Chemistry Commons^™

Renewable Energy Conversion: Organic Redox Flow Batteries And Electrocatalytic Carbon Dioxide Reduction, Camden R. Debruler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Steadily increasing global energy demands have pushed the industry to investigate renewable energy sources like solar and wind to help alleviate the strain on fossil fuel based non-renewable energy sources while also reducing carbon emissions. However, the energy producing power of these renewable technologies is limited by factors such as weather and the day-night cycle. Additional energy storage technologies are needed which are capable of storing excess energy during periods of high productivity, and delivering it when production rates fluctuate.

Batteries represent one possible energy storage device to meet this need. Specifically, redox flow batteries (RFBs) offer advantages in terms …

Development Of High Throughput Assays For Identification And Evaluation Of Small Molecule Inhibitors Of Microrna-31 Expression, Jackline A. Onyango

Masters Theses

Dysregulated expression of miRNAs has been linked to numerous cancers. On the other hand, miRNAs are potential drug targets due to the ability of their precursor molecules to fold into ligand binding structures. Small-molecule modulators of miRNAs offers opportunity for the development of new therapeutic agents and tools to further probe the mechanisms of miRNA functions. To facilitate the identification of miRNA modulators, the appropriate screening systems are needed, which would be adaptable for high-throughput applications, and allow for quantitative measurements. In this text, we present a molecular beacon-based assay to identify molecules that inhibit miRNA-31 processing by Dicer and …

Novel N-Derivatized-7-Nitroindolines For The Synthesis Of Photocleavable Crosslinkers, And For Solid Phase Peptide Synthesis, Hector Patricio Del Castillo

Open Access Theses & Dissertations

7-Nitroindoline-based photochemistry has focused mostly on N-acyl-7-nitroindolines, which have been used as photocleavable protecting groups for carboxylic acids that can be efficiently removed by illumination with UV-light. They offer an alternative to the more commonly used o-nitrobenzyl-based photocleavable protecting groups. N-acyl-7-nitroindolines can also be used as photochemical acylating agents in inert solvents. For example, they have found application in peptide fragment condensation, the convergent synThesis of N-glycopeptides, and the synThesis of peptide thioesters, forming amide and thioester bonds with amine and thiol nucleophiles, respectively, under neutral conditions. The photochemical activation of N-acyl-7-nitroindolines can occur with UV light (λ = 350 …

Metastable State Photoacids And Ultrasound Responsive Carbon Monoxide Releasing Polymer Micelle, Osamah Zaid Saleh Alghazwat

Theses and Dissertations

This dissertation described my Ph.D. work on the development of a novel metastable state photoacids (mPAH), which can be activated by near infrared light and a reversible mPAH switched by different wavelengths of light. Also, it described the development of a micelle that responded to ultrasound to localized carbon monoxide CO delivery. An introduction of metastable state photoacid is given in Chapter 1. In Chapter 2, described my work on the development of a novel mPAH, which can be activated by near infrared light is an important factor for various biological functions. mPAH was designed and synthesized with a donor-acceptor-donor …

33-Kda Anxa3 Isoform Contributes To Hepatocarcinogenesis Via Modulating Erk, Pi3k/Akt-Hif And Intrinsic Apoptosis Pathways, Chunmei Guo, Nannan Li, Chengyong Dong, Liming Wang, Zhaopeng Li, Qinlong Liu, Qinglai Ma, Frederick T. Greenaway, Yuxiang Tian, Lihong Hao, Shuqing Liu, Ming Zhong Sun

Chemistry

Introduction: As a member of annexin family proteins, annexin A3 (ANXA3) has 36-kDa and 33-kDa isoforms. ANXA3 plays crucial roles in the tumorigenesis, aggressiveness and drug-resistance of cancers. However, previous studies mainly focused on the role of total ANXA3 in cancers without distinguishing the distinction between the two isoforms, the role of 33-kDa ANXA3 in cancer remains unclear. Objectives: Current work aimed to investigate the function and regulation mechanism of 33-kDa ANXA3 in hepatocarcinoma. Methods: The expressions of ANXA3, CRKL, Rac1, c-Myc and pAkt were analyzed in hepatocarcinoma specimens by Western blotting. The biological function of 33-kDa ANXA3 in the …

Investigating The Effects Of Catalytic Activity In Mycobacterium Tuberculosis Indole-3-Glycerol Phosphate Synthase In Wildtype, N189l, And E57d Variants, Sarah S. Cho

Theses, Dissertations and Culminating Projects

Indole-3-glycerol phosphate synthesis (IGPS) is an enzyme that catalyzes the ring closure in 1-(o-carboxylphenylamino)-1-deoxyribulose 5-phosphate (CdRP). Multiple steps are expected to be involved in formation of the pyrrole ring including dehydration, decarboxylation, cyclization, and condensation. IGPS is an essential protein in the pathogen Mycobacterium tuberculosis and a potential target in the treatment of drug-resistant tuberculosis. In order to better understand the function of Mycobacterium tuberculosis IGPS (mtIGPS), we introduced single-point mutations into active site residues. This was based on the hypothesis that introducing mutations would affect the catalysis in a way where we would be able to obtain more information …

Vertical Metal Distributions In Brownfield Soils Drive Enzyme Activities And Plant Success, Eshariah N. Dyson

Theses, Dissertations and Culminating Projects

The distribution of contaminants in polluted soils can vary through depth. We measured the vertical distributions of heavy metals and enzyme activities in the top 10 cm of side-by-side, vegetated and barren brownfield soils. The data showed metals significantly accumulated in the top 2 cm of barren soil and uniformly distributed through vegetated soil. When planted, germination rate was significantly lower in the previously barren soil, with the metal layer intact, compared to mixed barren soil. These data suggest a feedback loop in which plant roots redistribute metals, diluting metal-rich regions, yet germination remains initially limited by a metal cap. …

A Project To Dye For : Differentiation Of Dyed And Non-Dyed Human Hairs Using Atr Ft-Ir Spectroscopy, Joseph John Greco

Legacy Theses & Dissertations (2009 - 2024)

IR spectroscopy is widely utilized for forensic purposes due to the chemical fingerprint the method provides. ATR FT-IR spectroscopy is particularly advantageous because it allows for spectra to be collected quickly, accurately, and perhaps most importantly for forensics, non-destructively. Human hair is commonly collected at a crime scene, and further analyzed using DNA analysis and microscopy. However, these techniques have limitations. In the past ATR FT-IR spectroscopy has shown promise in the analysis of human hair for forensic purposes. In this study, the differentiation of undyed hair versus dyed hair classes of varying colors based on their IR spectra were …

Polymers In Drug Delivery Systems, Aashay Paresh Pratap

Legacy Theses & Dissertations (2009 - 2024)

Conventional drug delivery is associated with challenges such as low bioavailability, reduced half-life, nonspecific interactions, high immunogenicity, and degradation of drug before reaching the target. Modern drug delivery systems are designed to overcome the challenges of conventional drug delivery methods. Polymers play a crucial role in the development of modern drug delivery systems. Polymers form delivery vehicles that improve the therapeutic efficacy and reduce the side effects of a drug. Furthermore, it is possible to control the release of drug by using the delivery vehicles. Polymeric vehicles exist in different forms such as polymeric nanoparticles, hydrogels, and vesicles. Each form …

The Business Of Chemistry: The Effect Of Chemical Innovation On The U.S. Cosmetics Market, Tania Gonzalez

Chemistry

This study discusses the relationship between two distinct fields of study: chemistry and economics. Chemistry is a business in itself and has major effects on the US economy. Examining the U.S cosmetics market and the recent development of organic products will show the effect on market growth and the growing importance of organic cosmetics in the United States. The recent awareness and concern for eco-friendly and safer ingredients fueled by millennials is discussed. The average annual expenditure in the U.S. cosmetics market is examined and inflation is taken into account. The purpose is to show the importance of research in …

Comparison Of Raman Spectra Of Smokeless Powders For Cartridge Differentiation, Nathan Bartlett

Chemistry

As crimes involving firearms continue to be prevalent, forensic methods processing firearms evidence must keep pace with the changes in said evidence. Scanning Electron Microscopy with Energy Dispersive Spectroscopy, or SEM-EDS, is a method that targets the inorganic portions of gunshot residue (GSR) evidence, namely lead, barium, and antimony, to characterize a cartridge used at a crime scene, and was the most often used analysis method for characterizing ammunition cartridges. The rise of lead-free ammunition has made it so that SEM-EDS alone is not sufficient for the characterization of inorganic gunshot residue (IGSR), and studies have shifted towards being able …

Development Of Nucleic Acid Aptamers To Inhibit Bacterial Efflux Pumps, Emilie A. Moses

Honors Theses

Multidrug resistance in bacteria, defined as the ability of a bacterial strain to resist the killing effects of more than one antibiotic, represents a major threat to global healthcare. Every year in the United States, two million people are infected with a multidrug resistant strain of bacteria. According to the Center for Disease Control (CDC), out of those two million people, about 35,000 will die from their infection. Thus, these multidrug resistant diseases are considered by the CDC to be the most dangerous diseases in the world. While multidrug resistance can occur through several different mechanisms, a major contributor to …

Developing A Microdialysis Sampling-Based Biofilm/Macrophage Co-Culture Model, Alda Diaz Perez

Graduate Theses and Dissertations

The host immune system and bacterial cells are known to interact during the human lifetime. Bacteria secrete a wide variety of signaling molecules, known as quorum sensing (QSC) molecules, that modulate the host immune system. While immune-biofilm interactions involve this chemical signaling network, the mechanisms through which this occurs are not well understood. This work aimed to develop a new method that can be used not only in vitro settings but also in vivo. The microdialysis sampling technique has widely been used in in vitro and in vivo settings in humans, mice, and rats for the collection of neuropeptides, cytokines, …

Oriented External Electric Field (Oeef) Tuning Of Unsubstituted Azoheteroarene Photoswitching Performance., Irma Avdic

College of Arts & Sciences Senior Theses

Azoheteroarenes are relatively new photoswitchable compounds, where one of the phenyl rings of an azobenzene molecule is replaced by a heteroaromatic five-membered ring. Although few studies have been performed, recent findings on methylated azoheteroarenes show that these photoswitches have great potential in various optically addressable applications. Thermal stability of molecular switches is one of the primary factors considered in the design process. For the purposes of quick information transmission in materials science, the thermal (Z – E) relaxation process should be as short as possible. On the other hand, molecular memory storage devices prefer long Z - E relaxation times. …

The Evaluation Of Environmental Contaminants Using Static Headspace Gas Chromatography Mass Spectrometry, Vacuum Ultraviolet Detection, Emmanuel Varona -Torres

Chemistry & Biochemistry Dissertations - Archive

In analytical chemistry the term “headspace” refers to the vapor that forms above a sample (liquid or solid) in a closed container. Headspace (HS) sampling is the method to promote partition between volatile components from the sample matrix and then analyzed by gas chromatography (GC). HS is an excellent technique to introduce a “clean” vapor sample into the GC and avoids introduction of non-volatile components from the sample matrix and often used for determination of volatile organic compounds (VOCs) with minimal or no additional sample preparation. Concerns about the environmental impact of fossil fuel extraction techniques (i.e., hydraulic fracturing and …

Heavy Metals In Ends Liquids: A Comparative Analysis Of Products From The United States, England, Canada, And Australia, Ashleigh Coggins-Block

Forensic Science Theses

The International Tobacco Control (ITC) Policy Evaluation Project 4-Country Survey, which this thesis is a part of, aims to compare policies and electronic nicotine delivery system (ENDS) products between the United States, England, Canada, and Australia. Since they can pose many serious health risks, this thesis investigated the presence of and source of heavy metals, including lead, nickel, chromium, and cadmium, in ENDS e-liquids. The source of these metals in ENDS e-liquids has been disputed between cultivated tobacco used to derive nicotine and the metal parts of ENDS devices. ENDS purchased in 2017 from each of the four countries of …

Synthesis And Characterization Of Functiona Materials For 3d Printed Composites, Elizabeth Irene Reza

Open Access Theses & Dissertations

The following body of work encompasses the synThesis, upscaling, additive manufacturing, and characterization of microspheres as functional fillers incorporated into polymer syntactic foams. Synthesizing microspheres permits control over morphology, dispersion of particles, and size while the use of direct write manufacturing allowed for the controllability of filler orientation. Two different syntactic foams were developed from similar methodologies: (1) a silicone syntactic foam (2) epoxy syntactic foam. The silicone epoxy foam showed an increasing in damping and elastic modulus. The epoxy syntactic foams showed an enhanced thermal and electrical properties.

College Of Natural Sciences Newsletter, May 2021, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 2, Issue 5.

Page 1 Dean's Message
Page 2 - 3 Awards & Recognition
Page 4 Research Spotlight: Dr. Xiaoyang Zhang
Page 5 Upcoming Retirements
Page 6 - 7 Geography Alumni Social, Recent Media Coverage
Page 8 Open PRAIRIE Data
Page 9 - 11 Spring 2021 Dean's List and Academic Recognitions

Synthesis Of A Dd-Π-Aa Organic Dye For Dye-Sensitized Solar Cells, Hope Lovell

Honors Theses

This project investigates the synthesis of a DD-π-AA (dual donor/dual acceptor) organic dye as a potential sensitizer for dye-sensitized solar cells (DSCs). The design of this dye was based off previous research that found dual donor/dual acceptor dyes exhibited promising results when used in a DSC. The donor groups, acceptor groups, and π-bridge were chosen for their stability, ability to absorb in the near-infrared (NIR) region, and intramolecular charge transfer (ICT) abilities.

While many components of the dye were synthesized, the final stages of the synthetic scheme were not completed due to the loss of time from COVID-19. Had the …

Comparative Analysis Of Azo Dye Restriction In The International Textile Industry, Kayla Demark

Apparel Merchandising and Product Development Undergraduate Honors Theses

Azo dyes are the most used type of dye in the textile industry. Some of these dyes have the potential to be extremely toxic to both human health and the environment. While regulations of these dyes vary across the world, it is suggested that not enough is being done to protect consumers and the environment from potentially harmful azo dyes (Rawat et al., 2016). It is the responsibility of apparel companies to ensure that their products that contain azo dyes are safe for consumers.

The purpose of this study was to understand how azo dyes and their by-products are restricted …

Isolated Point Discharges Into Coastal Swashes As Nutrient Sources To Coastal Waters, Mary E. Olsen

Honors Theses

Coastal water quality in the Grand Strand of South Carolina is directly influenced by human activities. Nutrient-rich runoff, stemming from numerous anthropogenic sources, finds its way into coastal waters through freshwater inputs often through tidal creeks, termed swashes. In order to better describe the amount of nutrient inputs into Singleton Swash and White Point Swash, we examine anthropogenic runoff from isolated identifiable point discharges and their nutrient concentrations. We report concentrations of dissolved inorganic nitrogen (DIN, as the sum of nitrate, nitrite and ammonium) and phosphate in discharge and creek water. We hypothesize that nutrient concentrations of isolated, minor point …

Synthesis Of Bulky And Polar Galactonoamidines For The Inhibition Of The Human Α-Galactosidase, Ifedi Orizu

Graduate Theses and Dissertations

Glycosidases are amongst the most abundant enzymes in nature. This is due to their role in the degradation of carbohydrates which are the major source of carbon or earth. The absence or malfunction of glycosidases is implicated in numerous diseases such as cancers, diabetes, and lysosomal storage disorders, which make them important drug targets for study in medicinal chemistry. The seminal work by Pauling and Wolfenden showed that enzymes bind to their substrate at the transition state with very strong affinity. Wolfenden estimated the dissociation constant to be around 10-22M. This encouraged the design of glycosidase inhibitors which mimicked one …

Synthesis Of A Zinc Dipyrrin Complex For Photocatalytic Reduction Of Co2, Sylvia Meredith

Undergraduate Honors Theses

Zinc dipyrrin complexes have the potential to act as cheap, effective photosensitizers. Synthesizing and studying different types could lead to more efficient solar energy harvesting processes, especially the production of solar fuel. Here, two attempts to synthesize 1,3,7,9-tetraphenyl-5-mesityldipyrromethene are reported and discussed. According to ¹H NMR, the first synthesis attempt was not successful. The second synthesis attempt was not purified effectively, so ¹H NMR produced inconclusive results. Further purification strategies or alternate synthesis methods are required.

Analyzing The Lysergic Acid Amide Content Extracted From The Seeds Of Argyreia Nervosa Via The Use Of Lc-Ms, Elisabeth Barone

Forensic Science Master's Projects

Psychedelic plant use by humans can be traced back centuries to the times when early cultures used these plants in activities ranging from healing rituals to religious ceremonies. In recent years, several of these plants have reemerged on the drug scene and are currently being marketed as “legal highs” (since the plant seeds are legal to purchase through a variety of online vendors). With the growing number of internet forums where recreational drug users can write about their experiences and share them with others, it has become relatively simple for almost anyone to obtain the materials necessary to experience a …

Crystal Structure Of Tris, Colin T. Hartgerink, Richard J. Staples, Carolyn E. Anderson

University Faculty Publications and Creative Works

The title ketenyl­idene, [Au3(C2O)(C26H35O2P)3](C2F6NO4S2), was obtained upon exposure of [2-(di­cyclo­hexyl­phosphino)-2′,6′-dimeth­oxy-1,1′-biphen­yl]gold(I) bis­(tri­fluoro­methane­sulfon­yl)imide to acetic anhydride at elevated temperature. The ketenyl­idene bridge caps the tri-gold cluster. The title compound has provided crystals that upon analysis represent the first tri-gold ketenyl­idene with atomic distances indicative of bonding inter­action between the gold atoms.

The Impact Of Service-Learning On General Chemistry Ii Students At The University Of Nebraska At Omaha, Kayla Rud

Theses/Capstones/Creative Projects

Service-learning has been shown to enhance academic and leadership skills while promoting community engagement and exposing students to different career opportunities (Esson et al., 2005). While the benefits of service-learning courses are clear, few STEM courses include service-learning components (Esson et al., 2005). Here, students in a totally online 2nd semester UNO chemistry course completed a service-learning project where they remotely led a live, inquiry-based STEM activity for Girl Scouts. To quantify the impact of service-learning on professional development, future career plans, and future volunteerism, a series of pre and post surveys were administered. Paired-sample t-tests revealed a statistically significant …

Synthesis, Characterization, And Reactivity Of Organometallic Complexes For Catalytic Carbon-Hydrogen Bond Activation, Sophia Neglia

Honors Theses

Styrene can be produced directly from benzene and ethylene through an atom economical oxidative hydroarylation process. In this process, an electrophilic homogeneous transition metal catalyst activates the C-H bond in benzene. I propose to explore this reaction in two fronts: 1) the synthesis of electron-poor trans-spanning bidentate pyridine ligands and 2) the computational study of pyridine-functionalized bidentate diimines. The trans-spanning ligand will utilize either a Ru(II) or Co(III) metallohinge with cis-coordinated 2-ethynylpyridine ligands. The complex [(p-cym)Ru(PMe3)(C2-2-py)2] (1) where (p-cym = para-cymene and C2-2-py = 2-ethynylpyridine) can be prepared from (p-cym)Ru(PMe3)(Cl)2 and HC2-2-py in the presence of lithium bis(trimethylsilyl)amide (LiHMDS). Complex …

Understanding Shear Thinning Using Brownian Dynamics Simulation, Mackenzie Nicole Wall

Honors Theses

In this work, we study the changes in structure during the shear thinning regime using Brownian Dynamics with a simple steady-state shear flow of binary charged colloidal suspension. Previous research has analyzed the viscosity, radial distribution, elasticity and plasticity of materials with rheo-SANS experimentation; however, less research has been conducted to replicate the experiment through computer simulations. With Brownian Dynamic Simulation, this study was able to reproduce the results obtained in a recent rheo-SANS experiment and it also explored the viscosity, radial distribution, elastic and plastic behavior of a system under different parameters. The comparison of simulated data with experimental …

The Effect Of The Apolipoprotein A1 (Apoa1): The Stability And Folding In Potassium Chloride Environment, Alexandra Paladian

Honors Theses

Healthy levels of potassium chloride (KCl) can significantly affect the workings of the cholesterol level of the human body and how they pertain to an individual person. The search for a better salt additive for the human diet can provide a better option for people who experience high cholesterol levels and heart disease. The study focuses on the experimental design of the Molecular Dynamic (MD) simulation of the Apolipoprotein A1 (APOA1) in the potassium ion solution environment to determine the stability and folding of the protein. The study also compares its data to the previous experimental design of chloride ions …

Molecular Dynamic Simulation Of The Complex Folding Patterns Of Apolipoprotein A1 In Various Concentrations Of Potassium Chloride, Hannah Holmberg

Honors Theses

Apopliprotein or ApoA-1 is a complex lipoprotein that functions in the removal of cholesterol from the blood, removing cholesterol from the area around white blood cells and promoting the excretion of lipids through the lymphatic system. Previous research has found that ApoA-1 shows both folded and unfolded conformations depending on the concentration of NaCl in solution in the water around it. The protein was studied using molecular dynamics simulations. Once this state of equilibrium was reached, various structural properties of the protein were measured including the radius of gyration and the radial distribution function. The goal of the project was …