Digital Commons Network^™

A Study Of The Photomechanical Effect In Silicon, Ronald M. Oglesbee

Masters Theses

"This paper presents the results of an experimental investigation into the photomechanical effect in silicon. The effect was found to be very similar to the electromechanical effect. In both cases the phenomena observed is the softening of a thin surface layer of the material when it is either illuminated or when a current is flowing through the material. An anisotropy was observed in both the hardness and the photomechanical effect. Increasing temperatures tended to "washout" the photomechanical effect. The surface hardness and the photomechanical effect were found to depend heavily on proper surface preparation of the samples, however little dependence …

Effect Of Single Stirrups On Reinforced Concrete Beams, Vinodbhai T. Patel

Masters Theses

"This study was made to determine the location of vertical stirrups and also to determine the amount of stirrup-steel required to prevent diagonal cracking. The study is limited to rectangular, simply supported, reinforced concrete beams subjected to a concentrated point load at the center of the span. Five sets, each containing three beams were tested. Two sets were cast without stirrups and the results were used to locate the stirrups for the remaining tests. The other three sets were cast with one stirrup on either side of the central load. Stirrups were of the "U" type and formed form No. …

The Design And Construction Of An Instrument For Calibrating Accelerometers, Richard Rabenau

Masters Theses

"The purpose of this work was to design and construct a facility to calibrate accelerometers. A ceramic piezoelectric shaker and modified Michelson interferometer together with necessary electronic equipment were used. The system produced accurate and stable acceleration at five discrete points from 1,000 to 5,000 cycles per second. the maximum calibration levels were approximately 50 g's"--Abstract, page ii.

A Circularly Polarized Corner Reflector Antenna, Walter Ronald Koenig

Masters Theses

"Image theory is used to develop the far field and polarization equations for a ninety degree corner reflector antenna. These equations are in terms of spherical coordinates, the length of the dipole element, the distance of the dipole from the corner of the reflector, and the angle of tilt of the dipole element with the apex of the corner. The equations are simplified to give the far fields in the vertical and horizontal planes for the special case of a half-wavelength dipole. An expression to calculate the distance of the dipole from the corner necessary to give circular polarization broadside …

Radial Water Encroachment - An Approximation, Tommie C. Wilson

Masters Theses

"This presentation consists of the application of empirical equations for the calculation of the water influx into a radial oil reservoir in which the history of the rate and cumulative water influx are equated to the pressure decrements and time. This new analysis, based on William Hurst's solution for the steady-state water influx, yields an accurate method for determining water influx through the application of simple linear empirical equations. These linear approximations reproduce the rigorous influx solutions to a maximum deviation of 1.6 per cent"--Abstract, page ii.

Stability Determination By Liapunov's Method In Nonlinear Control Systems, Neng-Chung Liao

Masters Theses

"An introduction to Liapunov's second method as it applies to control system stability is presented in this work. Main theorems and definitions of Liapunov's method are treated. In particular, Lur'e's method and Szego's method for testing the stability of a nonlinear system are presented, and several examples are used to illustrate these procedures"--Abstract, page ii.

Use Of Spent Sulphite Liquor For Stabilization Of Fractured Rock And Sealing Off Water Bearing Formations, Laxman Singh Sunda

Masters Theses

"The paper industry, in its process of manufacturing pulp from wood, produces large quantities of a substance called lignin, lignin sulphite, or lignosulphonate. This material has been disposed of as a waste product; however, it does have many potential uses. In this investigation, lignosulfonates were used as agents for bonding rock sections together and, as the chief component of gels, for filling the pores of artificial rock cores. The purposes of these tests were to find how this substance could be used in the mining industry, for stabilizing fractured ground around mine openings and for sealing off water influx into …

Effect Of Calcium Lignosulfonate On Properties Of Concrete At Early Ages, Lawrence Kong-Pu Wang

Masters Theses

"The objective of this investigation was to determine the effects of calcium lignosulfonate on the physical properties of concrete. Calcium lignosulfonate used as an admixture was tested for its effect on the tensile and compressive strength of plain concrete cylinders, and for its effect on the flexural strength of plain concrete beams. The effect of the admixture on shrinkage, slump, air content and unit weight was also studied. the test results showed that calcium lignosulfonate reduces the amount of water required to make a workable concrete mix; a more workable mix saves money because it is easier to place, thus …

Solid Solubility Of Sulfur, Selenium, And Tellurium In Molybdenum At 1100°C, Lattice Constants Thermal Expansion Coefficients, And Densities Of Molybdenum And The Molybdenum-Base Alloys, Ramesh Purushottamdas Shodhan

Masters Theses

"With the ever increasing requirement for engineering materials having adequate mechanical properties at ever higher temperatures there has been, in quite recent years, a considerable increase in the study of molybdenum and molybdenum-rich alloys. Since 1945 extensive information on the engineering properties of molybdenum and molybdenum-base alloys has gradually become more available ... The present work involves the determination of solid solubility of elements with large atoms such as sulfur, selenium, and tellurium in molybdenum at 1100°C using the parametric method. Furthermore, the thermal expansion coefficients of pure molybdenum and of molybdenum-base solid solutions containing the elements just mentioned were …

The Effect Of Nickel On Activated Sludge, James Robert Matthews

Masters Theses

"The primary objective of this investigation was to determine the effect of nickel on activated sludge over a comprehensive range of concentrations and to evaluate the ability of the sludge to acclimate and become more tolerant to the metal. Six one-liter fill and draw activated sludge units were fed domestic sewage; five of these units also received constant, increasing, and shock doses of nickel while the sixth was maintained as a control. Treatment efficiency was evaluated in terms of the chemical oxygen demand, suspended solids, and nickel content of the effluent. A Warburg respirometer was also employed and was operated …

Detection Of Stress Corrosion Cracking In U-Bend Brass Specimens By An Electro-Mechanical Method, Floyd Elwin Loftin

Masters Theses

"An apparatus was designed and built which held two u-bend specimens. When the specimens were exposed to a corrodent, losses in strength were detected as a result of stress corrosion cracking. The apparatus was used to study time to failure of cartridge brass u-bend specimens exposed to ammoniacal copper sulfate solutions which varied in pH. A minimum time to failure, 1.06 hours, was detected at pH 7.2. The maximum time to failure, for the range studied, was 28.36 hours at pH 7.7.

No useful data were obtained in the range from pH 6.6 - 6.8. thick, black surface coatings were …

The Effect Of Cadmium On Anaerobic Digestion, Lyle Lynn Pruitt

Masters Theses

"The main purpose of this study was to determine the effect of cadmium on anaerobic digestion. Metal concentrations in the form of regular and slug doses were considered. The possibility of acclimating anaerobic bacteria to higher cadmium levels was studied, and attempts were made to reestablish digestive action through re-seeding in digesters overcome by high cadmium concentrations"--Abstract, page [ii].

Thin Film Resistor Deposition, Rollie R. Herzog

Masters Theses

"Thin film techniques may be the key to future miniaturization of electrical equipment. The purpose of this thesis was to develop procedures for deposition of thin film resistors and to test these deposited resistors. Starting with a vacuum system, equipment was designed and built to hold and heat the substrate, monitor the substrate temperature and deposited resistance, and to evaporate the material to be deposited. Resistors were deposited and tested for resistance between resistors, capacitance between resistors, and resistance of resistors. A heat aging test was also used comparing resistors with and without a silicon monoxide coating"--Abstract, page ii.

The Design Of A Sensitive Probe For Mass Flux Measurements Of Water Vapor In Air, Devendra Vaikunthlal Mehta

Masters Theses

"This investigation pertains to the construction and investigation of a sensitive probe to determine the possibility of measuring the mass flux of water vapor in air under non-flow steady state conditions. The probe was a small electrolysis cell is which the electrolyte (partially hydrated phosphorus pentoxide) was used as the sensing element. The rate of mass transfer was determined by measuring the amount of direct current flowing through the acid film"--Abstract, page i.

The Anodic Dissolution Of Cadmium In Nitrate Solution, Eh Deng

Masters Theses

"It is only relatively recently that the immensity of the problem of corrosion prevention has begun to be realized. In times when materials were plentiful, the problem did not seem so pressing. Now that a finite limit can be seen for the world*s resources of metals, and the cost of finding, mining and extracting them has become ever more expensive, the problem of controlling the destructive processes of corrosion has become an urgent one.

The basic mechanism of the anodic dissolution of metals such as cadmium, zinc, silver and magnesium in salt solutions is not completely known. Although several mechanisms …

The Microbial Hydrolysis Of Cellulose And Some Factors Affecting The Production Of Cellulase In A Submerged Culture Of Alternaria Sp, Robert Murray Logan

Doctoral Dissertations

"A mile hydrolyzing procedure was utilized to degrade oak sawdust. Its capability of producing a suitable fermentatation [sic] medium was studied. In the interest of solubilizing, enzymatically, the carbohydrate portion of oak sawdust, an investigation was conducted in which various microorganisms were examined for their ability to utilize different forms of cellulose for their growth and to produce cellulose decomposing enzymes. The microorganisms included a myxobacterium, several fungi, and a wood-rotting basidiomycete. The fungi included two highly cellulolytic organisms, Myrothecium verrucaria and Trichoderma viride. The myxobacterium used was Sorangium cellulosum and the basidiomycete was Pleurotus ostreatus. The principla substrates employed …

Drag Reduction In Newtonian Polymer Solutions, Harry C. Hershey

Doctoral Dissertations

"Prior work in the area of drag reduction has been mainly limited to aqueous solutions. Theoretical and empirical analyses of the resulting data in aqueous solutions have been hindered by the fact that some polymers cause drag reduction and others do not...This investigation was directed to the study of how the size and configuration of the polymer molecule in solution affected drag reduction and the related phenomenon of turbulence suppression. Apparatuses were designed and built to measure viscometric flow, curves, friction factors, velocity profiles, and normal stresses (by a jet thrust technique developed by Metzner and associates)"--Summary, page 1-2.

An Introduction To Linear Time-Variant Digital Filtering Of Seismic Data, Richard Harold Lassley

Doctoral Dissertations

"The exploration geophysicist is constantly searching for new and better methods for analyzing seismic data. The primary purpose of this dissertation is to introduce linear time-variant digital filters as a technique for the filtering of seismic data. Methods of characterizing linear time-variant digital filters are discussed in general terms. The advantages of the different impulse and frequency responses are cited. In addition, the meanings and possible interpretations of the time and frequency variables introduced are considered. The concept of linear time-variant digital delay filters is presented along with their relationship to impulse responses. A pictorial diagram of discrete time-variant impulse …

The Effect Of Varying Sea Coal Fineness On Sea Coal Activity In Molding Sands, Laurence A. Cooley

Masters Theses

"An experiment was conducted in an attempt to establish a relation between sea coal activity in a facing sand and the particle size of the sea coal added to the sand. It was felt that if a sufficient difference in distribution of volatiles was detected, a correlation between particle size and activity of the sea coal within the test specimens might be established. The lack of positive evidence to support such a relationship is indicative that a variation in particle size does not promote volatile re-deposition within the range of particle sizes investigated for the particular weight per cent of …

Anodic Dissolution And Disintegration Of Tin And Valency Of The Tin Ions Going Into Solution, Mrityunjoy Dutta

Masters Theses

"The increased demand for protective coatings on metals and for non-corrosive alloys has stimulated extensive research on the fundamental behavior of metals in corrosive media. One of the problems still unsolved is the nature of the mechanism of the anodic dissolution of metals like beryllium, zinc, magnesium, cadmium, tin, aluminum, iron in aqueous salt solutions. It has been reported in the literature that these metals show discrepancies which often arise between coulometric data and the weight loss of metal electrodes in various media. Several investigators have proposed different and opposing theories to explain the above deviation. The purpose of the …

A Study Of Sulfide Inclusions In Medium Carbon Steels, Shane Shiang Yen

Masters Theses

"Sulfur is a very important component in steel. Usually is it present as an impurity in commercial steels. In these materials the sulfur content is 0.05 percent maximum but may be higher or lower than this in some steels...It is generally believed that sulfur has a deleterious effect on the mechanical properties of steels. Originally this investigation was to deal with this aspect of sulfur in steels but the work did not progress to this stage. An effort was made to vary the nature of the sulfides in several experimental heats of steel by controlling their composition. Variation in the …

The Eccentric Orifice As A Flow Measuring Device In Small Diameter Pipes, James E. Casale

Masters Theses

"This thesis reports and evaluates the use of an eccentrically placed orifice as a flow measuring device in small pipe sizes. The orifice is placed in a concentric location and moved to increasingly eccentric locations until full eccentricity is reached. At full eccentricity the circumference of the orifice is tangent to the circumference of the pipe. The effects of increasing eccentricity are evaluated for four orifices...Flow coefficients for the orifices in different locations are plotted against Reynolds numbers. The eccentric orifice is a reliable, accurate flow measuring device for metering or controlling the flow of fluids. Design criteria can be …

Maximum Present Value Calculations With Digital Computers, James Boyd Robison

Masters Theses

"This paper discusses maximum present value calculations for a mineral property using digital computers. A semi-quantitative mathematical model to optimize operating conditions is considered. The model is based on a modified cash flow analysis. Many variables affect the solution, and their effect upon present value is described. Selected data (mining rate, costs, reserves, metal sales price, and others) for a hypothetical open pit copper mine are used in a set of solutions for present value. The results are discussed in detail. It is concluded that: (1) Digital computer methods are rapid and useful, (2) Changes in the mining rate, average …

Active Band-Pass Filters Using Twin-Tee Networks, Terry B. Watson

Masters Theses

"The primary objective of this thesis was the design and construction of a set of filters to determine the spectral energy density of random signal data in the spectrum from 10 cps to 20 kcps. The statement of the problem placed rather exacting conditions on the cost and performance of the equipment, and these conditions were met to the extent detailed in the following pages. A secondary objective was the investigation of techniques to improve the performance of band-pass active filters using resistive-capacitive feedback networks. This objective was not achieved to the author's satisfaction, although several promising ideas were discovered"--Abstract, …

Finite Difference Solution For Triangular Plates, Hao-Yang Huang

Masters Theses

"In this thesis the finite difference method is used to solve triangular plates with uniformly distributed transverse load. As a matter of convenience triangular coordinates are used. The supporting conditions as well as the shape of plate are varied. All calculations are performed by digital computer. The patterns of differential operators in triangular coordinates, the deflections of plates, and the moment distributions are shown and discussed. The results obtained for some special cases are compared with published solutions"--Abstract, page i.

Measurement Of Stray Load Loss Of D.C. Machines, Kanaiyalal Ramanlal Shah

Masters Theses

"For many years the standard practice, in calculation of conventional efficiency of d.c. machines, has been to include stray load losses as equal to 1% of the output. This assumption may be true for large, compensated d.c. machines but it is known to be small for smaller, uncompensated, general-purpose, industrial-type machines of open design. An A.I.E.E. Committee on Rotating Machines was formed to investigate whether the present practice of assigning 1% for the stray load loss is justified or not. They reached a conclusion, reported in 1949, after investigating 243 stray loss tests on different motors ranging from 1/2 hp …

Radiation Induced Polymerization Of Methyl Methacrylate, Ko-Hung Liu

Masters Theses

"A study has been made of the gamma radiation effect on the rate of polymerization of methyl methacrylate monomer, and also to determine the effects of the presence of clay of known composition and of other solids on the rate of polymerization. The results indicate that the monomer undergoes polymerization and then degradation as a function of radiation time at a given gamma flux"--Abstract, page ii.

Piezometric Levels And Shallow Aquifers, Dillon And Meramec Spring Quadrangles, Missouri, James Hugh Crouch

Masters Theses

"Little is known about groundwater in carbonate rock; quantitative data about limestone and dolomite aquifers are almost non-existent. Objectives of this study are: identification of shallow aquifers, and yield, occurrence, and piezometric level of groundwater in cherty dolomitic rocks in eastern Phelps County, Missouri. Area studied comprises of the 7.5-minute Dillon and Meramec Spring Quadrangles. The data used were derived from water well logs, interviews with well drillers and owners, and a previously available geologic map.

The Jefferson City, Roubidoux, and Gasconade formations are aquifers. Groundwater in the Jefferson City formation is perched. West and north of Dry Fork creek, …

Temperature Distribution In Thermal Boundary Layers (In Free Convection) Using A Modified Schlieren Method, Philip Ling Chen

Masters Theses

"A simple optical apparatus, the Schlieren interferometer, was constructed for the quantitative investigation of free convection heat transfer from solid bodies. The photographic results, checked by using thermocouples, were used in evaluating the temperature distribution, the key to the solution of these problems. Interpretation of the photographic results was made using the simple calculation for the conventional interferogram and the Dale-Gladstone law. Although the experiments were limited to a heated flat plate and a heated wire, two dimensional test pieces of irregular configuration can be investigated by the same apparatus with simple modifications. The photographs of the conventional Schlieren, the …

Construction Of A Capillary Viscometer And The Study Of Non-Newtonian Liquids, Hsun Kuang Yang

Masters Theses

"A capillary tube viscometer was built for the purpose of investigating the fluid properties of non-Newtonian aqueous CMC and Carbopol solutions. The viscometer was tested with Newtonian liquids (glycerine, water and two different oils) having known viscosities to insure that the viscometer was operating correctly. The shear stress-shear rate data obtained for different concentrations of CMC and Carbopol solutions were correlated using the simple power law model. The power law constants were only slightly affected by saturating the solution with iodine and carbon tetrachloride. Aging had very little effect on the viscosities of the CMC solutions but had a considerable …