Chemical Engineering Commons^™

The Design Of Nanostructures From The Blending Of Flowing Agents Influencing Critical Properties Of A Pharmaceutical Formulation, Casey F. Kick

Masters Theses

In the pharmaceutical manufacturing process, it is well known that flowing agents such as MgSt and Cab-O-Sil widely affect critical flow properties that influence the finished product performance of oral dosage tablets. Though the effects of flowing agents are beneficial to some extent, the sensitivity of the pharmaceutical formulation to process shearing of flowing agents during blending can be catastrophic which often results in product and batch failures. Hence it is essential to study the concentration of flowing agents and chemical nature of active pharmaceutical ingredients (API) with respect to applied process shear on formulations. Previous studies have shown that …

Development And Verification Of A Method To Determine The Long Term Load Carrying Performance Of A Double Sided Pressure Sensitive Adhesive Tape, Rahal Rasheed

Masters Theses

Acrylic foam pressure sensitive adhesive (PSA) tapes are used in various applications as an alternative of mechanical fasteners, especially in areas like structural bonding which requires demanding bond strength and durability.

This research focuses on comparing design values of acrylic foam PSA using static shear test method and dynamic shear test method in accordance of J0MP0164 standard specification. Static shear test has lots of disadvantages; but on the other hand it is the test that mimics the real life usage of a tape in a real life application. Dynamic shear test is a faster way of testing and gives a …

Silver Nanoparticle Coated Bioactive Glasses - Composites With Dex/Cmc Hydrogels: Characterization, Solubility, And In Vitro Biological Studies, Anthony W. Wren, Pegah Hassanzadeh, Lana M. Placek, Timothy J. Keenan, Aisling Coughlan, Lydia R. Boutelle, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Silver (Ag) coated bioactive glass particles (Ag-BG) were formulated and compared to uncoated controls (BG) in relation to glass characterization, solubility and microbiology. X-ray diffraction (XRD) confirmed a crystalline AgNP surface coating while ion release studies determined low Ag release (/L). Cell culture studies presented increased cell viability (127 and 102%) with lower liquid extract (50 and 100 ml/ml) concentrations. Antibacterial testing of Ag-BG in E. coli, S. epidermidis and S. aureus significantly reduced bacterial cell viability by 60-90%. Composites of Ag-BG/CMC-Dex Hydrogels were formulated and characterized. Agar diffusion testing was conducted where Ag-BG/hydrogel composites produced the largest inhibition zones …

System And Process For Upgrading Hydrocarbons, Dennis N. Bingham, Kerry M. Klingler, Joseph D. Smith, Terry D. Turner, Bruce M. Wilding

Chemical and Biochemical Engineering Faculty Research & Creative Works

In one embodiment, a system for upgrading a hydrocarbon material may include a black wax upgrade subsystem and a molten salt gasification (MSG) subsystem. The black wax upgrade subsystem and the MSG subsystem may be located within a common pressure boundary, such as within a pressure vessel. Gaseous materials produced by the MSG subsystem may be used in the process carried out within the black wax upgrade subsystem. For example, hydrogen may pass through a gaseous transfer interface to interact with black wax feed material to hydrogenate such material during a cracking process. In one embodiment, the gaseous transfer interface …

Impact Of Calendering And Silver Addition To Carbon Nanotube-Based Electrodes Used In Printed Multi-Layer Capacitors, Ramea Awni Al-Mubarak

Masters Theses

As the demand for global energy increases, the need for development of alternative clean and sustainable energy technology increases. Creating advanced energy devices with a large storage capacity plays a significant role in this development. This research focused on investigating the performance of capacitor devices used as energy storage cells by optimizing and determining the impact of silver percentage and structure (nano-wires or silver flake) added to CNT ink on the conductivity of printed layers, and studying the influence of calendering the multi-layer capacitor electrodes. Multi-layer capacitors were fabricated by screen printing three alternative layers of conductive and dielectric inks …

Low Melting Glass Frit As An Adhesion And Resistivity Promotor To Silver Nanoparticle Ink Photonically Sintered On Indium Tin Oxide Coated Glass, Jason J. Kleiner

Masters Theses

The objective of this study was the fabrication of a printed circuit resulting from the photonic drying/sintering of conductive circuits, printed using silver nano ink layered on a film of low melting glass frit onto indium tin oxide (ITO) coated glass substrate through the flexographic printing method. The fabrication process flow included material preparation, printing, and photonic drying/sintering in that order.

Investigation of the breakthrough photonic drying/sintering method was studied by varying sintering parameters, specifically the amount of heat energy applied to each specimen, and the speed at which it was applied. Additionally, the adhesion promoting properties of a never …

Bioactive Glass Reinforced Elastomer Composites For Skeletal Regeneration: A Review, Ehsan Zeimaran, Sara Pourshahrestani, Ivan Djordjevic, Belinda Pingguan-Murphy, Nahrizul Adib Kadri, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Biodegradable elastomers have clinical applicability due to their biocompatibility, tunable degradation and elasticity. The addition of bioactive glasses to these elastomers can impart mechanical properties sufficient for hard tissue replacement. Hence, a composite with a biodegradable polymer matrix and a bio glass filler can offer a method of augmenting existing tissue. This article reviews the applications of such composites for skeletal augmentation.

Hydrocarbon-Based Fuel Cell Membranes: Sulfonated Crosslinked Poly(1,3-Cyclohexadiene) Membranes For High Temperature Polymer Electrolyte Fuel Cells, Suxiang Deng, Mohammad K. Hassan, Kenneth A. Mauritz, Jimmy W. Mays

Faculty Publications

High temperature fuel cell membranes based on poly(1,3-cyclohexadiene) were prepared by a Polymerization-Crosslinking-Sulfonation (PCS) approach, and a broad range of membrane compositions were achieved using various sulfonating reagents and reaction conditions. Membranes were characterized for their proton conductivity and thermal degradation behavior. Some of the membranes showed up to a 68% increase in proton conductivity as compared to Nafion under the same conditions (100% relative humidity and 120 °C). Thermogravimetric analysis revealed that these membranes are thermally stable up to 200 °C. High proton conductivity and thermal stability, combined with much lower cost as compared to Nafion®, make these materials …

Electrode Side Reactions, Capacity Loss And Mechanical Degradation In Lithium-Ion Batteries, Jiagang Xu, Rutooj D. Deshpande, Jie Pan, Yang-Tse Cheng, Vincent S. Battaglia

Chemical and Materials Engineering Faculty Publications

For advancing lithium-ion battery (LIB) technologies, a detailed understanding of battery degradation mechanisms is important. In this article, experimental observations are provided to elucidate the relation between side reactions, mechanical degradation, and capacity loss in LIBs. Graphite/Li(Ni_1/3Mn_1/3Co_1/3)O₂ cells of two very different initial anode/cathode capacity ratios (R, both R > 1) are assembled to investigate the electrochemical behavior. The initial charge capacity of the cathode is observed to be affected by the anode loading, indicating that the electrolyte reactions on the anode affect the electrolyte reactions on the cathode. Additionally, the rate of “marching” …

Economic And Sustainability Aspects Of Chemical Process Industries By Thermodynamics Analysis, Mahdi H. Alhajji

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

Economics and sustainability improvements of some chemical processes are assessed after the retrofits suggested by thermodynamic analysis and energy analyzer. The main objective is to explore the scope of reducing the energy consumption and CO₂ emissions for a more sustainable operation in chemical process industries. Thermodynamic analysis is carried out by applying the thermal analysis capability of ‘Column Targeting Tool’ to address the ‘energy intensity,’ and/or the ‘Energy Analyzer’ to design and improve the performance of the heat exchanger network system for process heat integration. CTT is based on the ‘Practical Near-Minimum Thermodynamic Condition’ representing a close to practical …

A Quantitative Perspective On Surface Marker Selection For The Isolation Of Functional Tumor Cells, Calvin F. Cahall, Jacob L. Lilly, Edward A. Hirschowitz, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

Much effort has gone into developing fluid biopsies of patient peripheral blood for the monitoring of metastatic cancers. One common approach is to isolate and analyze tumor cells in the peripheral blood. Widespread clinical implementation of this approach has been hindered by the current choice of targeting epithelial markers known to be highly variable in primary tumor sites. Here, we review current antigen-based tumor cell isolation strategies and offer biological context for commonly studied cancer surface markers. Expression levels of the most common markers are quantitated for three breast cancer and two non-small cell lung cancer (NSCLC) lineage models. These …

A Mathematical Model Of A Control Systems Hypothesis Of N-Methyl-D-Aspartate-Receptor-Mediated Ethanol Dependence And Withdrawal Dynamics, Carlos Gutierrez

Theses and Dissertations

The biochemical effects of ethanol on the human brain are manifested through many neurological pathways. Chronic exposure to the depressant has been shown to result in physical dependence. Subsequent cessation results in withdrawal symptoms such as seizures and both short- and long-term changes in neurological activity. One of the primary conduits implicated in the pathways of ethanol dependence and withdrawal is the detection of glutamate via N-methyl-D-aspartate (NMDA) receptors (NMDARs). Ethanol molecules inhibit these receptors, and consequent NMDA-induced glutamatergic changes can result in dependence on ethanol in order to sustain normal brain function. This study considers the relocation control of …

Matrix Compliance And The Regulation Of Cytokinesis, Savitha Sambandamoorthy, Shomita Mathew-Steiner, Scott Varney, Jonathan M. Zuidema, Ryan J. Gilbert, Livingston De Van Water, Susan E. Laflamme

Chemical and Biochemical Engineering Faculty Research & Creative Works

Integrin-mediated cell adhesion to the ECM regulates many physiological processes in part by controlling cell proliferation. It is well established that many normal cells require integrin-mediated adhesion to enter S phase of the cell cycle. Recent evidence indicates that integrins also regulate cytokinesis. Mechanical properties of the ECM can dictate entry into S phase; however, it is not known whether they also can affect the successful completion of cell division. To address this issue, we modulated substrate compliance using fibronectin-coated acrylamide-based hydrogels. Soft and hard substrates were generated with approximate elastic moduli of 1600 and 34,000 Pascals (Pa) respectively. Our …

The Role Of Environmental Dynamics In The Emergence Of Autocatalytic Networks, Joe Fusion

Dissertations and Theses

For life to arise from non-life, a metabolism must emerge and maintain itself, distinct from its environment. One line of research seeking to understand this emergence has focused on models of autocatalytic reaction networks (ARNs) and the conditions that allow them to approximate metabolic behavior. These models have identified reaction parameters from which a proto-metabolism might emerge given an adequate matter-energy flow through the system. This dissertation extends that research by answering the question: can dynamically structured interactions with the environment promote the emergence of ARNs? This question was inspired by theories that place the origin of life in contexts …

Optimum 3d Matrix Stiffness For Maintenance Of Cancer Stem Cells Is Dependent On Tissue Origin Of Cancer Cells, Esmaiel Jabbari, Samaneh K. Sarvestani, Leily Daneshian, Seyedsina Moeinzadeh

Faculty Publications

Introduction

The growth and expression of cancer stem cells (CSCs) depend on many factors in the tumor microenvironment. The objective of this work was to investigate the effect of cancer cells’ tissue origin on the optimum matrix stiffness for CSC growth and marker expression in a model polyethylene glycol diacrylate (PEGDA) hydrogel without the interference of other factors in the microenvironment.

Methods

Human MCF7 and MDA-MB-231 breast carcinoma, HCT116 colorectal and AGS gastric carcinoma, and U2OS osteosarcoma cells were used. The cells were encapsulated in PEGDA gels with compressive moduli in the 2-70 kPa range and optimized cell seeding density …

Secondary Organic Aerosol Formation From The Β-Pinene+No3 System: Effect Of Humidity And Peroxy Radical Fate, C. M. Boyd, J. Sanchez, L. Xu, Alexis J. Eugene, T. Nah, W. Y. Tuet, Marcelo I. Guzman, N. L. Ng

Chemistry Faculty Publications

The formation of secondary organic aerosol (SOA) from the oxidation of β-pinene via nitrate radicals is investigated in the Georgia Tech Environmental Chamber (GTEC) facility. Aerosol yields are determined for experiments performed under both dry (relative humidity (RH) < 2 %) and humid (RH = 50 % and RH = 70 %) conditions. To probe the effects of peroxy radical (RO₂) fate on aerosol formation, "RO₂ + NO₃ dominant" and "RO₂ + HO₂ dominant" experiments are performed. Gas-phase organic nitrate species (with molecular weights of 215, 229, 231, and 245 amu, which likely correspond to molecular formulas of C₁₀H₁₇NO₄, C₁₀H₁₅NO₅, C₁₀H₁₇NO …

Platinum-Bismuth Bimetallic Catalysts: Synthesis, Characterization And Applications, Jose A. Saucedo Jr, Yang Xiao, Arvind Varma

The Summer Undergraduate Research Fellowship (SURF) Symposium

Bimetallic catalysts have been explored and shown to exhibit unique characteristics which are not present in monometallic catalysts. Platinum is well known as an effective catalyst for oxidation and reduction reactions, and it can be made more effective when bismuth is introduced as a promotor. Thus, the effectiveness of the Pt-Bi catalyst was demonstrated in prior work. What is not clear, however, is the mechanism behind the catalyst function; why addition of bismuth to platinum decreases deactivation and increases selectivity, and how effective would the Pt-Bi catalyst be in deoxygenation reactions? In this work, the effectiveness of different variations of …

Gold Nanoparticle Enhancements In Electroporation Mediated Dna And Rna Therapeutics, Shuyan Huang

Doctoral Dissertations

Nonviral gene delivery methods have been explored as the replacement of viral systems for their low toxicity and immunogenicity. However, they have yet to reach levels competitive to their viral counterparts. Electroporation figured prominently as an effective nonviral gene delivery approach for its balance on the transfection efficiency and cell viability, no restrictions of probe or cell type, and operation simplicity. The commercial electroporation systems have been widely adopted in the past two decades but still carry drawbacks associated with the high applied electric voltage, unsatisfied delivery efficiency, and/or low cell viability. What we did was to improve electroporation performance …

Swelling-Etching Characterization Of Copper (I) Oxide - Pdms For The Development Of Micro/Nano - Particles Composite Mems Corrosion Sensor, Abdoul Kader Maiga

Graduate Theses and Dissertations

The primary objective for this thesis is to contribute to the understanding of the oxide removal process for a corrosion sensing device. The goal for designing such a device is for monitoring corrosion on metallic structures. The sensing material (6.35mm x 1mm discs) of the device is composed of copper (I) oxide particles mixed in some polydimethylsiloxane (PDMS). The PDMS, “housing,” is meant for controlling the oxidation rate through the sensing material. A solvent was used to facilitate the etchant diffusion through the PDMS matrix. Toluene and acetic acid were the ideal solvent and etchant, respectively, for carrying out the …

Diamond Mems Biosensors: Development And Applications, Wenli Zhang

Doctoral Dissertations

This research focuses on the development a dielectrophoresis-enhanced microfluidic impedance biosensor (DEP-e-MIB) to enable fast response, real-time, label-free, and highly sensitive sensor for bacterial detection in clinical sample. The proposed design consists of application of dielectrophoresis (DEP) across a microfluidic channel to one of the impedance spectroscopy electrodes in order to improve the existent bacterial detection limits with impedance spectroscopy. In order to realize such a design, choice of electrode material with a wide electrochemical potential window for water is very important. Conventional electrode material, such as gold, are typically insulated for the application of DEP, and they fail when …