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Continuous Countercurrent Evaporation Through Porous Water-Repellent Membrane With Pressure Above Atmospheric, Yung C. Hsu

Masters Theses

"An experimental method for measuring mass transfer rates at pressures above atmospheric has been developed for the case of continuous countercurrent evaporation through porous water-repellent membranes. The final developed equipment is suitable for operation under pressures up to 50 psig and at temperatures near the boiling point of 7% salt water when high flow rates are reached. Rates of evaporation of water through the membrane were measured, and the data and results were used to examine the effects of operating conditions on the over-all mass transfer resistance. Least squares equations for fitting the data were also obtained. Over-all mass transfer …

A Programmed Synthesis Procedure For Asynchronous Sequential Circuits, Robert Judson Smith

Masters Theses

"The synthesis procedure for large asynchronous normal fundamental-mode sequential circuits is time-consuming and tedious when performed manually. This paper describes a series of computer programs which, given a machine specification in flow table form, automatically produces simplified normal form implementation design equations. The user may specify that either minimum-variable state assignments, or more rapidly generated near-minimum-variable codes be found. Next-state equations are formed using the generated state assignments and converted to simplified sums of products. Sample machines having flow tables of up to eighteen rows by four columns are synthesized"--Abstract, page ii.

A Transmission Electron Microscopy Study Of Some High Strength Plain Carbon Steels, George Joseph Vytanovych

Masters Theses

"Methods of preparing foils of high strength, heat treated, plain carbon steels for examination in the electron microscope by the transmission technique were perfected and are described. Two processes for the initial thinning of a bulk sample were successful. A chemical process was found to be more rapid but not satisfactory for small samples. A mechanical process was slower, but was applicable to the smaller specimens. Electro-polishing the thinned material yielded acceptable foils from which photomicrographs of good quality were obtained. The microstructure of the high strength steel samples showed typical tempered martensite. No reasons for the differences in ductility …

Minimization And Generation Of Next-State Expressions For Asynchronous Sequential Circuits, Gary Keith Maki

Masters Theses

"One step in the synthesis procedure for realizing an asynchronous sequential circuit that is operating in fundamental mode is to obtain an internal-state assignment that will realize the operations of the circuit. Often the procedures that are used in accomplishing the above task generate several satisfactory assignments. The first part of this paper presents a method that will enable one to predict which of the internal-state assignments will yield a simpler set of next-state expressions. A second topic treated in this paper is one of presenting a method to generate the next-state expressions for an asynchronous sequential circuit directly from …

The Effect Of Concentration On The Viscosity Of Dilute And Moderately Concentrated Polymer Solutions, Hwa Luh

Masters Theses

"The effect of concentration on the viscosity of dilute and moderately concentrated polymer solutions was studied for eight narrow molecular weight polystyrene samples (900

Scanning Properties Of Unsymmetrically Loaded Aperture Arrays, Gary Dean Brunner

Masters Theses

"Radiation patterns resulting from an array of waveguide-fed apertures, filled with assymmetrically [sic] cut dielectric inserts, in an infinite ground plane were investigated. The results of Blumberg and Hemmen concerning single apertures were applied to a two-aperture array, with emphasis upon obtaining an array capable of scanning in the far field through changes in the permittivity of the assymmetrically [sic] cut dielectric inserts. Scanning was shown to be possible with up to a 60⁰ scan angle with a "push-pull" method of varying permittivities, in which the permittivity of one insert is raised while the other is lowered. The aperture field …

Annealing Characteristics Of Neutron Irradiated Silicon Transistors, Joseph Robert Chott

Masters Theses

"When a transistor is subjected to neutron irradiation, a component of base current proportional to neutron fluence is induced. From the effects of annealing on the base and collector currents, the conclusion was drawn that there is an apparent difference in the annealing characteristics between the neutral and the space-charge regions of the semiconductor device. This study of the anomalous annealing indicates that the neutron-induced component of base current is a result of one, or a combination, of the following mechanisms: a quasi-tunneling recombination phenomena in the emitter-base space-charge region, or an influence of the p-n junction electric field on …

The Measurement Of Explosively Induced Stresses In Rock-Like Materials With A Capacitive Transducer, Vincent Paul Crane

Masters Theses

"A capacitive transducer was developed for measuring the free surface motion in Hydrostone blocks loaded by an explosive plane wave generator approximately one foot from the specimen. The charge to specimen distance was adjusted to produce a single spall, the position of the fracture being noted on the recovered specimen. The longitudinal wave velocity in each specimen was determined by the ultrasonic pulse technique before each shot. From the above measurements the stress, strain and strain rate at the point of fracture were determined. An attempt was made to determine the actual fracture time with imbedded [sic] conductive graphite rods, …

A Study Of An Electric Method To Excite And Detect Acoustic Waves In Solids, John H. Stevens

Masters Theses

"This experiment has demonstrated that it is possible to generate pulses of acoustic waves in an aluminum single crystal by the direct use of the tensile stress associated with an electric field at the surface of a conductor, and it is possible to detect these waves with a biased, capacitive pickup transducer"--Abstract, page ii.

Noble Gases In The Earth And Its Atmosphere, Robert Anthony Canalas

Masters Theses

"Abundance of noble gases extracted from Fig Tree Shale exhibit a marked deviation from the gas content of eclogitic rocks purported to be mantle material. The abundances of the heavy noble gases in shale were found to exceed the highest known meteoritic values. The abundances of the lighter noble gases were found to be comparable to the abundances of these gases in typical chondrites.

Temperature gradient analyses show that excess heavy gases are released at low temperatures. This is interpreted to indicate a preferential adsorption of the heavy noble gases on fine-grained sediments when these gases were being released from …

Lattice Constants, Thermal Expansion Coefficients, Densities, And Imperfections In Gold And The Alpha-Phase Of The Gold-Indium System, Vinayak Keshavlal Patel

Masters Theses

"An investigation of structure insensitive properties (lattice parameters, thermal expansion coefficients, densities, and imperfection) of gold and the alpha-phase of the gold-indium system was made. The gold-indium alloys were prepared from high purity (99.999%) gold and indium by melting both metals inside sealed quartz glass tubes which were first evacuated and then filled with helium gas. The solidified alloys were annealed and then examined by x-ray for homogeneity. The lattice constant of 99.999% pure gold at 25⁰C was found to be 4.07894 ł 0.00005 (corrected for refraction) Å. The coefficient of thermal expansion was 13.4 x 10⁻⁶⁰C⁻¹ between 15 and …

An Investigation Of The Effects Of An Impact On Some Of The Mechanical Properties Of Aluminum Alloy 2014-T6, Rajnikant K. Shah

Masters Theses

"Static and impact tests were conducted on an Aluminum alloy 2014-T6 specimen. The purpose of this research was to determine the effects of an impact load on some of the mechanical properties of aluminum. The cross section of the specimen measured 4.438 in. by 3.850 in. and it was 12 in. long. It was equipped with a total of four electric resistance gages connected in two pairs. One pair measured longitudinal strain while the other measured transverse strain. Both gages in each pair were mounted on the opposite sides to cancel the bending effect. In the static tests, load was …

A Subsurface Geologic Study Of Petroleum Possibilities In The Pennsylvanian Rocks Of Concho County, Texas, Gregory Paul Kraus

Masters Theses

"During early Pennsylvanian time the area now occupied by Concho County was a portion of the Texas peninsula, a broad, low arch with a karst topography developing on its exposed Ellenburger surface. A mid-Pennsylvanian marine transgression inundated the arch and it became an area of clear, shallow water deposition favorable to limestone development. Local sedimentation during Strawn time was largely controlled by its position relative to the Llano uplift and surrounding basins. A variety of subsurface maps were constructed for this study essentially utilizing electric log data. The results indicate that limestones of the Strawn platform facies rapidly change in …

Quality Of Surface And Subsurface Water In A Missouri Carbonate Karst Terrain (Dry Fork, Norman, And Benton Creek Watersheds), James Chi Huang

Masters Theses

"Little is known about the effect of carbonate karst terrain on water quality in the United States. Karst topography occurs over a large portion of Missouri and over a significant part of other midwestern states. The objectives of this study were the determination of the quality of surface and subsurface water in carbonate karst terrain and the investigation and evaluation of the effect of rainfall and runoff on water quality in the Meramec Spring area, east of Rolla, Missouri, during both the dry and wet seasons over the period of one year. Water samples were collected at a large number …

Analog Simulation Of A Plug Flow Tubular Reactor, Jon Douglas Carson

Masters Theses

"This thesis stresses the importance of analog and digital computers in the field of reaction kinetics. The analog computer is used to simulate a chemical reaction, the hydrolysis of acetic anhydride. The hydrolysis reaction takes place in a tubular reactor. The reactor is 3/4 inch in diameter and 20 feet long. These reactor dimensions allow the reaction system to approach plug flow, if the reactants flow through the reactor at turbulent flow rates. The physical, reactor, system is used to obtain experimental data for the hydrolysis reaction. The data is obtained at reactor temperatures between 75 and 100°F. Feed concentrations …

Velocity Profiles In Viscoelastic Drag Reducing Solutions, Luis Gustavo Florez E.

Masters Theses

"Turbulent velocity profiles in viscoelastic drag reducing solutions were measured using hot-film anemometer and Pitot tube techniques. Data were obtained in a solution of one per cent aluminium [sic] dioleate in toluene and in 0.2 and 0.4 per cent solutions of polyisobutylene (PIB) L-200 in cyclohexane. Velocity profiles were also obtained for comparison in toluene and cyclohexane by both techniques. By integrating the Pitot tube velocity profiles, large flow rate discrepancies between integrated and measured flow rates were found for the drag reducing polymer and soap solutions. This discrepancy was not observed in the hot-film anemometer measurements. The hot-film anemometer …

The Economics And Design Of Desalination By Evaporation Through Porous, Water-Repellent Membranes, Kuei-Hsiung Yang

Masters Theses

"The economics of desalination by evaporation through porous, water-repellent membranes has been studied in this investigation. Using reasonable assumptions this desalination process was found to be economical with the principal advantage being the simplification of multi-stage flash-type evaporation. Based on this process, two different methods were designed and studied by means of computer calculations for a 10 million gallons product water per stream day desalting plant. One method was based on a membrane evaporator and a heat exchanger and was designated Method I; and a combined evaporation-heat exchanger system was designated at Method II. The major factors affecting the economics …

Fault Detection In Combinational Networks, Alexander Rahm

Masters Theses

"This paper presents an algorithm for locating a failure in combinational logic networks, which is a problem of importance in the maintenance of computer systems. The procedure is based on the "path sensitizing" idea for fault detection. The networks considered are non-redundant, consisting of AND, OR, and NOT elements. The class of faults investigated is that which causes a connection to appear to be logically suck-at-one or stuck-at-zero, and only single failures are treated. It is shown that the failure is generally located to a specific "fault group"--Abstract, page 2.

Mechanisms Of Base-Catalyzed Reactions: Part Iii: The Acidities Of Some Hydroxylic Compounds In T-Butyl Alcohol., Charles Frederick Seger

Masters Theses

"The K_HA of water and five alcohols were determined in t̲-butyl alcohol employing sodium and potassium t̲-butoxides. The order of acidity is methanol>water>ethanol> 2-propanol~cyclohexanol>methanol. It was also shown that potassium t̲-butoxide was twice as strong a base as sodium t̲-butoxide. A spectrophotometric method was employed with p-nitroaniline as the indicator. Calculations were made employing the methods of Stearns and Wheland and of Hine and Hine"--Abstract, page iii.

Programmed State Assignment Algorithms For Asynchronous Sequential Machines., Wayne L. Schoeffel

Masters Theses

"An important step in the synthesis procedure for realizing a normal fundamental mode asynchronous sequential circuit is the internal state assignment. Although systematic methods have been developed to construct minimum-transition-time state assignments, they become long and tedious with hand methods for machines with more than 7 or 8 internal states. To extend the application of these algorithms to larger problems, this paper presents an efficient digital computer program for generating minimum-variable state assignments. An alternate program is also presented which, though shorter, does not guarantee a minimum-variable assignment"--Abstract, page ii.

The Relation Of Heat Transfer To Mass Transfer In Vaporization Through Porous Membranes., Chung-Liang Yeh

Masters Theses

"The object of this investigation was to study the mass and heat transport phenomena through porous, water-repellent membranes. The investigation concerned the rate of vaporization of salt water at a porous membrane surface, mass transfer of vapor through the pores of the membrane, condensation of vapor on the other surface of the membrane in contact with a coolant (fresh water), and the undesired heat transfer by conduction through the membrane. The water-repellent membrane separated the two liquid phases by surface tension forces and provided a vapor phase in its pores. Membranes made of fiberglass and Teflon had been found suitable …

Negative Resistance In Cadmium Sulfide., John William Mohr

Masters Theses

"A light-sensitive, negative-resistance phenomenon has been observed in a special two-terminal CdS device fabricated from selected single crystals. The device differs from those used in previous investigations in that one end of the device was masked to keep out visible light and that the phenomenon was observed at room temperature. A method is described which enables the phenomenon to be observed on a reproducible basis. It was found that the CdS single crystal must have a relatively high density of traps. Possible mechanisms which may contribute to the phenomenon are discussed"--Abstract, page ii.

Film Boiling From Horizontal Plates With Low Thermal Capacity, K. M. Ragsdell

Masters Theses

"The object of this investigation was to obtain data for saturated film pool boiling from a low thermal capacity flat plate at atmospheric pressure. A test plate, constructed from resistance strip, was placed horizontally in a pool of liquid, and was heated electrically. Refrigerant-11 and nitrogen were used as the boiling liquids. Heat transfer results were obtained in both fluids over a temperature range of approximately 1200F⁰ (400-1600⁰F). Surface size, roughness and orientation effects were observed for flat horizontal heated surfaces with one dimension near the most dangerous wavelength. No surface material effect was observed. Excellent correlation of the data …

Studies In Coprecipitation Of Trace Amounts Of Elements, Gerald Delano Schucker

Masters Theses

"A new approach to preconcentration of trace amounts of elements has been demonstrated whereby traces of metals tied up as chelates are coprecipitated on a column of solid organic material. Complete coprecipitation was found to occur within very narrow pH ranges, thereby allowing separation as well as concentration of the elements by careful adjustment of acidity and concentration of chelating agent. The separation is based on the difference in stability constants of the metal chelates. Preliminary studies with different physical forms of the carrier precipitate, indicate adsorptive processes could play a significant role in the mechanism of the column-coprecipitation process. …

Shutdown Reactivity Worth Of Reactor Control Rods By A Subcritical Multiplication Method, Leslie Roger Conner

Masters Theses

"Two modified subcritical multiplication methods for measuring the reactivity worth of control elements were developed and investigated. The first involved the calibration of a subcritical count interval by the asymptotic period method. The second involved the calibration of a subcritical count interval by a rod interchange with the reactor regulating rod which had previously been calibrated by the asymptotic period method. The accuracy of these methods is relatively poor. this inaccuracy is due to shadowing effects and to the spatial harmonics which exist in the core. An investigation of the spatial harmonics to determine the best location for the neutron …

Mass Transfer From A Torus Shaped Body, Kamalesh Suryakant Desai

Masters Theses

"A mathematical model for molecular diffusion in a torus was derived. Handlos and Baron have assumed a system of tori in their eddy diffusion model for liquid-liquid extraction from droplets. However, the effect of torus curvature was neglected in their studies. Since they assumed the torus could be represented by an infinite cylinder. In this study, the effect of torus curvature was considered on the concentration profile and the fraction of the solute extracted. The partial differential equation describing the model consists of three independent variables, and a finite difference technique was employed for the solution of the mathematical model. …

Plastic Deformation Of Thin Plates With A Spherical Indenter, Benjamin Jen-An Chang

Masters Theses

"A method of determining the stress distribution in a thin plate deformed with a spherical indenter is presented in this report. The analysis is formulated in cylindrical coordinates and utilizes the basic principles of plasticity (von Mises yield criteria, Luwig stress-strain equation, Hencky Deformation theory, etc.). The problem is solved through the utility of a displacement function that, by virtue of its definition, automatically assures that the condition of volume constancy is satisfied. The boundary conditions are selected on the basis of having average, or integrated, effects corresponding to the physical constraints of the problem. Numerical integration is introduced to …

Compressive Creep Of High Alumina Refractories, Vernon Lee Burdick

Masters Theses

"The deformation of refractory materials consisting of 90% sintered or fused alumina plus 10% silica was measured at temperatures from 1450 to 1515⁰C and a compressive stress of 100 psi. Creep rates and activation energies were determined from the steady state portion of deformation vs. time data and correlated with the mineralogical composition. Supplemental measurements included x-ray diffraction, electron probe microanalysis, apparent porosity and tensile strength. conditions having an important effect upon the mineralolgical composition were: (1) duration of heat treatment, (2) amount of sodium oxide impurity, and (3) reactivity of the alumina grain. Prolonged heat treatment and sodium oxide …

The Design Of A Drum Memory System, Frederick W. Lynch

Masters Theses

"Three methods for obtaining an auxiliary memory for an SCC-650 (Scientific Control Corporation) digital computer are presented. A logic design is then developed on the basis of using the drum and write circuits from an available IBM-650 digital computer and constructing the remaining logic functions. The results of the logic design are the transfer equations necessary to implement the memory system"--Abstract, page ii.

An X-Ray Study Of The Lead Titanate-Bismuth Chromate System, Tsen-Tsou Shih

Masters Theses

"The lead titanate-bismuth chromate system was studied employing x-ray diffraction techniques at both room and high temperatures. Samples were prepared by sintering stoichiometric mixtures of the corresponding oxides followed by air quenching. Bismuth chromate was prepared by resintering and air quenching for four times. The results of the analyses show the structure of BiCrO₃ to be tetragonal with 8 molecules per unit cell. Solid solutions exist over the range 100 to 35 mole percent PbTiO₃ of the binary system, although small amounts of other phases are present in some regions. X-ray data at room temperature indicate the tetragonal perovskite structure …