Chemical Engineering Commons^™

Impact Of Nafion Loading And Anion Adsorption On The Synthesis Of Pt Monolayer Core-Shell Catalysts, Lijun Yang, Dustin Banham, Elod Gyenge, Siyu Ye

Journal of Electrochemistry

Carbon supported palladium (Pd) nanoparticles were used as a model core material for the synthesis of platinum (Pt) monolayer core-shell catalysts using rotating disk electrode method and a copper (Cu) under potential deposition technique. The impact of Nafion on the synthesis process was revealed by electrochemical testing with various Nafion contents. The existence of Nafion influenced the Cu under potential deposition, galvanic replacement and eventually the oxygen reduction reaction activity of the core-shell catalyst. However, as long as the Nafion content was less than 5 wt% in the test film, adding Nafion could help to bind catalyst onto the surface …

Comparison Of Oxygen Reduction Reaction Activity Of Pt-Alloy Nanocubes, Yongan Tang, Lin Dai, Shouzhong Zou

Journal of Electrochemistry

Alloying Pt with the first row non-noble transition metals has been demonstrated to increase the catalytic activity toward oxygen reduction reaction (ORR), which is the cathode reaction of the proton exchange membrane fuel cells (PEMFCs) and metal-air batteries. However, how much the ORR activity improvement comes from the alloying elements remains controversial. In this paper, the nanocubes of PtMn, PtFe, PtCo, and PtNi with the similar size and composition were prepared and their ORR activities were explored, in order to investigate the effects of alloying elements on the catalytic activity. The use of cubic shape particles minimizes the contribution to …

Electrodeposition Of Ruo2 Layers On Tio2 Nanotube Array Toward Co2 Electroreduction, Bei Jiang, Lina Zhang, Xianxian Qin, Wenbin Cai

Journal of Electrochemistry

RuO₂/TiO₂ composite materials have multitude of electrocatalytic applications including but not limited to CO₂ reduction reaction (CO₂RR). RuO₂/TiO₂ electrodes were previously prepared by repetitive coating and thermal decomposition (TD) of a Ru(III) precursor solution on Ti substrate. In this work, electrochemical potential cycling is applied to deposit amorphous RuO₂ (α-RuO₂) layers onto TiO₂ nanotube array (TNA) (RuO₂^CV/TNA) preformed on Ti foil. SEM, GIXRD, and voltammetry are applied to characterize the structures of the resulting RuO₂^CV/TNA. Ru loading on the RuO_{2 …}

Conference Program, Antonio Moreira, David Robinson

Regulatory Sciences for Biologics and Vaccines: Accelerating Development and Enabling Manufacturing Innovation

No abstract provided.

Design Of 3d Macroporous Inverse Opal Tio2 Binary And Ternary Composites Sensitized With Gold Nanoparticles And Cds Quantum Dots For Photocatalysis, Daniel A. Corella

Master of Science in Chemical Sciences Theses

Materials composed of titanium (IV) oxide (TiO₂) have received enormous scientific interest due to titania’s abundance, non-toxicity, and photocatalytic proficiency, however its large band gap limits its applicability under ambient conditions. Various attempts have been made to incorporate titania into composite systems to sensitize it for activity under a broader range of wavelengths. One such method includes utilizing narrow band gap semiconductors to form an electron transfer process analogous to photosynthesis referred to as a Z-scheme. Z-scheme systems can catalyze the decomposition of aqueous pollutants via generation of reactive oxygen species after input of sunlight. This work reports …

Probing The Effects Of Surface Hydrophobicity And Tether Orientation On Antibody-Antigen Binding, Derek B. Bush, Thomas A. Knotts Iv

Faculty Publications

Antibody microarrays have the potential to revolutionize molecular detection for many applications, but their current use is limited by poor reliability, and efforts to change this have not yielded fruitful results. One difficulty which limits the rational engineering of next-generation devices is that little is known, at the molecular level, about the antibody-antigen binding process near solid surfaces. Atomic-level structural information is scant because typical experimental techniques (X-ray crystallography and NMR) cannot be used to image proteins bound to surfaces. To overcome this limitation, this study uses molecular simulation and an advanced, experimentally validated, coarse-grain, protein-surface model to compare fab-lysozyme …

Sophorolipid Butyl Ester Diacetate Does Not Affect Macrophage Polarization But Enhances Astrocytic Glial Fibrillary Acidic Protein Expression At Micromolar Concentrations In Vitro, Alexis M. Ziemba, Manoj K. Gottipati, Filbert Totsingan, Cheryl M. Hanes, Richard A. Gross, Michelle R. Lennartz, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Peritoneal macrophages (PMACs) and spinal cord astrocytes were exposed to varying concentrations of soluble sophorolipid butyl ester diacetate (SLBEDA) in vitro. Macrophages and astrocytes demonstrated no decrease in viability in response to SLBEDA. Studying pro- and anti-inflammatory genes, PMACs did not show a shift toward a pro-inflammatory phenotype. However, at higher concentrations (3 and 30 μM), astrocytes showed an increase in their expression of glial acidic fibrillary protein. This novel category of compounds poses low risk to PMAC and astrocyte viability; however, the effect on PMAC polarization and astrocyte reactivity requires more elucidation.

New Work Center Optimization, Clarissa Stanton

Honors Theses

No abstract available.

Safety Analysis Of A Flashing Drum Steam Generation System, Jacob Ladd, Cade Memmott

Journal of Undergraduate Research

The goal of the Integral, Inherently Safe Light Water Reactor (I2S-LWR) Research Project is to design a more inherently safe reactor. This reactor is capable of cooling the core with no external power and no operator action.[1] In the I2S-LWR design, micro-channel heat exchangers (MCHX) facilitate heat transfer from the reactor to the steam generation system (SGS), where steam is used to produce electricity.^{1, 2}

The I2S-LWR design requires the use of a “flashing” drum to produce steam, and the flashing drum and its impact on the SGS must be evaluated for safety before it can be incorporated into …

Investigation Of Copper Catalysts For Propylene Epoxidation, Hayden Fowler, Zheng Lu

Research Horizons Day Posters

No abstract provided.

Computer Simulation Of Flexiblity And Inertial Effects On Self-Propelled Swimming Bodies, Ye Luo, Tai-Hsien Wu

Research and Creative Activities Poster Day

In this research, a numerical simulation method is employed to simulate a flapping movement for a flexible slender swimmer in a fluid. Our objective is to study dynamic behaviors of the flapping movement. Fig. 1 shows a sketch of the simulation: the leading edge of the swimming body is swung in the vertical direction to generate a horizontal thrust force, which drives the body itself to cruise in the horizontal direction in a fluid. The simulation is based on a combination of three numerical methods: the Lattice Boltzmann Method (LBM), Lattice Spring Model (LSM), and Immersed Boundary Method (IBM). The …

Shear Driven Micro-Fluidic Pump For Cardiovascular Applications, Nihad E. Daidzic

Aviation Department Publications

A valveless shear-driven micro-fluidic pump design (SDMFP) for hemodynamic applications is presented in this work. One of the possible medical and biomedical applications is in-vivo hemodynamic (human blood circulation) support/assist. One or more SDMFPs can be inserted/implanted into vascular lumens in a form of a stent/duct in series and/or in parallel (bypass duct) to support blood circulation in-vivo. A comprehensive review of various micro-pump designs up to about mid 2000’s is given in [1,2]. Many of micropump designs considered are not suitable for in-vivo or even in-vitro medical/biomedical applications.

Operating principles, design, and SDMFP features are given in [3]. A …

Activity Of Pgm-Free Electrocatalysts For Oxygen Reduction Reaction: Ph And Co-Catalysis Effects, Mario Santiago Rojas Carbonell 8148369

Chemical and Biological Engineering ETDs

Fuel cells offer a source to the current and always increasing demand for electric power. But as any new technology, there are challenges that need to be addressed to render it feasible for the market place. One of this challenges is finding the appropriate materials to catalyze the oxygen reduction reaction (ORR) that occurs in the cathode. Oxygen is used as an oxidant in a significant portion of the fuel cells due to its readily availability and high reduction potential. Now, one the bottlenecks that stops the large-scale adoption is the expensive and rare metals that have been used as …

Bulletproof Vests/Shields Prepared From Composite Material Based On Strong Polyamide Fibers And Epoxy Resin, Hany A. Elazab Dr

Chemical Engineering

Fiber reinforced plastics (FRP) have arisen as a main class of structural materials having high strength and light weight implemented in a large scale of different applications. This paper performs a comparison between the enhanced properties of Kevlar 49 fiber and Twaron CT 704 reinforced with epoxy resin to obtain an efficient, light weight and slim body armor capable of resisting high speed projectiles (9mm bullets). Reinforcing the fabrics adds extra strength to the fabrics instead of using several unreinforced fabrics which increases the weight, thickness and the cost of the final product. The response of the prepared composite material …

Molecular-Size Selective Zeolite Membrane Encapsulated Novel Catalysts For Enhanced Biomass To Liquid (Btl) Processes, Ummuhan Cimenler

USF Tampa Graduate Theses and Dissertations

80% of energy usage in the word comes from fossil fuels (coal, oil, natural gas) and among the fossil fuels, oil is the most consumed energy source especially in transportation. However, due to concerns about energy demand and energy sustainability, global warming and dependency on foreign oil, generation of renewable fuels is crucial for transportation. Biomass to Liquid (BTL) is a promising process available to produce renewable liquid fuels. BTL fuels have great potential to meet the growing demand for liquid fuels, mitigating climate change, and providing value to rural areas. However, there are two major challenges with biofuels produced …

An Expedited, Regiospecific Para-Bromination Of Activated Aryls, Kathryn E. Dudley

Masters Theses & Specialist Projects

Electrophilic Aromatic Substitution (EAS) is one of the most frequently used aryl substitution methods. Aside from the fact that most EAS reactions require an acid and an oxidizer to proceed, the reactions involving activated aryls typically produce a mixture of ortho- and para- products as well as an ortho-/para- disubstituted product. Regiospecificity in aromatic substitution is key in the production of many compounds in a variety of disciplines. Since EAS is one of the most often used substitution methods, it is extremely important to develop an efficient method for regiospecific substitutions. Previous research developed a method of ortho-substitution by using …

Synthesis, Characterization, And Properties Of Graphene-Based Hybrids With Cobalt Oxides For Electrochemical Energy Storage And Electrocatalytic Glucose Sensing, Sara C. Botero Carrizosa

Masters Theses & Specialist Projects

A library of graphene-based hybrid materials was synthesized as novel hybrid electrochemical electrodes for electrochemical energy conversion and storage devices and electrocatalytical sensing namely enzymeless glucose sensing. The materials used were supercapacitive graphene-family nanomaterials (multilayer graphene-MLG; graphene oxide-GO, chemically reduced GO-rGO and electrochemical reduced GOErGO) and pseudocapacitive nanostructured transition metal oxides including cobalt oxide polymorphs (CoO and Co3O4) and cobalt nanoparticles (CoNP). These were combined through physisorption, electrodeposition, and hydrothermal syntheses approaches. This project was carried out to enhance electrochemical performance and to develop electrocatalytic platforms by tailoring structural properties and desired interfaces. Particularly, electrodeposition and hydrothermal synthesis facilitate chemically-bridged …

Modeling The Effect Of Methane Vs. Carbon Dioxide Injection On Oil Recovery: Case Study: The East Vacuum Grayburg-San Andres Unit, Lea County, New Mexico, Charles Ohalekwu

Graduate Theses & Non-Theses

This project aims to determine if methane (CH4) injection is more effective and economical than carbon dioxide (CO2) injection in a conventional dolomite reservoir by using the East Vacuum Grayburg-San Andres Unit (EVGSAU), Lea County, New Mexico as a model. This was done by simulating a CH4 and CO2 injection system and estimating the economics for each. CH4 injection has not been done at the EVGSAU, however CO2 has been used as a method of enhanced oil recovery.

The EVGSAU is located on the eastern side of the Vacuum Field, approximately 15 miles northwest of Hobbs in Lea County, New …

Technical Feasibility Of Selectively Separating Rare Earth Elements By Vapor Phase Extraction And Condensation, Katie Lyons

Graduate Theses & Non-Theses

Experiments were performed to evaluate the technical feasibility of selectively separating selected rare earth halides (bromides and chlorides) using a volatilization and condensation technique. Initially, optimum chloridizing and bromidizing roast parameters were secured in studies performed on reagent grade rare earth oxide samples and subsequently confirmed in tests performed on mineral ore and concentrate samples. The volatilization and condensation experiments were performed by placing the subject rare earth halide samples in an argon-purged multiple-zone tube furnace wherein the temperature profile was controlled to establish separate vaporization and condensation regions. Following each experiment, condensate and solid residue samples were analyzed to …

The Impact Of A Dynamic Environment On Deposition And Cellular Response To Silver Nanoparticles, Robert F. Uhrig

Honors Theses

Silver nanoparticles (AgNPs) are utilized in many different applications, such as an antibacterial agents or as protective coating against ultraviolet light. However, these AgNPs are known to cause potentially harmful biological effects, including toxicity, induction of stress, and immune activation. In this study, the effects of AgNPs on a human lung cell model were examined within both a static and dynamic environment. Most NP-based research is carried out in static environments, but do not accurate reflect dynamic physiological conditions. Dynamic fluid movement was introduced to the cell culture through the use of a multi-channel peristaltic pump. To further characterize the …