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Power Consumption In Horizontal Cylindrical Tanks, John J. Schlager Jan 1962

Power Consumption In Horizontal Cylindrical Tanks, John J. Schlager

Theses

The general correlation of Power Number vs. Reynolds Number for flat six blade turbines in a horizontal cylindrical tank without baffles has been determined. The correlation has been found to apply to this system and corresponds to the 4 - 10% baffle region in the vertical cylindrical tank as determined by Rushton, et. al. (1)

An important variable to be considered is the length of tank to impeller diameter ratio which was found to seriously affect the power consumption.

A power fall off was observed at high Reynolds Numbers and coincided with visual vortexing. This power fall off was found …


Fixation And Washing Techniques For Increasing Image Stability In Photographic Papers, Ray Eynard Jan 1962

Fixation And Washing Techniques For Increasing Image Stability In Photographic Papers, Ray Eynard

Theses

Not provided.


Dimensional Stability And Acutance : An Investigation Into The Dimensional Properties Of Various Aerial Films And A Study Of Their Acutance, Basilio J. Battaglia Jan 1962

Dimensional Stability And Acutance : An Investigation Into The Dimensional Properties Of Various Aerial Films And A Study Of Their Acutance, Basilio J. Battaglia

Theses

An experiment was run to determine if differences in drying temperature humidity conditions have any effect on the dimensional characteristics of five quite different aerial films used for various military applications. Acutance measurements were made from microdensitometer traces of each film-temperature and the data was statistically analysed.

Each sample was exposed through a precision stainless steel template to a density of about 1.0. Using an optical comparitor, the difference in size between the film and the template was measured to 10-4 inch. As the image is circular, the size in any direction can be found by mere rotation on …


Contrast Threshold For A Spot On A Photographic Print, Myron A. Berkovitz Jan 1962

Contrast Threshold For A Spot On A Photographic Print, Myron A. Berkovitz

Theses

A psychophysical investigation was carried out to determine the contrast threshold (represented by a density difference) for a spot on a photographic print with a uniform background density. Problems associated with determining a single value which is represenative of the existing density difference between the spot and surround, resulted from the inherent density variation of photographic print material. A series of eighty density difference measurements of the spot and immediatly adjacent surround are presented for prints which had 0, 50, and 100% frequencies of spot detection. A discussion concerning how the eye may be responding in this type of a …


Investigation Of Surficants On Gamma And Speed, Patrick De Marco Jan 1962

Investigation Of Surficants On Gamma And Speed, Patrick De Marco

Theses

The effects of Photoflo and Tween-20, two surficants were investigated on three different films. Gamma and speed were the criteria investigated. Photoflo was found to have generally little or no effect on the criteria investigated. Tween-20 was found to be effective in increasing the gamma and speed of the films tested. The relationship of gamma and speed change versus concentration level did not follow any recognizeable pattern.


Dye Sensitization Of A Photothermographic Emulsion, William Groves, Ronald Wichelman Jan 1962

Dye Sensitization Of A Photothermographic Emulsion, William Groves, Ronald Wichelman

Theses

The objective of this paper is to sensitometrically evaluate the effect of five sensitizing dyes (Acridine Orange, Pyronin E, Thionin, Erythrosin B, and Pinacyanol) on a photothermographic emulsion containing a 43-7-50 mole % ratio of mercurous oxalate, mercurous iodide, and silver iodide. The choice of dyes was based on their ability to sensitize into the longer wavelength region of the visible spectrum. Three concentrations of dye were used - 50, 100, & 200 micromoles per liter of emulsion. The sensitometric evaluation was based on the exposure of a neutral step wedge to tungsten light. The parameters investigated are those of …


Fugacity Coefficients Of Gases In Binary Mixtures, Louis David Mazzeii Jun 1961

Fugacity Coefficients Of Gases In Binary Mixtures, Louis David Mazzeii

Theses

A method of Pitzer for predicting component fugacity coefficients of gases in binary mixtures is evaluated by calculating 2100 fugacity coefficients and comparing the results to experimental data.

Pitzer employed the technique of Gamson and Watson in deriving an expression for fugacity coefficients. The expression is based on a three parameter corresponding states theory set of equations, and a definition of pseudo critical properties of mixtures, both previously proposed by Pitzer.

A further comparison with values calculated by similar methods of Edmister and Ruby, and Redlich et al (which previously were established as the most accurate general methods) indicates Pitzer's …


Thermodynamic Properties Of Hydrazine, Michael Perlswieg Jun 1961

Thermodynamic Properties Of Hydrazine, Michael Perlswieg

Theses

The thermodynamic properties of hydrazine have been evaluated for the saturated region and for the superheated vapor. The superheated vapor properties were determined for temperatures up to 2200°F and pressures to 3000 psia. Enthalpy, entropy, and specific volume are reported for the saturated vapor and liquid and the superheated vapor. Results are reported in the form of tables.

Enthalpy values are relative to the saturated liquid at 32°F. Entropy values are absolute. The thermodynamic properties have been based on experimental data where possible. Due to the lack of experimental pressure-volume-temperature data, however, the generalized correlations of Lydersen, Greenkorn, and Hougen …


Viscosity Correlations Of Saturated Fatty Acids And Their Esters, Thomas Joseph Redling Jun 1961

Viscosity Correlations Of Saturated Fatty Acids And Their Esters, Thomas Joseph Redling

Theses

Several correlations have been developed which permit calculation of the viscosities of the n-paraffin fatty acids and esters, beginning with formic and including stearic acid.

The correlations were obtained by interrelating the Log u and the Log Pv at the same temperature, where u is the viscosity in centipoise and Pv is the vapor pressure in millimeters Hg. A single line relationship represents all the fatty acids from propionic acid to and including stearic acid, while formic acid and acetic acid each have their own line. Methyl, ethyl, propyl and butyl formate can be represented by a single …


The Electrolytic Oxidation Of Para-Nitrotoluene, Mustafa Darwish Shamy Jun 1961

The Electrolytic Oxidation Of Para-Nitrotoluene, Mustafa Darwish Shamy

Theses

The factors affecting the electrolytic oxidation of p-nitrotoluene to p-nitrobenzoic acid have been studied, and optimum conditions determined for obtaining the best overall yield of 65.7 per cent. These Anode:lead sheetCathode:lead sheetAnolyte:250 cc of 50 per cent sulfuric acid
10 grams of p-nitrotoluene
5 grams of chromic trioxideCatholyte:250 cc of 50 per cent sulfuric acidVoltage:4.5 ± .5 voltsCurrent density:3.0 amperes per square decimeter.Temperatures65 ± 3°CReaction time:fifty per cent of the theoretical time required

It was observed that high potentials and prolonged reaction periods are detrimental to the yield.

A mechanism for the electrolytic oxidation process is suggested, based on experimental …


The Kinetics Of Hydrogen Reduction Of Chromic Oxide, Kurt Strater Jun 1961

The Kinetics Of Hydrogen Reduction Of Chromic Oxide, Kurt Strater

Theses

The hydrogen reduction of Cr2O3 to chromium metal was found to be feasible at very low water vapor concentrations, approximately -38° to -24°C, over a temperature range of 1130° to 1490°C. Hydrogen reduction under these conditions was predicted by the calculated equilibrium curves which also indicated that Cr2O3 is reduced directly to chromium without forming the intermediate oxide, CrO. This reduction path was confirmed by X-ray diffraction analysis.

The percent reduction of Cr2O3 at each reaction temperature was constant with time suggesting an inhibiting effect of the gaseous reaction product, water …


Attrition In A Fluidized Bed, Andrew Joseph Welter Jun 1961

Attrition In A Fluidized Bed, Andrew Joseph Welter

Theses

The object of this thesis is to study attrition in a fluidized bed in an attempt to find a reliable method for predicting attrition rate when fluid flow rates and particle sizes are varied.

The system studied consisted of air as the fluidizing median with bauxite and fuller's earth as the solids in suspension. Fluid flow rates were changed while all other variables were held constant. Systems with both large and small particles were studied for each material.

It was found that the attrition rate of the material when the bed is maintained at a constant mass flow rate is …


Investigation Of The Stability And Response Of A Reboiler Under Condensate Control, Francis Arthur Winter Jun 1961

Investigation Of The Stability And Response Of A Reboiler Under Condensate Control, Francis Arthur Winter

Theses

Control of heat flux by condensate throttling was investigated theoretically by frequency response analysis and experimentally on a simulated reboiler control system.

Transfer functions were derived for each component and ware used to describe the response of the experi- mental system. Experimental controller settings were in reasonable agreement with the calculated results. However, general overall control was poor because of dead time and cyclic disturbances. Experiments showed that the process contained dead time in the order of three to seven times the ultimate period (0.5 - 1.0 minutes). Several sources of disturbances prevented an accurate evaluation of stability at low …


Effect Of Elevated Temperature On Efficiency Of Corrosion Inhibitors, Walter Dzingala Jun 1961

Effect Of Elevated Temperature On Efficiency Of Corrosion Inhibitors, Walter Dzingala

Theses

An experimental program was set up to investigate the effect of temperature on the protection efficiency of various inhibitors of metal corrosion. Contrary to most studies, an appreciable amount of the work was done with the corrosive effect being determined on the metal specimens that were exposed first to the inhibitor, then to air at different temperature, and finally to the corrosive medium with no inhibitor present. The purpose being to determine whether the inhibitor treatment would provide a permanent protection for a metal surface or would it be necessary to furnish a continuous supply of the inhibitor to the …


Physical And Electrical Properties Of The Manganin-Type Alloys, Wallace William Macintosh Jun 1961

Physical And Electrical Properties Of The Manganin-Type Alloys, Wallace William Macintosh

Theses

This thesis is a report on the physical and electrical properties of the manganin-type alloys as compiled from the published literature on the subject. The peculiarities of these alloys, as related to mechanical history, heat treatment, and composition, are discussed. Empirical formulae, by which the temperature coefficient of resistance, the temperature of maximum resistance, the temperature-resistance equation, and the thermoelectric emf of these alloys against copper may be calculated, are shown.

A comparison of the effect of elongation on the specific resistivity of several sizes of manganin wire is made on the basis of experimental results. The effect of impurities …


Electrolytic Amalgam Reduction Of Cinnamic Acid, Alan Ira Mytelka Jun 1961

Electrolytic Amalgam Reduction Of Cinnamic Acid, Alan Ira Mytelka

Theses

The use of sodium amalgam and potassium amalgam to reduce cinnamic acid to hydrocinnamic acid was accomplished in two concentrically constructed cylindrical cells.

In the outer cell, liquid amalgam was prepared electrolytically using a mercury cathode. The amalgam was moved by a rocking motion into the inner cell where the cinnamic acid dissolved in ethanol was reduced to hydrocinnamic acid. The actual percent conversion as measured by iodine numbers varied from 6.0% to 567, the percentage depending upon the number of coulombs passed into the electrolytic cell, the amalgam used, and whether or not stirring in the inner reduction cell …


Thermodynamic Properties Of Formaldehyde, Raymond H. Koo May 1961

Thermodynamic Properties Of Formaldehyde, Raymond H. Koo

Theses

The thermodynamic properties of saturated and superheated formaldehyde were evaluated at ten degree temperature intervals from -19°C. to 400°C. and at various pressures up to 150 atmospheres.

Lydersen's correlations were used to estimate the critical constants.

Vapor pressure data were calculated using Riedel's method.

The generalized thermodynamic correlations of Hougen, Lydersen,'and Greenkorn were employed to obtain values of the thermodynamic properties in the saturated and superheated regions.

The values for temperature, pressure, specific volume, enthalpy, and entropy for saturated and super-heated formaldehyde are presented in the form of tables and graphs.


Limitations On Expression Involved In The Materials And Certain Techniques Of Ceramic Sculpture, Peter B. Riley May 1961

Limitations On Expression Involved In The Materials And Certain Techniques Of Ceramic Sculpture, Peter B. Riley

Theses

None provided.


Structure, Wood, And The Form Of Furniture, William Keyser May 1961

Structure, Wood, And The Form Of Furniture, William Keyser

Theses

None provided.


An Investigation Into Halftone Density Variation With Pre-Screened Graphic Emulsions, Robert Chaffee May 1961

An Investigation Into Halftone Density Variation With Pre-Screened Graphic Emulsions, Robert Chaffee

Theses

Information relating to the variation that can be expected in utilizing Graphic Arts emulsions has been of some interest in the past several years. A test was formulated utilizing a Pre-screened graphic emulsion and was conducted each day for a period of two weeks. Test results indicate that the density level is of definate significance. The variability that can be expected at higher levels of density is outside the relm of desired conformance.


A Study Of The Possibilities Of Developing Practical Ceramic Ware For Charcoal Cooking, John J. Masson Jan 1961

A Study Of The Possibilities Of Developing Practical Ceramic Ware For Charcoal Cooking, John J. Masson

Theses

Not provided.


Ceramic Murals, Candeger Furtun Jan 1961

Ceramic Murals, Candeger Furtun

Theses

In my Thesis I propose to study the Ceramic Murals at its beginning and at the present Age. Since it is a very wide and long topic to be handled by one person within a limited time, I shall confine myself to the first attempts of Mankind in the making of Murals in clay in Prehistoric times, in Mesopotamia and murals that are done very recently , mainly in the United States.


Hiding Power Of White Pigments : Theory And Measurement, Parker Bovaird Mitton, Lawrence Vejnoska Dec 1960

Hiding Power Of White Pigments : Theory And Measurement, Parker Bovaird Mitton, Lawrence Vejnoska

Theses

Optical properties of pigmented films such as hiding power, scattering coefficient, and absorption coefficient were measured at three bands of wavelength of light (blue, green, red) for ten white pigments at seven pigment concentrations in a paint. These pigments range from the highest index of refraction (rutile) to the very low index of an extender pigment (CaC031); they range from a fine particle size (average 0.2 microns) to a relatively coarse size (average 2.2 microns).

Among the findings presented below the first two confirm the general observations of pigment behavior found by others; the rest of the findings are new. …


Prediction Of Binary-Liquid System Viscosity From Vapor-Liquid Equilibria Data, Eugene Henry Okrent Sep 1960

Prediction Of Binary-Liquid System Viscosity From Vapor-Liquid Equilibria Data, Eugene Henry Okrent

Theses

This paper reviews the proposed methods for prediction of binary mixture viscosity. A calculation method is developed which predicts the binary liquid mixture viscosity of non-ideal systems of organic materials. The calculation method is an extension of the statistical mechanically derived equation:

ηm = Nh/V exp[χ1ΔG1++ + χ2ΔG2++ -ΔG?/κ vap]/RT

A method has been developed for establishing the value of (ΔGE/RT)vap from the constants of the Margules equation, which is an improvement over previous methods. The proposed equation is:

Log ηm = χ1 log η …


Correlation Of Pressure Drop And Holdup In A Packed Distillation Column, Nello Del Gobbo Jun 1960

Correlation Of Pressure Drop And Holdup In A Packed Distillation Column, Nello Del Gobbo

Theses

Reed and Fenske have proposed a relationship that correlates the variables of packing dimensions, operating conditions, and fluid properties involved in countercurrent flow through packed distillation columns. Pressure drop and holdup data, obtained by atmosphere is distillation in columns packed with wire helices, was applied to the correlation by Reed and Fenske with good results. At reduced pressures limited data indicated the possibility of variations in the correlation as a function of the molecular weight of the material distilled.

Cummins investigated the effect of reduced pressure and holdup in distillation for several liquids using protruded packing. An attempt to correlate …


Heat Transfer Coefficients In Nucleate Boiling, Gerald Burt Fefferman Jun 1960

Heat Transfer Coefficients In Nucleate Boiling, Gerald Burt Fefferman

Theses

The purpose of this study was to investigate some new approaches to the problem of correlating heat transfer coefficients in nucleate boiling, A survey of previous work done in this field reveals much inconsistency in recorded data relating the heat transfer coefficient to other properties of the observed system, but general agreement has been reached, however, concerning the important influence of the temperature difference between the heating element surface and the boiling liquid. As this temperature difference is increased, the surface coefficient of heat transfer rises until a critical point is reached, marking the end of nucleate boiling and the …


Equilibrium And Reaction Rate Constants Of Esterification Of Nitrobenzoic Acids, John Nicholas Korzun Jun 1960

Equilibrium And Reaction Rate Constants Of Esterification Of Nitrobenzoic Acids, John Nicholas Korzun

Theses

A determination of equilibrium constants and reaction kinetics for the esterification of ortho, meta, and para-nitrobenzoic acids with methanol and ethanol was performed. A search of past literature showed that the equilibrium constants for the above acids and alcohols had not been measured previously.

The equilibrium constants (Ke) obtained for ortho, meta, and para-nitrobenzoic acids using p-toluene sulfonic acid as catalyst and ethanol as the alcohol were 3.59, 4.56, and 2.91: respectively. Using methanol as the alcohol, the corresponding constants were 2.61: 2.65, and 1.92.

Hydrochloric acid was also studied as a reaction catalyst, but, a side reaction between catalyst …


The Electrochemical Product Of Sodium Meta Periodate, John Joseph Mooney Jun 1960

The Electrochemical Product Of Sodium Meta Periodate, John Joseph Mooney

Theses

An investigation of an electrolytic cell utilizing a nickel anode in alkaline solution for the production of sodium meta periodate from sodium iodate was conducted. The problem was to find an improved method of producing the salts of periodic acid.

The test conditions of cell operation were varied, i. e., temperature, concentration, hydrogen ion concentration, current density and the physical dimensions of the electrolytic cell. The optimum conditions cell operation were found to be a temperature of 21°C, a concentration of 0.10 grams per milliliter of sodium iodate, a pH of 13, current density of between 32 and 42 milliamperes …


Fugacity Coefficients Of Gases In Binary Mixtures, David W. H. Roth Jun 1960

Fugacity Coefficients Of Gases In Binary Mixtures, David W. H. Roth

Theses

Fugacity coefficients of components in gaseous mixtures have been calculated by a method proposed by Joffe which is based on the use of generalized thermodynamic functions, and on Kay's rule for definition of the pseudocritical points of a gaseous mixture. The method should be applicable to compounds which can be correlated by the theory of corresponding states.

The method was tested by application to 255 experimental points comprised of four gaseous systems, and included Argon-Ethylene, Hydrogen - Nitrogen, Methane - Ethane, and Methane n Butane. Thermodynamic functions from two recent generalized correlations, that of Pitzer et al., and that of …


Particle-Liquid Flow In Vertical Tubes, Frederick John Rowe Jun 1960

Particle-Liquid Flow In Vertical Tubes, Frederick John Rowe

Theses

It was the purpose of this investigation to develop an experimental Procedure which would allow the prediction of the variation of fraction void with varying liquid and solid rates from a minimum number of experiments carried out in simple apparatus. This procedure should allow prediction for both smooth and rough particles, and should be valid for several different shapes. The data collected can be plotted on a single chart showing the relation between fraction void, solids throughput, and liquid throughput for all vertical particle fluid systems. Such a method was suggested by Mertes and Rhodes1 in their work developing a …