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Iron Dynamics In A Gas-Water-Sediment Microcosm, Peter A. Cowan, V. Dean Adams, Donald B. Porcella Jan 1976

Iron Dynamics In A Gas-Water-Sediment Microcosm, Peter A. Cowan, V. Dean Adams, Donald B. Porcella

Reports

Iron dynamics in eutrophic systems were studied in the laboratory utilizing gas-water-Sediment phase sealed microcosms. Sediments from Hyrum Reservoir (2.4 percent iron by weight) were placed in the dark to simulate the hypolimnetic regions of a eutrophic impoundment. Iron both chemically and physically was readily available to microorganisms of the aqueous phase because iron in these systems was soluble. In the light microcosms, which simulated shallow littoral regions of eutrophic impoundments, iron was found in higher aqueous phase concentrations than was predicted chemically and physically; this was rationalized through biological mechanisms. The experiment was conducted in two phases: Phase I …


An Examination Of The Adaptive Random Search Technique, M. W. Heuckroth, J. L. Gaddy, L. D. Gaines Jan 1976

An Examination Of The Adaptive Random Search Technique, M. W. Heuckroth, J. L. Gaddy, L. D. Gaines

Chemical and Biochemical Engineering Faculty Research & Creative Works

Random search procedures have recently been successfully applied to the optimization of a variety of chemical engineering problems, including optimization of chemical processes by flow sheet simulation. These procedures represent the independent variables as random variables described by probability distributions. The adaptive random search procedure centers the distribution for each variable about the best search point found and examines this region for a better point. Thus, this technique has the ability of continuously moving the search region toward the optimum, which is particularly advantageous in following constraints. This study examines the efficiency of the adaptive random search technique as applied …


Mass Transfer To Drops Moving Through Power Law Fluids In The Intermediate Reynolds Number Region, Robert M. Wellek, Türker Gürkan Jan 1976

Mass Transfer To Drops Moving Through Power Law Fluids In The Intermediate Reynolds Number Region, Robert M. Wellek, Türker Gürkan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The mass transfer rate to fluid spheres is calculated for power law and Newtonian fluids by using the intermediate Reynolds number stream functions of Nakano and Tien (1970) and Yamaguchi et al. (1974), respectively. The Sh increases with increases in Re and Pe and decreases in n. Better results are obtained with Nakano and Tien's functions when Re > 10 and with Yamaguchi's functions when Re < 10. Copyright © 1976 American Institute of Chemical Engineers


Influence Of Turbidity On The Stratification Development Of A Deep Water Reservoir., David Allen Prouty Jan 1976

Influence Of Turbidity On The Stratification Development Of A Deep Water Reservoir., David Allen Prouty

Masters Theses

"The influence of turbidity on the diurnal temperature distribution and thermocline development in a deep water impoundment which is exposed to heating and cooling loads by convection, evaporation, and radiation is examined analytically. The diurnal behavior of the solar load, directional and spectral, is used with an isotropic multiple scattering model to simulate the attenuation of solar flux by turbid water. The diurnal behavior of the ambient temperature, humidity and wind speed were mathematically modeled to simulate the local (Phelps Co.) spring time of the year. The combined conduction and radiation energy transfer through the water was treated as a …


Electrical Degradation In High Purity Barium Titanate, Jeffrey Duncan Keck Jan 1976

Electrical Degradation In High Purity Barium Titanate, Jeffrey Duncan Keck

Doctoral Dissertations

"The stability of BaTiO3-type insulators to DC fields has long been recognized as one of the important factors in determining the quality of a capacitor which uses such a material as its dielectric. The slow increase of the electrical conductivity of an insulator which is stressed by DC fields at levels below the breakdown strength is normally termed degradation. Since degradation is a very common malady to the ceramic capacitor manufacturers, many studies have been conducted over the past two decades in efforts to learn how to remedy the problem.

The results of previous studies have shown that …


Threshold Characteristics Of Multimode Laser Oscillators, Lee W. Casperson Dec 1975

Threshold Characteristics Of Multimode Laser Oscillators, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

The oscillation characteristics of a multimode laser are considered in detail, and for the first time saturation by all of the cavity modes is included. Analytical expressions are obtained for the mode amplitudes, linewidths, and over‐all spectral characteristics of lasers operating above and below threshold. It is found that with increasing excitation the spontaneous emission spectrum is gradually resolved into a set of narrow discrete modes. Slightly above threshold the number of modes reduces in a homogeneoulsy broadened laser until only a single mode is oscillating strongly. The theoretical results are in agreement with experimental data that have been reported …


Application Of Cold-Formed Steel Sections To Primary Members Of Small Steel Buildings, Alejandro L. De La Barra Nov 1975

Application Of Cold-Formed Steel Sections To Primary Members Of Small Steel Buildings, Alejandro L. De La Barra

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.


Mode Properties Of Annular Gain Lasers, Lee W. Casperson, Mohammad Shabbir Shekhani Nov 1975

Mode Properties Of Annular Gain Lasers, Lee W. Casperson, Mohammad Shabbir Shekhani

Electrical and Computer Engineering Faculty Publications and Presentations

The properties of a new class of laser resonators are investigated theoretically and experimentally. In these lasers the radiation propagates longitudinally in an annular amplifying medium, and useful low loss modes can be obtained even when the axial region is obscured. Alignment characteristics and far field patterns are discussed, and experiments have been conducted using coaxial double-discharge CO₂ devices.


Planned Reduction In Electrical Energy Use In Nashville - Davidson County, Tennessee: A Preliminary Assessment, Barry D. Lichter, William F. Flanagan, Robert S. Goodrich, James K. Sebenius, C. Paul Beach Oct 1975

Planned Reduction In Electrical Energy Use In Nashville - Davidson County, Tennessee: A Preliminary Assessment, Barry D. Lichter, William F. Flanagan, Robert S. Goodrich, James K. Sebenius, C. Paul Beach

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

An assessment was carried out of the impacts of the various alternative strategies designed to reduce the rate of electrical energy use in the Nashville-Davidson County area, in the light of a potential crisis in supply. Seven strategies were identified among the major categories of voluntary reduction, price regulation, and mandatory reduction. Thirty-three sub-sectors were identified among residential, commercial and industrial users, and the consequences of imposing the strategies were assessed using a cross-impact matrix. The value of the methodology as an aid to public policy formulation lies in its possible extension to allow direct participation of various affected publics.


Industrial Innovations And Management Toward More Efficient Usage Of Electrical Energy, Tom Day Oct 1975

Industrial Innovations And Management Toward More Efficient Usage Of Electrical Energy, Tom Day

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

This paper deals with some of the industrial accomplishments in alleviating energy supply and demand problems. A survey is presented on how electrical energy in America is generated, resources used and kilowatt usage for the years 1970 to and including 1974. Conservation of electrical energy is the main theme in which three primary areas of innovation and utilization of industrial equipment are discussed; induction, lighting, heating and air conditioning. An awareness of natural gas shortages and the trend toward an "electric economy" are reviewed. The real challenge to energy management is apparent in order to handle the greatest expansion in …


Coal Conversion Technology, Karen A. Dollar, Henry Allen Wiebe Oct 1975

Coal Conversion Technology, Karen A. Dollar, Henry Allen Wiebe

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Energy consumption is rapidly increasing throughout the world and the United States is no exception. Efforts to reduce the dependence on oil imports have focused on utilization of our coal resources. This paper examines various coal conversion processes and presents a method for evaluating their contribution to energy production.


An Engineering Solution To Improve Water Quality In A Tidal Lagoon, Richard Warren Price Oct 1975

An Engineering Solution To Improve Water Quality In A Tidal Lagoon, Richard Warren Price

Civil & Environmental Engineering Theses & Dissertations

Rising demand for better water quality stimulated research and development of ways to improve the quality level in existing as well as proposed water systems. At present, most of the solutions focus on biological and chemical processes.

Many natural or man-made water bodies act as receivers for both point and non-point pollution sources. Employment of biological and chemical treatment has proved successful in many of these cases; however, in some cases a more natural physical solution of an engineering mode would be more desirable. A "flushing" technique using the tidal fluctuation as a driving force has been investigated and the …


Simultaneous Measurement Of Longitudinal Velocity And Temperature Fluctuations With A Single Wire In Non-Isothermal Flow, P. J. Mcconachie, K. J. Bullock Sep 1975

Simultaneous Measurement Of Longitudinal Velocity And Temperature Fluctuations With A Single Wire In Non-Isothermal Flow, P. J. Mcconachie, K. J. Bullock

Symposia on Turbulence in Liquids

A method for measuring longitudinal velocity and temperature fluctuations with a single wire probe is presented and the principles of operation verified by an analog computer solution of the finite hot wire, anemometer control and signal processor equations. Examination of the basic equations reveals that such a probe is best suited to the study of turbulent water flows, thus allowing high Reynolds numbers to be attained without limitations on frequency response. Inherent sources of error are investigated and the method shown to be reliant mainly on the initial accuracy of wire calibration.


Periodic And Random Excitation Of Streamlined Structures By Trailing Edge Flows, W. K. Blake Sep 1975

Periodic And Random Excitation Of Streamlined Structures By Trailing Edge Flows, W. K. Blake

Symposia on Turbulence in Liquids

This paper is an examination of semi-empirical techniques which are shown to be effective in predicting the response of hydrofoils to flow excitation. Examples are given for buffeting by inflow turbulence, excitation by the boundary-layer pressures on the hydrofoil, and linear and non-linear excitation by vortex street formation in the wake. Co-ordinated aerodynamic and hydrodynamic measurements are used in Reynolds number - scaled experiments to determine both the flow induced forces and the hydro-elastic behavior on cantilever struts. An analytical formulation based on normal mode theory is used to combine the results.


Local Mass Transfer In Turbulent Flow By Electrochemical Methods, C. Deslouis, I. Epelboin, B. Tribollet, L. Viet Sep 1975

Local Mass Transfer In Turbulent Flow By Electrochemical Methods, C. Deslouis, I. Epelboin, B. Tribollet, L. Viet

Symposia on Turbulence in Liquids

Mass transfer to the surface of rotating electrodes during turbulent flow was studied by electrochemical methods under steady and non-steady state diffusion conditions.

The flow was due to a large rotating disk made from insulating material, flush with the surface of which was mounted a ring shaped electrode of platinum or nickel.

A local study of the radial component of the convective diffusion in turbulent flow was carried out with very thin ring electrodes (width ΔR ~ 0,05 mm). The diffusion layer thickness was varied relatively to the diffusion sublayer thickness by changing the ring width or the rotation speed …


Some Observations Of Wake Behavior In Laminar And Turbulence Free Stream Flow, L. E. Seeley, R. L. Hummel, J. W. Smith Sep 1975

Some Observations Of Wake Behavior In Laminar And Turbulence Free Stream Flow, L. E. Seeley, R. L. Hummel, J. W. Smith

Symposia on Turbulence in Liquids

Visual observations of the sphere wake have been obtained using the flash photolysis technique. Free stream turbulence of 7 and 10% was found to progressively reduce the size of the wake but no turbulence was found in the attached shear layer nor was the position of the separation point affected. A separation bubble was identified as predicted by Son and Hanratty (1969). Evidence is presented to show that drag reduction in turbulent free streams is not due to turbulence in the attached boundary layer but to enhanced momentum transfer in the wake.


The Separation Angle For Spheres In A Pipeline, B. Latto, A. Lai Sep 1975

The Separation Angle For Spheres In A Pipeline, B. Latto, A. Lai

Symposia on Turbulence in Liquids

The results of a series of experiments on the measurement of the angle of separation for flow over steel spheres suspended in a vertical 5.18 cm ID pipeline with and without a drag reducing aqueous polymer solution are presented. Data were obtained for sphere- to-pipe diameter ratios of 0.74 and 0.925 with polymer concentrations of 0, 25, 50, and 100 wppm over a Reynolds number range of 1633 to 29400 for single spheres and trains of up to three spheres rigidly connected. It was found that relatively dilute polymer solutions can considerably affect the separation angle. Furthermore, that the angle …


Liquid Turbulence And Its Measurement, R. L. Humphrey Sep 1975

Liquid Turbulence And Its Measurement, R. L. Humphrey

Symposia on Turbulence in Liquids

This paper covers several principles which have been successfully developed over the past few years and used in the measurement of liquid flows. In particular, ultrasonics, electro-magnetics, thermal heat transfer and optical light transmission will be discussed. Each concept will be covered by basic definitions and laws, theory of operation and application where measurement parameters will be highlighted, thus allowing the user to choose the best instrument to fit his experimental needs.


Pollution Of Surface Irrigation Waters By Plant Pathogenic Organisms, James R. Steadman, C. R. Maier, H. F. Schwartz, E. D. Kerr Aug 1975

Pollution Of Surface Irrigation Waters By Plant Pathogenic Organisms, James R. Steadman, C. R. Maier, H. F. Schwartz, E. D. Kerr

Department of Plant Pathology: Faculty Publications

Systematic sampling of waterways and irrigation runoff from agricultural lands in the North Platte Project of Nebraska in July and August of 1972–1974 demonstrated that phytopathogenic organisms were disseminated. The organisms monitored included the bean common blight bacterium Xanthomonas phaseoli, the bean white mold fungus Whetzelinia sclerotiorum and various nematodes. Although many types of nematodes often were recovered from irrigation water, Heterodera sp. cysts which cause significant disease problems in the valley were found infrequently. Patterns of movement of the bacterial and fungal organisms were correlated with previous or current season infection of bean plants. The short-term survival of X. …


Combined Reflection And Transmission Thin-Film Ellipsometry: A Unified Linear Analysis, Rasheed M.A. Azzam, M. Elshazly-Zaghloul, N. M. Bashara Jul 1975

Combined Reflection And Transmission Thin-Film Ellipsometry: A Unified Linear Analysis, Rasheed M.A. Azzam, M. Elshazly-Zaghloul, N. M. Bashara

Electrical Engineering Faculty Publications

A scheme of combined reflection and transmission ellipsometry on light-transmitting ambient-film-substrate systems is proposed and the required sample design and instrument operation are investigated. A comparative study of the sensitivity of external and internal reflection and transmission ellipsometry is carried out based on unified linear approximations of the exact equations. These approximations are general in that an arbitrary initial film thickness is assumed. They are simple, because a complex sensitivity function is introduced whose real and imaginary projections determine the psi (Ψ) and delta (Δ) sensitivity factors. Among the conclusions of this paper are the following. (1) External reflection ellipsometry …


The Synthesis Of New Maleimide Addition Polymer Precursors, Richard B. Brown Jul 1975

The Synthesis Of New Maleimide Addition Polymer Precursors, Richard B. Brown

Chemistry & Biochemistry Theses & Dissertations

1H-2,3-dimethylpyrrolo(1,2-a) benzimidazol-l-one (27) and 1H,9H- 2,3,7,8-tetramethyl-bispyrrolo(1,2-a:6,7-a')benzodiimidazo1-1,9-dione (32) have been synthesized from dimethylmaleic anhydride and o-phenylenediamine and 1,2,4,5-tetraaminobenzene, respectively. The presence of reactive olefinic double bonds in the synthesized compounds was of interest as a site for possible addition polymerization.

The synthetic route involved, in both cases, a simple nucleophilic substitution reaction between the diamine(or tetraamine) and the anhydride to form an intermediate amide-acid-amine which rapidly cyclized to the imide amine. The final ring closure required more rigorous conditions and occurred at melt reaction temperatures.


The Thermodynamics Of Electrolytic Solutions, Eric Robert Bixon Jun 1975

The Thermodynamics Of Electrolytic Solutions, Eric Robert Bixon

Theses

The thermodynamic properties of solutions of electrolytes may be accurately determined by the measurement of the activity of the s6lvent. when the. solute is nonvolatile, this quantity may be obtained from measurements of the lowering of the vapor pressure caused by the presence of the dissolved solute.

An experimental method has been devised to measure this effect using a semi-conventional Othmer Still. The experimental apparatus has been constructed. and evaluated. Data has been-obtained for the vapor pressure lowering of methanol due to the presence of dissolved electrolyte for five different electrolyte-methanol systems. An extrapolation technique was developed to make use …


Steady State Heat Transfer From A Double Ring Of Identical Spheres In A Regular Orientation, Evelio A. Melo May 1975

Steady State Heat Transfer From A Double Ring Of Identical Spheres In A Regular Orientation, Evelio A. Melo

Theses

Solutions to Laplace's equation are obtained by the method of reflections for the problem of heat transfer from two parallel rings of spheres arranged in regular polygonal arrays. The mathematical models developed describe the rate of heat transfer and spatial temperature distribution due to an arbitrary number of identical spheres of equal surface temperature correcting Fourier's heat transfer equation for the interference caused by a multiparticle array. Although the method of solution is quite rigorous and can be used to obtain as accurate a solution as desired, only the second reflection was obtained, yielding a first order correction. The model …


Reactions Of Para-Nitroaniline With Acid Chlorides, Stephen Alan Zapoticzny May 1975

Reactions Of Para-Nitroaniline With Acid Chlorides, Stephen Alan Zapoticzny

Theses

Para-nitroaniline was reacted with acid chlorides forming amides. Their structures were elucidated by the performance of various spectral analyses.


Soluble Surfactant Effects On Gas Absorption Of Organic Compounds, Angelo C. Morresi May 1975

Soluble Surfactant Effects On Gas Absorption Of Organic Compounds, Angelo C. Morresi

Theses

A literature search dating back to the beginning of this century turned up no previous work similar to ours. We discuss several methods and experiments involving the scrubbing of air streams.

The objective of this work was the determination of surfactant affects on the solubility of certain organic compounds of varying solubility in water. A means of simulating a packed tower was devised to allow for bench scale evaluation and thus enabled a greater number of organic compounds to be examined with a greater variety of surfactants.

Curves were plotted based on organic vapor concentration, surfactant concentration, organic type, surfactant …


Gaussian Modes In High Loss Laser Resonators, Lee W. Casperson, Susan D. Lunnam May 1975

Gaussian Modes In High Loss Laser Resonators, Lee W. Casperson, Susan D. Lunnam

Electrical and Computer Engineering Faculty Publications and Presentations

Matrix techniques are applied to the mode analysis of laser resonators having spherical mirrors and Gaussian profiles of the mirror reflectivity. These same analytical methods provide a useful approximation to the mode and loss characteristics of conventional resonators having an abrupt discontinuity of the reflectivity. Mode selection in apertured waveguides and resonators is also discussed.


Electromagnetic Modes Of An Inhomogeneous Sphere, Lee W. Casperson Apr 1975

Electromagnetic Modes Of An Inhomogeneous Sphere, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Vector wave solutions are derived for the electromagnetic modes of a sphere having radial variations of the refractive index and gain. For some inhomogeneity models, confined-mode solutions exist. The results are applicable to the refracting atmospheres of stars and planets.


Computer Aided Structural Analysis: The Finite Element Method, Richard T. Ryner Apr 1975

Computer Aided Structural Analysis: The Finite Element Method, Richard T. Ryner

Graduate Research Papers

The design process is a complex and tedious one. Within it, the task of design verification appears to require the lion's share of time, effort, and money involved.

The design formulation activity requires creative people, placed in an environment where they are able to formulate ideas which eventually become the manufactured products of an organization. This task takes up comparatively little of the time and effort of the design cycle. Therefore, it would appear that the greatest savings could be made in the design analysis task. Further, if these savings can be made earlier in the design cycle, in the …


Ellipsometric Function Of A Film-Substrate System: Applications To The Design Of Reflection-Type Optical Devices And To Ellipsometry, R. M.A. Azzam, A.-R. M. Zaghloul, N. M. Bashara Mar 1975

Ellipsometric Function Of A Film-Substrate System: Applications To The Design Of Reflection-Type Optical Devices And To Ellipsometry, R. M.A. Azzam, A.-R. M. Zaghloul, N. M. Bashara

Electrical Engineering Faculty Publications

The ratio ρ = Rp/Rs of the complex amplitude-reflection coefficients Rp and Rs for light polarized parallel (p) and perpendicular (s) to the plane of incidence, reflected from an optically isotropic film-substrate system, is investigated as a function of the angle of incidence ϕ and the film thickness d. Both constant-angle-of-incidence contours (CAIC) and constant-thickness contours (CTC) of the ellipsometric function ρ(ϕ,d) in the complex ρ plane are examined. For transparent films, ρ(ϕ,d) is a periodic function of d with period Dϕ that is a function of ϕ. …


Data Acquisition And Management For Rock Evaluation, M. W. Palmer Feb 1975

Data Acquisition And Management For Rock Evaluation, M. W. Palmer

Kentucky Transportation Center Research Report

The primary goal of this thesis was the formulation of an integrated effort to collect, maintain, exchange, and evaluate engineering data on rock materials from a variety of information sources. The proposed rock evaluation program provides a data base of accumulated information by establishing procedures for characterizing rock, from specimen acquisition through indexing, classification and correlation studies of data, and the application of data for site selection, use tables, establishment of design parameters and alternatives, and maintenance of engineered facilities. The co-ordinated evaluation system detailed herein provides guidelines for implementation of an extensive system of data storage and retrieval to …