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The Status Of Gas-Lubricated Bearings, Bhaskar Dattatraya Shiwalkar

Masters Theses

"The idea of gas-lubricated bearings was suggested as far back as 1854 by Hirn, but it is only very recently that they have aroused a great amount of interest. The interest is centered on the advantages of gas-bearings for the following major applications:

1. High temperature lubrication where ordinary liquid or grease lubrication fails.
2. Bearings operating in radio-active atmospheres where conventional lubrication may break down.
3. Applications sensitive to contamination where fouling from lubricating oil becomes serious.
4. Low-friction devices--an especially important advantage because of the trend to high speed machinery.
5. Applications where positional accuracies down to micro-inches are required.

As a result …

The Conducting Sheet Analogy For Laplace And Poisson Equations, Ronald Edward Volker

Masters Theses

"This investigation determined the accuracy to be expected with conducting sheet analogy solutions for Laplace and Poisson equations using simple and relatively inexpensive instrumentation. Several problems were solved experimentally and compared to known theoretical solutions to check variables in the technique and the accuracy of the experimental solution. It was found that if proper procedures are followed, solutions can be obtained rather rapidly and with an error of less than 5% which compares favorably with accuracy obtained by other investigators with more complex, precise equipment"--Abstract, page 2.

Imperfections In A Silicon Crystal Studied By The X-Ray And Density Method, Pierre Borgeaud

Masters Theses

"The study of imperfections in several crystals of silicon was conducted by the x-ray and density method"--Abstract, page 2.

The Determination Of The Heat Transfer Film Coefficients Of Internally Heated And Twisted Strips, Karpurapu Venkata Apparao

Masters Theses

"As the demand for power supply is increasing, the power from nuclear fission is assuming an important role in the field of power production. The enormous quantity of heat generated during the fission process can be utilized for the generation of power. To get maximum advantage out of the fission process, the fission material must be fabricated into a unit of proper shape to permit the control of the process and safe removal of heat generated. This unit, composed of fuel elements is known as the reactor core and is one of the major concerns in nuclear power development.

The …

An Experimental Study Of The Effects Of Additives On The Collapsibility Of Carbon Dioxode-Sodium Silicate Bonded Foundry Cores, Robert G. Liptai

Masters Theses

"Every foundry is searching for methods and tools to raise product quality and production while lowering cost. In early 1954 published articles on the new carbon dioxide-sodium silicate process of core hardening began to stir the imagination of most of the foundries throughout the United States, This process has probably claimed more space in the foundry journals than any other subject, hailed by some as a cure-all and dismissed by others as unsatisfactory.

The list of advantages of this process was impressive, but anyone associated with the process was confronted with daily problems that had to be solved regardless of …

Effects Of Co2 On The Strength Of Lime Treated Clay Soil, Tuncer Karakurt

Masters Theses

“A large number of the difficulties encountered in highway work are due to the variable nature of soils. In addition to its variable nature, soil is a difficult material to deal with because of the complexity of its physical and chemical properties. From prehistoric times the construction of a satisfactory foundation has been one of the greatest problems facing the engineer and builder. Even though the needs of scientific methods were necessary far earlier, the study of soils as a construction material was scientifically given attention to only during the last three decades. Soil science being so young there are …

Analysis And Simulation Of A Cross-Correlation Communication System, Dennis Jay Gooding

Masters Theses

"Statement of the problem. The purpose of this study was (1) to calculate the probability of error as a function of receiver input signal-to-noise ratio for a typical communication system employing cross-correlation detection; (2) to design and construct an experimental model of such a communication system for the purposes of demonstrating the operation of the system and verifying the theoretical calculations"--Introduction, page 1.

Electrical Model Investigations Using The Horizontal Profiling Technique, Alan H. Kwentus

Masters Theses

"Electrical exploration methods have been used for many years as a means of determining subsurface structures and in the search for mineral deposits. Vertical profiling techniques can be used to determine rather accurately the resistivity and thichness of horizontal or gently dipping beds for cases up to four layers. Mathematical calculations have been made for multiple layers and theoretical curves have been computed and published for four and more layers. The vertical profiling method is not particularly well suited to the problem of locating lateral changes in resistivity produced by such features as ore bodies, sinks and channels. These features …

The Separation And Microdetermination Of Cobalt In High Purity Nickel, John Richard Knapp Jr.

Masters Theses

"It has been found that many substances in an extremely pure form or containing certain trace impurities exhibit many unique physical and chemical properties. Investigators studying these properties have encountered many difficulties, especially in preparing the extremely pure substance and/or in accurately determining the quantity of impurities present. These problems arise chiefly from the very similar chemical properties of the constituents being separated and the possibility of contamination during the necessary processing of the substance for purification or analysis.

Trace analysis, therefore, has become very important in recent years. Where previously analyses based upon parts per hundred were adequate, now …

Critical Load For A Rectangular Plate Simply Supported On Three Edges, Built In On The Fourth Edge, And Compressed On Two Opposite Simply Supported Edges By A Load In The Plane Of The Plate, Bert Louis Smith

Masters Theses

"There are many engineering structures in which thin plates are used extensively, some examples of which can be found in ship and airplane structures, bridges, etc. The problem contained in this thesis is the analysis of a thin rectangular plate simply supported on three edges, built in on the fourth edge, and compressed on two opposite simply supported edges by a load in the plane or the plate. This problem becomes one of stability, and the object of the solution is to find the smallest load that will cause the plate to buckle"--Introduction, page vi.

The Effect Of Boundry Layer Control By Passing Fluid Through Transverse Slots On Heat Transfer From A Pipe, Perakatte Joseph George

Masters Theses

"The object of this work is an experimental investigation into the possibility of obtaining an increase in the forced convection heat transfer coefficient for a pipe by passing the fluid through narrow transverse slots cut in the pipe, and thereby altering the boundary layer pattern.

Since the greatest barrier to the flow of heat from a solid to liquid exists at the boundary layer, it can be expected that any device which will alter the boundary layer pattern will alter the heat transfer coefficient. When mass crosses a boundary layer in a direction perpendicular to the main motion of the …

Effect Of Leaching On The Strength Properties Of A Hydrated Lime-Cement Stabilized Soil., Yurdakul Osman Ulugonul

Masters Theses

"The stabilization of soil has been carried on since early historic times. The Romans used lime and volcanic ash as additives for this purpose. After the discovery of cement and its property of bonding soil particles it became one of the essential additives in the soil stabilization field. Many other kinds of additives have been developed and are being used today for soil stabilization.

A question that arises through the increasing use of stabilizers in soil is whether the changes that are effected are of a temporary or permanent nature. Changes may occur from the degradation of the stabilized soil …

A Thermodynamic Study Of The Germanium Sulphides, Satya Prakash Jain

Masters Theses

"The experimental determination of some of the thermodynamic properties of germanium sulphide phases was conducted by a hydrogen reduction technique. The equilibrium H₂S/H₂ ratios were determined as a function of temperature for the two phase equilibria GeS₂-GeS and GeS-Ge. A Tutwiler analysis technique was used to analyze the equilibrated gas mixture for hydrogen sulphide content.

A detailed description is given for the process and the apparatus used in performing the experiments for equilibration of H₂S/H₂ gas mixture. The methods used for the preparation of germanium sulphide phases are also discussed.

The investigation …

Coal Dust Explosions And Their Prevention, Surya Narayan Roychowdhury

Masters Theses

"The purpose of this study is to review the various causes of coal dust explosions and to summarize the preventive measures through which it may be possible to minimize the hazards of coal dust explosions. The properties of coal dust which have an important influence on its explosibility are: fineness, purity, percentage of volatile matter, dryness, age and degree of oxidation, lifting velocities and dispersability, and its static electrification.

Explosibility of coal dust has been studied in laboratories, in explosion galleries and in an experimental coal mine. The data and results obtained from the tests showed that finely pulverized coal …

A Thermodynamic Study Of Germanium Sulfides, Sham Lal Malhotra

Masters Theses

"The vapour pressure of germanium monosulfide (liquid) was determined by a boiling point method. An expression for the vapour pressure as a function of temperature was obtained and the heat of vapourization calculated. Using the heat of sublimation data obtained by other investigators, the heat of fusion was calculated.

The thermodynamic properties, change of standard free energy (Δ F°) heat content (Δ H°) and entropy (Δ S°); of germanium disulfide were determined by using an indirect method. The equilibrium H₂S/H₂O ratios are determined for the reaction:

GeS₂ (s) + 2H₂O(g) = GeO_{2 …}

Investigation Of Economic Design Procedure For A Rigid Frame, Richard S. Groner

Masters Theses

"This work presents an analysis of various arrangements of component parts of a rigid frame. From this analysis a procedure is indicated for a logical choice of member sizes for a first trial selection of a frame for given loading conditions. The first trial solution yields a frame which is in the range of an economical design"--Abstract, page 2.

Deflections Of Two-Way Slabs, Gerald C. Godzwon

Masters Theses

"A reinforced concrete member is by no means a truly elastic member, hence all ordinary deflection calculations relating to it, whichever method, are approximate. By the use of model study actual reinforced concrete slab models, of different end conditions, were built and tested for deflections under uniform loadings. Theoretical and actual deflection of reinforced concrete slabs are compared. The results of these tests indicate that the theoretical deflection equations may be 60 to 80 percent in error when applied to reinforced concrete slabs"--Abstract, page 2.

Heat Transfer Coefficients In Artificially Roughened Pipes, Mehmet Hayati Turan

Masters Theses

"The purpose of this investigation is to determine experimentally the effects of three different types of artificial roughness on the convective heat transfer coefficient in a pipe and compare these values with that for a smooth pipe for turbulent flow"--Introduction, page 7.

A Method Of Design For Spiral Reinforced, Eccentrically Loaded, Concrete Columns, Lloyd O. Senter

Masters Theses

"This thesis presents a method of designing spiral reinforced, eccentrically loaded, concrete columns on the basis of the 1957 American Association of State Highway Officials specifications.

Equations from AASHO, in conjunction with equations derived in this thesis, are programmed for and solved by the IBM 650 digital computer. The data obtained from the computer is plotted such that, given the normal load and moment on a column, the minimum required area or reinforcing steel may be read directly from the graph.

The derivation or equations, the computer program, and the graphs are included in the thesis"--Introduction, page 1.

Temperature Distribution In A Semi-Infinite Solid As A Function Of The Input Heat Flux, Lloyd Carl Laciny

Masters Theses

"In this thesis the problem of varying heat flux into a semi-infinite solid initially at zero temperature is investigated. Varying heat flux means that the heat transferred to the solid by its surroundings is a function of time; in this particular problem it is chosen to be an exponential function of time. A semi-infinite solid is one which is bounded by only one plane.

This subject has achieved considerable importance in the field of space technology. A body in space is beyond the realm of aerodynamic heating and non-uniform skin temperatures reached as a result of radiation from a high …

Heat Transfer In A Vortex Flow Metal To Air, Elisha Rachovitsky

Masters Theses

"In this study heat transfer in a vortex flow has been investigated experimentally and analyzed qualitatively.

Air was forced through a Ranque tube in order to get a swirling turbulent flow in its "hot" section. The test section, having a diameter of .355 inches and a length of 27.5 inches, was heated by an induction coil.

Three types of flow were under investigation: a linear turbulent flow, a vortex uniflow and a mixed vortex-linear turbulent flow.

The experiments covered a range of tube-wall temperature from 570 to 900 Deg. R and inlet pressure to the vortex generator ranged from 25 …

Methods For Calculating The Minimum Amortization Tonnage And Maximum Present Value For An Ore Body, Garrett M. Sainsbury

Masters Theses

"The discussion is divided into three parts. Part I describes a procedure for determining the mining rate that gives the minimum amortization tonnage required of an ore body, and the amount of that tonnage. The basic idea is that amortization tonnage is equivalent to the estimated capital costs, including interest, divided by the estimated operating profit per ton. Both capital costs and operating profit per ton can be expressed as functions of mining rate by making use of empirical equations. Therefore, amortization tonnage can be expressed as a function of mining rate. The amortization tonnage is calculated for a series …

High Temperature Oxidation Of Nickel, Virgil R. Friebel

Masters Theses

"Using a sensitive volumetric technique, a study was made of the kinetics of oxidation of nickel at 1200° C. and 1300° C. Three purities of nickel were used for the investigation which was limited to the initial three hours of reaction.

The rate of oxidation of nickel followed the parabolic rate law after an initial period of deviation which lasted up to 40 minutes. No direct correlation was found between the oxide thickness and the end of the period of deviation from the parabolic rate law.

The purity of the nickel was found to have a marked effect on the …

The Constitution Of Magnesium-Rich Magnesium-Zirconium Alloys, Kenneth Allen Fowler

Masters Theses

"The magnesium-zirconium system has been studied to 0.8 per cent zirconium which represents the limit of solubility of zirconium in liquid magnesium at 950°C. Alloys have been prepared by two methods of alloy additions, and the results compared. Microstructural studies have been made of the alloys in the cast, extruded, and heat-treated conditions. The limit of solid solubility has been determined on the basis of resistivity and temperature coefficient of resistivity measurements, as well as by metallographic examination, with good agreement. A secondary structure resulting from precipitation of a second phase within cored regions of the alloy has been studied …

The Dielectric Strength Of Some Anti-Corrosive Paints, John Harvey Gustafson

Masters Theses

"Metals undergo chemical reaction with nonmetallic elements of their surroundings to produce compounds which are either oxides or salts. These corrosion products, as they are called, may accelerate, impede, or have no influence on the course of further corrosion. It is unfortunate that iron, the metal of greatest use to man, receives very little protection from its corrosion products. There are no easy or inexpensive means of prevention of this corrosion and at best the reactions can only be controlled. One method of control is the use of anti-corrosive paints. Their protection is produced by placing an inert, continuous, and …

The Effect Of The Rare Earth Elements On The Hot Workability Of Ingot Iron, L. A. Neumeier

Masters Theses

"The effect of mischmetal and rare earth oxides on the hot workability of ingot iron in the hot-short region was studied. Thirteen heats were melted in air in a basic-lined induction furnace. All heats were thoroughly deoxidized with aluminum prior to the rare earth additions. Mischmetal was added in amounts of 0.1, 0.3 and 0.5 per cent. Rare earth oxides were added in amounts of 0.1 and 0.2 per cent. Temperatures were maintained at approximately 2900°F and holding intervals between mischmetal additions and pouring at two minutes. Bars were hot rolled and swaged for hot twisting in the hot-short region. …

Determination Of Vapor-Liquid Equilibrium Data By Continuous Distillation, David William Bunch

Masters Theses

"The procuring of experimental vapor-liquid equilibrium data has been a problem of considerable importance to chemical engineers for a number of years. Modern distillation theory and practice have made accurate vapor-liquid equilibrium data practically a necessity.

Using conventional methods for determining vapor-liquid equilibrium data, an experimenter can obtain only a single vapor-liquid equilibrium composition per trial. Ramalho working with Tiller has developed a new method which makes possible the determination of all values of the vapor and liquid concentrations in a single experiment.

The work done by Ramalho indicated that the necessity for very precise temperature measurements presented a serious …

Segregation Method As Possible Process To Beneficiate Oxidized Lead Ores, Jose Molfino Tomasio

Masters Theses

"In this investigation it has been demonstrated that the Segregation Process has merit for treating oxidized lead ores.

The process comprises heating the crushed ore with salt and coal at about 750° C. to produce metallic lead attached to the carbon particles, which then is recovered by conventional flotation methods.

The quantities of sodium chloride and coal required for the best segregation of lead obtained in this work was 1.0 percent of coal and 1.0 percent of salt by weight.

Good segregation was obtained by using salt and coal as fine as 65 or 48 mesh. Segregation varied with the …

An Experimental Investigation Of Receiver System Sensitivity, James Henry Johnson

Masters Theses

"A method of determining the minimum detectable power density incident at the receiving antenna of a UHF receiver is proposed. The minimum detectable power density is the power density required to produce a signal-to-noise ratio of unity in the output of the receiver. The proposed method includes the receiving antenna impedance, the necessary connecting transmission lines, and the receiver impedance.

It is shown that an error in the antenna directivity will produce a significant error in the overall sensitivity of a receiving system. Since the directivity is the most difficult system variable to determine experimentally, it is probably the limiting …

Physical Property Tests Of Rock, Centrifugal Tests And The Design Of Underground Mine Openings, Samuel Shu Mou Chan

Masters Theses

"Proper design of stable underground mine openings is important to the mining industry today. Various methods have been utilized by investigators to approach this goal.

A review of previous investigations of each of the phases of underground mine opening stress analysis is presented.

An approximate method of designing underground mine structures based on estimation of the initial stress field, rock physical property tests, and model tests, together with preliminary field data, is presented, and a specific example given"--Forward, page i.