Engineering Commons^™

A Gamma-Level Portable Ring-Core Magnetometer, Stanley V. Marshall

Electrical and Computer Engineering Faculty Research & Creative Works

A four-transistor circuit is described for a battery-operated magnetometer that has 0.1 γ resolution using t-in diameter 4–79 or 6–81 Mo-Permalloy tape cores of 20–40 Mx capacity. The center-tapped drive winding also serves as the sense winding, simplifying the sensor assembly. Some signal-to-noise results are presented to illustrate the fairly wide difference that may exist between cores of the same cross section and to demonstrate the advantage of reducing core area. Copyright © 1971 by The Institute of Electrical and Electronics Engineers, Inc.

A Stable Explicit Method For Simultaneous Quasi‐Linear Differential Equations, Roy J. Brunson, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Effects Of Molecular Characteristics Of Polymers On Drag Reduction, Gin‐Chain ‐C Liaw, Jacques L. Zakin, Gary Kent Patterson

Chemical and Biochemical Engineering Faculty Research & Creative Works

Turbulent measurements in capillary tubes and in pipes were made on nonpolar solutions of seven polymer species, three at more than one molecular weight, over wide concentration ranges. A critical concentration, Cc, was taken as the minimum concentration for disappearance of the turbulence transition region. Above this concentration, friction factor‐generalized Reynolds number data show only a gradual deviation from extension of the laminar line. Cc increases with tube diameter and decreases with molecular weight. The critical dimensionless volume friction Cc [η] is less dependent on molecular weight. The levels of Cc [η] for different polymer species in a given tube …

The Anodic Dissolution Of Tungsten, James W. Johnson, Cheng-Hsiao Wu

Chemical and Biochemical Engineering Faculty Research & Creative Works

The anodic dissolution of tungsten was studied in H₂SO₄-K₂SO₄ solutions (pH = -2 to 2.5) and K₂SO₄-K₂CO₃-KOH solutions (pH = 11.5 to 14.5) at 25 C. Faradaic efficiency studies in basic solutions showed the metal to be oxidized to the +6 state. In acid solutions, a thick protective film of yellow WO₃ was formed. Polarization curves possessed linear Tafel regions (slope ~ 2.3 RT/F) at potentials slightly more positive than the rest potentials. An anodic dissolution mechanism is proposed which involves a surface film …

Mass Transfer Inside Liquid Droplets And Gas Bubbles Accompanied By A Second‐Order Chemical Reaction, R. J. Brunson, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Diffusion Coefficients Of Ethylene Glycol And Cyclohexanol In The Solvents Ethylene Glycol, Diethylene Glycol, And Propylene Glycol As A Function Of Temperature, Ronald D. Mitchell, James W. Moore, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Organic Desorption From Carbon-I. A Critical Look At Desorption Of Unknown Organic Materials From Carbon, S. C. Allen, R. H. Pahl, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Open-Channel Profiles By Newton's Iteration Technique, D. L. Fread, Terence E. Harbaugh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Computation of surface profiles for steady gradually varied flow can be accomplished by use of Newton's Iteration Technique. The magnitude of error is controlled and the profile depth can be conveniently calculated at selected distances upstream or downstream from a control point. A Fortran IV program is provided for utilizing the technique in a trapezoidal channel. © 1971.

Report On The School Of Mechanical Engineering National Technical Center Saigon, South Vietnam, Myrne R. Riley

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

"Training in the discipline of Mechanical Engineering is offered in South Vietnam by the School of Mechanical Engineering, one of four engineering schools and a Merchant Marine School composing the National Technical Center located presently in the Phu Tho region of Saigon, South Vietnam. The school was established in 1956 for the training of engineers, for mechanical and industrial activities. It became part of the National Technical Center, established by Decree No. 213-Gd by the President of the Republic of Vietnam on June 29, 1957 and graduated the first class of 20 in the summer of 1960. The KS Degree, …

Floating Bubble Configurations, Robert A. Medrow, B. T. Chao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The configurations of bubbles floating at a vapor-liquid interface are investigated both analytically and experimentally. The differential equations governing the shape of a single bubble at rest in a liquid of infinite extent are deduced under the assumption of zero dome thickness, uniform surface tension, and equal gas densities within the bubble and above the interface. These equations show that nondimensional bubble shapes depend upon the value of a single parameter. An analytical solution, valid for small bubbles, is developed and shown to be in good agreement with the general numerical solution. Good agreement with theory is demonstrated for floating …

Heat Transfer From An Oscillating Horizontal Wire, Bassem F. Armaly, D. H. Madsen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The effect of vibration on heat transfer by natural convection has been investigated experimentally using a thin wire, 0.010 in. in diameter, and air as a convection medium. Horizontal reciprocating motion of varying amplitudes, peak-to-peak values of 0-2.655 in., and frequencies, 0-20 cps, was applied to an electrically heated horizontal wire. The average wire velocity (frequency times total path length traveled per cycle by the wire) was used to correlate and predict the experimental results. © 1971 by ASME.

Density Distribution Measurements In Rarefied Gases Contained Between Parallel Plates At High Temperature Differences, Darryl J. Alofs, Richard C. Flagan, George S. Springer

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Density Distributions Were Experimentally Determined in Rarefied Gases at Rest Contained between Two Parallel Plates Maintained at Widely Different Temperatures. the Temperatures of the Hot and Cold Plates Were ∼79°K and ∼294°K, Respectively, Resulting in a Temperature Ratio of About 4:1. Both Helium and Nitrogen Were Used as Test Gases. Particular Attention Was Focused on Obtaining Data in the Temperature Jump and Transition Regimes. the Gas Densities Were Measured by Observing the Luminescence Produced by a High-Energy Electron Beam Traversed between the Plates. in Addition to the Density Measurements, Heat Transfer Measurements Were Also Made in Order to Estimate the …

The Axial Contact Of Finite Elastic Cylinders With Application To Thermal Contact Resistance, Ross Orlo Mcnary

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Predictions of the macroscopic thermal contact resistance have been severely restricted because the macroscopic contact area between finite members could not be determined. A new method of solution to this contact problem in elasticity is developed which is applicable to a wide variety of geometries and boundary conditions. A physical lumped-parameter model is employed from which the finite difference equations in terms of displacement are derived. Calculations using this method indicate that large errors in the prediction of the thermal contact resistance can result if solutions for bodies of infinite extent are employed for finite regions of interest. Especially large …

The Anodic Dissolution Reaction Of Insb: Etch Patterns, Electron Number, Anodic Disintegration, And Film Formation, Martin E. Straumanis, Lih Da Hu

Materials Science and Engineering Faculty Research & Creative Works

The etching behavior of the inverse {111} planes of undoped, semiconducting, n-type, InSb single crystals was explored. Depending upon the etchant, including anodic dissolution, various etch patterns were obtained on the inverse planes. In general, the etch pits on the In{111} plane were round, and the face was shiny, whereas the face of the inverse plane was dark and rough. The rates of dissolution in the electrolytes used were very low, especially in absence of oxidizers. The components dissolve as In3+ and Sb3 +. At current densities above 40 or 60 mA cm-2 (on Sb{111} or In{111}), growth of a …

A Magnetic Aftereffect In Dilute H.C.P. Co-C Alloys, J. R. Keiser, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

A magnetic Dis accommodation in dilute h.c.p. Co-C alloys has been observed around 90°C. The thermally activated process giving rise to the Dis accommodation is characterized by an activation energy of 26 kcal mole-1 and an attack frequency on the order of 10+13 sec-1. An application of the selection rules shows that the Dis accommodation cannot be caused by the redistribution of tetrahedral or octahedral interstitials or any nearest neighbor interstitial pairs as long as the defects interact linearly with the internal magnetic field. © 1971.

Charges On Jet Drops Produced By Bursting Bubbles, Robert A. Medrow, B. T. Chao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The sizes and charges of jet drops produced by bursting air bubbles are examined experimentally. The variation in charge for bubble lifetimes of up to 200 sec in NaCl and KCl solutions is reported. Jet drops refer to drops produced by a jet rising from a cavity left in a liquid surface by a bursting bubble; bubble lifetime is the interval during which a bubble is in motion between generation and rupture. With other variables held constant, drop charge shows a characteristic variation of a rise to a maximum followed by a decrease to an asymptotic value, as bubble lifetime …

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 …

A Laboratory Study Of The Transmission Of Signals Through Solid Material With Possible Application To Seismic Communication, Ronald Willis Carter

Masters Theses

"The problem of transmitting acoustic signals through solid material channels is investigated using piezoelectric transducers for generation and detection of the signals. Laboratory experiments are performed in which a solid material channel is modeled by a block of Berea sandstone. The magnitude of the frequency response for the sandstone and transducer combination is obtained over the frequency range of approximately 0 Hz to 500 kHz. Various electrical waveforms are utilized as driving sources for the transmitting transducer. It is found that the best received waveform is obtained when a gated sinewave whose frequency is approximately equal to the resonant frequency …

The Influence Of Member Length On Thermal Contact Resistance In A Vacuum Environment, Larry Martin Cooper

Masters Theses

"An investigation was conducted to determine the influence of member length on thermal contact resistance in a vacuum environment. A model was created which consisted of a center rod axially loaded between two other members. It was assumed that circular macroscopic constriction areas were formed at the contact interface when the rods were loaded. Macroscopic modeling of the contact surfaces makes the thermal contact analysis a function of the mechanical and thermal boundary conditions of the total body. The method of finite differences was employed to calculate the temperature distribution, heat flows, and thermal contact resistance of each member. Data …

Shear Properties Of An Organic Soil And The Same Soil With The Organic Matter Removed, David Eugene Daniels

Masters Theses

"The effect of strain rate on the shearing properties of an organic A̲ horizon Bryce clay and the same soil treated with hydrogen peroxide to remove the organic matter was studied. For both soils, the pore pressures were found to be independent of strain rate, and dependent only on the increment of strain during shear. The effect of the hydrogen peroxide treatment on the shear properties of an inorganic Bryce B̲ horizon clay was also studied. It was concluded that the hydrogen peroxide does not affect the mineral properties of the Bryce clay and serves only to selectively remove organic …

Phase Equilibrium And Thermodynamic Study Of The Iron-Copper-Carbon System, Krishna Parameswaran

Masters Theses

"Gas carburization experiments were conducted at 950ºC in order to study the phase relations and to determine the activity of carbon in the iron-rich corner of the iron-copper-carbon system. The solubility of graphite in equilibrium with iron-copper alloys was determined at 950º, 1000º, and 1050ºC. The results of gas carburization and graphite solubility experiments at 950ºC were used in constructing an isothermal section of the iron-rich end of the iron-copper-carbon phase diagram, on which are superimposed carbon isoactivity lines. Graphite solubility data at 1000º and 1050ºC were used to construct similar diagrams without the isoactivity lines. The effect of carbon …

A Hybrid Computer Solution Of The Swing Equation, Donald Wayne Shaw

Masters Theses

"Models for the governor and exciter control systems are presented and the development of a hybrid computing system including these models is described. A technique for including the governor and exciter effects into the solution of the power system swing equation is also discussed. A hybrid computing system consisting of an SCC 650 digital computer, hybrid interface, and an EAI-TR-48 analog computer is used to study five test cases. The test cases involve basically the same example system with different values for fault clearing times and machine inertias. The results of each test case are briefly discussed with relevance to …

The Concept And Design Of A Curvilinear Character Generator For Cathode Ray Tube Display Systems, Lawrence Edward Hanebrink Jr.

Masters Theses

"The character generator is the heart of any cathode ray tube display system. The types of generators in common use are the dot matrix generator, the raster scan generator, and the linear stroke generator. Each of these generators produces symbols whose legibility is somewhat compromised. A curvilinear generator is suggested which provides improved appearance and greater legibility. A prototype unit was constructed and the results are compared with the other generators. The curvilinear generator provides the best character resolution and readability of the generator types discussed"--Abstract, page ii.

Advanced Waste Treatment Of Industrial Waste Waters By Physicochemical Processes, Michael Gay Hardie

Masters Theses

"The primary objective of this investigation was to determine the general applicability of using physicochemical processes for treating different types of industrial wastes. Emphasis was placed on the evaluation of the treatment efficiency and the performance difficulties encountered in the treatment of each waste. Two types of waste were studied, one a high strength acidic industrial chemical waste and the other a petroleum refinery waste. The physicochemical system utilized included chemical coagulation and clarification plus activated carbon adsorption. Parallel operations of fixed-bed and expanded-bed carbon adsorbers were conducted. Treatment efficiencies were evaluated in terms of the removals of chemical oxygen …

The Skid Resistance Of Asphaltic Pavements Using Glass Aggregates, Michael Vaughn Korth

Masters Theses

"The disposal of the glass portion of solid waste is an ever-growing problem in the U.S. and recycling has been suggested as a possible solution. In order to find new uses for waste glass, investigations have been conducted to determine if the glass could be used as an aggregate in bituminous concrete mixtures. As part of the overall investigation, this study was concerned with investigating the skid resistance properties of the glass aggregate mixtures, called glasphalt. The objectives were to compare the skid resistance of various bituminous mixtures using aggregate combinations ranging from all glass to all conventional aggregate and …

An Investigation Of A Bistable Oscillator Used In A Phase Modulated Control Circuit, Yu-Fang Yen

Masters Theses

"A primary component in the investigation of phase modulated control systems is bistable oscillator which converts a constant oscillation signal to control the system. The oscillator is feedback type that utilizes a feedback capacitance and resistance in each feedback path to change its frequency. The theoretical behavior of bistable oscillator was investigated and the non-dimensional results were set for convenience in determining the oscillation period. The control circuit which based on the oscillator was also presented a form of suitable circuit for direct application to practical control problems"--Abstract, page ii.

High Temperature Compressive Creep In Mullite, Peter C. Smith

Masters Theses

"Compressive creep measurements were made on two groups of mullites at temperatures between 1455ºC and 1520ºC. The first group consisted of commercially manufactured mullites. The second group was made up of 7 different mullite compositions spanning the alumina-silica solid solution range from 3Al₂O₃ • 2SiO₂ to 2Al₂O₃ • SiO₂ . Thermal activation energies and stress exponents were calculated for the mullites in the second group. Steady state strain rates taken at 1460ºC under loads of 100 and 110 psi varied between 1.3x10⁻⁴ in/in/hr and 15.4x10⁻⁴ in/in/hr. Activation energies were between 109 Kcal/mole and 204 Kcal/mole. Stress exponents calculated from data …

A Software System For Interactive Man-Machine Design And Analysis Of Electronic Circuits, Leo William Midden

Masters Theses

"The development of an interactive computer-aided circuit analysis program is presented. A graphics terminal is used as an I/O device while an SCC 650 mini-computer is used as peripheral processor. The central processor is an IBM 360/50.

Formulation, capabilities and use of the system are discussed in detail. Close attention is given to user control, making the system both useful and versatile. Both hard and soft copies of all plots and tabular data are available. Provisions are made for error corrections and changes at each step of the input. Parameter values can be altered before and after each analysis.

Additionally, …

Mechanical Properties Of Low Carbon Martensite, Allen L. Affolter

Masters Theses

"Steels of three different compositions were heat treated and tensile tested in order to determine their mechanical properties after heat treatment. All samples had near 0.20 per cent carbon and two manganese levels 0.90 per cent and 1.35 per cent. One group containing the higher manganese level also had small additions of columbium and vanadium. The specimens were too brittle in the as-quenched condition to be loaded to full strength. Maximum strength and ductility were found after short time tempering at low tempering temperatures -- 2 to 15 minutes at 200º to 300ºF. Higher strengths were found at the low …

Practical Application Of Digital Computer To Distribution Systems, Juan Vincente Saavedra

Masters Theses

"Given a three phase ac power distribution system, a digital computer program is presented which determines a complete steady state solution for a given condition. The network data is processed by the computer into an admittance matrix, and these parameters are stored in a manner that enables the computer program to operate upon them as the coefficient of a simultaneous set of nonlinear equations. This set of equations are solved by the Gauss-Seidel Iterative Process improved by a modification of the relaxation method. Practical experience with the distribution system of the Davenport, Iowa, plant of the Aluminum Company of America …