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Correlation Of Drag Reducing Data In Dilute Polymer Solutions, Jorge Mario Rodriguez

Masters Theses

"The purpose of this investigation was to obtain a correlation for drag reducing solutions in circular tubes under turbulent conditions. Data were taken for three polymer-solvent systems: polymethyl methacrylate V-100 (M_v ~ 110,000) in toluene, polyisobutylene L-200 (M_v ~ 4,700,000) in toluene, and polyisobutylene L-200 in cyclohexane. The data from the two polyisobutylene systems, together with other data on polymethyl methacrylate G (M_v ~ 1,500,000) in toluene and polyisobutylene L-80 (M_v ~ 860,000) in cyclohexane, were used to attempt to obtain the correlation. The V-100 solutions were not used because they were not drag reducing.

The …

The Anodic Oxidation Of Maleic Acid, Larry D. Gilmartin

Masters Theses

"The purpose of this investigation was to determine the mechanism of the anodic oxidation of maleic acid on platinized-platinum electrodes at 80⁰C. Current density-potential studies were conducted varying the parameters of maleic acid concentration and pH. The faradaic efficiency of the oxidation of maleic acid to yield CO₂ was determined. The effect of temperature on current density was also studied to determine the activation energy for the reaction. The oxidation of maleic acid occurred only in acidic solutions. The faradaic efficiency was found to be approximately 97 ± 5 per cent. A linear Tafel region was found which had a …

Anodic Dissolution Of Lead In Aqueous Solutions, Christopher Kuo-Chieh Wu

Masters Theses

"The apparent valence of lead was determined in one normal solutions of potassium nitrate, ammonium acetate, lead nitrate, and lead acetate at temperatures of 25 and 50°C. The current density was varied from 0.001 to 1.00 amp•cm ^-2. The apparent valence of lead ranged between 1.90 and 2.00 in all solutions. The lower valences were reached at higher current densities. The amount of disintegration was very small, and was dependent upon film formation on the surface of the anode.

Potential-current density relationships for the anodic dissolution of lead were obtained in the electrolytes mentioned above. In potassium nitrate and …

Study Of Mass Transfer Through Porous, Water-Repellent Membranes, Virendra V. Tanna

Masters Theses

"A new method of desalination using a porous, water-repellent membrane was studied. The membrane utilized surface forces to support a vapor phase in its pores which separated the salt water from fresh water. The method used a vapor pressure difference across the membrane as the driving force for mass transfer of water from the salt water phase to the fresh water. This vapor pressure difference was obtained by maintaining a temperature difference between the two liquid phases.

The experimental data and results indicated the feasibility of vaporization through porous, water-repellent membranes. The flux of water through a membrane made of …

Nucleate-Boiling Heat Transfer To Water At Atmospheric Pressure, H. D. Chevali

Masters Theses

"The purpose of this investigation was to study the hysteresis effect, the effect of micro-roughness and orientation of the heat-transfer surface, and the effect of infra-red-radiation-treated heat-transfer surfaces on the nucleate-boiling curve.

It has been observed that there exists no hysteresis effect for water boiling from a cylindrical copper surface in the nucleate-boiling region over the range studied. The nucleate-boiling curve has been found to be independent of micro-roughness and orientation of the heat-transfer surface. There was no detectable change in the nucleate-boiling characteristics of the heat-transfer surface when the surface was treated with infra-red radiation"--Abstract, page ii.

Study Of Heat And Mass Transfer Through Non-Wettable Porous Membrane, Rajender Kumar Rohatgi

Masters Theses

"The object of this investigation was to study the use of non-wettable porous membranes for simultaneous heat transfer and mass transfer of water from a hot salt solution stream to a cold distilled water stream, the streams being in countercurrent flow separated by the membrane. This type of mass transfer was achieved in the experiments, and mass and heat transfer coefficients were measured.

The membranes studied in this work were made of fiberglas treated with Teflon dispersion and aluminum sulphate. The fiberglas membranes yielded desired results. Empirical correlations were proposed which predict values of heat and mass transfer coefficients close …

The Anodic Oxidation Of Crotonic Acid In Basic Solutions, Richard C. Porter

Masters Theses

"The purpose of this study was to investigate the anodic oxidation of crotonic acid in basic solutions. Potassium hydroxide solutions of pH 12.3 and KOH-K₂CO₃ solutions of pH 11.5 and 10.5 were used. The investigation was carried out on platinized-platinum anodes at 80°C.

Experimental studies were conducted to determine the effects of crotonic acid concentration, pH, and temperature on the current. Faradaic efficiency was determined by analysis of CO₂ produced and was approximately 100 per cent.

The results were interpreted in terms of a mechanism having the following characteristics:

1. The first electron transfer is the rate …

The Kinetics Of The Reaction Of M-Nitrobenzyl Bromide With Hydroxide Ion In Aqueous-Aprotic Solvent Mixtures, Ramesh Nagindas Sheth

Masters Theses

"The reaction between m-nitrobenzyl bromide and sodium hydroxide in homogeneous aqueous dioxane and aqueous tetrahydrofuran media was studied.

The product of the reaction was identified by infrared, gas chromatography and chemical tests as m-nitrobenzyl alcohol.
The kinetics of the reaction are second order with practically no variation in the rate constants as the % of the organic solvent was changed in the medium. This seems to imply hydrolysis of the organic halide by a process involving both bond-breaking and bond-formation in the transition state.
The activation energy, measured in 50% aqueous dioxane, between 20⁰ and 69.5⁰C at 5 different temperatures, …

Decarboxylation Of Malonic Acid In Aqueous Solutions, Ramesh Natwarlal Gujarathi

Masters Theses

"The rate of decarboxylation of malonic acid in aqueous solutions was studied over a range of concentrations, pH's, and temperatures. The catalytic effect of various divalent metallic ions was also studied at a pH of 0.3. these studies did not support a truly unimolecular decomposition as the experimental order was found to be slightly greater than one. An empirical relation for the rate of decarboxylation was formulated in which the undissociated malonic acid and the monovalent malonate ion were the reactive species.

A possible mechanism of decarboxylation due to solvent activation was postulated. No pronounced catalytic effect due to the …

Mass Transfer In Droplets With Turbulent Internal Circulation - Mathematical Description, Jayantilal Mohanbhai Patel

Masters Theses

"This investigation was carried out to check the accuracy of the eigenvalues, λ_n, calculated by Wellek and Skelland, using some method other than the Rayleigh-Ritz technique and also, to determine the coefficients, B_n in series solution, which were not calculated before.
The eigenvalues were obtained by trial and error procedure using the standard Runge-Kutta method. The coefficients B_n were obtained by using eigenvalues. By using this information the fractional extraction was calculated as a function of droplet contact time.

The Wellek-Skelland modification was also solved by finite difference technique to compute fraction extracted as a function …

The Anodic Dissolution Of Magnesium In Aqueous Solutions, Chen-I Lu

Masters Theses

"The anodic dissolution of magnesium was studied in MgCl₂-KC1 and MgBr₂-KBr mixtures at 25, 40, and 55 °C. The parameters of the study were current density, concentration of magnesium ion, and temperature. The concentration of magnesium ions was varied from 0.001 to 1 N holding the ionic strength constant at 1.5. The weight loss of magnesium from the electrode during electrolysis was determined by weighing the electrode both before and after electrolysis. The current was measured with a sensitive milliammeter. The range of the current densities was varied from 0.001 to 0.1 amps·cm^-2. The …

Anodic Dissolution Of Silver In Aqueous Solutions, B. W. Jong

Masters Theses

"The purpose of this investigation was to study the anodic dissolution of silver in various electrolytes to determine if there existed any deviations from Faraday’s law in nitric acid-silver nitrate solutions. The effect of small additions (10^-4 and 10^-5 N) of Cl^-, SO₄⁼, and CrO₄⁼ on the apparent valence and dissolution potential was also studied. Current densities were varied from 0.00 to 0.07 amp·cm^-2.

Based on the observed apparent valences and a grey film containing metallic particles on the anode surface, it was concluded that deviations from Faraday’s law …

A Study Of The Removal Of Alkyl Benzene Sulfonate By Means Of A Column Packed With Sand Coated With Ferric Oxide, Chang I. Fung

Masters Theses

"Iron, precipitated in the form of hydroxides on sand particles (-48 + 65 mesh) and stabilized by drying at 100°C for 10 hours, was utilized to remove alkyl benzene sulfonate (ABS) from aqueous solutions. Solutions containing a maximum of 5 mg/l ABS were passed through a glass column packed with treated sand. The ABS formed a complex with the iron precipitants which adhered to the sand particles.

Preliminary work, in which solutions containing 10 mg/l ABS were treated with various concentrations of FeCl₂ at the equivalence point (pH about 9.5), verified the fact that ABS could be removed by …

A Crystallographic Study Of The Pbzro₃-Pbtio₃-Bifeo₃ Ternary System., Dannie R. Clarida

Masters Theses

"The purpose of this investigation was to conduct a crystallographic study of the PbZrO₃-PbTiO₃-BiFeO₃ ternary system, where all three components are perovskites. Lead zirconate is antiferroelectric, lead titanate is ferroelectric, and bismuth ferrate is thought to be ferroelectric. X-ray diffraction analysis was employed to determine the crystallographic structure and lattice parameters.

A tetragonal region was found to exist in the area of high PbTiO₃ content. A rhombohedral region occurred in the remainder of the system with high BiFeO₃ and PbZrO₃ content, except for an orthorhombic envelope along the PbZrO₃-BiFeO₃ side of the diagram up to approximately 70 per cent BiFeO₃.The …

Permeability And Additive Sorption And Extraction In Lubricating Greases, Hsiu-Hsiung Lin

Masters Theses

"An important goal in the study of lubricating greases is the determination of the mechanism of additive action in lubricating greases and the effect of additive concentration on the improvement of particular properties. As a step in this direction, one aim of this investigation was an attempt to determine whether grease additives are sorbed on the thickener surface, or are dissolved in the oil phase, or if a combination of these effects prevails. Exploratory sorption and extraction experiments were run by Tu using greases thickened with lithium hydroxystearate and Baragel and using only one concentration of additive. More detailed studies …

Nucleate Boiling Heat Transfer To Liquid Nitrogen At Atmospheric Pressure, Satish R. Parikh

Masters Theses

"The object of this investigation was to study the effect of micro-roughness, a thin layer of oil, and infra-red radiations on the cylindrical heat transfer surface of copper, in liquid nitrogen and at atmospheric pressure during nucleate boiling. An attempt was made to find any possible effect of orientation of the heat transfer element on nucleate boiling. A number of different runs were taken with different degrees of roughness, and different orientation positions. Nucleate boiling has been found to be nearly independent of the heat transfer surface roughness and of orientation while strongly dependent on the chemical nature of the …

Electrodialysis Of Tomato Juice, Raghunath R. Khetan

Masters Theses

"Thermal decarboxylation of carboxylic acids has been helpful in illustrating some fundamentals of reaction kinetics in solution. It has been important in formulation of the theory of unimolecular reactions. It is also used frequently in the synthetical methods of organic chemistry.

In a recent study of the anodic oxidation of malonic acid in sulfuric acid at 80⁰C using a platinum anode, the interpretation of some results was impossible due to the spontaneous decomposition of the malonic acid. As no information is available in the literature about decomposition rates of malonic acid in sulfuric acid at the concentrations used, it was …

The Performance Of A Countercurrent Extraction Column With Vibrated Packing, Mehmet Uran ÖZsoy

Masters Theses

"The performance of a continuous countercurrent extraction column with a packing -- that could be vibrated vertically at various amplitudes and frequencies by a variable speed motor -- was investigated under both non-flooding and flooding conditions using the high interfacial tension benzene-acetic acid-water ternary system. In all the experimental runs, which were sequenced randomly with a full-factorial experiment design, mass transfer of the solute (acetic acid) from the aqueous to the organic phase was studied. Column performance was evaluated in terms of the height of an overall transfer unit, HTU, based on the benzene phase. The variables studied were: amplitude …

The Effect Of Concentration On The Viscosity Of Polyisobutylene Solutions, Lung-Yu Chou

Masters Theses

"In the past twenty years the viscosity of dilute polymer solutions (i.e., where the solute molecules are far apart) has been investigated in great detail, both theoretically and experimentally. The viscosity characteristics of such systems are well-understood.

Only a few studies have been made of the effect of concentration on the viscosity of polymer solutions in the concentration range where the polymer molecules begin to overlap. This range of concentrations is important in practical applications such as dry spinning of fibers, cross-graded automotive motor oils and in many industrial formulations where polymers are used to thicken solvent vehicles. Development of …

Further Studies Of The Catalytic Oxidation Of Ortho-Xylene To Phthalic Anhydride Using A Fluidized Bed Reactor., Richard Shih-Chun Chu

Masters Theses

"This investigation was conducted to further study the vapor-phase oxidation or o-xylene to phthalic anhydride in a fluidized bed catalytic reactor. Parameters investigated during the study were temperature, catalyst volume, and catalyst activated by use or different promoters. Two different vanadium pentoxide catalysts were used. One was a new catalyst(Catalyst I) supported on a silica base and diluted with potassium sulfate. The other catalyst(Catalyst II) was similar to the first one except that it had been used in a commercial fixed bed reactor operated by the Monsanto Company, St. Louis, Missouri, using naphthalene as a reed material. It had been …

Kinetics And Mechanisms Of Base-Catalysed Reactions, Rohit Panalal Sheth

Masters Theses

"Base-catalysed reactions normally involve complex series of transformations. their kinetics is usually governed by a variety of equilibria, participating in the overall and concurrent processes as well as by competitive side-reactions that interfere with the normal course of such reactions. Mechanisms which have been proposed, by and large, are primarily based on product, by-product and intermediate analyses together with some scattered kinetic and isotopic evidence. In the cases where kinetic studies have been attempted, highly complex mechanisms have usually been proposed due to the frequent necessity of using heterogeneous media or employing involved mathematical treatments to describe the kinetics of …

A Study Of Molecular Diffusion In Polymer Solutions By A Microinterferometric Method, Girish T. Dalal

Masters Theses

"A microinterferometric method was used to study the effect of solute concentration on the diffusion coefficient in polymer solutions and also to determine the effect of polymer concentration on the diffusion coefficient. The polyacrylonitrile-dimethylformamide system was used as a means of determining the accuracy of the experimental apparatus and procedure. The non-ionic, water soluble polymer, hydroxyethyl cellulose (commercially known as Natrosol), was used to study this effect with urea and D-glucose as the solutes.

The results obtained for the polyacrylonitrile-dimethylformamide system were in close agreement with the results obtained by Secor, which meant that the experimental technique is accurate enough …