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A New Determination Of The Homogeneous Nucleation Rate Of Water In Helium, Edward Francis Allard

Doctoral Dissertations

"The object of this investigation is to apply the best known cloud chamber techniques to the study of condensation phenomena, directed mainly toward the development of a precise method for the determination of homogeneous nucleation rates. A secondary object is to investigate the properties of re-evaporation nuclei so that adequate precautions may be taken to eliminate their detrimental effect in the homogeneous nucleation experiments"--Statement of Problem, page 10.

A Study Of Plane And Spherical Compressional Waves In A Voigt Viscoelastic Medium, Gerald B. Rupert

Doctoral Dissertations

"In investigating the behavior of waves traveling through cohesive solids, two assumptions are usually made: that the propagating medium is either elastic or viscoelastic, and that the wave is either planar or spherical in form. For small distances from the source of the disturbance the medium can be considered elastic and the wave spherical rather than planar. The assumption of elasticity allows considerable simplification of the mathematical analysis, and assuming a spherical wave form is an acceptable approximation if the initial disturbance is essentially a point source and the propagating medium is nearly homogeneous. However, for large distances from the …

On The Kirkwood Superposition Approximation, Russell V. Cochran Jr.

Doctoral Dissertations

"When the Kirkwood superposition approximation for the triplet distribution function is used in the Born-Green equation for the pair distribution function of a liquid, the fourth virial coefficient is given incorrectly. In view of this, two suggestions for improving the approximation have been investigated. A suggestion, due to G.H.A. Cole, that better results could be obtained by using a second-order integro-differential equation of the Born-Green type with the superposition approximation used for both the triplet and quadruplet distribution functions has been investigated, and results for a hard-sphere model show that this method gives considerably less reliable results than those obtained …

A Thermodynamic Study Of The Zirconium-Sulfur, Titanium-Sulfur And Hafnium-Sulfur Systems In The Disulfide-Trisulfide Region, Norbert Achilles Vermaut

Doctoral Dissertations

"A static method was used to study the equilibria which exist between the higher sulfides of zirconium and sulfur at temperatures from 700° to 1000 °C. Both disulfide and trisulfide have been identified by chemical analysis and X-ray diffraction. There exists a two-phase region of 'ZrS₂' and 'ZrS₃'. The composition limit of the homogeneous disulfide phase appears to exist between ZrS_1.90 and ZrS_2.00. The lower composition limit of the homogeneous region of the trisulfide phase was established as ZrS_2.75.

An experimental method of Blitz and co-workers, i.e., the use of evacuated …

A Study Of Soviet Music Education, Norman Alan Haltmeyer

Dissertations and Theses @ UNI

The great emphasis that the people and government of the Union of Soviet Socialist Republics place upon the study of music, and the encouragement that they give to musical participation on the amateur and professional levels make an investigation of Soviet music education most appropriate . This study has been made with the hope of achieving a new and better understanding of the Soviet method of educating the people and, more specifically, education as related to music . This age of tremendous unique educational advance brings the responsibility of improved instruction to every society. The future of the United States …

Using Sordaria Fimicola For Teaching Genetic Segregation, Crossing Over, And Probability, Roger Green Isaacson

Dissertations and Theses @ UNI

Since the late 1950's, American education has been undergoing a critical evaluation and review. This review has brought about some changes in emphasis and an upgrading in science curricula. The American Institute of Biological Sciences, supported by the National Science Foundation, accepted major responsibility for the field of biology and established the Biological Science Curriculum Study (BSCS). H. Bentley Glass., Chairman of BSCS, states: "The aim of the Biological Science Curriculum Study is to place biological knowledge in its fullest modem perspective. To accomplish this aim, a program of research, writing, testing, and evaluation was inaugurated.

Smith Wildman Brookhart: Iowa's Last Populist, Ray S. Johnston

Dissertations and Theses @ UNI

Since the age of Andrew Jackson, American political aspirants have recognized a value in being identified as a candidate of and from "the people." Frequently a good deal of effort and money is expended to convince the electorate that prospective officeholders are "self-made" men of humble origins. In this respect Smith Wildman Brookhart's early life might well epitomize the dream of a political public relations man, for he was truly of humble origins and was indeed a man who had overcome great odds. Smith Brookhart was born in a log cabin just across lowa's southern border in Scotland County, Missouri, …

A Study Of The Public Relations Program Of The Valley Park School, Cedar Falls, Iowa, Puran L. Rajpal

Dissertations and Theses @ UNI

Public relations is a relatively new field in educational administration and it has possibilities for further study that have scarcely been explored. "It is new in the sense that the importance of this field was not formally recognized until a few years ago when provisions were made for it in the management of educational institutions. In recent years educational leaders have been increasingly aware of the importance of effective school public relationships. James L. Hymes, Jr., said, "Home-school relations is a new field. Very little research and experimentation are available as direct guides.”

It was the purpose of this study …

Compressive Strength Of Stone Aggregate Concrete Using A North Dakota Lignite, Fly Ash Additive, Antony Vairamides

Theses and Dissertations

No abstract provided.

Factors That Influence The Selection Of Business Teaching As A Career Among Students From Selected Colleges In The United States, Patricia Watson Thornton

Theses and Dissertations

No abstract provided.

Current Practices Regarding The Use Of Blank Or Open Typewriter Keyboards For Typewriting Instruction, Laverne D. Thoreson

Theses and Dissertations

No abstract provided.

The Textile And Clothing Practices Of Families Of North Dakota, Shirley A. Sanderson

Theses and Dissertations

No abstract provided.

The Temperature Dependence Of The Magnetoresistance Of Thin Ferromagnetic Films, Ronald J. Shimek

Theses and Dissertations

No abstract provided.

A Comparative Study Of Non-College Bound Graduates From Selected Guidance And Non-Guidance High Schools, Dewayne J. Kurpius

Theses and Dissertations

No abstract provided.

A Comparison Of The Effects Of Seasonal Participation In Selected Interscholastic Sports On Physical Fitness, Clifford J. Moser

Theses and Dissertations

No abstract provided.

Distribution Of Sodium Perchlorate Between Tributyl Phosphate And Water, John A. Tengler

Masters Theses

"The questions posed by Carroll (23) concerning a TBP-H₂O system and an alkali salt -which is appreciably soluble in TBP have been partially answered by the experiments described in this thesis"--Conclusions, page 38.

The Anodic Dissolution Of Zinc In Nitrate Solution., Jo Lisle Reed

Masters Theses

"The increasing demand for protective metals as coatings and non-corrosive alloys has stimulated extensive research on the fundamental behavior of metals in corrosive media.

One of the problems still unsolved is the nature of the mechanism of the anodic dissolution of metals like zinc, magnesium, beryllium, cadmium, and aluminum in aqueous salt solutions. Several schools of investigators have proposed different and opposing theories to explain the discrepancies which often arise between coulometric data and the weight loss of metal electrodes in certain salt solutions.

The purpose of this investigation was to obtain experimental data for the anodic dissolution of zinc …

Study Of The Temperature Dependence Of The Haeffner Effect In Mercury, Charles George Arnold

Masters Theses

“In 1953, E. Haeffner (1) reported that after he had passed a direct electric current through a capillary tube filled with mercury, he obtained a separation of the isotopes of mercury. It was found that the heavier isotopes were enriched at the negative terminal and the lighter Isotopes at the positive terminal. This effect has since been referred to as the Haeffner Effect. Since this original experiment, other investigators have observed this effect in many other liquid and some solid metal systems.

The work of J. N. Baysden (2) showed that the separation of the isotopes in mercury could be …

Correlation Of Chemical Structure And Distensibility Of Polyesters., Nitin Jhaverbhai Bhimani

Masters Theses

"Maleic anhydride and fumaric acid are important raw materials for the manufacture of unsaturated polyesters. Unsaturated polyesters are the esterification products of unsaturated dibasic acids and polyvalent alcohols, polymerized to a high molecular weight resin"--Introduction, p. 1

Correlation Between Drying Times Of A Vinyl Copolymer Solution And Properties Of Dried Films., Abd El-Rahman M. Naser

Masters Theses

"One of the common methods used in film formation is the solvent evaporation method. As the evaporation starts the viscosity increases due to the inability of the solvent to keep the chains apart, which leads to a drag between molecules.

The rate of evaporation of the solvent (loss of solvent) cannot be equated with the rate of drying, since the latter depends on the results of the loss of solvents in terms of viscosity and plastic properties. The drying time can be defined as the rate at which a film increases its viscosity and thus changes the properties of a …

The Prediction Of The Viscosity Of Multi-Component Non-Polar Gaseous Mixtures At Atmospheric Pressure., Gary D. Fehsenfeld

Masters Theses

"The applicability of the Strunk, Custead, and Stevenson method for predicting the viscosities of multicomponent, non-polar, gaseous mixtures vas investigated. The viscosities of 24 ternary and quaternary gaseous mixtures were experimentally determined, at 3 temperature levels, and compared with the corresponding calculated viscosities resulting from the prediction method. In addition, the published viscosities of 64 multicomponent mixtures were compared with the corresponding calculated viscosities.

Altogether, the viscosities of 136 multicomponent, non-polar, gaseous mixtures were compared. The mixtures contained from 3 to 7 components including 16 different gases in the temperature range from 5• to 1014 ° c, and at a …

A Rubber Membrane Analogy For The Study Of Shafts In Torsion., Myron D. Bruns

Masters Theses

"The thesis presents a review of literature giving reference to several books which present the many and varied methods of determining the shearing stresses in shafts. However, no reference was found that used a rubber membrane analogy similar to that used in th is thesis. The theory of torsion, the membrane theory, and its analogy have been presented for a better understanding of the subject. Illustrations are used freely for clarity.

Analytical methods and solutions are given for two problems. The first method is that of writing a Saint-Venant stress function and satisfying the necessary conditions for it to be …

Use Of Sr-4 Strain Gages Under Hydraulic Pressure, Manubhai M. Patel

Masters Theses

"In this investigation an attempt has been made to determine the effects of hydraulic pressure on SR-4, type A-5 strain gages. A thick-walled aluminum alloy cylinder without end constraint was used to make an experimental study of the effects of hydraulic pressure on these strain gages.

The behavior of this cylinder under different internal hydraulic pressures was also studied by measuring the strains by means of strain gages which were attached to the inside and outside surface of the cylinder. The problem has been studied by applying pressures up to 4800 psi.

Because of the high internal fluid pressures various …

The Design, Construction, And Operation Of A Conducting Field Analog Computer., Richard T. Johnson

Masters Theses

"The purpose of this investigation is to design and construct a simple conducting field analog to solve problems described by the two-dimensional Poisson or Laplace equations. Decisions concerning choice of conducting media, construction of problem models, and design and construction of a specialized power supply with instrumentation were based on the results of previous experiments. Several problems are solved using the designed apparatus. Partial solutions to these problems are displayed in graphical form.

The greatest deviation of the experimental results from iterative values was consistently less than 8%. In most cases the deviation was less than 6%. The console arrangement …

A Study Of Rotational Critical Speeds For A Multi-Mass System By Influence Coefficients, Kantikumar G. Patel

Masters Theses

"In this investigation an attempt has been made to determine the critical speeds of a multi-mass rotational system by using influence coefficients. Modes of vibrations are also examined at these critical speeds.

A shaft carrying five masses, supported by bearings at the ends, has been studied analytically. The length of the bearings is considered small with respect to the shaft length and therefore, the configuration is assumed to be point supported as a simple beam. The five masses, each weighing one pound, were placed at equal distances of 10 inches on a 60 inch shaft. The critical speed was examined …

The Effect Of Metallic And Inert Electrodes On The Electrochemical Degradation Of Alkyl Benzene Sulfonate., Thomas Patrick O'Farrell

Masters Theses

"The purpose of this study was to investigate the effects of various metallic and inert electrode combinations on the electrochemical degradation of alkyl benzene sulfonates (ABS) in water and to determine the rate and degree of AB3 removal.

Selected combinations of copper, aluminum, iron, and carbon plate electrodes were studied in systems of tap, distilled and river waters containing an initial ABS concentration of 10 mg/1, using a current density of approximately 0.5 milliamperes per square centimeter and a total detention time of 6 hours. Samples were collected at appropriate time intervals and were analyzed for ABS, chemical oxygen demand …

Minimum Frictional Characteristics Of Optimum Journal Bearings., Navinchandra F. Shah

Masters Theses

"This investigation was conducted to develop a graphical representation to determine the optimum bearing conditions for minimum friction and to establish a theoretical approach for journal bearing design.

A series of graphs has been plotted for· the coefficient of friction versus the eccentricity ratio based on the. Sommerfeld number derived from Reynolds' differential equation, f or optimum journal bearings.

The results obtained in this research have been compared with those developed by other investigators. This comparison confirms the validity of the results presented in this thesis, so that it could be used advantageously for the design of optimum journal bearings"-- …

Stability Investigation Of Pipe-Line Suspension Bridges, Ten-Hsi Chen

Masters Theses

“This thesis presents an analysis of the behavior of pipe line suspension bridges under the action of wind. From this analysis a differential equation of vertical vibration is derived and solved, and the possible methods of preventing its vibration are discussed and suggested”--Abstract, page ii.

A Survey Of On-Campus Freshman Women Students Who Withdrew From The State College Of Iowa, 1959-1961, Joan E. Meyer Duea

Dissertations and Theses @ UNI

The major purposes of this study were to evaluate information pertaining to the freshman women who resided in on-campus housing facilities at the State College of Iowa during the 1959-60 and the 1960-61 academic years and withdrew during the first year or at the end of one year of college; and to suggest implications which might be considered by college officials in the examination of college personnel services.

An Investigation Of The Origin And Nature Of Contraction Fissures In The Vicinity Of Grand Forks, North Dakota, John N. Waxvik

Undergraduate Theses and Senior Projects

Cracks appearing in vegetation-free areas and on level surfaces in the vicinity of Grand Forks, North Dakota were investigated during the winter and spring months of 1964. The width of these cracks was measured to determine if there was any significant change in their size that would correspond to a change in temperature.

It was determined that there is a linear relationship between the temperature and the width of the cracks, and if recording and observing errors could be eliminated, the values would have much more significance in subsequent investigations.

After an extensive review of the literature, several possible means …