight of the fractions eliminated was distributed to either the coarser or finer aggregate fractions.

All specimens were prepared and tested in strict accordance with procedures set forth in ASTM Designation D1559, "Resistance to Plastic Flow of Bituminous Mixtures Using Marshall Apparatus."

The physical properties compared and analyzed were (1) unit weight, (2) …

A Study Of Probability Of Error Calculations For Baseband Multi-Level Digital Transmission Systems Using The Fixed Threshold Decision Rule, Don J. Popp

Masters Theses

"This study is an investigation into analytical techniques used in deriving probability of error expressions for baseband multi-level digital transmission systems. A fixed-level decision rule is used to solve this statistical detection problem together with some simple concepts from probability theory. To illustrate these techniques, probability of error expressions are derived for the general uncoded system, a simple coded system, and a complex coded system. Curves of probability of error versus signal-to-noise ratio are plotted for the various systems considered"--Abstract, page ii.