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Subcritical Flow Over Various Weir Shapes, M. Leon Hyatt, Gaylord V. Skogerboe, Lloyd H. Austin

Reports

Submerged flow exists for any given structure when a change in flow depth downstream from the structure causes a change in flow depth upstream from the structure for any given constant value of discharge. The two flow depths, normally measured when submerged flow exists, consist of a depth upstream from the structure, which is used also for free flow conditions, and a depth of flow located any place downstream from the structure. The initial studies in which the submerged flow analysis was developed were made on flat-bottomed flumes (Hyatt, 1965; and Skogerboe, Walker, and Robinson, 1965). Later studies verified the …

Anodic Dissolution Of Lead In Aqueous Solutions, Christopher Kuo-Chieh Wu

Masters Theses

"The apparent valence of lead was determined in one normal solutions of potassium nitrate, ammonium acetate, lead nitrate, and lead acetate at temperatures of 25 and 50°C. The current density was varied from 0.001 to 1.00 amp•cm ^-2. The apparent valence of lead ranged between 1.90 and 2.00 in all solutions. The lower valences were reached at higher current densities. The amount of disintegration was very small, and was dependent upon film formation on the surface of the anode.

Potential-current density relationships for the anodic dissolution of lead were obtained in the electrolytes mentioned above. In potassium nitrate and …

Measurement Of The Velocity And Temperature Profiles Of Air Swirling Through A Conical Shaped Nozzle, Stephen Abner Thompson

Masters Theses

"A study was conducted to determine the velocity and temperature distributions in swirling flow of air through a converging nozzle. Radial traverses were taken at three axial positions with a specially designed pitot tube constructed of hypodermic needles. The most significant finding was the large magnitude of the radial velocity component. A combination of reversed axial flow along the nozzle axis, and an outward flow near the nozzle surface was also experienced. An increase of temperature with increasing radial position may be attributed to the Ranque-Hilsch effect"--Abstract, page ii.

The Kinetics Of The Reaction Of M-Nitrobenzyl Bromide With Hydroxide Ion In Aqueous-Aprotic Solvent Mixtures, Ramesh Nagindas Sheth

Masters Theses

"The reaction between m-nitrobenzyl bromide and sodium hydroxide in homogeneous aqueous dioxane and aqueous tetrahydrofuran media was studied.

The product of the reaction was identified by infrared, gas chromatography and chemical tests as m-nitrobenzyl alcohol.
The kinetics of the reaction are second order with practically no variation in the rate constants as the % of the organic solvent was changed in the medium. This seems to imply hydrolysis of the organic halide by a process involving both bond-breaking and bond-formation in the transition state.
The activation energy, measured in 50% aqueous dioxane, between 20⁰ and 69.5⁰C at 5 different temperatures, …

Checking Rigid-Framed Structures By Extended Moment-Area Equations, Lucky Li-Chi Chow

Masters Theses

"Using the known moments obtained from the moment distribution solution, the extended moment-area equations are used to check whether or not delta x, delta y, delta theta are truly zero, or are any other quantity they are supposed to be. In order to get a reasonably correct answer, a solution must meet both the elastic checks and the static checks for their equilibrium and compatibility functions. Using the extended moment-area equations, the magnitudes of the slopes and deflections at all of the joints in framed structures can be found easily"--Abstract, page ii.

A Photoelastic Study Of The Stresses In A Deep Beam Using Partial Mirrors For Isochromatic Fringe Sharpening And Fringe Multiplication, Edward M. Raney

Masters Theses

"This paper is a photoelastic investigation of the stresses in a deep beam using partial mirrors to obtain isocromatic fringe sharpening and fringe multiplication. This method may be of particular value in photoelastic work for obtaining full field fringe multiplication and fringe sharpening for models which exhibit low fringe orders.

The photoelastic model used in this investigation is a deep beam with a length to depth ratio of one. A uniform load is applied over the center one-half of the beam. The beam is supported by two uniform loads distributed over a length of one-quarter the span.

A first approximation …

Modal Characteristics Of A Vibrating Truss, Edd Leighman Ghent Jr.

Masters Theses

"In this thesis, a complete technique is presented for the vibration analysis of any planar structure which can be classified in the broad category of trusses or frames. Although a theoretical backdrop is included for the' sake of completeness, the intent is to provide a technique that is readily adapted to computer usage and can be handled with a minimum of confusion or misunderstanding.

The problem is solved by the use of a displacement technique wherein the inertia and stiffness properties of a structure are calculated by superimposing the contributions of each component of the structure. The calculation of these …

The Plastic Behavior Of Reinforced Concrete Beams With Varying Percentages Of Reinforcing Steel Symmetrically Placed, J. Leroy Hulsey

Masters Theses

"The purpose of this study is to determine the limitations of the plastic behavior of reinforced concrete beams with varying percentages of high strength steel (ASTM-A-432) cutoff in the compression region d distance beyond the point of inflection. Comparison was made with the derived equations.

Steel was placed symmetrically in order to obtain like action at critical sections. The members tested were of a propped beam nature having a total clear span of 5'6" with a 6" overhang on one end and 1'6" overhang on the other. Concentrated loads were applied so as to obtain midspan loading and fixed end …

The Anodic Dissolution Of Magnesium In Aqueous Solutions, Chen-I Lu

Masters Theses

"The anodic dissolution of magnesium was studied in MgCl₂-KC1 and MgBr₂-KBr mixtures at 25, 40, and 55 °C. The parameters of the study were current density, concentration of magnesium ion, and temperature. The concentration of magnesium ions was varied from 0.001 to 1 N holding the ionic strength constant at 1.5. The weight loss of magnesium from the electrode during electrolysis was determined by weighing the electrode both before and after electrolysis. The current was measured with a sensitive milliammeter. The range of the current densities was varied from 0.001 to 0.1 amps·cm^-2. The …

Slope Stability Analysis Of A Fissured Glacial Clay, Byron G. Walker

Masters Theses

"A slope in an over-consolidated, fissured clay was analyzed by the Swedish Method of Slices.

Values of cohesion (c) and angles of friction (Ø) were determined by three different types of direct shear tests (undrained, drained and residual).

Factors of safety (functions of c and Ø) indicated that the direct shear test parameter gave a factor of safety approximately four times that represented by failure conditions in the field. Drained tests gave a factor of safety nearly 2.3 times the value represented by field conditions. The conclusion is made that these two tests are of limited value for slope stability …

Continuously Tapered Dielectric Matching Transitions For Waveguides, William E. Hord

Doctoral Dissertations

"Dielectric matching transitions at microwave frequencies are used for matching air filled waveguides into dielectric filled waveguides for maser work or into dielectric rod antennas. Also dielectric loading has been shown to improve the performance of the ferrite isolators.

The dielectric matching transitions that have been analyzed in the literature are of the stepped type. The continuously tapered dielectric matching transitions investigated in this dissertation provide increased bandwidth with very little increase of physical complexity.

The dissertation provides an analytical method for analysis and design for the continuously tapered dielectric matching transition. First-order and second-order approximate solutions for both symmetrical …

Nonparametric Detection Of Signals Causing Arbitrary Changes In The Accompanying Noise Backgrounds, John Joseph Komo

Doctoral Dissertations

"The detection of signals in the presence of noise is an important problem in the field of communications. The detection problem is concerned with the design of systems which determine only the presence or absence of a signal which occurs with background noise. An example of considerable importance, which is encountered quite frequently in practice, is the radar detection problem. In the radar problem it is desired to determine the presence of a target by detecting the presence of a radar return signal in noise. Another example is the seismic exploration problem which utilizes the detection of reflected signals from …

The Anodic Behavior Of Zinc In Aqueous Salt Solutions, Yun-Chung Sun

Doctoral Dissertations

"The increasing demand for protective metals as coatings and non-corrosive alloys has caused extensive research on the fundamental behavior of metals in corrosive media. The problem of controlling the destructive process of metallic corrosion still exists and becomes urgent in this space age. The desirablity of metals such as beryllium, magnesium, and zinc in air frame and space structural units, because of their high strength to weight ratio, has been responsible for the considerable progress in their technology in recent years.

The basic mechanism of the anodic dissolution of metals such as zinc, cadmium, and magnesium in salt solution is …

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 …

A Numerical Method For The Solution Of Cylindrical Shell Structures, Chen-Jow Hsiao

Masters Theses

"Many studies and analyses of shell structures to date have been either so complex and laborious as to preclude their application in practical design problems or so approximate, because of basic assumptions, as to limit their scope of application. Hence, a method of shell analysis which is convenient to use, reasonable in its results and general in its application is really needed. It is the purpose of this study to supply such a method of analysis.

In this investigation it is proposed to replace the shell structure which has an infinite number of degrees of indeterminancy with an analogous framework …

Numerical Solution Of Water Hammer Analysis Including Friction Losses, Lih Hsun Weng

Masters Theses

"The water hammer phenomena is a very important problem in pipe lines and gate operations. There are many analytical solutions tor water hammer problems including friction losses, but most of them use a linear approximation tor the friction effect that is different from the actual situation. Also the existing methods for solving water hammer problems involve difficult mathematical operations that are impractical and inaccurate.

In order to find a more rapid method for solving water hammer problems including friction losses and to obtain closer agreement with the actual condition, the problem is solved here using the basic partial differential equations …

An Investigation Of Failure Patterns Of Layered Specimens Loaded In Uniaxial Compression, Narendra Y. B. Choudary

Masters Theses

"Uniaxial compressive strength for two and three-layered specimens was obtained with different thicknesses of layers and also for different length to diameter ratios. The fracture and failure pattern was studied. Shear and extension fractures were observed in the layers. Geometry and end conditions of the specimen had a great influence in the failure and fracture pattern.

The uniaxial compressive strength of a layered specimen was found to be lower than the weighted average strength and either low or high when compared to the arithmetic average strength, depending on the ratio of the heights of the layers. The compressive strength of …

The Constant Impedance Tapered Lossless Transmission Line, Yu Kuo Chen

Masters Theses

"Considerable work has been done on the theory and development of the distributed RC network which is a special case of the general distributed network type of transmission line.

Sir William Thompson analyzed telegraph cables, assuming the RC line as a model. Oliver Heaviside made numerous contributions to transmission line theory. The solution of a two-wire transmission line with constant parameters R and C is obtainable by direct solution of the telegraphist's equations which are developed from the equivalent circuit of an incremental length of the network. The sinusoidal steady-state solutions of certain tapered RC lines have been exhibited. The …

Study Of Mass Transfer Through Porous, Water-Repellent Membranes, Virendra V. Tanna

Masters Theses

"A new method of desalination using a porous, water-repellent membrane was studied. The membrane utilized surface forces to support a vapor phase in its pores which separated the salt water from fresh water. The method used a vapor pressure difference across the membrane as the driving force for mass transfer of water from the salt water phase to the fresh water. This vapor pressure difference was obtained by maintaining a temperature difference between the two liquid phases.

The experimental data and results indicated the feasibility of vaporization through porous, water-repellent membranes. The flux of water through a membrane made of …

Empirical Evaluation Of The Eccentric Orifice In Small Diameter Pipes, Gary A. Hinz

Masters Theses

"This investigation has taken different orifice sizes (0.3005", 0.4000", 0.5045", 0.6015") and tested their flow characteristics when used in a 1" diameter pipe. Each orifice was initially placed in a fully eccentric position, that is the circumference of the orifice was placed tangent to the inside circumference of the pipe. Data was taken with the orifice eccentric to concentric in increments of 0.050".

Plots of flow coefficient versus Reynold's number were made for each position of the four orifices tested.

Empirical equations were developed for determining the flow coefficient of the various orifice sizes placed in any eccentric position.

It …

Effect Of Artificial Roughness On Convection, Lee W. Burford

Masters Theses

"Considerable work has been done in recent years, and is still being done, to find ways of increasing the heat transfer rate in fluid heat exchangers. One particular type of potential heat exchanger that has been studied analytically, as well as experimentally, is the use of artificially roughened tubing.

The test sections used in this experiment consisted of four aluminum pipes, three of which have been artificially roughened internally by machining ninety- degree V-shape grooves along the axis of the pipes. The grooves were 30/1000, 60/1000, and 90/1000 inches in depth. The remaining pipe was a smooth test section with …

Comparison Of Plastic Stress-Strain Material Properties As Determined From Conventional Experiments, Wen Mo Chen

Masters Theses

"In problems of engineering design, it is usually assumed that the stress-strain diagrams of a given material, as obtained from different loading conditions, are the same. In fact, by using the classical theory of plasticity, it can be shown that, with an appropriate selection of stress and strain related parameters, the diagrams should coincide.

Three different materials - magnesium, aluminum and steel, have been tested under tension, compression, torsion and bending loads. Stress-strain diagrams were constructed from these observations. This thesis presents an analysis of the relative agreement between the theoretical and experimental results of these materials"--Abstract, page i.

Catalytic Effects On Radiation-Induced Polymerization Of Methyl Methacryalate, David E. Bartine

Masters Theses

"A study has been made of the effect of Kaolin clay particle size and acidity on the degree of radiation-induced polymerization of methyl methacrylate. The results indicate that the degree of polymerization varies with the clay particle size, and that the amount of polymer produced is influenced by the pH of the clay"--Abstract, page ii.

The Performance Of A Countercurrent Extraction Column With Vibrated Packing, Mehmet Uran ÖZsoy

Masters Theses

"The performance of a continuous countercurrent extraction column with a packing -- that could be vibrated vertically at various amplitudes and frequencies by a variable speed motor -- was investigated under both non-flooding and flooding conditions using the high interfacial tension benzene-acetic acid-water ternary system. In all the experimental runs, which were sequenced randomly with a full-factorial experiment design, mass transfer of the solute (acetic acid) from the aqueous to the organic phase was studied. Column performance was evaluated in terms of the height of an overall transfer unit, HTU, based on the benzene phase. The variables studied were: amplitude …

A Study Of The Effect Of Magnetite Additions To Shell Molds On The Surface Quality Of Low Carbon Steel Castings, Robert C. Tooke

Masters Theses

"Shell molds containing additions of ten to fifty percent magnetite, Fe₃O₄, of various particle sizes were cured by induction heating. For comparison, regular shell molds were made using silica and zircon sand. Low carbon steel was cast into all of the molds.

Castings produced from the regular shell molds exhibited poor surfaces due to mold expansion. Magnetite additions eliminated the expansion defects from the casting surfaces.

Excellent surfaces were obtained on the low carbon steel castings with proper selection of the magnetite particle size and the percent of magnetite added. Improper combinations of size and amount …

Two-Dimensional Seismic Model Studies, Joong Hee Chun

Masters Theses

"The purpose of this research was to design and construct apparatus suitable for two-dimensional seismic model studies.

A new technique for two-dimensional seismic model testing was devised which allows wide application of the equipment. This enabled the author to place the source and receiver in any desired position on the model, thereby permitting the recording of seismic events as function of distance and depth at any position

Two simple geometric models were tested to demonstrate the experimental range of the apparatus designed. The recorded data were compared with theoretical predictions and were found to be in good agreement"--Abstract, page ii.

Nucleate-Boiling Heat Transfer To Water At Atmospheric Pressure, H. D. Chevali

Masters Theses

"The purpose of this investigation was to study the hysteresis effect, the effect of micro-roughness and orientation of the heat-transfer surface, and the effect of infra-red-radiation-treated heat-transfer surfaces on the nucleate-boiling curve.

It has been observed that there exists no hysteresis effect for water boiling from a cylindrical copper surface in the nucleate-boiling region over the range studied. The nucleate-boiling curve has been found to be independent of micro-roughness and orientation of the heat-transfer surface. There was no detectable change in the nucleate-boiling characteristics of the heat-transfer surface when the surface was treated with infra-red radiation"--Abstract, page ii.

Correlation Of Drag Reducing Data In Dilute Polymer Solutions, Jorge Mario Rodriguez

Masters Theses

"The purpose of this investigation was to obtain a correlation for drag reducing solutions in circular tubes under turbulent conditions. Data were taken for three polymer-solvent systems: polymethyl methacrylate V-100 (M_v ~ 110,000) in toluene, polyisobutylene L-200 (M_v ~ 4,700,000) in toluene, and polyisobutylene L-200 in cyclohexane. The data from the two polyisobutylene systems, together with other data on polymethyl methacrylate G (M_v ~ 1,500,000) in toluene and polyisobutylene L-80 (M_v ~ 860,000) in cyclohexane, were used to attempt to obtain the correlation. The V-100 solutions were not used because they were not drag reducing.

The …

The Anodic Oxidation Of Crotonic Acid In Basic Solutions, Richard C. Porter

Masters Theses

"The purpose of this study was to investigate the anodic oxidation of crotonic acid in basic solutions. Potassium hydroxide solutions of pH 12.3 and KOH-K₂CO₃ solutions of pH 11.5 and 10.5 were used. The investigation was carried out on platinized-platinum anodes at 80°C.

Experimental studies were conducted to determine the effects of crotonic acid concentration, pH, and temperature on the current. Faradaic efficiency was determined by analysis of CO₂ produced and was approximately 100 per cent.

The results were interpreted in terms of a mechanism having the following characteristics:

1. The first electron transfer is the rate …