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Full-Text Articles in Chemical Engineering

Electrospinning Applications Air Filtration And Superhydrophobic Materials, Negar Ghochaghi, Adetoun Taiwo Jan 2014

Electrospinning Applications Air Filtration And Superhydrophobic Materials, Negar Ghochaghi, Adetoun Taiwo

Graduate Research Posters

Electrospinning is a widely applicable technique that generates non-woven fibers in the micro and nano range. In this project two of its applications are highlighted namely filtration media and enhancement of wettability. The first project demonstrates that electrospinning can be used to produce new fiber filtration media with controlled microstructure. The bimodal and unimodal orthogonal and random filters were made and characterized against their filtration efficiency and pressure drop. Figure of Merit (FOM) was also calculated and discussed. It is shown that the FOM increases when the electrospun fibers are arranged into alternating layers of aligned course and fine fibers. …


Reuse Of The Product Obtained On Grinding Kiln Rollers In The Manufacture Of Ceramic Wall Tiles, Mai H. Roushdy, Shereen K. Amin, Marwa Mohamed, Magdi F. Abadir Jan 2014

Reuse Of The Product Obtained On Grinding Kiln Rollers In The Manufacture Of Ceramic Wall Tiles, Mai H. Roushdy, Shereen K. Amin, Marwa Mohamed, Magdi F. Abadir

Chemical Engineering

The production of ceramic tiles and to a lesser extent flat dinner ware and pottery is increasingly being done by firing in roller kilns. These kilns offer several advantages over conventional tunnel kilns: lower fuel consumption, computer controlled firing curves, low maintenance due to lack of kiln cars, rapid firing cycles of less than one hour and the possibility of shutting down the kiln on short notice.1 One recurrent problem in the operation of such kilns is the periodic need to grind the kiln rollers. These are usually fabricated from high alumina clays and are continuously contaminated by depositions of …


Physiological Fluid Specific Agglomeration Patterns Diminish Gold Nanorod Photothermal Characteristics, Kristen K. Comfort, Jared W. Speltz, Bradley M. Stacy, Larry R. Dosser, Saber M. Hussain Nov 2013

Physiological Fluid Specific Agglomeration Patterns Diminish Gold Nanorod Photothermal Characteristics, Kristen K. Comfort, Jared W. Speltz, Bradley M. Stacy, Larry R. Dosser, Saber M. Hussain

Chemical and Materials Engineering Faculty Publications

Investigations into the use of gold nanorods (Au-NRs) for biological applications are growing exponentially due to their distinctive physicochemical properties, which make them advantageous over other nanomaterials. Au-NRs are particularly renowned for their plasmonic characteristics, which generate a robust photothermal response when stimulated with light at a wavelength matching their surface plasmon resonance. Numerous reports have explored this nanophotonic phenomenon for temperature driven therapies; however, to date there is a significant knowledge gap pertaining to the kinetic heating profile of Au-NRs within a controlled physiological setting. In the present study, the impact of environmental composition on Au-NR behavior and degree …


The Use Of Near Infrared And Microwave Sensing For On-Line Real Time Monitoring Of Moisture Content And Composition Of Powder Blend, Ryan V. Mcdonnell, Anshu Gupta, John Austin, Michael T. Harris, Gintaras V. Reklaitis Oct 2013

The Use Of Near Infrared And Microwave Sensing For On-Line Real Time Monitoring Of Moisture Content And Composition Of Powder Blend, Ryan V. Mcdonnell, Anshu Gupta, John Austin, Michael T. Harris, Gintaras V. Reklaitis

The Summer Undergraduate Research Fellowship (SURF) Symposium

Online process analytics has been a topic of interest by pharmaceutical companies as a method of determining how operating parameters affect the final quality of their products. One form of online process analytics that has been found to be effective is microwave sensing. While it has been found that microwave resonance sensing can be used to measure parameters such as moisture content and density, it has yet to be discovered if such sensors have the ability to measure changes in content uniformity of raw materials pharmaceutical companies use. Data was collected using a spin riffler fitted with a microwave sensor …


Tobacco Mosaic Virus Implemented As An Interfacial Layer In Organic Photovoltaic Cells, Monica D. Del Real, Bryan Boudouris Oct 2013

Tobacco Mosaic Virus Implemented As An Interfacial Layer In Organic Photovoltaic Cells, Monica D. Del Real, Bryan Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Organic photovoltaics (OPVs) are flexible, light weight, and economical to produce due to low processing temperatures, solution processing, and print fabrication. This makes them optimal for a wide range of applications. However, the efficiencies of OPVs are currently not high enough for them to be viable in the market or to be able to compete with inorganic photovoltaics. Therefore the integration of new materials and methods into OPVs in order to increase their efficiency is a vital field. One way to increase the efficiency of OPVs is to increase the surface area in-between layers to allow for enhanced electron transport. …


The Biological Impact Of Concurrent Exposure To Metallic Nanoparticles And A Static Magnetic Field, Kristen K. Comfort, Elizabeth I. Maurer, Saber M. Hussain Oct 2013

The Biological Impact Of Concurrent Exposure To Metallic Nanoparticles And A Static Magnetic Field, Kristen K. Comfort, Elizabeth I. Maurer, Saber M. Hussain

Chemical and Materials Engineering Faculty Publications

The rapid advancement of technology has led to an exponential increase of both nanomaterial and magnetic field utilization in applications spanning a variety of sectors. While extensive work has focused on the impact of these two variables on biological systems independently, the existence of any synergistic effects following concurrent exposure has yet to be investigated. This study sought to ascertain the induced alterations to the stress and proliferation responses of the human adult low calcium, high temperature keratinocyte (HaCaT) cell line by the application of a static magnetic field (approximately 0.5 or 30 mT) in conjunction with either gold or …


Multiscale Modeling Of Enzyme-Catalyzed Methanol Production By Particulate Methane Monooxygenase, Katherine K. Bearden Apr 2013

Multiscale Modeling Of Enzyme-Catalyzed Methanol Production By Particulate Methane Monooxygenase, Katherine K. Bearden

Doctoral Dissertations

In this work, the conversion of methane to methanol by the particulate Methane Monooxygenase (pMMO) enzyme is investigated using a multi-scale modeling approach. This enzyme participates in carbon cycling and aids in the removal of harmful atmospheric methane, converting it to methanol. The interaction between pMMO and a neighboring enzyme that is present in the same organism is studied, and the unknown pMMO active site is elucidated and tested for methane oxidation towards the production of methanol.

Fundamental knowledge of pMMO's mechanism is not fully understood. Understanding how this enzyme works in nature will provide information towards designing efficient synthetic …


Comparison Of Biomass To Bio-Oils Reactor Systems: Direct Conversion Vs. Companion Coal Gasification, Alexandra Eicher Apr 2013

Comparison Of Biomass To Bio-Oils Reactor Systems: Direct Conversion Vs. Companion Coal Gasification, Alexandra Eicher

Honors Theses and Capstones

It is well known that the United States’ dependence on crude-oil negatively affects its economy, safety, and environment. To alleviate these negative consequences, a more economical and environmentally-friendly source of fuel, such as biomass, should be explored. The conversion of biomass to bio-oils involves the pyrolysis of biomass at about 500°C, thus requiring a great deal of heat. This heat source could be the excess waste heat from a coal gasifier.

As such, this report specifies the design of an industrial plant that produces bio-oils from biomass by using the waste heat from a coal gasifier. It is designed to …


Married Coal Gasification And Biomass Pyrolysis, Michael Balch Apr 2013

Married Coal Gasification And Biomass Pyrolysis, Michael Balch

Honors Theses and Capstones

This project is a proposal to marry a coal gasification process to a biomass pyrolysis. Coal is pyrolized to produce syngas and a large amount of heat. The syngas is treated and fed to a Fischer-Tropsch process. The excess heat produces steam that is used to pyrolize biomass. The biomass produces char, gas, and vapor. The char and gas are recovered, and the vapor is condensed to produce bio-oil.

The proposed plant has a capacity of 1100 tons of biomass (550 dry tons) per day. I assumed an operating factor of 0.9 The plant could be operational within five years, …


Study Of An Alternative Process For Oxidizing Vapor Grown Carbon Nanofibers Using Electron Beam Accelerators, Maria Cecília Evora, Donald A. Klosterman, Khalid Lafdi, Lingchuan Li, L.G.A. Silva Mar 2013

Study Of An Alternative Process For Oxidizing Vapor Grown Carbon Nanofibers Using Electron Beam Accelerators, Maria Cecília Evora, Donald A. Klosterman, Khalid Lafdi, Lingchuan Li, L.G.A. Silva

Chemical and Materials Engineering Faculty Publications

The use of a high-energy electron beam was explored in this study as an alternative technique for oxidizing vapor grown carbon nanofiber surfaces. The radiation exposures were carried out at three different electron beam facilities with beam energies of 1.5, 3.0 and 4.5 MeV and radiation doses ranging from 1000 to 3500 kGy. XPS analysis showed that oxygen was readily incorporated on the surface: the ratio O1s/C1s increased approximately by a factor of 4 when the carbon nanofibers were irradiated at 3500 kGy. The oxidized nanofibers exhibited better dispersion in a water/methanol solution (50% v/v) than as-received nanofibers. Raman spectroscopy …


Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. J. Metting, Johnathan K. Bunn, Ellen A. Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason R. Hattrick-Simpers Mar 2013

Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. J. Metting, Johnathan K. Bunn, Ellen A. Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason R. Hattrick-Simpers

Faculty Publications

A gradient annealing cell has been developed for the high-throughput study of thermalannealing effects on thin-film libraries in different environments. The inexpensive gradientannealing unit permits temperature gradients as large as 28 °C/mm and can accommodate samples ranging in length from 13 mm to 51 mm. The system was validated by investigating the effects of annealing temperature on the crystallinity, resistivity, and transparency of tin-doped indium oxide deposited on a glass substrate by magnetron sputtering. The unit developed in this work will permit the rapid optimization of materials properties such as crystallinity, homogeneity, and conductivity across a variety of applications.


Modeling Of Biorefinery Supply Chain Economic Performance With Discrete Event Simulation, Joseph S. Amundson Jan 2013

Modeling Of Biorefinery Supply Chain Economic Performance With Discrete Event Simulation, Joseph S. Amundson

Theses and Dissertations--Manufacturing Systems Engineering

As competition for fossil fuels accelerates, alternative sources of chemicals, fuels, and energy production become more appealing to researchers and the layman. Among the candidates to fill this growing niche is lignocellulosic biomass. Many researchers have examined supply chain design and optimization for biofuel and bioenergy production throughout the years. However, these models often fail to capture the variability and uncertainty inherent to the biomass supply chain. Multiple factors with high degrees of stochasticity can have major impacts on the performance of a biorefinery: weather, biomass quality, feedstock availability, and market demand for products are just a few. To begin …


Infrared Optical Properties Of Amorphous And Nanocrystalline Ta2o5 Thin Films, Trevor J. Bright, J. I. Watjen, Zhuomin Zhang, Christopher Muratore, Andrey A. Voevodin, D. I. Koukis, David B. Tanner, Daniel J. Arenas Jan 2013

Infrared Optical Properties Of Amorphous And Nanocrystalline Ta2o5 Thin Films, Trevor J. Bright, J. I. Watjen, Zhuomin Zhang, Christopher Muratore, Andrey A. Voevodin, D. I. Koukis, David B. Tanner, Daniel J. Arenas

Chemical and Materials Engineering Faculty Publications

The optical constants of tantalum pentoxide (Ta 2O5) are determined in a broad spectral region from the visible to the far infrared. Ta 2O5 films of various thicknesses from approximately 170 to 1600 nm aredeposited using reactive magnetron sputtering on Si substrates. X-ray diffraction shows that the as-deposited films are amorphous, and annealing in air at 800 °C results in the formation of nanocrystallineTa 2O5. Ellipsometry is used to obtain the dispersion in the visible and near-infrared. Two Fourier-transform infrared spectrometers are used to measure the transmittance and reflectance at wavelengths from 1 to 1000 μm. The surface topography and …


Cross-Plane Thermal Properties Of Transition Metal Dichalcogenides, Christopher Muratore, Vikas Varshney, Jaime J. Gengler, Jianjun Hu, John E. Bultman, Timothy M. Smith, Patrick J. Shamberger, Bo Qiu, Xiulin Ruan, Ajit K. Roy, Andrey A. Voevodin Jan 2013

Cross-Plane Thermal Properties Of Transition Metal Dichalcogenides, Christopher Muratore, Vikas Varshney, Jaime J. Gengler, Jianjun Hu, John E. Bultman, Timothy M. Smith, Patrick J. Shamberger, Bo Qiu, Xiulin Ruan, Ajit K. Roy, Andrey A. Voevodin

Chemical and Materials Engineering Faculty Publications

In this work, we explore the thermal properties of hexagonal transition metal dichalcogenide compounds with different average atomic masses but equivalent microstructures. Thermal conductivity values of sputtered thin films were compared to bulk crystals. The comparison revealed a >10 fold reduction in thin film thermal conductivity. Structural analysis of the films revealed a turbostratic structure with domain sizes on the order of 5–10 nm. Estimates of phonon scattering lengths at domain boundaries based on computationally derived group velocities were consistent with the observed film microstructure, and accounted for the reduction in thermal conductivity compared to values for bulk crystals.


Tannic Acid Coated Gold Nanorods Demonstrate A Distinctive Form Of Endosomal Uptake And Unique Distribution Within Cells, Emily A. Untener, Kristen K. Comfort, Elizabeth I. Maurer, Christin M. Grabinski, Donald A. Comfort, Saber M. Hussain Jan 2013

Tannic Acid Coated Gold Nanorods Demonstrate A Distinctive Form Of Endosomal Uptake And Unique Distribution Within Cells, Emily A. Untener, Kristen K. Comfort, Elizabeth I. Maurer, Christin M. Grabinski, Donald A. Comfort, Saber M. Hussain

Chemical and Materials Engineering Faculty Publications

One of the primary challenges associated with nanoparticle-dependent biological applications is that endosomal entrapment in a physiological environment severely limits the desired targeting and functionality of the nanoconstructs. This study sought to overcome that challenge through a systematic approach of gold nanorod (GNR) functionalization: evaluating the influence of both aspect ratio and surface chemistry on targeted cellular internalization rates and preservation of particle integrity. Owing to their unique spectral properties and enhanced surface area, GNRs possess great potential for the advancement of nanobased delivery and imaging applications. However, their ability for efficient intracellular delivery while maintaining their specific physiochemical parameters …


Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers Jan 2013

Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers

Faculty Publications

High throughput (combinatorial) materials science methodology is a relatively new research paradigm that offers the promise of rapid and efficient materials screening, optimization, and discovery. The paradigm started in the pharmaceutical industry but was rapidly adopted to accelerate materials research in a wide variety of areas. High throughput experiments are characterized by synthesis of a “library” sample that contains the materials variation of interest (typically composition), and rapid and localized measurement schemes that result in massive data sets. Because the data are collected at the same time on the same “library” sample, they can be highly uniform with respect to …


Capacity Fade Model For Spinel Limn2O4 Electrode, Yiling Dai, Long Cai, Ralph E. White Jan 2013

Capacity Fade Model For Spinel Limn2O4 Electrode, Yiling Dai, Long Cai, Ralph E. White

Faculty Publications

A mathematical model for the capacity fade of a LiMn2O4 (LMO) electrode is developed in this paper by including the acid attack on the active material and the solid electrolyte interphase (SEI) film formation on the LMO particle surface. The acid generated by the LiPF6 and the solvent decompositions are coupled to the manganese (Mn) dissolution. The decrease of the Li ion diffusion coefficient is involved as another contribution to the capacity fade, which is caused by the passive film formation on the active material surface. The effects of cell practical operation/fabrication conditions and kinetics of …


Characterization Of And Controlling Morphology Of Ultra-Thin Nanocomposites, Guy C. Laine Jan 2013

Characterization Of And Controlling Morphology Of Ultra-Thin Nanocomposites, Guy C. Laine

Theses and Dissertations--Chemical and Materials Engineering

Ultrathin film nanocomposites are becoming increasingly important for specialized performance of commercial coatings. Critical challenges for ultrathin film nanocomposites include their synthesis and characterization as well as their performance properties, including surface roughness, optical properties (haze, refractive index as examples), and mechanical properties. The objective of this work is to control the surface roughness of ultrathin film nanocomposites by changing the average particle size and the particle volume fraction (loading) of monomodal particle size distributions. This work evaluated one-layer and two-layer films for their surface properties. Monodispersed colloidal silica nanoparticles were incorporated into an acrylate-based monomer system as the model …


Energy Analysis Of Bio-Ethanol Dehydration Using Pervaporative Processes, Michel Elia Kahwaji Janho Sep 2012

Energy Analysis Of Bio-Ethanol Dehydration Using Pervaporative Processes, Michel Elia Kahwaji Janho

Undergraduate Research Posters 2012

Environmental effects and health hazards posed by fossil-fuel based technologies complemented by changes in the global economy have increased the demand for “cleaner” and more efficient technologies. Developments in technologies that rely on renewable or synthetic resources have therefore become more relevant in today’s economy and current industrial outlook. This study focuses on a critical assessment of pervaporation as a dehydration technique in the production of ethanol from sugar-cane. Energy demands of various separation schemes using this technique are evaluated.


Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson Aug 2012

Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Small scale, high power density, reliable, and long-life power supplies would be useful or even critical for space missions or the growing number of microdetectors, microsensors, and miniature vehicles. Alpha or beta particle voltaic devices could satisfy these requirements but have been shown to degrade quickly due to radiation damage. Amorphous carbon (a-C) PN junctions or PIN devices could provide radiation hardness and sufficiently high efficiency. As the range of alpha and beta particles in a-C is ~20-120μm, much thicker films than are typical are needed to maximize collection of the particle energy.

In this work, the fabrication of thermomechanically …


Cloning And Characterization Of Sas0754, A Hypothetical Protein From Community Associated Staphylococcus Aureus, Unknown Unknown May 2012

Cloning And Characterization Of Sas0754, A Hypothetical Protein From Community Associated Staphylococcus Aureus, Unknown Unknown

Symposium 2012

Community associated Staphylococcus aureus (strain MSSA476) is a gram positive cocci capable of infecting many different parts of the body and known to cause serious infections that can be fatal, such as bacterial arthritis and acute endocarditis. To find effective ways of fighting against CA-MRSA strains we must learn more about their ability to infect. The focus of this study was cloning and characterization of a protein referred to as SAS0754. The size of SAS0754 is 340 amino acids and the gene sequence is 1023 nucleotides. The hypothetical function of this protein is that it is an extracellular matrix binding …


A Convenient Synthesis Of 2,6-Dichlorohomonicotinic Acid, Chase Buchanan, Richard W. Fitch May 2012

A Convenient Synthesis Of 2,6-Dichlorohomonicotinic Acid, Chase Buchanan, Richard W. Fitch

Symposium 2012

In our synthetic efforts toward the alkaloid phantasmidine, we required a convenient source of the title compound. Herein, we describe a short synthesis of 2,6-dichlorohomonicotinic acid by direct allylation of 2,6-dichloropyridine with LDA/allyl chloride, followed by permanganate oxidation of the side chain [figure1]. Yields for the allylation are high, while permanganate oxidation required more adjustment. Successful conditions require the modest acidification of the mixture with acetic acid and cleanup by acid base workup. No chromatography is needed.


Convenient Parallel Synthesis Of Alkyl- And Aryl-S-Tert-Butyl Thiothers, Rebecca Norcross, Jessica Stanfield, Richard W. Fitch May 2012

Convenient Parallel Synthesis Of Alkyl- And Aryl-S-Tert-Butyl Thiothers, Rebecca Norcross, Jessica Stanfield, Richard W. Fitch

Symposium 2012

While preparing novel cysteine derivatives as oxidation catalysts, we needed S-tert-butylcysteine. We also examined acid-promoted tert-butylation of thiols using tert-butanol as reagent and solvent. While cysteine and aminoethanethiol work well using tBuOH in 4M HCl, other thiols fail in the aqueous environment and aerobic conditions. We examined a variety of aliphatic and aromatic thiols in tBuOH with H2SO4 catalysis and found that argon sparging and the use of 1 eq of acid led to good yields in a parallel format.


Plasmonic Nanogel: Structure, Rheology, And Optical Properties, Georo Zhou May 2012

Plasmonic Nanogel: Structure, Rheology, And Optical Properties, Georo Zhou

Renée Crown University Honors Thesis Projects - All

The invention of plasmonic nanogels (PNG) opens up the field of nanotechnology to a wide variety of applications such as, enhanced light trapping in solar cells, design of smart glasses, chemical detection, and optofluidic devices. In this work, it was determined that, the synthesis of a nanoparticle-micelle network in a fluid state is performed with the ability to suspend metal nanoparticles in a gel-like solution in a stable fashion. Furthermore, the stable suspension of the nanoparticles in the fluidic system allows the user to easily tune the PNG’s optical and rheological properties by controlling the concentration of the nanoparticles and …


Biomedical Properties And Preparation Of Iron Oxide-Dextran Nanostructures By Maple Technique, Carmen Steluta Ciobanu, Simona Liliana Iconaru, Eniko Gyorgy, Mihaela Radu, Marieta Costache, Anca Dinischiotu, Philippe Le Coustumer, Khalid Lafdi, Daniela Predoi Mar 2012

Biomedical Properties And Preparation Of Iron Oxide-Dextran Nanostructures By Maple Technique, Carmen Steluta Ciobanu, Simona Liliana Iconaru, Eniko Gyorgy, Mihaela Radu, Marieta Costache, Anca Dinischiotu, Philippe Le Coustumer, Khalid Lafdi, Daniela Predoi

Chemical and Materials Engineering Faculty Publications

Background: In this work the chemical structure of dextran-iron oxide thin films was reported. The films were obtained by MAPLE technique from composite targets containing 10 wt. % dextran with 1 and 5 wt.% iron oxide nanoparticles (IONPs). The IONPs were synthesized by co-precipitation method. A KrF* excimer laser source (λ = 248 nm, τFWHM≅25 ns, ν = 10 Hz) was used for the growth of the hybrid, iron oxide NPs-dextran thin films.

Results: Dextran coated iron oxide nanoparticles thin films were indexed into the spinel cubic lattice with a lattice parameter of 8.36 Å. The particle sized calculated was …


Carbon Nanotubes Grown On Glass Fiber As A Strain Sensor For Real Time Structural Health Monitoring, Matthew Boehle, Qiong Jiang, Lingchuan Li, Alexandre Lagounov, Khalid Lafdi Feb 2012

Carbon Nanotubes Grown On Glass Fiber As A Strain Sensor For Real Time Structural Health Monitoring, Matthew Boehle, Qiong Jiang, Lingchuan Li, Alexandre Lagounov, Khalid Lafdi

Chemical and Materials Engineering Faculty Publications

In order to more effectively monitor the health of composite structures, a fuzzy fiber sensor has been developed. The fuzzy fiber is a bundle of glass fibers with carbon nanotubes or nanofibers (CNTs or CNFs) grown on the surface. The nanotube coating makes the fiber bundle conductive while the small conductive path increases sensitivity. The fuzzy fiber sensor can replace conventional metal foil strain gauges in composite applications. The electrical response of the sensor is monitored in real time to measure strain, vibration, cracking and delamination. Continuous monitoring provides instant notification of any problems. Implementation of this sensor network in …


Limited Thermal Conductance Of Metal-Carbon Interfaces, Jaime J. Gengler, Sergei V. Shenogin, John E. Bultman, Ajit K. Roy, Andrey A. Voevodin, Christopher Muratore Jan 2012

Limited Thermal Conductance Of Metal-Carbon Interfaces, Jaime J. Gengler, Sergei V. Shenogin, John E. Bultman, Ajit K. Roy, Andrey A. Voevodin, Christopher Muratore

Chemical and Materials Engineering Faculty Publications

The thermal conductance for a series of metal-graphite interfaces has been experimentally measured with time-domain thermoreflectance (TDTR). For metals with Debye temperatures up to ∼400 K, a linear relationship exists with the thermal conductance values. For metals with Debye temperatures in excess of ∼400 K, the measured metal-graphite thermal conductance values remain constant near 60 MW m−2 K−1. Titanium showed slightly higher conductance than aluminum, despite the closeness of atomic mass and Debye temperature for the two metals. Surface analysis was used to identify the presence of titaniumcarbide at the interface in contrast to the aluminum and gold-carbon interfaces (with …


Design Mixers To Minimize Effects Of Erosion And Corrosion Erosion, Julian B. Fasano, Eric E. Janz, Kevin J. Myers Jan 2012

Design Mixers To Minimize Effects Of Erosion And Corrosion Erosion, Julian B. Fasano, Eric E. Janz, Kevin J. Myers

Chemical and Materials Engineering Faculty Publications

A thorough review of the major parameters that affect solid-liquid slurry wear on impellers and techniques for minimizing wear is presented. These major parameters include (i) chemical environment, (ii) hardness of solids, (iii) density of solids, (iv) percent solids, (v) shape of solids, (vi) fluid regime (turbulent, transitional, or laminar), (vii) hardness of the mixer's wetted parts, (viii) hydraulic efficiency of the impeller (kinetic energy dissipation rates near the impeller blades), (ix) impact velocity, and (x) impact frequency. Techniques for minimizing the wear on impellers cover the choice of impeller, size and speed of the impeller, alloy selection, and surface …


Quantifying Cell-To-Cell Variations In Lithium Ion Batteries, Shriram Santhanagopalan, Ralph E. White Jan 2012

Quantifying Cell-To-Cell Variations In Lithium Ion Batteries, Shriram Santhanagopalan, Ralph E. White

Faculty Publications

Lithium ion batteries have conventionally been manufactured in small capacities but large volumes for consumer electronics applications. More recently, the industry has seen a surge in the individual cell capacities, as well as the number of cells used to build modules and packs. Reducing cell-to-cell and lot-to-lot variations has been identified as one of the major means to reduce the rejection rate when building the packs as well as to improve pack durability. The tight quality control measures have been passed on from the pack manufactures to the companies building the individual cells and in turn to the components. This …


Development Of Strategies To Minimize The Release Of Trace Elements From Coal Waste Sources, Mohammad Rezaee Jan 2012

Development Of Strategies To Minimize The Release Of Trace Elements From Coal Waste Sources, Mohammad Rezaee

Theses and Dissertations--Mining Engineering

To assess strategies aimed at minimizing the release of trace elements and the impact of disposal of coal waste materials on the environment, two long-term leaching experiments of up to five months duration were performed using waste materials from two plants cleaning high and low sulfur bituminous coal. The tests evaluated the mobility of major trace elements under different disposal scenarios: (i) a static leaching test designed to simulate the quiescent conditions encountered by coal waste material stored under water in a stable impoundment, and (ii) a dynamic test to simulate waste materials exposed to the atmosphere, either in variable …