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Phase Equilibrium And Thermodynamic Study Of Lime-Iron Oxide Solid Solutions, Shin Suk Kang
Phase Equilibrium And Thermodynamic Study Of Lime-Iron Oxide Solid Solutions, Shin Suk Kang
Masters Theses
"The solubility limits of iron oxide in solid lime were determined as a function of oxygen pressure at 1300º and 1400ºG in the system CaO-iron oxide. The stability region of dicalcium ferrite was determined with respect to formation of lime-iron oxide solid solution and liquid oxide. In addition, the hydration behavior in moist air of pure lime and sintered mixtures of lime and iron oxide was also observed. Pelletized samples were equilibrated under known oxygen partial pressures and quenched. Phases present in the quenched samples were identified by microscopy. The solubility limit of iron oxide in CaO is strongly dependent …
The Effect Of Cathodic Protection On The Stress Corrosion Characteristics Of 300m Low Alloy Steel, John Pechonick
The Effect Of Cathodic Protection On The Stress Corrosion Characteristics Of 300m Low Alloy Steel, John Pechonick
Masters Theses
"The objective of this investigation was to determine if stress corrosion failure of 300M steel is accelerated by the application of cathodic protection. Testing was conducted on notch tensile specimens that were coated with vacuum cadmium, electroplated cadmium, and vacuum aluminum. All specimens were stressed and placed in an aqueous sodium chloride environment. The failure times for the specimens were monitored and graphs were drawn which characterized the stress corrosion resistance of 300M steel and the cathodic protection systems. Fractography techniques were used to study the failure surfaces to determine the type of failure mechanism. The results of this thesis …
Quenching Defects In Aluminum Plus Ten Atomic Per Cent Zinc, James Thomas Grider
Quenching Defects In Aluminum Plus Ten Atomic Per Cent Zinc, James Thomas Grider
Masters Theses
"This study was undertaken to resolve the conflict which has recently arisen as to the as-quenched microstructure in the Al-Zn system as revealed by thin film transmission electron microscopy. The composition range of most active study has been that from 5 to 15 atomic per cent Zn in superpurity AL. Consequently a composition of 10 atomic per cent Zn was chosen for this study. There are no discontinuties in the phase diagram in this composition range which would influence the above choice. It exists as a single phase solid solution at high temperatures and as a two phase alloy at …
The Design Of A High Temperature Thermoelectric Generator Element Using Silicon Carbide, John Talmage Barrow Jr.
The Design Of A High Temperature Thermoelectric Generator Element Using Silicon Carbide, John Talmage Barrow Jr.
Masters Theses
"This report presents the design of an optimum, high temperature silicon carbide thermoelectric generator element. The analytical efforts have been divided into three basic parts, the development of the theory, the accumulation of the data, and the optimization of the design. The first step in the theory development was the derivation of accurate design equations. With this done, the design philosophy and computer program were constructed, the latter utilizing a subroutine to contain the design equations. The data was obtained from a survey of many references and, for the most part, was found to be inexact, requiring the consideration of …
Effects Of Flat And Elongated Particles Upon Properties Of Mixtures Containing Glass Aggregates, John Dean Doyle
Effects Of Flat And Elongated Particles Upon Properties Of Mixtures Containing Glass Aggregates, John Dean Doyle
Masters Theses
"As a possible solution for the rapidly proliferating problem of waste glass disposal in the United States, glass is being considered for use as aggregate in bituminous concrete mixtures. Crushed waste glass particles, and crushed bottle glass particles in particular, are more angular, much smoother, and contain a higher percentage of flat and/or elongated particles than conventional rock aggregate particles. Because of the differences in shape and surface texture, glass aggregate may require different gradations than those found suitable for conventional rock aggregate. Objectives of this research were to determine gradations which result in maximum density for aggregates consisting entirely, …
Interactions Between Selected Pigment Producing Bacteria Isolated From Sewage, Leslie Alexander Lakie
Interactions Between Selected Pigment Producing Bacteria Isolated From Sewage, Leslie Alexander Lakie
Masters Theses
"Pigmented bacteria have been of interest to the microbiologist for several years. The pigmented organisms in sewage have been known to gain predominance, but no investigations have been made to determine whether the pigment assists the organism in gaining predominance. During this study a number of bacteria which produced a water soluble pigment were isolated from sewage. These bacteria were grown in shaken flasks using tryptone Glucose extract broth as a medium. Growth studies of the bacteria in pure and mixed culture were performed to determine if the pigment could affect another bacteria's growth. Studies were also performed using the …
Final Sintering Of Cr₂O₃ With Minor Additions Of Mgo And Sintering Of Mgo With Minor Additions Of Cr₂O₃, Gordon E. Jungquist
Final Sintering Of Cr₂O₃ With Minor Additions Of Mgo And Sintering Of Mgo With Minor Additions Of Cr₂O₃, Gordon E. Jungquist
Masters Theses
"The effect of oxygen activity on the sintering of Cr₂O₃ with minor additions of MgO, and of MgO with minor additions of Cr₂O₃ at 1600ºC was investigated. A peak density (99.4% of theoretical) was obtained for high purity Cr₂O₃ by maintaining the equilibrium oxygen partial pressure needed to maintain the Cr₂O₃ phase. The addition of 0.1 wt. % MgO increased the sintered density at the same oxygen pressure to 99.8%. Further MgO additions decreased the density. The density of pure MgO was independent of the PO₂ over the range investigated. Addition of Cr₂O₃ to MgO decreased the density at …
A Study Of Early-Late Type S0-Pcm Signal Bit Synchronizers, Kuang-Cheng Hu
A Study Of Early-Late Type S0-Pcm Signal Bit Synchronizers, Kuang-Cheng Hu
Masters Theses
"The steady-state phase noise performances of an absolute value type and a squaring loop type of early-late gate S0-PCM signal bit synchronizers are developed using the Fokker-Planck method. The results are compared on the basis of the performance of two configurations with equal loop bandwidth at each input signal-to-noise ratio Rs. The probabilities of bit-detection error of the two configurations are compared. These comparisons are made as a function of Rs. The absolute value type of early-late gate S0-PCM signal bit synchronizater yields better performance than that of the squaring loop type of early-late gate S0-PCM …
Alkali Mobility And Mechanical Relaxation In Mixed-Alkali Silicate Glasses, James W. Fleming Jr.
Alkali Mobility And Mechanical Relaxation In Mixed-Alkali Silicate Glasses, James W. Fleming Jr.
Masters Theses
"Internal friction and sodium and potassium self-diffusion coefficients for (1-X)Na₂O · XK₂O· 3SiO₂ glasses were measured. Alkali diffusion was measured between 300 and 500ºC using radioactive isotopes and a thin-sectioning technique. Internal friction was measured from room temperature to 500ºC, 0.1 to 2000 Hz. Comparison between alkali diffusion and internal friction data for Na-K glasses with those for other mixed-alkali glasses shows that the mixed-alkali peak is related to alkali mobility. It is concluded that the mechanism for mixed-alkali internal friction is a cooperative rearrangement of dissimilar alkali ions, with the slower moving ion controlling the rate of reorientation"--Abstract, page …
Reservoir Design: Simulation Techniques, Larry W. Mays
Reservoir Design: Simulation Techniques, Larry W. Mays
Masters Theses
"A simulation model is developed to aid in the analysis of small dams to reduce the possibility of inadequate spillway designs. Basic assumptions concerning the geometric aspects of the natural reservoir are made to develop the model which is based upon describing the timing and magnitude of a design flood passing through a reservoir. Simulation equations are derived from the basic continuity equation and describe reservoir outflow and storage as functions of reservoir depth. Newton's Iteration Technique is utilized to solve the simulation equations for the reservoir depth. The resulting simulation model determines an optimum size auxiliary spillway having a …
A Study Of The Effects Of Mixing On The Accelerated Anaerobic Digestion Of Concentrated Municipal Sludges, Victor Darryl Orr
A Study Of The Effects Of Mixing On The Accelerated Anaerobic Digestion Of Concentrated Municipal Sludges, Victor Darryl Orr
Masters Theses
"Most domestic sewage treatment plants today practice anaerobic digestion of sludge. The purpose of this investigation was to determine if thorough mechanical mixing of concentrated sludge would improve its digestion. The simulated digesters consisted of six 1 gallon anaerobic reactors which were operated in the laboratory for 78 days. The contents of three digesters were continually mixed and their responses were compared with those of the similarly loaded remaining three unmixed units. Raw sludge with solids concentrations of 7.5, 15 and 30 per cent was digested for detention periods of 30, 15 and 7.5 days at 33º C. Various analyses …
The Effect Of Solvents On The Desorption Of Phenol From Carbon In A Water Free System, William W. Knickmeyer
The Effect Of Solvents On The Desorption Of Phenol From Carbon In A Water Free System, William W. Knickmeyer
Masters Theses
"The desorption of phenol from active carbon was studied using a continuous flow desorber. The system used was nearly water free to reduce water-phenol interactions. The ten solvents used in this study exhibited a wide difference in their desorption capabilities. An attempt to correlate the desorption data with the physical properties of phenol and solvents, in addition to regular solution theory, proved unsuccessful. A thermodynamic approach using the linear free energy-enthalpy relationship produced a general trend by using the heat of solution for phenol in solution and a reasonable correlation using the heat of formation of the phenol-solvent hydrogen bond …
Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Pt In Acid Sulfate Solutions, Howard Ho-Wei Jiang
Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Pt In Acid Sulfate Solutions, Howard Ho-Wei Jiang
Masters Theses
"The anodic oxidation of EDTA was studied in acid sulfate solutions on platinized-Pt at 25ºC. Polarization relationships were obtained for the EDTA concentration range 3. 42 x 10⁻⁵ to 3. 42 x 10⁻³ M and pH range 0. 35 to 3. 80. Numerous reaction products were identified that indicated a sequential removal of acetate groups from the EDTA, each by an initial decarboxylation followed by a reverse Schiff-type reaction, that produced formaldehyde and the corresponding amine. A reaction sequence which correlated the experimental data involved Frumkin-type adsorption of the EDTA species through an unionized acetate group followed by a rate-determining …
Electrolytic Reduction Of Zinc From Acidic Sulfate Solutions, Kenneth Dale Gielow
Electrolytic Reduction Of Zinc From Acidic Sulfate Solutions, Kenneth Dale Gielow
Masters Theses
"Cathode polarization curves were obtained for the electrodeposition of zinc from sulfate solutions with pH 2 and zinc concentrations of 10.0, 40.0, 80.0, and 100.0 gpl zinc. Both pure zinc and pure aluminum were used as cathodes with some difference in results noted. The effect of animal glue additions of 0.01, 0.10, and 0.50 gpl of solution on the cathodic polarization curves and the resulting deposit morphologies were determined. These glue additions correspond to 0.20, 2.0, and 10.0 pounds of glue per ton of zinc deposited, respectively. The slope of the Tafel region of the polarization curves was found to …
A Study Of Radiative Heat Transfer From A Spherical Layer, Hakimuddin Kalimuddin Khalil
A Study Of Radiative Heat Transfer From A Spherical Layer, Hakimuddin Kalimuddin Khalil
Masters Theses
"The problem of radiative heat transfer from a spherical layer of absorbing-emitting gas has been studied. First, the medium is assumed to be gray and then nongray. A thorough survey of literature from fields other than heat transfer, such as astrophysics and neutron transport has been made to stimulate further interest in this important area. To gain some insight into the effect of various parameters on the heat transfer, simple physical situations involving isothermal medium are considered. Comparison of the results obtained for the flux from the spherical and planar layers reveal that the curvature becomes increasingly important as the …
A Statistical Hydrologic Simulation Model, Ronald L. Wycoff
A Statistical Hydrologic Simulation Model, Ronald L. Wycoff
Masters Theses
"Simulation of a physical system requires knowledge of all components of the system and their interactions. A probabilistic simulation model of a hydrologic system is developed from short term continuous, sychronized rainfall-runoff records. The individual components of the system area the time between and duration of storms, the depth of rain occurring in each time period of the storm, precipitation excess relations, and the watersheds unit hydrograph. The available data is used to define or develop the probabilistic models involved. The only nonprobabilistic model employed is the watersheds unit hydrograph. It is found that the time between and duration of …
Sediment Properties And Depositional Environment Of The Minnelusa Formation (Permo-Pennsylvanian), Northern Black Hills, South Dakota And Wyoming, El-Magtuf Taleb Taleb
Sediment Properties And Depositional Environment Of The Minnelusa Formation (Permo-Pennsylvanian), Northern Black Hills, South Dakota And Wyoming, El-Magtuf Taleb Taleb
Masters Theses
"Permo-Pennsylvanian sedimentary rocks of the Minnelusa Formation of the Black Hills uplift, South Dakota and Wyoming, can be divided into upper, middle and lower divisions on the basis of lithology. The upper portion of 150 to 200 feet consists of gray and yellow sandstone, with some carbonates and shales in some sections. The middle portion, about 200 to 220 feet thick consists of gray and red sandstone with carbonate members including the prominent dolomite member at the base; some of the carbonates are cherty. The lower portion, 20 to 60 feet thick, consists of pink sandstone, arenaceous dolomite and thin …
A Study Of The Void-Strengthening Of Aluminum And Its Nature, Purushottam G. Manusmare
A Study Of The Void-Strengthening Of Aluminum And Its Nature, Purushottam G. Manusmare
Masters Theses
"Strengthening of aluminum by formation of the voids and the nature of resultant strengthening, viz., the temperature and the strain rate dependence of its yield strength were studied. Aluminum wires with 99.999% purity and of 3.1 mm diameter were quenched and heat treated to form voids of the approximate density 10¹³-10¹⁴ voids/cm³ and were tested for their yield strength. Voids in selected samples were observed by transmission electron microscopy using the Hitachi HU-11A microscope. The yield strength of the void strengthened samples was measured at various temperatures from 77ºK to 593ºK using two strain rates, 3.33 x 10⁻²/sec and 1.67 …
Calculation Of Eddy Current Loss Of A Disc, Kou Quen Chang
Calculation Of Eddy Current Loss Of A Disc, Kou Quen Chang
Masters Theses
"A method is presented to calculate the eddy current losses of a uniform disc with an opening in the center and excited by a circular current loopage First, the disc is subdivided into smaller concentric rings, then the self-inductances, the mutual inductances between these smaller rings, the mutual inductances between the excitation coil and the smaller rings, and the resistance of the rings are calculated. Next, the eddy current flowing in each ring is obtained by solving a complex matrix equation of the form [X] [I] = [V] where X is the impedance matrix, I is the eddy current matrix, …
Two Component Heat Pipe, Surapol Chandsawangbhuvana
Two Component Heat Pipe, Surapol Chandsawangbhuvana
Masters Theses
"A two component heat pipe with water and ethanol as the working fluid was investigated at different angles of inclination and various ethanol concentration for two power loads. The heat pipe was 15 inches long and 0.75 inches in diameter with a 100 mesh stainless steel screen wick. The wall and the vapor temperatures were measured at different stations along the length of the heat pipe by copper-constantan thermocouples. The results were used to evaluate an existing model which includes the constraint of thermodynamic phase equilibrium of the solution on the governing equations. Based on the measured pressure and temperature …
Radiant Interchange In A Non-Isothermal Rectangular Cavity, Tilak Raj Sawheny
Radiant Interchange In A Non-Isothermal Rectangular Cavity, Tilak Raj Sawheny
Masters Theses
"Radiant interchange between non-isothermal, gray diffuse surfaces with non-uniform radiosity has been determined for a rectangular cavity. Temperature distribution and heat flux as thermal specifications for the parallel surfaces of the cavity have been considered separately. Ambarzumian's method has been used for the first time to solve a radiant interchange problem. According to the method, the integral equation for the radiosity is first transformed into an integro-differential equation and then into a system of ordinary differential equations. Initial conditions required to solve the differential equations are the H-functions. The H-functions represent the radiosity at the edge of the cavity for …
The Use Of Scattering Parameters In Amplifier Design, Yousef Neman-Ebrahim
The Use Of Scattering Parameters In Amplifier Design, Yousef Neman-Ebrahim
Masters Theses
"The scattering-parameter formulation of an active two-port device is developed from the compensation theorem. The use of scattering parameters in graphical developments of forward operating power gain and tunability is considered in detail. Finally, two design examples show the application of the graphical procedures"--Abstract, page ii.
Digested Sludge Dewatering On Drying Beds Under Controlled Environmental Conditions, Daniel James Harris
Digested Sludge Dewatering On Drying Beds Under Controlled Environmental Conditions, Daniel James Harris
Masters Theses
"The dewatering characteristics of anaerobically digested primary and activated sludge were investigated under eight selected combinations of laboratory controlled air temperature and relative humidity using three open, drained model beds, as well as a closed, drained and an open, nondrained bed. The evaporation rate from a free water surface was also determined. Moisture content, drainage, evaporative weight loss, and sludge surface recession were measured and recorded periodically throughout the two week period of each of the eight experiments. Relationships were shown to exist between sludge moisture content, evaporation rate from a free water surface, and the parameters 6T (the difference …
Evaporation And Condensation Of Zinc, Shailesh Bhanuprasad Vora
Evaporation And Condensation Of Zinc, Shailesh Bhanuprasad Vora
Masters Theses
"Evaporation rates of liquid zinc were determined experimentally within the temperature range of 450º C to 575º C and at argon pressures ranging from 730mm Hg to 130mm Hg. Extrapolated values of these rates are found to be consistent with the previously reported rates obtained by St. Clair and Spendlove at lower pressures. Between 100 microns and one atmosphere pressure rates of evaporation seem to vary according to an equation of the form W = APᴮ, where Pis pressure and, A and B are constants. Similar experiments were performed with brass powders in atmospheres of argon and helium at temperatures …
Low Frequency Lumped Element Directional Couplers, Constantine Rodolph Jenkins
Low Frequency Lumped Element Directional Couplers, Constantine Rodolph Jenkins
Masters Theses
"Lumped element directional couplers are desirable at frequencies below the VHF range because they eliminate the large physical size necessary for the distributed element directional couplers. The purpose of this work is to describe the theory and design of such low frequency lumped element directional couplers. A model for the coupler is developed and the equations which describe it are derived. Scattering matrices for one and two section couplers are obtained. Computer solutions for three section couplers are presented. Experimental results for one, two, and three section couplers are presented and comparison with theory are made. Comparisons of theoretical and …
Feed Drive Design For Numerically Controlled Machine Tools, Subash Bhatia
Feed Drive Design For Numerically Controlled Machine Tools, Subash Bhatia
Masters Theses
"The various types of feed drive control systems used in numerical control of machine tools have been broadly classified. Further a step by step design has been presented for the feed drive of a numerical contouring control milling machine. The aim has been to develop a consistent strategy for tackling a variety of such problems. Consequently stress has been laid on principles and not on design figures"--Abstract, page ii.
Frequency Division Using Cascaded Phase-Locked Loops, Curtis B. Abshier
Frequency Division Using Cascaded Phase-Locked Loops, Curtis B. Abshier
Masters Theses
"In many practical communication systems it is necessary to generate phase coherent subharmonics of an input tone. A useful system for accomplishing this task is a system of phase-locked loops in cascade. It is shown that when the feed-forward function is matched, the phase error of the second loop is zero. Analytical analysis and computer simulation prove that the minimum time to achieve phase-lock is obtained when the feed-forward function is matched. Under this condition, necessary design parameters are determined with ease"--Abstract, page i.
Design Of A Quadrature Envelope And Correlating Receiver, Clinton Harold Moor
Design Of A Quadrature Envelope And Correlating Receiver, Clinton Harold Moor
Masters Theses
"A receiver design analysis and rationale is presented. The receiver is capable of performing in an instrumentation role for propagation experiments conducted in the field. The data gathered during the field tests will be used to determine the complex impulse response of the ground-to-ground communications channel and to evaluate the performance of a candidate ranging waveform in this channel. The receiver is capable of operation in either the propagation mode or the ranging mode and each mode of operation can be performed on either a UHF band frequency or an L-Band frequency. During the propagation mode the receiver serves as …
An Analysis Of Solar Noise Outbursts And Their Application To Space Communication, Marion Francis Moen
An Analysis Of Solar Noise Outbursts And Their Application To Space Communication, Marion Francis Moen
Masters Theses
"A relationship between sunspot activity, solar flare activity and noise outbursts is presented. Five different types of interference radiation in the 10MHz to 30,000 MHz frequency band are discussed. Data obtained by solar radio astronomy are analyzed to determine the extent of solar noise outbursts as a function of sunspot activity. An application of the burst data to future space communication is given"--Abstract, page ii.
Variable-Threshold-Mixed-Weight Threshold Element, Cheng-Chung Liu
Variable-Threshold-Mixed-Weight Threshold Element, Cheng-Chung Liu
Masters Theses
"A threshold element (TE) is a mathematical model of a class of logic gates. The desirability of a threshold element in the application of digital systems stems from its richness of logic power and its relative economy. On the other hand, the tighter tolerences required by the threshold logic element as compared to conventional logic gates have prevented them from being utilized extensively. The purpose of this thesis is to propose a versatile threshold element having high noise immunity and loose tolerance requirement. The proposed TE which has variable threshold and mixed weight capability uses current switching to enhance noise …