Engineering Commons^™

The Dissolution Of Magnesium In Strong Acids And Neutral Solutions, Cheng-Ken Chi

Masters Theses

"The increasing demand for magnesium and magnesium- base alloys in the manufacture of aircraft has stimulated a great amount of research into the corrosion characteristics of these materials. The result of such research has been the development of suitable magnesium alloys and protective coatings to retard corrosion.

The basic mechanism of the anodic dissolution of metals such as magnesium, zinc, and cadmium in salt solutions is not completely known. Several schools of investigators have proposed different and opposing theories to explain the discrepancies which often arise between coulometer data and the weight loss of metal electrodes in certain salt solutions. …

A Study Of Hot Shortness In Steels, Koang-Hwa Kung

Masters Theses

"In this investigation an attempt was made to study the deformation of a number of laboratory-melted and commercial steels. A compressive load was applied to the steels at constant temperature and also during heating. The amounts and rates of deformation in these two types of tests was not consistent: in the constant temperature tests the hot short steels deformed more than the others while they appeared to deform less during heating. Metallographic examination of the sulfides indicated that the sulfides in cast steel are not stable and that they change during heating and hot working"--Introduction, page 2.

A Computer Approach To Transistor Circuit Design, Kwok Chee Hong

Masters Theses

"The design of amplifiers is usually approached through experimental study. This thesis proposes a mathematical approach, using a digital computer to predict the performance of an active transistor circuit (a frequency equalizer circuit to compensate for the RIAA recording frequency characteristics) prior to the actual construction of the physical system. The simple but powerful computer analysis method will be based upon the nodal equations of the complete circuit. The primary aim is to design a circuit which would give a desired frequency-gain characteristic. The complete set of simultaneous complex nodal equations describing the circuit operation is then written. Based on …

Determination Of The Temperature Distribution Of The Ionized Portion Of The Jet From A Vortex Stabilized Plasma Generator Operating On Argon, G. Douglas Schellman

Masters Theses

"The interim thesis deals with the determination of the temperature distribution of a plasma jet operating on argon. It is the purpose of this thesis to present in detail the experimental process used and make a correlation of the experimental and theoretical results.

A copper enclosure was placed around the protruding flame, and the embedded thermocouple readings were taken and recorded. A stagnation temperature probe was inserted in the enclosure and moved both axially and transversely toward the flame taking readings at each pre-chosen interval. The exit temperature of the jet was obtained from a total energy balance.

From the …

The Design And Construction Of A Shock Tube Facility, William Adolph Crede

Masters Theses

"It is the object of this thesis to give an account of the considerations necessary to design, construct, and operate a shock tube facility.

The primary purpose of the facility was to provide a means to study high strength shock waves in physics, chemistry, and aerodynamic applications.

Preliminary designs were undertaken to determine the basic dimensions and related capabilities. Final design, construction and testing of the tube itself was performed by Nooter Corporation in St. Louis, Missouri. Preliminary designs agreed rather closely with final construction.

Experimental testing was confined to the successful operation of all the various components of the …

Turbulence In Journal Bearings, Kashyap R. Mehta

Masters Theses

"In this investigation, an experimental study was performed on a journal bearing under laminar and turbulent flow conditions. Using relationships for friction factor developed previously by other investigators a comparison was made with results of this present investigation. Since the flow changes from laminar to turbulent with a change in speed of rotation, curves for friction factor as a function of speed were plotted. Various attempts to make the recording and measuring systems more sensitive were also made and are discussed in this thesis"--Abstract, page ii.

Heat Transfer Coefficients Across Bonds And Contacts, Eugene Charles Fadler

Masters Theses

"The purpose of this investigation was to experimentally determine heat transfer coefficients across interfaces, including the effects of the thermal conductivity of the adherends, the hardness of the adherends, the bond thickness, and the type of adhesive.

Aluminum alloy, steel, copper, and extruded nylon rods were used as adherends; all 1.875 inches diameter and 8 inches long. Each was cut radially at its midpoint and faced off to the desired surface finish. Bare interface tests were conducted before the adherends were bonded together. The adhesives used were high grade silica refractory cement, two-part epoxy resin adhesive, and thermosetting synthetic rubber-phenolic …

Anodic Dissolution Of Silver In Aqueous Solutions, Jagdish Shantilal Sanghvi

Masters Theses

"Silver and platinum, although not used extensively in industry, find considerable use in specialized work. Silver, because of its much lower cost, is used to a greater extent than platinum. Since silver has a high position in the electromotive series, it is very resistant to chemical attack. It is unaffected by alkaline conditions even at high temperatures and hence silver is used in ladles and molds for producing pure sodium and potassium hydroxides. This and its excellent electrical conductivity makes it a very useful material in circuitry.

It has been reported in the literature that when active metals such as …

Kinetics Of Base-Catalysed Reactions, Kunjvihari Ramanlal Mehta

Masters Theses

"The work of Wulfman on the mechanism of the Michael reactions suggests that the normal Michael reaction is second order kinetically, with the rate being proportional to the concentration of the acceptor and the active form of the addendum. A detailed reaction mechanism of normal Michael reaction was not proposed due to insufficient data which resulted from analytical difficulties. This investigation involves the study of the kinetics of normal Michael reaction from the stand point of base strength, solvent concentration and acidity of the reactants, solvent and products"--Experimental. A. Purpose of Investigation, page 17.

Matching Of A Horn Antenna To Its Dense Surrounding Media By The Use Of Artificial Dielectric Methods, Paul Arthur Ray

Masters Theses

"The purpose of this thesis is to design an artificial dielectric slug to match a horn in a media such as water and to discuss a method of determining experimentally its dielectric properties. The design is based on known artificial dielectric methods. The method of determining the dielectric properties is by microwave waveguide reflection techniques. This thesis deals with the theoretical aspects and suggests an experimental method of determining the practicability of such a matching method"--Abstract, page ii.

Infinite Beams On An Elastic Foundation, Shi-Peing Chang

Masters Theses

"In this paper a partial differential equation for the analysis of beams resting on an elastic foundation under dynamic load is presented. A solution for this equation is derived, and solutions for various boundary conditions of infinite beams resting on an elastic foundation are discussed. The application of the equation is demonstrated by an example of a moving load traveling along an infinite beam"--Abstract, page ii.

The Effect Of Small Alloy Additions On The Quench Induced Texture Of Alpha Uranium, Kenneth Ray Riggs

Masters Theses

"The preferential orientations produced in binary alloys of U-Si and U-Cr on plane sections perpendicular to the direction of heat flow by cooling from beta-phase temperatures were determined. The experimentally determined textures were presented using inverse pole figures. A definite and reproducible relationship was found to exist between the preferred orientation present at any position and the cooling rate which material at the position had experienced. It was found that the concentration of the alloying elements within the ranges studied had little detectable effect upon the observed relationship between the cooling rate and the resulting preferential orientation. It was postulated …

Effects Of Internal Pressure Upon The Buckling Of Thin Circular Cylindrical Shells Under Axial Compression, Leroy E. Thompson

Masters Theses

"An experimental investigation was made of the effects of internal pressure upon the buckling of thin circular cylindrical shells under axial compression. A comparison was made of the experimental and theoretical results; the latter were derived from the large-deflection theory. Results showed that the internal pressure had an appreciable strengthening effect upon the buckling of the cylindrical shell. The comparison showed that the experimental results were lower than the theoretical results for a given internal pressure. The discrepancy between the results can be expected since there were factors not included in the theory: imperfections, end conditions, lengths, and material irregularities"--Abstract, …

A Photoelastic Study Of The Effect Of Certain Geometric Variables On The Plane Stress Distribution In An Electrical Insulator Body, Richard L. Pendleton

Masters Theses

"Photoelastic models were used to indicate stress patterns in various geometrically designed shapes. Each model represented a two-dimensional cross-section of the interior portion of an axially symmetrical porcelain electrical insulator. Five different loading pins were combined with three loading heads to produce eleven models. The maximum stress in each model was determined using a photoelastic method of stress analysis. An attempt was made to select the best structural design to be used in an electrical insulator. The test results indicate that the most desirable stress distribution is obtained using a single step loading pin and that the loading head angle …

Field Permeability Determination Of Partially Saturated Fine Grained Soil, Edward G. Rapp

Masters Theses

"The determination of water permeability through a soil is necessary to estimate seepage losses from small reservoirs. At the present time, the methods available to conduct this determination in partially saturated fine grained soils are expensive and in most cases not commensurate with the cost or importance of the individual structure. This investigation was conducted to evaluate the use of a proposed, potentially inexpensive field procedure in this situation. A modified borehole apparatus was utilized in field tests to determine the permeability of a partially saturated soil deposit in place. Undisturbed samples from the same location were tested in the …

Equivalent Circuit Of Unsymmetrical Inductance Diode Using Linvill Lumped Model, Donald Lawrence Willyard

Masters Theses

"Integrated circuit techniques and applications are rapidly changing the electronics industry. A problem common to both state-of-the-art approaches to integrated circuit fabrication is that of miniaturizing and integrating inductors. It is found that, for a certain range of injection current levels, certain unsymmetrically doped junction diodes have an inductive small-signal impedance. This thesis discusses the theory of inductance diodes and applies finite difference equations and the Linvill lumped model to the differential equations that describe their carrier flow processes. The static I-V characteristic and the small-signal equivalent circuit at high injection densities are derived. The elements (R,L,C) of this equivalent …

Design Of Non-Uniform Linear Antenna Arrays With Digitized Spacing And Amplitude Levels, Jack F. Morris

Masters Theses

"Recent developments in space exploration have shown a need for high resolution, high gain antennas. The introduction of non-uniform linear array theory has provided a means by which arrays may be designed to produce narrow main beams with fewer elements than required by uniform arrays. A general theory has not been developed, however, and the design engineer has been left with only trial-and-error methods with which to work. In this study a technique has been developed by which non-uniform antenna arrays may be synthesized to meet a given set of specifications with reasonable accuracy. The elements of the array are …

An Investigation Of Continuous Prestressed Concrete Structures, Ping-Chi Mao

Masters Theses

"This thesis presents an analysis of the behavior of continuous prestressed concrete structures. From this analysis the governing equations for various types of geometry for prestressing cables are derived. The calculation of fixed-end moments due to the prestressing force using the equations derived is quite cumbersome, however, in order to simplify the calculations, design charts are developed. A cable with reverse curvature is analyzed using the design charts. It is shown that the fixed-end moments calculated by neglecting the effect of reverse curvature differ significantly from the fixed-end moments calculated by considering this effect. Hence the effect of reverse curvature …

Permeability And Additive Absorption And Extraction In Lubricating Greases, Eugene Hsiung-Jen Tu

Masters Theses

"A permeability apparatus was used to measure the permeability coefficients of eight Lithium-Calcium greases and ten Baragel greases in which the viscosity and type of the oil component were varied. The oil present in each grease was used for its permeability measurement.

An improved sample packing technique was developed to improve the repeatability of permeability measurements. Repeatability of ± 3% was achieved. In general the permeability coefficients of the non-soap Baragel greases were higher than those of the lithium-calcium greases with comparable oil components, and those of greases containing paraffinic oils were higher than these containing naphthenic oils. The effect …

Epoxy Resin Admixture For Concrete, Kuo-Chu Hu

Masters Theses

"This thesis describes laboratory tests on concrete having epoxy as an admixture. Cylinders for compression and elastic modulus tests were cured under two different curing conditions, standard laboratory cure and a simulated job cure. Beams cured under laboratory conditions were tested for flexural strength. Test results show the compressive strength increases with an increase of epoxy content for job curing conditions. However, compressive and flexural strengths of specimens cured under laboratory conditions show a slight decrease. The elastic modulus of concrete containing epoxy also decreases in comparison to ordinary concrete"--Abstract, page ii.

The Prediction Of Mix Design Properties For Dense Graded Bituminous Mixtures, Robert Ernest Weeks

Masters Theses

"The purpose of this investigation was to ascertain the feasibility of interpolating values of the physical properties of a dense graded bituminous mix between known values. Also the effects of limestone mineral filler on the properties of a dense graded mix are evaluated. The variables in this study were mineral filler and asphalt cement. Control mixes were established at 2, 6 and 10 percent mineral filler and experimental mixes were prepared at 4 and 8 percent filler. The aggregate consisted of limestone and was mixed with an asphalt cement of 85-100 grade penetration. Al mixes were tested by the Marshall …

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 …

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 …

A Study Of The Work Functions Of Nigerian Industrial Technicians, Olugbenro A. Ajayi

Masters Theses

The Problem and Its Background

Introduction

A curriculum can be developed in several ways. The simplest method is to use the curriculum of another institution without modification. The hazard of such an approach lies in the possibility that the curriculum may not be a good one or, even if satisfactory for the original institution, may not fit into the conditions of the setting where it is to be used. For example, entrance requirements for institutions vary from country to country and from one institution to another.

Another method is to study a number of curriculums and develop a composite curriculum …

Reliability Of Aircraft Altitude Estimates By Ground Observers, Euegene W. Benson

Masters Theses

No abstract provided.

Generalized Programs For Heat Transfer Analysis., Ceylung Chu

Masters Theses

"This report presents numerical methods for calculating temperature distributions in any physical system in which heat transfer is taking place. The syste.11 may be at either a steadystate condition or a transient condition. The temperature distribution may itself be or primary interest, or it may be used further to calculate the flow or heat or thermal stress.

The system under investigation is divided into a certain number of subdivisions, or so-called "regions". A reference point (node point) will be taken as representative for the region which includes that point. The temperature at the "node point11 is taken to be the …

Experimental Evaluation Of Thermal Stresses On The Outer Surface Of A Thick-Walled Tube., Vinodray T. Patel

Masters Theses

"In this investigation an attempt has been made to measure thermal stresses on the outer surface of a thick- walled tube. The inside surface was heated by steam passing through the tube while the outer surface was cooled by water. Two temperature compensated strain gages were used to measure strains in the tangential and axial directions respectively. The advantage of using this type of strain gage is to avoid the use of a dummy gage to compensate for the temperature effect.

The analytical solution to the problem was derived and the values of thermal stresses were calculated theoretically and compared …

Zirconium Chloride Nuclear Battery, Lonnie J. Shalton

Masters Theses

"An investigation of the neutron absorption characteristics of zirconium chloride was made to verify the reports of Chicago Development Corporation (5810 47th Ave., Riverdale, Md.) that ZrCl Blight be used as a power source for a nuclear battery. The company detected what they believed to be a beta current when the ZrCl was bombarded with neutrons from a slightly enriched uranium source. Investigation using higher powered neutron sources revealed that such a current was highly improbable and the company incorrectly interpeted the phenomena. Reports in the literature also confirmed that an electric current from the ZrCl using a low powered …