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Articles 10891 - 10920 of 14130

Full-Text Articles in Engineering

Dynamic Sulfur Tolerant Process And System With Inline Acid Gas-Selective Removal For Generating Hydrogen For Fuel Cells, Surjit Randhava, W. S. Winston Ho, Richard L. Kao, Elias H. Camara Jan 2006

Dynamic Sulfur Tolerant Process And System With Inline Acid Gas-Selective Removal For Generating Hydrogen For Fuel Cells, Surjit Randhava, W. S. Winston Ho, Richard L. Kao, Elias H. Camara

Chemical and Materials Engineering Faculty Patents

This invention relates to a sulfur tolerant, dynamic, compact, lightweight fuel process and system that is capable of converting sulfur bearing carbonaceous fuels to hydrogen rich gases suitable for fuel cells or chemical processing applications. The process and system is based on the AHR and WGS reactions, followed by cleanup of byproduct sulfur-containing gases and carbon oxides that would otherwise poison the fuel cell electrocatalyst. Advantageously, this is accomplished via an ASMS and a methanator or an AWMR. The process and system preferably uses a special sulfur tolerant catalysts and hardware designs that enable the conversion in an energy efficient …


Transgenic Non-Human Mammals Producing Fibrinogen In Their Milk, William H. Velander Jan 2006

Transgenic Non-Human Mammals Producing Fibrinogen In Their Milk, William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

A transgenic, non-human mammalian animal is capable of expressing a heterologous gene for human or other recombinant physiologically functional fibrinogen holoprotein or individual subunit chain polypeptides thereof or a modified or fusion fibrinogen in mammary glands of the animals and secreting the expressed product into a body fluid. Methodology employing such a mammal yields recombinant physiologically functional fibrinogens, subunit chain polypeptides thereof, and modified or fusion fibrinogens.


High-Pressure Torsion-Induced Grain Growth In Electrodeposited Nanocrystalline Ni, X. Z. Liao, A. R. Kilmametov, R. Z. Valiev, Hongsheng Gao, Xiaodong Li, A. K. Mukherjee, J. F. Blingert, Y. T. Zhu Jan 2006

High-Pressure Torsion-Induced Grain Growth In Electrodeposited Nanocrystalline Ni, X. Z. Liao, A. R. Kilmametov, R. Z. Valiev, Hongsheng Gao, Xiaodong Li, A. K. Mukherjee, J. F. Blingert, Y. T. Zhu

Faculty Publications

Deformation-induced grain growth has been reported in nanocrystalline (nc) materials under indentation and severe cyclic loading, but not under any other deformation mode. This raises an issue on critical conditions for grain growth in nc materials. This study investigates deformation-induced grain growth in electrodeposited nc Ni during high-pressure torsion (HPT). Our results indicate that high stress and severe plastic deformation are required for inducing grain growth, and the upper limit of grain size is determined by the deformation mode and parameters. Also, texture evolution suggests that grain-boundary-mediated mechanisms played a significant role in accommodating HPT strain.


The Microstructure And Grain Size Of Jet Electroplated Copper Films In Damascene Trench Features, Andrew Tzanavaras, Gregory Young, Stacy H. Gleixner Jan 2006

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

Faculty Publications

The brightening additive level and dc current density of electroplating baths are two parameters that affect the gap-filling capability and the degree of impurity incorporation in electroplated copper films. Additive incorporation can inhibit grain growth during the room temperature recrystallization process and therefore affect the final grain size. This investigation explores the grain size and microstructure of dc jet-electroplated copper films in 0.35 and 0.50μm Damascene trenches as a function of current density and brightening additive level after first receiving a high-temperature anneal. Unlike a previous study that explored these variables in blanket Cu films [ J. Electrochem. Soc. , …


Kinetic Characterization For Pretreatment Of Timber Varieties And Switchgrass Using Diluted Acid Hydrolysis, Shu Chiang Yat Jan 2006

Kinetic Characterization For Pretreatment Of Timber Varieties And Switchgrass Using Diluted Acid Hydrolysis, Shu Chiang Yat

Dissertations, Master's Theses and Master's Reports - Open

In recent years, growing attention has been devoted to the use of lignocellulosic biomass as a feedstock to produce renewable carbohydrates as a source of energy products, including liquid alternatives to fossil fuels. The benefits of developing woody biomass to ethanol technology are to increase the long-term national energy security, reduce fossil energy consumption, lower greenhouse gas emissions, use renewable rather than depletable resources, and create local jobs. Currently, research is driven by the need to reduce the cost of biomass-ethanol production. One of the preferred methods is to thermochemically pretreat the biomass material and subsequently, enzymatically hydrolyze the pretreated …


Ultrafiltration Membrane Process For Pyrogen Removal In The Preparation Of Water For Injection (Wfi), Thet N. Soe Jan 2006

Ultrafiltration Membrane Process For Pyrogen Removal In The Preparation Of Water For Injection (Wfi), Thet N. Soe

Inquiry: The University of Arkansas Undergraduate Research Journal

An artificial kidney process based on ultrafiltration (called hemodiafiltration) more effectively removes blood toxins, particularly those of higher molecular weight, than conventional dialysis. In hemodiafiltration, replacement liquid must be added directly to the patient's blood to replace liquid filtered out of the blood in the ultrafiltration cartridge. This replacement liquid is made up of' "water for injection" (WFI) and other components such as salts and glucose. WFI is produced either by distillation or reverse osmosis and has a cost of $1.00 per liter. A patient with kidney problems would require three hemodiafiltration treatments per week, each requiring 70-80 liters of …


Nanoparticles For Enhanced Delivery Of Chemotherapeutics, Emily J. Bahram-Ahi Jan 2006

Nanoparticles For Enhanced Delivery Of Chemotherapeutics, Emily J. Bahram-Ahi

Opportunities for Undergraduate Research Experience Program (OURE)

Delivery of the anticancer drug paclitaxel (commercially known as Taxol®) is difficult due to its limited solubility in aqueous media. This study proposes a novel bubble bursting technique to generate nanoparticles of the chemotherapeutic in an effort to decrease potential side effects and improve the bioavailability of hydrophobic drugs. The bubble bursting apparatus will be used to produce nanoparticles of a biodegradable polymer, poly(lactide-co-glycolide) (PLGA), as carriers for paclitaxel. The dissolved paclitaxel in this biodegradable polymer matrix will be released at a controlled rate for a more efficient delivery of the drug throughout the body.


Synthesis And Characterization Of Poly(Urethane-Imide)/Poss Nanocomposite, Supanan Patthamasang Jan 2006

Synthesis And Characterization Of Poly(Urethane-Imide)/Poss Nanocomposite, Supanan Patthamasang

Chulalongkorn University Theses and Dissertations (Chula ETD)

A novel type of poly(urethane-imide) (PUI) was prepared by blending the isocyanate terminated polyurethane containing dihydroxy-POSS prepolymer (PU/POSS) and anhydride-terminated polyimide (PI) with various chain lengths of PU/POSS prepolymer and various molecular weights of PI. The effect of chain length of PU prepolymer and molecular weight of PI on the properties of PUI/POSS films was examined. From the results, we found the best condition for synthesis of the PUI/POSS hybrid films is to use the PI prepared via 1 step method with MW of 80,000 and that can prepared the transparent films, follwed by casting films and heat treatment at …


Intracellular Signaling Networks In The Immune Response: Pathways Activated By Interleukin-2 And-4 Receptors And Their Roles In T Cell Proliferation, Kristen K. Comfort Jan 2006

Intracellular Signaling Networks In The Immune Response: Pathways Activated By Interleukin-2 And-4 Receptors And Their Roles In T Cell Proliferation, Kristen K. Comfort

Chemical and Materials Engineering Faculty Publications

Cells sense and respond to chemical and physical stimuli through signal transduction pathways, which mediate cell proliferation, differentiation, migration, and survival. The cytokines interleukin-2 (IL-2) and interleukin-4 (IL-4) are key regulators of the adaptive immune system, particularly influencing the clonal expansion and differentiation of T cells. At least in culture, both synergistic and antagonistic effects of IL-2 and -4 co-stimulation have been reported; the antagonism, when observed, is thought to arise from the utilization of a common subunit shared by IL-2 and IL-4 receptors. We have sought to characterize IL-2 and IL-4 signaling at the level of intracellular pathways activated …


Control Of Plasma Flux Composition Incident On Tin Films During Reactive Magnetron Sputtering And The Effect On Film Microstructure, Christopher Muratore, Scott G. Walton, Darrin Leonhardt, Richard F. Fernsler Jan 2006

Control Of Plasma Flux Composition Incident On Tin Films During Reactive Magnetron Sputtering And The Effect On Film Microstructure, Christopher Muratore, Scott G. Walton, Darrin Leonhardt, Richard F. Fernsler

Chemical and Materials Engineering Faculty Publications

A hybrid plasma enhanced physical vapor deposition (PEPVD) system consisting of an unbalanced dc magnetron and a pulsed electron beam-produced plasma was used to deposit reactively sputtered titanium nitride thin films. The system allowed for control of the magnitudes of the ion and neutral flux, in addition to the type of nitrogen ions (atomic or molecular) that comprised the flux. For all deposition experiments, the magnitude of the ion flux incident on the substrate was held constant, but the composition of the total flux was varied. X-ray diffraction and atomic force microscopy showed that crystallographic texture and surface morphology of …


Development Of An Electroless Method To Deposit Corrosion-Resistant Silicate Layers On Metallic Substrates, Swaminatha P. Kumaraguru, Basker Veeraraghavan, Branko N. Popov Jan 2006

Development Of An Electroless Method To Deposit Corrosion-Resistant Silicate Layers On Metallic Substrates, Swaminatha P. Kumaraguru, Basker Veeraraghavan, Branko N. Popov

Faculty Publications

A novel electroless method for depositing corrosion-resistant silicate layers on metallic substrates from aqueous solutions has been developed. The silicate layer was deposited from an aqueous solution of sodium silicate (3.22 weight ratio sodium silicate, 37.5% solution in water from PQ Corporation) and sodium borohydride. The technique is demonstrated by forming a passive film on galvanized steel. Deposition parameters such as concentration of the bath, temperature, and pH have been optimized based on the corrosion characteristics of the final coating. Studies on the coating reveal the formation of a very thin (5 nm) zinc disilicate layer followed by a much …


Enhanced Degradation Of Phenanthrene And Benzo(A)Pyrene In A Field-Contaminated Sediment Inhabited By Ilyodrilus Templetoni: A Microcosm Study, Marilou Montevirgen Nabatilan Jan 2006

Enhanced Degradation Of Phenanthrene And Benzo(A)Pyrene In A Field-Contaminated Sediment Inhabited By Ilyodrilus Templetoni: A Microcosm Study, Marilou Montevirgen Nabatilan

LSU Master's Theses

The influence of the oligochaete Ilyodrilus templetoni on the degradation of phenanthrene and benzo(a)pyrene present in a field-contaminated sediment was studied in microcosm experiments. Results indicate an enhanced degradation of phenanthrene and benzo(a)pyrene in microcosms inhabited by I. templetoni. Total phenanthrene reduction was observed at an average of 9.78 % in worm microcosms, while no reduction was observed in the control microcosms. Benzo(a)pyrene reduction, on the other hand, was determined at 78.60 % and 30.04 % in worm and control microcosms, respectively. The lowest concentrations of these PAHs at the end of 97-day study were observed well below the surface …


Feasibility Of Supercritical Carbon Dioxide As A Drilling Fluid For Deep Underbalanced Drilling Operations, Anamika Gupta Jan 2006

Feasibility Of Supercritical Carbon Dioxide As A Drilling Fluid For Deep Underbalanced Drilling Operations, Anamika Gupta

LSU Master's Theses

Feasibility of drilling with supercritical carbon dioxide to serve the needs of deep underbalanced drilling operations has been analyzed. A case study involving underbalanced drilling to access a depleted gas reservoir is used to illustrate the need for such a research. For this well, nitrogen was initially considered as the drilling fluid. Dry nitrogen, due to its low density, was unable to generate sufficient torque in the downhole motor. The mixture of nitrogen and water, stabilized as foam generated sufficient torque but made it difficult to maintain underbalanced conditions. This diminished the intended benefit of using nitrogen as the drilling …


Hydrate Dissociation During Drilling Through In-Situ Hydrate Formations, Erdem Catak Jan 2006

Hydrate Dissociation During Drilling Through In-Situ Hydrate Formations, Erdem Catak

LSU Master's Theses

Natural gas hydrates are thought to be the future hydrocarbon source of the energy hungry world. Tremendous amount of research has been done to investigate the feasibility of gas production from the hydrate formations. In this direction, three basic production methods, thermal stimulation, depressurization and thermodynamic inhibitor injection have been proposed to produce hydrocarbons off the hydrates. On the other hand, they present high potential risk of drilling hazards, such as severe gasification of drilling fluid, casing collapse due to increase in pressure after dissociation of hydrate zone, and instability of ocean floor, which may cause a platform failure. Scientists …


Polycyclic Aromatic Compounds In Wood Soot Extracts From Henan, China, Robyn Joy Cabrido Alcanzare Jan 2006

Polycyclic Aromatic Compounds In Wood Soot Extracts From Henan, China, Robyn Joy Cabrido Alcanzare

LSU Master's Theses

Polycyclic aromatic compounds (PAC) are organic compounds composed of two or more fused benzene rings. These compounds are ubiquitous in the environment and some are found to be mutagenic and carcinogenic. High rates of esophageal cancer in the Henan Province of China had led to the suspicion that PAC from domestic coal and wood combustion are the main cause. Extraction of PAC from wood soot was done with a Soxhlet apparatus using dichloromethane as the solvent and concentration of the solution using a Kuderna Danish apparatus. Analysis of the different PAC was performed by high performance liquid chromatography (HPLC) with …


The Bioturbation Transport Of Chemicals In Surface Soils, Maria D. Rodriguez Jan 2006

The Bioturbation Transport Of Chemicals In Surface Soils, Maria D. Rodriguez

LSU Master's Theses

Large quantities of chemicals, such as pesticides, fertilizers, and industrial wastes, have been found throughout the environment raising concerns due to their ecological impacts and implications to human health. Soil is the most important repository of many organic chemicals in the environment. The objective of the present study was to determine the importance of the soil solid phase in the transport of chemicals in soils, and yield quantitative information to better describe bioturbation and its role in the movement of soil particles. Vertical movement of chemicals in the soil solid phase occurs by mixing mechanisms, such as bioturbation, cryoturbation, and …


Accelerating Whole-Cell Biocatalysis By Enhancing Outer Membrane Permeability, Ye Ni Jan 2006

Accelerating Whole-Cell Biocatalysis By Enhancing Outer Membrane Permeability, Ye Ni

Theses and Dissertations

Whole-cell biocatalysts are preferred in many biocatalysis applications. However, cell envelope often represents a formidable permeability barrier. As a result, reactions catalyzed by whole-cells are reportedly orders of magnitude slower than those of by their free enzyme counterparts. The present research addresses this critical issue by using membrane engineering approaches. Two E. coli strains with genetically altered outer membrane structures were used in the study, a lipopolysaccarides (LPS) mutant SM101 and a Braun's lipoprotein mutant E609L. The effects of outer membrane mutation on the permeability of substrates differing substantially in size and hydrophobicity were investigated by combining the mutant cells …


Experimental And Computational Analysis Of Random Cylinder Packings With Applications, Wenli Zhang Jan 2006

Experimental And Computational Analysis Of Random Cylinder Packings With Applications, Wenli Zhang

LSU Doctoral Dissertations

Random cylinder packings are prevalent in chemical engineering applications and they can serve as prototype models of fibrous materials and/or other particulate materials. In this research, comprehensive studies on cylinder packings were carried out by computer simulations and by experiments. The computational studies made use of a collective rearrangement algorithm (based on a Monte Carlo technique) to generate different packing structures. 3D random packing limits were explored, and the packing structures were quantified by their positional ordering, orientational ordering, and the particle-particle contacts. Furthermore, the void space in the packings was expressed as a pore network, which retains topological and …


Electrodeposited Metal Matrix Nanocomposites As Thin Films And High Aspect Ratio Microstructures For Mems, Alonso Lozano Morales Jan 2006

Electrodeposited Metal Matrix Nanocomposites As Thin Films And High Aspect Ratio Microstructures For Mems, Alonso Lozano Morales

LSU Doctoral Dissertations

The electrodeposition of metal-matrix nanocomposites as thin film and high aspect ratio microstructures (HARM’s) for MicroElectroMechanical Systems (MEMS) components is examined. The effect of -Al2O3 nanopowder on copper reduction from acidic and basic electrolytes is examined with rotating disk electrodes (RDE’s). At pH 0.2, regions of copper inhibition and enhancement are identified in the kinetic regime. Low particle loading (12.5 g/L) results in an inhibited copper rate, while, high particle concentration (60 g/L) does both, inhibits the rate at low overpotentials and accelerates it at higher overpotentials, depending on the electrode rotation rate. At pH 8 the presence of particles …


Demonstration And Performance Characterization Of The Gas Assisted Gravity Drainage (Gagd) Process Using A Visual Method, Thaer N.N. Mahmoud Jan 2006

Demonstration And Performance Characterization Of The Gas Assisted Gravity Drainage (Gagd) Process Using A Visual Method, Thaer N.N. Mahmoud

LSU Master's Theses

The Gas Assisted Gravity Drainage (GAGD) process, currently being developed at LSU, is designed to take advantage of gravity to allow vertical segregation between the injected gas and reservoir crud oil due to their density differences. GAGD is recommended for use with CO2 gas. CO2 dissolves in oil and causes both swelling and viscosity reduction of oil. The GAGD process uses the existing vertical wells for CO2 gas injection, and a horizontal well near the bottom of the payzone for oil production. GAGD, as an EOR process, is not restricted to tertiary oil recovery only. In this research study, a …


A Distribution Kinetics Approach For Polymer Crystallization And Phase Separation, Jiao Yang Jan 2006

A Distribution Kinetics Approach For Polymer Crystallization And Phase Separation, Jiao Yang

LSU Doctoral Dissertations

The mechanism of polymer crystallization is extensively studied and still far away from consensus. This research adopted cluster size distribution kinetics approach to explore the kinetics of polymer crystallization and phase separation within spinodal region. The kinetics of polymer crystallization is studied by integrating nucleation, crystal growth and ripening. Population balance equations based on crystal size distribution and concentration of amorphous polymer segments are solved numerically and the related differential moment equations are also solved. The model accounts for nucleation and crystal growth. Different mass dependences of growth and dissociation rate coefficients are proposed to investigate the fundamental features of …


Electrodeposition Of Cocu Nanostructures, Yutong Li Jan 2006

Electrodeposition Of Cocu Nanostructures, Yutong Li

LSU Doctoral Dissertations

Electrodeposition is a key component in the microelectronic industry because it has the following advantages: low cost, easy operation and the capability to deposit into irregular geometries such as recessed and curved areas. In this dissertation, CoCu alloys were investigated to fabricate multilayers, microdevices and microposts. All of these multilayer structures were composed of nanometric copper and cobalt-rich layers in order to obtain magnetoresistance, a phenomenon where the resistance of multilayer structures decreases with increases of external magnetic field. An investigation was carried out in order to evaluate appropriate plating conditions during multilayered thin film deposition, with the aim to …


Overview Of Cogeneration At Lsu, Robert,Jr. Buckley Jan 2006

Overview Of Cogeneration At Lsu, Robert,Jr. Buckley

LSU Master's Theses

Cogeneration (or Combined Heat and Power) continues to gain importance in power production because of its high efficiency, environmental friendliness, and flexibility. Louisiana State University (LSU) recently began operation of a new 20 MW cogeneration system. This new facility can serve as a useful learning tool for chemical and mechanical engineering students throughout their education at LSU. The goal of this project is to develop educational modules utilizing the cogeneration system which have industrial significance. Educational modules will include: a comparison of ideal gas versus real gas thermodynamics for a cogeneration optimization problem, a cogeneration data reconciliation problem, and a …


Distribution Dynamics Of Complex Systems, Young-Pyo Jeon Jan 2006

Distribution Dynamics Of Complex Systems, Young-Pyo Jeon

LSU Doctoral Dissertations

A complex system is defined as a system with many interdependent parts having emergent self-organization; analyzing and designing such complex systems is a new challenge. A common observable structure of many complex systems is the network, which is connections among nodes, and thus inherently difficult to describe. The goal of this research is to introduce an effective methodology to describe complex systems, and thus we will construct a population balance (distribution kinetics) model based on the association-dissociation process to describe the evolution of complex systems. Networks are commonly observed structures in complex systems with interdependent parts that self-organize. How networks …


Enzyme Engineering Of Aminotransferases For Improved Activity And Thermostability, Abraham Rogelio Mártin García Jan 2006

Enzyme Engineering Of Aminotransferases For Improved Activity And Thermostability, Abraham Rogelio Mártin García

Dissertations, Master's Theses and Master's Reports - Open

The production by biosynthesis of optically active amino acids and amines satisfies the pharmaceutical industry in its demand for chiral building blocks for the synthesis of various pharmaceuticals. Among several enzymatic methods that allow the synthesis of optically active aminoacids and amines, the use of minotransferase is a promising one due to its broad substrate specificity and no requirement for external cofactor regeneration. The synthesis of chiral compounds by aminotransferases can be done either by asymmetric synthesis starting from keto acids or ketones, and by kinetic resolution starting from racemic aminoacids or amines.

The asymmetric synthesis of substituted (S)-aminotetralin, an …


Surface Modification Of Su-8 By Photografting Of Functional Polymers For Lab-On-A-Chip Applications, Zhan Gao, David Henthorn, Chang-Soo Kim Jan 2006

Surface Modification Of Su-8 By Photografting Of Functional Polymers For Lab-On-A-Chip Applications, Zhan Gao, David Henthorn, Chang-Soo Kim

Chemical and Biochemical Engineering Faculty Research & Creative Works

Due to the high flexibility and versatility in the process development of microfluidic devices, an epoxybased, high-aspect ratio photoresist SU-8 is now attracting attention as the main structuring material of the fluidic channels. Manipulation of the surface properties of SU-8 channel wall is critical to attach functional films such as enzyme-immobilized layers or biocompatible layers. We describe a new in situ patterning method to form a hydrogel film on SU-8 by a photografted polymerization procedure. The hydrophobic surface of SU-8 is modified using a surface bound initiator HCPK (1-hydroxycyclohexyl phenyl ketone). A p-HEMA (poly-2-hydroxyethylmethacrylate) hydrogel film is grafted by photopolymerization …


Purification And Scale-Up Of A Recombinant Heavy Chain Fragment C Of Botulinum Neurotoxin Serotype E In Pichia Pastoris Gs115, Michael P. Dux, Rick Barent, Jayanta Sinha, Mark Gouthro, Todd Swanson, Ardis Barthuli, Mehmet Inan, John T. Ross, Leonard A. Smith, Theresa J. Smith, Robert Webb, Bonnie Loveless, Ian Henderson, Michael M. Meagher Jan 2006

Purification And Scale-Up Of A Recombinant Heavy Chain Fragment C Of Botulinum Neurotoxin Serotype E In Pichia Pastoris Gs115, Michael P. Dux, Rick Barent, Jayanta Sinha, Mark Gouthro, Todd Swanson, Ardis Barthuli, Mehmet Inan, John T. Ross, Leonard A. Smith, Theresa J. Smith, Robert Webb, Bonnie Loveless, Ian Henderson, Michael M. Meagher

Michael Meagher Publications

A recombinant C-terminus heavy chain fragment from botulinum neurotoxin serotype E (BoNT/E) is proposed as a vaccine against the serotype E neurotoxin. This fragment, rBoNTE(Hc), was produced intracellular in Pichia pastoris GS115 by a three-step fermentation process, i.e., glycerol batch phase and a glycerol fed-batch phase to achieve high cell densities, followed by a methanol fed-batch induction phase. The rBoNTE(Hc) protein was purified from the soluble fraction of cell lysates using three ion-exchange chromatography steps (SP Sepharose Fast Flow, Q Sepharose Fast Flow, Sp Sepharose High Performance) and polished with a hydrophobic charge induction chromatography step …


Modeling Volume Changes In Porous Electrodes, Parthasarathy M. Gomadam, John W. Weidner Jan 2006

Modeling Volume Changes In Porous Electrodes, Parthasarathy M. Gomadam, John W. Weidner

Faculty Publications

A three-dimensional mathematical model is presented to describe volume changes in porous electrodes occurring during operation. Material conservation equations are used to derive governing relationships between electrode dimensions and porosity for deposition/precipitation, intercalation, and ionomer-based electrodes. By introducing a parameter, called the swelling coefficient, the relative magnitudes of the change in electrode dimensions and the change in porosity are determined. The swelling coefficient is design-dependent and measured experimentally for a given cell design. The model is general and forms a critical addition required to extend the existing porous electrode models to include volume change effects. For the special case of …


Combinatorial Study Of Ni-Ti-Pt Ternary Metal Gate Electrodes On Hfo2 For The Advanced Gate Stack, K.-S. Chang, M. L. Green, J. Suehle, E. M. Vogel, H. Xiong, Jason R. Hattrick-Simpers, I. Takeuchi, O. Famodu, K. Ohmori, P. Ahmet, T. Chikyow, P. Majhi, B.-H. Lee, M. Gardner Jan 2006

Combinatorial Study Of Ni-Ti-Pt Ternary Metal Gate Electrodes On Hfo2 For The Advanced Gate Stack, K.-S. Chang, M. L. Green, J. Suehle, E. M. Vogel, H. Xiong, Jason R. Hattrick-Simpers, I. Takeuchi, O. Famodu, K. Ohmori, P. Ahmet, T. Chikyow, P. Majhi, B.-H. Lee, M. Gardner

Faculty Publications

The authors have fabricated combinatorial Ni–Ti–Pt ternary metal gate thin film libraries on HfO2 using magnetron co-sputtering to investigate flatband voltage shift (ΔVfb) , work function (Φm) , and leakage current density (JL) variations. A more negative ΔVfb is observed close to the Ti-rich corner than at the Ni- and Pt-rich corners, implying smaller Φm near the Ti-rich corners and higher Φm near the Ni- and Pt-rich corners. In addition, measured JL values can be explained consistently with the observed Φm variations. Combinatorial methodologies prove to be useful …


Development And Modeling Of Thermally Conductive Resins For Fuel Cell Bipolar Plate Applications, Michael G. Miller Jan 2006

Development And Modeling Of Thermally Conductive Resins For Fuel Cell Bipolar Plate Applications, Michael G. Miller

Dissertations, Master's Theses and Master's Reports - Open

Thermally conductive resins are a class of material that show promise in many different applications. One growing field for their use is in the area of bipolar plate technology for fuel cell applications. In this work, a LCP was mixed with different types of carbon fillers to determine the effects of the individual carbon fillers on the thermal conductivity of the composite resin. In addition, mathematical modeling was performed on the thermal conductivity data with the goal of developing predictive models for the thermal conductivity of highly filled composite resins.