Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes,
2024
The University of Texas Rio Grande Valley
Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin
Research Symposium
Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations to elucidate Pt(0)-mediated C–CP bond activation mechanisms in phosphaalkynes. Investigating the …
Embedding Information Literacy Practices In An Upper Division Chemistry Lab Class At A University In The United States Of America,
2024
University of Central Florida
Embedding Information Literacy Practices In An Upper Division Chemistry Lab Class At A University In The United States Of America, Christopher Randles, Matilynn Lamm, Katy A. Miller
Faculty Scholarship and Creative Works
This poster discusses the implementation of information literacy into an upper division inorganic chemistry lab and the strategies employed to develop students’ information literacy in the laboratory course.
Reversible O–H Bond Activation By Tripodal Tris(Nitroxide) Aluminum And Gallium Complexes,
2024
Swarthmore College
Reversible O–H Bond Activation By Tripodal Tris(Nitroxide) Aluminum And Gallium Complexes, Joseph S. Scott , '22, Mika L. Maenaga , '21, Audra J. Woodside , '19, Vivian W. Guo , '26, Alex R. Cheriel , '24, M. R. Gau, Paul R. Rablen, Christopher R. Graves
Chemistry & Biochemistry Faculty Works
Herein, we report the preparation and characterization of the Group 13 metal complexes of a tripodal tris(nitroxide)-based ligand, designated (TriNOx³⁻)M (M = Al (1), Ga (2), In (3)). Complexes 1 and 2 both activate the O–H bond of a range of alcohols spanning a ∼10 pKₐ unit range via an element-ligand cooperative pathway to afford the zwitterionic complexes (HTriNOx²⁻)M–OR. Structures of these alcohol adduct products are discussed. We demonstrate that the thermodynamic and kinetic aspects of the reactions are both influenced by the identity of the metal, with 1 having higher reaction equilibrium constants and proceeding at a …
Auto-Combustion Synthesis Of Lanthanum-Doped Tio2 Nanostructures For Efficient Photocatalytic Degradation Of Crystal Violet Dye,
2024
The British University in Egypt
Auto-Combustion Synthesis Of Lanthanum-Doped Tio2 Nanostructures For Efficient Photocatalytic Degradation Of Crystal Violet Dye, Gharieb Meselhy, Mostafa Yasine Nassar, Ibrahim Mohamed Nassar, Sabry Hamed Seda
Dentistry
Utilising the solution combustion technique, nanocrystalline photocatalysts that included both pristine TiO2 and doped TiO2 with various La (III) dopant percentages (1, 3, 5, and 7 mol%) were created. Different methods, including thermal analysis, high-resolution transmission electron microscopy (HR-TEM), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), and field-emission scanning electron microscopy (FE-SEM), were used to investigate the prepared nanostructures. The XRD results indicated the anatase form and the crystalline nature of the products (pristine and doped TiO2) in the size range of a crystallite (5–16.5) nm. The photocatalytic assessment of the prepared nano-photocatalysts was carried out by …
Effect Of Zwitterionic Additives On Solvation And Transport Of Sodium And Potassium Cations In (Ethylene Oxide)10: A Molecular Dynamics Simulation Study,
2024
University of Kentucky
Effect Of Zwitterionic Additives On Solvation And Transport Of Sodium And Potassium Cations In (Ethylene Oxide)10: A Molecular Dynamics Simulation Study, Manh Tien Nguyen, Yuhua Duan, Qing Shao
Markey Cancer Center Faculty Publications
Sodium- (Na+) and potassium- (K+) ion batteries are cost-effective alternatives to lithium- ion (Li+) batteries due to the abundant sodium and potassium resources. Solid polymer electrolytes (SPEs) are essential for safer and more efficient Na+ and K+ batteries because they often exhibit low ionic conductivity at room temperature. While zwitterionic (ZW) materials enhance Li+ battery conductivity, their potential for Na+ and K+ transport in batteries remains unexplored. In this study, we investigated the effect of three ZW molecules (ChoPO4, i.e., 2-methacryloyloxyethyl phosphoryl- choline, ImSO3, i.e., sulfobetaine ethylimidazole, and ImCO2, i.e., carboxybetaine ethylimidazole) on the dissociation of Na+ and K+ coordination …
On Water Arrangements In Right- And Left-Handed Dna Structures,
2024
Swarthmore College
On Water Arrangements In Right- And Left-Handed Dna Structures, Liliya A. Yatsunyk, S. Neidle
Chemistry & Biochemistry Faculty Works
DNA requires hydration to maintain its structural integrity. Crystallographic analyses have enabled patterns of water arrangements to be visualized. We survey these water motifs in this review, focusing on left- and right-handed duplex and quadruplex DNAs, together with the i-motif. Common patterns of linear spines of water organization in grooves have been identified and are widely prevalent in right-handed duplexes and quadruplexes. By contrast, a left-handed quadruplex has a distinctive wheel of hydration populating the almost completely circular single groove in this structure.
Thermosensitive Phosphors As Optical Temperature Sensors In Extreme Environments,
2024
Wayne State University
Thermosensitive Phosphors As Optical Temperature Sensors In Extreme Environments, Marcos Ramon Imer Rocha Pita
Wayne State University Dissertations
Luminescent temperature sensors offer unique advantages over thermocouples and pyrometers for applications in extreme environments such as operando wall temperature mapping of combustion engines. A refractory oxide host doped with an optically active ion has the potential to afford a thermosensitive phosphor with a well-defined temperature response in such extreme environments. However, the design of thermosensitive phosphors with targeted temperature sensitivity and spatial resolution in the operational temperature range of interest has been hindered by the inability to rationally select host–activator pairs. A major scientific question is what crystal-chemistry features a low thermal conductivity oxide must possess to afford a …
Solution Combustion Synthesis And Characterization Of Fumarolic Mineral Dolerophanite, Copper (Ii) Oxide Sulfate,
2024
University of Texas at Arlington
Solution Combustion Synthesis And Characterization Of Fumarolic Mineral Dolerophanite, Copper (Ii) Oxide Sulfate, Eric J. Cyganowski
Chemistry & Biochemistry Theses - Archive
Dolerophanite Cu2OSO4 is a rare mineral found almost exclusively in the fumaroles of volcano systems and is sensitive to temperature and humidity conditions. It has a monoclinic C2/m crystal structure characterized by two-dimensional layers composed of sulfate anions dispersed amongst copper (II) oxide backbones. There has been recent interest in dolerophanite due to the magnetic properties of its Kagome-like lattice as well as its potential use as a photocatalyst or Li-ion battery electrode. Literature on the material however has been limited by the available synthesis strategies. As such, this thesis work presents a novel strategy …
Elucidation Of The Optical Properties Of Si And Si-Ge Alloy Nanostructures With Visible To Near-Ir Photoluminescence,
2024
Virgnia Commonwealth University
Elucidation Of The Optical Properties Of Si And Si-Ge Alloy Nanostructures With Visible To Near-Ir Photoluminescence, Griffin Spence
Theses and Dissertations
Silicon and silicon-germanium alloy nanostructures have garnered increasing attention in the past 25 years due to their favorable optical properties, visible to near-IR luminescence, and inherently low toxicity. While many synthetic routes have been discussed in the literature, the high-temperature, solid-state disproportionation of hydrogen silsesquioxane (HSQ) has become the most popular way to produce highly crystalline, size-tunable Si and Si-based nanostructures (NCs). It has been shown in this work that maximum annealing temperature from 450°-1100°C and the addition of GeI2or SnCl4 precursors can be used to achieve different morphologies, alloying efficiency, and sizes. Directly annealing HSQ from …
Amination Of 2-Bromo-6-Methylaminopyridine,
2024
Georgia Southern University
Amination Of 2-Bromo-6-Methylaminopyridine, Matthew H. Elterman
Honors College Theses
Extended metal atom chains (EMACs) represent molecular structures comprising a linear arrangement of metal ions, accompanied by supporting ligands. These compounds possess intriguing properties, yet remain understudied, drawing interest from diverse fields such as physics. However, synthesizing these multimetallic complexes poses significant challenges due to their intricate nature and specificity. Bridging ligands like silyl aminopyridine (SAP) and dipyridyl amine (DAP) have been utilized successfully to support EMACs, with SAP's application in this context being limited to a single published case, highlighting the urgent need for stabilization. This project aims to address this challenge through the synthesis of a novel scaffolded …
Synthesis, Characterization, And Reactivity Studies Of Pyridine Dipyrrolide Iron-Carbene Complexes With Electronically Distinct Carbene Moieties,
2024
West Virginia University
Synthesis, Characterization, And Reactivity Studies Of Pyridine Dipyrrolide Iron-Carbene Complexes With Electronically Distinct Carbene Moieties, Jose G. Rodriguez
Graduate Theses, Dissertations, and Problem Reports (ETD)
First, three (MesPDPPh) iron carbene complexes with electronically distinct carbene moieties were synthesized. These transitional iron carbene complexes were first characterized by 1H nuclear magnetic resonance (NMR) spectroscopy as their spectra showed paramagnetically shifted resonances. Additionally, their respected solid state structures were collected via X-ray diffraction. The two donor/acceptor iron carbene complexes [(MesPDPPh)Fe(C(CO2Me)(4-FPh) and (MesPDPPh)Fe(C(CO2Me)(4-MeOPh)] demonstrated a weak Fe-O interaction between the iron center and ester function group while the (MesPDPPh)Fe(IMe) displayed a C2v symmetric structure in the …
A Facile Auto-Combustion Pathway For Creating Mn- And Fe-Doped Tio2 Nanostructures And Their Photocatalytic Activity,
2024
The British University in Egypt
A Facile Auto-Combustion Pathway For Creating Mn- And Fe-Doped Tio2 Nanostructures And Their Photocatalytic Activity, Gharieb Meselhy
Dentistry
Using a combination of two fuels, an auto-combustion method was used to synthesize pure TiO2 and doped TiO2 with different concentrations of iron(III) (Fe) and manganese(II) (Mn) (1, 3, 5, and 7 mol%). The as-prepared materials were characterized using different techniques, including thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM). The XRD results showed that both pure TiO2 and all doped TiO2 samples had the anatase phase, indicating the crystalline nature of all the as-prepared nanomaterials. Crystal violet decolorization under UV irradiation was used to …
Mechanisms Of Dendritic Shorting In Lithium Metal Batteries With Li7la3zr2o12 Solid Electrolytes,
2024
Claremont Colleges
Mechanisms Of Dendritic Shorting In Lithium Metal Batteries With Li7la3zr2o12 Solid Electrolytes, Lukas Karapin-Springorum
Pomona Senior Theses
Energy storage will play a crucial role in efforts to mitigate the effects of climate change caused by greenhouse gas emissions from human activity. Lithium metal batteries using solid electrolytes like Li7La3Zr2O12 have higher energy density than lithium-ion batteries, which may enable a more rapid and complete electrification of transportation. However, lithium metal batteries suffer from undesirable short-circuiting when metallic lithium deposits connect the two electrodes. It has been debated whether these lithium dendrites generally grow directionally from the anode or are generated by the reduction of lithium ions inside the solid electrolyte, …
A Comparative Study Of Cationic Copper(I) Reagents Supported By Bipodal Tetramethylguanidinyl-Containing Ligands As Nitrene-Transfer Catalysts,
2024
Missouri University of Science and Technology
A Comparative Study Of Cationic Copper(I) Reagents Supported By Bipodal Tetramethylguanidinyl-Containing Ligands As Nitrene-Transfer Catalysts, Suraj Kumar Sahoo, Brent Harfmann, Himanshu Bhatia, Harish Singh, Srikanth Balijapelly, Amitava Choudhury, Pericles Stavropoulos
Chemistry Faculty Research & Creative Works
The Bipodal Compounds [(TMG2biphenN-R)CuI-NCMe](PF6) (R = Me, Ar (4-CF3Ph-)) And [(TMG2biphenN-Me)CuI-I] Have Been Synthesized With Ligands That Feature A Diarylmethyl- And Triaryl-Amine Framework And Superbasic Tetramethylguanidinyl Residues (TMG). The Cationic Cu(I) Sites Mediate Catalytic Nitrene-Transfer Reactions Between The Imidoiodinane PhI = NTs (Ts = Tosyl) And A Panel Of Styrenes In MeCN, To Afford Aziridines, Demonstrating Comparable Reactivity Profiles. The Copper Reagents Have Been Further Explored To Execute C-H Amination Reactions With A Variety Of Aliphatic And Aromatic Hydrocarbons And Two Distinct Nitrene Sources PhI = NTs And PhI = NTces (Tces = 2,2,2-Trichloroethylsulfamate) In Benzene/HFIP (10:2 V/v). Good Yields …
Introducing Ordered Silicon Vacancies Into Wsi2,
2024
Missouri State University
Introducing Ordered Silicon Vacancies Into Wsi2, Grace M. Atkins
Graduate Theses/Dissertations
Thermoelectric materials are very useful in industry due to their unique ability to convert waste heat into electricity. One such reported thermoelectric material is rhenium silicide (ReSi1.75▯0.25), resulting from ordered silicon vacancies in its crystal structure. The purpose of this project is to dope tungsten silicide (WSi2) with more electron rich elements to find a ternary silicide with a similar crystal structure to ReSi1.75▯0.25, in order to synthesize a less expensive thermoelectric material. Two synthesis methods are used in this project to dope WSi2. Powder x-ray diffraction (XRD) …
Compton Scattering Of Mammographic Soft X-Ray Beams By Alkali And Transition Metal Salt Filters Produce X-Ray Interference Zones That May Have Treatment Potential For Localized Cancer Lesions,
2024
CUNY New York City College of Technology
Compton Scattering Of Mammographic Soft X-Ray Beams By Alkali And Transition Metal Salt Filters Produce X-Ray Interference Zones That May Have Treatment Potential For Localized Cancer Lesions, Subhendra N. Sarkar, Eric Lobel, Sabina Rakhmatova, Derbie Desir, Somdat Kissoon, Daler Djuraev, Katie Tam
Publications and Research
In breast x-ray imaging scattered radiation adds 50% of harmful radiation dose from anisotropic Compton scattering mechanism. We have been working with double layered inorganic salt materials that can induce Compton scattering to the incident mammographic x ray beams (in 20-30 kVp range) with adequate isotropy (angular control). Typically metal nitrates and alkali halide salt layers are shown here to cause low energy radiation interference zones with high and low photon intensities and local flux heterogeneity in terms of flux covariance. Spatial variation of low energy photon flux creates concentrated and sparse radiation zones that may be used to induce …
Interface Engineering Of Lithium Metal Anodes Via Atomic And Molecular Layer Deposition,
2024
University of Arkansas, Fayetteville
Interface Engineering Of Lithium Metal Anodes Via Atomic And Molecular Layer Deposition, Xiangbo Meng
Mechanical Engineering Faculty Publications and Presentations
Rechargeable batteries are playing an ever-increasing important role in our society. Their performance (such as cell cyclability, safety, and lifespan) is critical for their applications. Among the various factors related to cell performance, interfaces, which ubiquitously exist between an electrode and an electrolyte, have some significant functions. They mostly evolve and degrade with cell cycling. Thus, an ideal interface should be physically and electrochemically stable and able to provide a compatible environment for electrolytes and electrodes in cells. To this end, interface engineering is needed and has become an important area. It has been achieved via different strategies. In the …
Effect Of Π-Conjugated Ligands And A* Site Organic Cations On The Energetic Properties And Photovoltaic Performance Of Metal Halide Perovskites,
2024
University of Kentucky
Effect Of Π-Conjugated Ligands And A* Site Organic Cations On The Energetic Properties And Photovoltaic Performance Of Metal Halide Perovskites, Harindi R. Atapattu
Theses and Dissertations--Chemistry
Metal halide perovskites have gained interest in optoelectronic applications such as photovoltaics, lasers, LEDs, transistors, and photodetectors due to their excellent semiconducting properties considering their low cost. Metal halide perovskite (HP) photovoltaics have rapidly increased in power conversion efficiency (PCE), which now exceeds 25%. HPs have gained attention in these applications due to their high tolerance towards defects, long charge carrier diffusion lengths, high charge carrier mobility, high optical absorption, and bandgaps that are tunable over a large range. Even though HP photovoltaic PCEs are improved these are still not commercially available due to them showing lower stability and energy …
Synthetic Strategies Toward The Development Of Stable Gold-Based Anticancer Agents And Their Mechanistic Insight,
2024
University of Kentucky
Synthetic Strategies Toward The Development Of Stable Gold-Based Anticancer Agents And Their Mechanistic Insight, Adedamola Arojojoye
Theses and Dissertations--Chemistry
Despite notable advancements in the design and synthesis of novel chemotherapeutic drugs, cancer continues to be a leading cause of death in the United States. Metallodrugs, especially Au complexes, have played a prominent role in the search for the next generation of chemotherapeutic agents. Herein, I report on the synthetic strategies towards the rational design of stable Au (Au)-based agents, study their reactivity in biological environment, and offer insights into the cytotoxic mechanism of action in cancer. Chemotherapeutic Au compounds exist mainly in +I or +III oxidation states. Repurposing of the Au(I) FDA approved auranofin for the treatment of diseases …
Stability Of Organic Metal Halide Perovskites,
2024
University of Kentucky
Stability Of Organic Metal Halide Perovskites, S S M Tareq Hossain
Theses and Dissertations--Chemistry
Perovskites have emerged as a promising candidate for low-cost production of solar cells. However, the most critical barrier for commercialization of perovskite solar cells (PSCs) is the inadequate stability of the organic metal halide perovskites (OMHPs). The degradation of OMHPs is induced by light, heat, air, and electrical bias. The known degradation pathways involve the oxidation of I- and Sn2+, dissolution of perovskites by moisture, irreversible reactions with water, ion migration, and ion segregation. To improve the stability of OMHPs various methods are adopted, such as additive engineering, perovskite surface treatment, and composition engineering. Surface ligands are used on top …
