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Further Studies Of The Reactions Of Quinoxaline, 2-Methyl-, And 2,3-Dimethylquinoxaline, Chester E. Hamilton Jan 1950

Further Studies Of The Reactions Of Quinoxaline, 2-Methyl-, And 2,3-Dimethylquinoxaline, Chester E. Hamilton

Theses and Dissertations

A long term research program into the chemistry of quinoxalines has been instituted at Brigham Young University. The literature of quinoxaline chemistry was reviewed and assembled in one paper. Methods of preparation of 2,3-dimethyl- and 2- methylquinoxaline were studied and improved. The bromination of 2,3-dimethylquinoxaline using N-bromosuccinimide was accomplished and an anil addition using quinoxaline and phenyllithium was achieved. Efforts to prepare vinylquinoxalines were unsuccessful. In order to pursue an investigation into the numerous reactions of the 1,4 addition type, a method of preparations of vinyl-quinoxalines must be achieved. In the present investigation, various methods of synthesis of vinyl- and …


The Application Of High Frequency Oscillations To Chemical Analysis., Thomas Shepherd Burkhalter Jan 1950

The Application Of High Frequency Oscillations To Chemical Analysis., Thomas Shepherd Burkhalter

LSU Historical Dissertations and Theses

No abstract provided.


Some Physical And Chemical Properties Of Loess Deposits In The Lower Mississippi Valley., Ellis Louis Krinitzsky Jan 1950

Some Physical And Chemical Properties Of Loess Deposits In The Lower Mississippi Valley., Ellis Louis Krinitzsky

LSU Historical Dissertations and Theses

This study presents a general picture of loess in the Lower Mississippi Valley. Loess is recognized as unstratified, calcareous, slightly plastic, porous loam with an average grain size distribution between 0.05 and 0.01mm. diameter. Materials meeting this definition but lacking in calcium carbonate are termed "leached loess" when in association with loess and "brown loam" when not in association with loess.

Loess has been found to occur chiefly as pseudo-anticlinal caps on hills. It is mapped as occurring within an area averaging 10 to 15 miles in width extending from southern Illinois southward along the eastern walls of the Lower …


Quaternary Geology Of Southeast Texas., Hugh Allen Bernard Jan 1950

Quaternary Geology Of Southeast Texas., Hugh Allen Bernard

LSU Historical Dissertations and Theses

No abstract provided.


Studies In The Application Of Extraction Methods To Analytical Chemistry., Jack Kenneth Carlton Jan 1950

Studies In The Application Of Extraction Methods To Analytical Chemistry., Jack Kenneth Carlton

LSU Historical Dissertations and Theses

No abstract provided.


Selected Studies Of Organic Reagents., Louis Johnson Conrad Jan 1950

Selected Studies Of Organic Reagents., Louis Johnson Conrad

LSU Historical Dissertations and Theses

No abstract provided.


The Synthesis And Insecticidal Activity Of Some Halogenated Aromatic Ethers., Tien-Chih Chen Jan 1950

The Synthesis And Insecticidal Activity Of Some Halogenated Aromatic Ethers., Tien-Chih Chen

LSU Historical Dissertations and Theses

No abstract provided.


A Petrographic Study Of The Eocene Jackson Group Of Mississippi And Adjacent Areas., Ming-Shan Sun Jan 1950

A Petrographic Study Of The Eocene Jackson Group Of Mississippi And Adjacent Areas., Ming-Shan Sun

LSU Historical Dissertations and Theses

No abstract provided.


The Conservation Of Systems In Phase Space As Applied To The Liquid State., Ernest Ikenberry Jan 1950

The Conservation Of Systems In Phase Space As Applied To The Liquid State., Ernest Ikenberry

LSU Historical Dissertations and Theses

No abstract provided.


The Determination Of The Solubility Of Hafnium Oxide In Aqueous Solution By The Radioactive Tracer Technique, Hampden O. Banks Jan 1950

The Determination Of The Solubility Of Hafnium Oxide In Aqueous Solution By The Radioactive Tracer Technique, Hampden O. Banks

Masters Theses

"To date, there is no information in the open literature concerning the solubility of hafnium oxide in water other than the fact that it is very insoluble. This lack of experimental information is due, partly, to the fact that hafnium is a relatively new addition to the list of known elements"--Introduction, page 1.


Intermolecular Potential Functions For Liquid Argon And Liquid Mercury, Richard H. Kerr Jan 1950

Intermolecular Potential Functions For Liquid Argon And Liquid Mercury, Richard H. Kerr

Masters Theses

"The purpose of this research is to obtain such intermolecular potential functions for liquid argon and liquid mercury by use of the experimental radial density functions available for these two liquids over a wide range of temperatures. We shall introduce the notion of a correlation between the motions of atoms in neighboring cells in a cell theory of liquid structure, and derive a theoretical radial density function involving the intermolecular potential function for a pair of atoms in the liquid. This radial density function, or as it is frequently termed, the atomic distribution function, applied to the experimental data should …


A Determination Of The Surface Tension Of Bismuth, Cadmium, Tin, And Lead, Edward Mckee Chandler Jan 1950

A Determination Of The Surface Tension Of Bismuth, Cadmium, Tin, And Lead, Edward Mckee Chandler

Masters Theses

"Various methods have been employed for the determination of surface tension including capillary rise, drop weight, maximum bubble pressure, sessile drops on flat surfaces, sessile bubbles formed underneath flat surfaces, and the shape of pendent drops. Each method is subject to characteristic advantages and disadvantages. Only two of these will be discussed. The method of maximum bubble pressure allows the formation of a fresh surface for every bubble but does not permit the study of a given sample over a period of time. The sessile drop in direct contrast, allows the observation of the same sample over any period of …


The Reflection Coefficient At The Truncated Corner Of A Rectangular Wave Guide, John Raymond Barcroft Jan 1950

The Reflection Coefficient At The Truncated Corner Of A Rectangular Wave Guide, John Raymond Barcroft

Masters Theses

"The term wave guide refers to a hollow conducting tube (usually of rectangular or circular cross section) filled with a dielectric (or vacuum) and used for the transmission of electromagnetic waves. We shall consider the guide to be bounded by a perfect conductor and to be filled with a lossless homogeneous isotropic dielectric (or vacuum). The electromagnetic wave in the guide must of course satisfy Maxwell's equation. It must also satisfy the boundary condition that there be no tangential component of electric field at the surface of the conductor. If the electromagnetic waves traveling along the guide meet a discontinuity …


The Theory Of The Specific Heat Of A Body Centered Cubic Lattice, Curtis Cleveland Webster Jan 1950

The Theory Of The Specific Heat Of A Body Centered Cubic Lattice, Curtis Cleveland Webster

Masters Theses

"In normal crystalline solids the atoms are at rest in their lattice points at absolute zero of temperature. Increasing the temperature of the crystal increases the motion of the atoms about their lattice points. Approximately, each atom or ion may be treated as a harmonic oscillator. then from the equations of motion of the atoms, by the Born-von Karman theory of specific heats, the normal modes of vibration of the lattice can be expressed as the roots of a secular determinant. Application of this theory to determine the thermodynamic properties of crystals has resulted either in solutions that are inaccurate …


The Theory Of The Specific Heat Of A Face-Centered Cubic Lattice, Charles Robert Bonnell Jan 1950

The Theory Of The Specific Heat Of A Face-Centered Cubic Lattice, Charles Robert Bonnell

Masters Theses

"It is generally accepted that a normal crystalline solid can be pictured at absolute zero as an assembly of atoms at rest arranged at periodic lattice points. Since at higher temperatures each molecule becomes a harmonic oscillator about its lattice point, it is necessary to know the distribution of normal modes of vibration in order to calculate the thermodynamic properties of the lattice...Many approaches have been made to get a simple solution of the problem, but either accuracy is sacrificed for simplicity, or the solutions demand a very considerable amount of labor. The classical theories failed to explain the change …


An Electrochemical Determination Of The Thermodynamic Properties Of Silver And Mercury Sulfides, Arthur G. Cole Sep 1949

An Electrochemical Determination Of The Thermodynamic Properties Of Silver And Mercury Sulfides, Arthur G. Cole

Theses and Dissertations

The problem consists of measuring accurately the free energy of formation, heat of formation, entropy, and solubility product constant of silver and mercury sulfides, and is a part of a larger study extending to many other metal sulfides. The confusion now existing in the chemical literature amply justifies a study of this nature. The thermodynamic properties of several important metal sulfides have never been measured, and the only values available for them are estimates. Determinations of the properties of many other metal sulfides have been carried out, but the results given by different authors often differ widely.


Factors Influencing The Solubility And Oxidation Of Commercial Iron Pyrites, Neldon Lamont Jensen Aug 1949

Factors Influencing The Solubility And Oxidation Of Commercial Iron Pyrites, Neldon Lamont Jensen

Theses and Dissertations

Studies were made (1) to determine the effect of air and oxygen and verying concentrations in distilled water, on the solubility of iron pyrites; (2) to determine the effect of acid, base and buffer solutions of varying pH; (3) to observe the effect of some oxidizing and reducing agents on the solubility of iron pyrites. These investigations would aid in deciding the possibilities of using iron pyrites as a soil conditioner.


The Reactions Of Ethyl Acetoacetate With Certain Halogen Derivatives Of Alcohols, Harold E. Sullivan Jul 1949

The Reactions Of Ethyl Acetoacetate With Certain Halogen Derivatives Of Alcohols, Harold E. Sullivan

Master's Theses or Doctor of Nursing Practice

Chemical literature records many series of compounds produced by the acetoacetic ester synthesis, but in no instance is combination of the acetoacetic ester with the halogenated alcohols, of which the chlorohydrins are examples, mentioned. The products of these reactions are substituted derivatives of the acetoacetic ester. These products yield, upon hydrolysis, hydroxy-ketones. These acids and ketones may serve as intermediates for synthesizing other compounds. Many compounds which have medicinal value, such as pyrazolones and other ring compounds, may be synthesized from the acetoacetic ester derivatives. This study of the reactions of the acetoacetic ester with certain halogen derivatives of alcohols …


A Study Of Atmospheric Ozone Near The Surface Of The Earth, Irby Gerald Bowen Jun 1949

A Study Of Atmospheric Ozone Near The Surface Of The Earth, Irby Gerald Bowen

Physics & Astronomy ETDs

It is the primary purpose of this thesis to describe the method used for measuring ozone at the earth’s surface. There is also a report on a brief series of surface ozone measurements. An attempt is made at a preliminary explanation on the basis of meteorological conditions of the diurnal variations which were found.


The Darboux Inverse Problem In The Calculus Of Variations, Frank O. Lane May 1949

The Darboux Inverse Problem In The Calculus Of Variations, Frank O. Lane

Mathematics & Statistics ETDs

The simplest non-parametric problem of the calculus of variation, the so-called direct problem of the plane, is the problem of finding that arc Co of a family of admissible arcs y=y (x) joining two fixed pointed (x1 , y1 ), (x1, y2) in the x,y-plane such that along the Co the integral takes on a minimum value.


A Study Of Magnesium Silicate As A Base Matrix Material For Fluorescent Materials, John D. Hopperton May 1949

A Study Of Magnesium Silicate As A Base Matrix Material For Fluorescent Materials, John D. Hopperton

Chemistry and Chemical Biology ETDs

Luminescent materials have come into wide and important use within the past ten years in such equipments as the fluorescent lamp, and the cathode ray television tube. Because of this wide interest and usage, there has been made a concentrated search for ever brighter luminescent materials. It has also been of importance to produce and investigate materials which would produce as a wide range of colors under excitation as possible.


A New Method Of Measuring The Intensity Of The Zodiacal Light, Raymond Grenchik May 1949

A New Method Of Measuring The Intensity Of The Zodiacal Light, Raymond Grenchik

Physics & Astronomy ETDs

The two theories that have been presented for the zodiacal light show that it is due to light scattered (and perhaps emitted) from an extensive lenticular cloud of particles lying in the plane of the ecliptic. The basic difference of the two theories is the position of the center of this cloud. One, the planetary theory, places the sun at the center of this cloud. The other, the atmospheric theory, places the earth at the center of the cloud.


The Chromatographic Separation Of Gilsonite, Harold Albert Bezzant May 1949

The Chromatographic Separation Of Gilsonite, Harold Albert Bezzant

Theses and Dissertations

Separation of natural hydrocarbon minerals into their constituents non-destructively is a very difficult problem. A non-destructive analysis of the hydrocarbon minerals is essential to their wise utilization. Chromatography represents a non-destructive means of separating adsorbable substances non-destructively with a high degree of purity. The chromatographic separation is based upon the simple principle of the difference in adsorption affinity of compounds for a particular adsorbent. The chromatographic separation of gilsonite was, therefore, undertaken in an effort to prove that the adsorbable compounds of this hydrocarbon mineral could be separated by this simple non-destructive method. The first chromatographic columns of alumina, silica …


Chromizing Of Steels, Edward Buchanan May 1949

Chromizing Of Steels, Edward Buchanan

Bachelors Theses and Reports, 1928 - 1970

In recent years, considerable thought and study have been given to the use of chromized articles in place of chromium stainless steel articles. The present extensive application of chromizing, indeed, helps greatly to conserve this valuable metal.


A Cosmic Ray Experiment Using Nuclear Photographic Emulsions, Mercedes Merner May 1949

A Cosmic Ray Experiment Using Nuclear Photographic Emulsions, Mercedes Merner

Physics & Astronomy ETDs

A "camera" containing thirty-six nuclear plates was carried into the upper atmosphere to an altitude of twelve miles by a free balloon flight. These plates were arranged in four groups separated by successively thicker layers of steel so that nuclear events under different amounts of matter could be observed.

After recovery of the equipment these plates were developed and examined under the microscope. Four plates were selected for intensive investigation, and data was collected on the tracks found in the areas examined.

In the first part of this report nuclear plate technique will be discussed in general together with the …


A Nuclear Magnetic Resonance Absorption Experiment, Richard Runge May 1949

A Nuclear Magnetic Resonance Absorption Experiment, Richard Runge

Physics & Astronomy ETDs

In nuclear magnetic resonance absorption work, the detection of the absorption of energy by protons situated in a steady strong magnetic field and subject to a weak radiofrequency (RF) magnetic field is attempted. The protons are present in a sample placed inside an RF coil. A radiofrequency current, present in this coil, produces a rapidly oscillating magnetic field which is capable of supplying energy to the system of protons in the steady strong magnetic field. This absorption of energy by the protons alters their relative numerical distribution among the energy levels available to them.


The Preparation Of M-Ethylphenol And M-Phenylphenol From Resorcinol, Ronald Kenith Robins May 1949

The Preparation Of M-Ethylphenol And M-Phenylphenol From Resorcinol, Ronald Kenith Robins

Theses and Dissertations

The lack of a convenient method for the synthesis of m-alkylphenols has long been recognized by organic chemists. Within recent years the study of the physiological properties of these compounds and their derivatives, particularly the curare analogues, has caused much more concern to be placed upon a satisfactory method of synthesis. The problem of their synthesis offered an interesting study in synthetic organic chemistry. Both groupd, the alkyl group and the hydroxyl group of a meta-alkylated phenol, direct to the ortho and para positions. This makes it impossible to prepare the m-alkylphenols by the usual procedures employed in the synthesis …


The Monadnock Volume 23, Number 2, May 1949, Clark University Geographical Society May 1949

The Monadnock Volume 23, Number 2, May 1949, Clark University Geographical Society

The Monadnock (Clark Geographical Society)

Volume 23, Issue 2 of The Monadnock. The Monadnock was the alumni magazine of the Clark University Geographical Society (1927-1985) (2014-present).


The Sixty-First Session Of The Iowa Academy Of Science, April 15 And 16, 1949, Iowa Academy Of Science Apr 1949

The Sixty-First Session Of The Iowa Academy Of Science, April 15 And 16, 1949, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


The Determination Of Hydrogen Numbers Of Various Olefins And Unsaturated Fatty Acids Using A Semi-Micro Hydrogenation Apparatus And To Compare These Numbers To Their Iodine Numbers, Francis J. Romeo Apr 1949

The Determination Of Hydrogen Numbers Of Various Olefins And Unsaturated Fatty Acids Using A Semi-Micro Hydrogenation Apparatus And To Compare These Numbers To Their Iodine Numbers, Francis J. Romeo

Bachelors’ Theses

Many important industrial applications for fatty acids and their derivatives are based on the ability of the unsaturated members of a series to combine with other molecules through the reactivity of their double bonds.

Investigators for quite some time have sought means and methods for determining the number and the position of these double bonds and correlating the results as a means of identification for the unsaturation in fats and oils. Iodine addition to the double bond is employed generally in analytical work as a measure of unsaturation and as a means of separating acids of varying degrees of unsaturation. …