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Articles 661 - 690 of 969
Full-Text Articles in Chemical Engineering
The Effect Of Flow Rate And L/D Ratio On The Frequency Response Of Water Fluidized Beds, Arnold Ludke
The Effect Of Flow Rate And L/D Ratio On The Frequency Response Of Water Fluidized Beds, Arnold Ludke
Theses
In this investigation, the dynamics of a water fluidized bed with varying L/D ratio and flow rate were analyzed both theoretically and experimentally, and the results of the two were compared.
The theoretical analysis was based on the standard method of Laplace transforms and transfer function synthesis.
The experimental investigation was conducted using standard frequency response techniques.
The mathematical model used consisted of a series of non-interacting perfectly mixed cells plus a distance velocity lag.
At low flow rates (3 to 6 times minimum fluidization velocity) the experimental data (in the form of Bode plots) were found to be in …
Thin Layer Ionophoresis Of Sugars, Joseph Gilbert Vrindten
Thin Layer Ionophoresis Of Sugars, Joseph Gilbert Vrindten
Theses
In 1952, Consden and Stanier published a report on paper ionophoresis of sugars in which they showed experimentally an increase in mobility of sugars with increasing pH in borate buffers. The object of the experiments in this thesis was to determine if this finding was also true of thin layer plates, there being no published literature on similar experiments using thin layer ionophoresis.
Glass plates 20 cm. x 20 cm. were coated with a 300 micron layer of cellulose powder and dried at 105° C. for one hour. They were then stored in an airtight tin box until ready for …
A New Technique For The Solution Of Free Convection Mass Transfer Boundary Value Problems, James Lewis Putman
A New Technique For The Solution Of Free Convection Mass Transfer Boundary Value Problems, James Lewis Putman
Theses
Free convection mass transfer in boundary layer flow due to density difference in an isothermal model was studied. Previous work was examined and a quasilinearization technique was chosen to linearize the system of nonlinear partial differential equations resulting from the boundary layer continuity, momentum, and diffusion equations. This system of linear ordinary differential equations was solved by a computer program utilizing an iterative Gauss Jordan matrix solution technique. Results are presented and the convergence rate of the variables is plotted for each variable as a function of the distance from the boundary layer.
Enthalpy Deviations For The System Methane - Carbon Dioxide, Fred S. Winter
Enthalpy Deviations For The System Methane - Carbon Dioxide, Fred S. Winter
Theses
Enthalpy deviations for the gaseous system, Methane and Carbon Dioxide were developed using the Redlich-Kwong equation of state. Values of enthalpy deviation were obtained at 0.0, 0.0852, 0.19912, 0.3583, 0.6685 and 1.0 weight fraction Methane, at temperatures of 100° F, 280° F and 460° F, at pressures between 200 and 10,000 PSIA.
A computer program in Fortran IV language was developed for solving the Redlich-Kwong equation in terms of the compressibility factor.
The Redlich-Kwong expression for enthalpy deviation, in combination with graphical methods was used to produce the results.
Rheology Of Asbestos Filled Polystyrene, Richard Henry Young
Rheology Of Asbestos Filled Polystyrene, Richard Henry Young
Theses
A capillary rheometer was used to generate data showing the volumetric flow rate at various pressures for a polystyrene resin and for an asbestos filled polystyrene. Variables evaluated were per cent asbestos and temperature. These data were then used to calculate the maximum shear stress at the capillary wall and the corresponding maximum velocity gradient (shear rate) at the capillary wall. A rheological equation containing three constants was employed to relate the shear stress to the shear rate. In addition, a simple relationship was found between the values of two of the constants and the per cent asbestos. There is …
P-V-T Properties Of Hydrogen And Mixtures Containing Hydrogen (With A Generalized B-W-R Equation Of State), Arnold Brief
P-V-T Properties Of Hydrogen And Mixtures Containing Hydrogen (With A Generalized B-W-R Equation Of State), Arnold Brief
Theses
A Generalized B-W-R Equation of State is tested for hydrogen which is a quantum gas and for systems containing hydrogen.
The gases and systems studied are: hydrogen, nitrogen-hydrogen methane-hydrogen and ethane-hydrogen.
The pressure is calculated using observed P-V-T data and the deviation is computed therefrom. For the pure gas, hydrogen, the generalized equation is compared against the original B-Vi-R equation. For mixtures, the Gunn-Chueh-Prausnitz method which is used to calculate the pseudo-critical conditions of the mixture is compared against the Prausnitz-Gunn method.
The ranges studied in this paper are as follows:pure hydrogen 30-773°K and 1 to 1200 atm., n itrogen-hydrogen …
A Rheological Equation Of State For Blood At Low Shear Rates, Anatoly Dritschilo
A Rheological Equation Of State For Blood At Low Shear Rates, Anatoly Dritschilo
Theses
In this work a new rheological equation of state is presented and its application to blood is studied. The equation considered is a linear combination of Newtonian and non-Newtonian contributions to the apparent viscosity. The general form of the equation is
Tij =-(A + Be-1/C|(.5)Δi/j:Δj/i|1/2)Δij
Data from the literature were used to test the equation by generating curves of measured torque (T/L) versus applied shear rate (Ω) that would characterize the behavior of blood at all red cell concentrations and all shear rates in the Gilinson, Dauwalter and Merrill viscometer. The constants for the equation were …
Computer Specification Of Centrifugal Pump And Motor, Paul David O'Lenick
Computer Specification Of Centrifugal Pump And Motor, Paul David O'Lenick
Theses
The purpose of this thesis is to develop a PORTRAIT computer program for selecting a centrifugal pump and motor driver. This is accomplished by means of generalized data which establishes the speed of the Dump and its power requirement. After selection of the pump, the motor is sized and specified. In addition to determining the pump and motor, the program also sizes the discharge and suction lines and the required control valve. The resulting solution yields the pump design data, motor, line and control valve sizes. From this data utility and relative equipment costs can be estimated.
Boiling Heat Transfer In The Presence Of Electric Fields, Ronald Francis Lovenguth
Boiling Heat Transfer In The Presence Of Electric Fields, Ronald Francis Lovenguth
Dissertations
The effects of a non-uniform, radial D.C. electric field on the natural convection and nucleate boiling regimes in saturated pool boiling and on the peak heat flux phenomenon were determined for trichlorotrifluoroethane, carbon tetrachloride, dichloromonofluoromethane and chloroform using as a heat transfer surface a 0.02 inch diameter platinum wire.
Bubble departure diameters for the nucleate boiling region were measured by photographic means as a function of the electric field intensity at the heat transfer surface.
The application of an electric field was found to have a significant effect on the natural convection mode of heat transfer and also the peak …
Viscosity-Density Correlation Of Newtonian Liquids, Melvin Leonard Druin
Viscosity-Density Correlation Of Newtonian Liquids, Melvin Leonard Druin
Dissertations
The viscosity of monatomic liquids was modeled by an equation derived from the kinetic theory of gases. Viscosities may be calculated from data on density and molecular weight of the liquid. In adapting this relationship to polyatomic liquids, a single correction factor was developed for each of five series of homologues; n-paraffins, n-1 -alkenes, n-alkylcyclohexanes, n-alkylbenzenes and n-alcohols, to account for the deviations of the calculated viscosities from those reported, extending over a one- to three-hundred degree range. The factor is a function of reduced temperature relative to the normal boiling point, TrB. A single equation for each …
The Generalized Virial Equation Of State, Ghanshyam R. Patel
The Generalized Virial Equation Of State, Ghanshyam R. Patel
Dissertations
A generalized three parameter virial equation of state has been developed and tested for seven pure gases having different molecular characteristics. The equation has also been tested for more than thirteen binary gas mixtures using three different mixture rules. The final equation is as follows:
Z = 1 + B(T)/V + C(T)/V2 + D(T)/V3 + E(T)/V4 + VF(T)/eaV + VG(T)/ebV
The expressions for E(T), F(T), and G(T) along the critical isotherm were derived in terms of critical properties and two constants, a and b which appear in the sixth and seventh terms in the above …
The Optimization Of A Catalytic Methanol Reactor, Peter Wrampe
The Optimization Of A Catalytic Methanol Reactor, Peter Wrampe
Theses
The development of a computer program which determines the minimum space time of the methanol synthesis reactants is presented. Also, the optimum temperature profile along the catalytic reactor was predicted for a desired conversion at a given operating pressure, feed composition, and catalyst effectiveness factor.
The equilibrium conversion of methanol was determined at various reaction parameters. Rates of reaction were ascertained and maximized with respect to temperature for various conversions and given reaction parameters. The results, along with those obtained when the design equation was numerically integrated, were compared to published data. Equations were established for various sets of published …
The Effect Of Nitrilotriacetic Acid Upon The Biodegradability Of Linear Alkyl Benzene Sulfonate, John D. Mckenna
The Effect Of Nitrilotriacetic Acid Upon The Biodegradability Of Linear Alkyl Benzene Sulfonate, John D. Mckenna
Theses
The effects of trisodium nitrilotriacetate (SKTA) and sodium tipolyphosphate (STPP) upon the biological degradation of linear alkyl benzene sulfonate (LAS) ware experimentally investigated by the chemical oxygen demand and methylene blue methods. It was found that when STPP was present with LAS, the degradation of the LAS was better than when alone in solution. It was also found that LAS in solution with SN TA was less degradable than LAS alone. The benzene ring of the MS appeared to degrade after most of the linear portion of the chain had already been degraded.
Premix Molding Compounds : The Effect Of Processing Technique On Profitability And Product Integrity, Albert Robert Kurkowski
Premix Molding Compounds : The Effect Of Processing Technique On Profitability And Product Integrity, Albert Robert Kurkowski
Theses
Premix molding compounds, presently manufactured in a double-armed blade kneader mixer, can now be prepared by a new and unique method utilizing a high speed densifier. Compounds processed in a kneader mixer, by virtue of its overlapping, shear mixing motion, are extremely susceptible to glass fiber degradation and. consequent mechanical strength reductions in moldings. Previously, as this was the only equipment, available with the capability to admix highly viscous materials, processors would formulate and design to compensate for the resultant property reductions that are encountered. Also typical of conventional kneader mixer processes is an inherent materials handling problem and mixing …
Effect Of Column Diameter On The Frequency Response Of Water Fluidized Beds, Edward C. Maiuro
Effect Of Column Diameter On The Frequency Response Of Water Fluidized Beds, Edward C. Maiuro
Theses
The effect of column diameter on the frequency response of water fluidized beds was investigated.
Studies were made on four columns ranging from four to ten inches in diameter. Water was used to fluidize the beds which consisted of spherical glass beads .0185 inches in diameter. A trace solution of sodium chloride was sinusoidally introduced into the beds. Inlet and outlet concentrations were continuously measured by an electrical conductivity recorder. Separate frequency response tests were conducted on the inlet calmning section in an attempt to obtain the frequency response of this region alone. Results of the tests were expressed as …
The Plasticization Of 4-Methyl-Pentene-1 (Tpx-Rt-D30) Polymer With Petroleum Jelly, Joseph P. Mccann
The Plasticization Of 4-Methyl-Pentene-1 (Tpx-Rt-D30) Polymer With Petroleum Jelly, Joseph P. Mccann
Theses
The properties of TPX-RT-D30 (4-methyl-pentene-1 polymer) have been changed by blending petroleum jelly with the polymer. The polymer was blended in a Brabender apparatus with up to 40% by weight petroleum jelly (P.J.) at 270°C, pressed and quenched in water. Samples were die cut for the various tests. The polymer tensile properties (ASTM-638-64T) showed both a break and yield value in all ratios as compared to only a break value for the TPX-RT polymer. Breaking strength ranged from 4000 psi for pure TPX-RT down to 1000 psi at 40% P.J., with a leveling point of 2000 psi at 15% P.J. …
Critical Interaction Constants For Binary Gas Mixtures For Use In The Redlich-Kwong Equation Of State, Warren J. Biss
Critical Interaction Constants For Binary Gas Mixtures For Use In The Redlich-Kwong Equation Of State, Warren J. Biss
Theses
In this work, critical interaction constants were used to evaluate the interaction coefficients of the Redlich - Kwong constants for bin-ary gas mixtures. From these constants, the pressure - volume - temperature behavior of the mixtures was calculated using the Redlich - Kwong equation.
The critical interaction constants, T12 and P12 , were evaluated for binary mixtures by solving, simultaneously, two second degree equations relating terminal slopes for critical pressure loci and the mole fractions of the components present. The feasibility of this method was tested by calculating P-V-T data for binary mixtures and comparing this with values …
A Correlation Of Latent Heats And Densities Of Pure Organic Liquids From Known Vapor Pressure Data, Vincent J. Vasta
A Correlation Of Latent Heats And Densities Of Pure Organic Liquids From Known Vapor Pressure Data, Vincent J. Vasta
Theses
Employing the correlation developed by Kemme (5), which is based on a hole model for a liquid, relating vapor pressures with corresponding liquid densities and the number of carbon atoms in a molecular chain for a homologous series, correlation coefficients were established using multi-linear regression analysis on available literature data. This correlation was newly applied to several straight chain homologous series including the n-acids, formate esters and n-alkyl benzenes.
A second correlation developed by Kemme (5) relating vapor pressure, internal heat of vaporization and the number of carbon atoms for a homologous series was employed to determine correlation coefficients for …
Liquid Vapor Equilibrium In Nucleate And Film Boiling, Walter Henry Rothaug
Liquid Vapor Equilibrium In Nucleate And Film Boiling, Walter Henry Rothaug
Theses
Liquid vapor equilibrium data were obtained for several solutions and azeotropes under both nucleate and film boiling. The data were invariant between the two boiling regimes indicating that both nucleate and film boiling are equilibrium vaporizations rather than either diffusional or bulk vaporizations. Boiling heat transfer versus temperature data were taken in nucleate and film boiling for the solutions and azeotropes and for several pure liquids. The critical heat flux for methyl alcohol-benzene solutions rose sharply at first and then more moderately with increasing alcohol concentration. The critical heat flux was pratically constant regardless of concentration in ethyl alcohol-benzene solutions. …
Relationships Between Some Properties Of Pure Homologous Organic Liquids, Herbert Rudolph Kemme
Relationships Between Some Properties Of Pure Homologous Organic Liquids, Herbert Rudolph Kemme
Dissertations
The vapor pressures of eleven primary straight chain alkyl chlorides and eleven primary straight chain alcohols between C3 and C16 were determined within a range of 5 to 760 mm Hg. These data were obtained by determining the boiling points of the pure materials at various pressures by using differential thermal analysis. The boiling points were determined with a precision of -.1 degree Centigrade at a 95 per cent C.I. The Antoine equation was used to analytically describe the data. The constants for this equation were determined by a multiple linear regression technique for each individual compound. The heats of …
Kinetics Of Hydrogen Reduction By Manganese Dioxide, Herbert Eugen Barner
Kinetics Of Hydrogen Reduction By Manganese Dioxide, Herbert Eugen Barner
Dissertations
Samples of synthetic pyrolusite were reduced in hydrogen at various partial pressures in the temperature range of 200° to 500°C. Most reduction experiments were conducted using a Pyrex vertical-tube reactor, in which small beds of porous particles (0.07 to 0.21 mm.) or single porous pellets of the oxide were suspended. The reaction kinetics were followed by recovering and weighing the water product formed during measured time intervals, and the intermediate reduction products were identified by X-ray diffraction analysis.
The data show that reduction proceeds through the sequence MnO2->Mn2O3->OMn3O4- …
The Reaction Of Cyclic Acetals With N-Halo Compounds, Nicholas Hrinkevich
The Reaction Of Cyclic Acetals With N-Halo Compounds, Nicholas Hrinkevich
Theses
Chemical reactions were carried out to determine the products of the halogenation of cyclic acetals with N-halo compounds (specifically N-bromosuccinimide and N-chlorosuccinimide) under conditions essentially free of those directly associated with free radical mechanisms (photocatalysis, peroxides, azonitriles, etc.).
Cyclic acetals were prepared and halogenated with bromine (Br2) or N-bromosuccinimide (NBS) or N-chlorosuccinimide (NCS). The distilled product from each reaction after workup was analyzed by vapor phase chromatography (VPC). The major components from the VPC were collected and identified by either infrared (IR) or nuclear magnetic resonance (NMR) spectroscopy and elementary analysis.
A mixture of compounds was found in each distilled …
A Computer Program For Multicomponent Distillation From Start Up To Steady State, Leo Julian
A Computer Program For Multicomponent Distillation From Start Up To Steady State, Leo Julian
Theses
A computer program is presented which develops for a multicomponent distillation column a composition and temperature profile as a function of time from initial start-up to steady-state conditions.
The program is written in Kingston Fortran II language for use on an IBM 1620 II machine. It is a Thiele-Geddes type solution, i.e. the total number of plates, feed plate, overhead and bottoms split are specified and the solution gives plate. compositions and temperatures. The material balance at any time is based on the composition at the previous time, increased (or decreased) by the net quantity added and removed as a …
Approximation Of Reaction Rate Models, Hsu-Tung Lee
Approximation Of Reaction Rate Models, Hsu-Tung Lee
Theses
In reaction rate studies, experimental data is interpreted and correlated in terms of various mathematical models. The converse of the modeling of practical problems is the task- of experimental determination of reaction mechanisms. Generally, this approach is classified into integral and differential methods. Both involve trial and error techniques. The mathematical model which satisfies the test becomes the equation for mechanistic representation.
Both the integral and differential methods have been tried. Generally speaking, the differential method is more advantageous than the integral. For one thing, the parameters which are involved in the nodal can be determined directly by the differential …
The Measurement Of Dispersion Coefficients, John Harold Rosenberger
The Measurement Of Dispersion Coefficients, John Harold Rosenberger
Theses
This work describes a method of determining axial dispersion coefficients in a packed bed chemical reactor. This is done by measurement of the fractional conversion of acetic anhydride to acetic acid, by first order reaction in dilute solution. The reaction is carried out at various flow rates in a four inch diameter reactor packed with one-half inch Raschig rings. analysis is by the aniline-rater method. Calculation of the dispersion coefficients is by trial using a digital computer. The results are presented graphically and compared to results obtained by other methods. The results of this study are found to correspond to …
Open-Loop Frequency Response Analysis Of A Jacketed Kettle With Internal Heating/Cooling Coil, Wayne P. Brenckle
Open-Loop Frequency Response Analysis Of A Jacketed Kettle With Internal Heating/Cooling Coil, Wayne P. Brenckle
Theses
This work was performed to investigate the response and stability of a jacketed kettle with internal heating/cooling coils and glasteel thermowell. This system was first analyzed mathematically by deriving transfer functions for each component and then combining all component equations together to give the overall system transfer function. The mathematical model was then checked by frequency response analysis of the system. Bode plots of the system were prepared and the effect of the thermowell was analyzed.
Nyquist plots of the system were used as the criteria for determining stability, and obtaining the open-loop gain necessary to give optimum closed-loop response. …
Heat And Mass Transfer In The Absence Of Air, James Joseph Howley
Heat And Mass Transfer In The Absence Of Air, James Joseph Howley
Theses
The effects of heat and mass transfer across a frosted heat exchanger operating in the absence of air was evaluated. It is felt that this work could be applied to processes such as desalination of water or the purification of materials by reverse sublimation.
The system consisted of a single 1/2” O.D. stainless steel tube mounted within a 3" O.D. plexiglas tube with the ends suitably flanged. A vacuum was maintained in the annular space. Refrigerated ethylene glycol passed through the inner tube in laminar flow. A series of runs with substantially air-free water vapor added to the annular space …
Thermal Conductivity Of Mixtures, Paul Joseph Orosz
Thermal Conductivity Of Mixtures, Paul Joseph Orosz
Theses
A concentric cylinder type cell was designed and constructed tp measure thermal conductivity of liquids. The materials of construction were stainless steel and teflon, so that a wide variety of liquids could be tested.
The systems studied were aqueous solutions of methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, and tertiary-butyl alcohol. Thermal conductivity was studied as a function of composition.
The data obtained were fitted to quadratic equations by least squares analysis. For each system, an equation of the following type was obtained:
kL = A + BxA + CxA2
where kL is thermal …
An Investigation Of Some Properties Of Liquids Near Their Freezing Points, Martin Irwin Pulver
An Investigation Of Some Properties Of Liquids Near Their Freezing Points, Martin Irwin Pulver
Theses
Five normal alcohols were prepared to greater than 99% purity. Simultaneous viscosity and density measurements were made beginning at 20°C above the reported normal freezing point and ending at incipient crystallization.
It was assumed that viscosity could be expressed as a function of specific volume and absolute volume, and that a simple logarithmic function would give a suitable correlation. The resulting equation yielded viscosities with an average error of less than 0.8% for the entire collection of data.
Deviations from a previously established linear function were observed in the density data from about 5°C above the reported normal freezing point …
Natural Gas Liquefaction, Travis George Hutchinson
Natural Gas Liquefaction, Travis George Hutchinson
Theses
In this thesis the author has developed a new process by which natural gas is converted into its liquid form. This has been accomplished by cryogenically cooling, condensing and fractionating natural gas. Resultant from this process is the design of natural gas liquefaction with valuable by-product recovery.