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Articles 288541 - 288570 of 291657
Full-Text Articles in Physical Sciences and Mathematics
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.
Peactivity Of Alpha, Beta-Unsaturated Ethers With Grignard Reagents, Robert A. Walker
Peactivity Of Alpha, Beta-Unsaturated Ethers With Grignard Reagents, Robert A. Walker
Tennessee State University Alumni Theses and Dissertations
No abstract provided.
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 or Doctor of Nursing Practice
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 or Doctor of Nursing Practice
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 or Doctor of Nursing Practice
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 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 …
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, …
Preparation Of The Phenyl Urethans Of Saturated Aliphatic Liquid Alcohols And A Comparison Of Their Properties With Those Reported In The Literature, Mary Ann Mesoloras
Preparation Of The Phenyl Urethans Of Saturated Aliphatic Liquid Alcohols And A Comparison Of Their Properties With Those Reported In The Literature, Mary Ann Mesoloras
Bachelors’ Theses
An investigation of the phenyl urethans of saturated, aliphatic, liquid alcohols disclosed that there was a great discrepancy in the literature with regard to the melting points of these compounds. It was also found that the preparations of the phenyl urethans were either vague or specific for a few selected alcohols.
The purpose of this thesis was to prepare these derivatives in the laboratory in order to compare the melting points found to those in the literature.
Liquid Potassium Soaps From Coconut And Corn Oils, Jack R. Kaestner
Liquid Potassium Soaps From Coconut And Corn Oils, Jack R. Kaestner
Bachelors’ Theses
My interest in liquid potassium soaps began a number of years ago. At this time I was employed at a company that manufactured various cleaning preparations, one of these being a liquid soap prepared by the interaction of potassium hydroxide and cocoanut oil. It was there that I first became acquainted with techniques and problems encountered in the soap industry.
The above mentioned notes took place during the middle of World War II, and consequently the author became familiar with some of the different fats and oils that were substituted for the then unavailable Philippine coconut oil. All of the …
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.
A Study Of The Differential Seperation Of Galena And Sphalerite, Wilfred E. Nagel
A Study Of The Differential Seperation Of Galena And Sphalerite, Wilfred E. Nagel
Bachelors Theses and Reports, 1928 - 1970
The smelting of complex lead ores is a difficult operation, especially when they contain considerable amounts of iron and zinc. When these ores are smelted, all of the zinc, which is valuable and well worth recovering, goes into the slag. With the advent of the flotation processes, and the ability of these processes to concentrate the lead and zinc minerals into separate products, the smelting of complex lead ores was to a great extent simplified.
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 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.
The Preparation Of Alkyl Chlorobenzoates And Their Application As Alcohol Derivatives, Robert Gudwin Johnson
The Preparation Of Alkyl Chlorobenzoates And Their Application As Alcohol Derivatives, Robert Gudwin Johnson
Bachelors’ Theses
While engaged in the preparation of alcohol derivatives during a course in the characterization of organic compounds, the writer noticed in a chemical catalog that various chlorobenzoyl chlorides are now available commercially. Since many of the present reagents for the preparation of alcohol derivatives are deficient in at least one respect, it seemed to be a worthwhile project to prepare alkyl chlorobenzoates by the ·action of these substituted benzoyl chlorides on alcohols. A study of the physical properties of these chlorobenzoates would then be undertaken to determine the feasibility of using them as alcohol derivatives.
A search of the literature …
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.
The Darboux Inverse Problem In The Calculus Of Variations, Frank O. Lane
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
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
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.
A Mineral Dressing And Economic Study Of A Complex Arsenical Ore, Luigi D. Piana
A Mineral Dressing And Economic Study Of A Complex Arsenical Ore, Luigi D. Piana
Bachelors Theses and Reports, 1928 - 1970
The factors that influence the choice of a method for treatment of an ore comprise the technical and economic limitations and advantages, derived in detail and balanced according to the exigencies of the particular situation.
Separation Of Cadmium From Zinc In The Purification Step Of The Leaching Cycle, L. C. Powell
Separation Of Cadmium From Zinc In The Purification Step Of The Leaching Cycle, L. C. Powell
Bachelors Theses and Reports, 1928 - 1970
The purpose of this investigation is to determine the effect of the factors listed previously by conducting a series of tests that will indicate the extent to which the purification is influenced by time, temperature, zinc oust size, zinc dust quantity, iron concentration, two stage precipitation, and aeration.
The Chromatographic Separation Of Gilsonite, Harold Albert Bezzant
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 …
An Investigation Of The Precipitation Of Cobalt With Zinc Dust, Lyle Hallberg
An Investigation Of The Precipitation Of Cobalt With Zinc Dust, Lyle Hallberg
Bachelors Theses and Reports, 1928 - 1970
Cobalt, as well as copper, cadmium, and other impurities, is removed by selective precipitation with zinc during the zinc electrolyte purification cycle, and the purification residue may be treated by a Cadmium Plant for the recovery of cadmium.
Construction And Operation Of A Laboaratory Size Thum Cell, Raymond Dugdale
Construction And Operation Of A Laboaratory Size Thum Cell, Raymond Dugdale
Bachelors Theses and Reports, 1928 - 1970
Electrolytic silver refining was not perfected until the end of the nineteenth century. During the process of development, two systems of silver refining have come into prominence: the Moebius and the Thum types.
An Investigation Of Silicon Impregnation Of Low-Carbon Steels, Thomas E. Groce
An Investigation Of Silicon Impregnation Of Low-Carbon Steels, Thomas E. Groce
Bachelors Theses and Reports, 1928 - 1970
A problem of metallurgy during the last part of the Nineteenth and the early Twentieth Century, and one that stood very near the front, was investigations of methods to produce a non-corrosive surface on iron and steel without affecting the physical properties of these base metals.
A Study Of The Transformation Of A Twenty-Eight Per Cent Tin Bronze, Perry A. Boukind
A Study Of The Transformation Of A Twenty-Eight Per Cent Tin Bronze, Perry A. Boukind
Bachelors Theses and Reports, 1928 - 1970
In this investigation, attention is directed to the phases covered by a 28 per cent tin alloy. When the investigation was started, consideration was given to the possibility of making a Time - Temperature - Transformation curve for this particular alloy. As the work progressed and further research was carried on, this phase of the work was abandoned.
Chromizing Of Steels, Edward Buchanan
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.
Caustic Leaching Of Montana Chromite, Chester Freshour
Caustic Leaching Of Montana Chromite, Chester Freshour
Bachelors Theses and Reports, 1928 - 1970
Chromite is the most important ore used for the production of chromium and chromium alloys. At present, the domestic production is insignificant as compared with the amount of chromite consumed in the United States.
An Investigation Into The Precipitation Of Copper From Mine Water, Using Sulfur Dioxide To Reduce The Ferric Ion Content, David S. Gleason
An Investigation Into The Precipitation Of Copper From Mine Water, Using Sulfur Dioxide To Reduce The Ferric Ion Content, David S. Gleason
Bachelors Theses and Reports, 1928 - 1970
The experiments which were preformed showed that sulfur dioxide would reduce the ferric ion content of the mine waters to a very low figure. The reduction in the ferric ion content would improve the efficiency of the precipitation process, and also increase the recovery of copper.
Application Of The Electric Furnace To The Melting Of Cathode Copper At The Tacoma Smelter, Alvin H. Nelson
Application Of The Electric Furnace To The Melting Of Cathode Copper At The Tacoma Smelter, Alvin H. Nelson
Bachelors Theses and Reports, 1928 - 1970
In the field of copper metallurgy, the major changes effected in the original metallurgical scheme have been based largely upon the lowering in grade of copper ores, and the more particular demands of the fabricators of the metal. The former trend fostered the development of mineral beneficiation, which in turn caused the conversion from blast furnace to reverberatory furnace smelting.