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Articles 1141 - 1170 of 1407

Full-Text Articles in Biochemical and Biomolecular Engineering

Centrifugal Extraction Of Avocado Oil From The Pulp, J. W. Ntalikwa Dec 2003

Centrifugal Extraction Of Avocado Oil From The Pulp, J. W. Ntalikwa

Tanzania Journal of Engineering and Technology (TJET)

Absract

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Kinetics Of Wet Air Oxidation Of Phenol Over A Novel Catalyst, Jing Guo, Muthanna H. Al-Dahhan Oct 2003

Kinetics Of Wet Air Oxidation Of Phenol Over A Novel Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Wet Air Oxidation Kinetics of an Aqueous Solution of Phenol Was Studied over Extrudates of an Al-Fe Pillared Clay Catalyst in the Temperature Range of 90-150°C and Air Pressure Range of 0.8-2.5 MPa. the Variables Studied Included Reaction Temperature, Air Pressure, Solution PH, Initial Phenol Concentration, and Catalyst Loading. the Obtained Findings Are Compared with Those Obtained using Hydrogen Peroxide Oxidation. a Group of Kinetic Models Considering Both the Power-Law and Langmuir-Hinshelwood Approaches Was Evaluated to Describe the Catalytic Kinetics of the Phenol Disappearance. the Nonlinear Dependence of the Phenol Conversion Rate on the Catalyst Concentration Was Taken into …

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Computation Of Effectiveness Factors For Partially Wetted Catalyst Pellets Using The Method Of Fundamental Solution, E. Palmisano, P. A. Ramachandran, K. Balakrishnan, M. (Muthanna) H. Al-Dahhan Oct 2003

Computation Of Effectiveness Factors For Partially Wetted Catalyst Pellets Using The Method Of Fundamental Solution, E. Palmisano, P. A. Ramachandran, K. Balakrishnan, M. (Muthanna) H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Trickle Bed Reactors Are Widely Used in Many Process Industries. the Catalyst Particles Are Often Incompletely Wetted Especially in the Trickling Flow Regime and Hence to Design These Reactors, the Effectiveness Factor of Partially Wetted Catalyst Needs to Be Calculated Accurately. Numerical Solutions by Traditional Methods Are Time Consuming and Not Very Accurate, Especially for Some Commonly Used Complex Catalyst Shapes Such as Trilobes, Quadrilobes Etc. the Paper Presents a Novel Numerical Solution for These Problems based on the Method of Fundamental Solutions. the Advantage of the Method is that It Involves Only Boundary Collocation and Can Be Applied to …

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Preliminary Work On The Antibacterial Effect Of Strontium In Glass Ionomer Cements, A. Guida, Mark R. Towler, J. G. Wall, R. G. Hill, S. Eramo Oct 2003

Preliminary Work On The Antibacterial Effect Of Strontium In Glass Ionomer Cements, A. Guida, Mark R. Towler, J. G. Wall, R. G. Hill, S. Eramo

Chemical and Biochemical Engineering Faculty Research & Creative Works

The antibacterial effect of strontium in glass ionomer cements (GIC) was discussed. The glass transition temperatures were found to decrease with the increasing fluorine content consistent with the fluorine replacing bridging oxygens. However no significant correlation was found between the fluoride release and the antibacterial activity.

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Resolution Of Multiple Ssdna Structures In Free Solution Electrophoresis, Eve F. Fabrizio, Ali Nadim, James D. Sterling Oct 2003

Resolution Of Multiple Ssdna Structures In Free Solution Electrophoresis, Eve F. Fabrizio, Ali Nadim, James D. Sterling

Business and Information Technology Faculty Research & Creative Works

By using high concentrations of buffer, electroosmotic flow within uncoated channels of a microfluidic chip was minimized, allowing the free solution electrophoretic separation of DNA. More importantly, because of the ability to efficiently dissipate heat within these channels, field strengths as high as 600 V/cm could be applied with minimal Joule heating (< 2 °C). As a result of the higher field strengths, separations within an 8-cm-long channel were achieved within a few minutes. However, when the electrophoretic separation of single-stranded DNA (ssDNA) less than 22 bases in length was performed, containing the fluorophore Texas Red as an end label, more than the expected single peak was observed at this high electric field. On the other hand, the free solution electrophoresis of a double-stranded DNA (dsDNA) consisting of a random sequence did exhibit the expected single peak. The appearance of these multiple peaks for ssDNA is shown to be dependent upon the base content and sequence of the ssDNA as well as on the chemical structure of the fluorophore used to tag the DNA for detection. Specifically, the peaks can be attributed to different secondary structures that result either from hydrophobic interactions between the DNA bases and an uncharged fluorescent dye or from G-quadruplexes within guanine-rich strands.

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Expressions For Evaluating The Possibility Of Slip At The Liquid-Solid Interface In Open Tube Capillary Electrochromatography, B. A. Grimes, Athanasios I. Liapis Jul 2003

Expressions For Evaluating The Possibility Of Slip At The Liquid-Solid Interface In Open Tube Capillary Electrochromatography, B. A. Grimes, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this work, expressions are constructed and solved that describe the velocity field of electroosmotic flow (EOF) in open tube capillary electrochromatography (CEC) systems when the possibility of having unequal tangential velocities at the liquid-solid interface is considered and a slip condition is employed as a boundary condition for the velocity of the EOF at the capillary wall. the coupled equations of hydrodynamics (momentum balance equation) and electrostatics (Poisson equation) are solved numerically in order to obtain the distribution of the velocity field as well as the value of the volumetric flow rate in the open tube. Also, expressions for …

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Characterization And Optimization Of A Chromatographic Process Based On Ethylenediamine-N,N,N′,N′-Tetra(Methylphosphonic) Acid-Modified Zirconia Particles, Sabyasachi Sarkar, Peter W. Carr, Clayton V. Mcneff, Anuradha Subramanian Jun 2003

Characterization And Optimization Of A Chromatographic Process Based On Ethylenediamine-N,N,N′,N′-Tetra(Methylphosphonic) Acid-Modified Zirconia Particles, Sabyasachi Sarkar, Peter W. Carr, Clayton V. Mcneff, Anuradha Subramanian

Papers in Biotechnology

The primary objective of work was to characterize, optimize and model a chromatographic process based on ethylenediamine-N,N,N′,N′-tetra(methylphosphonic) acid (EDTPA)-modified zirconia particles. Zirconia particles were produced by spray-drying colloidal zirconia. Zirconia spheres produced were further classified, calcined and modified with EDTPA to yield a solid-phase support for use in bio-chromatography (r_PEZ). Specifically, the ability of r_PEZ to selectively bind and enrich IgG, IgA, and IgM from biological fluids was evaluated and demonstrated. To better understand the force of interaction between the IgG and the r_PEZ, the equilibrium disassociation constant (Kd) was determined by static binding isotherms, as a function of temperature …

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Catalytic Wet Oxidation Of Phenol By Hydrogen Peroxide Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan Jun 2003

Catalytic Wet Oxidation Of Phenol By Hydrogen Peroxide Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Extrudates of Al-Fe Pillared Clay Catalyst Suitable for Packed-Bed Operations Are Evaluated for Wastewater Treatment Via a Wet Oxidation Process Employing Hydrogen Peroxide as the Oxidant. the Reaction Was Carried Out in a Semibatch Basket Reactor under Rather Mild Conditions. Operational Parameters Were Studied under the Following Conditions: Temperature from 25 to 90 °C, Atmospheric Pressure, Initial Phenol Concentration from 100 to 2000 Ppm of the Liquid Phase, Catalyst Loading from 0 to 10 G/L, and Input H2O2 Concentration from 0.15 to 0.6 Mol/L. under These Conditions, the Al-Fe Pillared Clay Catalyst Achieves a Total Elimination of Phenol and Significant …

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Shape-Controlled Synthesis Of Iron Oxide Nanoparticles, Yangchuan Xing, T. P. Kole, J. L. Katz Jun 2003

Shape-Controlled Synthesis Of Iron Oxide Nanoparticles, Yangchuan Xing, T. P. Kole, J. L. Katz

Chemical and Biochemical Engineering Faculty Research & Creative Works

A study on shape-controlled synthesis of iron oxide nanoparticles was presented. a specially designed counterflow diffusion flame (CDF) reactor was used to synthesize the iron oxide nanoparticles. It was observed that the properties of surface atoms on the nanoparticles are associated with the chemical environments, leading to the preferential growth of a particular crystallographic surface.

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Modeling Of The Fischer-Tropsch Synthesis In Slurry Bubble Column Reactors, Novica Rados, Muthanna H. Al-Dahhan, Milorad P. Dudukovic Apr 2003

Modeling Of The Fischer-Tropsch Synthesis In Slurry Bubble Column Reactors, Novica Rados, Muthanna H. Al-Dahhan, Milorad P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

A Multicomponent One-Dimensional Dynamic Mathematical Model for the Reacting Slurry Systems with a Change in Gas Flow Rate Due to the Chemical Reaction is Developed. a Change in Gas Flow Rate Caused by the Chemical Reaction is Modeled using the overall Gas Mass Balance. Thus, All Relevant Chemical Species Are Included in the Model. Linear First-Order Reaction Kinetics is Considered. the Gas Phase is Modeled using the Two-Bubble Class Hydrodynamic Model. the Interaction between Small and Large Bubbles is Included as the Cross-Flow. Suspension of Liquid and Solids is Assumed to Form a Pseudo Slurry Phase. Back-Mixing in All of …

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Use Of Combinatorial Genetic Libraries To Humanize N-Linked Glycosylation In The Yeast Pichia Pastoris, Byung-Kwon Choi, Piotr Bobrowicz, Robert C. Davidson, Stephen R. Hamilton, David Kung, Huijuan Li, Robert Miele, Juergen Nett, Stefan Wildt, Tillman Gerngross Apr 2003

Use Of Combinatorial Genetic Libraries To Humanize N-Linked Glycosylation In The Yeast Pichia Pastoris, Byung-Kwon Choi, Piotr Bobrowicz, Robert C. Davidson, Stephen R. Hamilton, David Kung, Huijuan Li, Robert Miele, Juergen Nett, Stefan Wildt, Tillman Gerngross

Dartmouth Scholarship

The secretory pathway of Pichia pastoris was genetically re-engineered to perform sequential glycosylation reactions that mimic early processing of N-glycans in humans and other higher mammals. After eliminating nonhuman glycosylation by deleting the initiating alpha-1,6-mannosyltransferase gene from P. pastoris, several combinatorial genetic libraries were constructed to localize active alpha-1,2-mannosidase and human beta-1,2-N-acetylglucosaminyltransferase I (GnTI) in the secretory pathway. First, >32 N-terminal leader sequences of fungal type II membrane proteins were cloned to generate a leader library. Two additional libraries encoding catalytic domains of alpha-1,2-mannosidases and GnTI from mammals, insects, amphibians, worms, and fungi were cloned to generate catalytic domain libraries. …

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Investigation Into The Ultrasound Setting Of Glass Ionomer Cements. Part I. Postulated Modalities, Mark R. Towler, C. M. Crowley, R. G. Hill Apr 2003

Investigation Into The Ultrasound Setting Of Glass Ionomer Cements. Part I. Postulated Modalities, Mark R. Towler, C. M. Crowley, R. G. Hill

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fuji IX glass is a low phosphate, low soda containing glass which has strontia incorporated as a radio-pacifier. This glass material was analyzed during exposure to different durations of ultrasound in an attempt to determine how the glass phase reacts. Cross sections of Fuji IX cement, set both conventionally and by ultrasound, were subsequently compared by microscopy. The resultant data were analyzed in detail.

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Transgenic Non-Human Mammals Expressing Human Coagulation Factor Viii And Von Willebrand Factor, Henryk Lubon, William N. Drohan, William H. Velander Feb 2003

Transgenic Non-Human Mammals Expressing Human Coagulation Factor Viii And Von Willebrand Factor, Henryk Lubon, William N. Drohan, William H. Velander

Papers in Biotechnology

A non-human transgenic mammalian animal, as described above, contains an exogenous double stranded DNA sequence stably integrated into the genome of the animal, which comprises cis-acting regulatory units operably linked to a DNA sequence encoding human Factor VIII protein and a signal peptide, where the cis-acting regulatory units are active in mammary gland cells and the signal peptide is active in directing newly expressed Factor VIII into the milk of the animal. The promoter may be a milk protein promoter such as for whey acidic protein, casein, lactalbumin, or beta-lactoglobulin promoter. The transgenic mammals are preferably farm animals, for example, …

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Pichia Pastoris Fermentation With Mixed-Feeds Of Glycerol And Methanol: Growth Kinetics And Production Improvement, Wenhui Zhang, Karen J. Hywood Potter, Bradley A. Plantz, Vicki L. Schlegel, Leonard A. Smith, Michael M. Meagher Jan 2003

Pichia Pastoris Fermentation With Mixed-Feeds Of Glycerol And Methanol: Growth Kinetics And Production Improvement, Wenhui Zhang, Karen J. Hywood Potter, Bradley A. Plantz, Vicki L. Schlegel, Leonard A. Smith, Michael M. Meagher

Papers in Biochemical Engineering

Fed-batch fermentation of a methanol utilization plus (Mut+) Pichia pastoris strain typically has a growth phase followed by a production phase (induction phase). In the growth phase glycerol is usually used as carbon for cell growth while in the production phase methanol serves as both inducer and carbon source for recombinant protein expression. Some researchers employed a mixed glycerol-methanol feeding strategy during the induction phase to improve production, but growth kinetics on glycerol and methanol and the interaction between them were not reported. The objective of this paper is to optimize the mixed feeding strategy based on growth kinetic studies …

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Sequence Dependent Mobility Of Short Oligonucleotides In Free-Solution Electrophoresis, James D. Sterling, Eve F. Fabrizio, Ali Nadim Jan 2003

Sequence Dependent Mobility Of Short Oligonucleotides In Free-Solution Electrophoresis, James D. Sterling, Eve F. Fabrizio, Ali Nadim

Business and Information Technology Faculty Research & Creative Works

No abstract provided.

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Bubble Dynamics Measurements Using Four-Point Optical Probe, Junli Xue, Muthanna H. Al-Dahhan, M. P. Dudukovic, R. F. Mudde Jan 2003

Bubble Dynamics Measurements Using Four-Point Optical Probe, Junli Xue, Muthanna H. Al-Dahhan, M. P. Dudukovic, R. F. Mudde

Chemical and Biochemical Engineering Faculty Research & Creative Works

By Conducting an Analysis of the Measurement Errors It Was Found that Bubble Dynamics Obtained by Two-Point Probes Can Be Highly Inaccurate. a Four-Point Optical Probe with Appropriate Data Processing Algorithm Has Been Developed So that the Bubble Velocity Vector Can Be Obtained. This Probe Provides Directly the Value of Specific Gas-Liquid Interfacial Area. However, for Obtaining Accurate Values of Bubble Velocity and Size, the Four-Point Probe Must Be Calibrated by a CCD Camera at the Same Conditions. Calibration Columns Have Been Developed for This Purpose Where the Bubble Size and Velocity Can Be Varied to Calibrate the Measurements by …

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Analysis Of Photobioreactors For Culturing High-Value Microalgae And Cyanobacteria Via An Advanced Diagnostic Technique: Carpt, Hu Ping Luo, Abdenour Kemoun, Muthanna H. Al-Dahhan, J. M.Fernández Sevilla, J. L.García Sánchez, F. García Camacho, E. Molina Grima Jan 2003

Analysis Of Photobioreactors For Culturing High-Value Microalgae And Cyanobacteria Via An Advanced Diagnostic Technique: Carpt, Hu Ping Luo, Abdenour Kemoun, Muthanna H. Al-Dahhan, J. M.Fernández Sevilla, J. L.García Sánchez, F. García Camacho, E. Molina Grima

Chemical and Biochemical Engineering Faculty Research & Creative Works

Photosynthetic Algal Cultures Are a Potential Source of Many High-Value Products. in Photobioreactors (PBR), the Availability and the Intensity of the Light, Which Are Affected by the Cells' Movement, Are the Major Factors Controlling the Biomass Productivity. Hydrodynamics, Hence, Play a Significant Role in the Reactor's Performance, as They Determine Not Only the Flow Field, I.e. Liquid Flow and Mixing, Shear Stresses, Etc., But Also the Movements of the Cells. in This Work, Computer-Automated Radioactive Particle Tracking (CARPT) Technique Was Employed to Evaluate its Feasibility for Characterizing PBRs. Liquid Velocity Profiles, Cells' Movement, and the Temporal Irradiance Patterns Obtained by …

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Computer Simulations And Neutron Reflectivity Of Proteins At Interfaces, Amol A. Mungikar, Daniel Forciniti Dec 2002

Computer Simulations And Neutron Reflectivity Of Proteins At Interfaces, Amol A. Mungikar, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Computer simulations in conjunction with neutron reflectivity is an excellent combination for the study of biological materials at solid-liquid interfaces: Both techniques have excellent resolution levels (Ångströms) and they are mature. A stronger interaction between physicists and biologists will allow the use of these two approaches in topics of biological-biomedical interest.

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Novel General Expressions That Describe The Behavior Of The Height Equivalent Of A Theoretical Plate In Chromatographic Systems Involving Electrically-Driven And Pressure-Driven Flows, B. A. Grimes, S. Lüdtke, K. K. Unger, Athanasios I. Liapis Dec 2002

Novel General Expressions That Describe The Behavior Of The Height Equivalent Of A Theoretical Plate In Chromatographic Systems Involving Electrically-Driven And Pressure-Driven Flows, B. A. Grimes, S. Lüdtke, K. K. Unger, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

Novel general expressions are constructed and presented that describe the behavior of the height equivalent of a theoretical plate (plate height), H, as a function of the linear velocity, Vx, along the axis, x, of the column and the kinetic parameters that characterize the mass transfer and adsorption mechanisms in chromatographic columns. Open tube capillaries as well as columns packed with either non-porous or porous particles are studied. The porous particles could have unimodal or bimodal pore-size distributions and intraparticle convective fluid flow and pore diffusion are considered. The expressions for the plate height, H, presented in this work could …

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The Evolution And Implications Of The Concentration Profiles Of An Analyte In Porous Adsorbent Particles Packed In A Capillary Electrochromatography Column Operated In The Analytical Mode, B. A. Grimes, Athanasios I. Liapis Dec 2002

The Evolution And Implications Of The Concentration Profiles Of An Analyte In Porous Adsorbent Particles Packed In A Capillary Electrochromatography Column Operated In The Analytical Mode, B. A. Grimes, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this work, a mathematical model is constructed and solved to describe the propagation and dispersion of the mass wave of an analyte in a capillary electrochromatography (CEC) column packed with porous adsorbent particles and operated in the analytical mode. The evolution and dynamic behavior of the isoconcentration contours of the concentration of the analyte in the pores of the particles are presented in order to demonstrate the significant impact that the velocity of the intraparticle electroosmotic flow (EOF) encountered in CEC systems could have in reducing the overall intraparticle mass transfer resistance. It is shown that under both unretained …

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Method, Apparatus And Article For Microfluidic Control Via Electrowetting, For Chemical, Biochemical And Biological Assays And The Like, James D. Sterling Nov 2002

Method, Apparatus And Article For Microfluidic Control Via Electrowetting, For Chemical, Biochemical And Biological Assays And The Like, James D. Sterling

Business and Information Technology Faculty Research & Creative Works

An active-matrix microfluidic platform employs thin film transistor active ("TFT") matrix liquid crystal display ~ technology to manipulate small samples of fluid for chemical, biochemical, or biological assays without moving parts, for example, using a two-dimensional matrix array of drive electrodes. The active-matrix microfluidic platform may employ existing active matrix 0 addressing schemes and/or commercial "off-the-shelf" animation software to program assay protocols. A feedback subsystem may > determine an actual location of a fluid in the microfluidic structure, and provides location information to for display, for example, on an active-matrix display, and/or to control movement of one or more fluid bodies …

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An Approach To Sequence Dna Without Tagging, Sanjun Niu, Ravi F. Saraf Sep 2002

An Approach To Sequence Dna Without Tagging, Sanjun Niu, Ravi F. Saraf

Papers in Biotechnology

Microarray technology is playing an increasingly important role in biology and medicine and its application to genomics for gene expression analysis has already reached the market with a variety of commercially available instruments. In these combinatorial analysis methods, known probe single-strand DNA (ssDNA) ‘primers’ are attached in clusters of typically 100 μm × 100 μm pixels. Each pixel of the array has a slightly different sequence. On exposure to ‘unknown’ target ssDNA, the pixels with the right complementary probe ssDNA sequence convert to double-stranded DNA (dsDNA) by a hybridization reaction. To transduct the conversion of the pixel to dsDNA, the …

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Microbial Cellulose Utilization: Fundamentals And Biotechnology, Lee R. Lynd, Paul J. Weimer, Willem H. Van Zyl, Isak S. Pretorius Sep 2002

Microbial Cellulose Utilization: Fundamentals And Biotechnology, Lee R. Lynd, Paul J. Weimer, Willem H. Van Zyl, Isak S. Pretorius

Dartmouth Scholarship

Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for cellulose-grown continuous cultures. Quantitative description of cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of microbial …

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Fluoride Release From Model Glass Ionomer Cements, A. Guida, R. G. Hill, Mark R. Towler, S. Eramo Jul 2002

Fluoride Release From Model Glass Ionomer Cements, A. Guida, R. G. Hill, Mark R. Towler, S. Eramo

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass ionomer cements (GICs) are an important class of biomedical material used extensively for color matched mercury free, dental restorations. GICs can release clinically beneficial amounts of fluoride and have acceptable handling properties which make them suitable as dental restoratives. The fluoride release of model GICs produced from specially synthesized fluoro-alumino-silicate glasses was studied. Nine glasses of varying fluoride content based on 4.5SiO2-3Al2O3-1.5P2O5-(5-Z)CaO-ZCaF2 were synthesized, and cement disks were prepared from them. The glass transition temperature reduced with increasing fluorine content of the glass. Fluoride ion release was measured …

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A Preliminary Study Of An Aluminum-Free Glass Polyalkenoate Cement, Mark R. Towler, C. M. Crowley, D. Murphy, A. M.C. O'Callaghan Jul 2002

A Preliminary Study Of An Aluminum-Free Glass Polyalkenoate Cement, Mark R. Towler, C. M. Crowley, D. Murphy, A. M.C. O'Callaghan

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

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Cfd Of Multiphase Flow In Packed-Bed Reactors: Ii. Results And Applications, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic Apr 2002

Cfd Of Multiphase Flow In Packed-Bed Reactors: Ii. Results And Applications, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Numerical Simulations of Multiphase Flow using the K-Fluid CFD Model Described in Part I of This Issue Are Presented for Packed Beds at Various Operating Conditions. Both Steady-State and Unsteady-State (E.g., Periodic Operation) Feed Conditions Were Studied Numerically. Predictions of the K-Fluid CFD Model Are Comparable with the Experimental Data in the Literature for Liquid Upflow in a Cylindrical Packed Bed. in Addition to the Mean Porosity and the Longitudinally Averaged Radial Porosity Profile, the Variance of the Porosity Distribution is Needed for Predicting the Probability Density Function of the Sectional Flow Velocity. in the Trickling Flow Regime, the K-Fluid …

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Cfd Of Multiphase Flow In Packed-Bed Reactors: I. K-Fluid Modeling Issues, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic Apr 2002

Cfd Of Multiphase Flow In Packed-Bed Reactors: I. K-Fluid Modeling Issues, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Eulerian K-Fluid CFD Model Was Used to Simulate the Macroscale Multiphase Flow in Packed Beds. the Geometric Complexity of the Bed Structure is Resolved by Statistically Describing the Porosity Distribution. the Complicated Multiphase Interactions Are Computed using the Ergun Type of Formula Developed based on Bench-Scale Hydrodynamic Experiments. the Work is Presented in Two Sequential Articles. Part I Discusses Implementation Issues of the K-Fluid CFD Model for Packed Beds. the Drag Exchange Coefficients Are Obtained from the Model of Holub Et Al. for the Particle-Fluid Interfaces Xks and from the Model of Attou Et Al. (1999) for the Gas …

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Ethylene Oxide And Propylene Oxide Random Copolymer/Sodium Chloride Aqueous Two-Phase Systems: Wetting And Adsorption On Dodecyl-Agarose And Polystyrene, Yingqing Huang, Daniel Forciniti Mar 2002

Ethylene Oxide And Propylene Oxide Random Copolymer/Sodium Chloride Aqueous Two-Phase Systems: Wetting And Adsorption On Dodecyl-Agarose And Polystyrene, Yingqing Huang, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Liquid/liquid partition chromatography is a mild yet powerful separation method for a variety of biological materials. This work demonstrates that it should be feasible to immobilize an ethylene oxide-propylene oxide (EO/PO) random copolymer solution and to use a solution of NaCl equilibrated against the polymer solution as the mobile-phase (poly (EO-PO) [P(EO-PO)] and NaCl form two aqueous phases known as aqueous two-phase systems). Three random copolymers with different molecular weights and EO/PO ratios were used. Dodecyl-agarose and polystyrene were tested as possible supports. The wetting energies of the aqueous two-phase systems on these two kinds of surfaces were calculated as …

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Thermal Analysis Of Fly Ashes Sourced From European Non-Blended Coals, Kenneth T. Stanton, Mark R. Towler, Patrick Mooney, Robert G. Hill, Xavier Querol Mar 2002

Thermal Analysis Of Fly Ashes Sourced From European Non-Blended Coals, Kenneth T. Stanton, Mark R. Towler, Patrick Mooney, Robert G. Hill, Xavier Querol

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fly ashes exist as a mixture of major amorphous phases and minor crystalline phases. For commercial applications, such as in concretes and for the production of zeolites, it would be desirable to be able to predict the reactivity of fly ashes. The amorphous phase dominates degradation behaviour, because glasses have a higher potential energy than the equivalent crystal structure and the variation of bond angles and distances in a glass make the bond breakage easier. Despite the large quantities of fly ash produced annually by coal-burning power plants, there have been very few studies investigating the microstructure and composition of …

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Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler Mar 2002

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …

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