The Influence Of Allostery Governing The Changes In Protein Dynamics Upon Substitution,
2023
Clemson University
The Influence Of Allostery Governing The Changes In Protein Dynamics Upon Substitution, Joseph Hess
All Dissertations
The focus of this research is to investigate the effects of allostery on the function/activity of an enzyme, human immunodeficiency virus type 1 (HIV-1) protease, using well-defined statistical analyses of the dynamic changes of the protein and variants with unique single point substitutions 1. The experimental data1 evaluated here only characterized HIV-1 protease with one of its potential target substrates. Probing the dynamic interactions of the residues of an enzyme and its variants can offer insight of the developmental importance for allosteric signaling and their connection to a protein’s function. The realignment of the secondary structure elements can …
The Investigation Of Singlet Fission From The Perspective Of Hierarchy Of Pure States (Hops),
2023
Southern Methodist University
The Investigation Of Singlet Fission From The Perspective Of Hierarchy Of Pure States (Hops), Tao (James) Chen
Chemistry Theses and Dissertations
This thesis provides a preliminary investigation of singlet fission from the perspective of Hierarchy of pure states (HOPS), which provides a numerical exact solution for the investigation of a series of open quantum systems. Since the inception of the concept of singlet fission about half a century ago, this photo-physical process has attracted the attention of a multitude of researchers and has been extensively studied theoretically and experimentally. However, these previous methods for the investigation of singlet fission focus more or less on tackling the underlying mechanisms of singlet fission from the perspective of perturbation. So far, the HOPS method …
A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino,
2023
The Graduate Center, City University of New York
A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo
Dissertations, Theses, and Capstone Projects
Terracotta lamps, known to the Romans as lucernae, are small, handheld, often decorated objects which provided ancient people light. To modern researchers, they serve as tools for dating stratigraphy and iconographic studies. Beyond their immediately apparent aesthetic and symbolic value, the chemical compositions of the clay of these lamps reflect their origin. This study complements archaeological typologies with chemometric analyses to describe 16 Late Republican and Imperial Roman lamps recovered from the villa at Poggio del Molino (PdM), Tuscany. These finds were recovered from the 2021 and 2022 PdM excavations. The combined approach of typology with X-ray Diffraction (XRD) …
Sers For The Detection Of Trace Materials,
2023
The Graduate Center, City University of New York
Sers For The Detection Of Trace Materials, Omari Kirkland
Dissertations, Theses, and Capstone Projects
In this dissertation are presented three projects that contribute to the body of research on SERS in the forensic, heritage, and semiconductor fields. The first project, Charge-Transfer mapping on GaN/Ag, a silver-decorated nanopillar semiconductor substrate fabricated from the GaN is used with the Raman probe Rhodamine 6 G (R6G) to map the effect of the nanofeatures on the CT resonance. The second project, in collaboration with Marco Leona from the Metropolitan Museum of Art, explores the use of AgNIFs to identify colorants used on textile fiber samples from four 19th century works of Japanese art. The final project analyzes the …
Metals And Metal Complexes In Diseases With A Focus On Covid-19: Facts And Opinions,
2023
The John Paul II Catholic University of Lublin
Metals And Metal Complexes In Diseases With A Focus On Covid-19: Facts And Opinions, Agnieszka Ścibior, Manuel Aureliano, Alvin A. Holder, Juan Llopis
Chemistry & Biochemistry Faculty Publications
In the present Special Issue on “Metals and Metal Complexes in Diseases with a Focus on COVID-19: Facts and Opinions”, an attempt has been made to include reports updating our knowledge of elements considered to be potential candidates for therapeutic applications and certain metal-containing species, which are extensively being examined towards their potential biomedical use due to their specific physicochemical properties. The Special Issue compiles data on the role of metals in COVID-19 and focuses on other illnesses and biological processes that affect metal metabolism. It consists of eight manuscripts, including five review articles and three original research papers (Figure …
Halide Exchange And Transport In Halide Perovskite Lattices,
2023
University of Nebraska-Lincoln
Halide Exchange And Transport In Halide Perovskite Lattices, Temban Acha Billy
Student Research Projects, Dissertations, and Theses - Chemistry Department
In recent years, metal-halide perovskites (MHPs) have risen quickly to prominence as promising materials across a variety of fields, from photovoltaics to optoelectronics in general. We show here a facile solution growth for creating a variety of mixed halide MAPbBr3-xIx crystals, which we will use to study halide exchange and transport in halide perovskites. We generated a calibration curve between the optical response and chemical composition in mixed Br/I MHPs at room temperature. All mixed Br/I MHP crystals were subjected to measurements of photoluminescence (PL) and Raman spectroscopy. A subset of mixed-halide MHP crystals exhibited multiple emission …
Carbon Dioxide Reduction On Large Area Liquid Metal Gallium-Indium Electrocatalysts,
2023
University of Arkansas, Fayetteville
Carbon Dioxide Reduction On Large Area Liquid Metal Gallium-Indium Electrocatalysts, Thomas Hollis
Chemistry & Biochemistry Undergraduate Honors Theses
Carbon dioxide (CO2) is widely known as a greenhouse gas that contributes to global warming due to the burning of fossil fuels. The carbon dioxide reduction reaction (CO2RR) is widely studied to reutilize CO2 to useful products, including methane, ethane, and carbon monoxide. This project studies the use of liquid metal gallium-indium as an electrocatalyst to perform CO2 reduction to carbon monoxide (CO) or possibly solid carbon in various solutions. Gallium-indium is characterized and studied through its “wetting” properties and adhesion to substrate foil through the measurement of contact angles inside solution. These liquid …
Mechanisms Of Formation Of Novel Guanine-Guanine Cross-Links As Major End Products During One-Electron Oxidation Of Guanine Derivatives,
2023
East Tennessee State University
Mechanisms Of Formation Of Novel Guanine-Guanine Cross-Links As Major End Products During One-Electron Oxidation Of Guanine Derivatives, Evan Dunn
Undergraduate Honors Theses
Guanine (G), as the most oxidizable base in DNA, is the major focus of studies of oxidation damage to DNA. The present thesis reports the first detailed characterization of G dimerization products potentially resulting from recombination of neutral G• radicals. Previous research has discovered a novel type of products of G• dimerization, D1 and D2, formed from one-electron oxidation of G derivatives. However, the mechanism of this dimerization remains elusive. While there appears to be a tautomeric equilibrium between two forms of G•, G(N1-H)• or G(N2-H)•, it remains unclear which intermediate participates in the formation of …
Collisional Excitation Of C2h- By H2: New Interaction Potential And Scattering Calculations,
2023
Missouri University of Science and Technology
Collisional Excitation Of C2h- By H2: New Interaction Potential And Scattering Calculations, Fabien Dumouchel, Ernesto Quintas-Sánchez, Christian Balança, Richard Dawes, François Lique, Nicole Feautrier
Chemistry Faculty Research & Creative Works
Interstellar Anions Play an Important Role in Astrochemistry as Being Tracers of the Physical and Chemical Conditions in Cold Molecular Clouds and Circumstellar Gas. the Local Thermodynamic Equilibrium is Generally Not Fulfilled in Media Where Anions Are Detected and Radiative and Collisional Data Are Required to Model the Observed Lines. the C2H- Anion Has Not Yet Been Detected in the Interstellar Medium; However, Collisional Data Could Be Used for Non-LTE Models that Would Help in Identifying the Most Intense Lines. for This Purpose, We Have Computed the First 4D Potential Energy Surface (PES) of the C2H--H2 Complex using an Explicitly …
Probing The Effect Of Nitrogen And Boron Doping On Structures, Properties, And Stability Of C20 Clusters,
2023
Kennesaw State University
Probing The Effect Of Nitrogen And Boron Doping On Structures, Properties, And Stability Of C20 Clusters, Ramsay Revennaugh, Martina Kaledin
Symposium of Student Scholars
Fullerenes are carbon molecules arranged in a closed hollow shell to form spherical-like structures. These clusters exist in various sizes, Cn, with the smallest being C20. C20, often when doped with other elements, has shown promise in creating new materials as a catalyst and as energy storage material. Here, we look at the existence of C20 doped with nitrogen or boron atoms using density functional theory (DFT). C20 is doped with one to three boron or nitrogen atoms, respectively, including the five different C18N2 / C18B2 …
Ab Initio Calculations Of Vibrational Spectra Of Model Peptides,
2023
Kennesaw State University
Ab Initio Calculations Of Vibrational Spectra Of Model Peptides, Katheryn Foust, Martina Kaledin
Symposium of Student Scholars
The function of biological molecules is closely related to their spatial structure and conformational dynamics. Therefore, understanding the structure and functions of small peptides contributes to gaining insight into the behavior of more complex systems. The peptide bond (-CO-NH-) is among the very important binding patterns in biochemistry. It links amino acids together, specifies rigidity to the protein backbone, and includes the two essential docking sites for hydrogen-bond-mediated protein folding and protein aggregation, namely, the C=O acceptor and the N-H donor parts. Therefore, the C=O (amide-I) and N-H (amide-A) vibrations provide sensitive and widely used probes into the structure of …
A Comparative Study Of Specific Enthalpy Of Aromatic Hydrocarbons With Simple Carbohydrates,
2023
Arkansas Tech University
A Comparative Study Of Specific Enthalpy Of Aromatic Hydrocarbons With Simple Carbohydrates, Kohl D. Kervin, Subha Pratihar
ATU Research Symposium
Calorimetry is an aspect of chemistry primarily focused on determining the enthalpy of reactions (∆Hrxn). In the bomb calorimetry technique, the heat of combustion of chemical compounds can be measured experimentally. From this data and the application of Hess’s Law, ∆the Hrxn of several chemical reactions can be determined. The technique of bomb calorimetry can be applied to food, fuels, pharmaceuticals, and many other fields. The objective of the present project is to determine the specific enthalpy of various simple carbohydrates (naturally occurring sugars) through bomb calorimetry and compare it with that of aromatic hydrocarbons.
By performing benzoic acid standardization …
Additivity Of Diene Substituent Gibbs Free Energy Contributions For Diels–Alder Reactions Between Me2c=Cme2 And Substituted Cyclopentadienes,
2023
Northern Illinois University
Additivity Of Diene Substituent Gibbs Free Energy Contributions For Diels–Alder Reactions Between Me2c=Cme2 And Substituted Cyclopentadienes, Thomas M. Gilbert, Austin S. Flemming, Brendan C. Dutmer
Faculty Peer-Reviewed Publications
Systematic computational studies of pericyclic Diels–Alder reactions between (H3C)2C═C(CH3)2, 1, and all permutations of substituted cyclopentadienes c-C5R1R2R3R4R5aR5b (R = H, CH3, CF3, F) allowed isolation of substitutional effects on Gibbs free energy barrier heights and reaction Gibbs free energies. “Average Substitution Gibbs Free Energy Correction” ΔGASC#‡/ΔGASC# values for each substituent in each position appeared to be additive. Substituent effects on barriers showed interesting contrasts. Methyl substitution at positions 5a and 5b increased barriers significantly, while substitution at all other positions had essentially no impact. In contrast, fluoro substitution at positions 5a and 5b lowered barriers more than substitution at other …
Scanning Probe And Spectroscopic Investigations Of Polarization-Driven Electronic Interactions At The Inorganic/Organic Interface Of 2d Materials,
2023
University of Massachusetts Amherst
Scanning Probe And Spectroscopic Investigations Of Polarization-Driven Electronic Interactions At The Inorganic/Organic Interface Of 2d Materials
Doctoral Dissertations
My thesis focuses on understanding the changes in electronic properties of two-dimensional materials produced by surface interactions not limited to charge exchange. Recent work from our group demonstrated that both small molecules and polymers can function as effective charge dopants for monolayered 2D materials such as MoS2 and graphene, changing the Fermi energy by either donating or accepting electron density to/from the 2D material. Additionally, the underlying support material was found to play a significant role, where higher dielectric constant supports result in larger magnitude of Fermi energy shift of the 2D material because less of the dopant interaction …
Modeling Excited State Processes In Molecular Aggregates By Constructing An Adaptive Basis For The Hierarchy Of Pure States,
2023
Southern Methodist University
Modeling Excited State Processes In Molecular Aggregates By Constructing An Adaptive Basis For The Hierarchy Of Pure States, Leonel Varvelo
Chemistry Theses and Dissertations
Simulating excitation energy transfer (EET) in molecular materials is of crucial importance for the development of and understanding of materials such as organic photovoltaics and photosynthetic systems and further development of novel materials. The Hierarchy of Pure States (HOPS) is an exact framework for the time evolution of an open quantum system in which a hierarchy of stochastic wave functions are propagated in time. The adaptive HOPS (adHOPS) method achieves size-invariant scaling with the number of simulated molecules for sufficiently large aggregates by using an adaptive basis that moves with the excitation through the material. To demonstrate the power of …
Diffractive Imaging Of Laser Induced Molecular Reactions With Kiloelectron-Volt Ultrafast Electron Diffraction,
2023
University of Nebraska–Lincoln
Diffractive Imaging Of Laser Induced Molecular Reactions With Kiloelectron-Volt Ultrafast Electron Diffraction, Yanwei Xiong
Theses, Dissertations, and Student Research: Department of Physics and Astronomy
Capturing the structural changes during a molecular reaction with ultrafast electron diffraction (UED) requires a high spatiotemporal resolution and sufficiently high signal-to-noise to record the signals with high fidelity. In this dissertation, I have focused on the development of a tabletop gas phase keV-UED setup with a femtosecond temporal resolution. A DC electron gun was employed to generate electron pulses with a high repetition rate of 5 kHz. The space charge effect in the electron pulse was ameliorated by compressing the 90 keV electron pulse longitudinally with a time varying electric field in an RF cavity. The velocity mismatch between …
Synthesis And Characterization Of New Azo Dyes Derived From Acyclovir And Sulfamethoxazole And Study Their Biological Activity,
2023
Hadhrahout University
Synthesis And Characterization Of New Azo Dyes Derived From Acyclovir And Sulfamethoxazole And Study Their Biological Activity, Abdul Rahman Y. Wahoud, Thanaa Shriteh, Ali Yousef, Mohammad Mazen Kondakji
Hadhramout University Journal of Natural & Applied Sciences
In this research, two new azo dyes, 9-(2-Hydroxy-ethoxymethyl)-2-(2-hydroxy5nitrophenylazo)-1,9-dihydro-purin-6-one and 4-(2-Hydroxy-napHthalen-1-ylazo)-N-(5-methyl-isoxazol-3-yl)-benzenesulfonamide, derived from Acyclovir and Sulfamethoxazole was synthesized. The first dye synthesis was started by diazation of acyclovir, then combined with 4-nitrophenol activated with potassium hydroxide 10%, yielding 80%, and its purity was verified by thin layer chromatography (TLC). The second dye synthesis was started by diazation of Sulfamethoxazole then combined with β-naphthol activated with potassium hydroxide 10%, yielding 87%, and its purity was verified by thin layer chromatography (TLC). The identity of the resulting pigments was determined based on spectroscopic methods such as infrared spectroscopy, proton nuclear magnetic resonance spectrum …
Anodic Electrocatalysis Of Glycerol Oxidation For Hybrid Alkali/Acid Electrolytic Hydrogen Generation,
2023
Key Laboratory of Jiangxi Province for Persistent Pollutants Control, National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, Jiangxi, China;CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China
Anodic Electrocatalysis Of Glycerol Oxidation For Hybrid Alkali/Acid Electrolytic Hydrogen Generation, Xin Feng, Bo-Wen Liu, Ke-Xin Guo, Lin-Feng Fan, Gen-Xiang Wang, Su-Qin Ci, Zhen-Hai Wen
Journal of Electrochemistry
Electrolytic hydrogen production is heavily restricted by high-energy consumption majorly due to the relatively high potential of anodic oxygen evolution reaction (OER). Development of OER-alternative reaction at the anode has been recently proposed as a promising pathway to address the associated issues. In this work, we report a hybrid acid/alkali dual-electrolyte electrolyzer by coupling acidic hydrogen evolution reaction (HER) using commercial Pt/C cathode with alkaline Electrocatalytic glycerol oxidation (GOR) which is implemented by developing a nickel foam (NF) supporting Co3O4 nanosheets anode that shows low overpotential and high selectivity toward GOR for formate production. The hybrid acid/alkali …
Table Of Contents,
2023
Chinese Chemical Society | Xiamen University
Preface To Special Issue On Electrocatalysis And Electrosynthesis,
2023
College of Chemistry, Nankai University, Tianjin 30071, China
Preface To Special Issue On Electrocatalysis And Electrosynthesis, Fang-Yi Cheng, Shuang-Yin Wang, Tian-Hua Zhou
Journal of Electrochemistry
No abstract provided.
