Engineering Commons^™

Antimicrobial Activity And Photostability Of Cationic Conjugated Polyelectrolytes, Mohammed Ismael Khalil

Chemical and Biological Engineering ETDs

Antimicrobial resistance is a growing global health concern, driving the need for novel

therapeutic strategies. This study explores the antimicrobial efficacy of conjugated

polyelectrolytes (CPEs) and oligo-phenylene ethynylenes (OPEs) in bacterial and viral

inactivation. Quantitative analysis revealed that light-activated CPEs and OPEs

effectively reduced bacterial viability within minutes, with significant log reductions

observed under both light and dark conditions. Additionally, the antiviral potential of a

cationic conjugated oligomer was investigated, demonstrating rapid and near-complete

inactivation of SARS-CoV-2 under visible light, both in solution and on filter materials.

Further analysis of their photophysical properties revealed that, even after

photobleaching, the compounds …

Cactus Infused Beads For Off-Flavor Mitigation In Aquaculture Systems, Rama Mahita Kambhampati

USF Tampa Graduate Theses and Dissertations

Aquaculture has become a vital component of global food production, now providing 50% of the world's fish supply. However, the industry encounters major challenges due to off-flavor compounds like Geosmin and 2-Methylisoborneol (MIB), which give fish an unpleasant earthy or musty smell. These compounds are detectable by humans at extremely low levels 0.7 parts per billion (ppb) for MIB and ten parts per trillion (ppt) for Geosmin—making them a persistent problem. Their presence not only reduces the sensory quality of aquaculture products but also results in significant economic losses, with U.S. catfish production incurring an additional $15–$23 million annually due …

Effect Of Specimen Size On The Tensile Properties Of Selective Laser Melted Ti-6ai-4v, Timothy L. Tan

Master's Theses

Metal additive manufacturing (MAM) is a burgeoning industry. It is capable of manufacturing metal components with fine, intricate features and enables localized microstructural control. Due to its fine resolution and compatibility with common engineering alloys, selective laser melting (SLM) is one particular MAM process popular in academia and industry. The biomedical and aerospace industries have shown exceptional interest in the capabilities of SLM with the alloy Ti-6Al-4V. Because SLM Ti-6Al-4V components are aimed for use in critical applications, it is necessary to understand how SLM processing characteristics affect final part performance. One characteristic of SLM Ti-6Al- 4V that requires further …

Collapse Of Pre-Covid-19 Differences In Performance In Online Vs. In-Person College Science Classes, And Continued Decline In Student Learning, Gregg R. Davidson, Hong Xiao, Kristin Davidson

Faculty and Student Publications

Abstract: Studies comparing student outcomes for online vs. in-person classes have reported mixed results, though with a majority finding that lower-performing students, on average, fare worse in online classes, attributed to the lack of built-in structure provided by in-person instruction. The online/in-person outcome disparity was normative for non-major geology classes at the University of Mississippi prior to COVID-19, but the difference disappeared in the years after 2020. Previously distinct trendlines of GPA-based predictions of earned-grade for online and in-person classes merged. Of particular concern, outcomes for in-person classes declined to match pre-COVID-19 online expectations, with lower-GPA students disproportionally impacted. Objective …

Study Of Different Treatment Strategies In Epidemic Models Using Nonlinear Model Predictive Control, Hector Puebla, Luis A. Ricardez-Sandoval, Priti Kumar Roy

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Boosting The Power Performance Of Microbial Fuel Cells By Using Dual Nanomaterial-Modified Carbon Felt Electrodes, Krishna Thapa, Wenyan Liu, Yuwei Zhang, David J. Westenberg, Yishu Zhou, Risheng Wang

Chemistry Faculty Research & Creative Works

Innovative design enhancements to microbial fuel cells (MFCs) are pivotal for improving their viability as renewable energy sources. This study introduces a dual approach to electrode modification, integrating polyaniline (PANI) and gold nanoparticles (AuNPs) on carbon felt (CF) anodes coupled with a unique cathode composed of DNA origami and chitosan. The synergistic effect of PANI and AuNPs significantly increases the hydrophilicity and conductivity of the anode, leading to a considerable surge in power density. Concurrently, the biocompatible DNA origami and chitosan-functionalized cathode facilitates efficient electron transfer without relying on conventional catalysts. Together, these modifications yield a 52.42% increase in the …

Ignis: A One-Dimensional Laminar Flame Code, Jansen P. Berryhill, Jacob K. Spinti, David O. Lignell

Faculty Publications

Laminar flame codes have an important role in combustion modeling. They can provide a fundamental understanding of flame dynamics and provide a basis for building subgrid scale models in turbulent flow simulations. This paper presents Ignis, an open-source laminar flame code with the capability to offload submodels, like soot formation and radiation, using external packages and libraries. Ignis is written in C++, is documented with Doxygen, and is available on GitHub. It contains three different flame formulations: diffusion flames, premixed flames, and laminar flamelets solved in the mixture fraction coordinate. An option to facilitate creation of a diffusion flame table …

Kinetics, Thermodynamics, And Biological Characterizations Of Hydrolysates Enzymatically Produced From Proteins Extracted From Microalgae, Hebah Al-Amodi

Theses

This thesis aims to explore the use of Zeolitic Imidazolate Framework-L (ZIF-L) as a support for immobilizing alcalase and its potency in producing protein hydrolysates. ZIF-L was synthesized at room temperature using an aqueous solution, and alcalase was immobilized through adsorption batch experiment. The successful immobilization of alcalase on ZIF-L was confirmed through Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The maximum adsorption capacity of alcalase on ZIF-L was determined to be 672.1 ± 5.5 mg g^-1 at 40°C using an initial protein concentration of 5 mg mL-1. Adsorption equilibrium data …

Valorization Of Food Waste Into Hydrogen Energy Through Supercritical Water Gasification: Generation Potential And Techno-Econo-Environmental Feasibility Assessment, Md Sanowar Hossain, Fairuz Wasima, Md Sharul Islam Khan Shawon, Monjur Mourshed, Barun K. Das

Research outputs 2022 to 2026

Food waste (FW) is a significant portion of the solid waste produced by cities, and it has become a global problem due to the poor management of food distribution and consumption. The improper disposal of FW in landfills precipitates pervasive global environmental predicamentsHowever, effective management strategies have the potential to convert this large amount of garbage into a very effective renewable energy source, particularly through the generation of environmentally friendly hydrogen. This study examines the capacity for energy generation and the practicality of hydrogen production in Bangladesh using supercritical water gasification technology. The findings indicate that approximately 489 MW of …

The Effect Of Organic Semiconductor Electron Affinity On Preventing Parasitic Oxidation Reactions Limiting Performance Of N-Type Organic Electrochemical Transistors, Maryam Alsufyani, Benjamin Moss, Claudia E. Tait, William K. Myers, Maryam Shahi, Katherine Stewart, Xiaolei Zhao, Reem B. Rashid, Dilara Meli, Ruiheng Wu, Bryan D. Paulsen, Karl J. Thorley, Yuanbao Lin, Craig Combe, Charlie Kniebe-Evans, Sahika Inal, Sang Young Jeong, Han Young Woo, Grant Ritchie, Ji-Seon Kim, Jonathan Rivnay, Alexandra F. Paterson, James R. Durrant, Iain Mcculloch

Chemical and Materials Engineering Faculty Publications

A key challenge in the development of organic mixed ionic-electronic conducting materials (OMIEC) for high performance electrochemical transistors is their stable performance in ambient. When operating in aqueous electrolyte, potential reactions of the electrochemically injected electrons with air and water could hinder their persistence, leading to a reduction in charge transport. Here, the impact of deepening the LUMO energy level of a series of electron-transporting semiconducting polymers is evaluated, and subsequently rendering the most common oxidation processes of electron polarons thermodynamically unfavorable, on organic electrochemical transistors (OECTs) performance. Employing time resolved spectroelectrochemistry with three analogous polymers having varying electron affinities …

Precision Bottlebrush Polymers: Synthesis, Characterization, And Structure-Property Relationship, Nduka D. Ogbonna

LSU Doctoral Dissertations

Bottlebrush polymers, a type of non-linear polymer characterized by densely grafted side chains on a linear backbone, offer a versatile platform for material design due to their unique thermomechanical and rheological behavior. Addressing the grand challenge of achieving structural precision for bottlebrush polymers remains crucial because traditional disperse mixtures are plagued with batch variability, limiting our ability to control their functions, and correlate theoretical predictions with experiments. To date, narrow-dispersity bottlebrush polymers remain highly heterogeneous, as they are typically synthesized from disperse linear building blocks.

To address this longstanding challenge of structural heterogeneity in brush polymers, the primary objective of …

Characterization Of Aromatic Stationary Phases For Uses In High Performance Liquid Chromatography, Anastasia Davis

Honors Theses

High Performance Liquid Chromatography (HPLC) is an analytical chemist technique used to separate a sample into its components to characterize and study a specific molecule or compound. Traditionally, High-Performance Liquid Chromatography in different industries, such as the environmental and pharmaceutical fields, uses stationary phases that are already well characterized, such as the C18 stationary phase for separation. However, aromatic stationary phases have recently been produced, which have phenyl groups bonded to the interior surface of the column. Still, they have not been well characterized because of how modern they are. This project characterized several aromatic stationary phases (Biphenyl, pentafluorophenyl, and …

Investigating The Effect Of Microwave Pretreatment On Bastnasite Grinding For Comminution Energy Reduction And Rare Earth Recovery, Kaveh Asgari, Qingqing Huang, Rick Q. Honaker, Edward Sabolsky

Chemical and Materials Engineering Faculty Publications

This study explored the impact of microwave pretreatment on the grinding efficiency of bastnaesite ore using a stirred mill. Bastnaesite ore was prepared using a staged crushing and sieving process, followed by microwave pretreatment in a specially designed microwave furnace system. Representative samples of the crushed ore underwent stirred mill grinding, with power draw measurements recorded and adjusted to reflect only the specific energy input required for grinding. Particle size distribution was analyzed periodically using laser particle size analysis. In addition, a Box–Behnken design was used to statistically assess the effects of various parameters on the results, ensuring a robust …

Size And Shape Dependence Of Hydrogen-Induced Phase Transformation And Sorption Hysteresis In Palladium Nanoparticles, Xingsheng Sun, Rong Jin

Chemical and Materials Engineering Faculty Publications

Phase transitions of metals in hydrogen (H) environments are critically import- ant for applications in energy storage, catalysis, and sensing. Nanostructured metallic particles can lead to faster charging and discharging kinetics, increased lifespan, and enhanced catalytic activities. However, establishing a direct causal link between nanoparticle structure and function remains challenging. In this work, we establish a computational framework to explore the atomic config- uration of a metal-hydrogen system when in equilibrium with a H environ- ment. This approach combines Diffusive Molecular Dynamics with an itera- tion strategy, aiming to minimize the system’s free energy and ensure uniform chemical potential across …

Process Development And Techno-Economic Analysis For Combined And Separated Co2 Capture-Electrochemical Utilization, Abdullah Al Moinee, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Combining CO₂ capture and utilization into a single unit operation offers a feasible solution for converting a sustainable feedstock into marketable commodity chemicals, while reducing energy requirements from separated processes. In this research, we developed a process model and performed a techno-economic analysis (TEA) for point-source CO₂ capture and electrochemical-based utilization in light olefins production under both separated and integrated scenarios. CO₂ containing flue gas from a 500 MW power plant was utilized as a feed while CO₂ utilization involved electrochemical reduction reactions to produce light olefins directly from CO₂. A meticulous analysis was …

Engineering The Coherent Phonon Transport In Polar Ferromagnetic Oxide Superlattices, In Hyeok Choi, Seung Gyo Jeong, Do-Gyeom Jeong, Ambrose Seo, Woo Seok Choi, Jong Seok Lee

Chemical and Materials Engineering Faculty Publications

Artificial superlattices composed of perovskite oxides serves as an essential platform for engineering coherent phonon transport by redefining the lattice periodicity, which strongly influences the lattice-coupled phase transitions in charge and spin degrees of freedom. However, previous methods of manipulating phonons have been limited to controlling the periodicity of superlattice, rather than utilizing complex mutual interactions that are prominent in transition metal oxides. In this study on oxide superlattices composed of ferromagnetic metallic SrRuO3 and quantum paraelectric SrTiO3 , phonon modulation by controlling the geometry of superlattice in atomic-scale precision is realized, demonstrating the coherent phonon engineering using structural and …

The Use Of Peracetic Acid And The Advanced Oxidation Process In Water Purification., Spencer Shipman

Electronic Theses and Dissertations

The Next Round Brewing project was a project that sought to use treated wastewater to make potable drinking water using peracetic acid (PAA) and the advanced oxidation process and break the stigma around reclaimed water. In experiments, PAA was an efficient biocide which reduced the level of pathogens to within EPA standards. When PAA was coupled with the advanced oxidation process all organic matter was also reduced to within acceptable levels, and no biocide was left over in the final product, meaning PAA properly dissociated into harmless byproducts. A series of experiments are presented that vary concentrations of PAA, effluent …

Biocargos: Capture And Release Gels For Room Temperature Cell Storage., Justin Jacobson

Electronic Theses and Dissertations

Currently, cryovials on dry ice or liquid nitrogen vapor transportation vessels are primary ways utilized to transport mammalian cells from one location to another. Due to the safety concerns of dry ice and liquid nitrogen, associated costly shipping charges, and limitations of proper packaging and labeling of materials, these conventional shipping techniques are unacceptable. It is urgent to develop a safe and environmentally friendly protocol to preserve and ship the biological samples from one place to another. In this research, a method was developed for an ecofriendly and safe protocol to preserve cancer cells. The cell viability of cell line …

Liquid Crystalline Collagen Assemblies As Substrates For Directed Alignment Of Human Schwann Cells, Homa Ghaiedi, Luis Carlos Pinzon-Herrera, Saja Alshafeay, Leonard Harris, Jorge Almodovar, Karthik Nayani

Chemical Engineering Faculty Publications and Presentations

Collagen is a key component of the extracellular matrix (ECM) and well-oriented domains of collagen are important for mimicking the local cell environment in vitro. While there has been significant attention directed towards the alignment of collagen, formation of large-scale oriented domains remains a key challenge. Type I collagen self-assembles to form liquid crystalline (LC) mesophases in acidic conditions at concentrations above 100 mg mL−1. The LC mesophase provides an efficient platform for large-scale alignment and patterning of collagen coated substrates. However, there still exist challenges related to solubilizing and processing of collagen at such high concentrations in order …

Review On Spontaneous Imbibition Mechanisms In Gas-Water Systems: Impacts On Unconventional Gas Production And Co2 Geo-Sequestration, Yihang Xiao, Zhenjiang You, Zhengtong Du, Yongming He, Jun Zheng, Yujie Yuan, Lei Wang

Research outputs 2022 to 2026

Spontaneous imbibition, a fundamental process in porous media, involves the displacement of a non-wetting phase by a wetting phase driven by capillary pressure. It plays a key role in various applications, particularly in unconventional gas production and greenhouse gas geo-sequestration. Despite extensive research in this area, conflicting results and explanations persist regarding imbibition phenomena, particularly in gas-water systems. This paper aims to address this gap by providing a comprehensive review of basic concepts, mechanical analyses, pore-filling patterns, front evolutions, and influencing factors associated with spontaneous imbibition. Mechanical factors including capillary force, viscous force, gravitational force, hydrostatic force, inertial force, capillary …

Zeta Potential Of Supercritical Co2-Water-Sandstone Systems And Its Correlation With Wettability And Residual Subsurface Trapping Of Co2, Jan Vinogradov, Miftah Hidayat, Mohammad Sarmadivaleh, David Vega-Maza, Stefan Iglauer, Lijuan Zhang, Dajiang Mei, Jos Derksen

Research outputs 2022 to 2026

Although CO2 geological storage (CGS) is thought to be one of the most promising technologies to sequester the anthropogenic CO2 to mitigate the climate change, implementation of the method is still challenging due to lack of fundamental understanding of controls of wettability, which is responsible for residual trapping of the gas and its flow dynamics. One of the key parameters that controls the wetting state is the zeta potential, ζ, at rock-water and CO2-water interfaces. ζ in systems comprising rocks, carbonated aqueous solutions and immiscible supercritical CO2 have not been measured prior to this study, where we detail the experimental …

The Impact Of Film Cooling On The Heat Release Within A Rotating Detonation Combustor, Shreyas Ramanagar Sridhara, Antonio Andreini, Marc D. Polanka, Myles D. Bohon

Faculty Publications

Rotating detonation combustors establish a detonation wave that continuously circulates inside a small annulus. The presence of the detonation wave and the downstream oblique shock within the small annulus coupled with high mass flow induces a high heat load to the combustor wall. Preliminary analysis shows that for higher thermal power, internal air cooling alone is not sufficient to remove the heat out of the walls to maintain them below the maximum temperature of the metal. A possible solution is to use film cooling to reduce the heat flux to the combustor walls. One issue, though, is that the introduction …

Modeling Reversible Volume Change In Automotive Battery Cells With Porous Silicon Oxide-Graphite Composite Anodes, Taylor R. Garrick, Brian J. Koch, Miguel A. Fernandez, Erin Efimoff, Hunter Teel, Matthew D. Jones, Mingjie Tu, Sirivatch Shimpalee

Faculty Publications

Automotive battery manufacturers are working to improve the individual cell and overall pack design by increasing durability, performance, and range, while reducing cost, and active material volume change is a key aspect that needs to be considered during this design process. Recently, silicon oxide-graphite composite anodes are being explored to increase total anode capacity while maintaining a tolerable amount of cell level reversible volume expansion due to the relatively lower reversible volume change of the silicon oxide compared to pure battery grade or metallurgical grade silicon. To predict the blended anode response and contribution to the overall cell volume change, …

Optimizing In-Situ Upgrading Of Heavy Crude Oil Via Catalytic Aquathermolysis Using A Novel Graphene Oxide-Copper Zinc Ferrite Nanocomposite As A Catalyst, Attia Attia, Ahmed Ashraf Soliman Eng., Mostafa Aboul-Fetouh Prof., Sayed Gomaa Prof., Tarek Aboul-Fotouh Prof.

Petroleum Engineering and Gas

Unconventional resources, such as heavy oil, are increasingly being explored and exploited due to the declining availability of conventional petroleum resources. Heavy crude oil poses challenges in production, transportation, and refining, due to its high viscosity, low API gravity, and elevated sulfur and metal content. Improving the quality of heavy oil can be achieved through the application of steam injection, which lowers the oil’s viscosity and enhances its flow. However, steam injection alone falls short of meeting the growing demand for higher-quality petroleum products. Catalytic upgrading is therefore being investigated as a viable solution to improve heavy oil quality. This …

Journal Of Electrochemistry Is Selected To Entering Ici Journals Master List, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Single Nanobubble Formation On Au Nanoelectrodes And Au@Ws2 Nanoelectrodes: Voltammetric Analysis And Electrocatalysis, Xian-Zhun Luo, Xiao-Hu Chen, Yong-Xin Li

Journal of Electrochemistry

Taking advantage of the extremely small size of the gold nanodisk electrode, the single hydrogen nanobubble generated on the surface of the nanoelectrode was studied to evaluate its hydrogen evolution performance. It was found that compared with the bare gold nanodisk electrode, the bubble formation potential of the gold nanodisk electrode modified with tungsten disulfide quantum dots (WS₂ QDs) on the surface was more positive, indicating that its hydrogen evolution activity was higher. Microdynamic model analysis shows that the average standard rate constant of the rate-determining step of the hydrogen evolution reaction of gold nanoelectrodes modified with WS_{2 …}

Goodbye With Tears! Deep Condolences To Academician Zhao-Wu Tian!, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

The Adviser Of Journal Of Electrochemistry Professor Christian Amatore Received The Chinese Government Friendship Award, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Tunable Blended Collagen I/Ii And Collagen I/Iii Hydrogels As Tissue Mimics, Paulina M. Babiak, Carly M. Battistoni, Leonard Cahya, Rithika Athreya, Jason Minnich Ii, Alyssa Panitch, Julie C. Liu

School of Chemical Engineering Faculty Publications

Collagen (Col) is commonly used as a natural biomaterial for biomedical applications. Although Col I is the most prevalent col type employed, many collagen types work together in vivo to confer function and biological activity. Thus, blending collagen types can better recapitulate many native environments. This work investigates how hydrogel properties can be tuned through blending collagen types (col I/II and col I/III) and by varying polymerization temperatures. Col I/II results in poorly developed fibril networks, which softened the gels, especially at lower polymerization temperatures. Conversely, col I/III hydrogels exhibit well-connected fibril networks with localized areas of fine fibrils and …

Joint Subarray Acoustic Tweezers Enable Controllable Cell Translation, Rotation, And Deformation, Liang Shen, Zhenhua Tian, Kaichun Yang, Joseph Rich, Jianping Xia, Neil Upreti, Jinxin Zhang, Chuyi Chen, Nanjing Hao, Zhichao Pei, Tony Jun Huang

Faculty Publications

Contactless microscale tweezers are highly effective tools for manipulating, patterning, and assembling bioparticles. However, current tweezers are limited in their ability to comprehensively manipulate bioparticles, providing only partial control over the six fundamental motions (three translational and three rotational motions). This study presents a joint subarray acoustic tweezers platform that leverages acoustic radiation force and viscous torque to control the six fundamental motions of single bioparticles. This breakthrough is significant as our manipulation mechanism allows for controlling the three translational and three rotational motions of single cells, as well as enabling complex manipulation that combines controlled translational and rotational motions. …