Chemistry Commons^™

K-Shell X-Ray Spectroscopy Of Atomic Nitrogen, M. M. Sant'anna, Gunnar Ohrwall, Wayne C. Stolte, Alfred S. Schlachter, Dennis W. Lindle, B. M. Mclaughlin

Chemistry and Biochemistry Faculty Research

Absolute K-shell photoionization cross sections for atomic nitrogen have been obtained from both experiment and state-of-the-art theoretical techniques. Because of the difficulty of creating a target of neutral atomic nitrogen, no high-resolution K-edge spectroscopy measurements have been reported for this important atom. Interplay between theory and experiment enabled identification and characterization of the strong 1s → np resonance features throughout the threshold region. An experimental value of 409.64 ± 0.02 eV was determined for the K-shell binding energy.

Global Variations Of Hdo And Hdo/H2o Ratios In The Upper Troposphere And Lower Stratosphere Derived From Ace-Fts Satellite Measurements, William J. Randel, Elisabeth Moyer, Mijeong Park, Eric Jensen, Peter Bernath

Chemistry & Biochemistry Faculty Publications

High-quality satellite observations of water and deuterated water in the upper troposphere and lower stratosphere (UTLS) from the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) are used to map global climatological behavior. Spatial and temporal variability in these data suggest that convection plays a significant role in setting water vapor isotopic composition in these regions. In many instances, enhancements in HDO/H₂O (i.e., δD) are closely tied to patterns of climatological deep convection and uncorrelated with water vapor, although convection appears to have different isotopic effects in different locations. The ACE-FTS data reveal seasonal variations in the tropics …

National Center For Nuclear Security, Veraun Chipman, Amanda Klingensmith, Cathy Snelson

NSTec UNLV Symposium

National Center for Nuclear Security (NCNS) Mission

•Chartered mission is to enhance the Nation’s verification and detection capabilities in support of nuclear arms control and nonproliferation through R&D activities at the NNSS
•Three focus areas
–Treaty Verification Technologies
–Nonproliferation Technologies
–Technical Nuclear Forensics

Properties Of Cu(In,Ga) Se2 Thin Films And Solar Cells Deposited By Hybrid Process, S. Marsillac, H. Khatri, K. Aryal, R. W. Collins

Electrical & Computer Engineering Faculty Publications

Cu(In,Ga)Se-2 solar cells were fabricated using a hybrid cosputtering/evaporation process, and efficiencies as high as 12.4% were achieved. The films were characterized by energy-dispersive X-ray spectroscopy, glancing incidence X-ray diffraction, scanning electron microscopy, auger electron spectroscopy, and transmittance and reflectance spectroscopy, and their properties were compared to the ones of films deposited by coevaporation. Even though the films were relatively similar, the ones deposited by the hybrid process tend to have smaller grains with a slightly preferred orientation along the (112) axis and a rougher surface. Both types of films have uniform composition through the depth. Characterization of these films …

Water Diffusion In And Out Of The Β-Barrel Of Gfp And The Fast Maturing Fluorescent Protein, Turbogfp, Marc Zimmer, Binsen Li, Ramza Shahid, Paola Peshkepija

Chemistry Faculty Publications

The chromophore of fluorescent proteins is formed by an internal cyclization of the tripeptide 65SYG67 fragment and a subsequent oxidation. The oxidation is slow – the kinetics of this step is presumably improved in fast maturing GFPs. Water molecules can aid in the chromophore formation. We have used 50ns molecular dynamics simulations of the mature and immature forms of avGFP and TurboGFP to examine the diffusion of water molecules in-and-out of the protein β-barrel. Most crystal structures of GFPs have well-structured waters within hydrogen-bonding distance of Glu222 and Arg96. It has been proposed that they have an important role in …

Accessibility And Selective Stabilization Of The Principal Spin States Of Iron By Pyridyl Versus Phenolic Ketimines: Modulation Of The 6A1 ↔ 2T2 Ground-State Transformation Of The [Fen4O2]+ Chromophore, Musa S. Shongwe, Usama A. Al-Zaabi, Faizah Al-Mjeni, Carla S. Eribal, Imaddin A. Al-Omari, Hussein H. Hamdeh, Dariusz Matoga, Harry Adams, Michael J. Morris, Arnold L. Rheingold, Eckhard Bill, David J. Sellmyer

David Sellmyer Publications

Several potentially tridentate pyridyl and phenolic Schiff bases (apRen and HhapRen, respectively) were derived from the condensation reactions of 2-acetylpyridine (ap) and 2′-hydroxyacetophenone (Hhap), respectively, with N-R-ethylenediamine (RNHCH₂CH₂NH₂, Ren; R = H, Me or Et) and com-plexed in situ with iron(II) or iron(III), as dictated by the nature of the ligand donor set, to generate the six-coordinate iron compounds [Fe^II(apRen)₂]X₂ (R = H, Me; X– = ClO4–, BPh4–, PF6–) and [Fe^III(hapRen)₂]X (R = Me, Et; X– = ClO_4–, BPh_4–). Single-crystal X-ray …

Chiral Magnetization Configurations In Magnetic Nanostructures In The Presence Of Dzyaloshinski-Moriya Interactions, Naoise Grisewood, John Eves, Timothy Usher, Hans-Benjamin Braun

Physics Faculty Publications

Many low-dimensional systems, such as nanoscale islands, thin films, and multilayers, as well as bulk systems, such as multiferroics, are characterized by the lack of inversion symmetry, a fact that may give rise to a Dzyaloshinskii-Moriya (DM) interaction. For sufficient strength, the DM interaction will favor spiral spin configurations of definite chirality. In order to harness such systems for applications, it is important to understand the conditions under which these spiral spin configurations form and how they can be controlled via an external field. Here, we present exact solutions of the 1D magnetization profiles in such systems for arbitrary material …

Ua94/6/10 Student / Alumni Personal Papers Wku Carl Ellis, Wku Archives

WKU Archives Collection Inventories

Scientific notebooks used by Carl Ellis during his years at WKU.

Understanding Fracture, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Technical Note: A Trace Gas Climatology Derived From The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (Ace-Fts) Data Set, A. Jones, K. A. Walker, J. J. Jin, J. R. Taylor, C. D. Boone, P. F. Bernath, S. Brohede, G. L. Manney, S. Mcleod, R. Hughes, W. H. Daffer

Chemistry & Biochemistry Faculty Publications

The Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS) aboard the Canadian satellite SCISAT (launched in August 2003) was designed to investigate the composition of the upper troposphere, stratosphere, and mesosphere. ACE-FTS utilizes solar occultation to measure temperature and pressure as well as vertical profiles of over thirty chemical species including O₃, H₂O, CH₄, N₂O, CO, NO, NO₂, N₂O₅, HNO₃, HCl, ClONO₂, CCl₃F, CCl₂F₂, and HF. Global coverage for each species is obtained approximately over a three month …

The Driving Forces Of Change In Energy-Related Co2 Emissions In Ireland: A Multi-Sectoral Decomposition From 1990 To 2007, Tadhg O'Mahony, Peng Zhou, John Sweeney

Articles

Ireland recorded significant growth in energy-related carbon emissions from 1990 to 2007 as the country underwent rapid economic development. Using the LMDI decomposition analysis method, this paper aims to identify and analyse the driving forces of CO2 emissions in eleven final energy consuming sectors. This multi-sectoral analysis is based on four economic sectors, the residential sector and gives a detailed representation of transport in keeping with UNFCCC recommendations. Scale, structure and intensity effects are explored and substantial heterogeneity in sectoral performance is observed. Scale growth in economic and transport activity was considerable. Some improvements in energy intensity were recorded in …

Listen, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Spotlight On Usc: Mechanical Engineering, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Photographic Evidence, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Influencing Art, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

Scas Officers And Council Members 2011 - 2012

Journal of the South Carolina Academy of Science

No abstract provided.

Capturing Motion, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Resonant Inelastic X-Ray Scattering Of Methyl Chloride At The Chlorine K Edge, L. El Khoury, Loic Journel, Renaud Guillemin, Stephane Carniato, Wayne C. Stolte, T. Marin, Dennis W. Lindle, Marc Simon

Chemistry and Biochemistry Faculty Research

We present a combined experimental and theoretical study of isolated CH3Cl molecules using resonant inelastic x-ray scattering (RIXS). The high-resolution spectra allow extraction of information about nuclear dynamics in the core-excited molecule. Polarization-resolved RIXS spectra exhibit linear dichroism in the spin-orbit intensities, a result interpreted as due to chemical environment and singlet-triplet exchange in the molecular core levels. From analysis of the polarization-resolved data, Cl 2px, y and 2pz electronic populations can be determined.

Thomson-Resonant Interference Effects In Elastic X-Ray Scattering Near The Cl K Edge Of Hcl, Stephane Carniato, P. Selles, Loic Journel, Renaud Guillemin, Wayne C. Stolte, L. El Khoury, T. Marin, Faris Gel'mukhanov, Dennis W. Lindle, Marc Simon

Chemistry and Biochemistry Faculty Research

We experimentally observed interference effects in elastic x-ray scattering from gas-phase HCl in the vicinity of the Cl K edge. Comparison to theory identifies these effects as interference effects between non-resonant elastic Thomson scattering and resonant Raman scattering. The results indicate the non-resonant Thomson and resonant Raman contributions are of comparable strength. The measurements also exhibit strong polarization dependence, allowing an easy identification of the resonant and non-resonant contributions.

Compositional Features Of Japanese Humic Substances Society Standard Soil Humic And Fulvic Acids By Fourier Transform Ion Cyclotron Resonance Mass Spectrometry And X-Ray Diffraction Profile Analysis, Kosuke Ikeya, Rachel L. Sleighter, Patrick G. Hatcher, Akira Watanabe

Chemistry & Biochemistry Faculty Publications

The composition of humic acids (HAs) and Fulvic Acids (FAs) from Inogashira (Umbric Andosol) and Dando (Dystric Cambisol) soils authorized as standard samples by the Japanese Humic Substances Society was characterized using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and X-ray diffraction (XRD) 11 band profile analysis. In FTICR-MS, the number of peaks that molecular formulas were assigned to was 2549-2913 for the FAs and 1943-2457 for the HAs. Molecular formulas with H/C and O/C ratios similar to condensed hydrocarbons were dominant in both the HAs, while those with H/C and O/C ratios similar to lignin were more abundant …

First Remote Sensing Observations Of Trifluoromethane (Hfc-23) In The Upper Troposphere And Lower Stratosphere, Jeremy J. Harrison, Christopher D. Boone, Alexander T. Brown, Nicholas D. C. Allen, Geoffrey C. Toon, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

This work reports the first remote sensing measurements of atmospheric HFC-23 (CHF₃) using solar occultation measurements made by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) and the Jet Propulsion Laboratory Mark IV (MkIV) balloon interferometer. A total of 8809 ACE occultations measured between 2004 and 2010 have been processed, along with 24 MkIV occultations measured between 1989 and 2007. ACE data (yearly averages over the 10-25 km altitude range) in the tropics/subtropics (40°S-40°N) reveal a trend of 4.0 ± 1.6% per year in the growth of HFC-23 for 2004-2009 (or 3.9 ± 1.2% per year for 2004-2010), …

Applications Of Density Functional Theory In Materials Science And Engineering, Manuel Alvarado

Open Access Theses & Dissertations

Density Functional Theory (DFT) is a powerful tool that can be used to model various systems in materials science. Our research applies DFT to two problems of interest. First, an organic/inorganic complex dye system known as a Mayan pigment is modeled to determine chemical binding sites, verifying each model with physical data such as UV/Vis spectra. Preliminary studies on palygorskite-based mayan pigments (mayacrom blue, mayacrom purple) show excellent agreement with experimental studies when using a dimer dye geometry binding with tetrahedrally-coordinated aluminum impurity sites in palygorksite. This approach is applied to a sepiolite-based organic/inorganic dye system using thioindigo attached to …

Computational Study Of The Hydration Of Sulfuric Acid Dimers: Implications For Acid Dissociation And Aerosol Formation, Berhane Temelso, Thuong Ngoc Phan, George C. Shields

Faculty Journal Articles

We have investigated the thermodynamics of sulfuric acid dimer hydration using ab initio quantum mechanical methods. For (H₂SO₄)₂(H₂O)_n where n = 0−6, we employed high-level ab initio calculations to locate the most stable minima for each cluster size. The results presented herein yield a detailed understanding of the first deprotonation of sulfuric acid as a function of temperature for a system consisting of two sulfuric acid molecules and up to six waters. At 0 K, a cluster of two sulfuric acid molecules and one water remains undissociated. Addition of a second …

Identification Of The Biogenic Compounds Responsible For Size-Dependent Nanoparticle Growth, Paul M. Winkler, John Ortega, Thomas Karl, Luca Cappellin, Hans R. Friedli, Kelley Barsanti, Peter H. Mcmurry, James N. Smith

Civil and Environmental Engineering Faculty Publications and Presentations

The probability that freshly nucleated nanoparticles can survive to become cloud condensation nuclei is highly sensitive to particle growth rates. Much of the growth of newly formed ambient nanoparticles can be attributed to oxidized organic vapors originating from biogenic precursor gases. In this study we investigated the chemical composition of size-selected biogenic nanoparticles in the size range from 10 to 40 nm. Particles were formed in a flow tube reactor by ozonolysis ofα-pinene and analyzed with a Thermal Desorption Chemical Ionization Mass Spectrometer. While we found similar composition in 10 and 20 nm particles, the relative amounts of …

A New Method To Derive Electronegativity From Resonant Inelastic X-Ray Scattering, Stephane Carniato, Loic Journel, Renaud Guillemin, Maria Novella Piancastelli, Wayne C. Stolte, Dennis W. Lindle, Marc Simon

Chemistry and Biochemistry Faculty Research

Electronegativity is a well-known property of atoms and substituent groups. Because there is no direct way to measure it, establishing a useful scale for electronegativity often entails correlating it to another chemical parameter; a wide variety of methods have been proposed over the past 80 years to do just that. This work reports a new approach that connects electronegativity to a spectroscopic parameter derived from resonant inelastic x-ray scattering. The new method is demonstrated using a series of chlorine-containing compounds, focusing on the Cl 2p−1LUMO1 electronic states reached after Cl 1s→LUMO core excitation and subsequent KL radiative decay. Based on …

Hrc Enews — 2012 Winter, Megan M. Iudice

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.

Volume 04, Matt Szemborski, Phillip Van Ness, Sarah Croughwell, Sarah Mayfield, Alyssa Strackbein, Marley Kimmel, Stephanie Skipp, Jamie Yurasits, Katherine Taggart, Alex Leonhart, Kristen Rawls, Andrew Armes, Amanda Haymens, Allison Paqlowski, Erica May, Stephanie Lane, Luke Acree, Cassandra L. Wilson, Stephanie Pishock, Erica Hopson, K. Juston Osborne, Katheryn Grayson, Kyle Fowlkes, Jessica Cox, Kaity Byrum, John-Harwood Scott, Ashley Johnson, Samantha Hockman, Emily Staskiel, Nancy Macdonald, R. Kruger Bressin, Benjamin P. Bilodeau, Andrea Irby, Kristin Macquarrie, Sarah Bietsch, Elizabeth Bednar

Incite: The Journal of Undergraduate Scholarship

Please note that part of pages 92-95 are redacted, in the digital copy, due to a misprint of the original printed article.

Introduction from Dean Dr. Charles Ross

The Internal Other: Transculturation and Postcolonial Magical Realism in Rushdie’s Midnight’s Children by Matt Szemborski

Photography by Phillip Van Ness

Photography “Waterfall” by Sarah Croughwell

Romancing the Bite: Statistical Analysis of Young Adult Vampire Novels by Sarah Mayfield

Photography by Alyssa Strackbein

Photography by Marley Kimmel

Wine and Society in the Viceroyalty of Peru by Stephanie Skipp

Analysis of Claud Monet’s Impression, Sunrise by Jamie Yurasits

Exploring Meaning: The Lindisfarne Gospels by …

In Situ And Ex Situ Studies Of Molybdenum Thin Films Deposited By Rf And Dc Magnetron Sputtering As A Back Contact For Cigs Solar Cells, K. P. Aryal, H. Khatri, R. W. Collins, S. Marsillac

Electrical & Computer Engineering Faculty Publications

Molybdenum thin films were deposited by rf and dc magnetron sputtering and their properties analyzed with regards to their potential application as a back contact for CIGS solar cells. It is shown that both types of films tend to transition from tensile to compressive strain when the deposition pressure increases, while the conductivity and the grain size decreas. The nucleation of the films characterized by in situ and real time spectroscopic ellipsometry shows that both films follow a Volmer-Weber growth, with a higher surface roughness and lower deposition rate for the rf deposited films. The electronic relaxation time was then …

Magnetic And Orbital Orders Coupled To Negative Thermal Expansion In Mott Insulators, Ca2ru1-Xmxo4 (M = 3d Transition Metal Ion), Tongfei Qi

Theses and Dissertations--Physics and Astronomy

Ca₂RuO₄ is a structurally-driven Mott insulator with a metal-insulator (MI) transition at T_MI = 357K, followed by a well-separated antiferromagnetic order at T_N = 110 K. Slightly substituting Ru with a 3d transition metal ion M effectively shifts T_MI and induces exotic magnetic behavior below T_N. Moreover, M doping for Ru produces negative thermal expansion in Ca₂Ru_1-xM_xO₄ (M = Cr, Mn, Fe or Cu); the lattice volume expands on cooling with a total volume expansion ratio reaching as high as 1%. The onset of the …