Chemistry Commons^™

Enhancing Urban Water Quality Through Biological-Chemical Treatment: Aquatic Macroinvertebrate Community And Temporal Chlorophyll-A Response, Matthew Chaffee

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

With a growing human population, urbanization is impeding a plethora of natural waterways. Of these, urban ponds play a vital role in nutrient sequestration, flood prevention, and habitat sanctuaries. However, nutrient loading can reduce habitat effectiveness and promote harmful algae blooms. To reduce internal nutrient loads, a biological-chemical treatment strategy consisting of floating treatment wetlands (FTWs) and lanthanum were applied to two urban retention ponds, Densmore and Wilderness Ridge Ponds. To measure effectiveness, chlorophyll-a samples were collected and correlated with Sentinel-2. A novel band algorithm termed 3BR1 produced a strong correlation (R² = 0.72) to physical chlorophyll-a …

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part I: Theoretical Underpinning, Victor Christianto, T. Daniel Chandra, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1,. 2, 2022), Our universe is but one page in a large book [4]. For example, things and Beings can travel between Universes, intentionally or unintentionally. In this short remark, we revisit and offer short remark to Neil’s ideas and trying to connect them with geometrization of musical chords as presented by D. Tymoczko and others, then to Escher staircase and then to Jacob’s ladder which seems to point to possibility to interpret Jacob’s vision as described in the ancient book of Genesis …

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The present article was partly inspired by G. Pollack’s book, and also Dadoloff, Saxena & Jensen (2010). As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1, No. 2, 2022), for example, things and Beings can travel between Universes, intentionally or unintentionally [4]. In this short remark, we revisit and offer short remark to Neil Boyd’s ideas and trying to connect them with geometry of musical chords as presented by D. Tymoczko and others, then to Escherian staircase and then to Jacob’s ladder which seems to pointto possibility to interpret Jacob’s vision …

Green Analytical Methods For The Determination Of Perfluorocarboxylic Acids (Pfcas) And Fluorotelomer Alcohols (Ftohs) In Water, Ahsan Habib

Open Access Theses & Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic organic compounds manufactured for their heat, water, and stain-resistant properties. PFAS can be found ubiquitously in the environment because they are widely used in everyday consumer products such as fast-food wrappers, non-stick cookware, stain-resistant products, cosmetics, aqueous film-forming foams, etc. As a result, PFAS are commonly detected in surface water, wastewater, and biosolids from wastewater treatment plants (WWTPs). These are the direct sources of PFAS contamination in drinking water supplies, which are substantial sources of human exposure. Among these PFAS chemicals, two major groups are perfluoroalkyl carboxylic acids (PFCAs) …

Computation-Assisted Molecular Discovery For Biomedical Applications: Seeking Small Molecules And Dna Sequences With High Affinity Target Binding, Payam Kelich

Open Access Theses & Dissertations

Binding affinity between two molecules is an essential property in drug and sensor discovery. Several computational and experimental methods exist to find molecules with high binding affinities to desired target molecules. These methods are often complementary, where fast computational methods can be used for the initial screening of molecules, and experimental methods can then screen and determine the molecules of interest and sometimes define the structures of bound complexes. After these steps, computational methods, like molecular dynamics (MD) simulations, can provide detailed insights into atomic interactions and binding, and machine learning approaches can analyze experiment-derived data to discern patterns and …

Sterically Encumbering Ligands For The Synthesis And Stabilization Of Iron Nitride And Iron Oxo Compounds, Asiel Mena

Open Access Theses & Dissertations

The study of iron-nitrides has been found to be very attractive due to their potential role in processes like Haber-Bosch and nitrogen fixation by nitrogenase. The role of iron-nitrides in these processes is yet not well understood, and the fact that only handful of terminal iron-nitrides have been isolated or spectroscopically detected motivates us to study this type of systems, since much remains to be learned about the electronic and structural factors that affect the chemistry of the Feâ?¡N bond. Recently in our group, by using a super-bulky guanidinate ligand (LAr*), the obtention of an iron-nitride ([LAr*]FeN(py) (LAr* = (Ar*N)2C(NCtBu2), …

Synthesis And Characterization Of Acetaminophen-Derived Nanoparticles: A Novel Approach To Inhibit Fibril Formation, Hannia Elena Mendoza-Dickey

Open Access Theses & Dissertations

In the realm of nanotechnology, nanoparticles (NPs), have garnered significant notoriety in recent scientific research due to their unique physical and chemical properties, such as fluorescence emissions, nanoscale dimensions (typically <1000 nm), ease of surface modification, and biocompatibility. Nanoparticles have shown their potential across a variety of areas, including advanced industrial applications and cutting-edge biomedical research. Considering their cost-effective synthesis, they have shown promise as therapeutic agents for a variety of bioimaging and biomedical applications. This thesis describes the synthesis and detailed analysis of acetaminophen-derived nanoparticles. Techniques such as Dynamic Light Scattering (DLS), Thioflavin T (THT) assay, Attenuated Total Reflectance Infrared Spectroscopy (ATR-IR), 1H NMR spectroscopy, and Ultraviolet-Visible Spectroscopy (UV-VIS) were utilized for structural and functional assessments. Acetaminophen derived nanoparticles (ANPs) exhibit potential to hinder the amyloidogenic conversion of soluble amyloid-forming proteins into their toxic form. The novelty of this research focuses on the utilization of chemical structures capable of traversing the Blood Brain Barrier (BBB) to mitigate xenotoxicant-induced neuronal damage, a notable contributor to neurodegenerative disorders. This thesis describes the synthesis and characterization of acetaminophen derived-nanoparticles (ANPs). Our nanoparticles possess anti-amyloidogenic properties as evidenced by their ability to disrupt in the soluble-to-toxic trajectory of HEWL. The prevalence and evolution of amyloid fibrils are consistent features in the pathology of neurodegenerative diseases such as Parkinson's disease (PD), Alzheimerâ??s Disease (AD), and Huntingtonâ??s Disease (HD), as well as metabolic disorders like Type 2 diabetes (T2D). The relationship between amyloidogenic pathways and these disorders highlights the imperative for enhanced understanding and the formulation of specific therapeutic interventions.

Study Of Human Circadian Protein (Hrory) And Lipid-Protein Interaction In Giant Virus (Pbcv-1), Laila Noor

Open Access Theses & Dissertations

Project 1: Circadian rhythm is a 24-hour cycle that regulates physical and behavioral changes such as sleep-wake patterns in humans, tailoring the daily light and dark changes. Long-term disruption in circadian rhythms can cause sleep disorders such as sleep apnea, insomnia, et al. Limited research has been done on potential drugs to treat against circadian related sleep disorders. Inside the cell at molecular level, the circadian rhythm is regulated by interlocked time-delayed feedback loops, which involve positive and negative transcriptional regulators. Experimental results showed transcriptional factors Retinoic Acid Receptor-Related Orphan Receptors (RORs) improve the stability and functionality of the circadian …

Upcyclying Of Polyethylene Terephtalate By Addition Of Thermoplastic Elastomer, Diego Francisco Bermudez

Open Access Theses & Dissertations

Continual overconsumption of single-use plastics has generated challenges of solid waste management across the United States. Common plastic waste management solutions, such as landfill, have caused the migration of contaminants into the environment consequently affecting not only the health of wildlife, but also that of human beings. Alternative strategies for the handling of single-use plastic such as polyethylene terephthalate (PET), used in the food packaging industry, can ultimately help mitigate the noxious consequences of single-use plastics affecting entire ecosystems. This study demonstrates a potential avenue of materials upcycling by studying the effects of coupling PET with the thermoplastic elastomer styrene-ethylene-butylene-styrene …

Thin Film Piezoelectric Energy Harvesting Nanostructured Materials: Tailoring Size, Porosity, Morphology Of Zinc Stannate Perovskites (Abx3), Christopher Munoz

Theses and Dissertations

Three dimensional (3D) piezoelectric zinc stannate (ZnSnO3) nanoweb arrays are synthesized using a combination of treatment methods deposited in PDMS thin films for electrochemical analysis of its piezoelectric response. Advantages of hydrothermal, molten salt, and solvothermal synthesis methods were leveraged to facilitate several chemical and surface engineering techniques. The combination of these treatments reduce the size of zinc stannate to approximately ~40nm-80nm weblike networks, much smaller than previously reported ZnSnO3 sub-micro cubes. Scanning electron microscopy (SEM) and X-Ray Diffraction (XRD) analysis reveal a mesoporous protonated tristannate (H2Sn3O7) nanoweb template with connecting wirelike strands having diameters ranging from 12-27nm across and …

Electrolysis Degradation Of Cyanuric Acid In Wastewater At Cu/Go Cathodes, Chioma Chinwe Nwakanobi

Theses and Dissertations

This work evaluates the development of electrochemical processes for the oxidative degradation of persistent organic chemicals in waste waters, specifically the oxidation of cyanuric acid in the presence of NaCl at Cu/GO cathodes and Ti anodes. The experiment used a graphene oxide doped copper mesh cathode to examine different concentrations of cyanuric acid (30 mg/L, 40 mg/L, and 50 mg/L) and various concentrations of NaCl electrolyte (0.007mol/L, 0.03mol/L, 0.07mol/L, 0.1mol/L, and 0.2mol/L). In addition, the effect of pH (2, 4, 6, and 8), and applied current (0.200A, 0.150A and 0.100A) were studied. The Cu/GO electrode played a central role in …

Publication Of Undergraduate Experiments, Development Of Additional X-Ray Crystallography Experiments, And Proof-Of-Concept Cyclopropanation Reactions, Alain Beauparlant

Electronic Theses and Dissertations

Single crystal X-ray crystallography instructional materials were developed using a variety of compounds including sugar, Epsom salt, pyrite, copper(II) acetate, and rhodium(II) acetate. Rhodium(II) acetate was reacted with a variety of functionalized benzonitriles, and when crystals were obtained, characterized using single crystal X-ray crystallography. Rhodium(II) acetate with adducts of 4-nitrobenzonitrile and 4-(dimethylamino)benzonitrile were also characterized using proton NMR spectroscopy and Fourier Transform Infrared Spectroscopy. Rhodium(II) acetate with adducts of 4-(dimethylamino)benzonitrile was used as a catalyst in a proof-ofconcept reaction to determine if it acts as a catalyst in cyclopropanation reactions. Further, the new rhodium(II) acetate dinitrile compounds were investigated to …

Synthesis Of Bacterial Glycerophospholipids For Biomembrane Model Studies: A Means To Advanced Biofuels, Felix Adulley

Electronic Theses and Dissertations

To reduce reliance on fossil fuels, sustainable biofuels are being pursued, especially advanced biofuels like 1-butanol that have higher energy content and greater compatibility with existing infrastructure than ethanol. A persistent challenge is the yield-limiting toxicity of biofuels and process solvents, such as tetrahydrofuran, to the microbes that ferment biomass into biofuel. The cell membrane is a focal point of toxicity, and understanding how it interacts with fuels and solvents is key to improving yield. Phospholipid bilayers are the core of biomembranes, and model biomembranes of defined composition provide the ideal platform for biophysical studies. To this end, glycerophospholipids characteristic …

Electrodeposition Studies Of Gold Nanoparticles And Alginate Hydrogel Films., Harikrishnan Nambiathan Nambiar

Electronic Theses and Dissertations

This dissertation investigates the electrochemical deposition (ECD) and electrophoretic deposition (EPD) processes involving citrate (cit)-stabilized Au nanoparticles (NPs) and calcium alginate (Ca-Alg-Au NP) hydrogel films. The first part of the dissertation investigates the influence of NP size, surface area (SA) coverage, and ligand stabilizers on the electrochemical growth of Au on Au NPs, aiming to enhance our understanding of the growth process during the nucleation and growth of metal NPs. The growth kinetics depend on Au NP size (4 nm > 15 nm > 50 nm) for a constant SA coverage, as determined by the overpotentials for ECD. The growth rate increases …

Computational Quantum Chemistry Studies Of The Stabilities Of Radical Adducts Formed During The Oxidation Of Melatonin Derivatives, James Horne

Electronic Theses and Dissertations

Melatonin is a natural antioxidant that has been investigated for properties as a potential spin trap to identify short-lived free radicals. Computational quantum chemistry studies have been performed for the oxidation of melatonin to N¹-acetyl-N²-formyl-5-methoxykynuramine. This research focused on modification of melatonin into derivatives and analyzing the change in total molecular energy from melatonin to its oxidation product, as well as the corresponding derivatives. Each of the molecular geometries were optimized at the DFT/B3LYP/6-31G(d), DFT/B3LYP/cc-pVXZ (X = D, T), HF/6-31G(d), HF/cc-PVXZ (X = D, T), MP2/6-31G(d), and MP2/cc-PVXZ (X = D, T) levels of theory. …

Development Of A Methodology For The Quantification Of Reaerosolization Of A Biological Contaminate Surrogate Particle From A Military Uniform Fabric, George Cooksey, Jeremy M. Slagley, Casey W. Cooper, Douglas Lewis, Alisha Helm

Faculty Publications

In a mass casualty medical evacuation after a bioaerosol (BA) dispersal event, a decontamination (DC) method is needed that can both decontaminate and prevent biological particle (BP) re-aerosolization (RA) of contaminated clothes. However, neither the efficacy of current DC methods nor the risk of BP RA is greatly explored in the existing literature. The goals of this study were to develop a repeatable method to quantify the RA of a biological contaminant off military uniform fabric swatches and to test the efficacy of one DC protocol (high-volume, low-pressure water) using 1 µm polystyrene latex (PSL) spheres as a surrogate. A …

Perovskite Oxide Derivatives For Enhanced Electrochemical Water Splitting And Pseudocapacitor Applications., Md. Sofiul Alom

Electronic Theses and Dissertations

The global energy landscape is at a crossroads, marked by surging demand, finite fossil fuel reserves, and escalating environmental concerns stemming from carbon emissions. To address these challenges and transition towards a sustainable energy future, this dissertation embarks on a multidisciplinary exploration of perovskite oxides and their derivatives as catalysts and materials for advanced electrochemical water splitting and pseudocapacitive energy storage. In the quest for efficient water splitting catalysts, a series of quasi-2D oxides, SrLaAl_1/2M_1/2O₄ (M = Mn, Fe, Co), was synthesized and systematically studied where the B-site comprised of both transition metals and main …

Scalable Solution Processing Of Niox Nanoparticles., Peter James Armstrong

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) are a promising alternative to silicon-based photovoltaics. However, PSCs face several challenges due to shortcomings in their stability, module efficiency, and scaled production. Although PSCs is still a young field of research, significant attention has been given to demonstrating power conversion efficiencies that are on par with traditional silicon. With that target reached, converting the laboratory demonstration into practical materials to increase access and abundance of solar energy are among the next large targets for the field. This comes with material challenges for perovskite and their companion charge transport layers (CTLs). Among the charge transport materials …

Analysis Of Triton Cg 110 Foaming Characteristics For Use As A Potential Fire Suppressant, Addison Cobb, Jeremy Cho

Undergraduate Research Symposium Lightning Talks

Background: Per-FluoroAlkyls (PFAs) are incredibly stable molecules which do not biodegrade. These chemicals have been linked with a series of health issues and environmental problems.

Problem: PFAs have been identified in most drinking water supplies in the United States. Large Amounts of this is due to Aqueous Fire-Fighting Foams (AFFF’s), which contain PFAs, seeping into the groundwater supply.

Solution: While little can be done about PFAs currently in groundwater supplies, replacing PFA-based AFFFs with newer Eco-AFFFs can halt AFFF contamination, and maintain firefighting suppression.

An Efficient And Chemoselective Method To Generate Arynes, Bryan Metze, Riley A. Roberts, Aleksandra Nilova, David R. Stuart

Chemistry Faculty Publications and Presentations

Arynes hold immense potential as reactive intermediates in organic synthesis as they engage in a diverse range of mechanistically distinct chemical reactions. However, the poor functional group compatibility of generating arynes or their precursors has stymied their widespread use. Here, we show that generating arynes by deprotonation of an arene and elimination of an “onium” leaving group is mild, efficient and broad in scope. This is achieved by using aryl(TMP)iodonium salts (TMP = 2,4,6-trimethoxyphenyl) as the aryne precursor and potassium phosphate as the base, and a range of arynophiles are compatible. Additionally, we have performed the first quantitative analysis of …

Aspects Of Stochastic Geometric Mechanics In Molecular Biophysics, David Frost

All Dissertations

In confocal single-molecule FRET experiments, the joint distribution of FRET efficiency and donor lifetime distribution can reveal underlying molecular conformational dynamics via deviation from their theoretical Forster relationship. This shift is referred to as a dynamic shift. In this study, we investigate the influence of the free energy landscape in protein conformational dynamics on the dynamic shift by simulation of the associated continuum reaction coordinate Langevin dynamics, yielding a deeper understanding of the dynamic and structural information in the joint FRET efficiency and donor lifetime distribution. We develop novel Langevin models for the dye linker dynamics, including rotational dynamics, based …

Studies On Electrochemical Hydrogen Isotope Separation, Liyanage Mayura Sankalpa Silva

All Dissertations

Graphene-integrated Proton Exchange Membrane (PEM) electrochemical cells have emerged as a novel area of scientific investigation in the realm of hydrogen isotope separation. Chemical Vapor Deposited (CVD) graphene has been especially useful due to its large-scale production capability for scaling-up purposes. The research described in this dissertation explores the role that inadvertent introduction of cations, notably ammonium and copper, during the CVD graphene transfer onto PEM substrates, such as Nafion, might play in affecting hydrogen ion transport and isotope separation in PEM electrochemical cells. An extensive review of existing literature exposed a gap concerning unintentional cation introductions during graphene transfer, …

Hydrothermal Synthesis Of First-Row Transition Metal Polyanions Towards The Design Of Frustrated Magnetic Materials, Megan Smart

All Dissertations

Novel modern materials are constantly being discovered as humanity seeks constantly better improvement to the optics and electronics around us, from lasers used in medical therapies to the magnets and supercomputing chips in our phones. Inorganic oxides commonly draw inspiration from naturally occurring minerals to template new discoveries through substitution of similarly behaving elements with the goal of inducing certain desired properties, such as ferroelectricity or creating the elusive quantum spin liquid. While many minerals are silicates, its periodic table neighbor germanium(IV) has a rich and under-explored crystal chemistry that could contain many new structures and magnetic materials. Another common …

Understanding The Interaction Of Environmental Contaminants With Polystyrene Nanoparticles And Dna Using Nuclear Magnetic Resonance Spectroscopy And Density Functional Theory, Saduni Arachchi

All Dissertations

The objective of the thesis is to study the effect of environmental pollutants on polystyrene nanoparticles and biomolecules. This is done in two different techniques, particularly NMR and density functional theory. In this thesis, we use a combination of 1H NMR, Saturation-Transfer Difference (STD) NMR and relaxation experiments to study the interactions, kinetics and dynamics of antibiotics with polystyrene nanoparticles. (PS NPs) Density functional theory (DFT) is used to study the binding of commonly used non-oxidative hair dyes to biomolecules (DNA and amino acids) and PS particles.

Mechanical Properties Of Natural Osmia Lignaria Silk And Recombinant Expression Of The Silk Proteins, Jackson Morley

Undergraduate Honors Capstone Projects

The use of petroleum-based plastic and the subsequent waste has led researchers to explore alternatives in the form of biopolymers. Spider silk and hagfish intermediate filaments show the potential to be advantageously utilized in textile and biomedical industries. Bee silk is a sparsely studied biopolymer that has shown potential to be added to these other impressive biopolymers. Osmia lignaria, is a solitary bee native to the western United States. Silk from these bees can be isolated while the larvae are spinning their silk. The silk from these bees has been mechanically tested for strength, stress, strain, and elasticity. Cocoon …

Stereochemical Engineering Yields A Multifunctional Peptide Macrocycle Inhibitor Of Akt2 By Fine-Tuning Macrocycle-Cell Membrane Interactions, Arundhati Nag, Amirhossein Mafi, Samir Das, Mary Beth Yu, Belen Alvarez-Villalonga, Soo-Kyung Kim, Yapeng Su, William A. Goddard, James R. Heath

Chemistry

Macrocycle peptides are promising constructs for imaging and inhibiting extracellular, and cell membrane proteins, but their use for targeting intracellular proteins is typically limited by poor cell penetration. We report the development of a cell-penetrant high-affinity peptide ligand targeted to the phosphorylated Ser474 epitope of the (active) Akt2 kinase. This peptide can function as an allosteric inhibitor, an immunoprecipitation reagent, and a live cell immunohistochemical staining reagent. Two cell penetrant stereoisomers were prepared and shown to exhibit similar target binding affinities and hydrophobic character but 2-3-fold different rates of cell penetration. Experimental and computational studies resolved that the ligands’ difference …

Computational Study About Noncovalent Bonding Systems Involving Halogen, Chalcogen And Pnicogen Bonds, Jia Lu

All Graduate Theses and Dissertations, Fall 2023 to Present

First terms used in this thesis are introduced and defined as follows. In the periodic table, the elements in the 17^th column are named halogen including fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). The elements in the 16^th column are named chalcogen including oxygen (O), sulfur (S), selenium (Se) and tellurium (Te). The elements in the 15^th column are named pnicogen including nitrogen (N), phosphorus (P), arsenic (As) and antimony (Sb).

After hydrogen bonds (B-H⋅⋅⋅B) are well studied and understood by scientists and researchers, halogen bonds (R-X⋅⋅⋅B) have drawn attention due to the similarities in …

Designing And Studying Redox-Active Molecules For Energy Storage And Desalination, Wenda Wu

All Graduate Theses and Dissertations, Fall 2023 to Present

Since the fast growth of the global population, energy scarcity has become a new threat to modern society. Those commonly seen resources like fossil, coal, and natural gas are nonrenewable energies, which cannot be replenished by human-scale time. In contrast, wind, solar, and hydropower are the three main renewable green energies under development with great efforts around the world. However, the intermittent character of these powers raises a new question: how to store them properly on large scales? By 2021, more than 90% of the electricity storage was taken by Lithium-ion batteries (LIBs). The usage of lithium brings concerns about …

Chemical Investigation Of Dichloromethane Extract Of Aloe Vera Peels: An Agricultural Waste, Nazmul Huda

Theses and Dissertations

Aloe barbadensis Miller, commonly called Aloe Vera, is a widely popular succulent plant species cultivated across subtropical regions worldwide from India to the Tex-Mex border. Besides its historical uses, Aloe juice has garnered attention as a potential remedy for various ailments, particularly in treating various skin conditions and facilitating wound recovery, including obesity, diabetes, hepatitis, Crohn's disease, and ulcerative colitis. Regrettably, the agricultural practice following sap extraction involves discarding Aloe vera peels, constituting agricultural waste. As part of our continuous research on extraction, isolation, separation, and spectral characterization of value-added chemicals present in waste botanicals herein, …

Interaction Of Technetium (Iv) With Dibutyl Phosphate In N-Dodecane, Jonathan George

UNLV Theses, Dissertations, Professional Papers, and Capstones

During the reprocessing of nuclear fuel, the degradation of tributylphosphate (TBP) occurs as a result of radiolytic and thermal processes. These processes lead to the formation of minor amounts of dibutyl phosphate (HDBP). However, the presence of DBP poses a challenge in the partitioning of uranium (U), plutonium (Pu), and technetium (Tc) due to its chelating effects. The chelation of these elements by HDBP can interfere with their intended separation and purification, thereby impacting the efficiency and effectiveness of the reprocessing process. In this study, X-ray Absorption Fine Structure (XAFS) spectroscopy is employed to investigate the speciation of Tc following …