Engineering Commons^™

The Depression Of Quartz In Sulphide Flotation, William Mcminn Billinghurst

Masters Theses

"The flotation of sulphide minerals from siliceous and calcareous gangue minerals always gives a concentrate that is contaminated to a greater or lesser degree with the gangue minerals, even though the collectors used do not show any appreciable collecting properties for the gangue minerals when they are treated alone. In an effort to reduce the amount of undesirable gangue mineral floated with the concentrate it is the practice to add arbitrary amounts of various reagents such as quebracho, alkali hydroxides, carbonates, silicates, sulphides, phosphates, fluorides, and sulphuric acid which have been found to be advantageous. The mechanism of depression is …

The Relationship Between The Centrifuge Moisture Equivalent And The Vacuum Moisture Equivalent In Soils, Samuel Payton Halcomb

Masters Theses

"Soil is a material that has been formed through the influence of many different natural agencies. The engineer is not so much interested in how the soil was formed, but he does want to know the characteristics of the soil with respect to its use as a structural material. Therefore, the engineer is primarily interested in the physical properties of soils.

Much progress has been made during the past twenty five years in the study of Soil Mechanics, but even today there is a tendency among engineers to think of soil as just a mixture of clay, sand, silt and …

Problems In Theatre Lighting And Pre-Selective Elctronic Lighting Control, Hasan Orhan Aker

Masters Theses

"Until the recent years, because of the lack in technical know-how of play producers and on the other hand the limited knowledge of the engineers about stage technique, all the advantages provided by efficient stage lighting could not be exploited. Especially, the different problems encountered from the point of view of lighting control, could not be solved for a long time.

It has been proven from theatres built lately, that the stage lighting designs made without a thorough study of the various stage conditions and requirements lead to a tremendous increase in cost and also inefficient operation of the whole …

The Reactions Of The Sodium-, Potassium-, And The Lithium Tungsten Bronzes In The Solid State, Keki Khodadad Irani

Masters Theses

"The first part of this dissertation has the intention of determining whether MoO₃ forms solid solutions with Na-W bronze corresponding to the formula NaWO_3(1-x) (MoO₃)_x and whether the so-called “sodium-molybdenum bronze” exists.

The next part is concerned with the solubility of K-W bronze in Li-W bronze at high temperatures, in a vacuum, and the last part or this work has the intention of studying the solubility of K-W bronze in Na-W bronze at different temperatures.

The interest in this work is of a purely scientific nature rather than of academic interest"--Introduction, page 1.

Bauxite Versus Diaspore Clay In High Alumina (70%) Refractory Brick, Bhikhubhai Mahadeo Sedalia

Masters Theses

"The last twenty five years have seen a remarkable change in the character and types of refractories for furnace construction. Not much more than a few years ago, the production of refractories consisted almost solely of fireclay and silica shapes. A few high alumina bricks were made from Missouri diaspore clays or from bauxite and fire clays. At a later date, although little used, high alumina refractories were available which were made from alumina of a higher degree of purity, by the fusion process. Today refractories covering the entire range of composition from about 98% SiO₂ to 99 1/2% …

Highway Construction And Maintenance Equipment With Machine And Automotive Repair Shops For The Reconstruction Of The Highways Of The Iv Division, Ankara, Turkey, Steve Theodorides

Masters Theses

"With the rapid advancements being made in travel and communication facilities today, the world is steadily growing smaller and people in the far places of the world are no longer strangers.

There is no doubting the importance of tractors, dozers, scrapers, power shovels, graders, bituminus construction equipment, aggregate handling, etc., in the present-day world, in aiding the progress of civilization and bringing to all people the good things of life.

It must be remembered that money expended for highways is not wasted, and can be classified as an asset.

In substance, this is a general project for the reconstruction and …

The Design Of An Apparatus For The Study Of Fast And Slow Chemical Reactions Involving Gases And A Kinetic Investigation Of The Catalytic Decomposition Of Silver Oxide, Hilbert Walter Crocker

Masters Theses

"An outstanding chemical engineer has stated that chemical kinetics is at present in a state similar to that of thermodynamics thirty years ago. The current situation with respect to thermodynamics and chemical engineering appears to be that a fair number of engineers understand the theory and appreciate the practical value of thermodynamics but are frequently handicapped in its use by a lack of data. This is especially true where data on material at extreme temperatures and pressures are required as in nuclear energy and jet propulsion development. The current situation with respect to chemical kinetics and chemical engineering is that …

Increased Stripper Well Recovery By Means Of High Voltage Electrical Heating, John Curtin Schratwieser

Masters Theses

"The purpose of this work is to investigate the possibility of using high voltage electrical heating to obtain increased stripper well production.

A substantial portion of the oil produced in the United States is obtained from stripper wells. These wells reach their economic limit when they can no longer produce sufficient oil to justify the cost of operation. In the majority of cases, however, there is still a high percentage of oil in the sand. If a production stimulus of sufficient magnitude is introduced into the formation, oil, otherwise nonproducible, may be recovered. It is the writer’s thesis that high …

Series Capacitors, Emcet Bilgeer

Masters Theses

"Static capacitors as an element of transmission and distribution circuits first appeared in the form of shunt capacitors. These shunt capacitors were primarily used in power factor correction. They can be regarded as a load in the circuit which draws a loading current. This loading current fleeing through the reactive line produces a voltage rise, thus reducing the voltage drop between sending and receiving ends. This phenomenon helps the voltage control of the feeder as well as power factor correction. The disadvantage of the shunt capacitor is its inflexibility. The shunt capacitor is connected across the line; hence the voltage …

A Survey Of Single Ended Tuned Grid Tuned Plate Class C Power Amplifiers, Chandrakant D. Gandhi

Masters Theses

"The analysis of tuned grid-tuned plate Class C power amplifiers has been treated by many authors in many ways. The methods differ in accuracy and in time required to obtain the end results. A survey of most important of these methods was taken up by the author of this thesis with an aim towards studying their accuracies, advantages and disadvantages. A general survey of this type of analysis has not been found in the literature. In this survey only the most important phases of the tuned grid-tuned plate single ended Class C power amplifiers are discussed.

This survey has been …

Investigation Of Vacuum Tubes As Four Terminal Networks, Vasil Uzunoglu

Masters Theses

"This thesis was undertaken with the aim of consolidating the most important work that has been done in the field of equivalent vacuum tube circuits which has been found to be highly disassociated.

The author of this thesis feels that this thesis is the most complete consolidation of information on equivalent vacuum tube circuits"--Introduction, page 3.

Study Of Relay Behaviour Under System Oscillations And Out Of Step Conditions, Emil D. Grigoriadis

Masters Theses

"The recent developments in harnessing electrical power have opened a new field in the improvement and betterment of the existing types of relays and the development of new types. Thus about 1930 the manufacturers introduced the high speed circuit breaker with operating times of the order of 8 cycles and the engineers awoke to the possibilities of high speed or one-cycle relays.

Many developments took place since that time which gave us the improved forms of Instantaneous Overcurrent Protective schemes, the Distance Relay Protection, the Carrier Current Protection and many others. Later, because of the war time problems of increased …

Investigation Of The Fundamental Properties Of Rubber-Asphalt Mixtures, Yali Cevat Hasan

Masters Theses

"The writer of this thesis believes that the most important thing next to the original construction cost of a road, is the maintenance cost. It is apparent that the maintenance cost for any given road is directly proportional to the percentage of worn out sections in that road. It is believed that climatic conditions are the very first cause of road failures and that traffic on the road often has a secondary degree of importance in the causing of road surface failures….

It is obvious that extreme heat as well as extreme cold will ruin a road. A heavy traffic …

A Study Of Volatility And Desulfurization Of Titanium Disulfide, Sheng-Tai Shih

Masters Theses

"The application of high vacuum for the promotion of metallurgical reactions is a comparatively new development. During the war the need for high vacuum in producing magnesium by the Pidgeon Process and in certain phases of uranium purification led to the perfection of both equipment and technique for high vacuum operations. These developments helped open the way for the entirely new field of vacuum metallurgy.

The reduction of metal oxides in vacuum has been studied by Dr. Kroll and Dr. Schlechten. They have been able to reduce many metals from their oxides under reduced pressures using carbon as a reducing …

A Study Of Radio Frequency Converters And Mixers, James J. Skiles

Masters Theses

"This thesis will present a detailed discussion of the principles of frequency conversion and the problems attendant to the design of converter stages. The topic of harmonic conversion has been singled out for a more extended treatment than is now available in the literature. This topic is the subject of the experimental investigation portion of this thesis. Harmonic conversion has applications in U-H-F receivers as well as in "Double Superheterodyne Receivers".

The discussion given to the frequency converter in the first section of this thesis will be without regard to any applications. General theory will be stressed, and most of …

The Specific Radioactivity And Ratio Of Hafnium To Zirconium In Ores From Different Continents And The Preliminary Design Of A Process For Producing Hafnium, Arliss V. Martin

Masters Theses

"An investigation of the weight ratio of hafnium to zirconium in ores from widely separated regions of the world was undertaken to extend knowledge on this ratio obtained by modern means and to compare with the results of previous investigators. This type of information is of interest in geochemical considerations and the value of some similar information in the literature has been vitiated by the relatively recent finding that past methods of analysis are not satisfactory. The specific radioactivity of the original ores was determined in an attempt to check the proposition originated by Hevesy and apparently generally held by …

Economic Analysis Of Secondary Distribution Networks, Charles F. Cromer

Masters Theses

"In the early history of commercial electricity in heavy load density areas, the d.c. Edison Network was developed extensively. As far as reliability is concerned it is exceeded by no system. At the present time it has been developed to the extent of automatic and non-automatic converters, motor-generator sets, booster sets and storage battery reserve capacity.

This type of network is fed from several substations in the area at utilization voltage.

As load densities have increased, the large amounts of copper required, the cost of substation sites and large rotating conversion equipment have made the expansion of the d.c. Network …

Design Of A Steam Power Plant To Be Erected In Mudanya, Turkey, Vahram Ogretmenoglu

Masters Theses

"The power plant, the design of which is submitted herewith, is to be erected in Turkey, at the center of the town of Kestik, in the district of Mudanya along the shores of the Marmora Sea. Mudanya is the harbor of the state of Brusa, and like most of the big cities, it is entirely electrified. However, electrification in Turkey has begun in the late twenty's; consequently, it has not yet been possible to bring electricity to the numerous small towns and villages. Several big projects have been undertaken for purposes of rural electrification, one of them being the erection …

The Effect Of A Uniform Layer Of Insulation On The Temperature Amplitude In Periodic Heat Flow, Ralph E. Schowalter

Masters Theses

"The object of this thesis is to determine by analytical methods the temperature at any time within a homogeneous semi-infinite solid protected by a uniform layer of insulation, while its one and only one plane face is subjected to a periodically fluctuating temperature. The temperature at an infinite distance within the solid is to remain constant, and the heat flow in the other two directions is to be considered negligible.

Periodically fluctuating temperatures are frequent in both nature and engineering. The surface of the earth is subjected to temperature changes which are very nearly periodic, and these changes are made …

Relationship Of The Overall Transfer Coefficient To The Factor In Ammonia Absorption, Ivan Lee Gray

Masters Theses

"Gas absorption has an important role in chemical and allied industries. It is used to separate one of a group of constituents from a gas stream. Poisonous or obnoxious gases may be removed from the gaseous waste products of chemical plants by absorbing them in suitable solvents.

Many investigations have been carried out and references too numerous to list have appeared in the literature on the general subject of absorption.

In all of this work one of the usual methods of reporting results has been to express the capacity of a piece of absorption equipment as an overall capacity coefficient …

The Effect Of Inlet Air Temperature On The Efficiency Of A Spark Ignition Engine, John B. Toomey Jr.

Masters Theses

"The object of this thesis is to determine the effect of inlet air temperature on the efficiency of an internal combustion engine. In most text books the subject is dismissed with mentioning the negative effect of warm air on the maximum output of the engine. This fact is recognized but since most engines are run at maximum output only a small percentage of the time, it would be possible to control the air temperature as the situation demanded. With the assumption that cold air could be used when full power is desired, it was decided to determine the effect of …

Investigation To Improve Recovery Of Copper And Gold From A Refractory Ore, Raymond Franklin Cathcart

Masters Theses

"Results of tests presented in this paper indicate that the Santa Maria del Oro ores might be processed by a method which should yield a gold recovery of 96 to 98 percent and a copper recovery of about 78 percent, both figures subject to an increase with further work and study of the problem.

In the method of processing outlined in Figure IX, the ores, mixed as under present operating procedure, would be crushed to minus 20-mesh and roasted with ten pounds of sodium chloride per ton of feed in a multiple-hearth, down-draft roaster at temperatures varying to a maximum …

Photoelastic Investigation Of Filleted Corners In Square Apertures In Flat Plates Subjected To Tension, Raymond Huston Bever

Masters Theses

"During recent years many advances have been made in solving engineering problems by mathematical means. While this method of solving problems is invaluable to the engineer, there are times when a rigorous mathematical solution cannot be readily obtained, and the engineer must resort to other methods, some of which are approximate.

This paper attempts to show the application of photoelastic investigation to such a problem. The results of this problem are quantitative, but they show without any doubt that this method of investigation has considerably influenced the modern design of machine parts and helped in many cases to improve construction …

An Economy Study Of Vierendeel Trusses, Donald Lee Dean

Masters Theses

"Since the introduction of the pin connected steel truss in the United States in 1847 as a truss that could be actually designed, there has been very few basic changes in the truss as a structure. True, web members have been sloped or braced in many different ways to best adapt the truss for the structural materials being used, and over the protests of many , pin connections have almost wholly given way to riveted or arc welded connections, however, the basic idea of using all members as two force members has prevailed. Concern over the existence of bending stresses …

A Method Of Mining The Kumtepe Lignite Deposit Of Turkey, Hilmi Dokuzoglu

Masters Theses

"The Agacle lignite deposit, as a potential source of fuel, near Istanbul, Turkey has been used in this study to apply the principles of strip mining operations. The details of the deposit upon which this thesis is predicated will be presented later in this paper.

The fuel requirement of the city of Istanbul with a population of nearly a million is considerably greater then can easily be met. Some of the fuel needs are accommodated by electrical energy by producer gas, by bituminous coal brought from Zonguldak (about 200 miles from the city), by charcoal, and by fuel wood. During …

The Underground Electrocarbonization And Gasification Of Mineral Fuels, Erich Sarapuu

Doctoral Dissertations

"The development of underground gasification methods for recovering mineral fuels is comparatively recent and several methods have been evolved for treating the various source materials. The problem of recovering solid and liquid fuels by underground gasification in gaseous form was primarily approached by means of opening underground entries which created the required fire-drift for starting the gasification in place.

Increasing knowledge of the whole problem of gasification in situ led to the evolution of new improvements in the underground gasification technique and, in the course of progressive research the preparations required for starting the gasification were accomplished from the surface. …

Precise Lattice Parameter Determinations Of Diamond Silicon And Germanium By The Asymmetric Method, Esrefettin Zeki Aka

Doctoral Dissertations

"The construction of the apparatus for production of powder patterns at a definite temperature and the technique for evaluation of x-ray powder patterns by the asymmetric method are described in detail, and the mode of error elimination is discussed.

A new scanning device is designed for use in x-ray diffraction work.

A modified method is described for the determination of densities of solids, which eliminates some of the difficulties interfering with other similar methods thus far proposed. Formulae are derived for the calculation of density as well as for reduction of density at a desired temperature.

The following conclusion are …

An Experimental Evaluation Of Explosives In Blasting Limestone And Granite, Harve Preston Nelson

Doctoral Dissertations

"The purpose of this study was the evaluation of military and commercial explosives. A standardized index of effectiveness was used as the basis of comparison.

Testing was conducted at the Experimental Mine of Missouri School of Mines and Metallurgy at Rolla, Missouri, and at Graniteville, Missouri. At the school mine, 16 drift rounds, 8 slab rounds and 70 quarry tests were made in the dolomitic limestone. This rock, known locally as the Quarry Ledge of the Jefferson City formation, is of Ordovician Age"--Abstract, page ii.

Four Papers On The Performance Of Thin Walled Steel Structures, George Winter, Warner Lansing, R. B. Mccalley Jr.

CCFSS Library (1939 - present)

“The investigations reported in the four papers were carried out under the auspices of the Engineering Experiment Station of Cornell University, Dean S. C. Hollister, Director, and in the School of Civil Engineering, Professor W. L. Malcolm, deceased, and Professor N. A. Christensen, Directors.

They are part of, or related to, an extensive investigation of thin-walled steel structures sponsored jointly by the American Iron and Steel Institute and Cornell University, of which Professor George Winter, Head, Department of Structural Engineering, is in active charge. On the part of the Steel Institute the work is directed by the technical subcommittee of …

Field Resolution Tests With The Metrogon Lens, Robert Greig Livingston

Professional Degree Theses

"The first portion of this treatise is devoted to a compilation of general knowledge concerning photographic resolution testing - an explanation of certain optical terms; the drafting of resolution targets; methods for averaging resolution values, measured at various positions on the format, to obtain one over-all value for an exposure; and a description of the factors involved in conducting the photographic operations. In the second part of the paper, analyses of the results obtained from line-target resolutions are made with the purpose of determining those combinations of aperture, filter, and shutter speed which result in high photographic resolutions. This information …