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Articles 1291 - 1320 of 1407

Full-Text Articles in Biochemical and Biomolecular Engineering

Effect Of Culture Conditions, Donor Age, And Injection Site On In Vitro Development Of Dna Microinjected Porcine Zygotes, M A. Hajdu, J W. Knight, R S. Cansecot, R L. Krisher, William H. Velander, R E. Pearson, F C. Gwazdauskas May 1994

Effect Of Culture Conditions, Donor Age, And Injection Site On In Vitro Development Of Dna Microinjected Porcine Zygotes, M A. Hajdu, J W. Knight, R S. Cansecot, R L. Krisher, William H. Velander, R E. Pearson, F C. Gwazdauskas

Papers in Biotechnology

A series of experiments evaluated development of porcine zygotes microinjected with DNA in three culture media and two incubation temperatures, from postpubertal and prepubertal donors, and between zygotes injected with DNA into the pronucleus and the cytoplasm. Zygotes recovered from 36 postpubertal gilts in Exp. 1 were injected and cultured in modified NCSU-23, modified NCSU-37, and CZB media at 37°C or 39°C for 7 d. In Exp. 2, zygotes were collected from postpubertal or prepubertal gilts, microinjected with DNA, and cultured in modified NCSU-23. In Exp. 3 superovulated prepubertal gilts had DNA injected into the cytoplasm or pronucleus of zygotes. …

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Effects Of Time Of Deoxyribonucleic Acid Microinjection On Gene Detection And In Vitro Development Of Bovine Embryos, A.E T. Sparks, R S. Canseco, C G. Russell, J L. Johnson, H D. Moll, William H. Velander, Francis C. Gwazdauskas Mar 1994

Effects Of Time Of Deoxyribonucleic Acid Microinjection On Gene Detection And In Vitro Development Of Bovine Embryos, A.E T. Sparks, R S. Canseco, C G. Russell, J L. Johnson, H D. Moll, William H. Velander, Francis C. Gwazdauskas

Papers in Biotechnology

In vivo fertilized embryos were surgically collected from superovulated dairy cows to evaluate microinjection on embryo development and utilized the polymerase chain reaction technique for selection of transgenic embryos. Seventy-two percent of the embryos with visible pronuclei or nuclei were microinjected with DNA, and the remaining 28% served as uninjected controls. All embryos were cocultured with bovine oviductal epithelial cells. Mean final development scores of embryos within the same initial cell stage at collection were unaffected by microinjection. After 144 h of culture, 45% of the microinjected embryos developed to the morula or blastocyst stage. The transgene was detected in …

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Formation Of Plasma Polymer Thin Films Containing Reactive Metal Chelate Sites, J. M. Skelly, Nicholas C. Morosoff, V. T. Stannett, A. L. Crumbliss Feb 1994

Formation Of Plasma Polymer Thin Films Containing Reactive Metal Chelate Sites, J. M. Skelly, Nicholas C. Morosoff, V. T. Stannett, A. L. Crumbliss

Chemical and Biochemical Engineering Faculty Research & Creative Works

We report here the successful incorporation of chemically active Co2+ and Ni2+ centers into plasma polymer thin films. Metal center incorporation was accomplished by simultaneous plasma polymerization of sublimed Co2+ or Ni2+ complexes with gaseous "comonomers" or Ar. The metal complexes include N,N′-bis(salicylidene)-1,2-phenylenediaminecobalt(II) (CoSalophen), N,N′-bis(salicylidene)ethylenediaminecobalt(II) (CoSalen), N,N′-bis(3-fluorosalicylidene)ethylenediaminecobalt(II) (CoFluomine), meso-tetraphenylporphyrinatocobalt(II) (CoTPP), meso-tetraphenylporphine (TPP), and meso-tetraphenylporphyrinatonickel(II) (NiTPP). Modification to the metal complex structure was observed by IR and UV-vis spectroscopies. IR spectra of plasma polymer films containing the Schiff's base complexes, prepared using Ar as a carrier gas, contained a band at 2190 cm−1, which can be attributed to nitrile group formation, …

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Writing Across The Chemical Engineering Curriculum At The University Of North Dakota, Douglas K. Ludlow, Kirk H. Schulz Jan 1994

Writing Across The Chemical Engineering Curriculum At The University Of North Dakota, Douglas K. Ludlow, Kirk H. Schulz

Chemical and Biochemical Engineering Faculty Research & Creative Works

In Order to Prepare Engineering Graduates with the Written and Oral Communication Skills Needed in their Professional Careers a Coordinated Writing Across the Curriculum (WAC) Program Has Developed in the Chemical Engineering Department at the University of North Dakota. the Students Practice and Develop their Skills with Writing Assignments in Both Lecture and Laboratory Courses from the First‐year Level through the Fourth‐year Capstone Design Course. the Coordinated Approach, especially in the Four‐semester Laboratory Sequence, Allows the Students to Develop their Skills by Building on Communication Experiences in Previous Courses. the WAC Program at UND Including Writing and Public Speaking Assignments …

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Structural Properties Of Mixtures Of Highly Asymmetrical Electrolytes And Uncharged Particles Using The Hypernetted Chain Approximation, Daniel Forciniti, Carol K. Hall Jan 1994

Structural Properties Of Mixtures Of Highly Asymmetrical Electrolytes And Uncharged Particles Using The Hypernetted Chain Approximation, Daniel Forciniti, Carol K. Hall

Chemical and Biochemical Engineering Faculty Research & Creative Works

We have solved the Ornstein-Zernike equation in the hypernetted chain (HNC) approximation for several mixtures of electrolytes and uncharged hard spheres. The mixtures that we studied range from a simple restricted primitive model plus hard spheres of the same size to highly asymmetric electrolytes plus hard spheres of different sizes. We monitored the radial distribution function and thermodynamic properties. We find that the presence of neutral particles changes the nature of the interaction between the charged particles. We also find a strong correlation between nonelectrostatic and electrostatic contributions to the free energy of the mixtures. Potential applications of this approach …

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Dominance Of The Thomas Mechanism For Electron Capture From Orientated Rydberg Atoms, Jee-Ching Wang, Ronald E. Olson Jan 1994

Dominance Of The Thomas Mechanism For Electron Capture From Orientated Rydberg Atoms, Jee-Ching Wang, Ronald E. Olson

Chemical and Biochemical Engineering Faculty Research & Creative Works

We investigate electron capture from initially oriented circular Rydberg atoms by proton impact at collision speeds comparable to the electron orbital speed. The Thomas double scattering mechanism is observed even at these low relative speeds. Furthermore, we find evidence for the dominance of a quasi Thomas capture mechanism in the form of not a single peak, but a double-peaked structure in the differential cross section when the plane of the circular orbit is nearly perpendicular to the incident direction of the projectile. © 1994 The American Physical Society.

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Multiphase Equilibrium Behavior Of The Mixture Carbon Dioxide + Ethane + Methanol, Seung Pyo Hong, Christi L. Patton (Luks), Kraemer D. Luke Jan 1994

Multiphase Equilibrium Behavior Of The Mixture Carbon Dioxide + Ethane + Methanol, Seung Pyo Hong, Christi L. Patton (Luks), Kraemer D. Luke

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Three-Phase Liquid-Liquid-Vapor (Llg) Phase Equilibrium Behavior of the Mixture Carbon Dioxide + Ethane + Methanol Was Experimentally Studied. the Boundaries of the Three-Phase Llg Region in Pressure-Temperature Space Are Delineated. Compositions and Molar Volumes of the Two Liquid Phases and the Vapor Phase Along the 288.15 and 298.15 K Isotherms Are Reported. © 1994, American Chemical Society. All Rights Reserved.

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Final State Distributions For Electron Capture From Orientated Rydberg Atoms, Jee-Ching Wang, Ronald E. Olson Dec 1993

Final State Distributions For Electron Capture From Orientated Rydberg Atoms, Jee-Ching Wang, Ronald E. Olson

Chemical and Biochemical Engineering Faculty Research & Creative Works

Final state nim distributions are studied for electron capture from orientated circular Rydberg atoms. Strong orientation effects are found for all quantum numbers at collision speeds comparable to the electron orbital speed. Predominant population of large m states is observed when the plane of the circular orbit is nearly perpendicular to the incident direction of the projectile. The Ini distributions show structures due to quasi-Thomas scattering even at low relative collision velocities. © 1993 IOP Publishing Ltd.

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Ionic Charge Dependence Of The Zero Degree Binary Encounter Peak For Partially Stripped Heavy Ions, W. Wolff, H. E. Wolff, J. L. Shinpaugh, Jee-Ching Wang, Ronald E. Olson, D. Fainstein, S. Lencinas, U. Bechthold, R. Herrmann, H. Schmidt-Bocking Nov 1993

Ionic Charge Dependence Of The Zero Degree Binary Encounter Peak For Partially Stripped Heavy Ions, W. Wolff, H. E. Wolff, J. L. Shinpaugh, Jee-Ching Wang, Ronald E. Olson, D. Fainstein, S. Lencinas, U. Bechthold, R. Herrmann, H. Schmidt-Bocking

Chemical and Biochemical Engineering Faculty Research & Creative Works

We report on the measurements of double differential cross sections, at zero degree, for the production of secondary electrons from the collision of 0, 6 MeV amu-1 Cu5+, I7+, Au11+, U13+, Cu19+, t23+ and Au29+ projectiles with H2 and He. The shapes and positions of the observed binary encounter electron peaks are compared with continuum distorted wave-eikonal initial state (CDW-EIS), impulse approximation and classical trajectory Monte Carlo calculations, as well as with predictions from an adiabatic resonant tunnelling model recently proposed by Fainstein and co-workers. The …

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Dependence Of Binary Encounter Electron Production On The Charge State Of The Recoil Ion, Jee-Ching Wang, Ronald E. Olson, H. Wolf, J. Shinpaugh, W. Wolff, H. Schmidt Böcking Aug 1993

Dependence Of Binary Encounter Electron Production On The Charge State Of The Recoil Ion, Jee-Ching Wang, Ronald E. Olson, H. Wolf, J. Shinpaugh, W. Wolff, H. Schmidt Böcking

Chemical and Biochemical Engineering Faculty Research & Creative Works

We study the dependence of the production of binary encounter electrons on the charge state of recoil ions for 2.4 MeV u-l Xe21+ on He and Ar. Doubly differential cross sections of electron emission are calculated with the ncrMC method. We find that the contributions to the binary electron cross section from various recoil ion charge states reach a maximum near Ar5+ for the Ar target. In the case of the He target; double ionization dominates over single ionization for alt ejected electron energies above 100 eV. However, an unexpected local drop of double ionization in the …

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Reversible Complexation Of O2 To (Meso-Tetraphenylporphyrinato)Cobalt(Ii) Plasma Polymer And Sublimed Films At Room Temperature, J. M. Skelly, Nicholas C. Morosoff, V. T. Stannett, A. L. Crumbliss Jan 1993

Reversible Complexation Of O2 To (Meso-Tetraphenylporphyrinato)Cobalt(Ii) Plasma Polymer And Sublimed Films At Room Temperature, J. M. Skelly, Nicholas C. Morosoff, V. T. Stannett, A. L. Crumbliss

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

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Lattice Boltzmann Thermohydrodynamics, F. J. Alexander, S. Chen, J. D. Sterling Jan 1993

Lattice Boltzmann Thermohydrodynamics, F. J. Alexander, S. Chen, J. D. Sterling

Business and Information Technology Faculty Research & Creative Works

We introduce a lattice Boltzmann computational scheme capable of modeling thermohydrodynamic flows of monatomic gases. The parallel nature of this approach provides a numerically efficient alternative to traditional methods of computational fluid dynamics. The scheme uses a small number of discrete velocity states and a linear, single-time relaxation collision operator. Numerical simulations in two dimensions agree well with exact solutions for adiabatic sound propagation and Couette flow with heat transfer. © 1993 The American Physical Society.

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High-Level Expression Of A Heterologous Protein In The Milk Of Transgenic Swine Using The Cdna Encoding Human Protein C, William H. Velander, John L. Johnson, Raymond L. Page, Chritopher G. Russell, Anuradha Subramanian, Tracy D. Wilkins, Francis C. Gwazdauskas, Christoph Pittus, William N. Drohan Dec 1992

High-Level Expression Of A Heterologous Protein In The Milk Of Transgenic Swine Using The Cdna Encoding Human Protein C, William H. Velander, John L. Johnson, Raymond L. Page, Chritopher G. Russell, Anuradha Subramanian, Tracy D. Wilkins, Francis C. Gwazdauskas, Christoph Pittus, William N. Drohan

Papers in Biotechnology

Transgenic pigs were generated that produced human protein C in their milk at up to 1 g/liter. The gene construct was a fusion gene consisting of the cDNA for human protein C inserted into the first exon of the mouse whey acidic protein gene. These results demonstrate that the mouse whey acidic protein gene contains regulatory elements that can direct cDNA expression at high levels in the pig mammary gland. Recombinant human protein C that was produced at about 380 pg/ml per hr in transgenic pig milk possessed anticoagulant activity that was equivalent to that of protein C derived from …

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Diffraction In The Binary Encounter Electron Peak Observed In Collisions Of 0.6 Mev Amu⁻¹ I7+, I23+ And Au11+ Projectiles With He And Ar, W. Wolff, J. L. Shinpaugh, H. E. Wolff, Ronald E. Olson, Jee-Ching Wang, S. Lencinas, D. Piscevic, R. Herrmann, H. Schmidt-Böcking Sep 1992

Diffraction In The Binary Encounter Electron Peak Observed In Collisions Of 0.6 Mev Amu⁻¹ I7+, I23+ And Au11+ Projectiles With He And Ar, W. Wolff, J. L. Shinpaugh, H. E. Wolff, Ronald E. Olson, Jee-Ching Wang, S. Lencinas, D. Piscevic, R. Herrmann, H. Schmidt-Böcking

Physics Faculty Research & Creative Works

Relative double differential cross sections for electron emission from collisions of 0.6 MeV amu-1I7+and I23+ projectiles with Ar and Au11+projectiles with He were measured for electron energies from 100 eV to 2000 eV and for angles from 0° to 50°. Experimentally observed sudden shifts of the position of the binary encounter peak were interpreted as resulting from quantum interference in the scattering of target electrons from the partially stripped projectile ion. To this end calculations for the elastic scattering of free electrons initially at rest in the laboratory reference frame from the screened …

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Product Distributions In The Co2-Nh3-H2o System From Liquid Conductivity Measurements, James E. Pelkie, P. John Concannon, David B. Manley, Bruce E. Poling Sep 1992

Product Distributions In The Co2-Nh3-H2o System From Liquid Conductivity Measurements, James E. Pelkie, P. John Concannon, David B. Manley, Bruce E. Poling

Chemical and Biochemical Engineering Faculty Research & Creative Works

The objective of this work was to illustrate how liquid conductivity measurements could be used to provide information about the extent of ionization and the amounts of the various ionic products that are formed in the liquid phase in the CO2-NH3-H2O system. To accomplish this, pressures and liquid-phase conductivities for the CO2-NH3-H2O system were measured at 25 °C and over a range of pressures and concentrations. In order to acquire the desired information from bulk conductivity measurements, calibration curves were established from measurements with several potassium salts. These …

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In Vitro Development Of Zygotes From Prepubertal Gilts After Microinjection Of Dna, B. L. Williams, J. L. Johnson, A. E.T. Sparks, R. S. Canseco, J. W. Knight, William H. Velander, R. L. Page, W. N. Drohan, J. M. Young, R. E. Pearson, T. D. Wilkins, F. C. Gwazdauskas Jul 1992

In Vitro Development Of Zygotes From Prepubertal Gilts After Microinjection Of Dna, B. L. Williams, J. L. Johnson, A. E.T. Sparks, R. S. Canseco, J. W. Knight, William H. Velander, R. L. Page, W. N. Drohan, J. M. Young, R. E. Pearson, T. D. Wilkins, F. C. Gwazdauskas

Papers in Biotechnology

The effect of pronuclear microinjection of DNA and culture in excised mouse oviducts on the development of porcine zygotes was assessed in this study. Precocious ovulation was induced in prepubertal gilts with pregnant mare's serum gonadotrophin and hCG. Zygotes received either pronuclear microinjection of buffer alone, buffer containing a DNA construct, or no microinjection. Zygotes were cultured in vitro in either modified Krebs-Ringer bicarbonate medium (KRBI for 144 h or in mouse oviduct (MO) explant culture with KRB for 48, 72, 96, or 120 h. Pronuclear microinjection of DNA resulted in a lower (P < .05) cleavage index (CII than did buffer or no microinjection (CI 2.16 k .10 vs 2.80 f .13 and 2.93 f .lo). The CI loss was greatest for DNA-injected zygotes at the two-cell stage of development. Coculture of zygotes in MO resulted in a higher CI (P < .01) than did culture in KRB. Culture in MO for 72 h was the most beneficial system compared with MO for 48, 96, or 120 h (P < .05; CI 3.25 k .12 vs 2.66 k .18, 2.79 f .14, and 2.40 .14, respectively). Microinjection of DNA, not merely the mechanical procedure, was detrimental to early zygote development and may be the cause of low pregnancy rates.

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Some Observations Of Bispectral Behavior Of Large Ensembles Of Exact Solutions To The Burgers Equation For Random Initial Conditions, Weiguo Zheng, X. B. Reed Jan 1992

Some Observations Of Bispectral Behavior Of Large Ensembles Of Exact Solutions To The Burgers Equation For Random Initial Conditions, Weiguo Zheng, X. B. Reed

Chemical and Biochemical Engineering Faculty Research & Creative Works

Accurate bispectra for the Burgers equation have been computed into the high wave-number domain. Although only the imaginary part ib(k,l) contributes to spectral transfer, new insights having implications for three-dimensional turbulence can be gained by incorporating the real part a(k,l). For fixed l, for instance, the modulus of the bispectrum of the Burgers equation manifests a power-law subrange corresponding to the inertial subrange of the energy spectrum and an exponential subrange corresponding to the viscous cutoff of the energy spectrum. © 1992 American Institute of Physics.

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Triallylphosphine Plasma Polymerization And Reaction Of The Product With Volatile Transition Metal Compounds, S. D. Clymer, Nicholas C. Morosoff, A. L. Crumbliss Jan 1992

Triallylphosphine Plasma Polymerization And Reaction Of The Product With Volatile Transition Metal Compounds, S. D. Clymer, Nicholas C. Morosoff, A. L. Crumbliss

Chemical and Biochemical Engineering Faculty Research & Creative Works

The plasma polymerization of triallyl phosphine in order to form a crosslinked polymer thin film is described. The plasma polymer thin film has been characterized and shown to contain a high proporation of C=C and P groups conserved from the monomer. The accessibility of the phosphine groups has been demonstrated by reaction with O2, NO, Ni(CO)4, and Fe(CO)5. Reaction with O2, and NO results in a P=O moiety formation. Reaction with the gaseous metal carbonyls results in fixation of the metal via complexation by the P groups as a result of exchange …

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Preparation Of A Plasma Polymer Containing Phosphine Complexed Nickel By Concurrent Nickel Evaporation, N. (Nicholas) C. Morosoff, S. D. Clymer, A. L. Crumbliss Jan 1992

Preparation Of A Plasma Polymer Containing Phosphine Complexed Nickel By Concurrent Nickel Evaporation, N. (Nicholas) C. Morosoff, S. D. Clymer, A. L. Crumbliss

Chemical and Biochemical Engineering Faculty Research & Creative Works

This article describes one of the first examples of concurrent metal evaporation and substituted hydrocarbon plasma polymerization as a general method for preparing thin films containing a metal coordinated to a plasma polymer. In this report, the evaporation of Ni into a triallyl phosphine (TAP) glow discharge is described Deposition of a plasma polymer with concurrent reaction of Ni atoms with phosphine groups forms nickel containing triallyl phosphine plasma polymer, NiTAPPP. The chemical nature of the product is derived on the basis of infrared spectra taken of the film as formed and after reaction with air, CO, and NO. The …

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Interaction Of Sodium, Sulfur, And Silica During Coal Combustion, Thomas A. Erickson, Douglas K. Ludlow, Steven A. Benson Jul 1991

Interaction Of Sodium, Sulfur, And Silica During Coal Combustion, Thomas A. Erickson, Douglas K. Ludlow, Steven A. Benson

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Interaction of Sodium, Sulfur, and Silica at Conditions Typical in a Pulverized Coal Furnace Was Investigated by using Both Model Mixtures and a Synthetic Coal. the Model Mixtures Consisted of Selected Inorganic Constituents that Were Well Mixed in Proportions Typically Found in Low-Rank Coal. the Synthetic Coal Consisted of a Furfuryl Alcohol Polymer with Appropriate Amounts of Sodium, Sulfur, and Silica to Duplicate the Characteristics of Low-Rank Coal. the Model Mixtures and Synthetic Coal Were Burned in a Laminar Flow (Drop-Tube) Furnace at 900, 1100, 1300, and 1500 °C and Residence Times of 0.1,0.5,1.5, and 2.4 S. the Resulting …

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Network Model Investigation Of Gas Transport In Bidisperse Porous Adsorbents, John H. Petropoulos, John K. Petrou, Athanasios I. Liapis Jun 1991

Network Model Investigation Of Gas Transport In Bidisperse Porous Adsorbents, John H. Petropoulos, John K. Petrou, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

A capillary network model consisting of a micropore network permeated by one of macropores of randomly varying size has been constructed. Although simplified (to keep computer space and time requirements low) in relation to a real bidisperse porous adsorbent or catalyst, it embodies the salient pore structural features likely to determine the gas-transport behavior of such porous solids. Suitable model calculations of Knudsen gas-phase and surface diffusion enabled us to (i) validate useful approximate methods for the more economical evaluation of network permeability and (ii) demonstrate certain important characteristic effects of nonrandom bidisperse pore structure on transport behavior and their …

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Vapor-Liquid Equilibrium Data For The Nh3-H2o System And Its Description With A Modified Cubic Equation Of State, Thomas M. Smolen, David B. Manley, Bruce E. Poling Apr 1991

Vapor-Liquid Equilibrium Data For The Nh3-H2o System And Its Description With A Modified Cubic Equation Of State, Thomas M. Smolen, David B. Manley, Bruce E. Poling

Chemical and Biochemical Engineering Faculty Research & Creative Works

New pressure-temperature-overall composition vapor-liquid equilibrium (VLE) data are reported for the ammonia-water system at five temperatures between 20 and 140 °C and up to 500 pela. These data have been converted to T-P-x data, and vapor-phase compositions have been calculated by means of a Rediich-Kwong equation of state modified to Include Peneloux's volume translation and a density-dependent mixing rule. In order to achieve agreement of calculated vapor-phase compositions with previous literature results, H was necessary to use different kij values In the vapor and liquid phases. © 1991, American Chemical Society. All rights reserved.

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Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu Apr 1991

Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu

Chemical and Materials Engineering Faculty Publications

In industry there are many examples of absorption of a gas with or without chemical reaction in the liquid phase. In physical absorption, a particular gaseous component is removed from a gas mixture due to its larger solubility in the liquid phase solvent. The removal of butane and pentane from a refinery gas mixture by a heavy oil in the liquid phase is an example of physical absorption. In absorption with chemical reaction, the gaseous component to be removed transfers across the gas-liquid interface due to a difference in the bulk chemical potentials or concentrations in the two phases. The …

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Unreachable Roots For Global Homotopy Continuation Methods, Soo Hyoung Choi, Neil L. Book Jan 1991

Unreachable Roots For Global Homotopy Continuation Methods, Soo Hyoung Choi, Neil L. Book

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

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Investigation On The Use Of Ethyl Acetate As Solvent For Seed Oil Extraction, E. L. Rivera Porras Jun 1990

Investigation On The Use Of Ethyl Acetate As Solvent For Seed Oil Extraction, E. L. Rivera Porras

Tanzania Journal of Engineering and Technology (TJET)

An investigation on the use of ethyl acetate as a solvent for the seedoil industry was carried out. As hexane is the most used solvent in extraction of oil from seeds, the study focuses on the comparison of the two solvents. The parameters studied were: contact time between solvent and seed cake, temperature of the solvent, quantity of solvent used for extraction and type of solvent. The results are presented on a relative basis where hexane is given a factor of 100. From the results obtained it can be seen that ethyl acetate is in general a better solvent than …

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Enzyme- Facilitated Transport And Separation Of Organic Acids Through Liquid Membranes, David C. Rethwisch, Anuradha Subramanian, Gao Yi, Jonathan S. Dordick Jan 1990

Enzyme- Facilitated Transport And Separation Of Organic Acids Through Liquid Membranes, David C. Rethwisch, Anuradha Subramanian, Gao Yi, Jonathan S. Dordick

Papers in Biotechnology

The selective separation of organic acids is important for the production of numerous biologially functional rnuleculcs, including amino acids, peptidcs, fats, and pharmaceuticals.' Enzyme, specificalty lipases and proteases, have been used to selectively separate a variety of organic acids; however, multiple steps are usually required,Vn additiun, carbonic anhydrase has been usd in a variety of Eiquid membranes for transport of CO2.) In the present study, we have coupled the selectiviey of enzymes with liquid membranes to provide a single-step method to scicctiveiy separate and purify organic acids.

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Increased Separation By Variable-Temperature Stepwise Desorption In Multicomponent Adsorption Processes, Suvit Kulvaranon, Marshall E. Findley, Athanasios I. Liapis Jan 1990

Increased Separation By Variable-Temperature Stepwise Desorption In Multicomponent Adsorption Processes, Suvit Kulvaranon, Marshall E. Findley, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

When more components than desired are adsorbed, adsorption-desorption separation processes may not be satisfactory. However, in the cases of ethanol and water adsorption on activated carbon, propane and propylene adsorption on molecular sieves, and hydrogen sulfide, carbon dioxide, and propane adsorption on molecular sieves, it has been found that a variable-temperature stepwise desorption (VTSD) procedure following the adsorption stage can significantly increase the degree of separation achieved compared to a complete desorption of all adsorbed components. Studies indicate that these increased separations are in part due to nonequilibrium effects. An estimation of economic factors in separating low concentration propylene in …

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Effect Of Viscoplastic Flow Rules On The Initiation And Growth Of Shear Bands At High Strain Rates, R. C. Batra, Chang-Soo Kim Jan 1990

Effect Of Viscoplastic Flow Rules On The Initiation And Growth Of Shear Bands At High Strain Rates, R. C. Batra, Chang-Soo Kim

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Marchand and Duffy have reported detailed measurements of the temperature and strain as a shear band develops in a HY-100 steel. Assuming their torsional tests in thin-wall tubes can be adequately modeled by a viscoplastic block undergoing overall adiabatic simple shearing deformations, we investigate the effect of modeling the viscoplastic response of the material by a.power law, and flow rules proposed by Litonski, Bodner and Partom, and Johnson and Cook. Each of these flow rules is first calibrated by using the test data at a nominal strain-rate of 3300 s-1. Then predictions from the use of these flow rules at …

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Conformational Changes In An Epitope Localized To The Nh2-Terminal Region Of Protein C, Carolyn L. Orthener, Rapti D. Madurawe, William H. Velander, William N. Drohan, Frances D. Bettey, Dudley K. Strickhand Nov 1989

Conformational Changes In An Epitope Localized To The Nh2-Terminal Region Of Protein C, Carolyn L. Orthener, Rapti D. Madurawe, William H. Velander, William N. Drohan, Frances D. Bettey, Dudley K. Strickhand

Papers in Biotechnology

Murine monoclonal antibodies, developed following immunization with human protein C, were characterized for their ability tboin d antigen in thpe resence of either CaClz or excess EDTA. Three stablec lones were obtained which produced antiboditehsa t bound to protein C only itnh e presence of EDTA. Allt hree antibodies bound to the light choafi np rotein C on immunoblots and also bound to the homologous proteins factor X and prothrombin in solid-phase radioimmunoassays. One antibody, 7D7B10 was purified and studied further. The binding of 7D7B10 to human protein C was characterized bya KOo f 1.4 nM. In competition studies, it …

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Metabolic Activity Of Microorganisms Cultured On Inhibitory In Unsteady State, Cleophas L.C. Migiro Jun 1989

Metabolic Activity Of Microorganisms Cultured On Inhibitory In Unsteady State, Cleophas L.C. Migiro

Tanzania Journal of Engineering and Technology (TJET)

Abstract

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