Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Theses/Dissertations

Discipline
Institution
Keyword
Publication Year
Publication
File Type

Articles 73801 - 73830 of 77382

Full-Text Articles in Engineering

A Systematic Study Of Instrument Variables Upon The Accuracy Of Microprobe Analysis, R. A. Parr Jan 1970

A Systematic Study Of Instrument Variables Upon The Accuracy Of Microprobe Analysis, R. A. Parr

Masters Theses

"The purpose of this investigation was to study the effect of instrument parameter changes upon X-ray intensity measurements of the copper-manganese system. The parameters utilized in this study included: (1) polished, contaminated, and 600 grit surfaces ; (2) constant sample current and constant beam current modes; and (3) 15 KV, 20 KV, and 25 KV accelerating potentials. Inspection of the data disclosed three interesting points: (1) copper and manganese X-ray intensity measurements appear to be a linear function of composition in the 15 KV through 25 KV accelerating potential range; (2) electron backscatter measurements consistently show in a limited range …

Go to article

An Sem Surface Study Of Nucleate Pool Boiling Heat Transfer To Saturated Liquid Nitrogen Reduced Pressures From 0.1 To 0.9, David Virgil Porchey Jan 1970

An Sem Surface Study Of Nucleate Pool Boiling Heat Transfer To Saturated Liquid Nitrogen Reduced Pressures From 0.1 To 0.9, David Virgil Porchey

Doctoral Dissertations

"This study constituted an examination of both nucleate boiling and maximum heat flux characteristics of liquid nitrogen boiling from characterized surfaces. Several textures of gold plated copper surfaces were studied in addition to silver and silver oxide surfaces. Data were taken over a wide range of reduced pressures. All surfaces were examined using a Scanning Electron Microscope (SEM). Data and micrograph comparison revealed that both surface chemistry and surface roughness affect the nucleate boiling characteristics of liquid nitrogen. These effects are separated from each other showing that nucleate boiling is a function of both surface chemistry and topography. Surface roughness …

Go to article

Abandoned Automobiles :A Case History Of Land Pollution, Robert William Arden Jan 1970

Abandoned Automobiles :A Case History Of Land Pollution, Robert William Arden

Masters Theses

"A study has been made of the abandoned automobile problem as it now exists throughout the United States with particular emphasis on the problem in the Saint Louis area. The primary goal of this study was to determine those factors which most influence the collection and disposal of derelict vehicles. The problem was examined in the following major areas: (1) The history of the problem in the Saint Louis area and the various attempts made to correct it, (2) the various businesses directly involved with the disposal of junk automobiles, namely, the auto wreckers and the scrap processors, and (3) …

Go to article

The Closed Cycle-External Combustion Engine And Air Pollution, Galen Lee Pearson Jan 1970

The Closed Cycle-External Combustion Engine And Air Pollution, Galen Lee Pearson

Masters Theses

"The impact of the internal combustion engine on the air pollution problem in this country was presented and alternative propulsion systems for the land transportation vehicle were investigated. The potential characteristics of the more promising closed cycle-external combustion engine concepts were established and discussed. The closed thermodynamic power cycles analyzed include the Rankine, Stirling, and Feher supercritical cycles. Thermodynamic property data on eighteen candidate working fluids for the Rankine and Feher supercritical power cycles have been assembled and were presented in a utilizable form. The thermal efficiency (ratio of the net work out to the heat input) and the many …

Go to article

The Anodic Dissolution Of Molybdenum In Acidic Nitrate Solutions, Kuan-Hsiung Hoh Jan 1970

The Anodic Dissolution Of Molybdenum In Acidic Nitrate Solutions, Kuan-Hsiung Hoh

Masters Theses

"The anodic dissolution of molybdenum in 1.0 N HNO₃ (pH = 0.3) , 0.1 N HNO₃-0.9 N KNO₃ (pH = 1.2), and 0.01 N HNO₃ -0.99 N KNO₃ (pH = 2.1) was investigated. The following conclusions were possible: 1. Mo is in general electrochemically oxidized to the Mo-VI state during anodic dissolution. 2. The resultant ions in solution are HMOO⁻₄. 3. The Mo surface in aqueous solutions is covered with an oxide whose approximate composition is Mo₂O₅. 4. The polarization curves have a linear Tafel region at potentials slightly above the rest potential. 5. There is no significant effect of …

Go to article

An Analysis Of A Synchronization Scheme For 180° Biphase Modulated Signals, James Joseph Spence Jan 1970

An Analysis Of A Synchronization Scheme For 180° Biphase Modulated Signals, James Joseph Spence

Masters Theses

"The problem of analyzing a synchronization system for demodulation of 180° biphase modulated signals is considered in this thesis. The system considered utilizes the so-called squaring loop technique. Techniques derived from the theory of Markov processes are utilized in the analysis of the system. In particular the "fluctuation equation" approach for non-Markovian processes is used. After the analysis of the system is performed, an expression fro the bit error probability is obtained from knowledge of the phase error density function"--Abstract, Page ii.

Go to article

Measurement Of Thermal Accommodation Coefficients Of Steel Surfaces, Wing On Ho Jan 1970

Measurement Of Thermal Accommodation Coefficients Of Steel Surfaces, Wing On Ho

Masters Theses

"The thermal accommodation coefficient plays an important role in low density thermal energy transfer measurement. The object of this investigation was to measure the thermal energy transfer between a heated test surface and a water cooled reference surface (flat black lacquer) consisting of two infinite concentric cylinders separated by dry air. Two machined and sanded steel cylinders with mean surface roughnesses of 25 microinches and 7.5 microinches were used as the test surfaces . Measurements were made in the pressure range of 1.2 x 10⁻⁶ mm Hg. to 1.8 x 10⁻⁶ mm Hg. and temperature range for test cylinders of …

Go to article

Analysis Of Parking Conditions At The University Of Missouri - Rolla And Their Comparison To Other Universities, Richard Francis Rankin Jan 1970

Analysis Of Parking Conditions At The University Of Missouri - Rolla And Their Comparison To Other Universities, Richard Francis Rankin

Masters Theses

"The existing parking facilities at the University of Missouri - Rolla are presently inadequate and parking demand will continue to increase in the coming years. Factual study of existing conditions by means of physical vehicle counts indicate that operational efficiency can be increased as a method of reducing the parking shortage. It was determined, by a faculty and staff questionnaire, that the automobile was not greatly required in order to carry out university business. A faculty residence density study indicated that the majority of the faculty members live farther than 7/10 of a mile from the campus. Present methods of …

Go to article

Z-Form Solution Of Non-Linear Differential Equations, Allen Joseph Rushing Jan 1970

Z-Form Solution Of Non-Linear Differential Equations, Allen Joseph Rushing

Masters Theses

"The "Z-Forms" developed by Boxer and Thaler from Z-Transform theory are reviewed. Iteration is shown to increase accuracy when Z-Forms are used to obtain numerical solutions to some non-linear differential equations. Machine results are presented for example problems. Error estimates and convergence conditions are discussed. The method is usable only when 2- or 3-digit accuracy is acceptable. For some classes of equations the Z-Form method compares favorably to other numerical methods in time required to set up the problem and in machine time required for solution--Abstract, Page ii.

Go to article

Integrating An Oscilloscope Into A General Purpose Automatic Test System, William Charles Bauer Jan 1970

Integrating An Oscilloscope Into A General Purpose Automatic Test System, William Charles Bauer

Masters Theses

"The General Purpose Automatic Test System was developed for the Air Force as a system to automatically test and fault isolate an electronic unit under test. The Test System is a building block concept and this paper developed the hardware and programming software necessary to integrate an oscilloscope into the system. A Tektronix Type 564 oscilloscope with a Tektronix Type 3A5 Programmable Amplifier and a Tektronix Type 3B5 Programmable Time Base was used. A prototype of the digital and analog interface between the Test System and the Tektronix System was built and demonstrated. The Oscilloscope Building Block displays waveforms only …

Go to article

A Study Of The Effects Of Pressure-Induced Viscosity Changes On The Fluid Flow Characteristics In A Circular Tube, Robert Charles Weber Jan 1970

A Study Of The Effects Of Pressure-Induced Viscosity Changes On The Fluid Flow Characteristics In A Circular Tube, Robert Charles Weber

Masters Theses

"A method of determining the response of fluids under high pressure to quick-release into the atmosphere is presented in this report. The analytical efforts have been formulated into two parts, a closed-form solution and a numerical analysis. By assuming constant viscosity of the fluid a closed-form solution was obtained. The assumption of constant viscosity was found to be acceptable for the test fluids up to an initial pressure of approximately 10,000 psi. A numerical analysis became necessary for initial pressures over 10,000 psi, where the variable viscosity of the fluid had to be considered. The experimental work was conducted by …

Go to article

Metallographic Study Of Phase Changes In Heat Treated Ductile Iron, Mahendra Vadilal Desai Jan 1970

Metallographic Study Of Phase Changes In Heat Treated Ductile Iron, Mahendra Vadilal Desai

Masters Theses

"Continuous cast ductile iron samples were hardened. It was found that carbide dissolved in the austenite faster than graphite and that this material requires higher austenitizing temperatures and longer austenitizing time than steels. Tempered microstructures were affected by the prior austenitizing treatment and it appeared that the amount of carbon dissolved in the austenite determined the tempered microstructure. Several attempts to determine the austenite grain size indicated that it is not as easy to determine in ductile iron as in steels. Two techniques, heat etching and an isothermal transformation method, were found to reveal prior austenite grain size. It was …

Go to article

Oxygen Uptake By The Benthal Sludge Of A Waste Stabilization Pond, Edward Landon Niedringhaus Jan 1970

Oxygen Uptake By The Benthal Sludge Of A Waste Stabilization Pond, Edward Landon Niedringhaus

Masters Theses

"This thesis describes the laboratory evaluation of the benthal sludge oxygen uptake of a 6.7 acre waste stabilization pond which has served a city of 2,400 population for a period of seven years. Special emphasis is directed toward the explanation of laboratory techniques developed for this study to measure the oxygen uptake rate. The effects on oxygen consumption of temperature, nature of sludge, initial oxygen tension, and sludge consolidation are discussed. Benthal sludge samples were taken from three locations in the pond. Oxygen consumption studies were conducted in a specially designed plastic cylinder which included a novel magnetic mixing system. …

Go to article

The Anodic Oxidation Of Oxalic Acid On Au, Steven C. Mueller Jan 1970

The Anodic Oxidation Of Oxalic Acid On Au, Steven C. Mueller

Masters Theses

"The anodic oxidation of oxalic acid on Au has been studied at 80°C in aqueous media. The reaction rate was measured as a function of potential, oxalic acid concentration, pH, and temperature in H₂SO₄-K₂SO₄-KOH solutions of unit ionic strength. The oxalic acid was oxidized only in acidic media. The oxidation to CO₂ was essentially complete. A first order dependence of the rate on both pH and undissociated oxalic acid was found. A mechanism is proposed in which the first decarboxylation is the rate determining step"--Abstract, page 1.

Go to article

A Study Of The Design And Construction Of A Full Scale Aircraft Component Demonstration Fatigue Test, Stephen Andrew Wright Jan 1970

A Study Of The Design And Construction Of A Full Scale Aircraft Component Demonstration Fatigue Test, Stephen Andrew Wright

Masters Theses

"The objective of this project was to design and build a full scale demonstration fatigue test for a Piper Aztec stabilator. A general discussion of the construction is included in this report. The Fourier series method of the aerodynamic theory of spanwise loading was used to determine the load distribution. The results show a close relationship with data furnished by Piper Aircraft Corporation. Fatigue theory is discussed in order to provide background for fatigue testing. The test specimen, methods and procedures of testing, known loading methods and systems, safety, etc., are discussed. Federal requirements for regulating and testing of aircraft …

Go to article

Spheroidization In Tool Steels, Sharad Gajanan Bankar Jan 1970

Spheroidization In Tool Steels, Sharad Gajanan Bankar

Masters Theses

"A carbon steel, W1, and four other alloy tool steels, namely, A2, H13, D3, and M2, were spheroidized by five different procedures. Any modification made in the treatments for an individual steel were suggested by the results obtained with these five procedures. The hardnesses and microstructures obtained were compared with steel samples annealed at a tool steel mill. The response given by different steels to various methods of spheroidization was studied. It was found that A2, W1, and D3 steels responded the best to the cycling method whereas the best response to the isothermal annealing was given by H13 and …

Go to article

On-Line Digital Computer Decoding Of Radio Teletype, Julio Alberto Spiegel Jan 1970

On-Line Digital Computer Decoding Of Radio Teletype, Julio Alberto Spiegel

Masters Theses

"Digital computer data processing is one of the newest and fastest growing technologies. The large amount of data that can be processed is practically beyond the limit of human possibilities when available time, cost and reliability of results are taken into consideration. The use of on-line digital computer data processing to decode Radio Teletype is investigated in this thesis. The first part of this thesis considers existing teletype systems and related systems, such as Pulse Code Modulation, pointing out the differences between synchronous and asynchronous codes. The most critical step in decoding Radio Teletype is synchronization, since Radio Teletype makes …

Go to article

The Effect Of Solvents On The Desorption Of Phenol From Carbon, Robert Harold Pahl Jan 1970

The Effect Of Solvents On The Desorption Of Phenol From Carbon, Robert Harold Pahl

Masters Theses

"The desorption of phenol from active carbon was studied using cyclic and continuous flow desorbers. A wide difference in desorption capabilities was shown among nine solvents. The system employed was complex, with water being present in addition to phenol on the carbon. An attempt to correlate the desorption data with the physical properties of the phenol and solvent and Regular Solution theory are presented. A thermodynamic approach using the linear free energy-enthalpy relationship produced an apparently good correlation of the heat of formation of the phenol-solvent hydrogen bond with the desorption data. This indicates that the desorption of the phenol …

Go to article

Investigations Of Several Variables In The Dwight-Lloyd Mcwane Ironmaking Process, James Orlan Hood Jr. Jan 1970

Investigations Of Several Variables In The Dwight-Lloyd Mcwane Ironmaking Process, James Orlan Hood Jr.

Masters Theses

"The Dwight- Lloyd McWane Ironmaking Process (D-LM) is the first commercial process of its particular type and one of the few commercial processes involving prereduction of iron ore in existence today. This presentation reviews some promising ironmaking processes which involve iron ore prereduction, with special attention being given the D-LM process. Although the D-LM process is continuous from iron ore to high quality molten cast iron, the research and discussion herein is limited to principal variables involved in the production of high quality carbonized pellets in the prereduction phase of the operation. The variables of process temperature and pellet carbon …

Go to article

Recovery Of Trace Organic Pollutants By Solvent Extraction And Freeze Concentration, William Chih-Wen Chang Jan 1970

Recovery Of Trace Organic Pollutants By Solvent Extraction And Freeze Concentration, William Chih-Wen Chang

Masters Theses

"The objective of this investigation was to evaluate the use of batch type solvent extraction and freeze concentration in recovering trace organic pollutants from water. The work was performed using a simplified water system containing known concentrations of phenol, and natural water systems collected from three sources (Meramec Spring, Gasconade River near Jerome, and Missouri River in Jefferson City) with different levels of pollution. The simplified water system was used to evaluate the effect of the number of extractions, solvent to sample ratio, extraction time, initial organic concentration, pH, and turbidity on solvent extraction; and the effect of volumetric concentration …

Go to article

Optumr A Digital Computer Program To Cost Optimize A District Heat Piping Network To Remove Waste Heat From Nuclear Power Reactors, James Richard Hendricks Jan 1970

Optumr A Digital Computer Program To Cost Optimize A District Heat Piping Network To Remove Waste Heat From Nuclear Power Reactors, James Richard Hendricks

Masters Theses

"The thermal pollution problem of a nuclear reactor electrical generating facility can be eliminated if an economical, productive use for the waste heat can be found. The computer program presented here is designed to investigate the economic feasibility of utilizing this waste heat to heat buildings. The program optimizes a district heating network using the reactor's rejected heat and performs a comparative analysis with a selected conventional heat rejection system. The results indicate that the system is feasible only if the reactor can be sited relatively close (5 miles) to an urban center. Increasing national concern regarding thermal pollution and …

Go to article

Light Scattering As A Means Of Probing Particulate Systems, Arwind Krishna Gore Jan 1970

Light Scattering As A Means Of Probing Particulate Systems, Arwind Krishna Gore

Masters Theses

"The primary purpose of this investigation is to provide basic data needed in determining the size distribution of water-droplets in cloud chambers, sprays, dust clouds, etc. A critique of the classical Mie scattering theory is made to evaluate the influence of the properties such as size, shape and refractive index and of the particulate concentration on the scattering functions. Using He-Ne gas laser radiation of 6328 Å wavelength as the source, the angular intensity functions are tabulated for water-drops up to 20 microns in diameter, dispersed in air at 25ºC. A size interval of 0.2 microns and an angular interval …

Go to article

A Study Of The Effects Of Added Solid-Liquid Interfacial Area On The Stabilization Characteristics Of Simulated Wastewater Stabilization Lagoons, Gary Lee Gaines Jan 1970

A Study Of The Effects Of Added Solid-Liquid Interfacial Area On The Stabilization Characteristics Of Simulated Wastewater Stabilization Lagoons, Gary Lee Gaines

Masters Theses

"Wastewater stabilization lagoons have recently become a popular and efficient method of sewage stabilization in many parts of the country. The purpose of this investigation was to determine the effect of added solid-liquid interfacial area on the treatment capabilities of simulated wastewater stabilization lagoons. The simulated lagoons consisted of six -15 gallon aquariums which were operated in the laboratory. The solid-liquid interfacial area was increased in four of these lagoons by suspending plastic panels in the aquariums. The lagoons were operated for a period of approximately two and a half months using dehydrated milk as a simulated waste substrate. During …

Go to article

Mutually Dependent Heat And Mass Transfer In Laminar Tube Flow, Gary Alfred Scheffel Jan 1970

Mutually Dependent Heat And Mass Transfer In Laminar Tube Flow, Gary Alfred Scheffel

Masters Theses

"An investigation is performed of the mutually dependent heat and mass transfer in laminar and hydrodynamically fully developed gas flow in a tube. Sublimation of mass occurs at the tube wall so that heat and mass transfer take place between the wall and the flowing gas stream. The wall of the tube is thermally insulated from the external environment with the result that the heat of sublimation is supplied by convective transport from the gas. The solution of this problem requires the simultaneous consideration of the energy and diffusion equations, with coupling provided by the boundary conditions. Mathematical expressions are …

Go to article

Removal Of Phosphate By Sorption On Activated Alumina, Checkman Michael Yue Jan 1970

Removal Of Phosphate By Sorption On Activated Alumina, Checkman Michael Yue

Masters Theses

"The purpose of this investigation was to study the removal of phosphorus from waste water by sorption on activated alumina, and determine the capacity of the alumina to sorb phosphates in the presence of other ions, the effect of the influent flow rate and phosphorus concentration on the efficiency of the process, and the feasibility of regeneration of the used alumina. The studies were conducted using deionized and tap water to which inorganic phosphate had been added, and secondary effluent from bench-scale activated sludge units. They involved batch tests employing three types of activated alumina, ALCOA XM (minus 325 mesh), …

Go to article

A Comparative Study Of Experimental And Computed Compressibility Factors Of Ethane-Carbon Dioxide-Nitrogen System, Brij Raj Misra Jan 1970

A Comparative Study Of Experimental And Computed Compressibility Factors Of Ethane-Carbon Dioxide-Nitrogen System, Brij Raj Misra

Masters Theses

"The purpose of this study was to provide compressibility factor data on the ethane - carbon dioxide - nitrogen system. Compressibility factors were experimentally determined for 5 mixtures at room temperature, 100ºF, 125ºF , 150ºF and pressures ranging between 1000 psig to 4000 psig. An attempt was also made to compare the experimental data with the compressibility factors obtained by the additive volume method. The deviation of the computed compressibility factor from the experimental data was found to be in accordance with the general view of previous workers. However, the deviation was found to be a maximum in the pressure …

Go to article

The Anodic Dissolution Of Tungsten, Ching-Lun Wu Jan 1970

The Anodic Dissolution Of Tungsten, Ching-Lun Wu

Masters Theses

"The anodic dissolution of tungsten was studied in H₂SO₄-K₂SO₄ solutions (pH= -2 to 2.5) andK₂SO₄-K₂CO₃-KOH solutions (pH = 11.5 to 14.5) at 25ºC. Faradaic efficiency studies in basic solutions showed that the metal was oxidized to the +6 state. In acid solutions, a thick protective film of yellow WO₃ was formed. Polarization measurements showed linear Tafel behavior (slope ~ 2.3RT/F) in the potential region slightly more positive than the rest potentials. An anodic dissolution mechanism is proposed which involves a surface film of W₂O₅ that is further oxidized to WO₃ and dissolves by hydrolyzation"--Abstract, page 1.

Go to article

Probe Detection Of Microwave Perturbation In A Magnetoplasma, Show-Ran Peter Wang Jan 1970

Probe Detection Of Microwave Perturbation In A Magnetoplasma, Show-Ran Peter Wang

Masters Theses

"When a microwave signal with a frequency near the electron upper hybrid resonance is applied to a magnetoplasma, it will excite the plasma. The perturbation of plasma can be detected by using Langmuir probes. The particular plasma used in this experiment is an argon discharge type and the density is relatively low (n~10⁸ cm⁻³). The electron temperature is about 7000º K. Because a magnetic field is applied to the plasma, it is necessary to use the probe theory in a magnetic field to calculate the electron number density from the electron temperature. In order to determine the electron upper hybrid …

Go to article

Surface Energy Determinations In Plexiglas, Li-King Chen Jan 1970

Surface Energy Determinations In Plexiglas, Li-King Chen

Masters Theses

"Under irreversible conditions an effective surface energy of plexiglas for notched bars deformed in three-point bending was measured. The various equations proposed for evaluating surface energy are described and values of surface energy obtained using these equations are reported for a variety of sample dimensions. A comparison has been made between the results obtained. The effect of different notch shapes, sharp V, square U and round, on calculated values and fracture characteristics are noted. The Griffith theory is shown to be valid for large crack dimensions"--Abstract, page ii.

Go to article

The Dinary Numerical System And Its Applications To Modern Parallel Processing Computers, Hai Chi Koo Jan 1970

The Dinary Numerical System And Its Applications To Modern Parallel Processing Computers, Hai Chi Koo

Masters Theses

"The Dinary Numerical System (DNS) is an extension of Binary Numerical System. By utilizing the newly developed Large-Scale-Integration technology, DNS can be implemented as a new concept of computer organization which has the merits of parallel processing. DNS consists of three field elements: they are -1, 0, and +1. Since DNS representation is not necessarily unique, new algorithms to generate the number of representations and all equivalent representations are presented in this paper. A Block-Oriented-Computer (BOC) is developed as an array of computing systems. For each of the systems, the arithmetic unit is essentially a modified Digital Differential Analyzer. The …

Go to article

First Prev Next Last