Digital Commons Network^™

Construction Of A Laboratory Type, Convertible Excitation Argon Laser, Arthur P. Reckinger

Masters Theses

"The purpose of this thesis is to describe the construction of a general purpose, convertable [sic] excitation, laboratory type, argon laser. Quartz tubing was used in the final model while attempts to use alumina were made during earlier work. The final model has total optical power output of 230 mw at a discharge current of 29 amperes in the dc excitation mode. Provision was also made to utilize RF or pulsed excitation. The device is built so that several values of optical transmittance are available with a wide range of mirror placement"--Abstract, page ii.

Effects Of Mixing Procedure Upon Uniformity Of Fibre Reinforced Concrete, Donald E. Nortrup

Masters Theses

"This thesis describes the effects of several methods of introducing wire fibres into a concrete mix upon the uniformity of wire fibre reinforced concrete. Various mechanical and manual methods of introducing the fibres were used and comparisons of the methods were based upon variability in splitting tensile strength and the quantitative distribution of the fibres as determined by visual inspection of sawed cylinders. Test results show that the tensile strength of concrete is increased appreciably by the inclusion of steel wire fibres in the mix and the uniformity of strength is similar to that of unreinforced concrete. The methods of …

Continuous Countercurrent Evaporation Through Porous Water-Repellent Membrane With Pressure Above Atmospheric, Yung C. Hsu

Masters Theses

"An experimental method for measuring mass transfer rates at pressures above atmospheric has been developed for the case of continuous countercurrent evaporation through porous water-repellent membranes. The final developed equipment is suitable for operation under pressures up to 50 psig and at temperatures near the boiling point of 7% salt water when high flow rates are reached. Rates of evaporation of water through the membrane were measured, and the data and results were used to examine the effects of operating conditions on the over-all mass transfer resistance. Least squares equations for fitting the data were also obtained. Over-all mass transfer …

A Programmed Synthesis Procedure For Asynchronous Sequential Circuits, Robert Judson Smith

Masters Theses

"The synthesis procedure for large asynchronous normal fundamental-mode sequential circuits is time-consuming and tedious when performed manually. This paper describes a series of computer programs which, given a machine specification in flow table form, automatically produces simplified normal form implementation design equations. The user may specify that either minimum-variable state assignments, or more rapidly generated near-minimum-variable codes be found. Next-state equations are formed using the generated state assignments and converted to simplified sums of products. Sample machines having flow tables of up to eighteen rows by four columns are synthesized"--Abstract, page ii.

A Transmission Electron Microscopy Study Of Some High Strength Plain Carbon Steels, George Joseph Vytanovych

Masters Theses

"Methods of preparing foils of high strength, heat treated, plain carbon steels for examination in the electron microscope by the transmission technique were perfected and are described. Two processes for the initial thinning of a bulk sample were successful. A chemical process was found to be more rapid but not satisfactory for small samples. A mechanical process was slower, but was applicable to the smaller specimens. Electro-polishing the thinned material yielded acceptable foils from which photomicrographs of good quality were obtained. The microstructure of the high strength steel samples showed typical tempered martensite. No reasons for the differences in ductility …

The Effect Of Concentration On The Viscosity Of Dilute And Moderately Concentrated Polymer Solutions, Hwa Luh

Masters Theses

"The effect of concentration on the viscosity of dilute and moderately concentrated polymer solutions was studied for eight narrow molecular weight polystyrene samples (900

Annealing Characteristics Of Neutron Irradiated Silicon Transistors, Joseph Robert Chott

Masters Theses

"When a transistor is subjected to neutron irradiation, a component of base current proportional to neutron fluence is induced. From the effects of annealing on the base and collector currents, the conclusion was drawn that there is an apparent difference in the annealing characteristics between the neutral and the space-charge regions of the semiconductor device. This study of the anomalous annealing indicates that the neutron-induced component of base current is a result of one, or a combination, of the following mechanisms: a quasi-tunneling recombination phenomena in the emitter-base space-charge region, or an influence of the p-n junction electric field on …

Lattice Constants, Thermal Expansion Coefficients, Densities, And Imperfections In Gold And The Alpha-Phase Of The Gold-Indium System, Vinayak Keshavlal Patel

Masters Theses

"An investigation of structure insensitive properties (lattice parameters, thermal expansion coefficients, densities, and imperfection) of gold and the alpha-phase of the gold-indium system was made. The gold-indium alloys were prepared from high purity (99.999%) gold and indium by melting both metals inside sealed quartz glass tubes which were first evacuated and then filled with helium gas. The solidified alloys were annealed and then examined by x-ray for homogeneity. The lattice constant of 99.999% pure gold at 25⁰C was found to be 4.07894 ł 0.00005 (corrected for refraction) Å. The coefficient of thermal expansion was 13.4 x 10⁻⁶⁰C⁻¹ between 15 and …

An Investigation Of The Effects Of An Impact On Some Of The Mechanical Properties Of Aluminum Alloy 2014-T6, Rajnikant K. Shah

Masters Theses

"Static and impact tests were conducted on an Aluminum alloy 2014-T6 specimen. The purpose of this research was to determine the effects of an impact load on some of the mechanical properties of aluminum. The cross section of the specimen measured 4.438 in. by 3.850 in. and it was 12 in. long. It was equipped with a total of four electric resistance gages connected in two pairs. One pair measured longitudinal strain while the other measured transverse strain. Both gages in each pair were mounted on the opposite sides to cancel the bending effect. In the static tests, load was …

Analog Simulation Of A Plug Flow Tubular Reactor, Jon Douglas Carson

Masters Theses

"This thesis stresses the importance of analog and digital computers in the field of reaction kinetics. The analog computer is used to simulate a chemical reaction, the hydrolysis of acetic anhydride. The hydrolysis reaction takes place in a tubular reactor. The reactor is 3/4 inch in diameter and 20 feet long. These reactor dimensions allow the reaction system to approach plug flow, if the reactants flow through the reactor at turbulent flow rates. The physical, reactor, system is used to obtain experimental data for the hydrolysis reaction. The data is obtained at reactor temperatures between 75 and 100°F. Feed concentrations …

The Economics And Design Of Desalination By Evaporation Through Porous, Water-Repellent Membranes, Kuei-Hsiung Yang

Masters Theses

"The economics of desalination by evaporation through porous, water-repellent membranes has been studied in this investigation. Using reasonable assumptions this desalination process was found to be economical with the principal advantage being the simplification of multi-stage flash-type evaporation. Based on this process, two different methods were designed and studied by means of computer calculations for a 10 million gallons product water per stream day desalting plant. One method was based on a membrane evaporator and a heat exchanger and was designated Method I; and a combined evaporation-heat exchanger system was designated at Method II. The major factors affecting the economics …

Programmed State Assignment Algorithms For Asynchronous Sequential Machines., Wayne L. Schoeffel

Masters Theses

"An important step in the synthesis procedure for realizing a normal fundamental mode asynchronous sequential circuit is the internal state assignment. Although systematic methods have been developed to construct minimum-transition-time state assignments, they become long and tedious with hand methods for machines with more than 7 or 8 internal states. To extend the application of these algorithms to larger problems, this paper presents an efficient digital computer program for generating minimum-variable state assignments. An alternate program is also presented which, though shorter, does not guarantee a minimum-variable assignment"--Abstract, page ii.

The Relation Of Heat Transfer To Mass Transfer In Vaporization Through Porous Membranes., Chung-Liang Yeh

Masters Theses

"The object of this investigation was to study the mass and heat transport phenomena through porous, water-repellent membranes. The investigation concerned the rate of vaporization of salt water at a porous membrane surface, mass transfer of vapor through the pores of the membrane, condensation of vapor on the other surface of the membrane in contact with a coolant (fresh water), and the undesired heat transfer by conduction through the membrane. The water-repellent membrane separated the two liquid phases by surface tension forces and provided a vapor phase in its pores. Membranes made of fiberglass and Teflon had been found suitable …

Negative Resistance In Cadmium Sulfide., John William Mohr

Masters Theses

"A light-sensitive, negative-resistance phenomenon has been observed in a special two-terminal CdS device fabricated from selected single crystals. The device differs from those used in previous investigations in that one end of the device was masked to keep out visible light and that the phenomenon was observed at room temperature. A method is described which enables the phenomenon to be observed on a reproducible basis. It was found that the CdS single crystal must have a relatively high density of traps. Possible mechanisms which may contribute to the phenomenon are discussed"--Abstract, page ii.

Film Boiling From Horizontal Plates With Low Thermal Capacity, K. M. Ragsdell

Masters Theses

"The object of this investigation was to obtain data for saturated film pool boiling from a low thermal capacity flat plate at atmospheric pressure. A test plate, constructed from resistance strip, was placed horizontally in a pool of liquid, and was heated electrically. Refrigerant-11 and nitrogen were used as the boiling liquids. Heat transfer results were obtained in both fluids over a temperature range of approximately 1200F⁰ (400-1600⁰F). Surface size, roughness and orientation effects were observed for flat horizontal heated surfaces with one dimension near the most dangerous wavelength. No surface material effect was observed. Excellent correlation of the data …

Shutdown Reactivity Worth Of Reactor Control Rods By A Subcritical Multiplication Method, Leslie Roger Conner

Masters Theses

"Two modified subcritical multiplication methods for measuring the reactivity worth of control elements were developed and investigated. The first involved the calibration of a subcritical count interval by the asymptotic period method. The second involved the calibration of a subcritical count interval by a rod interchange with the reactor regulating rod which had previously been calibrated by the asymptotic period method. The accuracy of these methods is relatively poor. this inaccuracy is due to shadowing effects and to the spatial harmonics which exist in the core. An investigation of the spatial harmonics to determine the best location for the neutron …

Mass Transfer From A Torus Shaped Body, Kamalesh Suryakant Desai

Masters Theses

"A mathematical model for molecular diffusion in a torus was derived. Handlos and Baron have assumed a system of tori in their eddy diffusion model for liquid-liquid extraction from droplets. However, the effect of torus curvature was neglected in their studies. Since they assumed the torus could be represented by an infinite cylinder. In this study, the effect of torus curvature was considered on the concentration profile and the fraction of the solute extracted. The partial differential equation describing the model consists of three independent variables, and a finite difference technique was employed for the solution of the mathematical model. …

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.

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 …

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.

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 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 …

The Role Of Mortar Aggregate In The Strength Of Concrete : Technical Paper, Charles F. Scholer

JTRP Technical Reports

No abstract provided.

Automatic Technique For Abstracting Color Descriptions From Aerial Photography : Technical Paper, J. Gourley, Harold Teddy Rib, Robert Douglas Miles

JTRP Technical Reports

No abstract provided.