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Full-Text Articles in Chemistry

A Simple, Inexpensive Alkaline Method For Bacterial Dna Extraction From Environmental Samples For Pcr Surveillance And Microbiome Analyses, Abdulkarim Shwani, Bin Zuo, Adnan Alrubaye, Jiangchao Zhao, Douglas D. Rhoads Jan 2024

A Simple, Inexpensive Alkaline Method For Bacterial Dna Extraction From Environmental Samples For Pcr Surveillance And Microbiome Analyses, Abdulkarim Shwani, Bin Zuo, Adnan Alrubaye, Jiangchao Zhao, Douglas D. Rhoads

Poultry Science Faculty Publications and Presentations

DNA extraction for downstream molecular diagnostic applications can be an expensive, time-consuming process. We devised a method to quickly extract total bacterial DNA from environmental samples based on the sodium hydroxide lysis of cells with or without capture by magnetic beads for subsequent PCR or quantitative PCR. The final DNA extraction method using NaOH is extremely low-cost and can be completed in as little as 10 min at room temperature with dilution, or the DNA can be further purified using silica-coated paramagnetic beads. NaOH extraction was effective for Gram-negative and Gram-positive bacteria in samples from air, soil, sewage, food, laboratory …

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Interface Engineering Of Lithium Metal Anodes Via Atomic And Molecular Layer Deposition, Xiangbo Meng Jan 2024

Interface Engineering Of Lithium Metal Anodes Via Atomic And Molecular Layer Deposition, Xiangbo Meng

Mechanical Engineering Faculty Publications and Presentations

Rechargeable batteries are playing an ever-increasing important role in our society. Their performance (such as cell cyclability, safety, and lifespan) is critical for their applications. Among the various factors related to cell performance, interfaces, which ubiquitously exist between an electrode and an electrolyte, have some significant functions. They mostly evolve and degrade with cell cycling. Thus, an ideal interface should be physically and electrochemically stable and able to provide a compatible environment for electrolytes and electrodes in cells. To this end, interface engineering is needed and has become an important area. It has been achieved via different strategies. In the …

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Ionically Crosslinked Cellulose Nanocrystals By Metal Nitrates For The Preparation Of Stable Emulsions With Tunable Interface Properties, Joseph Batta-Mpouma, Gurshagan Kandhola, Jin-Woo Kim Dec 2023

Ionically Crosslinked Cellulose Nanocrystals By Metal Nitrates For The Preparation Of Stable Emulsions With Tunable Interface Properties, Joseph Batta-Mpouma, Gurshagan Kandhola, Jin-Woo Kim

Materials Science and Engineering Faculty Publications and Presentations

Biologically extracted cellulose nanocrystals (CNCs) are rod-like and amphiphilic materials with surface-exposed (hydrophilic sites) and hidden (hydrophobic sites) hydroxyl groups. These physicochemical characteristics make CNCs suitable for use as emulsifying agents to stabilize emulsions. Stable oil-in-water emulsions, using sulfated (i.e., – SO3−) CNCs that were ionically crosslinked with alkaline-earth (i.e., Mg 2+) or transition-d-block (i.e., Zn 2+) metal cations, were developed without the use of any synthetic surfactants or prior functionalization of pure CNCs with hydrophobic molecules. Various emulsion surface properties such as interfacial tension, surface charge, surface chemistry, as well as rheology were characterized. Ionically …

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Quantification Of Dye Degradation On Titanium Dioxide-Based Membranes, Elizabeth Carol Wood Dec 2023

Quantification Of Dye Degradation On Titanium Dioxide-Based Membranes, Elizabeth Carol Wood

Graduate Theses and Dissertations

The purpose of this study was to examine the dye degradation on the titanium dioxide (TiO2)-based membranes. While many studies have shown photocatalytic degradation of dye on TiO2 in solution, few studies have been reported on the solid TiO2 substrate. In this work, a new method is developed to quantify the dye degradation on TiO2-based membranes. A hydrothermal method is used to synthesize the photocatalytic TiO2 nanofibers; vacuum filtration is applied to fabricate a self-assembled membrane. Silver is incorporated into the nanofibers through in situ reduction before vacuum filtration to fabricate Ag/TiO2 membrane in an attempt to red shift the …

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University Of Arkansas, Chemistry And Biochemistry Department Research Publications, 2014- November 2023. 107p., Jeremy Smith, Lutishoor Salisbury Nov 2023

University Of Arkansas, Chemistry And Biochemistry Department Research Publications, 2014- November 2023. 107p., Jeremy Smith, Lutishoor Salisbury

University Libraries Faculty Publications and Presentations

This report provides a compilation of the research publications by the Chemistry and Biochemistry faculty for the period: 2014 - November 2023. The information was gathered from major databases in science and technology including Web of Science, SciFinder, Reaxys, PubMed, IEEE Explore and Engineering Index. At least one author in each of the publications has the CHBC department as its affiliation. It includes a table summarizing the research. The listing is organized according to type of publications within specific years.

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University Of Arkansas, Chemistry And Biochemistry Department Graduate Student Publications, 2018- November 2023. 39p., Jeremy Smith, Lutishoor Salisbury Nov 2023

University Of Arkansas, Chemistry And Biochemistry Department Graduate Student Publications, 2018- November 2023. 39p., Jeremy Smith, Lutishoor Salisbury

University Libraries Faculty Publications and Presentations

This report provides a compilation of the research publications by the Chemistry and Biochemistry (CHBC) Graduate students for the period: 2018-November 2023. It includes publications by the CHBC graduates and those where a CHBC faculty was the main advisor. It includes a summary of the research. The listing is organized according to type of publications within specific years.

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Flexible And Sewable Electrode Based On Ni-Co@Pani-Salphen Composite-Coated On Textiles For Wearable Supercapacitor, Touba Rezaee Adriyani, Ali A. Ensafi, B. Rezaei Nov 2023

Flexible And Sewable Electrode Based On Ni-Co@Pani-Salphen Composite-Coated On Textiles For Wearable Supercapacitor, Touba Rezaee Adriyani, Ali A. Ensafi, B. Rezaei

Chemistry & Biochemistry Faculty Publications and Presentations

Flexible electrodes with high deformability and energy density are critical for electronic textiles. The key factor for achieving high-performance supercapacitors with superior power and energy density is the evaluation of materials that exhibit exceptional capacitive performance. Herein, we have prepared Ni-Co nanoparticles at the surface of polyaniline-salphen (Ni-Co@PS). Then, followed by casting Ni-Co@PS on a conductive carbon cloth (CC) as a substrate through a facile in-situ polymerization strategy. The morphologies of Ni-Co@PS composite were characterized by different methods such as FE-SEM, XPS, XRD, BET, and electrochemical methods. This nanocomposite showed high tolerability and a large surface area with excellent behavior …

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Alkaline Pretreatment And Air Mixing For Improvement Of Methane Production From Anaerobic Co-Digestion Of Poultry Litter With Wheat Straw, Yuanhang Zhan, Jun Zhu, Yiting Xiao, Leland C. Schrader Sep 2023

Alkaline Pretreatment And Air Mixing For Improvement Of Methane Production From Anaerobic Co-Digestion Of Poultry Litter With Wheat Straw, Yuanhang Zhan, Jun Zhu, Yiting Xiao, Leland C. Schrader

Biological and Agricultural Engineering Faculty Publications and Presentations

Alkaline pretreatment (AL) and air mixing (air) both have the potential to improve anaerobic co-digestion (Co-AD) of poultry litter with wheat straw for methane production. In this study, the effects of the combination of AL (pH 12 for 12 h) and air mixing (12 mL·d−1) on the Co-AD process were investigated. The substrate hydrolysis was enhanced by AL, with soluble chemical oxygen demand increased by 4.59 times and volatile fatty acids increased by 5.04 times. The cumulative methane yield in the group of Co-AD by AL integrated with air (Co-(AL + air)), being 287 mL·(g VSadded) …

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Guar-Based Injectable Hydrogel For Drug Delivery And In Vitro Bone Cell Growth, Humandra Poudel, Ambar R. Rangumagar, Pooja Singh, Adeolu Oluremi, Nawab Ali, Fumiya Watanabe, Joseph Batta-Mpouma, Jin-Woo Kim, Ahona Ghosh, Anindya Ghosh Sep 2023

Guar-Based Injectable Hydrogel For Drug Delivery And In Vitro Bone Cell Growth, Humandra Poudel, Ambar R. Rangumagar, Pooja Singh, Adeolu Oluremi, Nawab Ali, Fumiya Watanabe, Joseph Batta-Mpouma, Jin-Woo Kim, Ahona Ghosh, Anindya Ghosh

Chemistry & Biochemistry Faculty Publications and Presentations

Injectable hydrogels offer numerous advantages in various areas, which include tissue engineering and drug delivery because of their unique properties such as tunability, excellent carrier properties, and biocompatibility. These hydrogels can be administered with minimal invasiveness. In this study, we synthesized an injectable hydrogel by rehydrating lyophilized mixtures of guar adamantane (Guar-ADI) and poly-β-cyclodextrin (p-βCD) in a solution of phosphate-buffered saline (PBS) maintained at pH 7.4. The hydrogel was formed via host-guest interaction between modified guar (Guar-ADI), obtained by reacting guar gum with 1-adamantyl isocyanate (ADI) and p-βCD. Comprehensive characterization of all synthesized materials, including the hydrogel, was performed using …

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The Bactericidal Activity Of A Novel Aneurinibacillus Aneurinilyticus Isolate Effectively Controls Foodborne Pathogens Campylobacter Jejuni And Listeria Monocytogenes, Peter M. Rubinelli, Rohana Liyanage, Jackson Lay, Jennifer C. Acuff Sep 2023

The Bactericidal Activity Of A Novel Aneurinibacillus Aneurinilyticus Isolate Effectively Controls Foodborne Pathogens Campylobacter Jejuni And Listeria Monocytogenes, Peter M. Rubinelli, Rohana Liyanage, Jackson Lay, Jennifer C. Acuff

Chemistry & Biochemistry Faculty Publications and Presentations

Human zoonotic infection with Campylobacter is a major cause of gastroenteritis in the United States and worldwide. Listeria monocytogenes causes a potentially fatal infection in humans and is often attributed to contaminated food. Genetic typing has demonstrated that Campylobacter infection is often associated with the consumption of contaminated poultry products, with Campylobacter often colonizing the poultry gastrointestinal tract, while listeriosis is commonly associated with the consumption of contaminated ready-to-eat (RTE) foods. In this study, a strain of endospore-forming bacterium (strain NH) that is bactericidal towards the human food pathogens Campylobacter jejuni and Listeria monocytogenes was identified and characterized. Transwell experiments …

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Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino Aug 2023

Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino

Biological Sciences Undergraduate Honors Theses

This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …

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Dual Ni/Co-Hemin Metal-Organic Framework-Prgo For High-Performance Asymmetric Hybrid Supercapacitor, Kimia Zarean Mousaabadi, Ali A. Ensafi, Erfan Naghsh, Jin-Song Hu, Behzad Rezaei Aug 2023

Dual Ni/Co-Hemin Metal-Organic Framework-Prgo For High-Performance Asymmetric Hybrid Supercapacitor, Kimia Zarean Mousaabadi, Ali A. Ensafi, Erfan Naghsh, Jin-Song Hu, Behzad Rezaei

Chemistry & Biochemistry Faculty Publications and Presentations

In this study, we conducted direct synthesis of a dual metal–organic framework (Ni/Co-Hemin MOF) on phosphorous-doped reduced graphene oxide (PrGO) to serve as an active material in high-performance asymmetrical supercapacitors. The nanocomposite was utilized as an active material in supercapacitors, exhibiting a noteworthy specific capacitance of 963 C g−1 at 1.0 A g−1, along with a high rate capability of 68.3% upon increasing the current density by 20 times, and superior cycling stability. Our comprehensive characterization and control experiments indicated that the improved performance can be attributed to the combined effect of the dual MOF and the …

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Next-Generation Nanopore Sensors Based On Conductive Pulse Sensing For Enhanced Detection Of Nanoparticles, Samuel Confederat, Seungheon Lee, Derr Vang, Dimitrios Soulias, Fabio Marcuccio, Timotheus I. Peace, Martin Andrew Edwards, Pietro Strobbia, Devleena Samanta, Christoph Wälti, Paolo Actis Aug 2023

Next-Generation Nanopore Sensors Based On Conductive Pulse Sensing For Enhanced Detection Of Nanoparticles, Samuel Confederat, Seungheon Lee, Derr Vang, Dimitrios Soulias, Fabio Marcuccio, Timotheus I. Peace, Martin Andrew Edwards, Pietro Strobbia, Devleena Samanta, Christoph Wälti, Paolo Actis

Chemistry & Biochemistry Faculty Publications and Presentations

Nanopore sensing has been successfully used to characterize biological molecules with single-molecule resolution based on the resistive pulse sensing approach. However, its use in nanoparticle characterization has been constrained by the need to tailor the nanopore aperture size to the size of the analyte, precluding the analysis of heterogeneous samples. Additionally, nanopore sensors often require the use of high salt concentrations to improve the signal-to-noise ratio, which further limits their ability to study a wide range of nanoparticles that are unstable at high ionic strength. Here, a new paradigm in nanopore research that takes advantage of a polymer electrolyte system …

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Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley Aug 2023

Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley

Graduate Theses and Dissertations

Poly(ionic liquid)s (PILs) are a fascinating subclass of strong polyelectrolytes formed from polymerizable ionic liquids. As a result of their unique properties and counterion exchangeability, PILs can exhibit conformation structure or material property changes in response to external stimuli such as changes in pH/ionic environment, magnetic fields, and electric potentials. In Chapter 1, a comprehensive review of PILs design as well as their stimuli-responsive behavior is provided. Additional motivation for each dissertation chapter is also discussed. In Chapter 2, magnetically responsive PILs (MPILs) are developed from complexing paramagnetic salts with a random PIL copolymer containing a metal-coordinating co-monomer, acrylamide. A …

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Addressing The Embeddability Problem In Transition Rate Estimation, Curtis Goolsby, James Losey, Ashkan Fakharzadeh, Yuchen Xu, Marie-Christine Düker, Mila Getmansky Sherman, David S. Matteson, Mahmoud Moradi Jun 2023

Addressing The Embeddability Problem In Transition Rate Estimation, Curtis Goolsby, James Losey, Ashkan Fakharzadeh, Yuchen Xu, Marie-Christine Düker, Mila Getmansky Sherman, David S. Matteson, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

Markov State Models (MSM) and related techniques have gained significant traction as a tool for analyzing and guiding molecular dynamics (MD) simulations due to their ability to extract structural, thermodynamic, and kinetic information on proteins using computationally feasible MD simulations. The MSM analysis often relies on spectral decomposition of empirically generated transition matrices. This work discusses an alternative approach for extracting the thermodynamic and kinetic information from the so-called rate/generator matrix rather than the transition matrix. Although the rate matrix itself is built from the empirical transition matrix, it provides an alternative approach for estimating both thermodynamic and kinetic quantities, …

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Cpsrp43 Is Both Highly Flexible And Stable: Structural Insights Using A Combined Experimental And Computational Approach, Mitchell Benton, Mercede Furr, Vivek Govind Kumar, Adithya Polasa, Feng Gao, Colin David Heyes, Thallapuranam Krishnaswamy Suresh Kumar, Mahmoud Moradi Jun 2023

Cpsrp43 Is Both Highly Flexible And Stable: Structural Insights Using A Combined Experimental And Computational Approach, Mitchell Benton, Mercede Furr, Vivek Govind Kumar, Adithya Polasa, Feng Gao, Colin David Heyes, Thallapuranam Krishnaswamy Suresh Kumar, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

The novel multidomain protein, cpSRP43, is a unique subunit of the post-translational chloroplast signal recognition particle (cpSRP) targeting pathway in higher plants. The cpSRP pathway is responsible for targeting and insertion of light-harvesting chlorophyll a/b binding proteins (LHCPs) to the thylakoid membrane. Upon emergence into the stroma, LHCPs form a soluble transit complex with the cpSRP heterodimer, which is composed of cpSRP43 and cpSRP54. cpSRP43 is irreplaceable as a chaperone to LHCPs in their translocation to the thylakoid membrane and remarkable in its ability to dissolve aggregates of LHCPs without the need for external energy input. In previous studies, cpSRP43 …

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The Alternating Access Mechanism In Mammalian Multidrug Resistance Transporters And Their Bacterial Homologs, Shadi A. Badiee, Ugochi H. Isu, Ehsaneh Khodadadi, Mahmoud Moradi Jun 2023

The Alternating Access Mechanism In Mammalian Multidrug Resistance Transporters And Their Bacterial Homologs, Shadi A. Badiee, Ugochi H. Isu, Ehsaneh Khodadadi, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

Multidrug resistance (MDR) proteins belonging to the ATP-Binding Cassette (ABC) transporter group play a crucial role in the export of cytotoxic drugs across cell membranes. These proteins are particularly fascinating due to their ability to confer drug resistance, which subsequently leads to the failure of therapeutic interventions and hinders successful treatments. One key mechanism by which multidrug resistance (MDR) proteins carry out their transport function is through alternating access. This mechanism involves intricate conformational changes that enable the binding and transport of substrates across cellular membranes. In this extensive review, we provide an overview of ABC transporters, including their classifications …

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Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers May 2023

Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers

Physics Undergraduate Honors Theses

Under continuous excitation, quantum dots exhibit random transitions between fluorescent ON states and non-fluorescent OFF states --- a phenomenon known as blinking. A physical description of the mechanism responsible for blinking that applies broadly to many types of quantum dots remains under debate. We study the blinking behavior of the non-toxic CuInS2 quantum dot, a system that has seen little investigation at the single-particle level. In particular, the optical properties of CuInS2 quantum are often improved by adding ZnS to the nanoparticles, but this addition leads to complex structural-optical property relationships that are even less understood. To probe the relationship …

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Developing Methods For Pattern Transfer In Photoelectrochemical Lithography, Ashlyn Descarpentrie May 2023

Developing Methods For Pattern Transfer In Photoelectrochemical Lithography, Ashlyn Descarpentrie

Chemistry & Biochemistry Undergraduate Honors Theses

The microprocessor industry has historically been driven by the goal of shrinking devices. To create features small enough to fit on such devices, photolithography has conventionally been used in the micropatterning of noble metal surfaces. Photolithography is a complicated and expensive process that involves a cleanroom, metallization processes, and photoresist. While this investment makes sense for high revenue applications, a number of microelectronic devices do not require nanometer-scale patterned features. Examples of such applications include specific types of antennae, sensing electrodes, and photocatalysts. Photolithography for these devices is thus too costly in both money and energy. The Coridan lab has …

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Low-Cost Microstereolithography 3d Printing With Microfluidic Microsampling Applications, Lauren Twombly May 2023

Low-Cost Microstereolithography 3d Printing With Microfluidic Microsampling Applications, Lauren Twombly

Chemistry & Biochemistry Undergraduate Honors Theses

The growing field of stereolithography 3D printing has welcomed a new age ofmicrofluidic device fabrication techniques. When compared to previous planar fabrication techniques such as soft-lithography, stereolithography 3D printing offers highly automated procedures, reduced fabrication times, and greater complexity of device features. To date, the greatest tradeoff for 3D printing in microfluidic device fabrication is poorer resolution when compared to soft-lithography which can produce feature sizes on the nanometer scale. The poorer resolution of 3D printing limits the feasible size of features. While highly sophisticated 3D printers are capable of achieving sub 10 μm resolution, these instruments are incredibly expensive …

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Detection Of Nitrogen Dioxide Via Graphene-Enhanced Raman Scattering, Spencer Hazeslip May 2023

Detection Of Nitrogen Dioxide Via Graphene-Enhanced Raman Scattering, Spencer Hazeslip

Chemistry & Biochemistry Undergraduate Honors Theses

This paper presents the development of a nitrogen dioxide (NO2) sensor that utilizes the phenomenon of graphene-enhanced Raman scattering (GERS). The sensor consists of monolayer graphene on a silicon wafer, functionalized noncovalently with Copper(II) 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine (CuTTPc) via the solution soaking method. A custom sensing chamber was constructed to enable Raman spectra to be collected during NO2 exposure. The response of the sensor was found to be linear between 10 and 100 ppm NO2, indicating that it could be used for both detection and quantification. Furthermore, the sensor was shown to be reusable after …

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Carbon Dioxide Reduction On Large Area Liquid Metal Gallium-Indium Electrocatalysts, Thomas Hollis May 2023

Carbon Dioxide Reduction On Large Area Liquid Metal Gallium-Indium Electrocatalysts, Thomas Hollis

Chemistry & Biochemistry Undergraduate Honors Theses

Carbon dioxide (CO2) is widely known as a greenhouse gas that contributes to global warming due to the burning of fossil fuels. The carbon dioxide reduction reaction (CO2RR) is widely studied to reutilize CO2 to useful products, including methane, ethane, and carbon monoxide. This project studies the use of liquid metal gallium-indium as an electrocatalyst to perform CO2 reduction to carbon monoxide (CO) or possibly solid carbon in various solutions. Gallium-indium is characterized and studied through its “wetting” properties and adhesion to substrate foil through the measurement of contact angles inside solution. These liquid …

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Design Of A Hyperstable Endocrine Acting Fibroblast Growth Factot, Sara Armstrong May 2023

Design Of A Hyperstable Endocrine Acting Fibroblast Growth Factot, Sara Armstrong

Chemistry & Biochemistry Undergraduate Honors Theses

A novel chimera protein, consisting of the C-terminus of Fibroblast Growth Factor (FGF) 21 and super FGF1, a mutant of the wild-type FGF1, was studied. The protein retained the stability of sFGF1 and the endocrine acting behaviors and binding efficiency of FGF21, so that it could be more practical for therapeutic uses as a wound healing and angiogenic agent. sFGF1- FGF21 was expressed and purified before utilizing various biophysical techniques to measure its stability, secondary and tertiary characteristics, and metabolic activity.

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Battery Design, Construction, And Characterization For Small Motor Use Focusing On Anodic Zinc For Electron Flow, Amber Veach May 2023

Battery Design, Construction, And Characterization For Small Motor Use Focusing On Anodic Zinc For Electron Flow, Amber Veach

Chemical Engineering Undergraduate Honors Theses

This thesis explores the construction, characterization, and application of anodic zinc batteries for powering a small electric motor for the ChemE Car competition. Two zinc galvanic cell batteries were studied: zinc-carbon and zinc-air batteries. Prototype batteries were constructed and tested for voltage, amperage, and power production. In the zinc-carbon trials, a 3:1 mixture of manganese dioxide and graphite was determined to be the best cathode for power production. The size which allowed for sufficient power while maintaining the smallest footprint on the car was a zinc can six cm tall and two cm in diameter. Analysis of paper zinc-air battery …

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Separation Of Organic Acids Through Direct Catalysis From Sugars, Katelyn Robinson May 2023

Separation Of Organic Acids Through Direct Catalysis From Sugars, Katelyn Robinson

Chemical Engineering Undergraduate Honors Theses

Society relies on plastic products, whether they are single use or durable. A downside of plastic is that the most common type is a product of oil and oil is not only a limited resource but also a climate-damaging resource. Polylactic acid (PLA) is a bio-based, biodegradable plastic. However, the process of converting biomass to polylactic acid polymer has the largest environmental impact of the PLA production process, so alternative methods of conversion are needed (Moretti et al., 2021). The polylactic acid polymer can be made with lactic acid, which can be converted from glucose.

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An Experimental Study Into Tholin's Solubility With Liquid Hydrocarbons On Titan, Katherine Dzurilla May 2023

An Experimental Study Into Tholin's Solubility With Liquid Hydrocarbons On Titan, Katherine Dzurilla

Graduate Theses and Dissertations

Titan’s production of organics in its atmosphere and the liquid hydrocarbon lakes present on its surface make it a prime target for astrobiologists. Many previous studies on laboratory analogs of these organics, called "tholins", have found amino acids, nitriles, and other building blocks necessary for life. The potential solubility of tholins in the lakes of Titan presents an opportunity to create physical and chemical changes within the organics. While the lakes of Titan are primarily comprised of nonpolar compounds (methane and ethane), many predict that very small amounts of polar hydrocarbons are also present. To better understand these processes, researchers …

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Dpd Guided Insight On The Formation Process Of Polyethersulfone Membranes By Nonsolvent Induced Phase Separation And The Effects Of Additives, Eric Ledieu May 2023

Dpd Guided Insight On The Formation Process Of Polyethersulfone Membranes By Nonsolvent Induced Phase Separation And The Effects Of Additives, Eric Ledieu

Graduate Theses and Dissertations

Dissipative particle dynamics (DPD), a coarse grain simulation method, was applied to the membrane formation process of non-solvent induced phase separation (NIPS) to gain further insight on the mechanism of certain variables and how they affect the final morphology. NIPS involves two solutions, an organic polymer dissolved in an organic solvent colloquially called the dope and an aqueous coagulation bath, brought into contact with one another. The solvents then mix, causing the polymer to fall out of solution as an asymmetric membrane with a dense surface layer and a more open subsurface layer in response to the decreasing solubility. Polyethersulfone …

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Dipole Cooperativity And Polarization Frustration Determine The Secondary Structure Distribution Of Short Alanine Peptides In Water, Ying Yuan, Feng Wang Apr 2023

Dipole Cooperativity And Polarization Frustration Determine The Secondary Structure Distribution Of Short Alanine Peptides In Water, Ying Yuan, Feng Wang

Chemistry & Biochemistry Faculty Publications and Presentations

The physical driving forces for secondary structure preferences of hydrated alanine peptide are investigated with B3LYP-D3(BJ) and the adaptive force matching (AFM) method. The AFM fit to the DFT surface, ALA2022, provides excellent agreement with the nuclear magnetic resonance scalar coupling constants from experiments. In turn, the model is used to gain insight into the physical driving forces behind secondary structure preferences of hydrated peptides. DFT calculations with and without the Conductor-like Screening Model (COSMO) show that the α helix is stabilized by solvent polarization due to dipole cooperativity. The two adjacent amide groups in β strand form a near-planar …

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Simulating A Flexible Water Model As Rigid: Best Practices And Lessons Learned, Raymond Weldon, Feng Wang Apr 2023

Simulating A Flexible Water Model As Rigid: Best Practices And Lessons Learned, Raymond Weldon, Feng Wang

Chemistry & Biochemistry Faculty Publications and Presentations

Two ways to create rigid versions of flexible models are explored. The rigid model can assume the Model’s Geometry (MG) as if the molecule is not interacting with any other molecules or the ensemble averaged geometry (EG) under a particular thermodynamic condition. Although the MG model is more straightforward to create, it leads to relatively poor performance. The EG model behaves similarly to the corresponding flexible model (the FL model) and, in some cases, agrees even better with experiments. While the difference between the EG and the FL models is mostly a result of flexibility, the MG and EG models …

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H-Conise2/Nc Dodecahedral Hollow Structures For High-Performance Supercapacitors, P. Salehan, Ali A. Ensafi, Z. Andikaey, B. Rezaei Feb 2023

H-Conise2/Nc Dodecahedral Hollow Structures For High-Performance Supercapacitors, P. Salehan, Ali A. Ensafi, Z. Andikaey, B. Rezaei

Chemistry & Biochemistry Faculty Publications and Presentations

The synergistic effect between metal ions and increasing the surface area leads to the fabrication of supercapacitor materials with high capacities. It is predicted that transition metal selenide compounds will be ideal electrode materials for supercapacitors. However, the defects of poor conductivity and volume expansion of the compounds are fundamental problems that must be solved. In this work, we successfully synthesized the cobalt–nickel selenide nitrogen-doped carbon (H-CoNiSe2/NC) hollow polyhedral composite structure using ZIF-67 as a precursor. The CoSe2 and NiSe2 nanoparticles embedded in the NC polyhedral framework offer a wealth of active sites for the whole …

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