Digital Commons Network^™

Dynamic Capacitance Of Metal-Oxide-Semiconductor Field-Effect Transistors, Marion Wendell Tucker

Masters Theses

"A transient peak was observed for MOSFET devices when measuring the dynamic capacitance versus applied gate voltage for various configurations at low frequencies. This peak is absent in conventional steady-state ac measurements. Since the peak is also absent in high grade devices and at high frequencies a possible explanation in terms of surface state traps is discussed for the observed phenomena"--Abstract, page ii.

Chemical Precipitation Of Phosphorous With Sodium Aluminate And Alum In The Activated Sludge Aeration Chamber, Richard Charles Vedder

Masters Theses

"The purpose of this investigation was to study the removal of phosphorus by chemical precipitation with sodium aluminate and alum in the activated sludge aeration chamber, and determine the effect of the aluminum to phosphorus ratio and the mixed liquor suspended solids concentration on the phosphorus removal efficiency and the effect of the precipitants on the removal of organic pollutants in the activated sludge process. The studies were conducted on settled domestic sewage in three bench-scale continuous flow activated sludge units supplemented with jar tests. Major parameters employed included influent and effluent total phosphorus and chemical oxygen demand (COD), mixed …

The N-Wire Exponential Transmission Line, Vernon Ray Stanley

Masters Theses

"This paper deals with the n-wire exponentially tapered transmission line. A characteristic impedance is defined, and the results of terminating in this impedance are investigated. A very long line and the condition of no reflections are considered, and the conclusions are compared. Finally, three specific 3-wire line problems are worked with a characteristic impedance termination and a unit step input"--Abstract, page ii.

Transient Response Of A Class Of Distributed Systems, Jaw-Shyong Tzeng

Masters Theses

"The transient response of uniform distributed systems with any transfer function that is rational in w=e[square root of Ts] can be analyzed with the basic form of the transfer function [1 over (w-a)] after partial fraction expansion, where the pole a can be real or complex in the w plane. with the complex pole within the stable region in the w plane, there are only two possible combinations of the basic transfer function [1 over (w-a)], i.e. [1 over (w-a)] ł [1 over (w-a*)], for physical realizability. The imaginary part of the transient response of the basic transfer function [1 …

A Simulation Of The Transistor By Computer Using The Linvill Diffusion Model, Clifford D. Skouby

Masters Theses

"This investigation involves the construction of an analog computer model of the transistor. The computer model is based upon the Linvill diffusion model. The equations for the Linvill diffusion model were programmed on the computer by making certain approximations. Different models, using different approximations, were used for the different regions of operation of the transistor. A composite analog model was constructed by combining the models for the restricted regions, giving a general model good for all regions of transistor operation. This analog diffusion model was modified to account for the effects of junction capacitance and base resistance. The modified analog …

The Analysis Of A Phase-Locked Loop By The Functional Expansion Method, Hugh Francis Spence

Masters Theses

"The time response of a generalized second order Phase-Locked Loop to step and ramp inputs is described by a functional power, truncated at the third order term. The responses given by the functional power series differs from the analog simulation by less than 6% when the inputs are below 2.0 rad (rad/sec)"--Abstract, page ii.

An Unsteady-State Method For Determining The Thermal Conductivity Of Materials, Richard H. Bulmer

Masters Theses

"Originally this work was initiated to develope [sic] a method for measuring the thermal diffusivity and thermal conductivity of metals. Due to the characteristics of the method and the equipment used, it was concluded that the technique is not suitable for materials of high conductivity. However, results show that the apparatus is valuable for the determination of the thermal diffusivity of relatively poor heat conductors. The favorable characteristics of the method are its rapidity and basic simplicity"--Abstract, page ii.

A Formal Description Of The Scc 650 Digital Computer, Hardy J. Pottinger

Masters Theses

"The requirements of a descriptive language for automated digital computer design are presented. Y. Chu's Computer Design Language is then used to describe the logic of the SCC 650, a small general-purpose digital computer at UMR. Chu's language is found to be the best language available to the designer for both documentation and automatic translation into Boolean Equations"--Abstract, page ii.

An Ultrasonic Pulse Generator Using The Transducer As A Frequency Determining Element, Donald E. Watke

Masters Theses

"This paper describes the development of a method of ultrasonic pulse generation in which the transducer determines the frequency of oscillation. A definite advantage of this method is the ability of the frequency of oscillation to change with changes in the transducer mechanical resonant frequency. This maintains peak efficiency at all times. The method is demonstrated in a small sonar transmitter but could be applied to any area involving driven ultrasonic transducers"--Abstract, page ii.

A Kinetic Investigation Of The Reaction Of Ethylenedinitrilotetraacetic Acid (Edta) And Cerium (Iv) In Acid Solution, Sahmia K. Al-Hashimi

Masters Theses

"The reaction between Ce(IV) salt solutions and EDTA solution was followed titrimetrically and spectrophotometrically and found to occur in stages. Four equivalents of Ce(IV) are reduced per mole of EDTA almost instantaneously at room temperature or even lower. With increasing temperature and reaction time an ultimate of about 14 equivalents of Ce(IV) is consumer per mole of EDTA. Formaldehyde, carbon dioxide, and other unidentified compounds are the products of oxidation of EDTA with Ce(IV). The kinetics of the reaction in aqueous sulfuric acid (0.09 - 2.95 M̲) was studied over the temperature range 11.7-40⁰ by a spectrophotometric technique. In the …

Kinetics Of The Formation Of Strontium Zirconate, W. H. Parker

Masters Theses

"The decomposition rate of strontium carbonate (SrC0₃) was measured using a TGA apparatus. It was found to deviate slightly from zero order classical reaction. The rate of formation of strontium zirconate (SrZr0₃) from zirconium oxide (ZrO₂) and strontium oxide (SrO) in the form of the decomposition product of SrCO₃ was measured using quantitative x-ray diffraction for mineralogical analysis. It was found to most nearly follow the Zhuravlev-Lesokhin-Tempel' man rate equation. The rate of decomposition of strontium carbonate was found to be more rapid than the rate of formation of strontium zirconate such that for the most part strontium oxide is …

The Downhole Suspension And Testing Of An Electrodynamic Shear Wave Exciter, Robert Franklin Kehrman

Masters Theses

"The work in this research project was aimed at designing a Downhole Electromagnetic Shear Wave Generator capable of delivering a wide frequency band, random, continuous signal. This Exciter was built using a compressed-air driven piston assembly for downhole application. The device was tested in the laboratory in a concrete test facility. It proved to be capable of transmitting a continuous, measurable stress into the concrete in a 100 to 5,000 hertz frequency band"--Abstract, page ii.

A Study Of Porous Membrane Evaporation For Desalination In A Flow System, Jing Ming Lee

Masters Theses

"The purpose of this investigation was to study the simultaneous mass and heat transfer mechanism in evaporation through a porous membrane with a non-wettable surface. Such water repellent membranes permit the passage of water vapor, but not liquid water. The investigation concerned the mass transfer rate through the membrane pores with flow on one or both sides of the membrane. The water-repellent membrane separated a hot salt solution from the fresh water, and a copper sheet separated the fresh water from a cold salt solution. A three-channel evaporator-condenser was used, and the membrane consisted of glass fiber paper treated with …

Investigation Of Thermal Resistance At The Interface Of Dissimilar And Similar Metals, Ching-Liang Lin

Masters Theses

"Experiments have been conducted to investigate the resistance and the effect of the directional heat flow at the interface of metals in contact. The test specimens were cylinders, axially aligned and dead weight loaded. Specimen materials were aluminum, bronze, and steel. The tests were conducted at environment pressures of 5x10⁻⁵ Torr. or less. The dead weight load was kept at 10 lbs. for all tests and the surface roughness for all specimens was from 6 to 8x10⁻⁶ inch. The results of the investigation reveal that the resistance to heat flow at the interface of metals decreases as the interface temperature …

Constant Horizontal Force Machining Through Flash Welded Steel Bars Of Varying Hardness, Donald Naeger

Masters Theses

"The purpose of this experiment was to determine the effect of a constant horizontal force applied to the carriage of a lathe as it turned a piece of stock which consisted of two steel bars, of different hardness, flash welded together. This experiment was performed on a lathe to which a pulley system with a mechanical advantage of six was attached to the carriage. The strain on the tool was measured both in the horizontal and vertical directions by a tool dynamometer on which eight strain gages were mounted. The strain gages were calibrated on a Tinius-Olsen testing machine. The …

An Intensity Regulation System For A Monochromator, David A. Wayne

Masters Theses

"In the investigation of phenomena involving both optical intensity and wavelength, an instrument is often desired which allows one of the quantities to be held constant while the other is varied. A relatively inexpensive system is described which utilizes a commercial grating monochromator and external feedback electronics to regulate the output intensity as the wavelength is varied. In this system, a sample of the output intensity is taken by a photosensor with known spectral response. The output of the photosensor is then compared electronically with that of a pre-programmed function generator which cancels nonlinearities in the photo-sensor. The resulting signal …

The Modeling, Fabrication, And Testing Of An Instantaneous Torque Measuring System, Thomas Phillip Hertel

Masters Theses

"The purpose of this work was to obtain a measuring system to experimentally determine the instantaneous magnitude and frequency of the torques from zero to 2400 Hertz produced by a single phase motor. This paper explains the methods employed in designing and fabricating a measuring system and shows the results from tests using this equipment. It was found that a measuring system based on the determination of the instantaneous value of the stator's reaction torques could be realized. Also, it was found that some simple methods of computation could be used to find the magnitudes of the frequency components comprising …

Lateral Variations Of Carbonate Rock Adjacent To Ore Deposits In The Upper Mississippi Valley Zinc-Lead District, Wisconsin, Illinois, Iowa, Mehdi H. Mirbaba

Masters Theses

"The lateral variation and nature of carbonate host rock in the Upper Mississippi Valley zinc-lead district were petrographically studied within the McGregor and Quimbys Mill Members of the Platteville Formation of the Middle Ordovician System. These members are dolomitic limestone in the Upper Mississippi Valley district of southwestern Wisconsin, northwestern Illinois and northeastern Iowa. One hundred and twenty-seven specimens were collected or were available from pull drifts in the Shullsburg mine. The specimens were collected at regular intervals of 50 or lOO feet in seven pull drifts between eight ore bodies. Thin sections prepared from the carbonate specimens were studied, …

Determination Of Molecular Diffusivities In Liquids, Pai-Chuan Wu

Masters Theses

"A porous plate, initially at a uniform solute concentration is immersed in a well-stirred pure solvent bath of known volume. It is desired to find the molecular diffusivity of the solute-solvent system by observing the change of the solute concentration in the solvent bath with time. In this study, concentration-time data were curve-fitted by non-linear, least squares techniques to the various mathematical solutions describing molecular diffusion in the porous frit. This technique is used to determine the diffusion coefficient and predict the value of other parameters existing in the different mathematical diffusion models. The results from the different models are …

Impulse Response Of Rc Exponential Lines, Oscar Gojon

Masters Theses

"This thesis presents an application of the analysis of the n-wire exponential line to the case of the 3-wire RC exponential line terminated in its characteristic impedance, and to the 2-wire exponential line with open and short circuit terminations. These lines are excited with Δ-function voltage generators, and the corresponding impulse responses are obtained"--Abstract, Page ii.

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 …

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 …

Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe

Doctoral Dissertations

"The circulating drop mass transport model based on Hadamard's dispersed phase stream function was solved numerically to account for a solute diffusing into a droplet and undergoing a first order irreversible reaction with the drop medium for the case where the continuous phase resistance to solute transport is negligible ... Experimental data were obtained for a system which consisted of 2-chloro-2-methylpropane (t-butyl chloride) diffusing from a benzene continuous phase into falling water droplets and undergoing a first order irreversible reaction with the water droplets ... The experimental solute transport rates were a factor of 7 to 10 greater than those …

Recombination Statistics For The Neutron-Induced Base Current Component, Ming-Chwan Chow

Doctoral Dissertations

"This paper presents a derivation of the recombination statistical model for the neutron-induced base current component. The derivation was based on the assumptions: 1) the current equation for the induced current component developed by Goben is valid; 2) the Shockley-Read-Hall statistics for holes and electrons are applicable; and 3) the recombination statistics derived by Sah, Noyce and Shockley, for sites in the bulk space-charge region are valid. Several examples were presented to emphasize accuracy of this derived model for predictions. This paper shows that the recombination process may be described by a mathematical model, recombination statistics which depend on the …

Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe

Doctoral Dissertations

"Surface self-diffusion coefficients have been measured by a radioactive tracer method over the temperature range 614⁰ to 840⁰C on nickel (111) surfaces characterized by LEED. Previously unrecognized tracer evaporation during surface diffusion resulted in restricted spreading of the tracer at higher temperatures. A theoretical treatment of the tracer evaporation phenomenon is presented and subsequently used in the analysis of the data. The temperature dependence of the surface self-diffusion coefficient (D_s) for nickel (111) can be represented, over the experimental temperature range, by a single Arrhenius type relationship...Arguments are presented to justify an adatom surface diffusion mechanism which is …

Design Of A Sequential Detector, Scott William Abel

Masters Theses

"The communication engineer has in the past treated the detection problem from a limited point of view. Detectors have been designed to reach a decision based on a specified number of samples. This approach has proved valuable, but it offers no provisions for an early decision if a conclusion becomes obvious early in the sampling. Neither is there an opportunity for additional sampling if necessary to reach a definite conclusion, because of these limitations it is desirable to find more general detectors. This study looks at a specific statistics (the sign test) and designs a sequential detector to utilize this …

Semiempirical Determination Of The Differential Fast Flux Spectrum For U-235 Fission With Water Moderator, Henry Anthony Till

Masters Theses

"The differential fast flux spectrum of the UMR Pool Research and Training Reactor core was determined by simultaneous activations of threshold foil detectors by neutron-nucleon reactions. This represents one phase of the composite neutron environment at two sample irradiation locations and the center of a fuel element during a power operation of 200 Kw (th). To accomplish this measurement a semiempirical least-squares approximation fitting activation date to a theoretical Cranberg U-wet fission spectrum was applied. This is a technique designed specifically for water moderated systems and takes into consideration both virgin and down-scatter neutrons. Gamma decay photopeaks were reduced using …

Shear Strength Behavior In Silts And Clay Mixtures, Alan T. Jackson

Masters Theses

"A series of consolidated undrained triaxial tests with pore pressure measurements were performed on laboratory sedimented samples having various known silt to clay content ratios. The clay used was commercial grundite clay from Goose Lake, Illinois, and the silt used was extracted from Lebanon Silt Loam from Rolla, Missouri. Silt was mixed with clay in the following percentages by weight: 0%, 20%, 40%, 50%, and 80%. Results indicate an increasing angle of internal friction with an increase in silt content. The unconfined compressive strength of the samples remained constant, as would be expected in a clay, with increasing silt content …

Pressure Welding Of Continuously Cast Nodular Iron, Gerald W. Wille

Masters Theses

"The objective of this study was to determine the feasibility of using pressure welding as a joining technique for swaged nodular iron.

Test pressure welds were produced with swaged continuous cast nodular iron at temperatures between 1750⁰F and 2050⁰F with welding pressures between 15,900 psi and 51,400 psi using an induction coil to heat the weld zone.

Pressure welds of greater strength than the as-received nodular iron were produced by swaging the material before welding. The optimum welding parameters were a temperature of 2050⁰F with a welding pressure of 46,700 psi.

On the basis of these tests it is concluded …

Synchronization Of Pulse Code Modulation Telemetry, Lawrence J. Mueller

Masters Theses

"Pulse Code Modulation (PCM) is one of the most widely utilized radio telemetry techniques for the recovery of test data from aerospace vehicles. Synchronization of the receiver with the transmitted data is perhaps the prime requisite of a PCM telemetry system. In this paper the frame synchronization process is analyzed by developing equations which define the three modes of synchronizer operation (SEARCH, VERIFY, and LOCK) in terms of the relative probabilities of operation. The criteria employed to optimize the synchronization process are the mean time to acquire true synchronization, the probability of true synchronization after verification of the synchronization decision, …