Chemical Engineering Commons^™

A Macroscopic Kinetic Model For Dna Polymerase Elongation And High-Fidelity Nucleotide Election, Steve Viljoen, Mark A. Griep, Michael Nelson, Hendrik J. Viljoen

Papers in Enzyme Kinetics

The enzymatically catalyzed template-directed extension of ssDNA/primer complex is an impor-tant reaction of extraordinary complexity. The DNA polymerase does not merely facilitate the insertion of dNMP, but it also performs rapid screening of substrates to ensure a high degree of fidelity. Several kinetic studies have determined rate constants and equilibrium constants for the elementary steps that make up the overall pathway. The information is used to develop a macro-scopic kinetic model, using an approach described by Ninio [Ninio J., 1987. Alternative to the steady-state method: derivation of reaction rates from first-passage times and pathway probabili-ties. Proc. Natl. Acad. Sci. U.S.A. …

Catalytic Wet Air Oxidation Of Phenol In Concurrent Downflow And Upflow Packed-Bed Reactors Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

An Experimental Study is Presented for Comparing the Behavior of a Packed Bed Reactor in the Catalytic Liquid-Phase Oxidation of Aqueous Phenol with Two Modes of Operation, Downflow and Upflow. the Operating Parameters Investigated Included Temperature, Reactor Pressure, Gas Flowrate, Liquid Hourly Space Velocity and Feed Concentration. Because of the Completely Wetted Catalyst, the Upflow Reactor Generally Performs Better for High Pressures and Low Feed Concentrations When the Liquid Reactant Limitation Controls the Rate. the Interaction between the Reactor Hydrodynamics, Mass Transfer, and Reaction Kinetics is Discussed. for Both Operation Modes, Complete Phenol Removal and Significant Total Organic Carbon (TOC) …

Crystalization Studies In Hollow Fiber Devices, Dimitrios Zarkadas

Dissertations

Crystallization was examined under a new perspective and in a flow environment much different from that available in currently used industrial devices. Three crystallization techniques were tested in the unique flow environment offered by hollow fiber devices. In addition, a new type of heat exchanger based on hollow fibers was tested as well as the potential use of porous hollow fiber devices as mixing devices. Hollow fiber devices are compact, extremely efficient on a volumetric basis, easy to scale up and control and their inherent characteristics promote the creation of homogeneous temperature and concentration conditions on a scale considerably smaller …

Fractionation Of Cell Mixtures Using Acoustic And Laminar Flow Fields, Manoj Kumar, Donald L. Feke, Joanne M. Belovich

Chemical & Biomedical Engineering Faculty Publications

A fractionation method applicable to different populations of cells in a suspension is reported. The separation was accomplished by subjecting the suspension to a resonant ultrasonic field and a laminar flow field propagating in orthogonal directions within a thin, rectangular chamber. Steady, laminar flow transports the cell suspension along the chamber, while the ultrasonic field causes the suspended cells to migrate to the mid-plane of the chamber at rates related to their size and physical properties. A thin flow splitter positioned near the outlet divides the effluent cell suspension into two product streams, thereby allowing cells that respond faster to …

Comprehensive Black Liquor Droplet Combustion Studies, Leong-Teng Ip

Theses and Dissertations

Black liquor, a byproduct from pulp production, is burned in a recovery boiler to generate electricity and recover inorganic materials. Black-liquor-droplet combustion is fundamental to understanding and potentially improving recovery boiler performance. This investigation reports comprehensive experimental data collected for a suite of five liquors. All the data were collected with newly-designed laboratory equipment, several aspects of which are unique. Single droplets were suspended on a thermocouple and heated in a furnace. Simultaneous diameter (size and shape), internal and surface temperatures, surface emissivity, and mass were measured under various furnace temperatures and gas compositions. The images recorded by the cameras …

Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander

Papers in Biotechnology

Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1 kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the Aα,Bβ and γ fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 μg/ml, with total secretion of subunits approaching 700 μ g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. …

Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander

Papers in Biotechnology

Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1 kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the Aα,Bβ and γ fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 μg/ml, with total secretion of subunits approaching 700 μ g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. …

The Grain Size And Microstructure Of Jet-Electroplated Damascene Copper Films, Stacy H. Gleixner, Andrew Tzanavaras, Gregory Young

Faculty Publications

Electroplated damascene copper is rapidly replacing aluminum-copper alloys for on-chip interconnect metallization in advanced ultralarge scale integrated (ULSI) semiconductor devices. In addition to a high degree of (111) crystallographic texture, large defect-free grains are desired to enhance the performance and reliability of copper interconnects in such devices. The brightening additive level and dc current density of electroplating baths are two parameters that affect the process gap-filling capability and the degree of additive incorporation in these copper films. Additive incorporation can inhibit grain growth during the room-temperature recrystallization process and therefore affect the final grain size in electroplated copper films. This …

Use Of Calcium Hypochlorite As A Sanitizer For Seeds Used For Sprouting: Task #2; Impact: Improved Alfalfa Decontamination Technologies, Emily Damron, Carrie Klein, Melissa Leach, Jordan Mourot, Tom Murphy, Amy Seamans, Ryan Wilson

Inquiry: The University of Arkansas Undergraduate Research Journal

Consumption of raw or lightly cooked alfalfa sprouts has been a concern of the U.S. Food and Drug Administration (FDA) in recent years due to connections between sprouts and foodborne illnesses. Researchers have identified, contaminated seeds as the primary source of alfalfa sprouts contamination. Contamination of alfalfa seeds can originate in the field, harvesting, storing, or sprouting. Two pathogens of particular concern on alfalfa seeds are Escherichia coli 0157:H7 (E. coli) and Salmonella. These pathogens are capable of producing biofilms that provide protection for individual cells and allow for survival in otherwise hostile environments, including some disinfectant washes. Other factors …

Preparation And Evaluation Of The Electrospun Chitosan/Peo Fibers For Potential Applications In Cartilage Tissue Engineering, Anuradha Subramanian, David Vu, Gustavo F. Larsen, Hsin Yii Lin

Papers in Biotechnology

Fibrous materials have morphological similarities to natural cartilage extracellular matrix and have been considered as candidate for bone tissue engineering scaffolds. In this study, we have evaluated a novel electrospun chitosan mat composed of oriented sub-micron fibers for its tensile property and biocompatibility with chondrocytes (cell attachment, proliferation and viability). Scanning electronic microscope images showed the fibers in the electrospun chitosan mats were indeed aligned and there was a slight cross-linking between the parent fibers. The electrospun mats have significantly higher elastic modulus (2.25 MPa) than the cast films (1.19 MPa). Viability of cells on the electrospun mat was 69% …

A Simple Extrusion Method For The Synthesis Of Aligned Silica Nanowires Using The Template Of A Rigid Surface Mesophase, Limin Liu, Grace Tan, Vivek Agarwal, Arijit Bose, Jibao He, Gary L. Mcpherson, Vijay T. John

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Long range alignment of silica nanowires has been accomplished by extrusion of a novel surfactant mesophase prior to silica synthesis.

Electrodeposition Of Auco Alloys And Multilayers, Maoshi Guan

LSU Master's Theses

Electrodeposited AuCo and Au/Co multilayers are of interest as potential materials for MEMS components. AuCo alloys have been fabricated by the electrodeposition technique, but from cyanide-containing electrolyte. In this study, we explored the electrodeposition of AuCo and Au/Co multilayer thin films, and nanowires, from a non-cyanide electrolyte. Two variables were considered: the concentration of citric acid and pH. The changes in composition were described by the differences in the partial current densities. The effect of pH and citric acid concentration on the deposit composition and current efficiency was investigated. Results showed that a lower citric acid concentration was favored for …

Relationship Between The Extent Of Non-Viable Myocardium And Regional Left Ventricular Function In Chronic Ischemic Heart Disease, Arunark Kolipaka, George P. Chatzimavroudis, Richard D. White, Michael L. Lieber, Randolph M. Setser

Chemical & Biomedical Engineering Faculty Publications

Purpose. To define the relationship between left ventricular (LV) regional contractile function and the extent of myocardial scar in patients with chronic ischemic heart disease and multi-vessel coronary artery disease. Methods. Twenty-three patients with chronic ischemic heart disease and 5 healthy volunteers underwent magnetic resonance imaging (MRI). In patients, the relative area ( Percent Scar) and transmural extent (Transmurality) of myocardial infarction were computed from short-axis delayed enhancement images. In each image, myocardial segments were categorized based on the extent of infarction they contained, with 6 categories each for Percent Scar and Transmurality: normal, from healthy volunteers; and 0%; 1–25%, …

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System: Quarterly Report, Kenneth Czerwinski, Cynthia-May Gong, Amber Wright

Separations Campaign (TRP)

The speciation of hexavalent U and tetravalent Pu will be examined in the TBPdodecane- nitric acid systems. This topic is chosen based on data needs for separation modeling identified by the AFCI. Emphasis will be placed on studying the influence of nitrate and acetohydroxamic acid on U and Pu speciation as well as conditions where a third phase forms in the organic phase. The organic phase will be 30 % TBP in dodecane. Equal volumes of aqueous and organic phase will be used. The speciation of the actinides in the aqueous and organic phase will be determined by a number …

Large Pyroelectric Response From Reactively Sputtered Aluminum Nitride Thin Films, Everett E. Crisman, John S. Derov, Alvin J. Drehman, Otto J. Gregory

Chemical, Biomolecular, and Materials Engineering Faculty Publications

We report the pyroelectric response of c-axis oriented, undoped, wurtzite, aluminum nitride reactively sputtered onto polished silicon wafers. The voltage between a metallic contact on the AlN surface and the n⁺ -doped silicon substrate was monitored during pulsed infrared, radiant heating. From analysis of the data, a pyroelectric voltage coefficient, P_V, in excess of 0.5 x 10⁶ V/m/K was extracted for films in the 600 to 2500 Å thickness range.

Swelling Properties And Intrinsic Reactivities Of Coal Chars Produced At Elevated Pressures And High Heating Rates, Dong Zeng, Michael Clark, Todd Gunderson, William C. Hecker, Thomas H. Fletcher

Faculty Publications

A high-temperature, high-pressure flat-flame burner reactor was developed to prepare char at different pressures. This system achieves particle heating rates of 10⁵ K/s, which better mimics industrial conditions than conventional drop tube or radiative flow reactors. Previous data at atmospheric pressure demonstrated a significant decrease in particle swelling during devolatilization as heating rates increased from 10⁴ K/s (the typical drop tube heating rate) to 10⁵ K/s. Pyrolysis experiments were performed at pressures from 1 to 15 atm at 1300 C for two bituminous coals and a lignite. Average swelling was determined from a combination of the mass …

Pervaporation Of Water From Solvent Solutions, Richard Manning

Theses

Pervaporation is an emerging membrane technology which has found acceptance as a method for the dehydration of organic solvents.

An existing pervaporation apparatus was modified to accommodate a new type of pervaporation membrane. The instrumentation used with the pervaporation apparatus was upgraded to include a Keithley Data Logger. A HAZOP was carried out on the modified pervaporation apparatus to ensure the apparatus was safe to operate after the modifications were completed.

The pervaporation apparatus was initially tested using screening experiments to verify that changing the operating parameters produced a measurable response which could be recorded. The pervaporation apparatus was successfully …

Data Management And Visualization Of X-Ray Diffraction Spectra From Thin Film Ternary Composition Spreads, I. Takeuchi, C. J. Long, O. O. Famodu, M. Murakami, Jason R. Hattrick-Simpers, G. W. Rubloff, M. Stukowski, K. Rajan

Faculty Publications

We discuss techniques for managing and visualizing x-ray diffraction spectrum data for thin film composition spreads which map large fractions of ternary compositional phase diagrams. An in-house x-ray microdiffractometer is used to obtain spectra from over 500 different compositions on an individual spread. The MATLAB software is used to quickly organize the data and create various plots from which one can quickly grasp different information regarding structural and phase changes across the composition spreads. Such exercises are valuable in rapidly assessing the “overall” picture of the structural evolution across phase diagrams before focusing in on specific composition regions for detailed …

Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason R. Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. L. Wang, J. P. Liu, S. E. Lofland, Somdev Tyagi, J. W. Freeland, D. Giubertoni, M. Bersani, M. Anderle

Faculty Publications

We have fabricated Fe∕Sm–Co bilayers with gradient Fe thicknesses in order to systematically study the dependence of exchange coupling on the thickness of the Fe layer. The Fe layer was deposited at two different temperatures (150 and 300°C) to study the effect of deposition temperature on the exchange coupling. Magneto-optical Kerr effect and x-ray magnetic circular dichroism (XMCD) have been employed as nondestructive rapid characterization tools to map the magnetic properties of the gradient samples. Systematic enhancement in exchange coupling between the soft layer and the hard layer is observed as the soft layer thickness is decreased. Separate exchange couplings …

An In-Situ Capping Design For The Remediation Of Petroleum Contaminated Sediments, Melanie Krystle Harris

LSU Master's Theses

Historical disposal practices used by oil companies have caused the accumulation of contaminated sediments in their nearby lakes and ponds. These companies are now faced with the challenge of remediating the bodies of water that contain these contaminated sediments. The contaminants that remain in the sediment continue to pose a threat to human health and the environment. For example, high concentrations of polycyclic aromatic hydrocarbons (PAHs), which are still present in the bottom sediments can have toxic effects on aquatic life. One form of remediation for this problem is In-Situ Capping (ISC), which is defined as a method whereby material …

Development And Model Formulation Of Scalable Carbon Nanotube Processes: Hipco And Comocat Process Models, Adedeji Ebenezer Agboola

LSU Master's Theses

Carbon nanotubes are seamless cylindrical tubes, consisting of carbon atoms arranged in a regular hexagonal structure. It is considered as the ultimate engineering material because of its unique and distinct electronic, mechanical and material characteristics. The discovery of these materials pioneered the nanotechnology revolution, which encompasses a broad and multidisciplinary spectrum, including nanomaterials, nanobiotechnology, and nanoelectronics. Hundreds of published articles of laboratory scale and pilot plant processes were reviewed that describe potential synthesis and post–synthesis purification methods for large scale production of carbon nanotubes. The main production technologies include electric arc discharge, laser vaporization, and catalytic chemical vapor deposition. These …

Simulation And Economic Evaluation Of Coal Gasification With Sets Reforming Process For Power Production, Zachary Hoffman

LSU Master's Theses

Increasing natural gas prices have raised interest in alternate energy resources. Popular belief in the connection between carbon dioxide emissions and global warming has motivated the search for a technique to isolate carbon dioxide from combustion stack gases. Coal gasification with SETS reforming has been proposed as a solution to both of these issues in that it provides an alternate energy source and 100% carbon dioxide sequestration. The purpose of this research is to simulate this process using AspenPlus to perform the rigorous material and energy balances. The results of this simulation are used to carry out a complete economic …

Controlled High Pressure Slurry Injection In Water Jetting Applications-A New Approach, Manish Kumar

LSU Master's Theses

The ability of an abrasive assisted water jet to cut through rocks and metals has potential applications in the oilfield. However, the size of cutting nozzle has not allowed water jet to be used on commercial scale for drilling reservoir rocks down-hole. Inefficient momentum transfer to abrasive particles from pressurized water and lack of abrasive feed rate control in commercially available units has further discouraged the use of water jet in oil industry. Despite various technical difficulties, immense power of water jet cannot be neglected. Studies have shown that momentum transfer can be improved significantly, if abrasive particles are introduced …

Thermo And Kinetic Studies On The Sorption And Desorption Of Hydrophobic Organic Contaminants In Sediments, Yunzhou Chai

LSU Doctoral Dissertations

This study investigated the correlation of desorption resistance of hydrophobic organic contaminants (HOCs) in sediment and the heterogeneity of sediment organic matter (SOM). The amorphous and condensed phase organic carbon contents were defined by the method of Gustafsson et al. (1997) using thermal oxidation of sediment under 375°C. The desorption-resistant fraction of contaminants in sediments was operationally defined as the fraction that could not be removed by the adsorbent XAD-2. The correlation of the desorption-resistant fraction with sediment organic carbon characteristics was evaluated for both laboratory-inoculated and field-contaminated sediments. No strong correlation between the desorption resistant fraction in laboratory-inoculated sediments …

Characterization Of Fluoropolymer Powders Made By Supercritical Assisted Mixing With Crystalline Additives, Ntoh Atem-Tambe

Theses and Dissertations

This research project investigates a new technique to efficiently mix crystalline solid additives with polymers by gentle ball milling with steel balls in the presence of carbon dioxide (C02) at 17 to 30°C and 1300 to 2500 psig. As the ball milling system is agitated, the steel balls transfer mechanical energy to the fluoropolymer and additive thereby converting them to powders. C02 is added into the chamber to expand the polymer and make it amenable to impregnation by the additive. At the end of the mixing process, a free flowing powder is produced consisting of the additive coated with fluoropolymer. …

Halonitromethane Treatment Using Advanced Oxidation Process: Rates, Mechanisms And Kinetic Modeling, Stuart Kirkham Cole

Civil & Environmental Engineering Theses & Dissertations

Halonitromethanes (HNMs) are low molecular weight halogenated disinfection-by-products (DBPs) found to be formed during ozonation, chlorination, or chloramination of waters containing natural bromide ion and nitrogenous organic matter. This work identifies the absolute rate constants for the oxidative hydroxyl radical (•OH) and reductive hydrated electron e^- _aq extinction of HNM compounds. Three forms of HNMs included in this study are the chlorinated, brominated, and mixed halogenated compounds. Electron pulse radiolysis and transient absorption spectroscopy were used to measure •OH and e^- _aq radical absolute reaction rate constants for a total of nine HNMs. To elucidate the decomposition reaction …

Results Of An Interlaboratory Study Of The Astm Standard Test Method For Tensile Properties Of Polymer Matrix Composites D 3039, Margaret Pinnell, Richard Fields, Ronald Zabora

Mechanical and Aerospace Engineering Faculty Publications

An investigation was conducted on the ASTM Standard Test Method for Tensile Properties of Polymer Matrix Composites (D 3039). This investigation consisted of both preliminary testing and an interlaboratory test program. Information generated from preliminary testing was used to determine the effects of various parameters and to optimize the interlaboratory test plan and test protocol. The interlaboratory study portion of this investigation was conducted on six composite material systems in a variety of lay-up configurations. The number of participating labs ranged from five to nine depending on the material type. Precision statistics were determined for the ASTM D 3039 standard …

Modeling Of Chemical Fate And Transport In The Environment, Andre Marquette

LSU Master's Theses

The Environmental Engineering discipline remains on the forefront of discovery due to advancements in computer technology, advancements in experimental methods and an ever increasing public interest in mitigating the harmful effects of the chemical process industry. Experimental methods have a critical role in defining environmental processes and effects but are limited in their ability to predict future environmental conditions. Conceptual and mathematical models are needed in order to evaluate the effect of environmental conditions far into the future as well as to extend and apply the knowledge gained from experimentation. Models can be used to predict chemical exposure levels, design …

Physical Model Experiments Of The Gas-Assisted Gravity Drainage Process, Amit P. Sharma

LSU Master's Theses

The displacement of oil by gas injection in oil reservoirs is an attractive method of improved oil recovery. Commercial gravity-stable gas injection projects have demonstrated excellent recoveries; however, their application has been limited to dipping reservoirs and pinnacle reefs. Horizontal gas floods and the water alternating gas (WAG) processes, practiced in horizontal type reservoirs, have yielded less than satisfactory recoveries of 5-10%. The Gas Assisted Gravity Drainage (GAGD) Process being developed at LSU extends the concept of gravity-stable gas floods to horizontal type reservoirs to improve volumetric sweep and oil recovery. This experimental study consists of a series of visual …

Relative Permeability And Wettability Implications Of Dilute Surfactants At Reservoir Conditions, Ayodeji Adebola Abe

LSU Master's Theses

The improvement or increase of oil recoverable from discovered reservoirs has always been a very important issue as this helps to meet ever growing energy demand. Several methods have been put forward as means of achieving this objective. Chemical flooding, using surfactants has been considered in enhanced oil recovery processes. Surfactants are used primarily to lower oil-water interfacial tension (IFT) and thus improve production. However, surfactants possess the ability to alter rock wettability and hence increase oil production. Previous investigations were performed at ambient conditions using stocktank oil. Extrapolation of the findings from the ambient conditions testing to reservoir conditions …