Model Of A Tubular Perfusion Bioreactor Using Computational Fluid Dynamics.,
2015
University of Louisville
Model Of A Tubular Perfusion Bioreactor Using Computational Fluid Dynamics., Matthew James Robeson 1991-
Electronic Theses and Dissertations
Through recent years, many novel bioreactor designs for tissue engineering have emerged. The Tubular Perfusion System (TPS) is one such bioreactor for bone and cartilage tissue engineering. The TPS is a perfusion type bioreactor, in which media flows through a bed of scaffold beads. The advantage of this system over similar designs is that it requires no special fabrication techniques and operates at low pressure. Experimental trials have shown increased osteoblastic differentiation and mineralization of bone tissue grown using the TPS versus static culture. The effectiveness of the TPS in promoting osteoblastic differentiation is believed to be due to enhanced …
Plant-Level Dynamic Optimization Of Cryogenic Carbon Capture With Conventional And Renewable Power Sources,
2015
Brigham Young University
Plant-Level Dynamic Optimization Of Cryogenic Carbon Capture With Conventional And Renewable Power Sources, Seyed M. Safdarnejad, John Hedengren, Larry Lin Baxter
Faculty Publications
Increasing competitiveness of renewable power sources due to tightening restrictions on CO2 emission from fossil fuel combustion is expected to cause a shift in power generation systems of the future. This investigation considers the impact of the Cryogenic Carbon Capture™ (CCC) process on transitional power generation. The CCC process consumes less energy than chemical and physical absorption processes and has an energy storage capability that shifts the parasitic loss of the CCC process away from peak hours. The CCC process responds rapidly to the variation of electricity demand and has a time constant that is consistent with the intermittent …
Peptoid-Based Klvff Mimics: A Unique Approach To Alzheimer's Disease,
2015
University of Arkansas, Fayetteville
Peptoid-Based Klvff Mimics: A Unique Approach To Alzheimer's Disease, James Phillip Turner
Graduate Theses and Dissertations
Alzheimer’s disease (AD) is the leading form of dementia worldwide. AD patients experience a slow, gradual cognitive decline that includes loss of memory and behavioral stability as the disease progresses. Surprisingly, AD is the sixth leading cause of death in the United States and has had a profound impact on the U.S. economy. Though there are medications to help improve the quality of life of diagnosed patients for a period of time, there is still no cure for AD. AD is characterized by the build-up of amyloid plaques that develop from the aggregation of the amyloid beta protein (Aβ) in …
Hydrothermal Catalytic Liquefaction And Deoxygenation Of Biomass For Renewable Fuel Production,
2015
Old Dominion University
Hydrothermal Catalytic Liquefaction And Deoxygenation Of Biomass For Renewable Fuel Production, Sergiy Popov
Civil & Environmental Engineering Theses & Dissertations
In recent years, sub- and supercritical water technologies received an increasing attention because of the numerous advantages they offer for biomass converting into biofuels. Water at elevated temperatures and pressures provides an ideal medium for chemical transformations. It serves as a reactant, reaction medium, and catalyst that helps biomass compounds undergo hydrolysis, depolymerization, dehydration, decarboxylation, and condensation/repolymerization reactions. Biomass is the fourth largest source of energy in the world after coal, oil, and natural gas that has the potential to provide the large scale substitution of hydrocarbon-based liquid transportation fuels and minimize the environmental issues. Biomass typically contains 40-60% oxygen. …
Investigating The Impact Of Cryogenic Carbon Capture On Power Plant Performance,
2015
Brigham Young University
Investigating The Impact Of Cryogenic Carbon Capture On Power Plant Performance, Seyed M. Safdarnejad, L. Kennington, Larry Lin Baxter, John Hedengren
Faculty Publications
Cryogenic Carbon Capture (CCC) is a CO2 mitigation process that can be integrated into existing baseline and load following fossil-fueled power plants. This process consumes less energy than conventional chemical absorption and includes energy storage capability. The CCC process has a fast response time to load changes to allow higher utilization of intermittent renewable power sources to be used at a grid-scale level in the power sector. The impact of the CCC process on the performance and operating profit of a single fossil-fueled power generation unit is studied in this paper. The proposed system (power production from wind, coal, and …
Using Peptoids To Build Robust, Efficient Microarray Systems,
2015
University of Arkansas, Fayetteville
Using Peptoids To Build Robust, Efficient Microarray Systems, Dhaval Sunil Shah
Graduate Theses and Dissertations
Recent studies have shown microarrays to be indispensable for various biological applications, allowing for high-throughput processing and screening of biological samples such as RNA, DNA, proteins and peptides using a small sample volume (< 1 µL). Peptoids (poly-N-substituted glycine oligomers) can be used as a substitute for antibodies as capture molecules, as well as coatings for slides in antibody microarrays. The ease of synthesis of peptoids, high customizability with desired bioactivity, and speed of synthesis allows us to build a diagnostic system with a large dynamic range that can detect biomolecules from a minimal sample size. In this study, peptoid-based antibody mimics are designed to have both structural and functional features similar to those of antibodies, including a stable constant region (scaffolding) and a variable region for protein recognition. Peptoids previously screened via combinatorial library synthesis to be specific to bind Mdm-2 (mouse double minute 2 homolog) and GST (gluthathione S-transferase), have been synthesized. The protein recognition peptoids have been conjugated to PEG (polyethylene glycol) molecules with modified end groups; an amine group on one end that allows for immobilization and orientation on the slide, and an azide group on the other end that will allow for attachment to the peptoid through “click chemistry”. The number of capture molecules printed on the slides can be increased by making the available surface area of the slide larger via coating with microspheres. We have determined that partially water soluble peptoids that are also helical, can self-assemble into microspheres. Sequences have been developed that can consistently produce uniform microsphere coatings on slides that increase the overall surface area. A high surface area corresponds to a higher number of binding sites, and therefore a more sensitive system. The work done has shown that slides may be successfully coated in order to potentially improve the detection system.
A Computational Study Of The Potential For Lng Tanker Polystyrene Foam Insulation Failure Under Fire Exposure,
2015
University of Arkansas, Fayetteville
A Computational Study Of The Potential For Lng Tanker Polystyrene Foam Insulation Failure Under Fire Exposure, Jeffrey David Martinez
Graduate Theses and Dissertations
Liquefied natural gas is shipped across the oceans in large marine carriers. The carriers house the LNG using several different insulation systems. One of these systems involves large aluminum spheres insulated with polystyrene foam. Polystyrene foam is very susceptible to heat degradation. This raised issues as to the extent of possible insulation failure caused by a large ship fire. Experiments were done investigating the nature of polystyrene’s thermal degradation, notably by Brauman, Chen, and Matzinger and Butler. A large scale investigation was also performed by Sandia National Laboratory. However, computational modeling of the degradation was lacking. This work set out …
Electromagnetic Induction By Ferrofluid In An Oscillating Heating Pipe,
2015
Mississippi State University
Electromagnetic Induction By Ferrofluid In An Oscillating Heating Pipe, John Gabriel Monroe, Erick S. Vasquez, Zachary S. Aspin, Keisha B. Walters, Matthew J. Berg, Scott M. Thompson
Chemical and Materials Engineering Faculty Publications
No abstract provided.
Synthesis Of Graphene Wrapped Li-Rich Layered Metal Oxide And Its Electrochemical Performance,
2015
Department of Chemistry, Fudan University, Shanghai 200433, China;
Synthesis Of Graphene Wrapped Li-Rich Layered Metal Oxide And Its Electrochemical Performance, Meng-Yan Hou, Ke Wang, Xiao-Li Dong, Yong-Yao Xia
Journal of Electrochemistry
In present work, lithium-rich layered transition metal oxide (LLO) was synthesized by a co-precipitation method in combination with a solid-state reaction. The graphene wrapped Li-rich layered oxide composite (LLO/Gra) was obtained by sintering the LLO/GO composite at 300 oC for 30 min in an air. The morphologies and the electrochemical performances were characterized by means of SEM, TEM, XRD, XPS, EIS and charge/discharge tests. The results indicated that the LLOe particles were uniformly wrapped with graphene. The resulting material exhibited better rate capability than that of pristine LLO since the wrapped graphene demonstrated the enhanced electronic conductivity. Accordingly, the …
Enhancing Stability Of Pem Fuel Cell Catalysts Via Support Changing,
2015
School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;
Enhancing Stability Of Pem Fuel Cell Catalysts Via Support Changing, Xiao-Hong Xie, Zi-Dong Wei
Journal of Electrochemistry
The Pt/C catalyst with highly dispersed Pt nanoparticles supported on carbon has been widely used as the state-of the-art catalyst in proton exchange membrane fuel cells (PEMFCs), while the durability of Pt/C is one of the major barriers for large-scale applications of PEMFCs. Thus, enhancing the stability of Pt/C has been a hot issue in this field. In this review, we summarize the recent progress in enhancing the catalyst stability in the view of support material. The future prospects of the PEMFCs catalyst should focus on adopting more stable supports or strengthening the interactions between Pt and supports.
Pt/C Modified Proton Exchange Membrane For Improved Fuel Cell Performance,
2015
Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
Pt/C Modified Proton Exchange Membrane For Improved Fuel Cell Performance, Zhi Cui, Chao Wang, Shui-Yun Shen, Feng-Jing Jiang, Jun-Liang Zhang
Journal of Electrochemistry
The property of proton exchange membrane greatly affects the performance of proton exchange membrane fuel cells (PEMFC). During the operation of a PEMFC, the water produced at the cathode, the water vapor from the humidified feed gas and the water migrated by electro-dragging will reach a balance in the membrane and determine the resistance of PEMFC, and thus affect the performance of PEMFC. Normally, the PEMFC performance strongly depends on the relative humidity of the feed gas, and the performance decreases at lower humidity as a result of lower proton conductivity of the membrane. In this paper, we proposed to …
Sacrificial Amphiphiles: Eco-Friendly Chemical Herders As Oil Spill Mitigation Chemicals,
2015
CUNY City College
Sacrificial Amphiphiles: Eco-Friendly Chemical Herders As Oil Spill Mitigation Chemicals, Deeksha Gupta, Bivas Sarker, Keith Thadikaran, Vijay John, Charles Maldarelli, George John
Publications and Research
Crude oil spills are a major threat to marine biota and the environment. When light crude oil spills on water, it forms a thin layer that is difficult to clean by any methods of oil spill response. Under these circumstances, a special type of amphiphile termed as “chemical herder” is sprayed onto the water surrounding the spilled oil. The amphiphile forms a monomolecular layer on the water surface, reducing the air–sea surface tension and causing the oil slick to retract into a thick mass that can be burnt in situ. The current best-known chemical herders are chemically stable and nonbiodegradable, …
The Electroreduction Of Carbon Dioxide On Porous Copper Nanoparticles,
2015
University of New Mexico
The Electroreduction Of Carbon Dioxide On Porous Copper Nanoparticles, Monica Alisa Padilla
Chemical and Biological Engineering ETDs
Copper nanoparticles of porous, controlled structure were synthesized using the sacrificial support method (SSM). The precursor weight percent (wt%) of copper (Cu) and fumed silica (EH-5) was varied to determine the optimum ratio for this material. The precursors were reduced at i) 350°C in a 7% H2 atmosphere and ii) at 250°C in a 100% H2 atmosphere. The specific surface areas of the nanoparticles was measured by Brunauer-Emmett-Teller N2 absorption. The morphologies and widths of the nanoparticles were confirmed by imaging the nanoparticles by scanning electron microscopy (SEM). The bulk composition of the nanoparticles was determined by X-ray diffraction (XRD). …
Analysis Of Particle Transport And Deposition Of Micron-Sized Particles In A 90° Bend Using A Two-Fluid Eulerian–Eulerian Approach,
2015
University of Dayton
Analysis Of Particle Transport And Deposition Of Micron-Sized Particles In A 90° Bend Using A Two-Fluid Eulerian–Eulerian Approach, Erick S. Vasquez, Keisha B. Walters, D. Keith Walters
Chemical and Materials Engineering Faculty Publications
Two-phase flows involving dispersed particle and droplet phases are common in a variety of natural and industrial processes, such as aerosols, blood flow, emulsions, and gas-catalyst systems. For sufficiently dilute particle/aerosol phases, a simplified one-way coupling is often assumed, in which the continuous primary phase is unaffected by the presence of the dispersed secondary phase and standard CFD methods can be applied. To predict the transport and deposition of the particle phase, typically a Lagrangian particle-tracking or Eulerian one-fluid/two-phase drift-flux approach is used. Here, a full two-fluid Eulerian modeling approach is presented for coarse particles (>1 μm), in which …
The Nucleation And Growth Of Nanoparticles For Heterogeneous Catalysis,
2015
University of New Mexico
The Nucleation And Growth Of Nanoparticles For Heterogeneous Catalysis, Angelica Benavidez
Chemical and Biological Engineering ETDs
These studies investigate the nucleation and growth of nanoparticles and how their interaction with a support affects their reactivity as a heterogeneous catalyst. As capabilities in both synthesis methods and characterization methods advance, the use of nanoparticles and sub-nanometer species are more commonly used. These small particles introduce new factors that can cause differences in reactivity. Various catalyst synthesis methods are employed to deposit mono-dispersed particles on different oxide and carbon supports. Electron microscopy is used to study nanoparticle sintering and the careful tracking of individual particles gives insight into growth mechanisms. X-ray absorption spectroscopy measurements are used to characterize …
Morphology And Magnetic Properties Of Sulfonated Poly[Styrene-(Ethylene/Butylene)-Styrene]/Iron Oxide Composites,
2015
Molecular Rebar Design, LLC
Morphology And Magnetic Properties Of Sulfonated Poly[Styrene-(Ethylene/Butylene)-Styrene]/Iron Oxide Composites, Sateesh K. Peddini, Huy N. Pham, Leonard Spinu, James L. Weston, David E. Nikles, Kenneth A. Mauritz
Faculty Publications
α-Fe2O3 structures were initiated in the sulfonated polystyrene block domains of poly[styrene–(ethylene/butylene)–styrene] (SEBS) block copolymers via a domain-targeted in-situ chemical precipitation method. The crystal structure of these particles was determined using wide-angle X-ray diffraction and selected area electron diffraction using a transmission electron microscope (TEM). TEM revealed that for less sulfonated SEBS (10 mole%), nanoparticles were aggregated with aggregate size range of 100–150 nm whereas for high sulfonation (16 and 20 mole% sSEBS) there were needle-like structures with length and width of 200–250 nm and 50 nm, respectively. Dynamic mechanical analyses suggest that initial iron oxide nanoparticle …
Advances In Catalyst Deactivation And Regeneration,
2015
Brigham Young University - Provo
Advances In Catalyst Deactivation And Regeneration, Calvin H. Bartholomew, Morris D. Argyle
Faculty Publications
Catalyst deactivation, the loss over time of catalytic activity and/or selectivity, is a problem of great and continuing concern in the practice of industrial catalytic processes. Costs to industry for catalyst replacement and process shutdown total tens of billions of dollars per year. While catalyst deactivation is inevitable for most processes, some of its immediate, drastic consequences may be avoided, postponed, or even reversed through regeneration.
Astrocyte Response To Nanoscale Topography On Anodized Alumina Surfaces,
2015
Missouri University of Science and Technology
Astrocyte Response To Nanoscale Topography On Anodized Alumina Surfaces, D. Ganguly, C. D.L. Johnson, D. A. Borca-Tasciuc, R. J. Gilbert
Chemical and Biochemical Engineering Faculty Research & Creative Works
The Astrocytes are one of the most important and abundant resident glial cells of the central nervous system (CNS). They play a critical role in the foreign body response, by participating in the formation of the glial scar sunouncling implants. As part of the effort to minimize the foreign body response, biomaterials strategies einployiug engineered surfaces topographies are being explored. In this context, we have investigated the response of astrocytes to surface topography of alumiua, a material used in CNS applications. Specifically, astrocytes were seeded oil alumina surfaces with nanopores 20 nm and 100 nm in diameter, respectively. Pore-free alumina …
Effects Of Strontium Substitution On Bioactivity Of Hydroxyapatite,
2015
Missouri University of Science and Technology
Effects Of Strontium Substitution On Bioactivity Of Hydroxyapatite, Chokchai Yatongchai, Lana M. Placek, Mark R. Towler, Anthony W. Wren
Chemical and Biochemical Engineering Faculty Research & Creative Works
Effect of strontium (Sr) substitution on bioactivity of hydroxyapatite (HA) was investigated. The substitution of Sr2+ for Ca2+ in the HA lattice increases biodegradability of Sr-substituted HA (Sr-HA) and accelerates the formation of apatite crystals on the Sr-HA surface. Moreover, the dissolution products from HA and Sr-HA samples are not cyto-toxic.
Analysis Of Neurite Outgrowth On Electrospun Fiber Scaffolds In The Presence Of Blebbistatin And Paclitaxel,
2015
Missouri University of Science and Technology
Analysis Of Neurite Outgrowth On Electrospun Fiber Scaffolds In The Presence Of Blebbistatin And Paclitaxel, A. R. D'Amato, N. J. Schaub, C. D.L. Johnson, J. Cardenas, R. J. Gilbert
Chemical and Biochemical Engineering Faculty Research & Creative Works
In an attempt to increase the rate of neurite extension from E9 chick embryo dorsal root ganglion (DRG) on electro spun fiber scaffolds we experimented with two drugs that have been used previously to affect neuronal growth. Blebbistatin and paclitaxel were added to DRG cultured on electro spun fibers in an attempt to increase the rate of neurite extension along fibrous scaffolds. Blebbistatin increased the length of neurites extending from the DRG explant in comparison to the drug-free control group. In contrast, paclitaxel completely eliminated all neurite extension from the DRG explant when compared to the control. A third treatment …
