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Mass And Heat Transfer Through Nonwettable Porous Membranes, Chung-Liang Yeh Jan 1969

Mass And Heat Transfer Through Nonwettable Porous Membranes, Chung-Liang Yeh

Doctoral Dissertations

"Evaporation of water through nonwettable porous membranes has been studied under various pressures with various membrane thicknesses. The results of previous investigations at 1 atmosphere have been correlated into one equation for mass transfer resistance which has also been found to fit approximately new data obtained of 1.5, 2, and 3 atmospheres in this investigation. In the new data fluxes varied from 0.064 to 0.691 lb./ft.²/hr. through glass fiber-Teflon membrane from 0.02 to 0.08 inch in thickness. Temperatures ranged for 80 to 260°F. A more theoretical equation has been developed to explain variations from the equations based on 1 atmosphere …


A Finite Element Method For Geometrically Nonlinear Large Displacement Problems In Thin, Elastic Plates And Shells, Ronald August Melliere Jan 1969

A Finite Element Method For Geometrically Nonlinear Large Displacement Problems In Thin, Elastic Plates And Shells, Ronald August Melliere

Doctoral Dissertations

"A finite element method is presented for geometrically nonlinear large displacement problems in thin, elastic plates and shells of arbitrary shape and boundary conditions subject to externally applied concentrated or distributed loading. The initially flat plate or curved shell is idealized as an assemblage of flat, triangular plate, finite elements representing both membrane and flexural properties. The 'geometrical' stiffness of the resulting eighteen degree-of-freedom triangular element is derived from a purely geometrical standpoint. This stiffness in conjunction with the standard small displacement 'elastic' stiffness is used in the linear-incremental approach to obtain numerical solutions to the large displacement problem. Only …


Anodic Oxidation Of Pure And D.S. (Dispersion Hardened) Lead In Sulfuric Acid Solutions, Rafael San Martin Aldazabal Jan 1969

Anodic Oxidation Of Pure And D.S. (Dispersion Hardened) Lead In Sulfuric Acid Solutions, Rafael San Martin Aldazabal

Masters Theses

"The anodic oxidation of pure and dispersion hardened lead in 1 N H₂SO₄ was studied potentiostatically in the range - 0.28 to 2.0 volts (SHE). The anode surfaces were observed at various stages on a scanning electron microscope and x-ray diffraction techniques were used to determine the phases present. It was established that by oxidation up to 0.25 v only PbSO₄ is obtained. At potentials between 0.25 and 1.57 v, PbO (tetragonal) is formed beneath the lead sulfate layer. At potentials above 1.57 up to 2.0 v, a layer of ßPbO₂ forms in the outermost part of the anode underlying …


Establishment Of A Torsion Pendulum And Its Evaluation, Ashwin Kantilal Ghatalia Jan 1969

Establishment Of A Torsion Pendulum And Its Evaluation, Ashwin Kantilal Ghatalia

Masters Theses

"A torsion pendulum apparatus has been constructed. The pendulum has been evaluated by studying the Zener relaxation in α brass. Three wire specimens of commercial alloy of Cu-Zn were used and the value of log decrement has been obtained by the method of free decay of the oscillations. The known Zener peak was observed"--Abstract, page ii.


Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal Jan 1969

Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal

Masters Theses

"Thermal fatigue is a form of surface failure produced by repeated thermal stresses and is the main cause of die retirement in the die casting industry. A general review of the fundamental and practical aspects of thermal fatigue as encountered in the dies, based on earlier published work, is given and preliminary experiments in an effort to set up a suitable method of testing to study this phenomenon are then described. In the present technique developed to create the thermal conditions experienced by a die steel in aluminum die casting, a small portion of one face of a cylindrical test-piece …


Static And Dynamic Instability Analysis Of Rigid Frames With Timoshenko Members, Carlton Lee Smith Jan 1969

Static And Dynamic Instability Analysis Of Rigid Frames With Timoshenko Members, Carlton Lee Smith

Masters Theses

"In this thesis, a technique has been developed to determine the natural frequencies of plane rigid frames with the consideration bending, shear deformation, rotatory inertia, and internal axial forces. The internal forces are functions of the instability load of the vibrating system for which the effects of bending and shear deformation on the stability of this structure are considered. For the sake of completeness, the matrix formulations for the dynamic or stability analysis of a rigid frame are given. The stiffness matrices of these formulations are then derived. The influence of shear deformation, rotatory inertia, and internal axial force is …


Fast Neutron Effects On Transistor Scattering Parameters, David Leslie Gray Jan 1969

Fast Neutron Effects On Transistor Scattering Parameters, David Leslie Gray

Masters Theses

"It has not been possible in the past to characterize a transistor or other semiconductor device with regard to its performance in a fast neutron (E>10keV) environment when the device is operated at high (>100 MHz) frequencies. Using the scattering (s-) parameter concept, which regards a device as a two-port "black box", a full characterization of the trends in the neutron bombarded high-frequency performance of a typical transistor can be made. Scattering parameters are not only an accurate means of describing the high-frequency performance of any device, but are now reasonably easily measured with the advent on the …


A Synthesis Procedure Of Distributed Rc Parameter Networks, Chun-Ming Wen Jan 1969

A Synthesis Procedure Of Distributed Rc Parameter Networks, Chun-Ming Wen

Masters Theses

"Synthesis procedures for driving-point functions and transfer functions in the w plane are developed in this thesis. For driving-point functions and transfer functions which are single-valued in s, where s is the complex frequency variable, the synthesis procedures were derived from the extension of the O'Shea's trasformation [sic]. For the transfer functions which satisfy the stability theorem in the w plane, a synthesis procedure is developed by using a distributed-lag element (DL) or a uniform distributed RC (UDRC) network with matched terminations"--Abstract, page ii.


A Study Of Low-Cost Heat Exchangers For Desalination, Chin-Tsai Lin Jan 1969

A Study Of Low-Cost Heat Exchangers For Desalination, Chin-Tsai Lin

Masters Theses

"This investigation was proposed to search for simple and inexpensive but effective heat exchangers for the recovery of heat in water desalination by evaporation through non-wettable porous membranes. Aluminum was chosen as the material for constructing the heat exchangers. Various fluted arrangements and one plate type arrangement were chosen to increase heat transfer coefficients and conserve material. Equations correlating the heat transfer coefficients to temperatures and flow rates have been suggested for estimating the overall heat transfer coefficient at different conditions. The results of economic calculations indicate that the cost per unit transfer area of the exchangers in this investigation …


Design, Construction, And Initial Experiments With High Hydrostatic Pressure Extrusion Device, Edward Moniz Jorge Jan 1969

Design, Construction, And Initial Experiments With High Hydrostatic Pressure Extrusion Device, Edward Moniz Jorge

Masters Theses

"The purpose of this study was to design and operate equipment with which the study of polymer extrusion would be possible at hydrostatic pressures up to 50,000 psi. By hydrostatic pressure is meant the pressure of the region of the extrudate. A study of the effects of back pressure on the extrusion of silicone gum was attempted--Abstract, Page ii.


The Influence Of Several Factors On The Rate Of Secondary Compression Of Soil, William Joel Green Jan 1969

The Influence Of Several Factors On The Rate Of Secondary Compression Of Soil, William Joel Green

Masters Theses

"This research program has been undertaken to study the influence of load increment ratio, temperature, and sample thickness on Cα (rate of secondary consolidation) for a high organic content and low organic content soil. Consolidation equipment was designed to produce constant temperatures both above and below ambient, and to accommodate both 3/4 and 1 1/2 inch thick samples. Samples were molded into oedometer rings at the liquid limit. It was found that Cα was independent of the sample thickness and load increment ratio for both the high organic and low organic soils. The influence of temperature on Cα was found …


A Continuous Method For Determination Of The Evaporation Rate Of Zinc, Paul Alan O'Neill Jan 1969

A Continuous Method For Determination Of The Evaporation Rate Of Zinc, Paul Alan O'Neill

Masters Theses

"A method for determination of the evaporation rate of zinc using a continuous recording balance has been devised. Tests were carried out under an inert gas over the range 600°C to 750°C with a total pressure of 1 atmosphere. It was found that the rate of evaporation doubled with an increase of 50°C in this range. Scanning electron microscope photographs show the crystalline nature of the condensate and the presence of a thin oxide layer on some solidified test samples. This oxide layer reduced the rate of evaporation by retarding the zinc vapor escape from the evaporating surface"--Abstract, Page iii.


Additional Magnetic Disaccommodations In Ternary Iron Base Alloys, R. H. Graham, Manfred Wuttig Jan 1969

Additional Magnetic Disaccommodations In Ternary Iron Base Alloys, R. H. Graham, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.


A Theoretical Analysis Of The Free Vibrations Of A Clamped Circular Plate With Damping, Bhalchandra Krishnaji Vaidya Jan 1969

A Theoretical Analysis Of The Free Vibrations Of A Clamped Circular Plate With Damping, Bhalchandra Krishnaji Vaidya

Masters Theses

"A theoretical analysis of the free vibrations of a clamped circular plate was undertaken. The effects of transverse shear were considered for application to relatively thick plates in which there exist sharp transients and frequencies corresponding to higher modes. The method adopted by R. D. Mindlin was used to develope [sic] the differential equation of motion for the plate. The damping effect due to the resistance of the medium in which the plate vibrates was also considered. This damping was assumed to be due to the generation of pressure waves caused by the displacement of the plate...Since the solution requires …


Computer-Aided Design Of Lossless Non-Uniform Transmission Lines, Larry Lee Wesner Jan 1969

Computer-Aided Design Of Lossless Non-Uniform Transmission Lines, Larry Lee Wesner

Masters Theses

"A numerical iterative design technique is presented for the synthesis of lossless non-uniform transmission lines. A variational approach is used to minimize an error functional to which the system and boundary equality constraints have been adjoined by Lagrangian multipliers. The resultant network optimization conditions lead to an iterative scheme requiring analysis of the non-uniform line, analysis of an adjoint system and calculation of the error gradient in parameter space. A steepest descent procedure is used to optimize parameter values. Finite difference equations are used to provide an approximation model for implementation on the digital computer. A design example and a …


Basic Design Of Mosfet, Four-Phase, Digital Integrated Circuits, Earl Morris Worstell Jan 1969

Basic Design Of Mosfet, Four-Phase, Digital Integrated Circuits, Earl Morris Worstell

Masters Theses

"MOSFET is defined as metal oxide semiconductor field-effect transistor. The integrated circuit design relates strictly to logic and switching circuits rather than linear circuits. The design of MOS circuits is primarily one of charge and discharge of stray capacitance through MOSFETS used as switches and active loads. To better take advantage of the possibilities of MOS technology, four-phase (4[phi]) circuitry is developed. It offers higher speeds and lower power while permitting higher circuit density than does static or two-phase (2[phi]) logic. Equations are developed that apply directly to the design of four-phase logic along with examples of circuitry that show …


Some Aspects Of Aerated Open-Channel Flow At Shallow Depths And Low Velocities, D. L. Fread Jan 1969

Some Aspects Of Aerated Open-Channel Flow At Shallow Depths And Low Velocities, D. L. Fread

Masters Theses

"This study is concerned with the effect of entrained air bubbles on the open-channel hydraulics of water flowing at low velocities. The air bubbles are introduced into the flowing water by injecting diffused compressed air along the channel bottom. The variations of the velocity profile and velocity distribution energy coefficient of aerated and nonaerated flow are discussed. Empirical equations have been determined for the air concentration and increased depth of flow or "bulking" of the aerated open-channel flow. The investigation revealed a significant increase in the Manning roughness coefficient and the related Darcy friction factor for aerated flow relative to …


The Electrodeposition Of Zinc; Changes In Current Efficiency And Surface Structure Resulting From Various Addition Agents, Haruhisa Fukubayashi Jan 1969

The Electrodeposition Of Zinc; Changes In Current Efficiency And Surface Structure Resulting From Various Addition Agents, Haruhisa Fukubayashi

Masters Theses

"An examination of the surface structure of zinc electrodeposited from an acid-sulfate solution was made by scanning electron microscopy techniques. The current efficiencies were also determined, to a lesser extent, in order to correlate the results with the surface structures. Commercial and pure zinc oxide were used to prepare the neutral zinc sulfate solutions. The starting solutions were in a range of acid and zinc concentrations commonly used in commercial practice. Changes in morphology resulting from addition agents such as animal glue, gum arabic, and sodium silicate are compared"--Abstract, page ii.


Effect Of Hydrostatic Pressure On Anelastic Stress Relaxation In A Mixed-Alkali Silicate Glass, Young-Gil (Gilbert Y.) Kim Jan 1969

Effect Of Hydrostatic Pressure On Anelastic Stress Relaxation In A Mixed-Alkali Silicate Glass, Young-Gil (Gilbert Y.) Kim

Masters Theses

"The effect of hydrostatic pressure on the anelastic stress relaxation of a mixed-alkali silicate glass (0.05 Na₂O, 0.95 K₂O, 3 SiO₂) was studied at 75°C between ambient pressure and 6 kbar. The activation volume of diffusion was found to be - 4.2 cm³/mole. It is proposed that a reequilibration of the defect population at pressure gives rise to the negative activation volume of diffusion"--Abstract, page ii.


A Comparison Of Lumped Parameter Models Commonly Used To Describe One-Dimensional Vibration Problems, Suresh Kumar Tolani Jan 1969

A Comparison Of Lumped Parameter Models Commonly Used To Describe One-Dimensional Vibration Problems, Suresh Kumar Tolani

Masters Theses

"Three lumped parameter model representations of the one-dimensional uniform continuous system in a vibration state are examined. The exact (continuous) solutions were used as a reference to evaluate the accuracy of the results obtained via these discrete element models. The model comparisons, carried out for both the principal modes and the systems under forced excitations, are based on the maximum strain energy. The effect of varying the number of segments in the model representation showed improvement in approximating the exact strain energy solution as the number of segments was increased. In general, the results of the model comparisons based on …


Free-Convection Heat Transfer From An Inclined Heated Flat Plate In Air, S. C. Yung, R. B. Oetting Jan 1969

Free-Convection Heat Transfer From An Inclined Heated Flat Plate In Air, S. C. Yung, R. B. Oetting

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.


Mass And Heat Transfer Relations In Evaporation Through Porous Membranes, Marshall E. Findley, V. V. Tanna, Y. B. Rao, C. L. Yeh Jan 1969

Mass And Heat Transfer Relations In Evaporation Through Porous Membranes, Marshall E. Findley, V. V. Tanna, Y. B. Rao, C. L. Yeh

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study concerns rates of evaporation and mass transfer of water vapor from a heated salt solution through a water repellent porous membrane to a cooled water condensate. This transfer is a result of temperature differences and corresponding vapor pressure differences across the membrane. Three groups of experiments were carried out which indicate that the major factor influencing the rates of transfer is diffusion through a stagnant gas in the membrane pores. However, an equation considering film heat transfer coefficients, membrane thermal conductivity, and an empirical correction based on temperature driving force appears to be necessary for representing all the …


On The Influence Of Surface Roughness On The Determination Of Diffusion Constants, Manfred Wuttig Jan 1969

On The Influence Of Surface Roughness On The Determination Of Diffusion Constants, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.


Dynamic Response Of A Gyrocompass, Subhash Govind Kelkar Jan 1969

Dynamic Response Of A Gyrocompass, Subhash Govind Kelkar

Masters Theses

"A gyrocompass with three degrees of freedom is studied and an attempt made to solve the exact equations of motion numerically. The equations are obtained by using the Lagrange formulation of the problem. The kinetic energy and the potential energy of the system are determined from the energies of the various components. These are then substituted into Lagrange's equation to obtain the three equations of motion for the three angular coordinates. As few restrictive assumptions as possible are made during this development. From these exact equations of motion an approximate analytical solution is obtained by making several assumptions and then …


Criteria For Planning A Mobile Home Park Development In Rural Areas, Richard Euguene Sharp Jan 1969

Criteria For Planning A Mobile Home Park Development In Rural Areas, Richard Euguene Sharp

Masters Theses

"The object of this study was to determine the possibility of developing a mobile home park as a partial solution to the problem of inadequate housing in rural communities. The investigation involved the study of modern mobile homes and mobile home parks, mobile home dwellers, and the social and economic aspects of mobile home living. It was suggested that a properly designed and managed mobile home park can provide a satisfactory location for the placement of mobile homes. The small down payment and low monthly payments associated with purchasing a mobile home, along with the inherent mobility of mobile home …


The Anodic Dissolution Of Molybdenum In Acid Sulfate Solutions, Ching-Kuo Chen Jan 1969

The Anodic Dissolution Of Molybdenum In Acid Sulfate Solutions, Ching-Kuo Chen

Masters Theses

"The world's resources of metals are decreasing. Due to this and the cost of replacing corroded materials, it has come to be realized that prevention is better than cure. The increasing demand for molybdenum and molybdenum alloys has stimulated a great amount of research into the corrosion characteristics of these materials. The result of such research has assisted in the development of suitable molybdenum alloys and protective coatings to retard corrosion. When a molybdenum anode and a suitable cathode are immersed in an oxygen-free electrolyte and are connected to a direct current power source, molybdenum is dissolved. This process is …


The Anodic Dissolution Of Molybdenum In Alkaline Solutions, Chen Hwei Chi Jan 1969

The Anodic Dissolution Of Molybdenum In Alkaline Solutions, Chen Hwei Chi

Masters Theses

"Details concerning the anodic dissolution of many metals in various solutions are still unknown. Discrepancies are found between the actual weight-loss of an electrode and that calculated from coulometric data. The purpose of this investigation was to study the anodic dissolution of molybdenum (Mo) in basic solutions to determine the apparent valence of Mo ions going into solution, the nature of any surface films formed during dissolution, and the polarization behavior. Three electrolytes were used: 1 N potassium hydroxide (pH = 13.6), 0.667 N potassium carbonate (pH = 11.5), and potassium carbonate-potassium sulfate mixture (pH = 9.5). chloride ion additions …


The Use Of Turbulence Energy Equation In Boundary Layer Study, Ro-Chi Tai Jan 1969

The Use Of Turbulence Energy Equation In Boundary Layer Study, Ro-Chi Tai

Masters Theses

"A turbulent boundary layer problem has been studied analytically and compared with an available experiment in the literature. Correlations of the experimental data were made to investigate the validity of the commonly used empirical relations on turbulent shear stresses. It was found that the model which related the local turbulent shear stress linearly with the local turbulent kinetic energy, as used by Bradshow et. al., appeared to be most reasonable. combining this model with the expression of turbulent viscosity given by Boussinesq, it was then possible to introduce the turbulence-energy equation in addition to the governing equations of continuity and …


Analog Simulation Of Mass Transfer In Droplets With Turbulent Internal Circulation, Jeffrey Tsai-Hwa Kuo Jan 1969

Analog Simulation Of Mass Transfer In Droplets With Turbulent Internal Circulation, Jeffrey Tsai-Hwa Kuo

Masters Theses

"The object of this thesis is to simulate the Handlos and Baron Model for mass transfer into droplets by using an iterative analog computer in order to obtain eigenvalue and other parameters in a series solution. The eigenvalues λn calculated in this work are compared with the results obtained by Wellek-Skelland using a variational technique and by Patel using numerical approaches on the digital computer. From the analytical series solution, one can calculate the fraction of solute extracted in the droplets as a function of droplet contact time. PACTOLUS, a digital-analog simulator, provides a check on the validity of …


A Digital Technique For Combining Frequency Standards, Lynn James Hawkey Jan 1969

A Digital Technique For Combining Frequency Standards, Lynn James Hawkey

Masters Theses

"A new technique for combining multiple frequency standards into a single timing reference based on the average of the frequency of each input is described. The uniqueness of this approach is that it is an all-digital scheme utilizing delay lines and high-speed logic elements currently available. The present and future applications of combiners are discussed, the requirements are highlighted, several digital solutions are briefly described, and the detailed block diagrams and characteristics of a particular general purpose combiner are presented. It is suggested that the optimum combiner include a stable quartz crystal oscillator with a frequency control feature. The output …