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The Design Criteria Of A Phoswich Transducer., Richard L. Crawford

Electrical and Computer Engineering ETDs

This dissertation is an experimental and theoretical treatise on the design criteria of a phoswich transducer. The major emphasis is on the application in a gamma-ray spectrometer. The conversion efficiency, gamma-ray cross sections, response to charged particles, luminescence decay time, spectral response and physical qualities are discussed, in considerable detail, in making the optimum choices for the inorganic crystal and the organic phosphor which will act as the charged particle anticoincident shield. The effect of the thickness of the anticoincident shield on resolution, the percentage of gamma-rays absorbed, the percentage of gamma-rays that are atten­uated in energy and the lower …

Predicting Current Gain Degradation In Npn Silicon Transistors After Irradiation By High-Energy Neutrons, Jerry A. Hood

Electrical and Computer Engineering ETDs

The damage discussed in this report is permanent and remains after all transient ionization has decayed. The damage which predominantly affects the electrical characteristics of a transistor is the creation of "vacancies" and "interstitials" in the lattice structure. These defects are created when an atom is knocked from its position and leaves a vacancy in the lattice. The atom comes to rest in a position out of the lattice structure and is known as interstitial. These atoms are knocked from their positions by the irradiating neutrons or by an interstitial traveling through the crystal. These defects occur in localized clusters …

Temperature Distribution And Thermal Stresses In Radiation-Cooled Circular Cylinders, William E. Putman Jr.

Mechanical Engineering ETDs

This study involves the determination of the transient temperature distribution and thermal stresses in a solid circular cylinder cooled by thermal radiation. The analytical solutions are presented in dimensionless form. Theoretical results are shown for temperature distribution and thermal stresses in the nondimensional form. Certain of these results are given in the dimensional form for the model cylinder used in this investigation.

The uranium-zirconium prototype element was thought to be undesirable for this investigation. Therefore, similitude was used to select a model which could be used for the experimental work. A solid, cylindrical, epoxy model was constructed, and thermocouples were …

Electric Fields From Airborne Vertical And Horizontal Dipoles At Very-Low Frequencies, A. H. Garry Gibson

Electrical and Computer Engineering ETDs

A gap exists in present-day knowledge of the electric fields in the earth which are radiated from elevated antenna structures in the earth-air-ionosphere waveguide. It is the purpose of this paper to present a method of estimating the electric field at the earth-air boundary, caused by elevated antenna structures, and to show the existence of new phenomena that may lead to an improved design of communication systems.

Fourth Annual Performance Survey Of Reinforced Concrete Pipe Culverts, Ronald D. Hughes

Kentucky Transportation Center Research Report

A stylized, rational criterion for the structural design and installation of reinforced concrete pipe culverts was developed by the Bureau of Public Roads in cooperation with Prof. M. G. Spangler of Iowa State College and the American Concrete Pipe Association and was distributed to the various state highway agencies, April 4, 1957, as Circular Memorandum 22-40.* The criterion was intended to bring together and simplify methods for computing the strengths required for various fill heights and conditions of bedding. The several highway agencies were urged to adopt the criterion for use on all Federal-aid projects and accordingly, the Kentucky Department …

A Study Of The Stabilization Of Putnam Silt Loam With Large Organic Cations, George C. Bennett Jr.

Masters Theses

"Laboratory tests were conducted to determine if Aliquat, a quaternary ammonium chloride compound, could be used to change the physical properties of Putnam silt loam. The effects of adding varying amounts of Aliquat to the soil were measured in terms of the results of Atterberg limits tests, the moisture-density relationship, unconfined and triaxial compressive strength, and capillary adsorption characteristics. A small change in the Atterberg limits, the optimum moisture content, and the maximum dry density was noted. An increase in the unconfined compressive strength and a reduction in the moisture adsorption potential was accomplished by the addition of 0.25 and …

Laboratory Thermal Expansion Measuring Techniques Applied To Bituminous Concrete : Informational Report, C. C. Hooks, William Harner Goetz

JTRP Technical Reports

No abstract provided.

The Plastic Behavior Of Beams With Butt Welded Connections., Paul George Hayes

Masters Theses

"The purpose of this study is to determine the length of butt welds required to develop the full plastic section modulus of a 6 WF 20 rolled section of A-36 steel. The members were electric arc welded with LR 6070 electrodes. Two-point loading was used to develop a zone of pure moment with zero shear where these members were joined.

At the cross-section to be welded, all the flange edges were prepared to receive a single-vee butt weld and the webs were prepared for a double-vee butt weld. In all cases the full length of the flange was welded. However, …

Time Optimum Switching Zones In Multiple-Valued Control Systems, Jack Leroy Crawford

Masters Theses

"Present control system theory provides the criteria necessary to bring a second-order single-valued system to rest in a minimum time after a step input. The bang-bang type controller has been developed to obtain this optimum response.

However, existing theory fails to provide the necessary information to obtain the optimum response from a second-order rotational system when multiple values of angular position are allowed. This thesis extends the control theory to include these multiple-valued systems by showing the existence of what are called optimum switching zones. These zones predict which of the infinite number of switching curves in a multiple-valued system …

Investigations Of The Feasibility Of Transporting Ore In Open-Flumes., Kirtikant R. Sheth

Masters Theses

"Considerable effort has been expended and many data are published on developing the technologies of pipeline transportation and hydraulic hoisting. However, comparatively little information is available on the techniques of hydraulic mining, and nearly none ii is reported on conveying slurries in open flumes. For this reason, the author chose to investigate some of the parameters that influence open-flume transport.

It was found that Durand has assembled the findings of several investigators into a simple mathematical expression which is accepted as a standard for designing slurry pipelines. ·Further investigation by the writer revealed that Durand's formula, with only minor modification, …

Optimalization By Peak-Holding, Curtis W. Dodd

Masters Theses

"The problem presented is a study of the peak-holding method of optimalization. This method applies to a system that has an extremum.

After describing how the complete system, consisting of the controller and the controlled system, works; variations in the controller are presented. These variations are changes in the final stage of the controller, the servo. A phase-plane analysis shows how the output of the controlled system varies with its rate of change. Limitations are presented which tell why the system cannot be kept at its peak value at all times. Finally an analog simulation is used to study the …

Solid-Phase Welding Of Nodular Iron To Low Carbon Steel., Scott H. Carriere

Masters Theses

“This paper presents an experimental investigation of the possibility of using solid-phase welding to join nodular iron to low carbon steel. Included is a review of available literature on solid-phase welding, tracing its origin from early Egypt to the present day. There was no previously reported work found on the welding of nodular iron to steel.

Experiments were performed to determine what temperature-pressure combination gave the greatest ultimate tensile strength These experiments resulted in the best welds being produced with an end load of 7000 pounds (35.700 psi) on a half inch diameter sample. The majority of these welds proved …

The Effect Of Plastic Deformations On Grain Boundaries., Jayendra Jamnadas Shah

Masters Theses

"The purpose of this study is to determine the effect of the plastic deformations on the grain boundaries and the grain structure of mild steel. Five beams tested were of A-36 steel and of 6 WF 20 rolled section. Central loading was used to develop a plastic tinge at the cent1:1r.

At the center, where a plastic hinge was formed, the effect of the plastic deformations on the grain structure was severe in all the samples taken from the tension side of all plastically or partially plastically loaded beams. In fully plastically loaded beams this effect had spread on both …

Effect Of Internal Pressure On Compressive Buckling Stress Of A Cylindrical Shell Under Eccentric Loading, Chao-Ping Chu

Masters Theses

“In this paper, an investigation was made of a thin- walled cylindrical shell under compressive load with various eccentricities and internal pressures to study the effect of the internal pressure on the compressive buckling stress of the shell.

So far, theoretical methods have not been devised to solve this problem; therefore, an experimental study was carried out. The experimental results indicated that the buckling load of the shell decreases as the eccentricity increases, that the buckling stress increases as the eccentricity increases, and that the change in buckling stress increases with an increase of internal pressure and is very nearly …

An Investigation Of The Adaptability Of The Linvill Model For Transistor Synthesis, John A. Reagan

Masters Theses

"The Linvill transistor model may be used for transistor synthesis if the model accurately approximates transistor response and may be readily simulated on an analog computer. Experiments were performed on a transistor to determine the Linvill model parameters. The transistor's large-signal transient response was investigated by pulsing the emitter with a current that drove the transistor from the active region of operation into saturation. The same problem solved experimentally was then solved analytically by replacing the transistor with the Linvill model. The experiment was then simulated on an analog computer by using the equations that govern the Linvill model's response. …

A Laboratory Study Of The Effect Of Wettability Of Residual Oil Saturation In Artificial Cores., Socrates Nicholas Potamianos

Masters Theses

"In the past much emphasis has been placed on various studies of reservoir rock and fluid surface properties and their relation to the different oil recovery processes. Several laboratory methods (1, 2, 3) ^l/have been used by different investigators to obtain a more fundamental understanding of the many factors which have an influence on the oil recovery from reservoir rocks"--Introduction, p. 1

Design, Construction And Characterization Of A 10-Liter Batch Pilot Plant Fermentor., Sylvester Ogden

Masters Theses

"A 10-liter batch type pilot plant fermentor has been designed and constructed. The design incorporated most of the desirable features of previous designs reported in the literature.

The stainless steel fermentor has a multi-speed agitator and aeration rates as high as 15 cubic feet per hour. Temperature indicating, temperature controlling, pH measuring, and automatic foam controlling systems are included in the design.

Sulfite oxidation rates have been determined for the unit at 15 operating conditions. A maximum sulfite oxidation rate of 1060 millimoles of oxygen per liter per hour has been obtained.

Fermentation using a Torulopsis utilis yeast culture has …

Investigation Of Zero Sidesway For Rigid Frames, Dolatray S. Mehta

Masters Theses

"This study was made to determine the location of a point at which a vertical load may be applied to a rigid frame structure and produce zero sidesway, the so called zero sidesway axis. For concentrated loads equations have been derived for zero sidesway. For uniform and triangular loads graphs showing zero sidesway for various ratios of column and beam stiffnesses and height ratios have been plotted"--Abstract, page ii.

A Model System For The Investigation Of The Effect Of Soil Particles On The Microbial Decomposition Of Herbicides : Progress Report, Walter Joseph Farmer

JTRP Technical Reports

No abstract provided.

Thermal Resistance Of Bonds And Contacts, David Marion Lewis

Masters Theses

"The adhesive and sealant Industry has more than kept pace with our rapidly expanding technology of today. This growth has left the standardization of data on adhesives far behind and lack of this data is obvious. Of the many applications, particularly as related to space technology and energy conversion, the resistance to the flow of heat offered by the bond layer is of considerable importance.

Little information is available on the effect of adhesives on heat transfer. In connection with their work on honeycomb panels, Rankle, Gier, and Bevans (7) determined the thermal resistance of the particular type of adhesives …

The Effect Of Cation Size Of Xanthate Collectors In Sulphide Flotation., R. W. Bourne

Masters Theses

"Batch flotation tests on Utah Copper ore were used to show the effect of collector cation size.

The results obtained were:

(1) Recovery of copper in the concentrate decreases with increase in the size of the collector cation.

(2) Increased recovery with ethyl over that for amyl with a given cation.

(3) No beneficial recovery with sulphur enriched xanthates.

Statistical techniques were used to ascertain if significant differences in results were present"--Abstract, p. i

Analysis Of Space Frames By Moment Distribution., Ting-Hwa Wang

Masters Theses

"This work presents an analysis of space frames and planar frames loaded in different planes by the method of moment distribution and the theory of superposition. From this analysis it is found that the torsional stiffness of frame members has a great effect on the final bending moments when twisting moments are applied to the frame. The analysis of space frames considering the forces, stresses, and moments in all three dimensions always yields a design more accurate and economical in material than the traditional planar frame analysis"--Abstract, p. i

A Study Of The Phase Behavior Of Carbon Dioxide-Methane-Normal Decane Systems, Raja Audi Mansoor

Masters Theses

“The effect of carbon dioxide concentration, on solubility has been studied for several carbon dioxide-methane-n-decane systems. Experimental results were obtained using differential vaporization tests. Computational results were obtained using equilibrium constants.

The relation between solubility, bubble point pressure and solution carbon dioxide is presented. A ternary diagram showing the bubble point pressure behavior as a function of system composition is also presented”--Abstract, page ii.

The Design, Construction, And Evaluation Of A Vortex Stabilized Plasma Generator, Ronald Ray Williams

Masters Theses

“This report presents the design, construction, and evaluation of a vortex stabilized arc plasma generation facility operating on argon.

The facility consisted of five basic systems; the plasma genera- tor, the electrical power system, the argon flow system, the cooling system, and instrumentation.

The facility was designed to meet four general requirements; stable arc operation, low electrode deterioration, low cost of construction, and provisions for determination of the operating characteristics and thermal properties of the plasma.

Experimental results obtained in the laboratory agreed well with the design conditions. The rate of energy dissipated in the electric arc varied from 7. …

Synthesis Of Unity-Gain Rc Networks From Second Degree Transfer Functions., Ronald L. Mcnally

Masters Theses

"A synthesis procedure is presented which realizes second order open circuit transfer functions. This procedure is developed using parallel networks. The transfer functions for each parallel network are obtained by use of separation parameters. Two constraints are used in the development: first, the realized network must be an RC network; second, the desired multiplicative gain constant must be realized. With these constaints a parameter space is developed which aids in the selection of the proper parallel networks to be combined. Necessary and sufficient conditions are developed which are used to test the transfer functions. The realization simply consists of the …

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 …

A Preliminary Study Of The Controlled Crystallization Of A Bottle Glass., Narayan M. Sedalia

Masters Theses

The effect of addition of Ti0₂ as a nucleating agent was studied with a bottle glass composition of 74 weight percent Si0₂, l percent Al₂O₃, 5.4 percent Cao, 3.7 percent MgO, 15. 3 percent Na₂O, and 0.6 percent K₂O as a base or original composition. The addition of titanium dioxide ii varied from 3 to 20 weight percent. The composition of this bottle glass was changed by increasing the following ingredients and keeping the other ingredients in the same ratios:

1. Increased 5 weight percent of Al₂O …

Compaction Characteristics Of Fine Grained Soils., Lewis Clyburn Sowell

Masters Theses

"The existing theories of compaction of soi Is are reviewed. The effect of varying the compactive effort on dry density, optimum moisture content, and compressive strength for three fine grained soils is investigated. These samples consist of si I ty clay (CL), plastic clay (CH), and loess (ML). The test results indicate that compactive effort has an important effect on the shape of the moisture density curve and that a potential for over compaction increases with a higher plastic index and c l ay content. At water contents above the Standard AASHO optimum value, the compressive strength is not appreciably …

Theoretical Investigation Of Steam Jet Cleaning, Jaswant T. Lotwala

Masters Theses

"Steam cleaning methods are used by industries to remove mass of dirt and grease deposits from machine parts and other surfaces. It is necessary to know the rate at which this mass can be removed from a surface. The present investigation was made to determine this rate of mass removal. The mass transfer rate is influenced by two phenomena; namely, heat transfer and momentum transfer. Both of these were discussed and the results obtained from the analysis were used in determining the total mass transfer rate. The effects of various parameters, such as density and velocity of the cleaning fluid, …

High Order Bang Bang Control System., Shing-Chou Pi

Masters Theses

"The problem undertaken in this thesis is to find a representation of a nonlinear controller to minimize the response time of a limited input plant whose transfer function has N negative real poles. The extension of the phase-space method to automatic control systems described by high-order differential equations with a general high-order input is considered.

The design utilizes a maximum effort controller whose switching time is determined by the concept of switching hypersurfaces of the system in N-dimensional phase space and the concept of a distance function, which is & geometric length between the initial state point and the switching …