Physical Sciences and Mathematics Commons^™

Extraction Of Neutron-Gamma Irradiated Diffusion Pump Oils, Cooper L. Tillman

All Theses

This work successfully demonstrates solvent extraction methods for separation of oil from the by-products when two commercially available vacuum pump oils were exposed to an intense neutron and gamma-ray radiation environment. Nuclear fusion power at a commercial scale has accelerated the need for radiation resistant vacuum technology, such as oil-based diffusion pumps. Polyphenyl ether and aromatic silicone oils were irradiated at the Rhode Island Nuclear Science Center (RINSC) up to MGy absorbed doses with neutron and gamma-ray radiation. Solvent extractions were performed using hexane and isopropanol to characterize the oil extraction as a function of total absorbed dose. The by-products …

Catalytic Hydrogenation Of Co2 In Water And Ionic Liquids Using Platinum On Carbon, Kristin Collins

Masters Theses & Specialist Projects

Platinum-on-carbon (Pt/C) is a commercially-available catalyst that has been used in the literature to benchmark the performance of catalysts produced using platinum/cobalt alloy nanoparticles. Initially, we intended to build upon this example by synthesizing shape-controlled platinum/cobalt alloy nanoparticles in ionic liquids and compare their ability to catalyze the hydrogenation of CO₂ to methanol against Pt/C as a benchmark, with the idea that ionic liquids may improve catalysis. However, we found that Pt/C was unable to catalyze the hydrogenation of CO₂ to methanol. In an attempt to track the source of this discrepancy, Pt/C was characterized using thermogravimetric analysis …

Di­Chlorido­Tetra­Kis­(3-Meth­­Oxy­Aniline)Nickel(Ii), Benjamin A. Mukda, Mark M. Turnbull

Chemistry

The reaction of nickel(II) chloride with 3-meth­oxy­aniline yielded di­chlorido­tetra­kis­(3-meth­oxy­aniline)nickel(II), [NiCl₂(C₇H₉NO)₄], as yellow crystals. The Ni^II ion is pseudo-octa­hedral with the chloride ions trans to each other. The four 3-meth­oxy­aniline ligands differ primarily due to different conformations about the Ni—N bond, which also affect the hydrogen bonding. Inter­molecular N—H⋯ Cl hydrogen bonds and short Cl⋯Cl contacts between mol­ecules link them into chains parallel to the b axis.

Phthalocyanine-Enabled Technologies For Water Treatment And Disinfection Strategies, Hooralain Bushnaq, Catherine Munro, Sisi Pu, Amir Razmjou, Masoumeh Zargar, Giovanni Palmisano, Srinivas Mettu, Ludovic F. Dumée

Research outputs 2022 to 2026

Water treatment and disinfection are critical factors in ensuring a safe and sustainable water supply. Phthalocyanines (Pcs), a class of versatile and robust organic compounds, have garnered significant attention for their application in various water treatment processes. This review paper offers a groundbreaking investigation of Pc-enabled technologies within the domain of water treatment applications. The core aim of this review is to meticulously analyze the chemical and optical properties of Pcs, elucidate their photosensitization mechanism and establish the crucial connection between their chemical structure and photodynamic efficacy. The various modes of Pcs application in water treatment processes - whether in …

Evaluation Of Electrochemical Corrosion, Electrodeposition, And Other Electroanalytical Methods As Investigative Forensic Techniques For Advancing Metal Substrate Analysis, Crystal C. Kitanovski

UNLV Theses, Dissertations, Professional Papers, and Capstones

Friction ridge skin, bearing unique patterns of epidermal ridges commonly known as fingerprints, has served as a crucial tool for identification since ancient times, with its utilization dating back to Chinese culture around 221 B.C. Today, friction ridge skin impressions remain vital evidence in forensic investigations, aiding in the identification of suspects. While fingerprints, palm prints, and footprints can all serve as identifying markers, this dissertation focuses specifically on fingerprints, broadly classified as visible or latent. Latent fingerprints, though invisible to the naked eye, constitute the majority of prints collected from crime scenes, necessitating physical, chemical, or physicochemical processing for …

Characterizing Gsk3Β Interaction And Kinetics Via Isothermal Titration Calorimetry, W A Bhagya De Silva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glycogen synthase kinase 3β (GSK3β) is a multifunctional serine/threonine kinase involved in several key signaling pathways, including glycogen metabolism, WNT/β-catenin, and Hedgehog signaling. Hyperactivity of GSK3β has been linked to Alzheimer’s disease, bipolar disorder, type II diabetes, and some cancers. Therefore, GSK3β is of interest as a target for therapeutics. Lithium ion (Li+) is a classical inhibitor of GSK3β. Structurally similar beryllium ion (Be2+) is ~1000-fold more potent. Lithium and beryllium have demonstrated pathway-specific and cell type-specific inhibition of GSK3β, prompting an investigation into the inhibitory mechanisms and thermodynamic characteristics of the metal-enzyme interaction.Isothermal titration calorimetry (ITC) is a label-free …

Evolution Mechanism Of Organic Macromolecular Structure During Lignite Pyrolysis, Ying Shi, Yanming Zhu, Zhenjiang You, Wu Li, Yang Wang, Yu Song

Research outputs 2022 to 2026

Understanding the mechanisms governing coal pyrolysis reactions, particularly in relation to the coal macromolecular structure, is crucial for improving energy efficiency and facilitating the transition of coal into a clean energy source. This study employs cutting-edge techniques, such as High-Resolution Transmission Electron Microscopy (HRTEM) and Thermogravimetric Analysis coupled with Fourier Transform Infrared Spectroscopy and Mass Spectrometry (TG–FTIR–MS), to analyze lignite and its residual solid samples subjected to pyrolysis across a range of temperatures from 300 °C to 1100 °C. The variational characteristics of the macromolecular structure during coal pyrolysis are examined. Utilizing molecular dynamics simulations, we analyze the evolution mechanism …

Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel

Chemistry and Chemical Biology ETDs

Organo-transition metal complexes are being widely studied to understand their photophysical properties for their wide range of applications as efficient emitters in organic light emitting diodes (OLEDs), light emitting electrochemical cells (LEECs), etc. Cyclometalated organo-transition metal complexes such as cyclometalated square planar platinum(II) complexes are becoming suitable candidates for such applications because of their highly efficient luminescence. Understanding the excited properties of such complexes is useful in designing highly efficient and color tunable phosphors with desired excited state lifetimes. We aim to explore the influence of radical substituents on electronic structure, luminescence quantum efficiencies, and excited state lifetimes by synthesizing …

We Think, We Smell, We Remember: The Effect Of Smell On Memory For Chemistry Lab Learning, Michael A. Marino, Francine Wisnewski, Catherine Reilly, Andre Alexis

Faculty Presentations: BCES

The traditional five senses are the primary receptors of external stimuli for the brain. While tactile learning and visual observations are integral to the chemistry laboratory, olfaction is a sense that should be considered part of an educator's repertoire. Previous studies have discovered that our sense of smell plays a significant role in triggering memories. Moreover, specific scents like vanillin can prompt anamneses to recall previous experiences. A sample of 61 college students was employed for a three-week pretest-posttest control group experimental design. In the first week, participants conducted a chemical reaction to synthesize isoamyl acetate, the familiar and nontoxic …

Professor Yong Yang, The Editorial Board Member Of Journal Of Electrochemistry, Is Elected As A Fellow Of The Electrochemical Society, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Kai Wu, The Editorial Board Member Of Journal Of Electrochemistry And Chief Scientist Of Catl, Receives The National Science And Technology Progress Award, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Series Reports (1/4): Advancements In Electrochemical Energy Conversions At Prof Wei’S Group Of Chongqing University: High-Performance Oxygen Reduction Catalysts For Fuel Cells, Fa-Dong Chen, Zhuo-Yang Xie, Meng-Ting Li, Si-Guo Chen, Wei Ding, Li Li, Jing Li, Zi-Dong Wei

Journal of Electrochemistry

Two major challenges, high cost and short lifespan, have been hindering the commercialization process of low-temperature fuel cells. Professor Wei’s group has been focusing on decreasing cathode Pt loadings without losses of activity and durability, and their research advances in this area over the past three decades are briefly reviewed herein. Regarding the Pt-based catalysts and the low Pt usage, they have firstly tried to clarify the degradation mechanism of Pt/C catalysts, and then demonstrated that the activity and stability could be improved by three strategies: regulating the nanostructures of the active sites, enhancing the effects of support materials, and …

First Announcement Of 76th Annual Meeting Of The International Society Of Electrochemistry, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry, Qiong Sun, Hai-Hui Du, Tian-Jiang Sun, Dian-Tao Li, Min Cheng, Jing Liang, Hai-Xia Li, Zhan-Liang Tao

Journal of Electrochemistry

The unstable zinc (Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries. Herein, the hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the interface chemistry. The strong interactions among sorbitol and both water molecules and Zn electrode can reduce the free water activity, optimize the solvation shell of water and Zn²⁺ ions, and regulate the formation of local water (H₂O)-poor environment on the surface of Zn electrode, which effectively inhibit the decomposition of water molecules, and thus, achieve the thermodynamically stable …

Data-Driven Viewpoint For Developing Next-Generation Mg-Ion Solid-State Electrolytes, Fang-Ling Yang, Ryuhei Sato, Eric Jian-Feng Cheng, Kazuaki Kisu, Qian Wang, Xue Jia, Shin-Ichi Orimo, Hao Li

Journal of Electrochemistry

Magnesium (Mg) is a promising alternative to lithium (Li) in solid-state batteries due to its abundance and high theoretical volumetric capacity. However, the sluggish Mg-ion conduction in the lattice of solid-state electrolytes (SSEs) is one of the key challenges that hamper the development of Mg-ion solid-state batteries. Though various Mg-ion SSEs have been reported in recent years, key insights are hard to be derived from a single literature report. Besides, the structure-performance relationships of Mg-ion SSEs need to be further unraveled to provide a more precise design guideline for SSEs. In this Viewpoints article, we analyze the structural characteristics of …

Freedom As The Physical Notion. Mechanics Of A Material Point, Michael Vigdorowitsch

Karbala International Journal of Modern Science

This is a novel conceptual attempt to introduce freedom as a consistent physical notion. The present consideration is limited to mechanics of a material point. Adapted to physical representation, freedom is tested throughout the paper to conform to its general perception. It is first tried on such physical notions (but not restricted to) as potency of a set, Lagrangian, action, degrees of freedom. Defined as angular and essentially nonlinear variable, it appears to be dual as that the domain affords and that the material point possesses within the domain, not necessarily equal to one another. Freedom has to degrade if …

Synthesis Of Portions Of An Acinetobacter Baumannii Lipooligosaccharide (Los), Brandon Conrad

LSU Doctoral Dissertations

Glycoconjugate vaccines have become an effective strategy for protection against an array of globally persistent diseases resulting from pathogenic bacteria such as Haemophilus influenzae type b (Hib), Neisseria meningitidis, and Salmonella enterica serotype Typhi. Comprised of a carbohydrate (referred to as glycan) covalently inked to a carrier protein, these vaccines can initiate adaptive immunity by inducing B and T cell responses once in the lymphatic system. This is particularly relevant for infants two years of age and younger whose immune systems are not fully developed. A continuously emerging threat in clinical settings, Acinetobacter baumannii is a Gram-negative bacterium …

The Potential Influence Of Immune Modulatory Molecules (Tgf-Βiii And Ctla-4) In Pathogenicity Of Pcos, Mustafa Riyadh Abdullah, Hazima Mossa Alabassi

Karbala International Journal of Modern Science

Polycystic ovary syndrome (PCOS) is characterised by chronic anovulation, hyperandrogenism, polycystic ovaries, and immunological dysregulation. Immune homeostasis and inflammation management require immune functions. T-regulatory cells (Tregs) regulate PCOS's immune system, inflammation, insulin resistance, ovarian function, and homeostasis. Transforming growth factor βIII (TGF-βIII) and Cytotoxic-T-lymphocyte-associated-protein-4 (CTLA-4) receptors on the surfaces of Treg cells are important for controlling the immune system. The study included 68 PCOS patients and 22 non-PCOS women controls aged 20–45. The waist-hip ratio (WHR) determines obesity. We evaluated serum levels and gene expression of TGF-βIII and CTLA-4 via ELISA and real-time PCR. Women with PCOS had significantly higher …

Enhanced Optoelectronics Performance Of Hybrid Self Power Photodetectors Go: Tio2- Ad / N-Si Heterojunctions, Mohammed J. Alsultani, Maysoon F. Alias

Karbala International Journal of Modern Science

A GO:TiO₂/n-Si heterostructure has been submerged in an anthocyanin dye solution that extracted from the red cabbage plant creates a high responsivity, self-powered UV, and visible photodetectors fabricated by the spray pyrolysis technique. The GO concentrations are varied, whereas TiO₂ is fixed. Thin films' structure, shape, and optical characteristics were examined using X-ray diffraction, field emission scanning electron microscopy, and UV-Vis spectrophotometers respectively. Island-like polycrystalline film powders with grain boundaries and granular shapes are created. Two direct energy gaps between 3.33-3.02 and 2.39-2.04 eV exist in all films. J-V characteristics were examined. The saturation current density (J …

Investigating The Effect Of Bentonite Clay Compaction Density On The Corrosion Of Copper Materials, Claire Samantha Tully

Electronic Thesis and Dissertation Repository

As per international consensus on the best practice for managing used nuclear fuel (UNF), the Nuclear Waste Management Organization (NWMO) plan to isolate and contain UNF within a multiple-barrier system, underground in a deep geological repository (DGR). In the proposed design, used fuel bundles will be sealed in copper-coated carbon steel used fuel containers (UFCs), encased in blocks of highly compacted bentonite clay, and emplaced ~500-800 m (depending on host rock geology) below ground. Any gaps between the rock walls and the compacted bentonite blocks will be filled with a bentonite gap fill material (GFM).

The compacted bentonite material serves …

Toxicity Of Waterpipe Tobacco Smoking: The Role Of Flavors, Sweeteners, Humectants, And Charcoal, Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Maciej L. Goniewicz, Eleanore G. Hansen, Noura O. Kassem, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Waterpipe tobacco (WPT) smoking is a public health concern, particularly among youth and young adults. The global spread of WPT use has surged since the introduction of pre-packaged flavored and sweetened WPT, which is widely marketed as a safer tobacco alternative. Besides flavorants and sugars, WPT additives include humectants, which enhance the moisture and sweetness of WPT, act as solvents for flavors, and impart smoothness to the smoke, thus increasing appeal to users. In the United States (U.S.), unlike cigarette tobacco flavoring (with the exception of menthol), there is no FDA product standard or policy in place prohibiting sales of …

Policy Overview (June, 2024)

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

News Flash

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

Precision Deuteration And Hydrofunctionalization Of Aryl Alkynes And Alkenes, Samantha E. Sloane

Dissertations (1934 -)

The similar nature of the hydrogen atom to its isotope, deuterium, allows for the simple exchange of hydrogen atoms for deuterium atoms in drug molecules to alter the absorption, distribution, metabolism, and excretion properties. Installing the deuterium functionality into a specific site in the molecule is essential. Selective hydrofunctionalization reactions of alkynes and alkenes using the highly reactive catalytic Cu–H species have been well developed, and synthetic organic chemistry methods to selectively incorporate one or two deuterium atoms into the benzylic site of organic compounds, a key metabolic position, are elusive. A Cu–H catalytic approach offers selectivity and reactivity to …

Activity: Students Find Conceptual Errors In Ai Output, Janie Brennan

Generative AI Teaching Activities

Instructor asks ChatGPT questions related to a key concept to find one where ChatGPT has conceptual errors. Ask students to find the errors and explain them.

Prediction Of Pfoa And Pfos Toxicity Through Log P And Number Of Carbon With Comptox And Machine Learning Tools, Ahmed Dashtey, Patrick Mormile, Sandra Pedre, Stephany Maure Valdaliso, Walter Z. Tang

Department of Civil and Environmental Engineering Faculty Publications

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are two major groups of PFAS will be subjected to the Maximal Contamination Concentration (MCL) of 4 ng/l in drinking water to be implemented by the U.S. EPA by 2025. How to accurately predict toxicity of PFAS with varied carbon chain length is important for treatment and sequential removal from drinking water. This study presents Quantitative Structure and Activity Relationship (QSAR) models developed through both linear regression and two order regression. Log P is compiled from reference and carbon content is counted as the molecule represented. Bioconcentration potential is predicted from CompTox.The …

Synthesis And Computational Studies Of Α- And Δ-Substituted Macrocyclic Europium And Ytterbium Complexes, Delainey Amara Winder

Dissertations and Theses

The uses of macrocyclic lanthanide complexes are vast, with many targeted MRI contrast agents at the forefront of the field. Many of these are ParaCEST agents, which require exchangeable protons accessible on the macrocycle and the slow exchange of coordinated water molecules. The substitution at both the α- and δ-carbon on the amide pendant arm of these macrocyclic lanthanide complexes can lock bulky groups on the δ-carbon to a pseudo-axial position. When the α- and δ-carbons have the same chirality, the bulky group will be pseudo-equatorial, and when the chirality is opposed, the bulky group will be pseudo-axial. By performing …

Exploring The Chemistry Of Bis(Azido)Phosphine Chalcogenides And The Pursuit Of Isolable Phosphinidene Chalcogenides, John Lortie

Electronic Thesis and Dissertation Repository

The study of low-coordinate species and the pursuit of interesting bonding motifs has revealed new reactivity modes for main-group compounds, akin to transition metals, in the past two decades. An underexplored class of two-coordinate phosphorus compound is a phosphinidene sulfide, which has yet to be isolated in the solid-state with an accompanying crystal structure. This dissertation explores strategies towards the synthesis and reactivity of low-coordinate phosphinidene chalcogenide species, and related compounds supported by strongly pi-donating or weakly pi-donating environments. While the primary synthetic targets remained elusive, significant discoveries were made towards new methods of preparing electron rich phosphines, and the …

Kinetic Characterization And Identification Of Key Active Site Residues Of The L-Aspartate N-Hydroxylase, Cree, Sydney B. Johnson, Hannah Valentino, Pablo Sobrado

Chemistry Faculty Research & Creative Works

CreE is a flavin-dependent monooxygenase (FMO) that catalyzes three sequential nitrogen oxidation reactions of L-aspartate to produce nitrosuccinate, contributing to the biosynthesis of the antimicrobial and antiproliferative nautral product, cremeomycin. This compound contains a highly reactive diazo functional group for which the reaction of CreE is essential to its formation. Nitro and diazo functional groups can serve as potent electrophiles, important in some challenging nucleophilic addition reactions. Formation of these reactive groups positions CreE as a promising candidate for biomedical and synthetic applications. Here, we present the catalytic mechanism of CreE and the identification of active site residues critical to …

Kinetic Characterization And Identification Of Key Active Site Residues Of The L-Aspartate N-Hydroxylase, Cree, Sydney B. Johnson, Hannah Valentino, Pablo Sobrado

Chemistry Faculty Research & Creative Works

CreE is a flavin-dependent monooxygenase (FMO) that catalyzes three sequential nitrogen oxidation reactions of L-aspartate to produce nitrosuccinate, contributing to the biosynthesis of the antimicrobial and antiproliferative natural product, cremeomycin. This compound contains a highly reactive diazo functional group for which the reaction of CreE is essential to its formation. Nitro and diazo functional groups can serve as potent electrophiles, important in some challenging nucleophilic addition reactions. Formation of these reactive groups positions CreE as a promising candidate for biomedical and synthetic applications. Here, we present the catalytic mechanism of CreE and the identification of active site residues critical to …