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The Effect Of Spontaneous Crystallization Of Some Inorganic Compounds At The Critical Temperature Of Their Solvents, John William Buttrey

Masters Theses

"For many years the phenomena which occur at the critical temperature of liquids have been investigated. And since 1912, when Laue and other discovered that a beam of x-rays could be made to yield a diffraction pattern by passing it through a crystal, scientists have been attempting to change the x-ray pattern for various crystals by somehow changing the arrangement of the atoms in the crystal lattice. Harvalik has already shown that crystallization occurs when a solvent reaches the critical point and his work indicates that under these conditions of crystallization there is a change in the crystal pattern. The …

Hysteresis Loss Of Supermalloy At Different Temperatures, Chester Ray Holland

Masters Theses

"The object of this investigation was to measure the hysteresis loss of supermalloy at different temperatures, and to see if temperature had any effect on hysteresis loss and permeability. The maximum magnetizing current was held constant for all temperatures"--Introduction, page 1.

The Kerr Electro-Optic Effect In Plastic Materials Transmitting Infra-Red Radiation, James Edson Dueker

Masters Theses

"Much work has been done investigating the Kerr Electro-Optic effect and what physical properties of a substance lead to the occurrence of the phenomenon. Information now available indicates a relationship between molecular shape and orientation with the Kerr Effect, hence any added information increases the possibility for finding the exact relationship and the molecular structure of substances. The Kerr Effect, has been used in a number of applications other than for the study of molecular construction of matter. Many applications have been made to form Electro-Optic shutters. This field of work has been increased to include light flash production and …

Radioactivity Of The Pre-Cambrian Section Of The Bourbon, Missouri, Well Core By Measurement Of The Total Hard Gamma Radiation, Paul E. Damon

Masters Theses

"In December of 1947 Mr. Robert Van Nostrand and the writer became interested in the problem of the distribution of natural radioactivity and the applications of radioactivity to geology. A cooperative survey of the literature on the subject was undertaken. Later the writer decided to follow up the survey with a research project. Consultations with Dr. Z. V. Harvalik of the Missouri School of Mines Physics Department, and Dr. E. L. Clark and Mr. O. M. Bishop of the Missouri Geological Survey, followed. The nature of the project was evolved when Dr. Clark, with the consent of the U. S. …

A Microwave Polarimeter, Alfred E. Schwaneke

Masters Theses

"The dissertation on the following pages may read more like a construction article than an approach to a study of physical phenomena. If so, its purpose is clearly defined. this subject has been studied little from an experimental viewpoint, so one of the main objectives of this writing is to describe the instrument so others may read the article and reproduce this or an equivalent device without a great amount of reading and searching for information on just how to fabricate and mount the parts. No single book or article that I know of covers the inexpensive construction of such …

A Device For Determining The Electrical Characteristics Of Common Industrial Electronic Tubes, Addison Dabney Campbell

Master's Theses

Many tube checkers designed for radio receiving tubes have been developed . Most of the devices for test­ ing these tubes do little more than check the emission of the cathode. This is usually accomplished by applying alternating voltage to the plate of the tube undergoing the test and reading the direct-current component of the plate current . In this case, the control grid bias volt­ age is usually set at a fixed value although sometimes facilities for varying the bias are provided. If the tube is of the multi-grid type, all the grids except the control grid are connected …

The Construction And Use Of The Barrett Camera, Theresa Pauline Radermacher

Bachelors’ Theses

The study of the crystal structure of metals under various conditions of strain is at the present time the object of a great deal of scientific endeavor. A greater knowledge of the condition of strained crystals will be a tremendous aid in the future development of metallic construction for one can then predict the effect of any type of strain on a metal by the reaction of the individual crystals to that particular strain. It is the purpose of this paper to describe the construction and use of the Barrett camera which is used in experiments of this kind.

Spectroscopy, Harvey E. Wagner

Bachelors’ Theses

This thesis was first concerned with a spectroscope based on an eagle mounting (instrument no. 57034). However, due to apparatus difficulties it was necessary to start again using a spectroscope based on a Paschen Runge Mounting (instrument no. 37102 - 124 Central Scientific Co.).

Thermal Conductivity Of Air Layers, Zaboj V. Harvalik

Journal of the Minnesota Academy of Science

No abstract provided.

The Interplaner Spacings Of Atoms In Titanates, Elizabeth R. Mcgrath

Bachelors’ Theses

The science of crystallography was founded about one hundred fifty years ago by Rene Hauy. This science is the study of the outward form of crystals, and soon the crystallographer learned to classify the crystalline substances according to their outward form, particularly by the angles formed between faces of the crystals.

Corona Discharge From Antenna Wire: A First Partial Report, Robert Katz

Robert Katz Publications

Purpose: 1. To examine the conditions for corona at the surface of a wire. This report is a theoretical discussion. No test procedure was used.

Conclusions:
1. Calculation of the gradient at the surface of the fixed-wire liaison antenna (bare copperweld, .040" diameter) on the B-17 airplane indicates that it is of the order of 200 times the gradient measured at the top generating voltmeter.
2. Further work will be done by the Special Devices Branch in an attempt to determine the conditions under which insulated wire goes into corona.

X-Ray Inspection Of Castings (Army Air Forces' Requirements), Robert Katz

Robert Katz Publications

The author contributed a brief account of the radiographic practices necessary to comply with government specifications to a round table discussion on inspection methods at the last American Society for Metals Convention, and later was able to release for publication in Metal Progress a full set of the radiographic standards set up about a year ago to govern acceptance of structural castings for airplanes. Representaive negatives are reproduced in this article. Those eliminated are either of similar defects which did not register strong enough to appear on an engraving without retouching, or of defects readily observed by visual inspection without …

A Generating Voltmeter Of Wide Sensitivity Range For Measuring Atmospheric Potential Gradients, Herschel Roy Snodgrass

Physics & Astronomy ETDs

The specific need for the present instrument arose out of a consideration of the significant results that might be obtained through a coordination of reliable data on potential gradients under various cloud formations with the accompanying fast motion cloud photographs. The characteristics most desired were: (1) the continuous measurement of both the magnitude and polarity of the surface potential gradients over a wide range of values, from normal fair weather gradients of 0 to +300 volts per meter to thunderstorm gradients, possibly as high as 200,000 volts per meter; (2) easy portability; (3) resistance to harmful effects from rain, dust, …

Threshold Values For The Perception Of The Direction Of Frequency Modulation, Abe Pepinsky

Journal of the Minnesota Academy of Science

No abstract provided.

Characteristics Of Spectrographic Plates In The Ultra Violet Region Between 2300-2000a, R. G. Beck, L. Lundberg, Elmer S. Miller

Journal of the Minnesota Academy of Science

No abstract provided.

The Relative Influence Of Raw Material Components Upon The Thermal Expansion Of Vitreous Enamel., Robert C. Boyd

Electronic Theses and Dissertations

No abstract provided.

A Study Of The Effect Of An Equal Energy Spectrum Upon Metallic Selenium In Vacuo, George Butler Scott

Master's Theses or Doctor of Nursing Practice

Since little has been found in the literature, on the effect of a actinic properties on the conductivity of metallic selenium and on its spectral response when possessing these properties, it was thought noteworthy to construct several selenium cells having low and medium dark resistances and to study them with a view of seeking some correlation between their conductivity characteristics and their prismatic response in vacuo.

The Propagation Of Ten Meter Radio Waves By Vertical And By Horizontal Dipole Antennas, James William Haddock

Master's Theses or Doctor of Nursing Practice

Radio communication is made possible by means of energy that travels through space from the transmitter to the receiver in the form of electromagnetic waves. These waves move with the velocity of light and differ from visible light only in wave length or frequency. This radiant energy consists of a magnetic field and of an electrostatic field, at right angles to each other and also at right angles to the direction of propagation. Questions explored in this thesis include: 1. Is there a relation between the amount of reflected radio energy and the angle of polarization. 2. If so, which …

The Tesla Coil, Willard H. Schultz

Bachelors’ Theses

The following paper is an attempt to gather together and present in some order a few of the facts concerning the design, theory, and operation of the Tesla Coil. The writer's interest was first directed to the production of high frequency, high potential current by an article appearing on page 594 of the October, 1933 issue of the Popular Mechanics Magazine. Here the construction of a small coil was described. The writer built such a coil and was greatly disappointed with the results obtained from it. As is so frequently the case, this failure only intensified the desire to construct …

The Photography And Identification Of The Secondary Spectrum Of Helium, Elizabeth Moy Toy

Bachelors’ Theses

Spectra are generally classified as emission or absorption spectra. Whenever a source is radiating, it is producing an emission spectrum. If the source is solid, such as the filament of f lamp, the spectrum is generally continuous, that is there is no interruption on the contlnum of wavelengths. When the source of radiation is a gas at normal or low pressures, it consists of bright isolated lines on an otherwise dark background, that is, it is discontinuous. Such spectra may be observed in flames, when metallic salts are introduced; in spaces between the electrodes of electric arcs; in spark discharges; …

A Study Of Melting Points Of Various Binary And Tertiary Mixtures Of Waxes, Neil G. Goodrich

Bachelors’ Theses

The work undertaken in this thesis was done in cooperation with Joseph Sevenich and is a continuation of the work done by George Hable, Leonard Veranth and Lewis Wrangell. In this present work, the melting points of various trinary mixtures of waxes was studied, also the reliability of the method used in the determinations, and the effect of heat upon the mixtures. Graphs are used in the thesis in order to present a clearer picture of the work done and the results obtained.

Radioactive Properties Of The Subterranean Waters Of Ellis County, Kansas., Verne Lippert

Master's Theses or Doctor of Nursing Practice

Soon after the discovery of Becquerel rays in 1896, tests were made on ordinary matter to see if all matter were radioactive. Although there is evidence to show that all matter is radioactive, to a degree and under certain conditions, it has been found that the greater part of the observable effect is due to traces of radioactive material permeating all matter in general. Thus, radium and its products being the most active of radioactive substances, the surface of the earth is covered with traces of these radioactive substances but the amount varies from place to place. Moreover, determinations of …

Educative Value And Construction Of Laboratory Equipment For Physics, With Emphasis On An Optical Screen, Warren D. Conrad

Bachelors’ Theses

In the preparation of this thesis the writer has constantly kept in mind three distinct purposes: a) to show the place and importance of the lecture-demonstration in the teaching of physics; b) to provide the teacher of physics in the small high school a means whereby he may equip a laboratory at the smallest possible cost; and c) to describe in detail the construction of an optical screen for purposes of demonstration, indicating what can be done. in the building of home-made physics apparatus.

The Value Of High School Physics To The College Student, Emery White

Masters Theses & Specialist Projects

Secondary school science consists of biology, chemistry, physics, or a combination course known as general science. General science deals only with the practical side of the laws of physics. It fails to go into detail and very often omits the law entirely. Physics in high school requires a special room in the building which is not easily adapted to other use. A large amount of expensive equipment is need to teach it efficiently. Can all of this expense be justified? Is the student who ends his school career with high school graduation sent out into life with a large amount …

A Configurational Approach To Sound, Alfred R. Root

Journal of the Minnesota Academy of Science

No abstract provided.

A Short Study Of Laplace's Equation, Sidney Teweles Jr.

Bachelors’ Theses

Perhaps if I set forth my original inspiration for this thesis, the reader will be better able to understand the reason for the apparent limitations of treatment. In my study of differential equations, I had the task set before me of presenting a discussion of Laplace's equation to the class. A seemingly easy matter turned out to be quite difficult for the reason that most texts make but brief use of Laplace's equation. Thus in a mathematics book reference will be made to Laplace's equation simply as example of a mathematical process. Some of these processes are the change of …

The Application Of Differential Equations To The Laws Of Physics, Sherman Baker

Bachelors’ Theses

In this treatment of the mathematical expression of physical laws, all proofs and expositions of problems that are taken from particular books are acknowledged in the text. Formulas and proofs that are given in a conventional form by authors generally and are the property of no single man are not acknowledged. Such are the alternating current equations, the Mass Action formulas, parts of the thermionic current discussion, and Fourier's equation for the flow of heat.

Some preparation in the sciences on the part of the reader is taken for granted in the presentation of the matter on this thesis. The …

A Model For Crystal Structure, Eugene E. Menge

Bachelors’ Theses

The problem of this thesis resolves itself into the following: To build a model to show the structure of crystals and to present- an explanation thereof.

The Making Of Models To Illustrate The Principle Of Plane Polarized Light And The Phenomenon Of Double Refraction., Milton A. Sizer

Bachelors’ Theses

When the author took a course in Optics, and came into contact for the first time with the subject of polarized light and double refraction, he found it exceedingly difficult to visualize the various phenomena which took place. The advantage could easily be seen, of mechanical models made to illustrate the passage of light through glass and other crystals. The object of this thesis is to describe the making of mechanical models which are to be used in teaching the subject of polarization of light.

Piezo-Electricity, Glen S. Sunderland

Bachelors’ Theses

The term "piezo" was derived from the Greek word "piezein", meaning "to press".

Piezo-electricity relates to the peculiar electric effect of pres.sure on some. crystals. The particular crystals evincing this phenomenon are of the class of hemihedral or hemimorphous, possessing the asymmetric arrangement of either the atoms or molecules.