Engineering Commons^™

The Anodic Dissolution Of Cadmium In Aqueous Solutions, San-Cheng Lai

Doctoral Dissertations

"The purpose of this investigation was to study the effect of cadmium ions on the anodic dissolution of cadmium in salt solutions of ·constant ionic strength. The concentration of the cadmium ions was varied from 0.001 to 1 N and the current density ranged from 0.001 to 0.1 amp•cm^-2. The temperature was controlled at 25°C.

....A mathematical model was postulated expressing the anodic dissolution rate as the sum of electrochemical, local corrosion, and disintegration rates."--Abstract, page iii.

An Investigation Of The Induction Heating Characteristics Of Powdered Susceptors Dispersed In A Non-Conducting Medium, Robert Leon Wright

Doctoral Dissertations

"This investigation determined some of the induction heating characteristics of powdered magnetite, iron and ferrosilicon susceptor dispersed in silica sand which had been coated with thermosetting resin. The powdered susceptor particles in the mixture were heated by the field of an induction coil, consequently heating the resin coated sand and bonding the sand grains together.

It was found that the type, relative amount,and particle size of the susceptor were important variables to be considered in the induction heating characteristics. Hysteresis losses in the susceptor particles, which are a function of the coil current, frequency, and permeability, appear to be the …

Hydrogen Absorption And Corrosion Studies Of Zone-Refined Iron, Chang Don Kim

Doctoral Dissertations

"The lattice constants of zone-refined iron filings and iron whiskers are 2.86623 and 2.86626 Å at 25°C respectively. Their thermal expansion coefficients are both the same, 12.1 x 10⁻⁶ /°C at temperatures 10 - 65°C.

The influence of hydrogen on the lattice constant of iron was investigated and it was found that hydrogen has no effect (within the limits of errors) on the lattice constant of iron at room temperature regardless of the charging methods. However, at elevated temperatures hydrogen expands the iron lattice due to increased solubility of the gas. The lattice constant of iron in vacuum and in …

A Study Of The Anodic Oxidation Of Acetylene On Gold Electrodes, Jo Lisle Reed

Doctoral Dissertations

"The object of this investigation was to establish a mechanism for the anodic oxidation of acetylene on gold electrodes in aqueous solutions. It is known that anodic oxidation of organic compounds on gold electrodes produces a large number of organic intermediates and end products. Therefore, it appeared worthwhile to establish a mechanism that could provide a better understanding of the fuel cell electrode kinetics and possibly lead to new methods of organic syntheses"--Introduction, page 2.

Turbulence Measurements In Polymer Solutions Using Hot-Film Anemometry, Gary Kent Patterson

Doctoral Dissertations

"Hot-film anemometry was used to study the detailed structure of turbulence (intensities, energy spectra, and auto-correlations) in Newtonian solvents, non-drag reducing polymer solutions, and drag reducing polymer solutions. This was done in two smooth wall tubes with diameters of 1.0 inch and 2.0 inches. A probe traversing mechanism was used for measurements at radial positions from the center to as near the wall as possible for both the film probes (r/a=0.85 in the 2-inch tube) and the impact tubes (r/ a=0.98). The impact tubes were used to measure velocities for film probe calibration.

The solvents used in this investigation were …

The Statistical Mechanics Of Kink Interactions, Michael Brewer Mcneil

Doctoral Dissertations

"Using a potential derived from continuum elasticity, the interactions between kinks on a dislocation line are studied as special cases of the problem of a one-dimensional system of interacting particles. By the use of constant pressure ensembles, the principal kink-interaction problems of physical interest are solved. The application of these solutions to the theoretical analyses of work hardening and internal friction is explored and comparisons made to previous work in which kink interactions were neglected; it is found that, as would be expected, variations of equilibrium kink populations with external stress cannot account for the Bordoni peak, which must therefore …

Temperature And Stress Distributions Produced In Long Circular Cylinders Cooled By Emission Of Thermal Radiation, Robert S. Pritchard

Mechanical Engineering ETDs

This study involves the determination of the temperature and stress distributions produced in long circumferentially symmetric circular cylinders cooled by emission of thermal radiation from the lateral surface. Temperature and strain responses obtained from an experimental model are presented for a set of parameters which correspond to the highest strain level which could be accurately determined with the strain gages. These responses are in good agreement with the results obtained by solution of an appropriate mathematical model. Temperature responses obtained from the same model, but having a higher initial temperature, are also presented and compared with analytical results. Reasonably good …

Galvanomagnetic Effects And Related Phenonmenon In Semiconductors And Dielectrics In A Radiation Environment, Leroy C. Meyer

Electrical and Computer Engineering ETDs

From Introduction:

In 1878, Hall found that the stream lines of an electric current in a metallic conductor were distorted when the conductor was placed in an external magnetic field. This distortion arises from an electric field set up at right angles to the current and to the magnetic field. The effect is well known in conductors and semiconductors, for both steady state and low frequencies Figure 1-1 illustrates the polarities of the Hall voltage for Ix in the direction of conventional current flow.

Drag Forces On Magnetically Accelerated Particles, Darrell Winterton Walker

Theses and Dissertations

The object of this investigation was to determine the effect of acceleration on the drag of spheres as it differs from the steady state case. Steady state drag applies to the force acting on a single sphere moving at constant velocity through an infinite, continuous, incompressible, turbulence free fluid. Extensive experimentation has quite thoroughly documented the steady state drag characteristics of spheres. A dimensionless parameter associated with the drag force is sometimes used to correlate drag characteristics.

Heat Transfer In Shock Boundary Layer Interaction Regions, Rex W. Shumway

Theses and Dissertations

The interest in aerodynamic heating problems has been increasing rapidly in the last decade. This interest is no longer concentrated on the heating of simple shapes for which adequate heat transfer theory has been developed« Because of the increasing Mach number ranges of aircraft, the need for information on the aerodynamic heating of various components has become imperative. Only when the magnitude of the problem has been exposed can the design for reducing the severity of local heating be optimized. Definition of these problems is of interest, not only because of the flow phenomena, but because of possible design limitations …

The Investigation And Design Of A Powered, Single-Man Parawing Aircraft, Calvin J. Merrell

Theses and Dissertations

During the last few years there has been an increasing interest in a high-lift wing configuration known as the flex-wing, or parawing. The parawing consists basically of a flexible membrane such as cloth, attached to two leading edges (or booms) and a keel as shown in Figure 1. At angles of attack (��) greater than the billowing angle (��). the air impinges on the under side of the membrane and forces it into a double-arch shape at each cross-section. When straight leading edges are used, each arch approximates the shape of a conical section. A cylindrical section is obtained by …

Turbulent Flow In The Entry Region, Chin-Hsiu Li

Theses and Dissertations

When entering into the subject of turbulent flow, it is essential to understand that the kind of flow with which we deal belongs to a particular class known as shear flow. These types of flow comprise flow fields in which relative velocities have been induced by shear stresses rather than by the action of pressure forces. In pipe flow, when the fluid enters through the well-rounded bell from a reservoir or from the calm open air, a uniform velocity distribution occurs at the pipe entrance. Immediately down stream from the entrance of the pipe, the flow is structured with a …

The Vibration Response Of Laminated Orthotropic Plates, Max E. Waddoups Jr.

Theses and Dissertations

The behavior of anisotropic materials has been the object of much recent research® The high strength to weight ratio needed by aerospace structures has necessitated the use of exotic, composite materials which generally exhibit anisotropic behavior® These materials cannot be fully utilized unless analytical techniques are used which take maximum advantage of their anisotropic behavior.

Liquid Particle Interaction With A Normal Shock Wave, Victor George Forsnes

Theses and Dissertations

The atomization of a liquid by an air stream has been an item of much concern in the past, and there have been numerous experimental studies of the process made in an effort to correlate liquid and air- stream physical properties into a general model which will predict the degree of and the time required for atomization for a given physical situation. The breakup of liquid drops, a major portion of the atomization process, finds application in the field of meteorology, where the formation, breakup, and shape of raindrops is an item of much concern; in the field of internal …

Prediction Of Batch Heat Transfer Coefficients For Pseudoplastic Fluids In Agitated Vessels, Donald William Hagedorn

Dissertations

Experimental batch heat-transfer data were obtained for both Newtonian and pseudoplastic liquids in a baffled agitated vessel. The fluids tested had flow behavior in-dexes between 0.36 and 1.0; and the apparent viscosity ranged from 1 to 1200 centipoise. Four types of impellers (anchor, paddle, propeller, and disk and vane turbine) were studied using eleven separate impellers. The probable error in the measured heat transfer coefficient was ± 20 percent.

The effects of the generalized Reynolds number, generalized Prandtl number, and viscosity ratio were studied. In addition the effect of impeller diameter was studied for paddles, propellers, and turbines; and the …

Optimum Linear And Adaptive Polynomial Smoothers, Stanley Bruce Alterman

Dissertations

The design of optimum polynomial digital data smoothers (filters) is considered for linear and adaptive processing systems. It is shown that a significant improvement in performance can be obtained by using linear smoothers that take into account known a priori constraints or distributions of the input signal. The procedure for designing optimum (minimum mean square error) adaptive polynomial data smoothers is then discussed and analyzed. The optimum smoother makes use of a priori signal statistics combined with an adaptive Bayesian weighting of a bank of conditionally optimum smoothers. Use of this technique permits large improvements in performance with a minimum …

The Electrochemical Oxidation Of Cholesteryl Acetate Dibromide, Abraham Cooper

Dissertations

Cholesteryl Acetate Dibromide was dissolved in carbon tetrachloride, suspended with mixing in 4.5 molar solution of sulfuric acid and electrolyzed at a lead dioxide anode. The anodically prepared film of lead dioxide, when maintained at potentials (relative to a calomel electrode) above 1.5 volts, was a catalyst for the oxidation. A new and mild oxidation took place at the catalytic electrode surface that resulted in attack on the tertiary hydrogen atom at the 25 carbon. The mildness of the oxidation prevented the decomposition of the unconverted raw material and permitted the recovery of up to 96% of the cholesteryl acetate …

Current-Potential Effects Of Trace Impurities In Manganese Electrowinning, George Robert Ferment

Dissertations

The purpose of this investigation was to study the effects of trace metallic impurities, found in manganese electro-winning solutions, on cathode current-potential curves.

This investigation led to the development of a novel analytical tool, emphasizing polarization curves as a means of detecting trace metallic impurities in manganese sulfate electrolytes. The method possesses two distinguishing features: (a) it uses the competing hydrogen evolution reaction as a means of detecting metallic impurities, and (b) it enables one to establish if the electrolyte is sufficiently pure for efficient electrolysis.

Nine metallic impurities were studied, consisting of: nickel, cobalt, silver, copper, zinc, molybdenum, cadmium, …

Effect Of Particle Size And Particle Size Distribution On The Burning Rate Of Barium Chromate-Boron Pyrotechnic Delay Compositions, Donald J. Freeman

Theses

The burning rate of barium chromate-boron delay compositions is shown to be related to the 10 percent particle size point on the particle size distribution curve (particle size vs. percent greater than size) for either of the components. The burning rate is also shown to be inversely proportional to the 10 percent point of the barium chromate; and to follow a hyperbolic type relationship with the 10 percent of the boron, decreasing asymptotically as the 10 percent point increases. No correlations were found between the burning rate of the compositions and the average particle diameter, the mean particle diameter, or …

Cation Exchange Between Solutions Of Ferric Nitrate And Dowex 50x-8 Resin, Michael H. Mansky

Theses

The rate of exchange of ferric ions from solutions of ferric nitrate and hydrogen ions from Dowex 50X-8 has been studied in an agitated bed ion exchange column over a range of bed loading conditions. Agitation has been maintained in a regime known to indicate film diffusion control of rate in small scale batch reactors.

Calculated diffusion coefficients for the column are slightly higher than those determined in the batch reactor because of greater turbulence of agitation in the column.

The assumption of previous investigators concerning linearity of equilibrium data has been found to be invalid for the system studied. …

Factors Affecting The Biodegradation Of Linear Alkylbenzene Sulfonates In River Die-Away Studies, Neil M. Mchugh

Theses

The determining factors in the biodegradation of linear alkylbenzene sulfonates have been investigated using the river die-away technique. Emphasis was placed on finding the correlation between biodegradability and each of the following: surfactant structure, inoculation of basic water medium with activated sludge, and acclimation of bacteria to a given surfactant. It has been shown that the lower the molecular weight of linear alkylate, down to C8, the faster the rate of biodegradation. It was further shown that there is no direct relationship between phenyl position distribution and biodegradability, nor is there any direct correlation between the amount of surfactant remaining …

Use Of Gas Chromatography To Determine The Mutual Solubility Of Water And Toluene, John Orshich

Theses

The possibility of determining the water traces in water saturated toluene as well as the traces of toluene in toluene saturated water by means of gas chromatography was investigated.

A 15 feet long, 1/4 inch copper column, attached to F & M Chromatograph 500, was used; the column was packed with 5 Armeen SB on Haloport F (Teflon).

The determination of toluene in toluene saturated water did not appear to be feasible, since the retention time for toluene with the used column was too short to allow the base line of the recorder to become steady at the attenuation value …

A Study Of Emulsion Viscosities, Frederick R. Cummings

Theses

The apparent viscosity of stable emulsions has been measured and evaluated. The systems studied consisted of various oil in water emulsions, utilizing a series of six n-paraffins from heptane to octadecane. The system was stabilized with a conventional emulsifying agent. The apparent viscosity of these emulsions was studied in relation to (a) the concentration of the disperse phase and, (b) the viscosity of the hydrocarbon used as the continuous phase.

It was established that the volume concentration of the disperse phase had considerable effect on the apparent viscosity of the emulsion. An increase in the concentration of the disperse phase …

The Effect Of Column Diameter On The Efficiency Of Packed Fractioning Towers, William Lintner

Theses

The object of this work was to study the effect of packed column diameter on the fractionation efficiency so that a more reliable engineering approach could be employed in the scaling up of fractionating columns.

The height equivalent to a theoretical plate (HETP) was employed to compare column efficiencies in this study. The HETP was calculated for several gas mass velocities through columns of one-inch, two-inch and three-inch diameter, packed with one-quarter inch Berl saddles. All data were collected at total reflux conditions employing the standard n-heptane-methylcyclohexane binary.

The results indicated that the efficiencies of the one-inch and two-inch diameter …

Heat Transfer To Non-Newtonian Fluids In Turbulent Flow, Donald S. Smalley, George Vassil

Theses

An investigation of the heat transfer characteristics of non-Newtonian solutions in turbulent flow is presented. The range of flow behavior indices (n) was examined from 0.69 to 0.88. The consistency index (K) was investigated over the range of 0.00008 to 0.002 lbsf x sec^n'/ft². The Reynolds number varied between 2200 to 25,000.

Two methods of correlating film coefficients which have been previously developed were examined. Improvement in the reliability of correlation is demonstrated by modifications proposed in this work.

Brittle Fracture Of Carbon Steel, Ronald Robert Stang

Theses

This thesis is a report on the research and engineering efforts made, since 1957, to further define the causes and means for the prevention of catastrophic brittle fracture of carbon steels at ambient temperatures. All of the data based on the literature published from 1958 to 1965 has been critically examined and correlated.

Included are discussions of the factors affecting brittle fracture and the tests used to predict resistance Of steels to brittle fracture. Correlations of tests with actual service performance and relationships between tests are discussed. A review and critical evaluation of present day steel specifications as they affect …

The Thermal Conductivity With Vapor Pressure For N-Paraffin Hydrocarbons, Jacob Tolsma

Theses

A literature search of the thermal conductivity of pure liquids has been made and experimental values have been compiled. Study of the theory of the thermal conductivity of liquids indicated that a relationship exists between thermal conductivity and viscosity. Previous investigations have found an almost linear relationship between the logarithms of viscosity and vapor pressure for n-paraffin hydrocarbons. In this investigation the logarithm of thermal conductivity plotted versus the logarithm of vapor pressure for the same series was also found to be almost linear. The equation of the line when combined with a linearized Antoine equation in terms of the …

Investigation Of The Octene-Decane-Urea Adduct Equilibrium System, Frederick Charles Guest

Theses

Concentrations of equilibrium mixtures formed by adding increments of octene to a solution of urea in methanol to form adduct are reported.

Calorimetric studies indicate that the addition of octene to a urea-methanol solution shows an endothermic heat effect prior to the formation of solid adduct. The heat effect becomes exothermic as solid adduct is formed.

Addition of decane to an equilibrium octene-urea adduct system increased octene concentration in the supernatent liquid, indicating an octene release from the original adduct as decane adduct was formed.

The order in which decane and octene were added to form the decane-octene-urea adduct system …

Activity Coefficient For Infinite Dilute Solution By Gas-Liquid Chromotography, Suresh Jivabhai Patel

Theses

Gas-liquid partition chromatography has been used to determine the activity coefficient for very dilute solutions of solute in non-volatile solvents.

Other, more classical methods of determining the activity coefficient are laborious and are neither as accurtate nor as precise as desired.

The systems studied were:

(1) Benzene-Dinonyl Phthalate

(2) Cyclohexane-Dinonyl Phthalate

(3) Benzene-Squalane

(4) Cyclohexane-Squalane

All systems were studied over the column temperature range of 50° to 110°C with constant pressure and sample size. A study was also made on the effect of column pressure at constant temperature and sample size. One system was studied with variable sample size but …

Residual Stresses And The Bauschinger Effect, Raymond M. Huebner

Theses and Dissertations

Within the last ten years there has been much interest in the field of elasto-plastic behavior of engineering materials. Hie recent popularity of the low-cost light-weight plastically designed structures has added a great deal of impetus to this interest. This thesis deals with one of the aspects of elasto-plastic behavior, namely, the distribution of the residual stresses in a simple member which has been plastically deformed in tension and/or compression,. In particular, an attempt has been made to relate these residual stresses to the well-known but little understood Bauschinger effect.