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The Optimization Of A Catalytic Methanol Reactor, Peter Wrampe Jun 1968

The Optimization Of A Catalytic Methanol Reactor, Peter Wrampe

Theses

The development of a computer program which determines the minimum space time of the methanol synthesis reactants is presented. Also, the optimum temperature profile along the catalytic reactor was predicted for a desired conversion at a given operating pressure, feed composition, and catalyst effectiveness factor.

The equilibrium conversion of methanol was determined at various reaction parameters. Rates of reaction were ascertained and maximized with respect to temperature for various conversions and given reaction parameters. The results, along with those obtained when the design equation was numerically integrated, were compared to published data. Equations were established for various sets of published …


Realization Of Transfer Impedances Using Distributed Rc Elements In A Common Ground Linvill Configuration, Walter Woronka Jun 1968

Realization Of Transfer Impedances Using Distributed Rc Elements In A Common Ground Linvill Configuration, Walter Woronka

Theses

One of several synthesis procedures available for the realization of a transfer admittance is that of Linvill. This synthesis procedure employs an active element, a negative impedance converter (NIC), to shift the poles of passive immittance functions from the negative real axis into the complex plane to realize the desired transfer immittance function.

The Linvill synthesis procedure is extended to networks containing cascaded distributed RC elements and the conditions which must be satisfied to realize a transfer impedance using these distributed elements are defined.


The Effect Of Nitrilotriacetic Acid Upon The Biodegradability Of Linear Alkyl Benzene Sulfonate, John D. Mckenna Jun 1968

The Effect Of Nitrilotriacetic Acid Upon The Biodegradability Of Linear Alkyl Benzene Sulfonate, John D. Mckenna

Theses

The effects of trisodium nitrilotriacetate (SKTA) and sodium tipolyphosphate (STPP) upon the biological degradation of linear alkyl benzene sulfonate (LAS) ware experimentally investigated by the chemical oxygen demand and methylene blue methods. It was found that when STPP was present with LAS, the degradation of the LAS was better than when alone in solution. It was also found that LAS in solution with SN TA was less degradable than LAS alone. The benzene ring of the MS appeared to degrade after most of the linear portion of the chain had already been degraded.


Effect Of Column Diameter On The Frequency Response Of Water Fluidized Beds, Edward C. Maiuro Jun 1968

Effect Of Column Diameter On The Frequency Response Of Water Fluidized Beds, Edward C. Maiuro

Theses

The effect of column diameter on the frequency response of water fluidized beds was investigated.

Studies were made on four columns ranging from four to ten inches in diameter. Water was used to fluidize the beds which consisted of spherical glass beads .0185 inches in diameter. A trace solution of sodium chloride was sinusoidally introduced into the beds. Inlet and outlet concentrations were continuously measured by an electrical conductivity recorder. Separate frequency response tests were conducted on the inlet calmning section in an attempt to obtain the frequency response of this region alone. Results of the tests were expressed as …


The Plasticization Of 4-Methyl-Pentene-1 (Tpx-Rt-D30) Polymer With Petroleum Jelly, Joseph P. Mccann Jun 1968

The Plasticization Of 4-Methyl-Pentene-1 (Tpx-Rt-D30) Polymer With Petroleum Jelly, Joseph P. Mccann

Theses

The properties of TPX-RT-D30 (4-methyl-pentene-1 polymer) have been changed by blending petroleum jelly with the polymer. The polymer was blended in a Brabender apparatus with up to 40% by weight petroleum jelly (P.J.) at 270°C, pressed and quenched in water. Samples were die cut for the various tests. The polymer tensile properties (ASTM-638-64T) showed both a break and yield value in all ratios as compared to only a break value for the TPX-RT polymer. Breaking strength ranged from 4000 psi for pure TPX-RT down to 1000 psi at 40% P.J., with a leveling point of 2000 psi at 15% P.J. …


Reliability Considerations For Communication Satellites, Frank Polizzi May 1968

Reliability Considerations For Communication Satellites, Frank Polizzi

Theses

A detailed program covering all phases of reliability for a communication satellite was presented. In long mission programs such as this one, reliability is the prime consideration in assuring a successful accomplishment of the stringent goals set forth. Reliability principles and methods were incorporated in delineating each major task in the program. These principles and methods not only aided the reliability personnel in performing their duties better, but also assisted the design group, manufacturing personnel, and the testing and evaluation group in performing their jobs efficiently by being aware and knowledgeable of reliability engineering.

Various reliability disciplines were imposed, as …


A Study Of The Properties Of The Biconical Antenna, Kurt Frank Hafner Jr. May 1968

A Study Of The Properties Of The Biconical Antenna, Kurt Frank Hafner Jr.

Theses

Expressions are found for the fields produced by TM and TEM modes along a finitely conducting biconical antenna. Expressions are also found for the TM and TEM fileds along a biconical antenna having a lossy dielectric coating. It is shown that the antenna losses produce an anntenuation of the the fields along the antenna. It is found that because there is a dispersion of the fields along the biconical antenna, the attenuation produced by the losses is, in genaral, not characterized by simple exponential.

A solution is obtained for the fields of the TEM wave along a biconical antenna coated …


Transition From Laminar To Turbulent Flow For Dilute Guar Gum Solutions, Martin L. Palmer May 1968

Transition From Laminar To Turbulent Flow For Dilute Guar Gum Solutions, Martin L. Palmer

Theses and Dissertations

Solutions of many natural and synthetic polymers have been found to reduce turbulent friction losses in flow through pipes. The basic mechanism causing these reductions is not entirely understood although two general theories have been advanced.


Study Of Sheltered Evaporation In Colombia, Guillermo Pardo-Bonilla May 1968

Study Of Sheltered Evaporation In Colombia, Guillermo Pardo-Bonilla

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Equations, tables, and graphs for estimating evaporation from sheltered evaporimeters were developed, based on data from 20 stations in Colombia.

Computer programs and plottings were the basic tools to work out the equations. The form of the simplified final equation is

Ev = kCVPDCT

in which

    • Ev is the evaporation in millimeters per day
    • K is a constant
    • CVPD is the vapor pressure deficit coefficient
    • CT is the temperature coefficient

Statistical parameters were determined to compare the measured evaporation with the Christiansen-Guillen formula and the newly developed formulas.


Electric Arc Welding Of Gray Cast Iron Without Preheating, Ramon Prestwich May 1968

Electric Arc Welding Of Gray Cast Iron Without Preheating, Ramon Prestwich

Theses and Dissertations

Cast irons are iron-carbon alloys with greater than 1.7% carbon. Although white, malleable and ductile cast irons are used extensively for casting work, this study is concerned with only the gray cast irons.


Automation In The Design Of Asynchronous Sequential Circuits, Richard T. Smith, James H. Tracey, W. L. Schoeffel, G. K. Maki Apr 1968

Automation In The Design Of Asynchronous Sequential Circuits, Richard T. Smith, James H. Tracey, W. L. Schoeffel, G. K. Maki

Electrical and Computer Engineering Faculty Research & Creative Works

Sequential switching circuits are commonly classified as being either synchronous or asynchronous. Clock pulses synchronize the operations of the synchronous circuit. The operation of an asynchronous circuit is usually assumed to be independent of such clocks. The operating speed of an asynchronous circuit is thus limited only by basic device speed. One disadvantage of asynchronous circuit design has been the complexity of the synthesis procedures for large circuits.


The Influence Of Ionic Polarizability On The High Temperature Mechanical Properties Of Ionic Crystals, William A. Johnston Mar 1968

The Influence Of Ionic Polarizability On The High Temperature Mechanical Properties Of Ionic Crystals, William A. Johnston

Masters Theses

No abstract provided.


West Midlands Development : Erosion Prevention And Control, G W. Spencer Jan 1968

West Midlands Development : Erosion Prevention And Control, G W. Spencer

Journal of the Department of Agriculture, Western Australia, Series 4

THE prevention of soil erosion is essentially a matter of using each soil according to its potential, and treating it according to its needs.

Good land use and sound management practices are the best preventive measures.


West Midlands Development : Development Techniques, Department Of Agriculture, Western Australia Jan 1968

West Midlands Development : Development Techniques, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

Most clearing in the West Midlands is carried out by chaining, though the method chosen will depend on the country being cleared and on the resources of the farmer.


Concrete In Dairies, D Roger Buchanan Jan 1968

Concrete In Dairies, D Roger Buchanan

Journal of the Department of Agriculture, Western Australia, Series 4

PRIME requirements for exposed concrete surfaces in dairies are that they should be easily cleansed and should not deteriorate in contact with milk and milk products.

In milking stalls, animal races and on loading platforms hardwearing surfaces which offer good foothold are also necessary.


Linear Programming With Random Requirements, Nak Je Kim Jan 1968

Linear Programming With Random Requirements, Nak Je Kim

Reports

Linear programming was first developed by George B. Dantzig, Marshall Wood, and associates of the U.S. Air Force, in 1947. At that time, the Air Force organized a research group under the title of project SCOOP (Scientific Computation of Optimum Programs). This project contributed to the developing of a general interindustry model based on the Leontief input-output model, the Air Force programming and budgeting problem, and the problems which involved the relationship between two-person zero sum games and linear programming. The result was the formal development and application of the linear programming model. This project also developed the simplex computational …


Influence Of Continuous Precipitation Upon The Growth Kinetics Of The Cellular Reaction In An Al-Ag Alloy, H. I. Aaronson, J. B. Clark Jan 1968

Influence Of Continuous Precipitation Upon The Growth Kinetics Of The Cellular Reaction In An Al-Ag Alloy, H. I. Aaronson, J. B. Clark

Materials Science and Engineering Faculty Research & Creative Works

The influence of the prior formation of a continuous precipitate upon the growth kinetics of the cellular reaction has been evaluated in an Al-17.9 wt. % Ag alloy. The continuous precipitate, in the form of intragranular plates of the γ′ transition phase, was shown to have reduced the upper bound of the driving force for the cellular reaction from the silver content of the untransformed alloy to that corresponding to the coherent solvus. When this reduction (≥ 98 %) is taken into account, the growth of cells is found to be controlled by cell boundary rather than by volume diffusion …


Numerical Integration Of Shell Equations Using The Field Method, Pravin R. Ghael Jan 1968

Numerical Integration Of Shell Equations Using The Field Method, Pravin R. Ghael

Masters Theses

"In this work field equations are introduced to numerically solve the six linear differential equations which determine the displacements and stress resultants for thin elastic shells with axially symmetric loadings. With the applications of the field equations to the analysis of symmetric shells, the two-point boundary-value problem is formulated in terms of twelve first-order ordinary differential equations with boundary conditions at only one point. These equations are solved by using a forth [sic]-order Runge_kutta integration formula. Three problems whose solutions are known have been evaluated to check the accuracy of the field equation method. These are: (1.) Simply-supported, thin circular …


Isotope Effect Of Interstitial Diffusion Of Carbon In A Dilute Fe-Si Alloy, Edward T. Yen Jan 1968

Isotope Effect Of Interstitial Diffusion Of Carbon In A Dilute Fe-Si Alloy, Edward T. Yen

Masters Theses

"The isotope effect of carbon interstitial diffusion in a Fe-2.75at%Si alloy has been measured at -3.10°C using the disaccommodation technique. The disaccommodation has been analyzed in terms of two relaxation processes which are discussed on the basis of the reorientation mechanism of carbon interstitials at Fe-Fe sites and Fe-Si sites respectively. The ratios of the relaxation times [tau]₁₃/[tau]₁₂ are 1.0382 for the former and 1.0072 for the latter relaxation process. This result is discussed on the basis of many-body reaction rate theory"--Abstract, page ii.


Construction Time And Cost Control Using The Ibm Project Management System/360, James Donald Bailey Jan 1968

Construction Time And Cost Control Using The Ibm Project Management System/360, James Donald Bailey

Masters Theses

"The object of this investigation was to determine the advantages or disadvantages involved in the use of the IBM Project Management system/360 as a time and cost control tool as compared to the methods presently used by construction contractors in the small to medium size range.

The methods used by three construction contractors were investigated in order to acquire a sample of methods presently used.

It was determined from the investigation that a number of advantages could be obtained which would provide better control of a construction project.

It was also decided that a detailed investigation concerning the cost of …


A Fluidic Liquid Level Control System, Vinod Kumar Verma Jan 1968

A Fluidic Liquid Level Control System, Vinod Kumar Verma

Masters Theses

"The prime objective of this investigation was to design and construct a working "Fluidic liquid level control system", and to make a functional study of the characteristics of the devices employed therein. A working model of a "fluidic liquid level control system" is developed and experimental data is collected to describe the functional characteristics of the fluidic circuits employed. The system contains a pressure sensitive, variable frequency oscillator; appropriate demodulation stages to convert the variable frequency alternating signal into a varying non-alternating signal; and on-off control elements in the final stages"--Abstract, page ii.


The N-Wire Exponential Transmission Line, Vernon Ray Stanley Jan 1968

The N-Wire Exponential Transmission Line, Vernon Ray Stanley

Masters Theses

"This paper deals with the n-wire exponentially tapered transmission line. A characteristic impedance is defined, and the results of terminating in this impedance are investigated. A very long line and the condition of no reflections are considered, and the conclusions are compared. Finally, three specific 3-wire line problems are worked with a characteristic impedance termination and a unit step input"--Abstract, page ii.


An Unsteady-State Method For Determining The Thermal Conductivity Of Materials, Richard H. Bulmer Jan 1968

An Unsteady-State Method For Determining The Thermal Conductivity Of Materials, Richard H. Bulmer

Masters Theses

"Originally this work was initiated to develope [sic] a method for measuring the thermal diffusivity and thermal conductivity of metals. Due to the characteristics of the method and the equipment used, it was concluded that the technique is not suitable for materials of high conductivity. However, results show that the apparatus is valuable for the determination of the thermal diffusivity of relatively poor heat conductors. The favorable characteristics of the method are its rapidity and basic simplicity"--Abstract, page ii.


Pressure Welding Of Continuously Cast Nodular Iron, Gerald W. Wille Jan 1968

Pressure Welding Of Continuously Cast Nodular Iron, Gerald W. Wille

Masters Theses

"The objective of this study was to determine the feasibility of using pressure welding as a joining technique for swaged nodular iron.

Test pressure welds were produced with swaged continuous cast nodular iron at temperatures between 1750⁰F and 2050⁰F with welding pressures between 15,900 psi and 51,400 psi using an induction coil to heat the weld zone.

Pressure welds of greater strength than the as-received nodular iron were produced by swaging the material before welding. The optimum welding parameters were a temperature of 2050⁰F with a welding pressure of 46,700 psi.

On the basis of these tests it is concluded …


Diffusion Coefficients Of D-Glucose In Aqueous Carboxymethylcellulose And Carboxypolymethylene Solutions, Audrey Liu-Mei Huang Jan 1968

Diffusion Coefficients Of D-Glucose In Aqueous Carboxymethylcellulose And Carboxypolymethylene Solutions, Audrey Liu-Mei Huang

Masters Theses

"A microinterferometric method was used to determine the concentration profiles in the infinite field unsteady state diffusion of D-Glucose in aqueous polymer solutions. Pseudo binary diffusion coefficients were determined as a function of reduced concentration both with and without the effect of liquid volume change during diffusion being considered. The systems studied were D-Glucose in aqueous Carboxymethylcellulose and D-Glucose in aqueous Carboxypolymethylene solutions. Solute concentration ranged from nearly zero to about 9% by weight D-Glucose in the aqueous polymer solutions"--Abstract, page ii.


Coupled Transport Of Heat And Mass In Laminar Tube Flow, Lung-Mau Huang Jan 1968

Coupled Transport Of Heat And Mass In Laminar Tube Flow, Lung-Mau Huang

Masters Theses

"The object of this investigation is to study the mutual dependence of heat and mass transport in laminar and hydrodynamically developed tube flow. Consideration is given to gas flow through a tube whose wall is coated with a sublimable materials so that heat and mass transfers take place between the wall and the flowing gas stream. The tube wall is thermally insulated from the external environment, with the result that the latent heat required by the sublimation process at the wall is supplied solely by convective transfer from the gas. The analysis of the problem requires simultaneous solution of the …


Measurement Of Demagnetizing Factor Of Ring-Core, Subhashchandra Chimanlal Patel Jan 1968

Measurement Of Demagnetizing Factor Of Ring-Core, Subhashchandra Chimanlal Patel

Masters Theses

"A method has been presented to measure the demagnetizing factor of ring-cores. First the incremental apparent permeability and the incremental true permeability were measured at different degrees of saturation and then the demagnetizing factor was determined from those results. The cores used were tape would ring-cores of mean length of 8.0 cm. The method was found suitable for cores with 1/4 mil or thicker tape, but was in question for the 1/8 mil tape core tested"--Abstract, page ii.


A Numerical (Matrix) Solution For The Vibration Frequencies And Modes Of A Nonuniform Rectangular Plate With Arbitrary Edge Conditions, F. David Utterback Jan 1968

A Numerical (Matrix) Solution For The Vibration Frequencies And Modes Of A Nonuniform Rectangular Plate With Arbitrary Edge Conditions, F. David Utterback

Masters Theses

"The material presented in this thesis is designed to provide the practicing engineer with a practical, approximate method of solution for the increasingly important problem of plate vibrations. The technique presented herein is basically an application of the use of generalized coordinates to describe the elastic and inertial properties of a finite element representation of a nonuniform rectangular plate. The plate will be idealized by utilizing a modification of the grid work technique developed by Hrennifkoff as a lattice work of interconnecting beams. By employing the elastic displacements as generalized coordinates, the only required compatibility conditions are that the displacements …


An Experimental Method Of Determining The Thermal Accommodation Coefficients Of Metallic Surfaces, Raymond John Dethorne Jan 1968

An Experimental Method Of Determining The Thermal Accommodation Coefficients Of Metallic Surfaces, Raymond John Dethorne

Masters Theses

"In the free molecule regime, Knudsen number greater than 10, heat is transferred from a solid by radiation and conduction. The ability of a surface to emit radiant energy is governed by a surface property called emittance while the surface property which apparently regulates the amount of heat transferred by conduction is called the thermal accommodation coefficient. This thesis presents the results of an experimental investigation to determine a relationship between these two properties, emittance and thermal accommodation coefficient. A test apparatus was constructed to measure both the radiation and conduction contributions between two concentric cylinders. cylinders of aluminum and …


Spacing Of Explosive Charges, Calvin J. Konya Jan 1968

Spacing Of Explosive Charges, Calvin J. Konya

Masters Theses

"It is generally believed that the spacing of simultaneously initiated collar primed multiple charges is not dependent on the charge length. The stresses generated by explosive charges have been assumed to propagate through a material in a cylindrical manner. this assumption implied that the stress generated in any plane along the charge diameter would have been uniform in magnitude and direction. A finite explosive velocity along with a conical stress wave causes the stresses near the collar to differ from those farther down the column. for this reason, the spacing of charges would be dependent on charge length. An experimental …