Engineering Commons^™

An Investigation Of Broadband Current Preamplification For Obtaining Simultaneous High-Resolution Energy And Time Information From Nuclear Radiation Detectors, Joe Kenneth Millard

Doctoral Dissertations

In beginning the investigation of low noise current preamplification, noise-performance limitations of existing broadband current-amplifying stages are considered. Dominant noise sources of the general, shuntfeedback amplifier stage having both bipolar and field-effect transistor input devices are discussed. This discussion includes the reasons why optimum noise performance from this amplifier stage requires unavoidable signal integration. The integrating shunt-feedback configuration is commonly known as the charge-sensitive preamplifier. Criteria are developed for differentiating the output voltage pulse of the charge-sensitive preamplifier without degrading the signal-to-noise ratio. Subsequently, a new broadband, shunt-feedback amplifier is described having a current gain equal to the ratio of …

Application Of Positive Feedback Techniques To Charge-Sensitive Preamplifiers, Willaim Pinkston Albritton Jr.

Doctoral Dissertations

The application of positive feedback techniques to charge-sensitive preamplifiers for the purpose of improving their performance characteristics and versatility is considered. Improvements in sensitivity of charge gain in input capacitance, preamplifier output pulse rise-time, and ability to terminate long input cables are discussed. In each case, theoretical developments are carried out in order to determine the optimum positive feedback conditions. A practical charge-sensitive preamplifier design is discussed and the effects of applying positive feedback are delineated.

For the experimental preamplifier, the application of positive feedback resulted in a reduction in charge gain sensitivity to input capacitance changes of almost an …

Local Planning Agency Relationships With Councils Of Governments And Development Districts: A General Investigation With A Specific Emphasis On Chattanooga, Tennessee, John Mayes

Masters Theses

The federal government, in an attempt to bring about metropolitan wide problem solving and to foster economic development on a regional scale, has encouraged the establishment of metropolitan councils of governments and economic development districts. These have been given a planning function, financially supported by the federal government. This thesis is a study of how these new planning agencies relate with other planning agencies in areas where their jurisdictions overlap.

This is done in a genera investigation of how the Chattanooga Area Regional Council of Governments and the Southeast Tennessee Development District relate to the local planning agency (the Chattanooga-Hamilton …

Transient Response Of Linear Elastic Structures Determined By The Matrix Exponential Method, William Christopher Terrill Stoddart

Masters Theses

This investigation was undertaken to develop a numerical solution for the transient response of linear, elastic structures based on the matrix exponential solution for first order, linear, constant coefficient differential equations. The investigation was prompted by the need for an economical technique that can be used to analyze multidegree of freedom systems exemplified by piping and structural components associated with nuclear power plants.

A mathematical model characterizing the behavior of linear, elastic structures was developed by using state variables of displacement and velocity. The structure consists of beam elements of uniformly distributed mass, weightless springs, and rigid masses. The stiffness …

Basic Instrumentation Of A Three-Zone Convection Coater Dryer For Calculation Of Heat And Mass Balances, Byron H. Mckinstry

Masters Theses

No abstract provided.

Continuous Interfacial Polycondensation Of Nylon 6-10, Sumer Raj Hundia

Theses

Nylon 6-10 has been prepared by continuous interfacial polycondensation hexamethylenedlamine and sebacoyl chloride in a stirred system. The effect of monomer concentration and stirring on the intrinsic viscosity of the polyamide 6-10 solution in m-cresol was measured.

As stirring (RPM) and monomer increased the intrinsic and the polymer yield through a maximum. Diffusion coefficients (D_AB) for hexamethylenedlamine were for hexamethylenedlamine were and were used for the calculations of j_D factors and K/DAB ratios. A relationship and j_D factors was established by a correlation curve.

Development Of An Apparatus To Obtain Temperature Profiles Of Molten Flowing Polymers, Ismail Kemal Saltuk

Theses

The object of this investigation is to develop and test an apparatus to predict temperature profiles of polymer melts in laminar flow in a heat exchanger, with non-isothermal wall conditions.

A commercial polyethylene melt is pumped at various flow rates through a smooth 0.957 in. I.D. pipe. The entrance temperature of polymer is maintained uniform.

Radially distributed six thermocouples (0.062 in. 0.D.) are placed at 2.5 ft. intervals from the entrance of heat exchanger. Immersion of these probes parallel to the flow direction, reduced the errors due to the conduction of heat from the tube wall to the thermocouple stems. …

Three Dimensional Elastic Wave Propagation In Bodies Of Revolution, Robert S. Pritchard

Mechanical Engineering ETDs

This dissertation describes solution of a class of problems of three dimensional (non-symmetrical) elastic wave propagation in bodies of revolution. The method of analysis is expansion into circumferential modes followed by solution of an approximate numerical scheme using a digital computer. The material constituting the body has been assumed homogeneous, isotropic, linearly elastic and only one mate­rial may appear in the body. A load may be applied either by a pressure blast or by a target body acting over some portion of the boundary. The loading functions may vary around the circumference. Three dimensional wave motion is analyzed by expanding …

The Design Of A Laser Doppler Velocimeter, Marlo R. Anderson

Theses and Dissertations

A relatively new method of measuring local velocity in a fluid stream has been devised which eliminates some of the inherent problems of the traditional methods. This method senses the Doppler shift of light scattered from a laser beam incident on particles suspended in the fluid. The Doppler shift is proportional to the particles (or fluid) velocity. This new technique has several distinct advantages over the more traditional methods of velocity measurement.

A Study Of The Effects Of Some Parameters Of The Galloping Of Electric Transmission Lines, Leland J. Coleman

Theses and Dissertations

Freezing rainstorms coupled with moderate winds have often been observed to cause telephone lines and power transmission cables to begin bouncing up and down. This slow frequency high amplitude oscillation, or galloping as it is sometimes called, can build up to large amplitudes before the oscillation either damps out or persists at some constant amplitude. It has been reported by Edwards and Livingston [1] that the amplitude of galloping on transmission lines has been as large as forty feet. Galloping oscillations occur at relatively low frequencies; from .1 to 1 Hz. [1] near the natural frequency of the suspended cable.

A Dynamic Model Of A Small Manufacturing Company, Abraham John

Theses and Dissertations

A manufacturing company typically has the objective of maximizing the long-term value of its common stock while satisfying its customers. To achieve this, the company might increase the quantity and improve the quality of production. Since the company is operating in a dynamic environment, its policies should be dynamic also, to achieve its objective.

An Optimization Technique Applied To The Determination Of Modal Damping Coefficients, Craig C. Smith

Theses and Dissertations

Although analytical techniques are generally available for the simulation of dynamic systems, often these techniques require a great deal of computer time and storage. This difficulty was vividly pointed out by a previous thesis undertaken in this Department by R. L. Webster (1). Mr. Webster undertook the determination of orthotropic material properties using dynamic response test data from plates. A major difficulty which was encountered was the enormous amount of computer time required for the simulation. This thesis is an investigation of a method which when fully developed, may provide the ability to simulate such systems much more efficiently.

A Data Reduction Technique For Drag-Coefficient Data For Spheres, Stephen Thomas Merrell

Theses and Dissertations

The object of this investigation was to obtain a reliable technique for finding the drag coefficient for a sphere falling at a non-constant velocity through air. And then to apply this technique to the data collected by R. G. Lunnon in 1925^(4)*.

Transport Calculations In Particle-Loaded Media, Gary J. Scrivner

Nuclear Engineering ETDs

Particle-loaded materials are sometimes used for radiation shielding. In many cases shielding calculations, performed with the assumption of a homogeneous medium having the appropriate ratio of particle-to-matrix material, are grossly inadequate. The exact distribution of particles within such materials is probabilistic in nature, and, therefore quantities, such as the transmitted flux, become random variables. To reasonably evaluate the effectiveness of this type shielding, one must obtain the expected values and corresponding standard deviations of those quantities of interest.

In this dissertation, two models of a particle-loaded shield are investigated. The first is an artificial material postulated to consist of constant-thickness …

Wetting Of Carbon Filaments By Organic Liquids, Linden Tewes Halstead

Chemical and Biological Engineering ETDs

The object of this was to find the factors controlling the rate of wetting of carbon filaments by organic liquids. To carry out this study, the factors affecting the wetting of surfaces, such as the surface tension of liquids, and the contact angle formed at the liquid-vapor-solid boundary of a three phase system were discussed. At the same time, the anomalies with respect to contact angle, such as that relating to advancing and receding contact angles to dynamic angles was considered. As complimentary information, the methods used to obtain carbon and graphite filaments from cellulose and molten pyrolysis products were …

An Experimental Study Of Lateral Soil Pressures And Moments On Flexible Sheet Piles, James H. Donahue

Civil & Environmental Engineering Theses & Dissertations

In order to study the effect compaction has on lateral earth pressures exerted on and bending moments in steel sheet pile bulkheads, an experimental study was undertaken which employed the placement of a non-cohesive soil at two specific densities against three model piles of varying thicknesses. The soil was placed both in a loose and a dense state and the bending strains and deflections of the sheet piles were measured at various stages of backfill. Surface loadings were then placed after completion of the backfilling to observe the effects these loads had on the bending moments. The results of the …

Grain Size Reconnaissance Of The Virginia-North Carolina Inner Shelf Analysis By Settling Technique, Robert Bailey Sanford Jr.

OES Theses and Dissertations

The 2-fold purpose of this study is to calibrate a Rapid Sediment Analyzer and to use it to aid in the determination of the genesis of sediment on the inner continental shelf between Cape Henry and Cape Hatteras. Rapid Sediment Analyzer calibration was conducted by comparison of sieving and settling results of similar sands.

The study area was divided into sediment provinces by both a qualitative procedure (grain size and topography) and a quantitatively procedure (factor-vector analysis). Qualitative provinces are beach and surf, upper shore face, lower shore face, sea floor, and terminal shoals. The berm fines from each terminal …

Theoretical And Experimental Evaluation Of Cardiac State Utilizing Indicator Dilution Methods For Nonuniform Ventricular Mixing, Stanley Myron Welland

Dissertations

This research is directed toward the development and application of a new approach to the evaluation of cardiac work to diagnose cardiac state. A procedure has been developed for calculating the work performed on the fluid by the left ventricle during the heartbeat. The procedure involves the continuous direct measurement of ventricular fluid mixture temperature during and following the controlled injection, through a catheter, of a known volume of cold saline into the left ventricle. The measured mixture temperatures are used to calculate continuous ventricular volumes during the systolic and diastolic functions of the heartbeat. Plotting measured ventricular pressure versus …

A Kinetic Study Of The Anionic Polymerization Of Neopentylethylene Oxide, Albert Edward Meisinger

Dissertations

Kinetic data for the anionic polymerization of bulk neopentylethylene oxide were determined. The initiator used for this study was potassium t-butoxide. Polymerization runs were made at temperatures of 39.9, 60.0 and 80.3°C using monomer to initiator ratios of 50/1 and 20/1.

The polymerization reaction was found to follow pseudo first order kinetics up to about 60% polymerization and second order after this. The energy of activation for the propagation reaction was found to be 17.4 ± 1.2 K cal/mole and 18.5 ± 1.5 K cal/mole, respectively, for the pseudo first order and second order portions of the polymerization. The value …

On The Classification Of The Solution Space Of Linear Anisotropic Elasticity, Richard Clement Carman

Dissertations

A method is developed within the framework of Synge's function-space interpretation of problems in linear elasticity which allows the consideration of solutions to problems for anisotropic media in terms of the solutions of a corresponding isotropic problem and corresponding simpler anisotropic problems. The isotropic solution and simpler anisotropic solutions establish points in each of the statically and kinematically admissible spaces for the anisotropic problem. The established points are used to define sets of vectors in the statically and kinematically admissible spaces. The linear independence of these vectors can then be determined by a pair of criteria developed in this work. …

Continuous Esterification Of Lactic Acid With N-Butyl Alcohol, Robert Dix

Dissertations

A model is proposed for the reactions occurring when an aqueous 30% lactic acid solution is contacted with a primary alcohol, normal butanol. Kinetic and equilibrium data for the esterification reactions of monomeric lactic acid and dimeric lactic acid were determined in a series of experiments using an ideal overflow back-mix reactor. The variables studied were reaction temperature and catalyst concentration.

It was determined that the significant reactions occurring within this system are the esterification of monomeric lactic acid with n-butanol and the esterification of dimeric lactic acid with n-butanol. Other reactions that may be postulated to occur within the …

A Study Of The Dynamics Of Gas Adsorption In An Air Fluidized Bed, William Charles Zalewski

Dissertations

The dynamics of gas adsorption was studied in an air fluidized bed containing activated alumina particles. The adsorption studies made with a fixed bed and in the transition region between minimum fluidization velocity and 2.0 times minimum fluidization velocity, compliment work done at higher velocities. With adsorption, particle motion controlled the overall dynamics of the fluidized bed. A different approach in applying the two phase fluidization model was necessary to satisfactorily describe unsteady state adsorption in fluidized beds. Experimental and theoretical results were compared in frequency response plots to obtain a rigorous comparison. Good agreement was obtained for flow rates …

The Transferability Of Force Constants Among Olefins, John Martin Comerford

Theses

A normal coordinate analysis of the in-plane vibrations of ethylene was performed using a modified valence force field, a modified Urey-Bradley force field and a hybrid orbital force field. The B_2u species of isobutene was also analyzed. An attempt was made to transfer force constants from ethylene and thereby solve the A₁ species of isobutene, but a solution could not be obtained. This suggests that simple transference of force constants is not feasable in this case.

The potential energy distributions obtained for ethylene are discussed. The normal coordinates calculated in this work are appended.

The Absorption Of Hydrogen Chloride From Dilute Air Mixtures, Edgar L. Demarest

Theses

A study was made of the absorption of hydrogen chloride from air mixtures containing from 1 to 40 mgm. HCl/liter (1000 to 40000 mgm./m.³), using a.4" diameter tower packed with 2" Intalox saddles, irrigated with water or with sodium hydroxide solutions of 0.3% to 3.8% concen?tration. Gas flow rates of 177 to 752 lbs./(hr.)(ft.²) were investigated at three liquid rates: 2960 ; 4260, and 5700 lbs./(hr/)(ft.²). All data were collected below the flooding point.

Correlations of the height of a transfer unit with the superficial gas velocity were prepared for water and for sodium …

Aiir Pollution Emissions From Turbine Powered Aircraft, Raymond Arthur Filippini

Theses

The major pollutants that are emitted by jet aircraft include: particulate matter (soot), carbon monoxide, aldehydes, hydrocarbons, and nitrogen oxides. The first of the pollutants, particulate matter (smoke), constitutes not only a visual nuisance but is also a potential health problem. The rest, which are not visible, are irritants and in high enough concentrations can be toxic.

Since pollutants emitted by jet aircraft are of the same type as those given off by a car, a direct comparison is possible. In one landing take off cycle (LTO), a four engine jet aircraft emits the same amount of particulate matter as …

Phosphate Removal From Sewage Using A Combination Of Ferric Chloride And A Polymeric Flocculant, Ravindra C. Patel

Theses

The present work is concerned with a newer technique and approach to the problem of phosphate removal from waste water. This includes the removal of phosphate from the sample of activated sludge, i.e., a sample from the aeration tank of the secondary sewage treatment. The phosphate is removed by using ferric chloride as a precipitating agent and a cationic polyelectrolyte (P.E.) as a flocculating agent. Results of this study showed that: (a) P.E. addition gives a significant improvement in phosphate removal over that obtained by ferric chloride alone. In some cases the phosphate removal increased from 92 to 96.5 per …

Combined Feedforward-Feedback Control Of A Fluidized-Bed Reactor, Reginald Eugene Mitchell

Theses

Feedforward control, feedback control, and combined feedforward-feedback control were studied on an analog computer to evaluate their effectiveness in controlling a fluidized-bed reactor used for the decomposition of cumene. Proportional, proportional-integral, proportional-derivative, and proportional-integral-derivative modes of control were investigated. Step changes in set-point and load were used as disturbances. The Ziegler-Nichols method and the process reaction curve method of Cohen and Coon were compared in determining values of KC, Ti, and Td which gave optimum control of the fluidized-bed reactor.

Control equation were obtained from the block diagrams of the systems and solved on an EAI TR-20 Analog Computer.

It …

Viscoelastic Properties Of Polymer Melts, Wu-Shiong Lee

Theses

Thirteen samples of molten polymers were used to test Spriggs and Careau Models. Two empirical equations, one for apparent viscosity and the other which is new, for primary normal stress difference, were checked with these samples also.

In order to test the models, material functions were sought for some specific flow patterns under which the experimental data were collected, and then these functions were compared with data.

Careau Model was found to be better than Spriggs Model in representing molten polymer properties but still yield large deviations. Two empirical equations fitted data quite well and were expected to be useful …

Correlation And Prediction Of Diffussion Coefficients In Binary Gas Systems, Raymond Gerald Bailey

Theses

A correlation was developed for estimating binary gas diffusion coefficients by the reference substance method, in this case using the viscosity of air and subsequently its corresponding temperature. The derivation was made by the linear least square analysis of 65 different binary systems comprising 161 separate data points at temperatures ranging from 193°K. to 1200°K. At any given temperature only the critical molal volume and the molecular weights of the two gases of interest are required to calculate the diffusion coefficient. The correlation based on the viscosity of air had an average error of 7.67%. The correlation using temperature had …

The Relation Of Heat Transfer To Power Consumption Of Liquids In Turbulent Flow, John D. Bien

Theses

The relationship between the heat transfer ability and the power input requirement of liquid coolants in a turbulent heat transfer condition was investigated. A correlation in terms of the liquid physical properties and the required volumetric flow was proposed and the use of this correlation in selection of liquids as coolant was discussed. The optimum condition for a high heat transfer/power input ratio was also discussed.