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A Study Of The Evaporation Rates Of Small Freely Falling Water Droplets, Hugh Alan Duguid Jan 1969

A Study Of The Evaporation Rates Of Small Freely Falling Water Droplets, Hugh Alan Duguid

Masters Theses

"The evaporation rates of small (radium 3-9µ), freely falling water droplets were determined. the droplets, produced in a diffusion cloud chamber, were allowed to fall through air of known relative humidity (95-100%) and at three ambient temperatures (25C, 30C, and 35C) in a vertical drift tube. the rates of evaporation were ascertained by recording the drop positions on film at fixed time intervals. The results are compared with several existing theories, and are found to lie between the formulation of Kinzer and Gunn, and the quasistationary theory based on Maxwell's equation"--Abstract, page ii.


A Digital Technique For Combining Frequency Standards, Lynn James Hawkey Jan 1969

A Digital Technique For Combining Frequency Standards, Lynn James Hawkey

Masters Theses

"A new technique for combining multiple frequency standards into a single timing reference based on the average of the frequency of each input is described. The uniqueness of this approach is that it is an all-digital scheme utilizing delay lines and high-speed logic elements currently available. The present and future applications of combiners are discussed, the requirements are highlighted, several digital solutions are briefly described, and the detailed block diagrams and characteristics of a particular general purpose combiner are presented. It is suggested that the optimum combiner include a stable quartz crystal oscillator with a frequency control feature. The output …


Design Of R-C-C-R Spatial Mechanism, Kao-Chien Hsei Jan 1969

Design Of R-C-C-R Spatial Mechanism, Kao-Chien Hsei

Masters Theses

"An analysis to design a particular R-C-C-R spatial mechanism was developed using tensor notations and operations. This specific R-C-C-R spatial mechanism can be used to couple two shafts intersected at a skew angle with constant rotating speed ratio. This skew angle, or bending angle of the two shaft, may vary from 30 up to 180 degrees. The governing equations of relative positions of the mechanism were formulated as a function of two variables: the bending angle of the shafts and the rotating angle of the input link. To exemplify the various design conditions, the design parameter versus the bending angle …


Thermal-Fatigue Of Type 304 Stainless Steel, Gajinder Bir Singh Arora Jan 1969

Thermal-Fatigue Of Type 304 Stainless Steel, Gajinder Bir Singh Arora

Masters Theses

"Thermal fatigue resistance of unrestrained samples of type 304 stainless steel has been investigated under different test conditions. The following studies are reported: (a) effects of heating and cooling rates on the initiation of cracks, (b) effects of upper and lower cycle temperatures on the initiation of cracks, (c) effect of water quenching and (d) the manner in which cracks initiated and propagated. It is shown that under cyclic conditions involving maximum temperatures up to 1000°C, the thermal fatigue life of the material decreases rapidly with rise in the maximum temperature of the cycle. The increase in the lower cycle …


Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal Jan 1969

Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal

Masters Theses

"Thermal fatigue is a form of surface failure produced by repeated thermal stresses and is the main cause of die retirement in the die casting industry. A general review of the fundamental and practical aspects of thermal fatigue as encountered in the dies, based on earlier published work, is given and preliminary experiments in an effort to set up a suitable method of testing to study this phenomenon are then described. In the present technique developed to create the thermal conditions experienced by a die steel in aluminum die casting, a small portion of one face of a cylindrical test-piece …


Vibration Of An Internally Damped Tapered Truncated Cantilever Beam, Chimanbhai Magandas Patel Jan 1969

Vibration Of An Internally Damped Tapered Truncated Cantilever Beam, Chimanbhai Magandas Patel

Masters Theses

"This thesis provides a vibration analysis of an internally damped, tapered, truncated, cantilever beam. Using two formulations of the problem based on: (1) Discrete mass and (2) continuous mass distribution, solutions are given for a beam having square cross section with linear depth and linear width variation. A Kelvin viscoelastic material for the beam is assumed. The vibration of the beam is considered to produce plane stress in the material, and the stress-strain relationship is applied only to the strain in the plane of bending. An exact solution for frequency of oscillation, mode shape, and steady state response is obtained …


Fast Neutron Effects On Transistor Scattering Parameters, David Leslie Gray Jan 1969

Fast Neutron Effects On Transistor Scattering Parameters, David Leslie Gray

Masters Theses

"It has not been possible in the past to characterize a transistor or other semiconductor device with regard to its performance in a fast neutron (E>10keV) environment when the device is operated at high (>100 MHz) frequencies. Using the scattering (s-) parameter concept, which regards a device as a two-port "black box", a full characterization of the trends in the neutron bombarded high-frequency performance of a typical transistor can be made. Scattering parameters are not only an accurate means of describing the high-frequency performance of any device, but are now reasonably easily measured with the advent on the …


The Effect Of Aging On The Exfoliation Corrosion Characteristics Of 7178 Aluminum Alloy, J. James Slavick Jan 1969

The Effect Of Aging On The Exfoliation Corrosion Characteristics Of 7178 Aluminum Alloy, J. James Slavick

Masters Theses

"The objective of this investigation was twofold: 1) to determine the effect of the quench-to-artificial aging delay period on the exfoliation corrosion of 7178 aluminum alloy subsequently aged at 250F for 24 hours and 2) to determine the effect of an initial aging treatment at 212F on the tensile properties and exfoliation of 7178 aluminum subsequently aged at 250F. Testing was conducted on 0.125 inch thick sheet. Quench-to-aging delay periods of 0 to 28 days, and initial artificial aging treatments at 212F for 24 and 48 hours were investigated. In addition, the effect of overaging T6 material at 320F for …


A Photoelastic Study Of The Stresses Around An Underground Opening And Its Support System, Alphonse C. Van Besien Jan 1969

A Photoelastic Study Of The Stresses Around An Underground Opening And Its Support System, Alphonse C. Van Besien

Masters Theses

"The stress conditions around openings in rock have long been of interest to the field of rock mechanics. The purpose of this investigation was to determine the stress distribution around an opening with a rib and wall-plate support system. A photoelastic model of the opening (a modified horse-shoe section) was loaded in the centrifuge to determine the effect of body loading. Both the tangential stress and the stress within the rock bench, due to the opening, were determined. The stress conditions within the bench were examined using simulated ribs and a loading frame. Application of the data is discussed, as …


Tunnel Diode Models For Electronic Circuit Analysis Program (Ecap), Carmon Dale Thiems Jan 1969

Tunnel Diode Models For Electronic Circuit Analysis Program (Ecap), Carmon Dale Thiems

Masters Theses

"In this paper ECAP models for the tunnel diode are presented. Results showing the model, the current-voltage charateristics [sic] are discussed. Operation in typical circuits is presented. A summary of the current state of the art in modeling appears in Appendix I. Since ECAP is only structured to accept piecewise-linear models of these devices, that type of model is presented here. All of the models are developed to approximate the typical tunnel diode current-voltage characteristic"--Introduction, page 1.


A Study On Load Transfer Of Model Friction Piles, Richard Milton Franke Jan 1969

A Study On Load Transfer Of Model Friction Piles, Richard Milton Franke

Masters Theses

"Previous investigations concerned with disturbance of soft clay by driving displacement piles are summarized. The initiation of excess pore water pressures due to pile driving, and mechanisms of load transfer are also described, along with the applicapability of model pile testing in analysis of the various phenomena. Load tests were conducted on assorted sizes of model friction piles embedded in sedimented soil samples with consisted of a silt and clay mixture. Pilot holes of various diameters were cut in the samples. A theoretical load distribution curve was used to calculate the load transferred to the soil as a function of …


A Synthesis Procedure Of Distributed Rc Parameter Networks, Chun-Ming Wen Jan 1969

A Synthesis Procedure Of Distributed Rc Parameter Networks, Chun-Ming Wen

Masters Theses

"Synthesis procedures for driving-point functions and transfer functions in the w plane are developed in this thesis. For driving-point functions and transfer functions which are single-valued in s, where s is the complex frequency variable, the synthesis procedures were derived from the extension of the O'Shea's trasformation [sic]. For the transfer functions which satisfy the stability theorem in the w plane, a synthesis procedure is developed by using a distributed-lag element (DL) or a uniform distributed RC (UDRC) network with matched terminations"--Abstract, page ii.


Internal Friction Of Phase Separated Glasses, Scot Walter Taylor Jan 1969

Internal Friction Of Phase Separated Glasses, Scot Walter Taylor

Masters Theses

"The large internal friction peak observed in a 10Li₂O·10Na₂O·80SiO₂ glass was studied as a function of the degree of phase separation. Transmission electron microscopy was used to evaluate the type and degree of phase separation. No observable changes in the temperature position or height of the internal friction peak were observed at successive stages of phase separation. Phase separation of a mixed alkali borosilicate glass also produced no changes in the internal friction peaks. Phase separation is not considered responsible for the large internal friction peak observed in mixed alkali glasses"--Abstract, page ii.


The Influence Of Organic Matter On Shear Strength Of A Cohesive Soil, Kamran Rezvan Jan 1969

The Influence Of Organic Matter On Shear Strength Of A Cohesive Soil, Kamran Rezvan

Masters Theses

"The shearing properties of an organic A̲ horizon of Bryce clay were studied and compared with the properties of the same soil treated with hydrogen peroxide. The treatment was to remove the organic matter and isolate it as a variable. Tests were performed on artificially sedimented samples of the untreated, 75 percent untreated, 50 percent untreated, 25 percent untreated, and the treated soil. The effective stress failure envelopes were found to be higher for the untreated soil than that of the treated. The elastic deformation, however, was larger for the untreated samples. The pore water pressure development due to shearing …


Determination Of Distillation Efficiencies For The Water-Methanol-Acetone System, Chorng Shyong Wang Jan 1969

Determination Of Distillation Efficiencies For The Water-Methanol-Acetone System, Chorng Shyong Wang

Masters Theses

"A pilot-scale, eight-plate, bubble-cap distillation tower with a multi-point temperature recorder and automatic sampling device was used to obtain operating data on temperatures and liquid phase compositions for distillation efficiency studies. The tower was run with a single feed, a total condenser, and a partial reboiler. At steady state, as indicated by constant temperatures, samples were taken and later analyzed by gas chromatography. A digital program was developed to calculate component efficiencies on each plate according to Holland's modified Murphree plate efficiency, utilizing the operating data, and reflux rate, the input and output flows and compositions, and vapor-liquid equilibrium data. …


Investigation Of Free Convection Heat Transfer From An Inclined Flat Plate, Phairojna Sang-Urai Jan 1969

Investigation Of Free Convection Heat Transfer From An Inclined Flat Plate, Phairojna Sang-Urai

Masters Theses

"The experimental investigation was conducted to determine temperature distribution and convective heat transfer coefficients in terms of Nusselt number for an inclined heated flat plate in air. The heated surface of the aluminum flat plate was set facing upward and moved through seven positions from the vertical to the horizontal. The investigation shows that the local Nusselt number can be predicted by Kiekus's solution within 12 per cent for inclination angles from the vertical through 75° from the vertical. In the case of the vertical position, Eckert's solution gives a better prediction. For the horizontal position the results show good …


Stratigraphy And Correlation Of Precambrian Volcanic Rocks, Eminence, Missouri, Henry Hugh Fisher Jan 1969

Stratigraphy And Correlation Of Precambrian Volcanic Rocks, Eminence, Missouri, Henry Hugh Fisher

Masters Theses

"A portion of the Precambrian rocks located in the vicinity of Eminence, Missouri are studied and describes. These rocks are exposed as rhyolitic knobs protruding through hills of Ordovician sediments. The Precambrian rocks under study consist principally of rhyolite, with smaller amounts of tuff and creccis. The rhyolite is a potash rhyolite porphyry, both flow banded and unbanded, with phenocrysts of kaolinized orthoclase in a matrix of quartz and orthoclase. The tuffs contain devitrified glass shards and occasional ash balls such as those exhibited at Cott Mountain. A stratigraphic sequence was determined with the oldest rocks to the south at …


The Incorporation Of Oxygen-18 Into Oxindole Acid By Cells Of Hygrophorous Conicus, William Green Allen Jan 1969

The Incorporation Of Oxygen-18 Into Oxindole Acid By Cells Of Hygrophorous Conicus, William Green Allen

Masters Theses

"To understand the mechanism of a biological oxidation in which oxygen is incorporated into a substrate, it is necessary to determine the origin of the incorporated oxygen. The objective of this investigation was to determine the origin of the oxygen atom incorporated into indoleacetic acid (IAA) by the IAA oxidase of Hygrophorous conicus through the use of oxygen-18. To determine the source of the oxygen atom incorporated into IAA it is necessary to incubate H. conicus cells with tryptamine or IAA in the presence of ¹⁸O₂ and H₂¹⁶O in one case and ¹⁶O₂ and H₂¹⁸O in another. An examination of …


The Influence Of Several Factors On The Rate Of Secondary Compression Of Soil, William Joel Green Jan 1969

The Influence Of Several Factors On The Rate Of Secondary Compression Of Soil, William Joel Green

Masters Theses

"This research program has been undertaken to study the influence of load increment ratio, temperature, and sample thickness on Cα (rate of secondary consolidation) for a high organic content and low organic content soil. Consolidation equipment was designed to produce constant temperatures both above and below ambient, and to accommodate both 3/4 and 1 1/2 inch thick samples. Samples were molded into oedometer rings at the liquid limit. It was found that Cα was independent of the sample thickness and load increment ratio for both the high organic and low organic soils. The influence of temperature on Cα was found …


Telecommunications System Design Considerations For Advanced Logistic Spacecraft, James Myron Romberg Jan 1969

Telecommunications System Design Considerations For Advanced Logistic Spacecraft, James Myron Romberg

Masters Theses

"The telecommunications system design goals and functional requirements for an advanced logistic spacecraft are presented qualitatively. Advanced equipment and techniques that meet these system requirements and goals, that are within the state-of-the-art and that are believed to be economically feasible, are enumerated and described. System emphasis is on unification to minimize RF links and antenna subsystems, and on use of functional redundancy to assure satisfactory performance of critical telecommunication functions. The interaction of the telecommunications system design and the spacecraft mechanical, environmental, electrical, and operational interfaces are described in qualitative and quantitative terms. A practical spectrum of system interface characteristics …


Anodic Behavior Of Semiconducting Insb Single Crystals In Acidic Solutions, Lih-Da Hu Jan 1969

Anodic Behavior Of Semiconducting Insb Single Crystals In Acidic Solutions, Lih-Da Hu

Masters Theses

"Undoped, semiconducting single, n-type, InSb crystals were used to study the different etching behavior of the inverse {111} planes, to determine the apparent electron number of InSb under anodic dissolution (which corresponds to the sum of the absolute values of the oxidation numbers) and to investigate whether or not the inverse {111} planes show potential differences. The In {111}, Sb {111[repeating]}, {110} and {100} faces were highly polished, etched and immersed in various acidic solutions. Several new etch patterns of the inverse {111} faces were observed in giving other possibilities to distinguish both of the planes. The significant differences in …


A Five-Spot Waterflood Process As Applied To The Digital Computer Based On The Prats Technique, Leonard Koederitz Jan 1969

A Five-Spot Waterflood Process As Applied To The Digital Computer Based On The Prats Technique, Leonard Koederitz

Masters Theses

"The technique for the prediction of injection rates and production history of a five-spot secondary recovery field pattern as presented by Prats has been significantly modified to permit rapid and accurate digital applications eliminating the heretofore prohibitive reliance upon electrolytic model results for intermediate data values following water front breakthrough"--Abstract, page i.


A Continuous Method For Determination Of The Evaporation Rate Of Zinc, Paul Alan O'Neill Jan 1969

A Continuous Method For Determination Of The Evaporation Rate Of Zinc, Paul Alan O'Neill

Masters Theses

"A method for determination of the evaporation rate of zinc using a continuous recording balance has been devised. Tests were carried out under an inert gas over the range 600°C to 750°C with a total pressure of 1 atmosphere. It was found that the rate of evaporation doubled with an increase of 50°C in this range. Scanning electron microscope photographs show the crystalline nature of the condensate and the presence of a thin oxide layer on some solidified test samples. This oxide layer reduced the rate of evaporation by retarding the zinc vapor escape from the evaporating surface"--Abstract, Page iii.


Trace Element Anomalies In The Igneous Wall Rocks Of Hydrothermal Veins In The Searchlight District, Nevada, Zuhair Al-Shaieb Jan 1969

Trace Element Anomalies In The Igneous Wall Rocks Of Hydrothermal Veins In The Searchlight District, Nevada, Zuhair Al-Shaieb

Masters Theses

"Two hundred and fifty vein and wall rock samples were collected from Chief of the Hill and the Duplex Mines of Searchlight District, Nevada. The samples were collected along lines approximately normal to the veins. They were analyzed for lead, copper, zinc, silver, gold, arsenic, selenium, and molybdenum using neutron actication analysis and atomic absorption spectrophotometry. Gold, silver, copper, lead and zinc show well-developed anomalies in the wall rocks. In most cases, the concentration of these elements decreases gradually with increasing distance from the vein and reaches background values at a distance of 40-120 feet from the vein. Molybdenum and …


Simulation Of The Cyclic Steam Injection Process In A Petroleum Reservoir By A Finite Difference Mathematical Model, Jean-Claude Bernys Jan 1969

Simulation Of The Cyclic Steam Injection Process In A Petroleum Reservoir By A Finite Difference Mathematical Model, Jean-Claude Bernys

Masters Theses

"A three-phase, one-dimensional radially layered reservoir simulator is programmed for a large memory digital computer. It is designed to provide a practical solution to the problem of determining optimum soak time during an intermittent steam injection process. The general approach is to (1) develop a representative mathematical model which describes the reservoir; and (2) employ a suitable numerical technique to solve the system of equations which comprises this model. The reservoir consists of concentric cylinders around the wellbore, a pay-zone stratified into thermally connected layers limited on the top and on the bottom by an impermeable cap and base rock, …


A Study Of The Correlation Potential Of The Optimum Moisture Content, Maximum Dry Density, And Consolidated Drained Shear Strength Of Plastic Fine-Grained Soils With Index Properties, Marvin Tartt Harris Jan 1969

A Study Of The Correlation Potential Of The Optimum Moisture Content, Maximum Dry Density, And Consolidated Drained Shear Strength Of Plastic Fine-Grained Soils With Index Properties, Marvin Tartt Harris

Masters Theses

"The correlation potential of the compaction properties and the consolidated drained shear strength parameters of plastic fine-grained soils with index properties was investigated in this study. The interrelationships of these properties were derived through graphical and multilinear regression analysis. The compaction properties, optimum moisture content, and maximum dry density were found to be related to many of the index properties. The most important relationships were with the plasticity indices and the percentage of particles smaller than two microns; the highest degree of simple correlation was achieved with the liquid limit. The consolidated drained shear parameters, cohesion, and the angle of …


Apparatus And Techniques For The Plane Wave Analysis Of Acoustic Filters, Victor Hugo Simon Jan 1969

Apparatus And Techniques For The Plane Wave Analysis Of Acoustic Filters, Victor Hugo Simon

Masters Theses

"This thesis describes a method for determining the reflection and transmission characteristics of acoustic filters under static (i.e. no flow) conditions. These characteristics are obtained by the combination of linear plane wave acoustic theory with a sequential experimental procedure. The experimental data necessary for the calculation of the reflection characteristics were obtained from measurements made on the inlet side of the filter with a standing wave tube apparatus. In order to calculate the transmission characteristics of the filter, the standing wave measurements were augmented with measurements taken on both the inlet and outlet side of the filter. This was accomplished …


Reduction Of Inappropriate Behavior Of Two Public Grade School Students By Operant -Conditioning, Ronald Nederhoed Jan 1969

Reduction Of Inappropriate Behavior Of Two Public Grade School Students By Operant -Conditioning, Ronald Nederhoed

Masters Theses

No abstract provided.


Infrared Cooling Near Atmospheric Temperature Inversions And Absorber Concentration Variations, Joey Keith Tuttle Jan 1969

Infrared Cooling Near Atmospheric Temperature Inversions And Absorber Concentration Variations, Joey Keith Tuttle

Masters Theses

"Cooling due to infrared radiation near temperature inversions is investigated. Temperature inversions tend to hold pollution below the inversion level. The pollution itself may contribute to the stability of the inversion by selectively cooling certain portions of the atmosphere. A method is developed for evaluating infrared cooling rates at discreet points in the atmosphere. Several sample calculations are given to demonstrate the effects of variations of absorber concentration and lapse rate"--Abstract, page i.


An Appraisal Of The Lincoln School Program In The Use Of Non-Professionals In The Classroom, Philip W. Phillips Jan 1969

An Appraisal Of The Lincoln School Program In The Use Of Non-Professionals In The Classroom, Philip W. Phillips

Masters Theses

No abstract provided.