Physical Sciences and Mathematics Commons^™

High Resolution Intracavity Laser Absorption Spectroscopy Of Transition Metal-Containing Diatomic Molecules, Kristin Bales

Dissertations

Three transition metal-containing diatomic molecules have been studied using intracavity laser spectroscopy. Many of the transitions were recorded using a Fourier-transform spectrometer for detection, allowing collection at Doppler-limited resolution for the gas phase molecules. Several vibrational bands in two electronic transition systems of tantalum fluoride (TaF) have been analyzed, and new molecular constants provided. Transitions involving six electronic states of tungsten sulfide (WS) have been analyzed, with new and updated constants provided, including a deperturbation analysis of three vibrational bands in two of the states. Finally, a fresh perspective on two electronic states of tungsten oxide (WO) included a deperturbation …

Rhodium-Catalyzed Asymmetric Synthesis Of P-P And P-C Bonds, Sarah T. Chachula

Dartmouth College Ph.D Dissertations

Chapter 1: Synthesis, Structure, Dynamics, and Enantioface-Selective η3-Benzyl Coordination in the Chiral Rhodium Complexes Rh(diphos*)(η3-CH2Ph) Abstract: The rhodium benzyl complexes Rh(diphos*)(η3-CH2Ph) (1-14, diphos* = chiral bis(phosphine)) were prepared either by treatment of Rh(COD)(η3-CH2Ph) (15, COD = 1,5-cyclooctadiene) with diphos*, or from the reaction of [Rh(diphos*)(Cl)]2 (16- 20) with PhCH2MgCl. For C2-symmetric diphos*, observation of one set of NMR signals for complexes 1-12 suggested that the two diastereomers in which different 3-benzyl enantiofaces were coordinated to rhodium interconverted rapidly on the NMR time scale via suprafacial shifts; observation of five inequivalent aryl 1H NMR signals showed that antarafacial shifts were slow …

Synthesis Of Small Molecule Modulators Of Non-Traditional Drug Targets, Jamie Nunziata

USF Tampa Graduate Theses and Dissertations

This work details the effort toward structure-activity-relationship (SAR) studies and synthesis of the small molecule modulators of two non-traditional drug targets. The first part of this manuscript (chapters 1–2) will discuss the collaborative work and synthesis of an inhibitor of Slingshot Homology 1 (SSH1) with the potential therapeutic application toward Alzheimer’s Disease (AD) treatment. The second part (chapters 3–6) will discuss the synthetic efforts toward modulation of a protein target known as STING, or stimulator of interferon genes, with the therapeutic application toward autoimmune disease or anti-tumor activity.

AD is a progressive and degenerative illness that holds the title of …

From Waste To Energy: The Electrochemical Reduction Of Co2 Using Recycled Nanostructured Catalysts, Ibrahim Badawy

Theses and Dissertations

The reduction of carbon dioxide (CO₂RR) using electrochemistry is a promising solution for the burgeoning global energy crisis. The overall vision of its implementation relies on renewable energy sources to power the reaction creating carbon neutral products and effectively closing the carbon cycle. Research in this field has come a long way since its inception in the mid-1900s. However, there remain significant hurdles and important considerations to overcome in order to reach full commercialization. Most electrocatalysts tested for CO₂RR have been designed solely for maximum performance while ignoring the environmental consequences if such a material were …

Photophysical Properties Of Synthetic Oligomeric Phenylene Ethynylene, Hugh F. Fritz Jr.

Chemistry and Chemical Biology ETDs

Oligomeric Phenylene Ethynylenes (OPEs) are a class of synthetically prepared compounds with the basic structure of phenylene rings connected by triple-bonded carbon atoms, also known as an ethyne link. This structure can be modified by incorporating functional groups onto one or more of the phenylene rings. The addition of functional groups, such as sulfoxide or imidazole, may alter the photophysical properties in detectable ways. The photophysical techniques used in this report include fluorescence, spectroscopy in the ultraviolet and visible light range (UVVIS), and photon-based excitation using a photo chamber.

One attractive function of OPEs is their antimicrobial property. Previously published …

Temperature-Pressure Phase Diagram Of Confined Monolayer Water/Ice At First-Principles Accuracy With A Machine-Learning Force Field, Bo Lin, Jian Jiang, Xiao Cheng Zeng, Lei Li

Chemistry Department: Faculty Publications

Understanding the phase behaviour of nanoconfined water films is of fundamental importance in broad fields of science and engineering. However, the phase behaviour of the thinnest water film – monolayer water – is still incompletely known. Here, we developed a machine-learning force field (MLFF) at first-principles accuracy to determine the phase diagram of monolayer water/ice in nanoconfinement with hydrophobic walls. We observed the spontaneous formation of two previously unreported high-density ices, namely, zigzag quasi-bilayer ice (ZZ-qBI) and branched-zigzag quasi-bilayer ice (bZZ-qBI). Unlike conventional bilayer ices, few inter-layer hydrogen bonds were observed in both quasi-bilayer ices. Notably, the bZZ-qBI entails a …

Confirmation Of N-Hexane As An Inert Co-Solvent In The Production Of Functionalized Silicon Nanoparticles From Reactive High-Energy Ball Milling, Julie P. Vanegas, Amanda Reusch, Mark J. Fink, Brian S. Mitchell

Chemistry Faculty Publications and Presentations

Alkanes such as n-hexane have been used as co-solvents in the production of functionalized semiconductor nanoparticles from alkenes and alkynes using Reactive High Energy Ball Milling (RHEBM) under the assumption that they are non-reactive under typical milling conditions. In this paper, we report on a comparative study with two hydrocarbon solvents of comparable chain length, 1-hexyne, and n-hexane, and their milling products using three different commercially available silicon precursors, namely single crystal silicon wafers and polycrystalline particles having a nominal size of 4 μm and 1 mm. We found that nanoparticle formation and surface functionalization in all the three silicon …

Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos

Chemistry Faculty Research & Creative Works

The tripodal compounds [(TMG₃trphen)M^II-solv](PF₆)₂ (M = Mn, Fe, Co; solv = MeCN, DMF) and bipodal analogues [(TMG₂biphen)M^II(NCMe)_x](PF₆)₂ (x = 3 for Mn, Fe; x = 2 for Co) and [(TMG₂biphen)M^IICl₂] have been synthesized with ligands that feature a triaryl- or diarylmethyl-amine framework and superbasic tetramethylguanidinyl residues (TMG). The dicationic M(II) sites mediate catalytic nitrene-transfer reactions between the imidoiodinane PhI═NTs (Ts = tosyl) and a panel of styrenes in MeCN to afford aziridines and low yields of imidazolines (upon …

Identification Of Unsuccessful Students In General Chemistry, G. Robert Shelton, Joseph M. Simpson, Diana Mason

All Faculty Scholarship

The Networking for Science Advancement (NSA) team collected data from multiple general chemistry courses at nine universities within a broad geographic setting in a majority-minority US state. Data include diagnostic scores on the Math-Up Skills Test (MUST), quantitative literacy/quantitative reasoning (QL/QR) quiz, along with student demographics, and overall course grades. From these data the team determined how automaticity skills in procedural arithmetic and quantitative literacy and reasoning can be used to predict success in lower-division chemistry courses. By expanding this dataset, we extended our investigations to discover what characterizes successful and unsuccessful students in general chemistry, first and second semesters …

The Effect Of Heat Treatment And Chemical Treatment On Natural Fibre To The Durability Of Wood Plastic Composites – A Review, Nuratiqah Asyiqin Mohd Nasharudin, Nur Fatihah Sulaiman, Nurul Aziemah Mohammad, Wan Nor Raihan Wan Jaafar, Falah Abu Dr., Siti Norasmah Surip

Journal of Materials Exploration and Findings

The application of WPC is not only limited to indoor applications but has been extended to exterior applications where properties of WPC could compromise during service life. WPC was derived from wood fiber of various sizes to reinforce polymers. Wood fiber has the advantage of a cheaper price, being abundantly available, and ease of processing, however, the critical factor is its hydrophilic nature, where moisture absorption is likely to occur. Thus, treatments for reducing the hydrophilicity of wood fibers are applied. By treatment of wood fiber, the surface impurities were removed, leaving the roughened surface of fibers, thus providing a …

Predictability Of The Must (Math-Up Skills Test), Diana Mason, G. Robert Shelton

All Faculty Scholarship

In the USA for the most part, completion of a first-semester general chemistry (Chem I) course lays the foundation deemed necessary for understanding second-semester general chemistry (Chem II) topics. Successful completion of Chem I and II gives students permission to progress to organic chemistry I (O-Chem). A series of studies undertaken by the NSA (Networking for Science Advancement) Texas team began in 2016. Texas is one of five majority-minority states in the USA and hosts a significant Hispanic population. The purpose of this research line is to evaluate the influence of basic arithmetic automaticity (what students can do without a …

Biological Formation Of Ethylene, Robert P. Hausinger, Simahudeen Bathir Jaber Sathik Rifayee, Midhun George Thomas, Shramana Chatterjee, Jian Hu, Christo Christov

Michigan Tech Publications, Part 2

This review summarizes the structures, biochemical properties, and mechanisms of two major biological sources of ethylene, the ethylene-forming enzyme (EFE) and 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACCO). EFE is found in selected bacteria and fungi where it catalyzes two reactions: (1) the oxygen-dependent conversion of 2-oxoglutarate (2OG) to ethylene plus three molecules of CO2/bicarbonate and (2) the oxidative decarboxylation of 2OG while transforming l-arginine to guanidine and l-Δ1-pyrroline-5-carboxylic acid. ACCO is present in plants where it makes the plant hormone by transforming ACC, O2, and an external reductant to ethylene, HCN, CO2, and water. Despite catalyzing distinct chemical reactions, EFE and …

Study On The Self-Repairing Effect Of Nanoclay In Powder Coatings For Corrosion Protection, Marshall S. Yang, Jinbao Huang, Hui Zhhang, James Noel, Yolanda S. Hedberg, Jian Chen, Ubong Eduok, Ivan Barker, Jeffrey D. Henderson, Chengqian Xian, Haiping Zhang, Jesse Zhu

Chemistry Publications

Powder coatings are a promising, solvent-free alternative to traditional liquid coatings due to the superior corrosion protection they provide. This study investigates the effects of incorporating montmorillonite-based nanoclay additives with different particle sizes into polyester/triglycidyl isocyanurate (polyester/TGIC) powder coatings. The objective is to enhance the corrosion-protective function of the coatings while addressing the limitations of commonly employed epoxy-based coating systems that exhibit inferior UV resistance. The anti-corrosive and surface qualities of the coatings were evaluated via neutral salt spray tests, electrochemical measurements, and surface analytical techniques. Results show that the nanoclay with a larger particle size of 18.38 µm (D50, …

Investigating The Effects Of The Sugar Alcohol Osmolytes Glycerol And Erythritol In Aot Reverse Micelles, Animesh Dali '24, Bridget Gourley

Student Research

Water is a polar molecule that participates in hydrogen bonding and proton transfer. Geometric confinement and water’s interactions with osmolytes (small water soluble compounds) affect the ability of water molecules to hydrogen bond and transfer charges. Study of this behaviour of water with different osmolytes in controlled environments will help us develop predictive models. In our study, we have prepared Sodium bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelles (RM) in 2,2,4-Trimethylpentane (Isooctane). Our principle osmolytes were the straight chain sugar alcohols glycerol and erythritol. Study of water-osmolyte behaviour in the small and confined pool of a reverse micelle allows us examine the difference …

Strong Ultrafast Demagnetization Due To The Intraband Transitions, G.P. Zhang

University Honors Program

No abstract provided.

Understanding Mitochondrial Dysfunction In Neurodegenerative Diseases Using Novel Neuron Cell Models, Amy Apfelbaum, Anthony Grillo Phd, Raghav Dutta Phd, Alaa Hassan

Annual Student Research Poster Session

This past summer I worked Dr. Anthony Grillo’s lab under my mentors Raghav Dutta and Alaa Hassan at the University of Cincinnati. The Grillo Lab is focused on understanding the mechanisms of mitochondrial complex 1 dysfunction in neurodegenerative diseases. It has been shown that an early feature of neurodegeneration is complex 1 dysfunction; we were trying to determine if this is a cause or an effect of these diseases. This summer, we focused on identifying different types of neuron subtypes in brain tissue samples, isolating primary neurons by first identifying and visualizing the types of brain cells present in brain …

Amyloid-Beta Protein Concentration Dependence Of Reversible Aggregation Using Gold Colloid Particles, Renee Spencer, Lila Kocieniewski, Bryan Martinez, Kazushige Yokoyama

McNair Scholars Program

Although Alzheimer’s and COVID-19 are different diseases, the commonality between them is during the process of them developing in a person by fibrillogenesis. The product of fibrillogenesis results in the development of these diseases. We study the first stage of fibrillogenesis where the amyloid-beta peptide monomers are assembled into an oligomer. We want to isolate this oligomer using gold colloids because this step can be reversed. Utilizing gold colloids allows us to freeze fibrillogenesis in the first step by folding and unfolding the protein repeatedly through a series of pH changes from 4 or below to 10 or higher. At …

Investigation Of Vitamin D Metabolites Using Different Ion Mobility-Mass Spectrometry (Im-Ms) Methods, Selena Kingsley, Christopher D. Chouinard

Chemistry Summer Research Program

No abstract provided.

The Dynamic Shift To Green Chemistry: Investigating The Spectral Behavior Of Natural Deep Eutectic Solvents (Nades) And Their Performance As Maldi-Tof Matrices, Grayson Weavil, Lucas B. Ayres, Miguel Jose-Bueno, Rakesh Sachdeva, Carlos D. Garcia

Chemistry Summer Research Program

No abstract provided.

Investigation Of Vitamin D Metabolites Using Different Ion Mobility-Mass Spectrometry (Im-Ms) Methods, Selena Kingsley, Christopher D. Chouinard

Chemistry Summer Research Program

No abstract provided.

Prediction Of Dislocation Densities In Pure Metals And Alloys, J. Garey Weaver, Enrique Martinez

Chemistry Summer Research Program

No abstract provided.

Measurement Of Protein And Drug Adsorption On Nanoparticles By Competition With Dyes, Ashleigh Carroll, Jason Mcneill

Chemistry Summer Research Program

No abstract provided.

Development Of A Rapid Sars-Cov-2 Nucleocapsid Assay Using Buoyant And Magnetic (Bam) Beads, Spasenija Radenovic, Zahra Karimpourkalou, Chaunlei Wang, Jeffrey N. Anker

Chemistry Summer Research Program

No abstract provided.

Isolation Of Bovine Milk-Derived Exosomes Via A Polyester Capillary- Channeled Polymer (C-Cp) Fiber Stationary Phase, Jerisa Pimentel, Carolina Mata, R. Kenneth Marcus

Chemistry Summer Research Program

No abstract provided.

Multi-Catalysis: Trifluoromethylation Of Amides, Ethan Apsley, Jason Wilt, Giovani Gutierrez, Byoungmoo Kim

Chemistry Summer Research Program

No abstract provided.

Cadmium And Salinity Stressor Antagonism On Vallisneria Neotropicalis, Christopher P. Mikolaitis

<strong> Theses and Dissertations </strong>

Submerged macrophytes form the foundation of freshwater ecosystems. These organisms are sessile and are very susceptible to shifts in their environment. Heavy metals are of particular concern as they can be sequestered indefinitely in sediments and are readily taken up by rooted vegetation. In the presence of saltwater intrusions, these metals can interact with salt ions potentially changing their availability to submerged vegetation. In this study a freshwater macrophyte, Vallisneria neotropicalis, was used as a test species for interactive effects between Cd, a non-essential heavy metal, and salt stress. The metrics used to establish the individual as well as …

Photophysical And Photocatalytic Properties Of Covalent Organic Frameworks, Daniel Streater H.

Dissertations (1934 -)

This dissertation is most interested in how a class of materials known as covalent organic frameworks (COFs) can be designed to capture photon energy to initiate chemical reactions. Different COF designs change how long the energy is held, how it migrates, and how it is dispersed – and these differences can be used to change their performance as artificial photosynthesis platforms. Thus, it is helpful to have an informative discussion about the processes behind natural photosynthesis, that is, nature’s light harvesting strategies and photocatalytic schemes (Section 1.2) and will lead into an introduction of COFs and why they possess unique …

Scope And Mechanistic Studies Of Ruthenium Catalyzed C-C And C-N Bond Activation Reactions, Dulanjali Thennakoon

Dissertations (1934 -)

Transition metal catalyzed selective C–C and C–N bond activation reactions emerged as an effective synthetic tool in organic chemistry. Reorganization of these bond connections allows access to complex molecular scaffolds from readily available starting materials which are immensely useful for organic synthesis of pharmaceutical agents. While enormous progress has been achieved to date, major challenges still remain in desigining broad applicable catalytic bond activation methods. The well-defined cationic Ru–H complex with a benzoquinone ligand was found to be an effective catalytic system for the deaminative coupling reaction of enones with amines which enable regioselective cleavage of unstrained Cα–Cβ bond of …

Identification Of The Autoregulatory Properties And Molecular Interactions Of The Lysine-Specific Histone Demethylase 1 Enzyme, Dulmi Senanayaka

Dissertations (1934 -)

The conserved chromatin-remodeling enzyme, Lysine-Specific histone1/2 Demethylase 1 (LSD1) primarily demethylates Histone H3K4me , acting as a transcriptional repressor. It plays pivotal roles in various physiological processes including cancer and interacts with many regulatory proteins, non-coding RNAs, and small metabolites. However, little biochemical information is known about LSD1’s N-terminal intrinsically disordered region (IDR) and how LSD1 interacts with various biomolecules in the context of nucleosome. I present evidence that the IDR of LSD1, containing multiple post translational modifications (PTMs) and a nuclear localization signal (NLS), can act as a reversible competitive autoinhibitor of LSD1’s activity. This autoinhibition can be relieved …

Nuclear Magnetic Resonance Studies Of Potential Environmental Contaminants Interacting With Dna, Anna Hopkins, Leah B. Casabianca

Chemistry Summer Research Program

No abstract provided.