Engineering Commons^™

Engineered Excipients Via Dry Particle Coating, Liang Chen

Dissertations

Excipients with good flowability, bulk density as well as compaction properties are desired for use in tableting since they play important roles in formulation development and processing, including, handling, mixing, feeding and compaction. However, it is often difficult to manufacture excipients that simultaneously possess all three desirable properties, particularly if their size is fine. In addition, it is desirable that the excipients promote direct compression of poorly compactable fine cohesive drug powders at sufficiently high drug loading, and not just achieve the desired high functional properties in placebo formulations. This dissertation aims to developed engineered excipients towards this unmet industry …

Enzyme-Assisted Development Of Hydrogels As Medical Materials With Injectable, Biodegradable And Biocompatible Properties, Yung-Hao Tsou

Dissertations

Hydrogels were first discovered in the year 1960 by Wichterle and Lim [1], and in the following decades, they have been widely studied because of their unique characteristics including their hydrophilic nature, biocompatibility, and capacity to mimic the extracellular matrix (ECM). Hydrogels based on natural or synthetic polymers have continued to be of interest for tissue engineering and drug delivery due to their ability to encapsulate living cells and control the release rate of drugs or other bioactive molecules such as pharmaceutical proteins.

In the first part of this dissertation, dopant-free photoluminescent hydrogels formed in situ by crosslinking of biocompatible …

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman

Theses

Njs, the minimum agitation speed needed to just suspend all the solid particles in a solid-liquid mixture stirred in an agitated vessel, is a critical parameter to properly operate industrial tanks in a large number of industrial operations. As a result, a significant literature on Njs is available. The oldest and the most common method to measure Njs experimentally is that of Zwietering’s (Chem. Eng. Sci., 1958, 8, 244-253), where Njs can be visually obtained by determining when the solids stay at the bottom of the tank for no more than 1-2 seconds before being swept away. Although this has …

Glass Transition Temperature Of Particles For Drug Delivery, Yiqing Yang

Theses

Drug delivery plays an important role in targeted therapies and nanoparticles which can be used as drug carriers and it’s a frequently researched topic. Poly(lactic-co-glycolic acid) (PLGA), a highly biocompatible polymer, has been used as a drug delivery vehicle in many studies. One of the challenges facing drug delivery particles is the problem of burst release which is when a large amount of the drug is suddenly released from the particle once it is placed in the body. This is generally undesirable as usually a slow and controlled release is preferred. The glass transition temperature has an effect on drug …

Highly Effective Geni Alloy Contact Diffusion Barrier For Bisbte Long-Term Thermal Exposure, Erdong Song, Brian S. Swartzentruber, Chowdary R. Koripella, Julio A. Martinez

Publications and Research

A GeNi alloy diffusion barrier for contacts on bismuth antimony telluride is proposed. Multiple gold contact diffusion barriers were tested at different thermal aging conditions in air and reducing atmospheres. Among all diffusion barriers, the GeNi alloy barrier shows the best performance for bulk samples with no substantial degradation of the contact resistance, no contact color change, and no change of thermoelectric properties. We observed DAu−GeNi = (9.8 ± 2.7) × 10−20 m2/s within the GeNi alloy barrier, which is 4 times smaller than DAu−BiSbTe. The presence of the initial Ge layer also proves to be effective in reducing nickel …

Challenges For Natural Hydrogels In Tissue Engineering, Esmaiel Jabbari

Faculty Publications

Protein-based biopolymers derived from natural tissues possess a hierarchical structure in their native state. Strongly solvating, reducing and stabilizing agents, as well as heat, pressure, and enzymes are used to isolate protein-based biopolymers from their natural tissue, solubilize them in aqueous solution and convert them into injectable or preformed hydrogels for applications in tissue engineering and regenerative medicine. This review aims to highlight the need to investigate the nano-/micro-structure of hydrogels derived from the extracellular matrix proteins of natural tissues. Future work should focus on identifying the nature of secondary, tertiary, and higher order structure formation in protein-based hydrogels derived …

Challenges For Natural Hydrogels In Tissue Engineering, Esmaiel Jabbari

Faculty Publications

Protein-based biopolymers derived from natural tissues possess a hierarchical structure in their native state. Strongly solvating, reducing and stabilizing agents, as well as heat, pressure, and enzymes are used to isolate protein-based biopolymers from their natural tissue, solubilize them in aqueous solution and convert them into injectable or preformed hydrogels for applications in tissue engineering and regenerative medicine. This review aims to highlight the need to investigate the nano-/micro-structure of hydrogels derived from the extracellular matrix proteins of natural tissues. Future work should focus on identifying the nature of secondary, tertiary, and higher order structure formation in protein-based hydrogels derived …

Hypermongone C Accelerates Wound Healing Through The Modulation Of Inflammatory Factors And Promotion Of Fibroblast Migration, Sara E. Moghadam, Moridi Mahdi Farimani, Sara Soroury, Samad N. Ebrahimi, Ehsan Jabbarzadeh

Faculty Publications

The physiology of wound healing is dependent on the crosstalk between inflammatory mediators and cellular components of skin regeneration including fibroblasts and endothelial cells. Therefore, strategies to promote healing must regulate this crosstalk to achieve maximum efficacy. In light of the remarkable potential of natural compounds to target multiple signaling mechanisms, this study aims to demonstrate the potential of hypermongone C, a polycyclic polyprenylated acylphloroglucinol (PPAP), to accelerate wound closure by concurrently enhancing fibroblast proliferation and migration, promoting angiogenesis, and suppressing pro-inflammatory cytokines. This compound belongs to a family of plants (Hypericum) that traditionally have been used to treat injuries. …

Non-Canonical Amino Acid Labeling In Proteomics And Biotechnology, Aya M. Saleh, Kristen M. Wilding, Sarah Calve, Bradley Charles Bundy, Tamara L. Kinzer-Ursem

Faculty Publications

Metabolic labeling of proteins with non-canonical amino acids (ncAAs) provides unique bioorthogonal chemical groups during de novo synthesis by taking advantage of both endogenous and heterologous protein synthesis machineries. Labeled proteins can then be selectively conjugated to fluorophores, affinity reagents, peptides, polymers, nanoparticles or surfaces for a wide variety of downstream applications in proteomics and biotechnology. In this review, we focus on techniques in which proteins are residue- and site-specifically labeled with ncAAs containing bioorthogonal handles. These ncAA-labeled proteins are: readily enriched from cells and tissues for identification via mass spectrometry-based proteomic analysis; selectively purified for downstream biotechnology applications; or …

The Effect Of Fabric Architecture On The Processing And Properties Of Composites Made By Vacuum Assisted Resin Transfer Molding, Francois Ntakobatagize, Oscar Ntakontagize, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

The goal of this research project was to evaluate and compare the effect of fabric architecture on the processing and properties of composites made by Vacuum Assisted Resin Transfer Molding (VARTM). The fabric architectures investigated included plain weave, satin weave, and warp-knit unidirectional. The fiber types included E-glass and standard modulus carbon fiber. Flat panels were fabricated with a lab scale VARTM process using an epoxy resin system. Fabric plies were cut to 45 cm x 30 cm (18 in. x 12 in.), and the number of plies used depended on the fiber areal weight of each fabric to produce …

Fabrication Of Enhanced Carbon Based Biocompatible And Biodegradable Microelectronic Materials Derived From Lignocellulosic Biomass, Harrison Thomas Hawkins

Theses and Dissertations

The development of materials capable of harmlessly being broken down and removed from the body is a crucial step towards the development of short-term application electronic biomedical implants. Once developed, these implants, known as bioresorbable electronics, will open a wide array of temporary applications in the field of biomedical implantable devices. Necessary to the operation of bioresorbable electronics within the body is a power source that is similarly biocompatible and biodegradable. To this end, enhanced carbon-based materials and a bio-ionic liquid were developed for the fabrication of a preliminary implantable and bioresorbable battery and tested for functional properties. Electrodes were …

Modeling Of Vapor Sorption In Nanoparticle Chemiresistors, Alexandra Oliveira

Honors Scholar Theses

Chemical vapor sensors possess a number of uses in a variety of fields, from environmental and health monitoring to food safety and national security concerns, such as the detection of improvised explosive devices. Many sensors currently in the market have the ability to detect the presence of a select few compounds and measure the concentration at which the species is present. However, these types of sensors require that the vapor to be investigated is known beforehand; they cannot be used for identification except on a case by case basis. In response to this issue, one branch of vapor sensor research …

Symmetry And Dopant Diffusion In Inverted Nanopyramid Arrays For Thin Crystalline Silicon Solar Cells, Seok Jun Han

Chemical and Biological Engineering ETDs

In this dissertation, we enhance the efficiency of thin flexible monocrystalline silicon solar cells by breaking symmetry in light trapping nanostructures and improving homogeneity in dopant concentration profile. These thin cells are potentially less expensive than conventional thick silicon cells by using less silicon material and making the cells more convenient to be handled when supported on polymer films. Moreover, these cells are widely applicable due to their flexibility and lightweight. However, for high efficiencies, these cells require effective light trapping and charge collection. We achieve these in cells based on 14-mm-thick free-standing silicon films with light-trapping arrays of nanopyramidal …

Exploring Methodologies To Improve Lignin Utilization In Biorefineries, James Meyer

McKelvey School of Engineering Graduate Student Theses & Dissertations

The increasing world population, coupled with an improving quality of life, has driven a rapidly increasing demand for fuels, chemicals, and materials. Fossil carbon feedstocks, such as petroleum, are currently being consumed to meet these demands. The utilization of these feedstocks has negative impacts on human and environmental health, which are undoubtedly intensifying as a result of the increased reliance required to meet these demands. As an alternative way to meet these demands, biorefineries generate a wide range of fuels, chemicals, and materials from biomass, a renewable and sustainable resource. Current second-generation biorefineries use a plant-based feedstock, lignocellulosic biomass, comprised …

Fluid Transport In Porous Media For Engineering Applications, Eric M. Benner

Chemical and Biological Engineering ETDs

This doctoral dissertation presents three topics in modeling fluid transport through porous media used in engineering applications. The results provide insights into the design of fuel cell components, catalyst and drug delivery particles, and aluminum- based materials. Analytical and computational methods are utilized for the modeling of the systems of interest. Theoretical analysis of capillary-driven transport in porous media show that both geometric and evaporation effects significantly change the time dependent behavior of liquid imbibition and give a steady state flux into the medium. The evaporation–capillary number is significant in determining the time-dependent behavior of capillary flows in porous media. …

Cellular Modification And Artificial Cell Construction, Jimin Guo

Chemical and Biological Engineering ETDs

With all its complexities and different biofunctionalities, a cell is the basic structural and functional unit of all living organisms with the exception of viruses. In this dissertation, I demonstrated gain of function strategies of modifying mammalian cells using silicification and modular nanoparticle (NP) exoskeletons. In addition, I used a modular design concept to build a multifunctional artificial RBC system which can mimic the unique characteristics (e.g. shape, flexibility, the ability to carry oxygen, and long circulation times) of the native RBCs. Together, these cell modification or artificial cell construction strategies are expected to generate new mammalian cell-like structures with …

A Model-Based Framework For The Smart Manufacturing Of Polymers, Santiago D. Salas Ortiz

LSU Doctoral Dissertations

It is hard to point a daily activity in which polymeric materials or plastics are not involved. The synthesis of polymers occurs by reacting small molecules together to form, under certain conditions, long molecules. In polymer synthesis, it is mandatory to assure uniformity between batches, high-quality of end-products, efficiency, minimum environmental impact, and safety. It remains as a major challenge the establishment of operational conditions capable of achieving all objectives together. In this dissertation, different model-centric strategies are combined, assessed, and tested for two polymerization systems.

The first system is the synthesis of polyacrylamide in aqueous solution using potassium persulfate …

Equivalent Annual Operating Cost Of Reactors In A Discrete Optimized Styrene Process, S Arizona Morgan-Harris

Honors Theses

Beginning in the fall semester, I was a member of a team that simulated and optimized a styrene production process in Microsoft Excel. After the base case was simulated, parametric and topological optimizations were completed. The optimizations had to be completed in a certain order that starts with the reactor section, then move to the separation section, heat recovery section, heating/cooling utilities section, and ends with the water and effluent treatment section. During this project, the first three sections were explored. Optimizing the base case was completed by making these changes to see how they increased the net present value …

“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications, Phillip Pickett

Dissertations

Amphiphilic copolymers have become increasingly important for environmental and biological applications due to their behavioral characteristics in aqueous solution. For example, structurally-tailored statistical amphiphilic copolymers or “polysoaps” can self-assemble into micelles or other architectures in water at various concentrations. Polysoaps may be differentiated from small molecule surfactant micelles in their capability to self-assemble into unimolecular associates (unimolecular micelles) with no dependence on concentration. Such micelles offer enormous potential for dispersion of hydrophobic species in water at high dilution. Importantly, each polymer chain forms its own micelle and upon dilution, these micelles remain intact and capable of dispersing hydrocarbon material in …

Chemical And Physical Modification Of Thiol-Ene And Epoxy-Amine Networks For Advanced Control Of Gas Transport And Flame Retardant Behavior, Vivek Vasagar

Dissertations

Crosslinked polymers are widely used due to its several advantages not limited to high mechanical strength combined with the easy processability. Despite of its popular usage, the fundamental understanding of polymer structure affecting the desired properties is still lacking. This PhD thesis is in two parts, the first part is devoted to the design and developing a basic understanding of structure and chemical composition dependencies of gas transport, whereas in the second part a fundamental relationship between structure to the fire-retardant properties is established.

Membrane based gas separation technique has attracted interest of selective removal of carbon dioxide gas from …

Bioinspired Glycopolymers: Models To Investigate The Effect Of Saccharide Structure And Concentration On Amyloid Beta Aggregation, Pradipta Kumar Das

Dissertations

Aggregation and subsequent deposition of amyloid-β (Aβ) peptide on neuronal cell membranes have been implicated as a cause of Alzheimer’s disease. Gangliosides in their clustered form seed and promote the Aβ aggregation process. However, the effects of the structure and the concentration of ganglioside saccharides on Aβ aggregation are not well understood. We investigated how the specific structure of saccharides (β-D-galactose and β-D-glucose) affect the aggregation pathways, kinetics, and the aggregated structures of Aβ via in vitro experiments. The effects of the local concentration of saccharides on the Aβ aggregation were also investigated.

To mimic the multivalent effect of the …

How Moisture Content Levels And Packing Density In Soil Affect Crude Oil Spreads, Shaylin N. Williams

Venture: The University of Mississippi Undergraduate Research Journal

Crude oil spills are one of the most destructive disasters that can occur, and they are extremely difficult to recover from. Many studies focus on what can be done to clean these crude oil spills, but more research should be focused on means of prevention. Currently, very little is known about how the moisture content levels and the packing efficiency of soil can affect an oil spill. These two factors alone can offer a variety of information to environmental agencies, manufacturers, and refineries. Through utilization of a chemical engineering lab, a recording mechanism, and ImagePro software, data was collected and …

Nanowire Based Adsorbents/Catalysts For Co2 Capture And Utilization., Apolo Nambo

Electronic Theses and Dissertations

Even today, the major energy source is fossil fuels, which release CO₂, a greenhouse gas that contributes to global warming. CO₂ capture, storage (CCS) and/or utilization (CCU) technologies are two routes to mitigate this problem. Sorbents are being investigated in either temperature swing or pressure swing absorption approaches for carbon capture from flue gases. Solid sorbent based technology is a promising one but suffers from slow kinetics, low capacity and need for high temperatures. Thus, new sorbent materials that can have good CO₂ sorption capacity, recyclability are sought. Similarly, one of the utilization approaches for CO …

Plasma-Assisted Liquid Phase Epitaxy Of Gallium Nitride Using Molten Gallium., Daniel Felipe Jaramillo-Cabanzo

Electronic Theses and Dissertations

Next generation semiconductor materials such as Gallium Nitride (GaN) and Silicon Carbide (SiC) are rapidly replacing Silicon (Si) for high power and high frequency applications due to Si’s inherent limitations. Despite the advantages of GaN over SiC, adoption of GaN has been hindered due to the lack of a cost-effective bulk production technique. Thus, the inability to precure native substrates requires GaN-based architectures to be heteroepitaxially synthesized on non-native substrates, such as sapphire and even SiC. This research seeks to develop a cost effective and scalable method to produce low defect, bulk GaN encouraging the adoption of GaN based devices …

Plasma Oxidation Of Liquid Precursors For Complex Metal Oxides., Babajide Patrick Ajayi

Electronic Theses and Dissertations

Clean energy production and storage are two of the most significant challenges in the 21^st century currently limited by the discovery and development of new and advanced materials. Complex oxides and alloys made using earth-abundant elements will play a crucial role in technology development moving forward, however, current preparation techniques are limited by their inability to produce complex oxides and alloys with precise composition control at fast timescales. A concept was proposed to produce mixed metal oxides with composition control through the oxidation of liquid precursors via plasma oxidation. It was hypothesized that the oxidation process can be completed …

Investigation Of Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Fe3o4 As Efficient Recyclable Magnetic Catalysts For Suzuki-Miyaura Cross-Coupling, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this research, a facile and reproducible approach was implemented for the synthesis of palladium nanoparticles supported on Fe₃O₄ with remarkable activity as an ideal catalyst for Suzuki-Miyaura cross-coupling. Magnetite supported Pd nanoparticles reveal high activity in Suzuki-Miyaura coupling reactions since they could be recycled up to seven times with the same high catalytic activity. This adopted method of catalyst synthesis has many advantages, including reproducibility and the reliability of the adopted synthetic method. The produced catalyst has unique magnetic properties to facilitate catalyst recovery from the reaction mixture by using a strong magnet as an external …

Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Jennifer Gaines

Chemical Engineering Undergraduate Honors Theses

As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team …

Using Green Emitting Ph-Responsive Nanogels To Report Environmental Changes Within Hydrogels: A Nanoprobe For Versatile Sensing, Mingning Zhu, Dongdong Lu, Shanglin Wu, Qing Lian, Wenkai Wang, L. Andrew Lyon, Weiguang Wang, Paulo Bártolo, Brian R. Saunders

Engineering Faculty Articles and Research

Remotely reporting the local environment within hydrogels using inexpensive laboratory techniques has excellent potential to improve our understanding of the nanometer-scale changes that cause macroscopic swelling or deswelling. Whilst photoluminescence (PL) spectroscopy is a popular method for such studies this approach commonly requires bespoke and time-consuming synthesis to attach fluorophores which may leave toxic residues. A promising and more versatile alternative is to use a pre-formed nanogel probe that contains a donor/acceptor pair and then “dope” that into the gel during gel assembly. Here, we introduce green-emitting methacrylic acid-based nanogel probe particles and use them to report the local environment …

Design And Cost Analysis Of Acrylic Acid Plant, Adam Ferrier

Chemical Engineering Undergraduate Honors Theses

The purpose of this project was to model and design a plant to produce 75,000 tons per year of acrylic acid. Using the design in section B.9 of Richard Turton’s Analysis, Synthesis, and Design of Chemical Processes as a starting point, a plant was designed based around the partial oxidation of propylene to acrylic acid. The final plant design produces about 86,000 tons per year of acrylic acid. Using an interest rate of 10%, the plant has a discounted cash flow rate of return of 32% over 2 years of startup and 10 years of operation. Attached is an executive …

Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper presents a systematic method to analyse the stability of systems with single delay in which the coefficient polynomials of the characteristic equation depend on the delay. Such systems often arise in, for example, life science and engineering systems. A method to analyze such systems was presented by Beretta and Kuang in a 2002 paper, but with some very restrictive assumptions. This work extends their results to the general case with the exception of some degenerate cases. It is found that a much richer behavior is possible when the restrictive assumptions are removed. The interval of interest for the …