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Atomic Absorption As An Index Of The Silver Concentration In Precipitation, Silver Iodide Plume Studies, Part 1, Joel E. Fletcher, H C. Millar

Reports

The Perkin Elmbver Model 303, equipped with the DCR-1, digital concentration readout, was evaluated as to its ability to provide an index of silver concentration in water solutions, without concentrating in any manner. The procedures, principal settings, and adjustments which must be observed are described.

This instrument can detect the difference between concentrations of 10-15 and 10-12 gm/ml. However, as the concentration of silver decreases the experimental error increases to a point at which the error becomes greater than the differences in readout due to differences in silver concentration.

Water Quality Telemetry First Annual Progress Report, Duard S. Woffinden, Allen D. Kartchner

Reports

No abstract provided.

Feasibility Of Rating Current Meters In A Velocity Field, Gaylord V. Skogerboe, Lloyd H. Austin, Roland W. Jeppson, Chi-Yuan Wei

Reports

Preliminary studies employed an 8-inch (outlet diameter) contracting cone and an 8-inch converging nozzle. The design of the cone is based on an electromagnetic analogy reported by Smith and Wang, while the nozzle was designed assuming potential flow and using numerical methods to obtain the solution. Both designs yielded fairly uniform velocity fields, any deviations being primarily due to either construction or measurement techniques. The towing tank rating for a Pygmy current meter was compared with the submerged jet rating, the difference being 1 or 2 percent. A Prototype system was constructed using a 16-inch contracting cone (d). Two Type …

Solutions To Axisymmetric Seepage From Ponds Through Homogeneous And Nonhomogeneous Porous Media, Roland W. Jeppson

Reports

No abstract provided.

Hydraulic Characteristics Of A Modified Venturi Section, Muhammad Aslam Rasheed

Reports

The measurement of water in open channels on extremely flat grades is difficult because of the head loss that is necessary. A modified venture section, the contraction of which is provided by a top cover section mounted in a rectangular flume, is proposed to meet the requirements of a suitable measuring device for use in canals of flat gradients. The method of finite differences has been used for the mathematical solution to the idealized inviscid flow problem. This was followed by a laboratory investigation to ascertain the hydraulic characteristics of the proposed design. The experiments were conducted in a 3 …

Air Pollution Control And Abatement Proceedings Of A Symposium, Allen D. Kartchner

Reports

No abstract provided.

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 …

A Conceptual Model Of The San Pitch River Basin, James D. Ballif

Reports

To meet future expected needs for water, the State of Utah will have to plan and manage its limited resources in a judicious manner. Comprehensive water resources planning on a river basin basis is necessary to economically plan and develop the best combination of water uses. Efficient use and management of agricultural water is necessary to maximize the amount available for future needs. Irrigation water management must be improved. Improvements in the organization, storage, distribution, and method of application will be required to meet future demands. Consideration should be given to various combinations of conjunctive use of groundwater and surface …

A Numerical Simulation Of Pressure Distribution And Radius Of Drainage In Infinite Radial Aquifers - Constant Rate Case, Alton John Nute

Doctoral Dissertations

"The diffusivity equation for the transient flow of slightly-compressible liquids has been solved for infinite radial aquifers, subject to constant terminal rates, by employing a Romberg integration of the Van Everdingen - Hurst explicitly solution over the transformed integral limits for .01̲TD>500, the classical solutions presented by Carslaw and Jaeger, Mortada, Theis, and others are incorporated in the digital analysis to yield dimensionless pressures for 40 selected dimensionless radius (RD) ratios between 1 and 64 for dimensionless time values of .0005 to 1000.0. A new expression for dimensionless pressure-distribution, PD'(RD, TD), as a fraction of well bore pressure drop …

Recombination Statistics For The Neutron-Induced Base Current Component, Ming-Chwan Chow

Doctoral Dissertations

"This paper presents a derivation of the recombination statistical model for the neutron-induced base current component. The derivation was based on the assumptions: 1) the current equation for the induced current component developed by Goben is valid; 2) the Shockley-Read-Hall statistics for holes and electrons are applicable; and 3) the recombination statistics derived by Sah, Noyce and Shockley, for sites in the bulk space-charge region are valid. Several examples were presented to emphasize accuracy of this derived model for predictions. This paper shows that the recombination process may be described by a mathematical model, recombination statistics which depend on the …

Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe

Doctoral Dissertations

"Surface self-diffusion coefficients have been measured by a radioactive tracer method over the temperature range 614⁰ to 840⁰C on nickel (111) surfaces characterized by LEED. Previously unrecognized tracer evaporation during surface diffusion resulted in restricted spreading of the tracer at higher temperatures. A theoretical treatment of the tracer evaporation phenomenon is presented and subsequently used in the analysis of the data. The temperature dependence of the surface self-diffusion coefficient (D_s) for nickel (111) can be represented, over the experimental temperature range, by a single Arrhenius type relationship...Arguments are presented to justify an adatom surface diffusion mechanism which is …

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 …

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.

Permeability And Additive Sorption And Extraction In Lubricating Greases, Chan-Shan Fan

Masters Theses

"The effect of the area and type of surface of ten silica thickeners and aluminum oxide on grease permeability, on the sorption of PAN [Phenyl-α-naphthylamine] by the grease, and on subsequent extraction were studied. For grease containing 6% per cent of thickener, permeability coefficients varied from 20.1 x 10⁻¹¹ cm² to 168 x 10⁻¹¹ cm². For each silica type they decreased with increase in surface area of the thickener. The level of the permeability coefficient is generally related to the worked penetration. In sorption measurements using permeating oils of varying PAN concentration, the amount of PAN associated with the thickener …

Semiempirical Determination Of The Differential Fast Flux Spectrum For U-235 Fission With Water Moderator, Henry Anthony Till

Masters Theses

"The differential fast flux spectrum of the UMR Pool Research and Training Reactor core was determined by simultaneous activations of threshold foil detectors by neutron-nucleon reactions. This represents one phase of the composite neutron environment at two sample irradiation locations and the center of a fuel element during a power operation of 200 Kw (th). To accomplish this measurement a semiempirical least-squares approximation fitting activation date to a theoretical Cranberg U-wet fission spectrum was applied. This is a technique designed specifically for water moderated systems and takes into consideration both virgin and down-scatter neutrons. Gamma decay photopeaks were reduced using …

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

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 …

Evaluation Of Methods For Analysis Of Multi-Degree-Of-Freedom Systems With Damping, Brijgopal R. Mohta

Masters Theses

"A general review of various methods for studying the behavior of linear lumped parameter systems with viscous damping is presented. Five methods are discussed. These are: (1) Normal Mode Technique (2) Ho's Method (3) Impedance Method (4) Graphical Technique (5) A Method for Reducing Degrees-of-freedom. For solution of vibration problems by the Normal Mode Technique, the systems are classified as (1) classically damped or (2) non-classically damped. It is shown that the classically damped systems are relatively easy to solve. For non-classically damped systems, the method proposed by K. A. Foss has been employed. This method is quite complex, but …

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

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 …

Kinetics Of The Formation Of Strontium Zirconate, W. H. Parker

Masters Theses

"The decomposition rate of strontium carbonate (SrC0₃) was measured using a TGA apparatus. It was found to deviate slightly from zero order classical reaction. The rate of formation of strontium zirconate (SrZr0₃) from zirconium oxide (ZrO₂) and strontium oxide (SrO) in the form of the decomposition product of SrCO₃ was measured using quantitative x-ray diffraction for mineralogical analysis. It was found to most nearly follow the Zhuravlev-Lesokhin-Tempel' man rate equation. The rate of decomposition of strontium carbonate was found to be more rapid than the rate of formation of strontium zirconate such that for the most part strontium oxide is …

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 …

The Modeling, Fabrication, And Testing Of An Instantaneous Torque Measuring System, Thomas Phillip Hertel

Masters Theses

"The purpose of this work was to obtain a measuring system to experimentally determine the instantaneous magnitude and frequency of the torques from zero to 2400 Hertz produced by a single phase motor. This paper explains the methods employed in designing and fabricating a measuring system and shows the results from tests using this equipment. It was found that a measuring system based on the determination of the instantaneous value of the stator's reaction torques could be realized. Also, it was found that some simple methods of computation could be used to find the magnitudes of the frequency components comprising …

Determination Of Molecular Diffusivities In Liquids, Pai-Chuan Wu

Masters Theses

"A porous plate, initially at a uniform solute concentration is immersed in a well-stirred pure solvent bath of known volume. It is desired to find the molecular diffusivity of the solute-solvent system by observing the change of the solute concentration in the solvent bath with time. In this study, concentration-time data were curve-fitted by non-linear, least squares techniques to the various mathematical solutions describing molecular diffusion in the porous frit. This technique is used to determine the diffusion coefficient and predict the value of other parameters existing in the different mathematical diffusion models. The results from the different models are …

Signal Theoretic Characterization Of A Function Using Positive Exponential Basis Functions, James Julius Baremore

Doctoral Dissertations

"A signal theory characterization of a time function or signal is a representation of the function throughout a sample interval by an orthogonal basis function expansion. The characterization described here obtains the coefficients in the expansion by processing the input waveform, in real time, through a system of three terminal passive RC filters. The outputs of the filters are sampled periodically and the coefficients of the basis function expansion in that interval are related to these values. The basis functions result from an exponential transformation applied to the Legendre polynomials and are orthogonal in time over the sample interval. The …

Analysis Of A Focus Log Electrode In A Non Homogeneous Medium, John Julian Zenor

Doctoral Dissertations

"The mathematical model presented for the focused logging system is applicable to any resistance logging tool of the electrode type. Horizontal or cylindrical resistance interfaces may be included in any combinations. The tool and its environment are compartmentalized, and the integral form of the condition for continuity of current is applied to each compartment. Acceleration methods are applied to the iterative solution of the resulting large-scale system of linear equations. Two specific models are presented, one for the study of the effects of invasion and the other for the study of the effects of bed thickness on the apparent resistivity …

Hrva - A Velocity Analysis Technique For Seismic Data, John Charles Robinson

Doctoral Dissertations

"A High-Resolution Velocity Analysis (HRVA) has been developed for the determination of the root-mean-square subsurface-velocity energy spectrum from gated seismic data which has been normal-moveout corrected. All calculations are performed in the frequency-space or frequency-wavenumber domain; seismic gates are transformed from the time-space domain via the Fast Fourier Transform algorithm. HRVA is not restricted to the investigation of apparent horizontal velocities which have associated stepout values that are integral multiples of the time sampling interval, as are the existing correlation techniques. The technique liberally exploits the inexistence of significant energy in the higher frequency harmonies of seismic data, resulting in …

Training Needs For Metal Tradesmen In Iowa, Harlan E. Giese

Dissertations and Theses @ UNI

This study was undertaken to assist area schools and the State Board of Public Instruction by identifying the industrial training needs for semi-skilled and skilled metal tradesmen.

One of the problems confronting the administrators of the area community colleges, vocational schools, and high schools in Iowa is that of identifying the industrial training needs of manufacturers and business firms in the state. This need identification is necessary so that students trained in occupational curricula in the area-community colleges and vocational schools, and local high schools will find jobs available in their field of specialization when they graduate.

The area schools …

Recombination Statistics For Neutron Bombarded Silicon Transistors, M. C. Chow, J. L. Azarewiczt, C. A. Goben

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a recombination statistical model for the neutron-induced base current component reported previously. The derivation was based on the following: 1) the current equation for the induced current component developed previously; 2) the Shockley-Read-Hall statistics for holes and electrons; and 3) the recombination statistics derived by Sah, Noyce and Shockley for sites in the bulk space-charge region. The recombination statistics model depends on the diffusion potential, the junction voltage, the activation energy, temperature, and the ratio of capture cross-sections for holes and electrons. The utility of such a recombination statistical model is illustrated by using measured parameters to …

Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe

Doctoral Dissertations

"The circulating drop mass transport model based on Hadamard's dispersed phase stream function was solved numerically to account for a solute diffusing into a droplet and undergoing a first order irreversible reaction with the drop medium for the case where the continuous phase resistance to solute transport is negligible ... Experimental data were obtained for a system which consisted of 2-chloro-2-methylpropane (t-butyl chloride) diffusing from a benzene continuous phase into falling water droplets and undergoing a first order irreversible reaction with the water droplets ... The experimental solute transport rates were a factor of 7 to 10 greater than those …