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Articles 289261 - 289290 of 292638
Full-Text Articles in Physical Sciences and Mathematics
Analytical Data, Walter A. Lawrance
Some Reactions Of Tris (Hydroxymethyl) Aminomethane, Ralph Walton Raiford
Some Reactions Of Tris (Hydroxymethyl) Aminomethane, Ralph Walton Raiford
Master's Theses
Most of the work on alkanolamines has been confined to the preparations and reactions of the ethanolamines. The results reported herein deal with the reactions of H2NC(CH2OH)3, tris(hydroxymethly)aminomethane, which is a beta-hydroxy amine.
An Electrochemical Determination Of The Thermodynamic Properties Of Silver And Mercury Sulfides, Arthur G. Cole
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.
Semigroup Ideals, Kenneth Scott Carmen
Semigroup Ideals, Kenneth Scott Carmen
Masters Theses
In the literature of ideals a left ideal L of a system S has usually been defined by the inclusion of SL ⊆ L and a right ideal R by the inclusion RS ⊆ R. On the other hand a left zero element z is usually defined by the equation za = z and a right zero element by the equation az = z ; similarly a left or right identity element e is defined by the equation ea = a or ae = a respectively. The author has in this paper made the terms left and right when applied …
Factors Influencing The Solubility And Oxidation Of Commercial Iron Pyrites, Neldon Lamont Jensen
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.
Direct And Semidirect Products Of Semigroups, John Charles Harden
Direct And Semidirect Products Of Semigroups, John Charles Harden
Masters Theses
The purpose of this thesis is to exhibit the direct products and the semidirect products of semigroups of orders two, three, and four. Section I consists of the definitions necessary for the proofs and computations which appear in the first five sections. In Section 2 theorems on direct products of semigroups of any order are proved. A method of writing by inspection the multiplication table of the direct product of two finite semigroups is presented in Section 3. Section 4 consists of tables listing the direct products of semigroups of order two with semigroups of orders two, three and four …
Endomorphisms And Translations Of Semigroups, Eldon E. Posey
Endomorphisms And Translations Of Semigroups, Eldon E. Posey
Masters Theses
This thesis is a study of some of the properties of mappings or semigroups into semigroups. In Section 1, definitions and basic concepts are given, with brief mention of some well known properties of semigroups and of mappings. Section 2 is devoted to a few theroems which are useful in the process of finding the semigroup of all endomorphisms of a given semigroup. When theorems on endomorphisms are valid in the more general situation in which a semigroup is mapped homomorphically on another semigroup, we state and prove the theorems in the more general setting. Section 3 consists of some …
An Investigation Of The Radioactivity Of Oilwell Drilling Fluid, With Depth, Of Wells In The Berland Field Of Rooks County, Milford W. Johnston
An Investigation Of The Radioactivity Of Oilwell Drilling Fluid, With Depth, Of Wells In The Berland Field Of Rooks County, Milford W. Johnston
Master's Theses
In reviewing the foregoing literature and in consideration of the very important place of the state of Kansas in the nation's production of petroleum, it was thought that possibly a contribution might be made to the general subject of geophysical prospecting for oil by the adoption and execution of the problem proposed by the title of this thesis. Since a similar but more scattered study of this problem had been previously made by Lippert with the use of an electroscope, it was considered worth-while to repeat the electroscopic observations together with Geiger-Mueller Counter observations on a new series of wells …
A Determination Of The Decomposition Potential Of Sulfamic Acid And Certain Of Its Metallic Salts, Francis J. Shell
A Determination Of The Decomposition Potential Of Sulfamic Acid And Certain Of Its Metallic Salts, Francis J. Shell
Master's Theses
The present investigation of decomposition potentials, or the potential where continuous electrolysis begins, was suggested by a paper by Choguill (5) on the electrodeposition of some metals from solutions of their sulfamates. Sulfamic acid or amidosulfonic acid H2N•SO2•OH is a strong inorganic acid obtained from chlorosulfonic acid and ammonia, or by heating urea with fuming sulfuric acid. The latter process is now used on a commercial scale. The acid forms white or colorless non-hygroscopic crystals that are stable when dry but in solution at elevated temperatures it slowly hydrolyzes forming ammonium bisulfate.
A Study Of Aldehyde Derivatives Of Metallic Sulfamates, Edmond A. Morin
A Study Of Aldehyde Derivatives Of Metallic Sulfamates, Edmond A. Morin
Master's Theses
Sulfamic acid at one time had no particular value, and very little was known about the physical and chemical properties of this acid. At the present time , however, this acid is a commercial product of considerable importance and extensive investigation has been conducted to discover its many chemical properties. A very interesting group of compounds derived from sulfamates are the aldehyde addition products. The aldehyde derivatives of calcium sulfamate were studied and had a particular interest because of their greater stability, especially in the isolated, solid form. The aldehyde addition products of calcium studied included benzaldehyde, furfuraldehyde, for aldehyde, …
The Reactions Of Ethyl Acetoacetate With Certain Halogen Derivatives Of Alcohols, Harold E. Sullivan
The Reactions Of Ethyl Acetoacetate With Certain Halogen Derivatives Of Alcohols, Harold E. Sullivan
Master's Theses
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 …
Solid Reactions: The Influence Of Temperature And Concentration, Norman H. Kowert
Solid Reactions: The Influence Of Temperature And Concentration, Norman H. Kowert
Bachelors’ Theses
Reactions are constantly taking place all around us. They are the basis of chemistry. Without reactions, there could be no change, and, therefore, no chemistry. Most reactions can be easily visualized; as, for instance, when two liquids are mixed together, or two gases, or a gas and a liquid. When reactions between these substances take place, we take it as a matter of course. There is another type of reaction, however, which does take place, but which is not easily visualized. This is the reaction between two solid substances. Due in part to the nature of solids, their crystalline form, …
Methylchlorosilanes, Donald Edward Campbell
Methylchlorosilanes, Donald Edward Campbell
Honors Theses
The primary objective of this investigation was to prepare and improve the separation of the mono and di-methyl substituted chlorosilanes by fractional distillation.
The Preparation And Attempted Polymerization Of Beta-Chlorostyrenes, Curtis Usher Coleman
The Preparation And Attempted Polymerization Of Beta-Chlorostyrenes, Curtis Usher Coleman
Honors Theses
The polymerization of unsubstituted styrenes had been studied by a number of worker, among them Wheland (11), Stoermer and Kootz (9), and Ziegler and Bahr (13), but none of these workers have studied the effect of halogen substitution on the side chain. This has been studied by Worrall (12), and he concluded that such substitution blocked polymerization. It was the purpose of the present work to prepare α-chlorostyrene, and to carry the work of Worrall a step further by seeking some reagent which would bring about the polymerization of α-chlorostyrene. A further purpose was to prepare a new α-chlorostyrene, determine …
Some Colloidal Aspects Of Portland Cement, Eugene D. Day
Some Colloidal Aspects Of Portland Cement, Eugene D. Day
Honors Theses
Excellent general discussions of the earlier literature concerning the rival crystallization and colloid theories as applied to the setting and hardening of Portland cement are found in Bogue (4, 5), Kuhl (21), and Lea and Desch (24). These authors, along with Steinour (41), have tried to resolve these apparently conflicting hypotheses in the light of more recent investigations and have clearly outlined those areas of conflict which need further clarification through continued research. Recent work by Hedin (16) has shown that when ion concentrations and ion activities in solution are changed by the addition, for example, of gypsum, a sufficiently …
The Measurement Of Dipole Moments, Anthony Martin Di Cocco
The Measurement Of Dipole Moments, Anthony Martin Di Cocco
Honors Theses
It is the purpose of this thesis to present an outline or the determination of dipole moments according to the Heterodyne-Beat method, as a laboratory exercise in Physical Chemistry.
Kinetics Of Displacement Reactions Which Result In A Retention Of Configuration, Victor Frank Mattson
Kinetics Of Displacement Reactions Which Result In A Retention Of Configuration, Victor Frank Mattson
Honors Theses
Depending upon the halogenating agent and the reaction conditions d-ethyl medelate may form either d - or 1-ethyl phenylchloroacetate. Situations of this type are common and have proven to be an interesting and a productive field for investigation into the mechanisms of organic substitution reactions. The inversion reaction (Walden Inversion) appears to be the more typical of the two and is also the more readily explained. A and B ions have a repulsive effect upon each other and classical theory would demand that the ion B enter the molecule on the side opposite A. This displacement would of necessity result …
Synthesis Of Methyl Chlorsilanes, Arthur E. Lessor Jr.
Synthesis Of Methyl Chlorsilanes, Arthur E. Lessor Jr.
Honors Theses
The reaction of methyl magnesium chloride and methyl magnesium iodine with silicohloroform gave a mixture of methyl dichlorsilane, dimethyl chlorsilane, trimehtyl silane, and an unfientified high boiling liquid which gave no chlorine on analysis.
Viscosity-Temperature Relations Of Naphthalene In Benzene, Leighton Hartwell Peebles Jr.
Viscosity-Temperature Relations Of Naphthalene In Benzene, Leighton Hartwell Peebles Jr.
Honors Theses
A study was made of multi-benzene ring compounds dissolved in benzene in order to discover any relationship between viscosity, density, and temperature. However, as there was insufficient time, only solutions of naphthalene dissolved in benzene were studied.
Taurine, George William Schnabel
Taurine, George William Schnabel
Honors Theses
This thesis is a primary investigation into a new synthesis of taurine. The sulfite of ethylene glycol is reacted with ammonium hydroxide to produce taurine.
The Determination Of Particle Terminal And Transport Velocities, Bertram C. Raynes
The Determination Of Particle Terminal And Transport Velocities, Bertram C. Raynes
Honors Theses
The movement of finely divided material in chemical process equipment is becoming the object of much present-day study. In industrial practice, the ability to predict the behavior of small bodies moving through a fluid medium or being moved by a fluid medium must be based upon data relating to physical properties of both the particle and the fluid; these physical properties should be those which can be readily determined.
A particle falling through a fluid medium will achieve a steady state velocity if it is allowed to fall until its acceleration becomes zero. This steady state rate of fall is …
The Effect Of Heat Aging Upon Silicone Rubber Compounds, Jonathan Rodney Learn
The Effect Of Heat Aging Upon Silicone Rubber Compounds, Jonathan Rodney Learn
Honors Theses
Silicone rubber compounds are high temperature rubber-like materials consisting of silicone gum, a filler, and a curing catalyst. The filler is added to the rubber to give good molding properties and also good tensile strength and elongation. The data in this thesis shows that the compounds which had the best heat aging properties consisted of 100 parts of silicone rubber and 0.5 parts of' benzoyl peroxide as the curing catalyst, with titanium dioxide as the filler.
The Catalytic Vapor Phase Alkylation Of Phenol By Alcohols, Robert Lemieux
The Catalytic Vapor Phase Alkylation Of Phenol By Alcohols, Robert Lemieux
Honors Theses
The object of this research is to study the reactions between phenol and various alcohols, using an activated alumina catalyst, at a temperature of 325 degrees Celsius. The alcohols, which are studied, are methyl, ethyl, and benzyl alcohol, respectively.
Petrography Of The Chilhowee Group, Near Walland, Tennessee, George David Swingle
Petrography Of The Chilhowee Group, Near Walland, Tennessee, George David Swingle
Masters Theses
Introduction: Time and the stratigraphic relationships of the Ocoee and Chilhowee groups have long been a problem in southern Appalachian geology. These rocks, now metamorphosed to varying degrees, outcrop over wide areas in the mountain region. Unfortunately, no one person has been able to study their problems in enough detail to unravel them and, as a result, many conflicting statements are in the literature.
Formations of the Ocoee and Chilhowee groups are largely composed of fine to coarse clastic sediments. In general, rocks of the Ocoee group lie to the southeast; those of the Chilhowee group to the northeast. The …
The Possibility Of Using Gelatin As A Substrate In Determining The Effect Of Ph On The Activity Of Hyaluronidase, Robert P. O'Driscoll
The Possibility Of Using Gelatin As A Substrate In Determining The Effect Of Ph On The Activity Of Hyaluronidase, Robert P. O'Driscoll
Bachelors’ Theses
The aim of this research is as follows:
- To determine the feasibility of using gelatin as a substrate for hyaluronidase.
- To determine the optimum pH for the enzyme acting upon a gelatin substrate.
- To determine qualitatively and quantitatively if reducing sugars are present in the substrate after action by the enzyme.
The work on hyaluronidase is relatively new. However it is the most extensively studies mucolytic enzyme.
A Study Of Atmospheric Ozone Near The Surface Of The Earth, Irby Gerald Bowen
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 Effect Of Certain Reagents On The Consolute Temperature Of The Phenol And Water System, Donna Louise Bleck
The Effect Of Certain Reagents On The Consolute Temperature Of The Phenol And Water System, Donna Louise Bleck
Bachelors’ Theses
The phenol water system was one of the first of a number of partially miscible liquid systems to be investigated. The mutual solubility has been determined for the pure system at various temperatures and pressures by many investigators.
Particularly interesting is the effect of the addition of a third substance on the mutual solubility of this system.
It is, the purpose of this work to determine the effect of certain previously untried substances on the mutual solubility of phenol and water by investigation of the critical solution temperature before and after their addition. The compounds used have been selected on …
Study Of Ether Soluble Factor From Urine Capable Of Reducing The Viscosity Of Gelatin, Lawrence H. Docta
Study Of Ether Soluble Factor From Urine Capable Of Reducing The Viscosity Of Gelatin, Lawrence H. Docta
Bachelors’ Theses
Leonard Driss reported that urine contained an ether soluble factor capable of reducing the viscosity of a gelatin solution.
This thesis intends to further investigate-this point · and to determine the nature of the viscosity reducing factor. Also, to further investigate the phenomena reported by Driss that male urines obtained soon after emission had a greater amount of this viscosity reducing factor than normal urine.
A Study Of Steric Inhibition Of The Pfitzinger Reaction, Robert Earl Stobaugh
A Study Of Steric Inhibition Of The Pfitzinger Reaction, Robert Earl Stobaugh
Masters Theses
(From Introduction)
A survey of the Pfitzinger reaction reveals that little attention has been given to the steric factors likely to govern the course of the condensation; a major part of the research done has dealt with its value as a synthetic tool.
The primary purpose of this work was to add further information concerning steric inhibition in the Pfitzinger reaction; it was also hoped that the cinchoninic acids obtained might show physiological activity.
The Christensen Sillimanite Deposit Southeast Of Dillon, Montana, Everett O. Bracken
The Christensen Sillimanite Deposit Southeast Of Dillon, Montana, Everett O. Bracken
Bachelors Theses and Reports, 1928 - 1970
The minerals sillimanite, kyanite, andalusite, dumortierite, and topaz comprise a group of minerals whose high alumina content and physical properties are particularly desirable in the manufacture of refractory products. Sillimanite is the least plentiful of the minerals of this group, and for this reason it is not used extensively at the present time. However, it would be very desirable to the refractory industry if a suitable domestic source of supply could be established.