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Full-Text Articles in Engineering

Improving Quality Of Patient Care Through Automated Nerve Segmentation, Madisen D. Phillips Jun 2017

Improving Quality Of Patient Care Through Automated Nerve Segmentation, Madisen D. Phillips

Maseeh Summer Undergraduate Research Experience

A continuous peripheral nerve block cPNB is most commonly used in patients during the post-operative period, with documented benefits that include a decrease in reported pain, a decrease of opioid related side effects, and an increase in patient satisfaction. Accurately identifying nerve structures for cPNB placement is a critical step for proper insertion. The aim of this research is to use supervised learning techniques (least squares regression and Receiver Operating Characteristic (ROC) curve analysis) to build a model that can segment and annotate a bundle of nerves known as the brachial plexus (BP) while minimizing segmentation error. Dependent on large …


Heteromer Nanostars By Spontaneous Self-Assembly, Caitlin Brocker, Hannah Kim, Daniel Smith, Sutapa Barua Jun 2017

Heteromer Nanostars By Spontaneous Self-Assembly, Caitlin Brocker, Hannah Kim, Daniel Smith, Sutapa Barua

Chemical and Biochemical Engineering Faculty Research & Creative Works

Heteromer star-shaped nanoparticles have the potential to carry out therapeutic agents, improve intracellular uptake, and safely release drugs after prolonged periods of residence at the diseased site. A one-step seed mediation process was employed using polylactide-co-glycolic acid (PLGA), polyvinyl alcohol (PVA), silver nitrate, and tetrakis(hydroxymethyl)phosphonium chloride (THPC). Mixing these reagents followed by UV irradiation successfully produced heteromer nanostars containing a number of arm chains attached to a single core with a high yield. The release of THPC from heteromer nanostars was tested for its potential use for breast cancer treatment. The nanostars present a unique geometrical design exhibiting a significant …


Metallization Of Self-Assembled Dna Templates For Electronic Circuit Fabrication, Bibek Uprety Jun 2017

Metallization Of Self-Assembled Dna Templates For Electronic Circuit Fabrication, Bibek Uprety

Theses and Dissertations

This work examines the deposition of metallic and semiconductor elements onto self-assembled DNA templates for the fabrication of nanodevices. Biological molecules like DNA can self-assemble into a variety of complex 2-D and 3-D architectures without the need for expensive patterning tools. In addition, self-assembled DNA templates can be designed to controllably place functional nanomaterials with molecular precision. These characteristics make DNA an attractive template for fabricating electronic circuits from biological molecules. However, electrically conductive structures are required for electronic applications. While metallized DNA nanostructures have been demonstrated, the ability to make thin, continuous wires that are electrically conductive still represents …


The Effects Of Tether Placement On Antibody Stability On Surfaces, Thomas A. Knotts, Rebecca W. Grawe Jun 2017

The Effects Of Tether Placement On Antibody Stability On Surfaces, Thomas A. Knotts, Rebecca W. Grawe

Faculty Publications

Despite their potential benefits, antibody microarrays have fallen short of performing reliably and have not found widespread use outside of the research setting. Experimental techniques have been unable to determine what is occurring on the surface of an atomic level, so molecular simulation has emerged as the primary method of investigating protein/surface interactions. Simulations of small proteins have indicated that the stability of the protein is a function of the residue on the protein where a tether is placed. The purpose of this research is to see whether these findings also apply to antibodies, with their greater size and complexity. …


Raman Spectral Variation For Human Fingernails Of Postmenopausal Women Is Dependent On Fracture Risk And Osteoporosis Status, J. R. Beattie, M. C. Caraher, N. M. Cummins, O. M. O'Driscoll, R. Eastell, S. H. Ralston, Mark R. Towler Jun 2017

Raman Spectral Variation For Human Fingernails Of Postmenopausal Women Is Dependent On Fracture Risk And Osteoporosis Status, J. R. Beattie, M. C. Caraher, N. M. Cummins, O. M. O'Driscoll, R. Eastell, S. H. Ralston, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Patients diagnosed with osteoporosis have reported loss of fingernail resilience as the disease progresses. Keratin is the predominant protein in human nail tissue, and its structure has been postulated to be different in fingernails clipped from subjects who have sustained fragility fractures and those who have not, which may offer a window into the donor's bone health. This study was designed to qualify these differences, which may lead to the development of a novel screening tool for fracture risk. Raman spectroscopy was used to measure the fingernails of 633 postmenopausal women who presented at six fracture clinics located across the …


Nanocomposite Thermite Powders With Improved Flowability Prepared By Mechanical Milling, Ci Huang May 2017

Nanocomposite Thermite Powders With Improved Flowability Prepared By Mechanical Milling, Ci Huang

Theses

Nanocomposite thermite powders are of interest to develop varieties of reactive parts and components. Manufacturing these components requires tailoring properties of the thermite powders such as their particle size distributions, particle shapes, and powder flowability. For example, an improved flowability is desired to use these powders as feedstock in additive manufacturing. Arrested reactive milling (ARM) offers a versatile and practical approach for preparing various nanocomposite thermites with fully dense particles, which will retain their structures and mixedness between reactive components while being stored, handled, and processed. However, ARM products usually have broad particle size distributions, rock-like particle shapes, and poor …


Thermal Swing Membrane Based Method For Co2 Capture From Flue Gas, Mukesh Kumar Kamad May 2017

Thermal Swing Membrane Based Method For Co2 Capture From Flue Gas, Mukesh Kumar Kamad

Theses

Carbon dioxide, a greenhouse gas and a major contributor to global warming, is released in large amounts by flue gases. To limit climate change, such CO2 emissions have to be reduced, CO2 captured and sequestered. Conventional monoethanolamine (MEA)-based absorption techniques are costly due to high capital cost and high energy consumption since the absorbent has to be regenerated at a high temperature ~ 120°C. A temperature swing membrane absorption (TSMAB) process was described by Mulukutla et al. (2015) using a novel membrane contactor, novel absorbents and a cyclic process. In this device, the absorbent is on the shell …


Power Dissipation And Power Correlations For A Retreatblade Impeller Under Different Baffling Conditions, Chadakarn Sirasitthichoke May 2017

Power Dissipation And Power Correlations For A Retreatblade Impeller Under Different Baffling Conditions, Chadakarn Sirasitthichoke

Theses

Glass-lined stirred reactors and tanks are commonly used in the pharmaceutical industry because of their corrosion resistance, ease of cleanliness and minimization of product contamination. Most industrial glass-lined tank reactors are provided with a torispherical tank bottom and a retreat curve impeller with low impeller clearance from the vessel bottom. The power, P, dissipated by the impeller is a critical process parameter to mixing processes to achieve the desired mixing effect, especially since the power per unit volume, P/V, directly controls mass transfer processes and other mixing phenomena. However, little information has been published about the power dissipation and the …


High Performance Lattice Boltzmann Method Yield-Stress Calculations Based On Intravital Images Of Clot Formation In Live Mice, Vishnu Deep Chandran May 2017

High Performance Lattice Boltzmann Method Yield-Stress Calculations Based On Intravital Images Of Clot Formation In Live Mice, Vishnu Deep Chandran

Theses

Thrombo-embolic infarction is the major cause of mortality and morbidity in the United States, causing over 1 million strokes, heart attacks and other life-threatening thrombotic events each year in the United States. Conversely, deficiencies in these processes result in severe bleeding risks. The ability to access hydrodynamics stresses at which thrombus structure is likely to embolize can provide insight into the thrombogenesis process. Interestingly, the viscoelastic behavior exhibited by the thrombus resembles that of a Bingham fluid - a material that behaves as a rigid body at low stresses but flows as a viscous fluid when the stress exceeds critical …


Investigation Of Nh3 And No Adsorption Over Cu/Sapo-34 And Cu/Aloo3 Catalysts For Nh3–Scr System, Basil Rawah May 2017

Investigation Of Nh3 And No Adsorption Over Cu/Sapo-34 And Cu/Aloo3 Catalysts For Nh3–Scr System, Basil Rawah

Theses

In this study, Copper supported on SAPO-34 molecular sieves or alumina is prepared via an incipient wetness impregnation method for ammonia selective catalytic reduction (NH3-SCR). These NH3-SCR catalysts are characterized by pulse chemisorption, temperature-programmed reduction (TPR), and temperature-programmed desorption (TPD) with three different conditions (NH3, NO, combined NH3-NO) to evaluate the adsorption of ammonia and nitric oxide. Cu/SAPO-34 catalyst has shown higher ammonia adsorption capacity compared to Cu/Al2O3 catalyst. The Cu/SAPO-34 adsorption is enhanced due to the strong acidity and high surface area of SAPO-34 molecular sieves. NO adsorption …


Cell Attachment To Alginate Hydrogel Structures, Sarah Livingston, Dr. Alonzo Cook May 2017

Cell Attachment To Alginate Hydrogel Structures, Sarah Livingston, Dr. Alonzo Cook

Journal of Undergraduate Research

One of the most pressing needs within the medical community is the demand for transplantable organs. On average, 22 people per day on average die waiting for a transplant. Even if a patient receives an organ, the risks associated with the transplant are high, from the immunosuppressant drugs required to the risk of Graft-versus-host disease (GvHD). If organs could be engineered using a patient’s own cellular material, transplants could take place without the risk of GvHD or the need for immunosuppressants. One of the keys to creating any organ is first building a vascular network that could provide vital nutrients …


A Solution To The Problems Of Heart Transpantation, Jeremy Struk, Alonzo Cook May 2017

A Solution To The Problems Of Heart Transpantation, Jeremy Struk, Alonzo Cook

Journal of Undergraduate Research

Ischemic Heart disease, according to the World Health Organization, is the leading cause of death in the USA and abroad.1 As a result of the high incidence of the disease and low transplant availability, the field of tissue engineering offers a promising solution. With the new developments in the field, many exciting treatments are available to help stem the tide of the disease, however; there is still a great need for more viable heart replacements to help patients with end stage heart failure. Tissue engineering offers the solution of creating hearts for patients in need that are constructed using the …


Re-Epithelialization Of Whole Porcine Kidney Scaffold, Evan M. Buckmiller, Alonzo D. Cook May 2017

Re-Epithelialization Of Whole Porcine Kidney Scaffold, Evan M. Buckmiller, Alonzo D. Cook

Journal of Undergraduate Research

An estimated 20 million adults (approximately 10% of all individuals over the age of 18) in the United States suffer from some level of chronic kidney disease (CKD), making CKD the 9th leading cause of death in the United States (1). The only successful treatment for end-stage renal failure is transplantation from a donor with similar blood antigen makeup, while living the remainder of their lives receiving immunosuppressive therapy. Unfortunately, individuals awaiting a kidney transplant outnumber viable donations. Scientists have been tasked with discovering and developing methods to answer this growing need. One promising method is the decellularization of porcine …


Continuous Ethanol Production From Synthesis Gas By Clostridium Ragsdalei In A Trickle-Bed Reactor, Mamatha Devarapalli, Randy S. Lewis, Hasan K. Atiyeh May 2017

Continuous Ethanol Production From Synthesis Gas By Clostridium Ragsdalei In A Trickle-Bed Reactor, Mamatha Devarapalli, Randy S. Lewis, Hasan K. Atiyeh

Faculty Publications

A trickle-bed reactor (TBR) when operated in a trickle flow regime reduces liquid resistance to mass transfer because a very thin liquid film is in contact with the gas phase and results in improved gas–liquid mass transfer compared to continuous stirred tank reactors (CSTRs). In the present study, continuous syngas fermentation was performed in a 1-L TBR for ethanol production by Clostridium ragsdalei. The effects of dilution and gas flow rates on product formation, productivity, gas uptakes and conversion efficiencies were examined. Results showed that CO and H2 conversion efficiencies reached over 90% when the gas flow rate was maintained …


Uncertainty Quantification And Propagation Of Errors Of The Lennard-Jones 12-6 Parameters For N-Alkanes, Richard A. Messerly, Thomas A. Knotts Iv, W Vincent Wilding May 2017

Uncertainty Quantification And Propagation Of Errors Of The Lennard-Jones 12-6 Parameters For N-Alkanes, Richard A. Messerly, Thomas A. Knotts Iv, W Vincent Wilding

Faculty Publications

Molecular simulation has the ability to predict various physical properties that are difficult to obtain experimentally. For example, we implement molecular simulation to predict the critical constants (i.e., critical temperature, critical density, critical pressure, and critical compressibility factor) for large n-alkanes that thermally decompose experimentally (as large as C48). Historically, molecular simulation has been viewed as a tool that is limited to providing qualitative insight. One key reason for this perceived weakness in molecular simulation is the difficulty to quantify the uncertainty in the results. This is because molecular simulations have many sources of uncertainty that propagate …


Preliminary Study Of Optimization Of Normal Pulse Voltammetry For Actinide Measurement In Molten Salt Electrorefiners Using Licl-Kcl-Ucl3-Mgcl2 As A Surrogate Salt, Chao Zhang, Devin Rappleye, Michael Simpson May 2017

Preliminary Study Of Optimization Of Normal Pulse Voltammetry For Actinide Measurement In Molten Salt Electrorefiners Using Licl-Kcl-Ucl3-Mgcl2 As A Surrogate Salt, Chao Zhang, Devin Rappleye, Michael Simpson

Faculty Publications

Normal pulse voltammetry has been applied and optimized to develop correlations between diffusional current and concentration for UCl3 and MgCl2 in molten eutectic LiCl-KCl. This method was selected to mitigate working electrode area growth in concentrated molten salt mixtures in which a fairly wide potential range is needed to analyze all actinides. MgCl2 has been selected as a surrogate for PuCl3 based on similar standard reduction potential. Diffusional current plateaus were successfully attained by adjusting the step size to 0.03 V. Relaxation time of 15 seconds was found to be sufficient to recover after each pulse. …


Computational Fluid Dynamics Modeling And Simulations Of Fast Fluidized Bed And Moving Bed Reactors For Chemical Looping Combustion, Mengqiao Yang May 2017

Computational Fluid Dynamics Modeling And Simulations Of Fast Fluidized Bed And Moving Bed Reactors For Chemical Looping Combustion, Mengqiao Yang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Chemical-looping combustion (CLC) is a next generation carbon capture technology with high efficiency and low cost. To assess the potential of this technology for industrial scale power plants, thousands of laboratory scale and many pilot-scale plants have been designed and tested. In recent years, to obtain a thorough understanding of the hydrodynamic behavior inside the reactors and chemical looping combustion process, high-fidelity numerical simulation using Computational Fluid Dynamics(CFD) have been performed. However, CFD simulations in the literature have been limited reported compared to the laboratory scale experiments.

In this thesis, cold flow simulations of a CLC fuel reactor are performed …


Desulfination By 2′-Hydroxybiphenyl-2-Sulfinate Desulfinase Proceeds Via Electrophilic Aromatic Substitution By The Cysteine-27 Proton, Inacrist Geronimo, Shawn R. Nigam, Christina M. Payne May 2017

Desulfination By 2′-Hydroxybiphenyl-2-Sulfinate Desulfinase Proceeds Via Electrophilic Aromatic Substitution By The Cysteine-27 Proton, Inacrist Geronimo, Shawn R. Nigam, Christina M. Payne

Chemical and Materials Engineering Faculty Publications

Biodesulfurization is an attractive option for enzymatically removing sulfur from the recalcitrant thiophenic derivatives that comprise the majority of organosulfur compounds remaining in hydrotreated petroleum products. Desulfurization in the bacteria Rhodococcus erythropolis follows a four-step pathway culminating in C–S bond cleavage in the 2′-hydroxybiphenyl-2-sulfinate (HBPS) intermediate to yield 2-hydroxybiphenyl and bisulfite. The reaction, catalyzed by 2′-hydroxybiphenyl-2-sulfinate desulfinase (DszB), is the rate-limiting step and also the least understood, as experimental evidence points to a mechanism unlike that of other desulfinases. On the basis of structural and biochemical evidence, two possible mechanisms have been proposed: nucleophilic addition and electrophilic aromatic substitution. Density …


Thermally Stable Support For Improved Synthetic Fuel Catalysts, Mark Lindsay, Dr. William Hecker, Dr. Morris Argyle May 2017

Thermally Stable Support For Improved Synthetic Fuel Catalysts, Mark Lindsay, Dr. William Hecker, Dr. Morris Argyle

Journal of Undergraduate Research

Fischer-Tropsch Synthesis (FTS) has attracted interest recently as large natural gas deposits have been discovered across the globe. FTS is a gas-to-liquid technology that produces fuels with far fewer sulfur or nitrogen impurities, making it an attractive cleaner alternative to petroleum fuels[1]. Cobalt is the preferred catalyst for FTS[2], but it must be supported to achieve optimal performance. Alumina and silica have been used independently as colbalt FTS supports[3-4], and in mixtures as supports for other processes, but mixed silica-alumina supports have not been studied for FTS applications[5]. The BYU Catalysis Lab has discovered a silica-alumina support (AlSi) with high …


Pore Functionalized Pvdf Membranes With In-Situ Synthesized Metal Nanoparticles: Material Characterization, And Toxic Organic Degradation, Hongyi Wan, Nicolas J. Briot, Anthony Saad, Lindell E. Ormsbee, Dibakar Bhattacharyya May 2017

Pore Functionalized Pvdf Membranes With In-Situ Synthesized Metal Nanoparticles: Material Characterization, And Toxic Organic Degradation, Hongyi Wan, Nicolas J. Briot, Anthony Saad, Lindell E. Ormsbee, Dibakar Bhattacharyya

Chemical and Materials Engineering Faculty Publications

Functionalized PVDF membrane platforms were developed for environmentally benign in-situ nanostructured Fe/Pd synthesis and remediation of chlorinated organic compounds. To prevent leaching and aggregation, nanoparticle catalysts were integrated into membrane domains functionalized with poly (acrylic acid). Nanoparticles of 16–19 nm were observed inside the membrane pores by using focused ion beam (FIB). This technique prevents mechanical deformation of the membrane, compared to the normal SEM preparation methods, thus providing a clean, smooth surface for nanoparticles characterization. This allowed quantification of nanoparticle properties (size and distribution) versus depth underneath the membrane surface (0–20 μm). The results showed that nanoparticles were uniformly …


Sub 2 Nm Particle Characterization In Systems With Aerosol Formation And Growth, Yang Wang May 2017

Sub 2 Nm Particle Characterization In Systems With Aerosol Formation And Growth, Yang Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Aerosol science and technology enable continual advances in material synthesis and atmospheric pollutant control. Among these advances, one important frontier is characterizing the initial stages of particle formation by real time measurement of particles below 2 nm in size. Sub 2 nm particles play important roles by acting as seeds for particle growth, ultimately determining the final properties of the generated particles. Tailoring nanoparticle properties requires a thorough understanding and precise control of the particle formation processes, which in turn requires characterizing nanoparticle formation from the initial stages. The knowledge on particle formation in early stages can also be applied …


Insulin, Glucose, And Β-Cell Diffusion Analysis, Matthew Usevitch, Alonzo Cook May 2017

Insulin, Glucose, And Β-Cell Diffusion Analysis, Matthew Usevitch, Alonzo Cook

Journal of Undergraduate Research

The purpose of this project is to further understand the function of extruded polytetrafluoroethylene (ePTFE) membranes in the pursuit of creating an implantable, removable pancreas device. This device would be filled with pancreas cells and automatically regulate blood sugar for patients with diabetes. Dr. Alonzo Cook’s lab is currently pursuing understanding the process of taking a patient’s own cells, reprogramming them into stem cells, and then differentiating them into pancreas cells. The device that is the end goal of this project is the main foreseen use of these differentiated pancreas cells. This project focuses on studying how essential nutrients diffuse …


Synthesis And Characterization Of Molybdenum Sulfide And For Hydrogen Evolution Reaction And Supercapacitor Applications, Zhuo Wang May 2017

Synthesis And Characterization Of Molybdenum Sulfide And For Hydrogen Evolution Reaction And Supercapacitor Applications, Zhuo Wang

Electronic Theses & Dissertations

To meet the constantly rising requirement of energy other than traditional fossil fuel and environment protection, it is a perfect time to development low cost, and efficient materials for clean energy production. Hydrogen generation by water splitting is one of the cleanest ways to produce cheaper energy. Hydrogen evolution reaction (HER) is one of the key steps in water splitting process. Ideally, the thermodynamic potential for HER should be at 0 V (vs. SHE). However, without an efficient catalyst, this reaction occurred at higher potential, called overpotential. A good HER catalyst is needed to lower the overpotential and hence to …


Differentiation Of Ipscs Into Cardiomyocytes Utilizing Extracellular Matrix, Arthur Castleton, Alonzo Cook May 2017

Differentiation Of Ipscs Into Cardiomyocytes Utilizing Extracellular Matrix, Arthur Castleton, Alonzo Cook

Journal of Undergraduate Research

According to the American Heart Association, Ischemic heart disease is the principal cause of death. Many potential therapies are being simultaneously explored and among the most promising is tissue engineering of cardiac scaffolds. In vitro culturing of mature cardiomyocytes has the potential to lay the foundation for products such as cardiac patches for treatment of early stages of Ischemic heart disease or atrial septal defects, and developing entire replacement hearts. However, cardiomyocyte cell culture and experimentation has encountered various difficulties; the inability to proliferate, incomplete maturation, and having a small window of functional contraction. Conversely, iPSCs can partially differentiate into …


Pluripotent Stem Cell (Ipsc) Differentiation To Kidney Phenotype With Conditioned Media Of Rctes, Angela Nakalembe, Dr. Alonzo Cook May 2017

Pluripotent Stem Cell (Ipsc) Differentiation To Kidney Phenotype With Conditioned Media Of Rctes, Angela Nakalembe, Dr. Alonzo Cook

Journal of Undergraduate Research

According to the latest U.S. Renal Data System Annual Data Report, more than 660,000 Americans are currently being treated for kidney failure, also called end stage renal disease (ESRD). The current treatment options, dialysis and kidney transplants, work well in some instances but have disadvantages, such as the inability to perform hormone regulation and potential organ rejection respectively.

The overall aim of our work is to create bioengineered kidneys that will provide alternative solutions to the current treatment methods without any of the drawbacks. New breakthroughs in the biomedical world support the theory that organs can be grown from cultured …


Biosensor System For The Detection Of Endocrine Disrupting Chemicals, Conner Earl, Bradley Bundy May 2017

Biosensor System For The Detection Of Endocrine Disrupting Chemicals, Conner Earl, Bradley Bundy

Journal of Undergraduate Research

Endocrine Disrupting Chemicals (EDCs) present problems worldwide and have been linked to cancer, developmental disorders, and other epigenetic complications. Many of these complications could be mitigated if not eradicated if these chemicals were better characterized and detectable, however an inexpensive, reliable and field deployable sensor for EDCs has yet to be developed. The purpose of this project was to explore the idea of an engineered Cell Free biosensor system that is an economic, viable method for the rapid detection of EDCs.


Portable Food & Water Sanitation By Means Of Energetic Photons, Jordan Argyle, Matthew Memmott May 2017

Portable Food & Water Sanitation By Means Of Energetic Photons, Jordan Argyle, Matthew Memmott

Journal of Undergraduate Research

At least 1 in 10 people across the globe do not have access to clean water.1 The World Health Organization considers food and drink contamination to be “the most widespread health problem in the contemporary world.”2 An estimated 600 million people fall ill from eating contaminated food or drinking contaminated water every year, of which nearly half a million die. Most of those illnesses are caused by pathogens rather than chemical contamination.3


Analysis Of Magnetic Resonance Imaging Of Peripheral Nerve Regeneration, Jaron Lundwall, Alonzo Cook May 2017

Analysis Of Magnetic Resonance Imaging Of Peripheral Nerve Regeneration, Jaron Lundwall, Alonzo Cook

Journal of Undergraduate Research

Due to accident-related neural damage, many people’s lives are impaired or limited in what they can do. Current medical practices are limited at helping distal and proximal nerve stubs regenerate. Many recent research studies have focused on trying to improve this problem by understanding how cut or crushed nerves heal. This study focused on helping these efforts by improving non-invasive analysis techniques of nerve growth. Magnetic Resonance Imaging (MRI) is one possible solution to creating a reliable analysis technique that in the future could be used on humans. We have shown that Magnetic Resonance Imaging can be used without invasive …


Characterization Of Polyester Polymer Concrete Material Properties, Robert Stevens, Dr. W. Spencer Guthrie May 2017

Characterization Of Polyester Polymer Concrete Material Properties, Robert Stevens, Dr. W. Spencer Guthrie

Journal of Undergraduate Research

The purpose of this project was to investigate selected material properties of polyester polymer concrete (PPC) using laboratory testing. PPC is a synthetic concrete that combines sand and coarse aggregate with a polyester resin binder that takes the place of conventional portland cement. PPC is commonly used as an overlay material on bridge decks. There is some ambiguity about several important mechanical properties of PPC, including coefficient of thermal expansion (CTE), degree of hardening, and modulus of elasticity. The objective of this research was to investigate the effect of temperature on these properties. The results of this research will help …


Methanol Steam Reforming: Na Doping Of Pt/Ysz Provides Fine Tuning Of Selectivity, Michela Martinelli, Gary Jacobs, Uschi M. Graham, Burtron H. Davis May 2017

Methanol Steam Reforming: Na Doping Of Pt/Ysz Provides Fine Tuning Of Selectivity, Michela Martinelli, Gary Jacobs, Uschi M. Graham, Burtron H. Davis

Center for Applied Energy Research Faculty and Staff Publications

In this work, we found that sodium doping can be used to improve CO2 selectivity for supported Pt catalyst during methanol steam reforming. These materials are usually very active in the low temperature range; however, they are characterized by high selectivity of CO, which is a poison in downstream polymer electrolyte membrane fuel cells (PEM-FC) application. With Na doping, we found that CO2 selectivity was higher than 90% when 2.5 wt.% of sodium was added to Pt/YSZ. We have speculated that the different product distribution is due to a different reaction pathway being opened for CH3OH …