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Articles 5941 - 5970 of 5972
Full-Text Articles in Entire DC Network
Ultraviolet Analysis Of Mixtures Of O-, P- And M-Nitrotoluene, John Thomas Dempsey
Ultraviolet Analysis Of Mixtures Of O-, P- And M-Nitrotoluene, John Thomas Dempsey
Theses
This paper presents a spectrophotometric method of analysis of mixtures of the isomers of pure nitrotoluene, which are free of the dinitro-compounds and other impurities. The analysis is made in the ultraviolet region with a Beckman DU Spectrophotometer. Graphical methods are developed for both binary and tertiary mixtures. The graphs, which form the basis of the method, represent the theoretical absorbancies for various mixtures of the isomers. From these graphs the concentrations in an unknown mixture can be read directly if the absorbancies, at specified wavelengths, are known.
This analytical method is based on the fact that the absorbancies of …
A Generalized Correlation For The Effect Of Pressure On The Difference In Heat Capacities Of Gases, Leon Bleich
A Generalized Correlation For The Effect Of Pressure On The Difference In Heat Capacities Of Gases, Leon Bleich
Theses
A generalized correlation is presented for the difference in heat capacities at constant pressure and constant volume, Cp-Cv, as a function of reduced pressure with parameters of reduced temperature. The correlation covers a pressure range of pr a 0.2 to pr = 15.0 and a temperature range of Tr = 1.0 to Tr = 5.5. The correla- tion was based on values of Cp-Cv calculated from the Benedict - Webb - Rubin Equation of State for five hydrocarbons, namely, methane, ethylene, ethane, propane, and n-butane.
The results show that Cp-Cv …
Ion Exchange Technology In The Sodium And Ferric Ion-Dowex 50 Systems, Alfred George Hoerrner
Ion Exchange Technology In The Sodium And Ferric Ion-Dowex 50 Systems, Alfred George Hoerrner
Theses
This investigation was directed toward the extension of data on the kinetics of monovalent - trivalent cation exchange and to establish data on the relationship between temperature and total capacity of an ion exchange resin. In order to compare the present study to a previous investigation by Klosowski (2), the capacity of the resin used for ferric and chromic ions was also measured.
In the kinetic study, the ferric ion-hydrogen ion exchange using Dowex 50 X-8 resin was studied in an agitated vessel. A two-bladed marine type propellor was used and the agitator speed was varied from 400 to 800 …
The Electrolytic Regeneration Of A Phenidone-Hydroquinone Developer, Howard Hall
The Electrolytic Regeneration Of A Phenidone-Hydroquinone Developer, Howard Hall
Theses
An attempt was made to regenerate a phenidone -hydroquinone developer. During the electrolysis the concentration of all the components remained constant with the exception of bromide, which was released as bromine from the anode. The possible use of the apparatus to remove bromide and reduce the replenishment rate in a continous processing system is suggested.
The Wars Of The Sioux, Dorothy Holland Adderhold
The Wars Of The Sioux, Dorothy Holland Adderhold
Theses
This paper examines the wars fought by Plains Indians for over forty years following the Civil War as they attempted to preserve their homeland and ancestral way of life.
A Shortened Type "C" Process (Characteristics Of A Combined Bleach-Fix), Donald Sykes
A Shortened Type "C" Process (Characteristics Of A Combined Bleach-Fix), Donald Sykes
Theses
The theory of combined bleach-fix bathes is discussed with an explanation of the function of sequestrene. Three investigations are described were the components of the solutions are varied, and the results stated. Formulas of successful bleach-fix baths used with a Kodak P122 Process are given.
Kinetics Of Chromium-Hydrogen Ion Exchange, Frank Joseph Klosowski, Alfred John Meinhardt
Kinetics Of Chromium-Hydrogen Ion Exchange, Frank Joseph Klosowski, Alfred John Meinhardt
Theses
In this investigation the rates of trivalent-univalent cation exchange in a stirred batch reactor for the chromic ion-Dovex 50 system have been measured. The progress of the reaction has been followed continuously by measuring the change in hydrogen ion concentration of the bulk solution as a function of time with a Beckman pH Meter having external electrodes immersed in the reaction mixture.
This work has been undertaken to determine the rate-controlling mechanism of the reaction, and the influence of agitator speed, particle size, and solution concentration on the rate of exchange. Agitator speed. studied, as limited by the equipment, are …
Equilibria In The Esterification Of Boric Acid, Richard William Palizay
Equilibria In The Esterification Of Boric Acid, Richard William Palizay
Theses
A solvent extraction method was developed to determine the equilibria in the esterification of boric acid, In this method boric acid was reacted with various alcohols. After equilibrium was reached, the ester was isolated from the reaction mixture by means of a solvent and the amount of ester determined quantitatively. The equilibrium constants were then calculated for the reaction of boric acid with several alcohols.
Zone Refining Of Anthracene, Charles Poultney Perot
Zone Refining Of Anthracene, Charles Poultney Perot
Theses
The process of zone refining involves the passage of a molten zone along a rod of solid. As the zone progresses, composition of the material freezing out generally differs from that melting, so solutes are redistributed. Enrichment of the major component occurs toward one end of the rod. (Usually the end of frozen.)
In the present work, impure anthracene was subjected to zone refining. Feed first run was C.P. anthracene with a known impurity of 2.0% phenanthrene. After two passes no phenanthren was detectable in the first layer frozen. (Analysis was by ultra-violet spectrophotometry.) Although the zones melted out were …
The Rates Of Hydrolysis Of Aryl Halides, Jack Robert Roeder
The Rates Of Hydrolysis Of Aryl Halides, Jack Robert Roeder
Theses
The object of this work was to determine the relative activity of the halogens, chlorine, bromine and iodine toward hydrolysis in a water-soluble aryl halide in which the halogen is activated by a nitrogroup in the orthoposition.
The order of activity was found to be C1) POI. In the case of the chlorine compound a run was also made on sodium 2-chloro-5-nitrobenzenesulfonate in which the nitro group is in a pare position with respect to the halogen.
The preparations of sodium or potassium 4-chloro-3-nitrobenzene sulfonate (I), sodium or potassium 4-bromo-3-nitrobenzene sulfonate (II), sodium or potassium 4-iodo-3-nitrobenzene sulfonate (III), and sodium …
Vapor-Liquid Equilibria, Vincent De Paul Brown
Vapor-Liquid Equilibria, Vincent De Paul Brown
Theses
The thesis was undertaken for the purpose of testing available experimental vapor-liquid equilibrium data for thermodynamic consistency, with a view to finding an intercorrelation of the activity coefficient-concentration curves, for different groups of systems, as a function of the intercepts. It was hoped that a correlation using molar volumes, parachor volumes, or molecular weights would be developed which could be explained on the basis of hydrogen bonding.
The Redlich and Kister1 equations were used to smooth the experimental data and to obtain values for the constants B, C and D. Redlich and Kister state that these constants serve as …
A Study In Diffusion, Nicholas James Driscoll
A Study In Diffusion, Nicholas James Driscoll
Theses
The object of this thesis was to build an experimental apparatus and to study the diffusion of crystal violet in ethanol-water mixtures and diacetone alcohol-water mixtures. In order to validate experimental technique and to check the work of Mouquin Cathcart(1) who postulated compouhd formation in ethanol-water based on diffusion studies, experiments were conducted on the ethanol-water system in the area where compound formation was predicted.
In order to check the proposal of Konrad(2), based on studies of the heats of mixing that compound formation occurs between diacetone alcohol and water, studies were made on the diffusion of crystal violet in …
Exchange Adsorption Of Electrolytes On Titanium Dioxide, Richard Algimantas Slepetys
Exchange Adsorption Of Electrolytes On Titanium Dioxide, Richard Algimantas Slepetys
Theses
During the manufacture of titanium dioxide pigments many processing steps are carried out in solutions of electrolytes. Adsorption of these electrolytes strongly affects properties of the finished pigments.
Adsorption of electrolytes Was studied on titania samples prepared by controlled neutralization of titanium tetrachloride solutions with ammonium hydroxide, and one sample of commercial sulfate process rutile titania. In analogy to zirconia--as reported by Kraus and Phillips?22,23 titania also behaved as a weak anion exchanger in acid solutions and as a weak cation exchanger in basic solutions. Acid or base liberated was approximately equivalent to ions exchanged. On the best sample …
Self-Heating Of Wood Fiber, Kenneth Norman Smith
Self-Heating Of Wood Fiber, Kenneth Norman Smith
Theses
An investigation was made to determine what portion of wood is responsible for the self-heating of wood fiber, where self-heating is defined as the increase in temperature of a material above the temperature of its surroundings due to an exothermic reaction occurring within the material. The phenomenon of self-heating of wood fiberboard has long been known, but very little has been done to discover the particular part of the wood which generates the heat.
Wood fiberboard was tested for self-heating by placing a. cubical sample in a specially constructed furnace and heating it to a uniform temperature of 325?F. As …
The Use Of Perlite As An Adsorbent, John Herrick Eigler
The Use Of Perlite As An Adsorbent, John Herrick Eigler
Theses
The adsorptive properties of perlite, an expanded volcanic glass, have been studied. Several activating treatments were investigated, air oxidation it 400 degrees Centigrade appears to be the best, The adsorption of the basic dye emethylene blue yields a saturation valve of 50 milligrams per gram of perlite. The acid dye cotton blue showed no measurable adsorption. A maximum adsorption of 15 millimoles of acetic acid and one milligram of iodine were found in aqueous solution. A high value of 1.33 milligrams of iodine per gram of perlite were found in methyl alcohol solutions. The surface area of perlite appears to …
Aryl Sulfonation In Presence Of Phosphrous Trichloride, William Calvert Tanner
Aryl Sulfonation In Presence Of Phosphrous Trichloride, William Calvert Tanner
Theses
With sulfuric acid as the sulfonating agent, phosphorus trichloride is demonstrated as being effective in facilitating the sulfonation of some aromatic compounds. Optimum conditions are a molar ratio of 0.5 mole of sulfuric acid: 1.0 mole of aromatic compound with 4 - 5% more phosphorus trichloride than is required to react with the available water in the system, and reaction temperatures between 50°C. and 60°C.
The aromatic compounds studied were benzene, chlorobenzene, bromobenzene, and nitrobenzene.
The Three Phase System N-Hexane - Aniline - Water, Charles S. Potosnak
The Three Phase System N-Hexane - Aniline - Water, Charles S. Potosnak
Theses
This is a study of the three phase system - n-Hexane Aniline - Water at 50° Centigrade. The data obtained, coupled with data previously established at 36° Centigrade is used to predict a means of recovering aniline from 3-5% aqueous solutions by scrubbing with n-hexane.
Liquid-Gas Flow In Venturi Meter And Sharp Edged Orifice, Frank John Chwalek
Liquid-Gas Flow In Venturi Meter And Sharp Edged Orifice, Frank John Chwalek
Theses
The results of a study of pressure drops across a 5/32 inch throat venturi meter and a 5/32 inch thin plate sharp-edged orifice for the horizontal cocurrent, flow of the air-water two-phase two-fluid system in a 3/4 inch pipe under essentially isothermal conditions, are presented. This is the first critical study of two phase flow in a Venturi meter and. in a 5/32" orifice.
Flows of water of 0.1 to 1.7 gallons per minute with air rates in range of 0.00022 lbs/sec. to 0.0092 lbs/sec. of air mixed in were studied. All flows were turbulent when judged with the conventional …
Hydrolysis Of Sodium Silicofluoride, Frank Arthur Graf
Hydrolysis Of Sodium Silicofluoride, Frank Arthur Graf
Theses
The kinetics of an apparent solubility decrease of commercial sodium fluoride encountered in a piece of equipment designed to produce saturated sodium fluoride solution was Investigated, in order to understand why a consistently saturated solution was not possible to achieve with plain tap water as solvent.
The main impurity, about 1 percent sodium silicofluoride, coats the sodium fluoride crystals, resulting in an equilibrium shift during dissolution of the salt in water; and under certain conditions results in the formation of a protective gel. Therefore, in order to produce a constant strength sodium fluoride solution, this coated impurity must be decomposed …
Ammonia Catalized Phenol Formaldehyde Resins, Murlin Charles Ehrgott
Ammonia Catalized Phenol Formaldehyde Resins, Murlin Charles Ehrgott
Theses
The literature on ammonia-catalyzed phenol-formaldehyde resins is reviewed and critical comparisons are made of the manner in which the ammonia-catalyzed resins differ from both the alkali- and acid-catalyzed resins.
Intermediate products formea during the initial stapes of the ammonia-catalyzed phenol-formaldehyde reactions, as reported in the literature, are tabulated and % N contents are calculated.
Experimental determinations of N content of resins with molar ratios of 1:1.25 phenol to formaldehyde with ammonia at 0.2, 0.5, and 1.0 moles per mole of phenol, show that at the 0.2 molar ratio of ammonia, all the N enters into the resin and remains during …
Prediction Of Vapor-Liquid Equilibria, Daniel James Mchale
Prediction Of Vapor-Liquid Equilibria, Daniel James Mchale
Theses
Several equations for predicting vapor-liquid equilibria from the physical properties of the components have been proposed in the literature. Two equations of this type proposed by O. Redlich and others have been investigated to determine their utility.
Results indicate the two equations give fairly satisfactory results for nearly ideal solutions, but are unsatisfactory for non-ideal solutions. Knowledge of molecular interactions in the solution would be necessary before the predictions could be used with confidence.
Use Of Liquid Sulfur Trioxide As A Sulfonating Agent For Organic Compounds, Herman Gustav Weiland
Use Of Liquid Sulfur Trioxide As A Sulfonating Agent For Organic Compounds, Herman Gustav Weiland
Theses
Dodecylbenzene was sulfonated with SO3 and evaluated as to ash, sodium sulfate, degree of sulfonation, and was also compared with an oleum sulfonation. Its homolog, octadecylbenzene, was made, sulfonated, and found to be less effective as a wetting agent.
Two-ethylhexyl cinnamate, oleic acid, and propyloleate were also sulfonated with good yields and evaluated.
Yields in the sulfonation of Di-2-ethylhexyl maleate were very low. There was evidence of the SO3 splitting the ester and oxidising it to maleic acid.
The reduction of 9-octadecenophenone, according to Clemmenson's Method, led to the formation of a polymer.
Esters Of Sulfanilic And Substituted Sulfanilic Acids, Stephen James Kovalsky
Esters Of Sulfanilic And Substituted Sulfanilic Acids, Stephen James Kovalsky
Theses
Attempted esterification of p-acetaminobenezenesulfonyl chloride with any of the low molecular weight alcohols in aqueous systems always results in the formation of sulfanilic acid. When conducted in a non-aqueous medium, the desired esterification did not occur. A water soluble compound formed, instead, which has not yet been identified.
A study was made of sulfanilic acid esters. Alcoholysis reactions involving the butyl ester and methyl alcohol were successful only when the reaction was conducted under pressure and under anhydrous conditions.
The Preparation Of 2-Aminophenol-4-Sulfonic Acid From Sulfanilic Acid, Edward Jacob Mach
The Preparation Of 2-Aminophenol-4-Sulfonic Acid From Sulfanilic Acid, Edward Jacob Mach
Theses
Sulfanilic acid (I) was examined for purity and character. Sodium and potassium salts were acetylated and their isolation and yields were investigated.
The salts were nitrated with mixed acids and the reaction mixtures were treated in various ways to ascertain a good method for isolating the desired 2-nitro-sulfanilic acid (II). An attempt was made to characterize the reaction products, and to devise quantitative methods to estimate the yield of 2-nitrosulfanilic acid. A previously unreported by-product of the nitration, 2,4,6-tri-nitroaniline (He), was isolated. Several new salts of 2-nitrosulfanilic acid were prepared, and a possible new derivative was observed from the reaction …
Linear Growth Rates Of Single Copper Sulfate Crystals, Arthur Oswald Hansen
Linear Growth Rates Of Single Copper Sulfate Crystals, Arthur Oswald Hansen
Theses
The purpose of this work was to study and measure the factors influencing crystal growth.
Approximately 250 single crystals of CuSO4.5H2O were grown under controlled conditions of supersaturation, solution velocity, and temperature.
The data from this work indicates that:
(a) Crystal growth rate is independent of crystal size for the size range covered (4 to 12 mesh).
(b) Crystal growth rate is directly proportional to the degree of supersaturation, or driving force for each concentration of solution studied.
(c) Crystal growth rate varies exponentially with the velocity of the solution passing the crystal
RD = …
Heat Capacities Of Ethane Over A Wide Range Of Temperature And Pressure, Thomas Agens Reiter
Heat Capacities Of Ethane Over A Wide Range Of Temperature And Pressure, Thomas Agens Reiter
Theses
The effects of pressure and temperature on the isobaric heat capacity, the constant volume heat capacity, and the ratio of heat capacities of ethane are presented. The range of conditions covered are pressures from 0 to 10,000 psia and temperatures from 180 to 1400°F. The calculation of these effects is based on equations derived from the Benedict-Webb-Rubin equation of state. The derived equations express the deviations of the heat capacities from ideal gas behavior.
The results show that ignoring the effect of pressure en the heat capacities of ethane may lead to large errors in engineering calculations. Graphs and tables …
Investigation Of The Acid Degradation Of 2-(4-Methoxybenzylamino)-Pyridine, Anthony Thomas Oropollo
Investigation Of The Acid Degradation Of 2-(4-Methoxybenzylamino)-Pyridine, Anthony Thomas Oropollo
Theses
This paper represents work done in connection with an investigation of the products resulting from the reaction of dilute sulfuric acid and 2-(4-methoxybenzyl-amino)-pyridine. Brief contact between these reactants at temperatures below 80°C give rise to a water soluble salt of the amine. The amine may be precipitated from the solution by the addition of sufficient alkali.
Under the conditions considered in this paper, prolonged contact of reactants at temperatures above 80°C, a non-crystalline condensation product is obtained in addition to the amine salt.
Attempts to identify this product were unsuccessful. However, in connection with the characterization work, two relatively little …
I. Certain Azo Dyes Derived From 2-Amino Phenol-4-Sulfonic Acid; Ii. A Study Of The Reduction Rate Of 2-Nitro Phenol-4-Sulfonic Acid, Albert Edward Cohen
I. Certain Azo Dyes Derived From 2-Amino Phenol-4-Sulfonic Acid; Ii. A Study Of The Reduction Rate Of 2-Nitro Phenol-4-Sulfonic Acid, Albert Edward Cohen
Theses
No abstract provided.
The Development Of Executives, Joseph Ralph Messineo
The Development Of Executives, Joseph Ralph Messineo
Theses
The ever-increasing trend toward improved industrial efficiency creates the problem of supplying capable executives. The supply of executive manpower in business corporations ever needs replenishing. Expansion of operations, retirements, and other circumstances cause executive demands and vacancies which must be filled. Therefore, the purpose of this thesis is to analyze and report on what industry is actually doing today to develop executives to meet present and future requirements. Also, it is the author's intent to formulate a comprehensive executive development program that can be adopted with some limitations by industry for the building of an executive reserve.
In order to …
Vapor Phase Catalytic Air Oxidation Of P-Cymene, Salvatore Joseph Finelli
Vapor Phase Catalytic Air Oxidation Of P-Cymene, Salvatore Joseph Finelli
Theses
No abstract provided.