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Prospecting, Developing, And Mining Bentonite Deposits, John Patrick Rasor
Prospecting, Developing, And Mining Bentonite Deposits, John Patrick Rasor
Masters Theses
"Clay and clay-like minerals are mined in many localities for a large number of uses. Most of these mines are small, seasonal operations. Common practice in these types of pits is to strip and mine clay from shallow overburden depths without the aid of careful prospecting and developing, and with little or no engineering technique. Bentonite deposits which must be continuously mined at tonnages from 5,000 to 7,500 tons per month require that the entire project be carefully planned and engineered so suitable equipment may be obtained and operational cost minimized. This thesis is concerned with the prospecting, developing, and …
Flotation Of The Oxidized Ores Of Zinc, Fred Henry Bunge
Flotation Of The Oxidized Ores Of Zinc, Fred Henry Bunge
Masters Theses
"There is no satisfactory method of concentrating the finely disseminated oxide ores of zinc. Gravity methods of concentrating such ores may be used for coarsely crystalline materials in which the zinc material is free at approximately 10- to 35-mesh or coarser. In addition, gravity methods of concentration do not give a satisfactory separation on those ores in which the gangue mineral is small. As a result there is need for a method of beneficiating various deposits of oxidized zinc ores. The two commercially important oxidized zinc minerals under consideration are smithsonite, the zinc carbonate and hemimorphite, frequently referred to as …
A Study Of Mine Scraper Buckets And Their Efficiency, Austin Bond Clayton
A Study Of Mine Scraper Buckets And Their Efficiency, Austin Bond Clayton
Masters Theses
"The use of power drawn scrapers, often called "slushing", for the moving of ore, stops filling, and waste rock has become standard practice in many mining operations. Several types of scrapers have been developed by practical application or by trial and error methods. However, a direct comparison of these scraper types under identical conditions has not been noted in a review of literature on the subject of mechanical loading. Written inquiries to authorities on scraping practice have brought replies that no previous comparisons of scraper types on a modal scale have been attempted. Therefore, the following thesis problem was set …
A Comparative Analysis Of Some Recent Mining Practices In The Tri- State Mining District, James Francis Alexander Taylor
A Comparative Analysis Of Some Recent Mining Practices In The Tri- State Mining District, James Francis Alexander Taylor
Masters Theses
"The Tri-State District, encompassing contiguous corner portions of Southwest Missouri, Southeast Kansas, and Northeast Oklahoma, has been, for many years, the leading zinc producer of the United States. However, rising labor costs and decreasing grade of ore reserves have meant that many of the mines gradually have become marginal in the economic character of their operations. In an attempt to counteract these adverse effects, steps were taken to attain lower cost mining methods, and mechanization has been introduced over a period of years. Further, the research program of the Eagle-Picher Company, the leading producer of the district, has been accelerated …
A Study Of The Separation Of Feldspar From Missouri Granite, Vernon Louis Kasten
A Study Of The Separation Of Feldspar From Missouri Granite, Vernon Louis Kasten
Masters Theses
"The greatest use of feldspar is as a flux in the Ceramic Industry where it is used in the manufacture of abrasives, floor tile, terra cotta, china, and earthenware of all types. It is also used in the manufacture of glass and enamels, and much is used as grinding medium in powdered form because it is softer than the common abrasive, quartz...Missouri Granites are composed of feldspar, quartz, mica, and other materials, which may or may not occur in all the samples. It is the purpose of this investigation to attempt a separation of the feldspar from these other components …
The Development Of A Course Of Study In Consumer Science For The Senior High School Of Sturgis, Michigan, Harold R. Bowdish
The Development Of A Course Of Study In Consumer Science For The Senior High School Of Sturgis, Michigan, Harold R. Bowdish
Masters Theses
Chapter I
Introduction
Statement of the Problem. To introduce a phase of education designed to help every individual to live healthfully and comfortably, to buy goods and services wisely, and to obtain the greatest use of those goods and services is a tremendous undertaking. Science teachers are in an excellent position to contribute better understanding of the place of the consumer in our social system. It seems logical that a textbook in this field cannot be written which will serve every community with the same degree of effectiveness because the texts are written by authors who are interested in establishing …
The Analysis, Evaluation, And Selection Of American History Textbooks For Senior High School Classroom Use, Fred A. Weiss
The Analysis, Evaluation, And Selection Of American History Textbooks For Senior High School Classroom Use, Fred A. Weiss
Masters Theses
Chapter I
The Purpose and Procedure of this Study
Introduction
American history has long held a well-established place in the curriculum of the senior high schools of the United States. In many schools every pupil is required to take American history in order to be eligible to graduate from high school. If American history is not included as a specific subject offered in the curriculum of a senior high school, then one may expect to find it incorporated into some other part of the curriculum, perhaps into a general social studies course.
A Study Of Methods For The Purification And The Removal Of Color From Trinitrotoluene Wash Waters, William Wilson
A Study Of Methods For The Purification And The Removal Of Color From Trinitrotoluene Wash Waters, William Wilson
Masters Theses
"Symmetrical Trinitrotoluene is stable in the presence of moisture, but the nonsymmetrical trinitrotoluenes permit replacement of a nitro group with the formation of a nitrated cresol and nitrous acid. Nitrated cresols form salts similar to the picrates. To avoid these nonsymmetrical trinitrotoluenes the Ordinance Department, U. S. A., requires that Grade I trinitrotoluene have a solidification point of at least 80.2⁰C.². Numerous methods for purifying the crude trinitrotoluene and others for separating the nitrotoluenes have been suggested"--Introduction, page 1.
A Study Of The Electrolytic Reduction Of Pyrrole, Don Richard Strehlau
A Study Of The Electrolytic Reduction Of Pyrrole, Don Richard Strehlau
Masters Theses
"A review of the chemical literature has shown that electro-organic methods compare favorably with purely chemical methods for certain syntheses belonging to the following general classes of reactions: coupling, oxidation, reactions with halogens, and reductions. Electro-organic methods have been used most successfully in synthesis by reduction. The chief advantage is using electrolytic reduction in preference to a chemical one is that it offers a more exact control of conditions, and consequently should give a higher yield and a purer product. The advantages of the means of reduction suggested an investigation of its use in the synthesis of hydrogenated products of …
A High Alumina Concentrate From Low-Grade Burley Clay, Leonard Stearns
A High Alumina Concentrate From Low-Grade Burley Clay, Leonard Stearns
Masters Theses
"The principal source of raw material for the production of high-alumina refractories are the diaspore clays of Missouri. These highly refractory clays contain a large percentage of the mineral, diaspore, a monohydrate of alumina whose theoretical chemical formula is Al₂O₃ʺH₂O. The clays as mined contain from 85 to 65 per cent alumina...Diaspore clays as now found fill sandstone-lined "sink holes" or depressions in the parts of the district underlain by rocks of the Pennsylvanian Age. They are rough open-textured clays, grey or buff in color usually, containing the mineral diaspore in the form of shot-like particles or "oolites." There are …
Recovery Of Manganese From Oxidized Ores As Iron-And Phosphorus-Free Soluble Salts, Emil Pietz
Recovery Of Manganese From Oxidized Ores As Iron-And Phosphorus-Free Soluble Salts, Emil Pietz
Masters Theses
"There is a great demand at present for this country to develop its manganese resources. The hazards encountered because of the present international crisis make it almost impossible to import high-grade ores. Manganese is one of the most important strategic metals because it is vital to the production of steel. After the stock piles are depleted and the imports decreased, the deficit must be supplied by the domestic deposits. A great deal of research has been done to concentrate the domestic low-grade ores but new problems have always been encountered. The differences in the properties of the low-grade ores from …
Determination Of Alkalies In Portland Cement By The Dropping Mercury Electrode Method, William Joseph Smothers
Determination Of Alkalies In Portland Cement By The Dropping Mercury Electrode Method, William Joseph Smothers
Masters Theses
"In many industries whose product or products contain alkalies, the determination of the amount present is very essential from a control standpoint. This present investigation is concerned with a method for quantitative determination of sodium and potassium as accurately as by customary chemical methods and which will require less time in its operation. Portland cement is a product in which the amount of sodium and potassium present is of prime importance. This importance of the alkalies upon the behavior of concrete was first noticed in California where, after numerous tests, it was definitely shown that with certain aggregates there was …
A Study Of Former Students Of Maher’S Business College, Merlin J. Claucherty
A Study Of Former Students Of Maher’S Business College, Merlin J. Claucherty
Masters Theses
Chapter I
The Value of Follow-Up of Teaching and Guidance in Business Colleges
Introduction
It is the constant desire of every business college to keep up-to-date with that which is current in business procedure and education. A number of investigation have been made by placement offices, research bureaus, and training institutions for the purpose of assisting young people to become better adjusted to the community and to determine the supply and demand of employment in the different occupations.
A Study Of Base Exchange And Attendant Disintegration In Carthage Marble, Elmond Lowell Claridge
A Study Of Base Exchange And Attendant Disintegration In Carthage Marble, Elmond Lowell Claridge
Masters Theses
"The purpose of this investigation was to study the base exchange reaction occurring in Carthage marble as a possible cause of unusually rapid disintegration of Carthage marble which has been widely observed in various localities and under certain conditions. If this were found to be the principal cause of such disintegration the groundwork would be laid for research on a means of preventing it. According to Mr. R. E. Mayes, president of the Carthage Marble Corporation, forty to fifty percent of the stone quarried by this company is discarded because of large stylolitic veins. This represents a loss of many …
Manufacture Of Salt Cake By The Hargraeves Process, Philip Hall Delano
Manufacture Of Salt Cake By The Hargraeves Process, Philip Hall Delano
Masters Theses
"The Hargraeves process of manufacturing salt cake has not lived up to the great expectations that were held for the process at the time of its development...The inventors, Hargreaves and Robinson, do not pretend to have been the first to make salt cake by the action of sulfur dioxide upon common salt in the presence of air and steam; they claim only to have made the process practicable by a large number of patents. Numerous earlier patents for this reaction were taken out by others but none of these former proposals was successful; it was the details of the process …
Electrodeposition Of Copper-Lead Alloys From A 7.2 Per Cent Amine Solution Saturated With Respect To Copper And Lead. Study Of The Production Of Cupric Oxide To Be Used As Solute, Edmund Simon Roszkowski
Electrodeposition Of Copper-Lead Alloys From A 7.2 Per Cent Amine Solution Saturated With Respect To Copper And Lead. Study Of The Production Of Cupric Oxide To Be Used As Solute, Edmund Simon Roszkowski
Masters Theses
"The purpose of this work is to deposit electrolytically a copper-lead alloy from an amine solution for use specifically as a bearing metal. Generally speaking there are four classes of bearing metals: tin base alloys or the babbitts; the cadmium base alloys or the white metals; the silver alloys; and the copper-lead alloys. Additions of other metals may be employed to produce alloys with certain desirable properties"--Introduction, page 1.
Studies On The Quantitative Analysis Of Rhenium And Its Occurrence In The Products Of Molybdenite Processing, Walter Keith Dean
Studies On The Quantitative Analysis Of Rhenium And Its Occurrence In The Products Of Molybdenite Processing, Walter Keith Dean
Masters Theses
"There is at the present time no commercially developed source of the metal rhenium in the United States. Since this metal is known to exist in molybdenite, it was felt that a study of the products of the metallurgical processing of this mineral might reveal a source of rhenium that could e developed. The Climax Molybdenum Co. provided a number of samples from their smelter at Langloth, Pennsylvania. Although an improved method for the quantitative estimation of rhenium was recently published, its accuracy was not high and the procedure exacting and time-consuming. These combined factors led to the selection of …
The Mineral Association In Manganese Ores, With Particular Reference To The Phosphorus-Bearing Minerals And Their Removal By Leaching Methods, Daniel Chalmers Mclean
The Mineral Association In Manganese Ores, With Particular Reference To The Phosphorus-Bearing Minerals And Their Removal By Leaching Methods, Daniel Chalmers Mclean
Masters Theses
"The United States Bureau of Mines Experimental Station at Rolla has recently been conducting an intensive investigation of the amenability of Arkansas red ores to enrichment by standard ore dressing methods. These Arkansas ores are low grade with the estimated reserves running into several million tons. They can be concentrated to meet all Grade B ferromanganese specifications - with the exception of that of the phosphorus content, but in all cases the phosphorus is so high as to make the ore worthless under present conditions. This condition suggested the problem of trying to discover a method by which the phosphorus …
Conodonts From The Marathon Basin, Brewster County, Texas, Roy William Graves Jr.
Conodonts From The Marathon Basin, Brewster County, Texas, Roy William Graves Jr.
Masters Theses
"Conodonts were discovered in the limestones of the Marathon region in the Big Bend country, Brewster County, Texas, as a result of field work during the summer of 1939. This was not the first known occurrence of these fossils from this region, however, as King earlier mentioned the occurrence of conodonts in siliceous shales of Devonian age. The discovery of conodonts in the Ordovician and Pennsylvanian limestones of the area had its inception in the attempt to determine whether the Dimple limestone (lower Pennsylvanian) or Maravillas limestone (upper Ordovician) was involved in a fault that was being mapped. These limestones …
The Effect Of Addition Agents In Grinding Portland Cement Clinker, Eugene Farrell Hill
The Effect Of Addition Agents In Grinding Portland Cement Clinker, Eugene Farrell Hill
Masters Theses
"In the dry grinding of most materials in a ball mill or similar apparatus, a degree of fineness is eventually reached when a noticeable decrease in the efficiency of grinding occurs. The degree of fineness where this phenomenon occurs, as measured by the specific surface of the material being ground, varies greatly with different materials. The accompanying effect in all cases, however, is the formation of a coating upon the balls; this coating in the case of cement adheres tightly to the balls and increases in thickness as grinding progresses after the initial "coating' fineness has been reached. Usually an …
Consumption And Uses Of Crude Barite And Its Derivatives, Peter Simonds
Consumption And Uses Of Crude Barite And Its Derivatives, Peter Simonds
Masters Theses
"Barite is a widely distributed mineral composed of barium sulphate - BaSO₄. Its most striking feature is its weight - its specific gravity of 4.5 being about twice that of salt and many other of the colorless, transparent and vitreous minerals of its general appearance. The Mineral is usually found in a state of considerable chemical purity. However, small amounts of strontium and calcium sulphates may isomorphously replace the barium salt. Crystals of barytes are orthorhombic; usually very perfectly developed and have a wide variety of forms. The simplest crystals are rhomb-shaped tables bounded by two faces of a basal …
Electrolytic Reduction Of Galena In Fused Salt, Peter Simonds
Electrolytic Reduction Of Galena In Fused Salt, Peter Simonds
Masters Theses
"A demand has long existed for a method of directly recovering elemental Sulphur, in addition to the Lead, from Galena ore. At the present time, the sulphur of this ore is dissipated in the lead blast furnace as sulphur dioxide fumes. While the fumes are trapped to avoid damage to the vegetation of the surrounding countryside, their concentration is usually too low to make sulphuric acid as a profitable by-product. Thus, contrary to some speculation, the sulphuric acid produces under the circumstances is usually not a true by-product in the money-making sense of the term in many cases, but a …
Photoelastic Investigation Of Short Beams, Ross R. Carrolla
Photoelastic Investigation Of Short Beams, Ross R. Carrolla
Masters Theses
"In this investigation the author used beams made of Bakelite. They were of rectangular cross-section and centrally loaded. These beams were viewed in polarized light and the maximum fiber stresses observed in that manner were compared with those computed from the flexure formula. The purpose was to determine the minimum length-depth ratio for which the latter gave fairly accurate results"--Preface, page 6.
Constitution And Properties Of Manganese-Copper Alloys, James Harrison Jacobs
Constitution And Properties Of Manganese-Copper Alloys, James Harrison Jacobs
Masters Theses
"This work was undertaken because of the recently revived interest in the use of manganese as an alloying element. This revival of interest has been mainly due to the development of the process for electro-deposition of manganese by the U. S. Bureau of Mines. Prior to the work of the bureau of Mines there was no commercial source of high purity manganese. Manganese made by the electrolytic process contains less than .03% impurities, while manganese made by other methods contains as high as 3% impurities. The use of high purity manganese as a base for alloys should open up an …
The Volumetric Determination Of Alumina In Clays And Related Materials, David Ferdinand Boltz
The Volumetric Determination Of Alumina In Clays And Related Materials, David Ferdinand Boltz
Masters Theses
"The primary purpose of this thesis was to develop a direct method for the determination of alumina in certain silicates. The classical gravimetric procedure for the analysis of alumina in clays and related materials has often been regarded as being too lengthy and troublesome, especially when only the percentage of alumina was desired. The correct determination of alumina is undoubtedly one of the most unsatisfactory of the chemical constituents of siliceous materials, and therefore the development of a direct volumetric method for the determination of this constituent was made the main objective of this research, page [1].
Absorption Of Carbon Dioxide In A Bubble Plate Tower, William Arthur Enderson
Absorption Of Carbon Dioxide In A Bubble Plate Tower, William Arthur Enderson
Masters Theses
"Gas absorption, one of the chief operations of chemical engineering, has occupied investigators for a long time. Results of many experiments on the general subject of gas absorption has been published. However, relatively few data have appeared in the literature on the use of bubble cap towers for gas absorption although they constitute one of the three major classifications of absorption equipment. Bubble cap towers are used extensively in the petroleum industry. More performance data would increase the versatility of existing equipment"--Introduction, page 1.
The Reactions Of Acid Halides With Sodium, Magnesium, Zinc And Amalgams, William H. Webb
The Reactions Of Acid Halides With Sodium, Magnesium, Zinc And Amalgams, William H. Webb
Masters Theses
"The reactions of acid halides with metals are of interest because there seems to be a possibility of abstracting the halogens from two molecules of the halide, and thereby bringing about a coupling reaction; or the formation of an intermediate organo-metallic compound which would react with another molecule of the acid halide. The result of these reactions should be the formation of diacetyl and acetyl chloride and of dibenzoyl or benzil from benzoyl chloride. This procedure would be far better than the usual procedures for the preparation of these compounds...The results reported in the literature by different workers, on the …
Coordination Of Transportation Systems Of The United States, Herman Blickensderfer
Coordination Of Transportation Systems Of The United States, Herman Blickensderfer
Masters Theses
"To any thinking man it must be apparent that the railroads are of vital necessity to the country at large as they can more cheaply move a host of the heavy commodities than can the trucks, and of course the waterways do not and cannot reach every part of the vast territory that must be served. On the other hand it is equally apparent that many of the other types of traffic can be handled more readily and cheaply by truck than by rail. This would lead one to conclude that some way should be found to give to each …
Design Study Of A Three Span Continuous Tied-Arch Bridge, George Perry Steen
Design Study Of A Three Span Continuous Tied-Arch Bridge, George Perry Steen
Masters Theses
"In this study of the continuous tied-arch bridge, having one main span and two equal side-spans, the following items are endeavored: (1) To set up the total internal work equations and to find the values of the unknown forces or redundants. (2) To compute to maximum moments for design and to complete the design of the super-structure for one bridge. Details, such as the gusset plates, rivets, connection angles, etc., are not designed; the effect of such being allowed in the design for dead load as a certain per cent for details. (3) To set up hypothetical conditions for other …
Petrographic Analyses Of The Chepultepec Sandstones Of The Norris Reservoir Region, Tennessee, Chilton Eaton Prouty
Petrographic Analyses Of The Chepultepec Sandstones Of The Norris Reservoir Region, Tennessee, Chilton Eaton Prouty
Masters Theses
"The Norris Reservoir is located in northeastern Tennessee, in the Appalachian Valley. It includes all or portions of Anderson, Campbell, Claiborne, Granger, Knox, and Union counties. The area is shown by the map of Pate I. It is approximately thirty-five miles long in a northeast-southwest direction and about eighteen to twenty miles wide, in a northwest-southeast direction. The area is bounded on the northwest by the Cumberland escarpment and on the southeast by Clinch Mountain. The other boundaries are arbitrarily drawn near the town of Clinton to the southwest and near Tazewell to the northeast"--Introduction. Location and Nature of the …