Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- The British University in Egypt (9)
- Chapman University (4)
- Furman University (4)
- University of Nebraska - Lincoln (3)
- Louisiana State University (2)
-
- Old Dominion University (2)
- Washington University in St. Louis (2)
- Western Kentucky University (2)
- Ateneo de Manila University (1)
- City University of New York (CUNY) (1)
- Cleveland State University (1)
- Florida International University (1)
- Liberty University (1)
- Portland State University (1)
- Sheridan College (1)
- Technological University Dublin (1)
- University of Arkansas, Fayetteville (1)
- University of Connecticut (1)
- University of Dayton (1)
- University of Kentucky (1)
- University of Minnesota Morris Digital Well (1)
- University of Texas Rio Grande Valley (1)
- Western University (1)
- Keyword
-
- Atmospheric chemistry (2)
- Catalytic activity (2)
- Chemistry (2)
- DFT (2)
- Glucose electro-oxidation (2)
-
- Oxidation (2)
- Photocatalysis (2)
- SERS (2)
- Stability (2)
- Adsorption (1)
- Aerosols (1)
- Air-water interface (1)
- Aromatic compounds (1)
- Au (1)
- Bacteria (1)
- Basin-Hopping (1)
- Benzosilole (1)
- Bimetallic nanoparticles (1)
- Binge Drinking -- Metabolism (1)
- Biosensor (1)
- Brucellosis (1)
- CO Oxidation (1)
- CO oxidation; potassium poisoning; gold nanoparticles; ceria-zirconia; NO oxidation; propane combustion (1)
- Carbamates (tradename) (1)
- Carbohydrates (1)
- Carbon monoxide (1)
- Catalyst (1)
- Chains (1)
- Chemisorption (1)
- Chemoselectivity (1)
- Publication
-
- Chemical Engineering (8)
- Chemistry Publications (6)
- Chemistry Faculty Publications (3)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (2)
- Chemistry Faculty Publications and Presentations (2)
-
- Electrical & Systems Engineering Publications and Presentations (2)
- Faculty Publications (2)
- Masters Theses & Specialist Projects (2)
- Xiao Cheng Zeng Publications (2)
- Books/Book chapters (1)
- Chemistry & Biochemistry Faculty Publications (1)
- Chemistry Education Materials (1)
- Department of Chemistry: Dissertations, Theses, and Student Research (1)
- FIU Electronic Theses and Dissertations (1)
- Nanotechnology Research Centre (1)
- Open Educational Resources (1)
- Physics Faculty Publications (1)
- Publications and Scholarship (1)
- SURF Posters and Papers (1)
- Senior Honors Theses (1)
- Student Scholar Symposium Abstracts and Posters (1)
- University Administration Publications (1)
- University Libraries Faculty Publications and Presentations (1)
Articles 1 - 30 of 43
Full-Text Articles in Chemistry
Unspecified Verticality Of Franck-Condon Transitions, Absorption And Emission Spectra Of Cyanine Dyes, And A Classically Inspired Approximation, Joseph D. Alia, Joseph A. Flack
Unspecified Verticality Of Franck-Condon Transitions, Absorption And Emission Spectra Of Cyanine Dyes, And A Classically Inspired Approximation, Joseph D. Alia, Joseph A. Flack
Chemistry Publications
The computed vertical energy, Ev,a/f, from the equilibrium geometry of the initial electronic state is frequently considered as representative of the experimental excitation/emission energy, Eabs/fl = hc/λmax. Application of the quantum mechanical version of the Franck–Condon principle does not involve precise specification of nuclear positions before, after, or during an electronic transition. Moreover, the duration of an electronic transition is not experimentally accessible in spectra with resolved vibrational structure. It is shown that computed vibronic spectra based on TDDFT methods and application of quantum mechanical FC analysis predict Eabs = hc/λmax …
Surface Enhanced Raman Spectroscopy (Sers) As A Nanoscale Adsorption Phenomenon: Development Of Tailored Nanomaterials For Applications In Drug Detection, Chiara Deriu
FIU Electronic Theses and Dissertations
Surface Enhanced Raman Spectroscopy (SERS) is an analytical technique in which nanostructured substrates amplify the inherently weak Raman signal of an adsorbed species by several orders of magnitude, enabling the detection of trace compounds, up to the single molecule level. While this may be an exceptional tool for any analytical scientist, SERS is at present relegated to the role of academic sensation, and is underutilized in everyday analytical practice. The SERS community is increasingly attributing this setback to a poor understanding of nanoscale surfaces and their chemical environment; since molecular adsorption at the nanostructured surface enables SERS detection, uncertainty about …
Oxidation Of Phenolic Aldehydes By Ozone And Hydroxyl Radicals At The Air-Water Interface, Md Sohel Rana, Marcelo I. Guzman
Oxidation Of Phenolic Aldehydes By Ozone And Hydroxyl Radicals At The Air-Water Interface, Md Sohel Rana, Marcelo I. Guzman
Chemistry Faculty Publications
Biomass burning releases highly reactive methoxyphenols into the atmosphere, which can undergo heterogeneous oxidation and act as precursors for secondary organic aerosol (SOA) formation. Understanding the reactivity of such methoxyphenols at the air–water interface is a matter of major atmospheric interest. Online electrospray ionization mass spectrometry (OESI-MS) is used here to study the oxidation of two methoxyphenols among three phenolic aldehydes, 4-hydroxybenzaldehyde, vanillin, and syringaldehyde, on the surface of water. The OESI-MS results together with cyclic voltammetry measurements at variable pH are integrated into a mechanism describing the heterogeneous oxidative processing of methoxyphenols by gaseous ozone (O3) and …
Single‐Molecule 3d Orientation Imaging Reveals Nanoscale Compositional Heterogeneity In Lipid Membranes, Jin Lu, Hesam Mazidi, Tianben Ding, Oumeng Zhang, Matthew D. Lew
Single‐Molecule 3d Orientation Imaging Reveals Nanoscale Compositional Heterogeneity In Lipid Membranes, Jin Lu, Hesam Mazidi, Tianben Ding, Oumeng Zhang, Matthew D. Lew
Electrical & Systems Engineering Publications and Presentations
In soft matter, thermal energy causes molecules to continuously translate and rotate, even in crowded environments, thereby impacting the spatial organization and function of most molecular assemblies, such as lipid membranes. Directly measuring the orientation and spatial organization of large collections (>3000 molecules μm−2) of single molecules with nanoscale resolution remains elusive. In this paper, we utilize SMOLM, single‐molecule orientation localization microscopy, to directly measure the orientation spectra (3D orientation plus “wobble”) of lipophilic probes transiently bound to lipid membranes, revealing that Nile red's (NR) orientation spectra are extremely sensitive to membrane chemical composition. SMOLM images resolve …
Effect Of Oxidation Level On The Interfacial Water At The Graphene Oxide-Water Interface: From Spectroscopic Signatures To Hydrogen-Bonding Environment, Rolf David, Aashish Tuladhar, Le Zhang, Christopher Arges, Revati Kumar
Effect Of Oxidation Level On The Interfacial Water At The Graphene Oxide-Water Interface: From Spectroscopic Signatures To Hydrogen-Bonding Environment, Rolf David, Aashish Tuladhar, Le Zhang, Christopher Arges, Revati Kumar
Faculty Publications
The interfacial region of the graphene oxide (GO)-water system is nonhomogenous due to the presence of two distinct domains: an oxygen-rich surface and a graphene-like region. The experimental vibrational sum-frequency generation (vSFG) spectra are distinctly different for the fully oxidized GO-water interface as compared to the reduced GO-water case. Computational investigations using ab initio molecular dynamics were performed to determine the molecular origins of the different spectroscopic features. The simulations were first validated by comparing the simulated vSFG spectra to those from the experiment, and the contributions to the spectra from different hydrogen bonding environments and interfacial water orientations were …
Mechanism And Chemoselectivity For Hocl-Mediated Oxidation Of Zinc-Bound Thiolates, Lindsay Zumwalt, Arden Perkins, O. Maduka Ogba
Mechanism And Chemoselectivity For Hocl-Mediated Oxidation Of Zinc-Bound Thiolates, Lindsay Zumwalt, Arden Perkins, O. Maduka Ogba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Quantum mechanical calculations reveal the preferred mechanism and origins of chemoselectivity for HOCl‐mediated oxidation of zinc‐bound thiolates implicated in bacterial redox sensing. Distortion/interaction models show that minimizing geometric distortion at the zinc complex during the rate‐limiting nucleophilic substitution step controls the mechanistic preference for OH over Cl transfer with HOCl and the chemoselectivity for HOCl over H2O2.
Mechanism And Chemoselectivity For Hocl-Mediated Oxidation Of Zinc-Bound Thiolates, Lindsay Zumwalt, Arden Perkins, O. Maduka Ogba
Mechanism And Chemoselectivity For Hocl-Mediated Oxidation Of Zinc-Bound Thiolates, Lindsay Zumwalt, Arden Perkins, O. Maduka Ogba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Quantum mechanical calculations reveal the preferred mechanism and origins of chemoselectivity for HOCl‐mediated oxidation of zinc‐bound thiolates implicated in bacterial redox sensing. Distortion/interaction models show that minimizing geometric distortion at the zinc complex during the rate‐limiting nucleophilic substitution step controls the mechanistic preference for OH over Cl transfer with HOCl and the chemoselectivity for HOCl over H2O2.
The Statue Of Liberty Laboratory Activity: The Chemistry Of Copper, Jihyun Kim, Marcus D. Allen
The Statue Of Liberty Laboratory Activity: The Chemistry Of Copper, Jihyun Kim, Marcus D. Allen
Open Educational Resources
In this lab activity we observe chemical changes of copper in acidic conditions, salt water, and a mixture of lemon juice and vinegar and salt, and we discuss whether the Statue of Liberty would hold as much cultural icon today had the Lady Statue remain the original shiny brown color.
H-Atom Ladder Operator Revisited, Carl W. David
H-Atom Ladder Operator Revisited, Carl W. David
Chemistry Education Materials
An error laden note (Am. J. Phys., 34, 984,(1966)) concerning the ladder operator solution to the hydrogen atom electronic energy levels is corrected.
Probing The Surface Acidity Of Supported Aluminum Bromide Catalysts, Md Ashraful Abedin, Swarom Kanitkar, Nitin Kumar, Zi Wang, Kunlun Ding, Graham Hutchings, James J. Spivey
Probing The Surface Acidity Of Supported Aluminum Bromide Catalysts, Md Ashraful Abedin, Swarom Kanitkar, Nitin Kumar, Zi Wang, Kunlun Ding, Graham Hutchings, James J. Spivey
Faculty Publications
Solid acid catalysis is an important class of reactions. The principal advantages of solid acid catalysts as compared to their corresponding fluid acids include minimal waste and ease of product separation. One type of these catalysts is based on aluminum bromide (Al2Br6), which is a stronger Lewis acid than Al2Cl6. In this report, Al(2)Br(6)is grafted on commercial mesoporous silica (CMS), SBA-15 and silica gel to create a solid catalyst similar to the silica-supported Al(2)Cl(6)superacid. These supported Al(2)Br(6)catalysts were characterized by NH3-Temperature Programmed Desorption (TPD), pyridine Diffuse Reflectance for Infrared Fourier Transform Spectroscopy (DRIFTS) and Magic Angle Spinning Nuclear Magnetic Resonance …
Designing A Reactor Chamber For Hot Electron Chemistry On Bimetallic Plasmonic Nanoparticles, Bryn Merrill, Bingjie Zhang, Jerry Larue
Designing A Reactor Chamber For Hot Electron Chemistry On Bimetallic Plasmonic Nanoparticles, Bryn Merrill, Bingjie Zhang, Jerry Larue
SURF Posters and Papers
Catalysis provides pathways for efficient and selective chemical reactions by lowering the energy barriers for desired products. Gold nanoparticles (AuNPs) show excellent promise as plasmonic catalysts. Plasmonic materials have localized surface plasmon resonances, oscillations of the electron bath at the surface of a nanoparticle, that generate energetically intense electric fields which rapidly decay into energetically excited electrons. The excited electrons have the potential to destabilize atoms strongly bound to the catalysts through occupation of antibonding orbitals. Tuning the antibonding orbitals to make them accessible for occupancy by electrons is achieved by coating the AuNP in a thin layer of another …
How Oxygen-Binding Affects Structural Evolution Of Even-Sized Gold Anion Clusters. (Size Range 20 To 34), David Brunken-Deibert
How Oxygen-Binding Affects Structural Evolution Of Even-Sized Gold Anion Clusters. (Size Range 20 To 34), David Brunken-Deibert
Department of Chemistry: Dissertations, Theses, and Student Research
We report a joint anion photoelectron spectroscopy (PES) and theoretical study to investigate the effect of O2-binding on the mid-sized even-numbered gold clusters, Aun− (n = 20−34), a special size region of bare gold clusters that entail rich forms of structural evolution and transformation. Specifically, within this size range, bare Au20− is a highly-symmetric pyramidal cluster, bare Au21-25− are flat-planar or hollow-tubular clusters, bare Au26− is the smallest core-shell gold cluster, while bare Au34− is a magic-number/fluxional core-shell cluster with the high-symmetry tetrahedral Au4 core. In light of the strong …
Chemistry And Biochemistry Authored Faculty Publications: Snapshot Of The Ranking Of Journals In Which They Published Based On Data From Journal Citation Reports (Jcr), Lutishoor Salisbury, Yang Tian, Jeremy Smith
Chemistry And Biochemistry Authored Faculty Publications: Snapshot Of The Ranking Of Journals In Which They Published Based On Data From Journal Citation Reports (Jcr), Lutishoor Salisbury, Yang Tian, Jeremy Smith
University Libraries Faculty Publications and Presentations
This report presents a snapshot of the research output of the Chemistry and Biochemistry Department at the University of Arkansas for the period 2015-2019. The contents of the report were generated using Web of Science Core Collection databases and the Journal Citation Report only. It highlights the journals in which the researchers published and the ranking of those journals.
Synthesis Of Cds/Zns Core/Shell Semiconductor Nanoparticles, Austin Skyler Antle
Synthesis Of Cds/Zns Core/Shell Semiconductor Nanoparticles, Austin Skyler Antle
Masters Theses & Specialist Projects
Core/shell semiconductor nanoparticles are of great interest as photocatalysts due to their large surface area per volume and tunable band gaps. The synthesis of core/shell semiconductor nanoparticles has traditionally involved the use of binding ligands to ensure the particles do not aggregate. These binding ligands lower the surface area of the nanoparticles though, reducing their overall efficiency. Ionic liquids have been found to be capable of acting as both solvents and stabilizing agents for synthesis of catalysts with highly active surfaces. Our experiments focus on the synthesis of CdS/ZnS core/shell nanoparticles with the ionic liquid 1-butyl-3-methylimidazolium methyl sulfate, [BMIM][MeSO4], acting …
Application Of Potassium Ion Deposition In Determining The Impact Of Support Reducibility On Catalytic Activity Of Au/Ceria-Zirconia Catalysts In Co Oxidation, No Oxidation, And C3h8 Combustion, Ewa M. Iwanek (Nee Wilczkowska), Leonarda F. Liotta, Shazam Williams, Linjie Hu, Krishelle Calilung, Giuseppe Pantaleo, Zbigniew Kaszkur, Donald W. Kirk, Marek Gliński
Application Of Potassium Ion Deposition In Determining The Impact Of Support Reducibility On Catalytic Activity Of Au/Ceria-Zirconia Catalysts In Co Oxidation, No Oxidation, And C3h8 Combustion, Ewa M. Iwanek (Nee Wilczkowska), Leonarda F. Liotta, Shazam Williams, Linjie Hu, Krishelle Calilung, Giuseppe Pantaleo, Zbigniew Kaszkur, Donald W. Kirk, Marek Gliński
Publications and Scholarship
The purpose of the study was to show how a controlled, subtle change of the reducibility of the support by deposition of potassium ions impacts the activity of gold catalysts. Since the activity of supported gold catalysts in carbon monoxide oxidation is known to strongly depend on the reducibility of the support, this reaction was chosen as the model reaction. The results of tests conducted in a simple system in which the only reagents were CO and O2 showed good agreement with the CO activity trend in tests performed in a complex stream of reagents, which also contained CH …
Benzosiloles With Crystallization-Induced Emission Enhancement Of Electrochemiluminescence: Synthesis, Electrochemistry, And Crystallography, Liuqing Yang, Donghyun Koo, Jackie Wu, Jonathan M. Wong, Tyler Day, Ruizhong Zhang, Harshana Kolongoda, Kehan Liu, Jian Wang, Zhifeng Ding, Brian Pagenkopf
Benzosiloles With Crystallization-Induced Emission Enhancement Of Electrochemiluminescence: Synthesis, Electrochemistry, And Crystallography, Liuqing Yang, Donghyun Koo, Jackie Wu, Jonathan M. Wong, Tyler Day, Ruizhong Zhang, Harshana Kolongoda, Kehan Liu, Jian Wang, Zhifeng Ding, Brian Pagenkopf
Chemistry Publications
Crystallization-induced emission enhancement (CIEE) was demonstrated for the first time for electrochemilunimescence (ECL) with two new benzosiloles. Compared with their solution, the films of the two benzosiloles gave CIEE of 24 times and 16 times. The mechanism of the CIEE-ECL was examined by spooling ECL spectroscopy, X-ray crystal structure analysis, photoluminescence, and DFT calculation. This CIEE-ECL system is a complement to the well-established aggregation-induced emission enhancement (AIEE) systems. Unique intermolecular interactions are noted in the crystalline chromophore. The first heterogeneous ECL system is established for organic compounds with highly hydrophobic properties.
Hot Electron Chemistry On Bimetallic Plasmonic Nanoparticles, Bryn E. Merrill, Bingjie Zhang, Jerry Larue
Hot Electron Chemistry On Bimetallic Plasmonic Nanoparticles, Bryn E. Merrill, Bingjie Zhang, Jerry Larue
Student Scholar Symposium Abstracts and Posters
Catalysis provides pathways for efficient and selective chemical reactions through the lowering of energy barriers for desired products. Gold nanoparticles (AuNP) show excellent promise as plasmonic catalysts. Localized surface plasmon resonances are oscillations of the electron bath at the surface of a nanoparticle that generate energetically intense electric fields and rapidly decay into energetically excited electrons. The excited electrons have the potential to destabilize strongly bound oxygen atoms through occupation of accessible anti-bonding orbitals. Tuning the anti-bonding orbitals to make them accessible for occupancy will be achieved by coating the AuNP in a thin layer of another transition metal, such …
An Investigation Into The Molecular Dynamics Of The Laser Induced Dissociation Of 2-Bromoethanol, Kirk French
An Investigation Into The Molecular Dynamics Of The Laser Induced Dissociation Of 2-Bromoethanol, Kirk French
Senior Honors Theses
The unimolecular dissociation of 2-bromoethanol is investigated using computational chemistry methods both to test the reliability of the theories and methods of computational chemistry and to explore the internal mechanism of the dissociation. The dissociation of the bromine ion from 2-bromoethanol was experimentally observed in a previous publication by Ratliff et. al. These experimental results were compared in this thesis to computational calculations of their research. The method of TD-B3LYP proved to be inadequate in this venture except for the lowest energies of the most stable conformer of 2-bromoethanol. However, interesting mechanisms were found such as the formation of HBr …
Monitoring And Identifying The Rhodamine 6g-Hydroxide Ion Reaction Using In-Situ, Surface-Enhanced Raman Spectroscopy, Ryan Lamb
Masters Theses & Specialist Projects
An effective method for monitoring chemical reactions is necessary to better understand their mechanisms and kinetics. Effective reaction monitoring requires a spectroscopy technique with fast data acquisition, high sensitivity, structure-to-spectrum correlation, and low solvent interference. Surface-enhanced Raman spectroscopy (SERS) provides these features, which makes it a valuable tool for monitoring reactions. To obtain the Raman enhancement, metallic nanostructures typically made of silver or gold are aggregated using a salt. The nanoparticles aggregates must then be stabilized using a surfactant to use this method in situ due to eventual nanoparticle precipitation. In this study, gold nanoparticles stabilized with sodium dodecyl sulfate …
Ni-Au Anodic Nano-Electrocatalyst For Direct Glucose Fuel Cells, Yaser M. Asal Mr., Islam M. Al-Akraa Dr, Ahmad M. Mohammad Prof, Aya S. Abdulhalim Eng
Ni-Au Anodic Nano-Electrocatalyst For Direct Glucose Fuel Cells, Yaser M. Asal Mr., Islam M. Al-Akraa Dr, Ahmad M. Mohammad Prof, Aya S. Abdulhalim Eng
Chemical Engineering
This study aims at the sequential assembling of a nickel oxide (NiOx: cauliflower-like nanostructure, 90 nm) and gold (Au; spherical, 95 nm in an average particle size) onto the GC surface nanocatalyst on a glassy carbon (GC) electrode (will be abbreviated as Ni-Au/GC) for the glucose electro−oxidation (GO); the principal anodic reaction in the direct glucose fuel cells (DGFCs). The charge of the Ni deposition on the GC surface (will be abbreviated as Ni/GC electrode) was initially optimized to obtain the highest catalytic activity toward GO which attained at (339.8 Ag−1) by applying 15 mC in the Ni deposition. Yet, …
Enhanced Glucose Electrooxidation At Ni-Cu Binary Oxide Nanocatalyst, Yaser M. Asal Mr., Islam M. Al-Akraa Dr, Ahmad M. Mohammad Prof, Mahmoud M. Abuzaied Eng
Enhanced Glucose Electrooxidation At Ni-Cu Binary Oxide Nanocatalyst, Yaser M. Asal Mr., Islam M. Al-Akraa Dr, Ahmad M. Mohammad Prof, Mahmoud M. Abuzaied Eng
Chemical Engineering
The aim of this study is to fabricate a nickel (NiOx) and copper (CuOx) oxide nanocatalyst on a glassy carbon (GC) electrode (will be abbreviated as Ni-Cu/GC) for glucose oxidation (GO). A sequential electrodepositon mode was applied to assemble NiOx and CuOx in the fabrication scheme. The optimization of Ni loading on the GC surface (will be abbreviated as Ni/GC electrode) was achieved first to attain the maximum catalytic efficiency in terms of the specific current toward GO. This (409 Ag-1)was obtained by applying 15 mC/cm2 in the deposition of Ni. However, unfortunately the NiOx/GC could not …
Quantitative Trait Loci (Qtl) Underlying Phenotypic Variation In Bioethanol-Related Processes In Neurospora Crassa, Joshua C. Waters, Deval Jhaveri, Justin C. Biffinger, Kwangwon Lee
Quantitative Trait Loci (Qtl) Underlying Phenotypic Variation In Bioethanol-Related Processes In Neurospora Crassa, Joshua C. Waters, Deval Jhaveri, Justin C. Biffinger, Kwangwon Lee
Chemistry Faculty Publications
Bioethanol production from lignocellulosic biomass has received increasing attention over the past decade. Many attempts have been made to reduce the cost of bioethanol produc- tion by combining the separate steps of the process into a single-step process known as consolidated bioprocessing. This requires identification of organisms that can efficiently decompose lignocellulose to simple sugars and ferment the pentose and hexose sugars lib- erated to ethanol. There have been many attempts in engineering laboratory strains by add- ing new genes or modifying genes to expand the capacity of an industrial microorganism. There has been less attention in improving bioethanol-related processes …
Electrochemical Studies Of Cobalt(Ii) Diphenylazodioxide Complexes, Lakshmi Balarama, Kylin A. Emhoff, Ahmed M.H. Salem, Jovana Hanna, Mohamed N. Alsabony, Mekki Bayachou, Jerry Mundell, W. Christropher Boyd
Electrochemical Studies Of Cobalt(Ii) Diphenylazodioxide Complexes, Lakshmi Balarama, Kylin A. Emhoff, Ahmed M.H. Salem, Jovana Hanna, Mohamed N. Alsabony, Mekki Bayachou, Jerry Mundell, W. Christropher Boyd
Chemistry Faculty Publications
The electrochemical behavior of the unusual cobalt(II) diphenylazodioxide complex salts [Co(az)4](PF6)2 1 and [Co(bpy)(az)2](PF6)2 2 has been studied by cyclic voltammetry. Each complex displays two quasireversible redox couples, which are proposed to correspond to a reduction of Co(II) to Co(I), followed by a ligand-based reduction. Irreversible reductions of 1 are observed at more negative potentials, and are proposed to arise from deposition of elemental Co and the decomposition of transiently formed Co(-I) species. Spectroelectrochemical experiments on both 1 and 2, involving electrolytic reduction followed by reoxidation, are consistent with …
Td-Dft Spin-Adiabats With Analytic Nonadiabatic Derivative Couplings, Nicole Bellonzi, Ethan Alguire, Shervin Fatehi, Yihan Shao, Joseph E. Subotnik
Td-Dft Spin-Adiabats With Analytic Nonadiabatic Derivative Couplings, Nicole Bellonzi, Ethan Alguire, Shervin Fatehi, Yihan Shao, Joseph E. Subotnik
Chemistry Faculty Publications and Presentations
We present an algorithm for efficient calculation of analytic nonadiabatic derivative couplings between spin-adiabatic, time-dependent density functional theory states within the Tamm-Dancoff approximation. Our derivation is based on the direct differentiation of the Kohn-Sham pseudowavefunction using the framework of Ou et al. Our implementation is limited to the case of a system with an even number of electrons in a closed shell ground state, and we validate our algorithm against finite difference at an S1/T2 crossing of benzaldehyde. Through the introduction of a magnetic field spin-coupling operator, we break time-reversal symmetry to generate complex valued nonadiabatic derivative …
A Possible Unaccounted Source Of Atmospheric Sulfate Formation: Amine-Promoted Hydrolysis And Non-Radical Oxidation Of Sulfur Dioxide, Shixian Wang, Xiao Cheng Zeng, Hui Li, Joseph S. Francisco
A Possible Unaccounted Source Of Atmospheric Sulfate Formation: Amine-Promoted Hydrolysis And Non-Radical Oxidation Of Sulfur Dioxide, Shixian Wang, Xiao Cheng Zeng, Hui Li, Joseph S. Francisco
Xiao Cheng Zeng Publications
Numerous field and laboratory studies have shown that amines, especially dimethylamine (DMA), are crucial to atmospheric particulate nucleation. However, the molecular mechanism by which amines lead to atmospheric particulate formation is still not fully understood. Herein, we show that DMA molecules can also promote the conversion of atmospheric SO2 to sulfate. Based on ab initio simulations, we find that in the presence of DMA, the originally endothermic and kinetically unfavourable hydrolysis reaction between gaseous SO2 and water vapour can become both exothermic and kinetically favourable. The resulting product, bisulfite NH2(CH3)2+ ∙ HSO …
Nanoscale Colocalization Of Fluorogenic Probes Reveals The Role Of Oxygen Vacancies In The Photocatalytic Activity Of Tungsten Oxide Nanowires, Meikun Shen, Tianben Ding, Steven T. Hartman, Fudong Wang, Christina Krucylak, Zheyu Wang, Che Tan, Bo Yin, Rohan Mishra, Matthew D. Lew, Bryce Sadtler
Nanoscale Colocalization Of Fluorogenic Probes Reveals The Role Of Oxygen Vacancies In The Photocatalytic Activity Of Tungsten Oxide Nanowires, Meikun Shen, Tianben Ding, Steven T. Hartman, Fudong Wang, Christina Krucylak, Zheyu Wang, Che Tan, Bo Yin, Rohan Mishra, Matthew D. Lew, Bryce Sadtler
Electrical & Systems Engineering Publications and Presentations
Defect engineering is a strategy that has been widely used to design active semiconductor photocatalysts. However, understanding the role of defects, such as oxygen vacancies, in controlling photocatalytic activity remains a challenge. Here, we report the use of chemically triggered fluorogenic probes to study the spatial distribution of active regions in individual tungsten oxide nanowires using super-resolution fluorescence microscopy. The nanowires show significant heterogeneity along their lengths for the photocatalytic generation of hydroxyl radicals. Through quantitative, coordinate-based colocalization of multiple probe molecules activated by the same nanowires, we demonstrate that the nanoscale regions most active for the photocatalytic generation of …
Development Of A Novel Highly-Sensitive Brucellosis Sensor Based On Surface Plasmon Resonance Spectroscopy, Amal Kasry, Ihab Adly, Asharf Sayour, Hossam Sayour
Development Of A Novel Highly-Sensitive Brucellosis Sensor Based On Surface Plasmon Resonance Spectroscopy, Amal Kasry, Ihab Adly, Asharf Sayour, Hossam Sayour
Nanotechnology Research Centre
Brucellosis is considered a significant health threat, it is an infectious disease caused by the bacteria Brucella, which can spread from animals to humans causing severe diseases. Through this project, we aim to develop a very highly sensitive biosensor to detect Brucella early before spreading. This sensor is based on surface plasmon resonance (SPR) technique, which is used to analyze kinetics of interaction between biomolecules. It can detect down to picomolar concentrations of some proteins.
A Spin-Coated Tiox/Pt Nanolayered Anodic Catalyst For The Direct Formic Acid Fuel Cells, Islam M. Al-Akraa, Ahmad M. Mohammad Prof
A Spin-Coated Tiox/Pt Nanolayered Anodic Catalyst For The Direct Formic Acid Fuel Cells, Islam M. Al-Akraa, Ahmad M. Mohammad Prof
Chemical Engineering
The CO poisoning of the platinum anodic catalyst which typically functions the catalytic deterioration of the direct formic acid fuel cells could be minimized with a simple modification for Pt with titanium oxide. The fabrication scheme involved the spin-coating of a Ti precursor onto a Pt thin layer that was physically sputtered onto a Si substrate. The whole assembly was subjected to a post-annealing processing to produce the TiOx layer (60 nm) in a porous structure (mostly Anatase) atop of the Pt surface. The porous nature of the TiOx layer permitted the participation of Pt in the electrocatalysis of the …
Tuning The Activity And Stability Of Platinum Nanoparticles Toward The Catalysis Of The Formic Acid Electrooxidation, Islam M. Al-Akraa, Bilquis A. Al-Qodami, Santosh Sridhar Mysore Dr, R. Viswanatha Dr, Abdul Kareem Thottoli, Ahmad M. Mohammad
Tuning The Activity And Stability Of Platinum Nanoparticles Toward The Catalysis Of The Formic Acid Electrooxidation, Islam M. Al-Akraa, Bilquis A. Al-Qodami, Santosh Sridhar Mysore Dr, R. Viswanatha Dr, Abdul Kareem Thottoli, Ahmad M. Mohammad
Chemical Engineering
No abstract provided.
Water-Mediated Peptide Bond Formation In The Gas Phase: A Model Prebiotic Reaction, George C. Shields, Ariel Gale, Tuguldur T. Odbadrakh, Tyler Ball
Water-Mediated Peptide Bond Formation In The Gas Phase: A Model Prebiotic Reaction, George C. Shields, Ariel Gale, Tuguldur T. Odbadrakh, Tyler Ball
Chemistry Publications
The emergence of life on the prebiotic Earth must have involved the formation of polypeptides, yet the polymerization of amino acids is thermodynamically unfavorable under biologically relevant aqueous conditions because amino acids are zwitterions in solution and because of the production of a water molecule through a condensation reaction. Many mechanisms for overcoming this thermodynamic unfavorability have been proposed, but the role of gas phase water clusters has not been investigated. We present the thermodynamics of the water-mediated gas phase dimerization reaction of glycine as a model for the atmospheric polymerization of amino acids prior to the emergence of biological …