Chemical Engineering Commons^™

Synthesis Of Biologically-Inspired Nanofiltration Membranes Using Protected, Mutated, And Simulated Aquaporins, Priyesh Ashokrao Wagh

Theses and Dissertations--Chemical and Materials Engineering

Gram-negative bacterial cells are surrounded by a cell membrane which protects the cell and controls the transport of nutrients and waste products in and out of the cells at a fast rate. This rapid transport of nutrients and wastes through the cell membrane is made possible by channel proteins called porins. Various types of porins present in the cell membrane have specific functions depending on their selectivity towards different nutrients, and channel proteins selective towards water are called aquaporins. These proteins restrict the passage of all entities except water molecules and they provide a fast transport rate of water molecules …

Surface Functionalization Via Photoinitiated Radical Polymerization For Rare Cell Isolation And Mechanical Protection, Calvin Frank Cahall

Theses and Dissertations--Chemical and Materials Engineering

Surface functionalization of living cells for cell therapeutics has gained substantial momentum in the last two decades. From encapsulating islets of Langerhans, to cell laden gels for tissue scaffolds, to individual cell encapsulation in thin hydrogels, to surface adhesives and inert surface camouflage, modification of living cell surfaces has a wide array of important applications. Here we use hydrogel encapsulation of individual cells as a mode of protection from mechanical forces for high throughput cell printing, and chemical stimuli for the isolation of rare cells in blood.

In the first study, we review methods of surface functionalization and establish a …

The Role Of Microenvironment Reagent Solubility On Reaction Kinetics Of 4-Nitrophenol Reduction, Michael P. Zeevi, Andrew Harrison, Christina Tang

UROP Posters

The Role of Microenvironment Reagent Solubility on Reaction Kinetics of 4-Nitrophenol Reduction

Michael Zeevi¹ with Andrew Harrison¹ and Christina Tang, PhD¹

¹Department of Chemical and Life Science Engineering, VCU School of Engineering

Introduction: Nanoparticles are of increasing interest due to their high surface area to volume ratio, as well as that they enable fine-tuning of the reaction microenvironment. Through flash nanoprecipitation, core-shell polymer nanoreactors were formed by directed self-assembly. Using the reduction of 4-nitrophenol as a model reduction reaction, we investigated the effect of reagent solubility in the nanoreactor microenvironment’s on nanoreactor kinetics.

Methods: The standard …

Effects Of Predation On The Biochemical Constituents Of The Bleached Soft Coral Sinularia Polydactyla, Carley Elizabeth Cole

Honors Theses

Climate change can indirectly affect the level of predation on soft corals. As sea temperatures rise, more and more bleaching events are occurring, which can affect the production of chemical defenses and the concentrations of the biochemical constituents that make up the soft corals. These changes may make the soft corals more attractive to predators. This phenomenon is suggested by the environmental stress theory (EST), which states that under stressful conditions, more of an organism's energy is allocated to survival rather than to other factors, such as reproduction or predator deterrence. To test the effect of predation on already bleached …

Technique For The Synthesis Of Difluorinated Organic Molecules Using Magnesium Bases, Cassidy S. Baldwin

Honors Theses

The presence of fluorine in organic molecules can confer biological advantages which are often exploited in drug development. For example, fluorine has been shown to limit drug metabolism and enhance drug distribution. However, the development of fluorinated pharmaceutics poses synthetic challenges. These challenges are especially pronounced when developing molecules with a difluoromethyl group. One difluoromethyl functional group of particular interest is the α,α-difluoro-β-amino carbonyl group, which has been seen in potential drug leads. The previous methods of accessing this group are inefficient and complex. The goal of this project was to develop a new technique to access this group by …

Inhibition Of Blood Coagulation Factor Xii: Evaluation Of Flavonoids As A Drug Candidate, Betsy Crosswhite

Honors Theses

This study investigated natural product inhibitors of blood coagulation Factor XII (FXII). FXII initiates the Kallikrein Kinin-System (KKS) within the intrinsic coagulation pathway. Increased expression of this system leads to proinflammatory and procoagulant activities. Inflammation occurs through downstream activation in the KKS. Following the activation of FXII-dependent pathway, bradykinin (BK) binds to the BK receptor 2 (B2) and produces inflammatory signaling. Abnormally increased BK can result in life threatening Hereditary Angioedema (HAE), characterized by severe reoccurring swelling. FXII is critical for pathogenic thrombosis, but is dispensable for hemostasis. This unique property of FXII makes it an attractive drug target. We …

Perceptions Regarding Concussions In Collegiate Football At The University Of Mississippi, Madison Frerker

Honors Theses

Concussions are a form of mild traumatic brain injury (mTBI) that can occur from any force to the head or body that causes the brain to move within the skull. Concussions are common in the sport of football due to the highly physical nature of the sport, and injured athletes can experience a wide array of symptoms. Like other players participating with powerhouse football programs, those at the University of Mississippi are at risk of concussion throughout their collegiate career. Whether players and fans perceive the risks of concussion equally has not been previously studied. Considering the passionate history of …

Development Of A Scn1a Null Zebrafish Model For Screening Potential Anti-Epileptic Natural Products, Patricia Ann Lipson

Honors Theses

Epilepsy affects around 50 million people in the world. Thus, it is imperative that new more effective and safe treatments be found. This study was designed to use zebrafish to screen potential anti-epileptic natural products. We utilized two scn1Lab null zebrafish models (morpholino-injected fish where scn1Lab was transiently knocked down and a transgenic scn1Lab -/- fish line). Alternatively, we used AB wildtype fish to test compounds in a chemically-induced seizure model. Natural compounds including cannabidiol, CBD, and Tapinanthus globiferous, TG, extracts were screened for their anti-seizure activity. When scn1Lab -/- fish were treated with CBD (0.075 and 0.3 mg/L) from …

A Case Study On The Design And Optimization Of An Ethylbenzene Production Plant, William Grafton Peaster

Honors Theses

This thesis will detail two goals of my capstone design project. The first goal is to simulate a given base case of a vapor phase reaction ethylbenzene production facility in PRO/II simulation software and discretely optimize the process in order to increase the profitability of the plant. The second goal is to develop a base case process flow diagram, stream tables, utility tables, and equipment tables for an ethylbenzene facility with liquid phase reactions. The base case simulation and optimization is a group task with my assigned group members in Ch E 451. The first part of this study looks …

Process Design And Optimization: Analysis Of An Ethylbenzene Production Plant, Jonathan Butler Vanveckhoven

Honors Theses

This thesis will cover the steps I took to evaluate an ethylbenzene production plant. I, along with my senior design team, was first tasked with optimizing a vapor-phase ethylbenzene production plant based off of a given base case. Our team was able to improve the net present value of the plant from -$4.8 million to $70.4 million through discrete optimization. After the vapor-phase plant was evaluated, I was tasked with creating a base case, liquid-phase ethylbenzene production plant. I explain the theory behind process flow diagram development, then explain how I produced the process flow diagram and stream table for …

Solvent And Concentration Effects Governing The Hierarchical Organization Of Asphaltenes: A Small-Angle X-Ray Scattering Study, Hasan Rejoanur Rahman

Open Access Theses & Dissertations

Asphaltenes are a group of planar molecules found in crude oil and are prone to aggregation which often causes blockage of pipes along the oil production stream resulting a huge economic downside. In an effort to understand the hierarchical organization of asphaltene in different solvents and concentrations, the solution structure of various asphaltene solutions were studied using small-angle x-ray scattering (SAXS). Solvents were chosen based on miscibility maps. Such maps are generated on the critical value of the solubility parameter difference between asphaltenes or asphaltene components, and a range of solvents. The critical factors that affect asphaltene and asphaltene component …

Sequence Effects On The Glass Transition Temperature, William Drayer

Williams Honors College, Honors Research Projects

Lithium ion batteries are widely used for the energy needs of portable electronic devices. Unfortunately, current liquid organic solvents used as the electrolytic portion of the battery have low thermal stability, resulting in batteries that may combust upon failure. This flammability can be attributed to the configurational strain in cyclic organic electrolytes. Due to the lack of configurational strain in a flexible polymer chain, designing polymer electrolytes for use in lithium ion batteries may result in a safer battery due to their lower flammability in comparison to traditional liquid organic electrolytes. From the perspective of an electrolytic polymer, lowering the …

Development Of Entubulation Strategies For Treating Central Nervous System Injuries, Ivy Brosch

Williams Honors College, Honors Research Projects

According to the McKnight Brain Institute, at least 10,000 people annually in the USA suffer from a central nervous system (CNS) injury. These injuries can cause serve disabilities including paralysis. Due to the complexity of the spinal cord, it is common that potential CNS treatments are first applied to an optic nerve crush (ONC) model in rats. Two proposed treatments were employed; one where nerve growth factor (NGF) was immobilized to a chitosan substrate to stimulate axonal regeneration, and the other using pentadecafluorooctanoyl chloride modified methacrylamide chitosan (MAC(Ali15)F) hydrogel to enhance local oxygenation. The two different treatments were formed into …

Environmentally Friendly Alternates To Chemlok 233 Adhesive Cement, Madeline M. Busch

Williams Honors College, Honors Research Projects

The purpose of this project was to determine and qualify suitable, environmentally friendly replacement(s) for the current Chemlok 233 adhesive cement used by UTC Aerospace. Chemlok 233 was discontinued by the manufacturer based on the availability of a hazardous solvent (Trichloroethylene – TCE). The Chemlok 233 Control and four Experimental alternates with similar properties were lab tested for adhesion strength in various UTC proprietary cement specifications. The specifications modeled Chemlok’s uses in the construction of pneumatic de-icers. Chemlok 2332 was selected for use in Cement A, and Chemlok 402 was chosen for use in Cement B based on their highest …

Correlation Of Electrospun Polyvinylpyrrolidone Fiber Mat Thickness With Basis Weight, Fiber Diameter, Pore Size Distribution, And Air Permeability, Leah Mcpherson

Williams Honors College, Honors Research Projects

This project developed correlations between electrospun polyvinylpyrrolidone fiber mat thickness, basis weight, fiber diameter, pore size, and air permeability. The hypotheses were thinner fibers produce thicker mats, pore size decreases with fiber diameter, pore size and permeability decrease as basis weight increases. Project results could be used for modeling or quality control purposes.

Fiber diameter distributions were analyzed using a Scanning Electron Microscope and FibraQuant 1.3 software. Four conditions were chosen for further study: 0.284 ± 0.104 µm, 0.379 ± 0.128 µm, 0.520 ± 0.138 µm, and 0.733 ± 0.177 µm. Lower PVP concentrations produced thinner fibers.

Sample thickness (nm) …

Vanadium Redox Flow Batteries: Design And Experimentation, Matthew George

Williams Honors College, Honors Research Projects

Vanadium flow batteries (VFB) are a type of battery that has potential as a grid-scale energy storage solution. An original design for a lab-scale VFB is presented herein, along with a procedure for electrolyte preparation from V₂O₅ using oxalic acid. The flow cell is constructed from Delrin, Teflon, Kynar, Santoprene, Nafion, graphite plate, and porous carbon. Two diaphragm pumps along with polyethylene, PVC, and Santoprene tubing are used. The active area is 58 cm². The battery was charged using a DC power supply at a constant current of 4 A with corresponding initial voltage of …

Analyzing The Spectral Energy Cascade In Turbulent Channel Flow, João Rodrigo Andrade, Ramon Silva Martins, Gilmar Mompean, Laurent Thais, Thomas B. Gatski

CCPO Publications

An analysis of the spectral turbulent kinetic energy budget in a fully developed turbulent plane channel flow is performed. Direct numerical simulation data are evaluated at friction Reynolds numbers Re_τ of 180 and 1000. The analysis is focused on the influence of the Reynolds number on the spectral cascade of energy and the corresponding energy cascade in physical space in the presence of inhomogeneity and anisotropy. The turbulent kinetic energy distribution is compared for both Reynolds numbers, and the relevant characteristics of the energy transfer process in a wall-bounded turbulent flow are described. Differences in energy cascade are noted …

A Preliminary Evaluation Of The Ability Of Keratotic Tissue To Act As A Prognostic Indicator Of Hip Fracture Risk, J. Renwick Beattie, Diane Feskanich, M. Clare Caraher, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Studies have shown that Raman spectroscopic analysis of fingernail clippings can help differentiate between post-menopausal women who have and who have not suffered a fracture. However, all studies to date have been retrospective in nature, comparing the proteins in nails sourced from women, post-fracture. The objective of this study was to investigate the potential of a prospective test for hip fracture based on spectroscopic analysis of nail tissue. Archived toenail samples from post-menopausal women aged 50 to 63 years in the Nurses' Health Study were obtained and analysed by Raman spectroscopy. Nails were matched case-controls sourced from 161 women; 82 …

Characterization Of Pyrolysis Products From Fast Pyrolysis Of Live And Dead Vegetation Native To The Southern United States, Mohammad-Saeed Safdari, Mahmood Rahmati, Elham Amini, Joel E. Howarth, Jansen P. Berryhill, Mark Dietenberger, David R. Weise, Thomas H. Fletcher

Faculty Publications

Prescribed burning (controlled burning) is used to decrease accumulation of combustible materials and reduce impact of uncontrolled wildland fires. Prescribed fires are often used to burn undergrowth in Southern forests of the United States. In order to improve prescribed fire application, accomplish desired fire effects, and limit potential runaway fires, an improved understanding of the fundamental processes related to combustion of heterogeneous fuel beds of live and dead fuels is needed. The initial processes of combustion involve pyrolysis and ignition. During this research, fast pyrolysis of 14 live and dead (biomass) plant species which are native to the Southern United …

Fire Behavior In Chaparral–Evaluating Flame Models With Laboratory Data, David R. Weise, Thomas H. Fletcher, Wesley Cole, Shankar Mahalingam, Xiangyang Zhou, Lulu Sun, Jing Li

Faculty Publications

Flame and mass loss data for chaparral, a mixture of shrub plants from the Mediterranean climate zone of southwestern North America, from five previously reported experiments were used to evaluate several published models relating flame characteristics to mass loss and heat release rates. These data are unique with fuel moisture content ranging from 0.36 to 0.94 (dry basis); the study used mass loss rates which included water loss. Fit of the data to Froude number correlations developed by Albini, Byram, Nelson and Thomas and heat release rate—flame length correlations by Heskestad, Zukoski, and Yuan/Cox for axisymmetric and line fires were …