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The Application Of The Membrane Analogy To The Solution Of Heat Conduction Problems, Lloyd Hines Wilson
The Application Of The Membrane Analogy To The Solution Of Heat Conduction Problems, Lloyd Hines Wilson
Masters Theses
"The purpose of this investigation is to determine the feasibility of applying the membrane analogy to the solution of two-dimensional heat conduction problems. This investigation will deal only with heat conduction in the steady state through homogeneous media"--Preface, page iii.
Reduction Of Beryllium Compounds With Magnesium, Pei Wang
Reduction Of Beryllium Compounds With Magnesium, Pei Wang
Masters Theses
"The purpose of this research was to investigate the thermal reduction of beryllium compounds and to devise a method to estimate the metallic beryllium content in the final product"--Introduction, page 1.
The Effects Of Moisture In Grog Upon Dry Pressed Mixes Containing Grog, Charles L. Mckinnis
The Effects Of Moisture In Grog Upon Dry Pressed Mixes Containing Grog, Charles L. Mckinnis
Masters Theses
"It has been found that the aging of clay-grog-water mixes before pressing proves to be quite beneficial. The purpose of the aging period is to allow the added water to disseminate throughout the mixture of clay (plastic) and grog (non-plastic) in an effort to bring about the best bonding action possible. The clay-grog-water mixture, if not aged, is of a sticky consistency; while, if the same mixture is aged for twenty-four (24) hours, it is readily workable. This process of aging has long been recognized as a "must" in the Ceramic Industry in obtaining mixtures of ideal workability"--Introduction, page 2.
A Study Of The Retort Zinc Distillation Process, Albert Hoffman
A Study Of The Retort Zinc Distillation Process, Albert Hoffman
Masters Theses
"The problem of this thesis is to determine the optimum density of packing of the charge to a zinc retort under exact industrial conditions of temperatures and materials as it affects the production of zinc metal. It is well known that the quantity of zinc produced per cycle is benefited by increasing the density of charging, but increased density of packing or charging is limited by the diffusion, through the charge of the gases necessary to carry on the reduction reactions. In commercial practice there is also a secondary limitation dependent primarily upon the rate at which the heat can …
Hysteresis Loss Of Supermalloy At Different Temperatures, Chester Ray Holland
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 Design, Construction, And Testing Of A Heat Exchanger For Determining Heat Transfer Coefficients For Liquids In Forced Convection Normal To Banks Of Staggered Tubes, Kenneth Edwin Rudert
The Design, Construction, And Testing Of A Heat Exchanger For Determining Heat Transfer Coefficients For Liquids In Forced Convection Normal To Banks Of Staggered Tubes, Kenneth Edwin Rudert
Masters Theses
"Many studies of heat transmission have been carried out on various kinds of heat exchangers. Film coefficients have been determined and the data correlated by equations. In particular, film coefficients have been obtained for gases in turbulent flow normal to both a single cylinder and banks of staggered tubes. Very little data has been published on liquid film coefficients for flow at right angles, or normal to banks of staggered tubes...It is the purpose of this paper to present the results obtained from tests made on an originally designed heat exchanger built in the laboratory. The exchanger is a non-baffled …
Liquid-Vapor Equilibria In The System Methanol-Ethylene Glycol-Water, John Wilson Sjoberg
Liquid-Vapor Equilibria In The System Methanol-Ethylene Glycol-Water, John Wilson Sjoberg
Masters Theses
"The freezing points of the system methanol-glycol-water were investigated by Conrad, Hill and Ballman to determine the suitability of such mixtures for use as an antifreeze. The low freezing points obtained seem to warrant further investigation of other properties of the system. Especially important would be the vapor-liquid equilibrium relations of the system, since one of the desirable features of such a mixture would be low vapor pressures. It is well known that when one substance is dissolved in another, each lowers the vapor pressure of the other. It was for the purpose of determining these relations that the present …
The Influence Of Cartridge Diameter On The Effectiveness Of Dynamite, Charles Harding Noren
The Influence Of Cartridge Diameter On The Effectiveness Of Dynamite, Charles Harding Noren
Masters Theses
"For many years the manufacturers of explosives have attempted to show the advantages of using dynamite of a cartridge diameter of at least 1-1/8 inches. Tests by the manufacturers and by the United States Bureau of Mines hare definitely shown that the dynamites prepared in larger diameter cartridges have several advantages: They are more sensitive to detonation; they detonate at a higher velocity; they are resistant to water; they are safer to use; and they are more stable than dynamites made in smaller diameter cartridges. In spite of these advantages listed, several large consumers still insist on smaller diameter cartridges. …
A Study Of The Separation Of Wolframite From Tin-Oxide, Chih-Wen Ying
A Study Of The Separation Of Wolframite From Tin-Oxide, Chih-Wen Ying
Masters Theses
"A number of mines in china, Bolivia, England, and other countries contain both tin-oxide and wolframite. Owing to the fact that the specific gravity of tin-oxide and wolframite is so nearly the same, considerable difficulty is experienced in making a gravity separation, and all attempts to do so by wet or dry concentration have given very poor results. The perfection of magnetic separators has done much to mitigate this difficulty, so that now complex ores of this nature can be treated in a satisfactory manner. The mixed concentrate from the tables or other concentrators, after being roasted to expel sulfur …
The Determination Of The Surface Tension Of Benzyl Ether, Sze-Kwei Min
The Determination Of The Surface Tension Of Benzyl Ether, Sze-Kwei Min
Masters Theses
"The accurate determination of surface tension is of importance in the investigation of theories of surface structure, the structure of liquids, molecular cohesion, in the study of colloids, especially in physiological work, and in various lines of technical chemistry. The two methods most commonly used for determining surface tension are the capillary rise method and the drop weight method. The theory of the former is simple, but its technique is difficult. Its use in some cases is the cause of errors as high as 30%, due to its inapplicability to certain classes of substance, and is much more sensitive to …
Synthesis Involving Waste Carbon Dioxide, Glenn Eldon Brand
Synthesis Involving Waste Carbon Dioxide, Glenn Eldon Brand
Masters Theses
"Many industries, ranging from power plants to breweries, produce large quantities of carbon dioxide as a by-product. The burning of limestone with natural gas produces a relatively clean gas in which the carbon dioxide content may exceed 40 per cent. It is with this type gas that the present thesis will be concerned. In this process the burning of the limestone is accomplished by using natural gas as a fuel, burning usually under a pressure of about two pounds, and obtaining carbon dioxide from the combustion of the gas and the decomposition of the limestone. Such a plant producing 70 …
The Effect Of Spontaneous Crystallization Of Some Inorganic Compounds At The Critical Temperature Of Their Solvents, John William Buttrey
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 …
The Kerr Electro-Optic Effect In Plastic Materials Transmitting Infra-Red Radiation, James Edson Dueker
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
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 Study Of The Transportation Of Mine Rock By Pumping, Howard Morris Fowler
A Study Of The Transportation Of Mine Rock By Pumping, Howard Morris Fowler
Masters Theses
"The conclusions arrived at in regard to the practicability of utilizing pumps instead of skip haulage for the removal of ore and waste from mines are entirely theoretical, as it was impossible to make actual conparative runs. These results were arrived at by comparing known or estimated costs for both types of operations. The abrasion studies were conducted in the laboratory of the Mining Department at the School of Mines and Metallurgy. The pressure tank was designed in an effort to counteract the present necessity for using single stage pumps in sand pumping, and to find a means for eliminating …
Rapid Determination Of Alumina In Diaspore Clays, Matthew Julius Kerper
Rapid Determination Of Alumina In Diaspore Clays, Matthew Julius Kerper
Masters Theses
"The alumina content of the diaspore clay is the index to its refractoriness, so it is important to know the alumina content of the diaspore clay. Diaspore is mined in comparatively small pits and naturally the alumina content will vary from pit to pit and will vary to a considerable extent in the same pit. Since a uniform finished product is desired, the alumina content of each pit must be known and frequent checks run on the output of the pits. Chemical analysis is the standard method of determining the amount of alumina in clays. The main objections to chemical …
A Study Of The Chemical Behavior Of Some Natural Occurring Iron Disulfide Ores, William Louis Shivelbine
A Study Of The Chemical Behavior Of Some Natural Occurring Iron Disulfide Ores, William Louis Shivelbine
Masters Theses
"A complete investigation of the pyrites deposits of Missouri by Grawe has revealed many large deposits of pyrites available in commercial quantities in the Ozark area. The pyrites has been found occurring in contact with several various types of minerals. In the northcentral Ozark Plateau, pyrites is found associated with hematite-bearing sink structures. In the northwest part of the state, pyrites occurs in coal deposits, which, in the future, may be recovered as a by-product in the production and preparation of coal. Some pyrites, chiefly marcasite, has been found as fracture and cavity fillings in several other districts. The purpose …
Beneficiation Of A Zinc Rich Oxidized Ore From Nuevo LéOn, MéXico, Jorge Casas Nieto
Beneficiation Of A Zinc Rich Oxidized Ore From Nuevo LéOn, MéXico, Jorge Casas Nieto
Masters Theses
"Rich zinc ores are relatively rare now in this country but are still abundant in countries like México, that have not yet developed all their mineral potentialities. In almost all Mexican zinc districts there has been reported sporadic production of oxidized ores, although until now no specially designed plants have been built for the beneficiation of such ores. Generally the zinc carbonate and zinc silicate ores are hand picked and shipped to this country for beneficiation. The Mexican production of zinc ores has never been steady, because of economic factors such as bad transportation systems and lack of market for …
The Effect Of Temperature On Mine Rocks, James Wilson Snider
The Effect Of Temperature On Mine Rocks, James Wilson Snider
Masters Theses
"The problem of this investigation involves the determination of the coefficients of thermal expansion of mine rocks, and the relationship of porosity, permeability, and consecutive temperature changes to the permanent elongation of those rocks. One of the major problems in mining today is that of the analysis of the action of exposed mine rock under changes of temperature. The immediate cause of a fall of ground in a mining excavation is due to the fact that some part of the mass that falls has been subjected to a stress beyond the strength of the rock. The question arises as to …
The Effect Of Rope Speed And Moisture On Mine Scrapers, Ronald L. Carmichael
The Effect Of Rope Speed And Moisture On Mine Scrapers, Ronald L. Carmichael
Masters Theses
"During recent years the use of power drawn scrapers, sometimes called "slushing", for the transfer of ore and waste rock has become standard practice in many mining operations. Scraper types have been developed to meet various operating conditions by trial and error methods and by practical research. The study of scraper efficiency has been confined in the past mainly to power consumption. A detailed study of the effect of rope speed and moisture content of the material being moved on scraping efficiency, under controlled conditions, has not been noted in a review of the literature. The author feels that such …
A Comparison Of The Use Of Polaroid And Colored Filters In The Multiplex Aeroprojector, Robert Greig Livingston
A Comparison Of The Use Of Polaroid And Colored Filters In The Multiplex Aeroprojector, Robert Greig Livingston
Masters Theses
"The purpose of this thesis is the drawing of a comparison between the use of the colored filters, which are normally employed in the multiplex aeroprojector by various mapping agencies throughout the country, and the use therein of Polaroid filters. The filters in the aeroprojector serve to break the projection of a stereoscopic pair of photographs into two impressions which are viewed separately by each eye of the observer, thus providing the main requirement for the observance of a three-dimensional effect. this stereoscopic effect is utilized in the multiplex plotting machine for the delineation of contours...In order to form a …
Geology Of The Einstein-Apex Tungsten Mine Area, Joel B. Pomerene
Geology Of The Einstein-Apex Tungsten Mine Area, Joel B. Pomerene
Masters Theses
"The geological problem existing in the Silver Mine area, the relationship of mineralization to structure, particularly to faulting and jointing, was pointed out to the writer by Prof. O. R. Grawe. Several geologists have made reconnaisance [sic] surveys of the whole region, but so far no detailed geologic map has been published of the immediate area. Prof. Grawe pointed out that such a map would be of value in the better understanding of the area and would be especially useful in the event that another national emergency required the development of all possible sources of tungsten"--Introduction, Selection of the Problem, …
An Investigation Of Various Properties Of The 60co-40cr Alloy, Roger David Moeller
An Investigation Of Various Properties Of The 60co-40cr Alloy, Roger David Moeller
Masters Theses
"The binary alloys of Co-Cr have had a few practical applications in our modern economy due to their high cost. The only extensive field of application has been developed in recent years in the manufacture of high temperature alloys for such equipment as gas turbines, jet engines, and turbo-superchargers. The use of these materials has been limited, due to their high cost, to small parts such as rotor blades in gas turbines. To reduce cost and to add desirable or eliminate undesirable properties, the binary alloys have, from the beginning, been modified with varying amounts of other metals. The modified …
The Solubility Of Copper In High-Iron And Low-Iron Slags, Charles Burroughs Gill
The Solubility Of Copper In High-Iron And Low-Iron Slags, Charles Burroughs Gill
Masters Theses
"A thesis giving the details of construction of a rotating induction furnace and its use to experimentally determine the amounts of copper absorbed in high-iron and low-iron slags at various temperatures. A rotating induction furnace is advantageous for slag study in that the slag is contained in a molten pure metal cup and does not come in contact with any refractory, which would be attacked by the slag and contaminate it. The molten pure metal cup is formed by melting the pure metal in a refractory crucible and spinning this inside an induction coil. The induction coil supplies heat for …
Further Studies On The Effect Of Grinding Aids For Portland Cement Clinker, Charles Lee Rakestraw
Further Studies On The Effect Of Grinding Aids For Portland Cement Clinker, Charles Lee Rakestraw
Masters Theses
"In the dry grinding of cement clinker to a fine powder in which for example ninety percent or more of the particles are reduced to a fineness below that of a 200 mesh screen, it has been found that further fine grinding is extremely difficult and the energy input is out of all proportion to the further production of fine particles. This seems to be due to the fact that when the bulk of the material reaches this fineness there is a tendency of the finest particles to cling to each other and bunch or flocculate. Along with this tendency …
Geology Of The Ozark-Martin Mine Area, Madison County, Missouri, William Clifton Hayes
Geology Of The Ozark-Martin Mine Area, Madison County, Missouri, William Clifton Hayes
Masters Theses
"General descriptions of the region adjacent to the Ozark and Martin Mines of Madison County, Missouri have been included in a number of early publications dealing with the Einstein Silver Mine area, but a detailed geologic map has not been made. It was thought that through detailed mapping and by a detailed analysis of all of the geologic features present, a more definite relationship between mineralization and structure might be determined"--Introduction, Purpose and Scope of Work, page 1.
The Use Of Wetting Agents In Clay Bodies, Nathan Russell Sewell
The Use Of Wetting Agents In Clay Bodies, Nathan Russell Sewell
Masters Theses
"It has been observed that one of the weak points in the present method of commercially preparing stiff mud bodies is the de-airing process, which involves passing them thru a vacuum chamber. Difficulties in maintaining a good vacuum, power costs, and work stoppages due to clogged vacuum chambers, are some of the problems. It was thought that perhaps a very definite contribution could be made in the field of ceramic engineering if some method could be devised for preparing a workable ceramic body of good dry and fired properties without the use of a vacuum chamber. In attacking the problem, …
Stresses In A Plate Having A Relatively Small Circular Hole And Loaded Parallel To The Axis Of The Hole Under Various Conditions Of Constraint With An Application To Deep Oil Wells, A. Dale Topping
Masters Theses
"The object of this investigation is to determine the stresses about a hole in a thick plate of large dimensions compared with the radius of the hole when the plate is loaded parallel to the axis of the hole under various conditions of restraint, and to apply the results to the case of a deep well. The case of a plate with an initial stress in its plane is also considered...The problem arose from difficulties encountered in the drilling of deep oil wells. After drilling has proceeded to a certain depth, the sides of the bore hole apparently collapse and …
Thermal Reduction Of Beryllium Chloride With Metallic Magnesium, Mailand R. Strunk
Thermal Reduction Of Beryllium Chloride With Metallic Magnesium, Mailand R. Strunk
Masters Theses
"The purpose of this research was to investigate the thermal reduction of beryllium chloride by metallic magnesium. Beryllium is a remarkable element, being characterized by its hardness, lightness and durability. Although the art of metallurgy has developed to a point at which most metals can be produced at a low cost, there are a few metals, of which beryllium is an outstanding example, which can only be obtained at high prices and in small amounts because of the difficulties of recovering the metals as such from their compounds which occur in nature. Small amounts of pure beryllium can be obtained, …
Performance Study Of Mechanical Loading Machines In Coal Mining Practice, Kor Uyetake
Performance Study Of Mechanical Loading Machines In Coal Mining Practice, Kor Uyetake
Masters Theses
"In the transition from hand-loading methods in coal mining to mechanical loading methods various types of equipment have been developed to do the same job. Among the coal mining operators and among miners in the coal fields, various equipment preferences have developed. This produces a sharp difference of opinion. emotional statements of such ideas based upon personal likings do not contribute materially to coal mining progress - it merely serves to confuse the issue. The author feels that the opinions on the loading equipment should be based upon some factual data rather than the preconceived idea. Often it is difficult …