Lithium Air Batteries: Non-Aqueous And Hybrid Systems,
2015
College of Engineering and Applied Sciences, and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China;
Lithium Air Batteries: Non-Aqueous And Hybrid Systems, Sheng-Fu Tong, Ping He, Xue-Ping Zhang, Shi-Yong Zhao, Hao-Shen Zhou
Journal of Electrochemistry
Developing energy storage devices and new materials, which match the requirements in electric vehicles (EVs) and hybrid electric vehicles (HEVs), is an effective way to balance the contradiction between the social development and the shortage of fossil energy and environment pollution. Rechargeable lithium-air (Li-air) batteries consisting of Li and oxygen as the anodic and cathodic reactants, respectively, have attracted much attention during the past decade due to their high theoretical specific energy. According to work conditions, the most studied types of Li-air batteries are non-aqueous, hybrid, and solid state electrolyte Li-air batteries. Challenges still exist in cathodes, anodes, electrolytes and …
Pt/C Modified Proton Exchange Membrane For Improved Fuel Cell Performance,
2015
Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
Pt/C Modified Proton Exchange Membrane For Improved Fuel Cell Performance, Zhi Cui, Chao Wang, Shui-Yun Shen, Feng-Jing Jiang, Jun-Liang Zhang
Journal of Electrochemistry
The property of proton exchange membrane greatly affects the performance of proton exchange membrane fuel cells (PEMFC). During the operation of a PEMFC, the water produced at the cathode, the water vapor from the humidified feed gas and the water migrated by electro-dragging will reach a balance in the membrane and determine the resistance of PEMFC, and thus affect the performance of PEMFC. Normally, the PEMFC performance strongly depends on the relative humidity of the feed gas, and the performance decreases at lower humidity as a result of lower proton conductivity of the membrane. In this paper, we proposed to …
Electrolytes For Lithium And Lithium-Ion Batteries,
2015
Department of Chemistry, Shanghai Normal University, Shanghai 200234;
Electrolytes For Lithium And Lithium-Ion Batteries, Zong-Rang Zhang
Journal of Electrochemistry
This is an up-to-date book published by Springer last year and focuses on the field of the electrolytes for lithium and lithium-ion batteries. A brief introduction and review of this book are given in this paper. The main contents of this book are introduced briefly in the order of ten different chapters along with a short review of recent progress in those fields.
The Electronic Structure Of The Pyranopterin Dithiolene Cofactor And Radical Reporters Of Excited State Interactions,
2015
University of New Mexico
The Electronic Structure Of The Pyranopterin Dithiolene Cofactor And Radical Reporters Of Excited State Interactions, Benjamin William Stein
Chemistry and Chemical Biology ETDs
Crystal structures of multiple molybdenum enzymes clearly demonstrate interesting structural distortions involving the pyranopterin dithiolene. These distortions can be correlated with pyranopterin oxidation state through the use of DFT geometry optimized structures of the possible oxidation states, and these are correlated with enzyme family. The potential role of the pyranopterin dithiolene in electron transfer in the varied enzyme familes has been explored through the use of non-equilibrium Green's function (NEGF) electron transport calculations. These calculations demonstrate clear differences in electron transport behavior as a function of pyranopterin oxidation state. The Jahn-Teller effect can strongly impact the geometric and electronic structures …
Electrochemical Investigation Of Homogenous Species At An Electrode Interface,
2015
University of New Mexico
Electrochemical Investigation Of Homogenous Species At An Electrode Interface, Christopher Alan Larsen Iii
Chemistry and Chemical Biology ETDs
CO2 reduction is a pressing problem worldwide, and one obstacle in the electrochemical conversion of CO2 to more useful C1 products such as methanol and formic acid is the kinetic barrier known as overpotential. The overpotential of rearranging the nuclei in CO2 to accommodate electron transfer can be lowered by pre-bending the CO2 molecule in an adduct-mediated complex. The work presented in Part I utilizes a combination of hard and soft donors on pincer-like ligands to effect the bending of CO2 prior to electrochemical reduction. A large majority of the work consists of using …
Theory, Multiscale Simulations, And Experiments On Mesoscale Multifunctional Systems,
2015
University of New Mexico
Theory, Multiscale Simulations, And Experiments On Mesoscale Multifunctional Systems, Lance Edward Edens
Chemistry and Chemical Biology ETDs
Computational simulations use theoretical models to reproduce, as accurately as possible, the observed real-world behavior of complex structures. Guided by experimental observations, many multiscale/coarse-grained simulations seek to explore increasingly complicated systems. Here, a multiscale/coarse-grained simulation program (called TM2) is developed with applications to 1) properties and mechanisms of DNA and DNA polymerases, and 2) adhesion between whole bacterial cells and patterned surfaces. Results from the bacterial adhesion application form a part of a larger collaborative effort aimed at creating multifunctional, controllable surfaces to capture and kill pathogenic bacteria. The application of TM2 is first demonstrated by a coarse-grained model for …
Spectroscopic And Computational Studies Of Molybdenum Enzymes And Models,
2015
University of New Mexico
Spectroscopic And Computational Studies Of Molybdenum Enzymes And Models, Chao Dong
Chemistry and Chemical Biology ETDs
In this dissertation spectroscopic methods such as electronic absorption (EAS), resonance Raman (rRaman), electron paramagnetic resonance (EPR), and MCD spectroscopies have been used in combination with DFT calculations for the interpretation of experimental results. These methods have been used to investigate the molybdenum coordination environment in enzymes and model complexes. Xanthine oxidase (XO), one of the canonical molybdenum enzyme families, hydroxylizes heterocyclic substrates by inserting an oxygen atom from molybdenum-activated water into a substrate C-H bond. This generates reducing equivalents that pass through two iron sulfur clusters and then to FAD, where oxidation of the FAD takes place. In this …
Study Of Novel Synthetic Methodologies For Indolyl Derivatives And Beta-Fluoroenals,
2015
University of New Mexico
Study Of Novel Synthetic Methodologies For Indolyl Derivatives And Beta-Fluoroenals, Xiaobei Chen
Chemistry and Chemical Biology ETDs
One of the central goals in modern organic synthesis is to develop efficient synthetic strategies for the preparation and study of complex molecules possessing interesting structural, biological, and physical properties. Toward this end, my Ph. D. work focuses on the development of novel synthetic methodologies for the facile construction of synthetically and biologically significant molecular architectures. The tert-prenylated indoles and indolines are widely present in a large collection of natural products and biologically active compounds. Although significant efforts have been made on the development of efficient methods to prepare these intriguing molecular architectures, few methods have been explored to introduce …
Corrosion Protection Of 304 Stainless Steel With Melting Gels Coatings,
2015
Instituto de Cerámica y Vidrio
Corrosion Protection Of 304 Stainless Steel With Melting Gels Coatings, Mario Aparicio, Andrei Jitianu, Gabriela Rodriguez, Ahmad Dengah, Kutaiba Marzoki, Jadra Mosa, Lisa C. Klein
Publications and Research
Methyl-substituted melting gels were used to coat AISI 304 stainless steel substrates. Crack-free coatings up to 1 mm in thickness were obtained. SEM micrographs of cross-sections con fi rm good adhesion to the surface. Samples were subjected to structural characterization using FT-IR, and Raman spectroscopy. Mechanical properties were investigated by micro-scratch tests. Electrochemical analyses (anodic polarization and electrochemical impedance spectroscopy) were performed in 3.5% NaCl solutions. Electrochemical tests show excellent performance of the coatings against corrosion with no sign of degradation after several months of immersion.
Simulation Of Energetic Particle Precipitation Effects During The 2003-2004 Arctic Winter,
2015
Old Dominion University
Simulation Of Energetic Particle Precipitation Effects During The 2003-2004 Arctic Winter, C. E. Randall, V. L. Harvey, L. A. Holt, D. R. Marsh, D. Kinnison, B. Funke, P. F. Bernath
Chemistry & Biochemistry Faculty Publications
Energetic particle precipitation (EPP) during the 2003-2004 Arctic winter led to the production and subsequent transport of reactive odd nitrogen (NOx=NO+NO2) from the mesosphere and lower thermosphere (MLT) into the stratosphere. This caused NOx enhancements in the polar upper stratosphere in April 2004 that were unprecedented in the satellite record. Simulations of the 2003-2004 Arctic winter with the Whole Atmosphere Community Climate Model using Specified Dynamics (SD-WACCM) are compared to satellite measurements to assess our understanding of the observed NOx enhancements. The comparisons show that SD-WACCM clearly displays the descent of NOx produced …
Growth In Stratospheric Chlorine From Short-Lived Chemicals Not Controlled By The Montreal Protocol,
2015
Old Dominion University
Growth In Stratospheric Chlorine From Short-Lived Chemicals Not Controlled By The Montreal Protocol, R. Hossaoni, M. P. Chipperfield, A. Saiz-Lopez, J. J. Harrison, R. Von Glasow, R. Sommariva, E. Atlas, M. Navarro, S. A. Montzka, W. Feng, P. F. Bernath
Chemistry & Biochemistry Faculty Publications
We have developed a chemical mechanism describing the tropospheric degradation of chlorine containing very short-lived substances (VSLS). The scheme was included in a global atmospheric model and used to quantify the stratospheric injection of chlorine from anthropogenic VSLS (ClyVSLS) between 2005 and 2013. By constraining the model with surface measurements of chloroform (CHCl3), dichloromethane (CH2Cl2), tetrachloroethene (C2Cl4), trichloroethene (C2HCl3), and 1,2-dichloroethane (CH2ClCH2Cl), we infer a 2013 ClyVSLS mixing ratio of 123 parts per trillion (ppt). Stratospheric injection …
Titanium Trisulfide Monolayer: Theoretical Prediction Of A New Direct-Gap Semiconductor With High And Anisotropic Carrier Mobility,
2015
University of Nebraska-Lincoln
Titanium Trisulfide Monolayer: Theoretical Prediction Of A New Direct-Gap Semiconductor With High And Anisotropic Carrier Mobility, Jun Dai, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
A new two-dimensional (2D) layered material, namely, titanium trisulfide (TiS3) monolayer, is predicted to possess novel electronic properties. Ab initio calculations show that the perfect TiS3 monolayer is a direct-gap semiconductor with a bandgap of 1.02 eV, close to that of bulk silicon, and with high carrier mobility. More remarkably, the in-plane electron mobility of the 2D TiS3 is highly anisotropic, amounting to about 10,000 cm2 V−1 s−1 in the b direction, which is higher than that of the MoS2 monolayer, whereas the hole mobility is about two orders of magnitude lower. …
The Investigation Of The Low Temperature Combustion Of Mesitylene And Tert-Amyl Methyl Ether By Synchrotron Photoionization Mass Spectrometry,
2015
The University of San Francisco
The Investigation Of The Low Temperature Combustion Of Mesitylene And Tert-Amyl Methyl Ether By Synchrotron Photoionization Mass Spectrometry, Martin Yu-Hin Ng
Master's Theses
This thesis describes the combustion experiments performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) located at the Lawrence Berkeley National Laboratories (LBNL). The need for renewable fuel sources, the need for the study of their combustion in the contexts of homogenous charge combustion ignition (HCCI) engines can be found in Chapter 1. The components of the experimental set-up used throughout this thesis—time-of-flight mass spectrometer, Excimer laser, vacuum pumps and other components—and the components of ALS responsible in synchrotron radiation generation and processing—the linear accelerator, the booster ring, insertion devices, gas filters and monochromator are explained in …
Diol-Mediated Versus Water-Mediated Proton Transfer Reactions,
2015
DePaul University
Diol-Mediated Versus Water-Mediated Proton Transfer Reactions, Angela Moses
DePaul Discoveries
The triple-proton-transfer reactions of 8H-1,8-naphthyridin-2-one (8H-naph) have been investigated by employing different ab initio quantum mechanical methods. The proton transfer reactions studied were facilitated through an adjacent 1,3-propanediol molecule or two adjacent water molecules. Identical proton transfer reactions were studied using a model system of 8H-naph to investigate the validity of computational approaches that use model systems to study more complex systems. The solvent effects on the structures were investigated for comparison to the initial gas phase calculations. The potential energy, reaction force, and work profiles were studied along the intrinsic reaction coordinate to monitor the developing proton transfer reactions.
Furanic Molecules: Multiplexed Synchrotron Photoionization Investigations And Aerosol Studies,
2015
University of San Francisco
Furanic Molecules: Multiplexed Synchrotron Photoionization Investigations And Aerosol Studies, Audrey R. Smith
Master's Theses
The oxidation reactions of 2-methylfuran (2MF) and 2-ethylfuran (2EF) initiated by Cl radicals is studied at the low temperatures, in addition to the determination of the absolute photoionization cross-sections of 2EF, 2-acetylfuran, and furfural. These experiments are carried out using synchrotron photoionization mass spectrometry (SPIMS) with an orthogonal time-of-flight spectrometer used for mass analysis at the Advanced Light Source of Lawrence Berkeley National Laboratory. CBS-QB3 calculated adiabatic ionization energies (AIE) agree well with the experimental results and published literature values. Furfural is found to be the dominant product of 2MF oxidation, with 2-acetylfuran and 2-vinylfuran being the dominant products of …
Effects Of Anions And Amino Acids On Surface Tension Of Water,
2015
James Madison University
Effects Of Anions And Amino Acids On Surface Tension Of Water, Diana Al Husseini
Senior Honors Projects, 2010-2019
Hofmeister series is a set of ions in order of their abilities to affect physical properties in aqueous solutions. Franz Hofmeister was the first to discover the specific ion effects on protein solubility in aqueous solutions. Although the Hofmeister phenomena are general, their mechanisms are still not fully understood. Herein, we use optical tensiometry by a pendant drop method to study the Hofmeister anion effects on the surface tension of water. It has been observed that the surface tension of water increases linearly as the salt concentrations increase. The effects of salts follow a specific trend with respect to the …
Corrosion Behaviors Of Coated Aluminum Alloys In Simulated Corrosive Environment,
2015
Western Kentucky University
Corrosion Behaviors Of Coated Aluminum Alloys In Simulated Corrosive Environment, Jingyi Yue
Masters Theses & Specialist Projects
This study investigated the corrosion of an aluminum alloy with and without coatings under simulated corrosive environments. Coatings were selected and applied from commercial materials and techniques, consisting of microceramic, epoxy primer, and topcoat. The experiments for coated specimens were carried out under various corrosive conditions, specifically, hydrodynamic flow, immersion in salt water and DI water, varying temperatures, and simulated sun light. The hydrodynamic conditions were simulated using a rotating cylinder electrode (RCE) with rotational speeds of 200, 400, 600, 800, and 1000 rpm. The immersion in saltwater and sunlight illumination tests were applied for 8 hours, and the simulated …
Chemically Accurate Calculations Of Rate Constants Of Spin Trap-Hydroxyl Radical Addition Reactions,
2015
East Tennessee State University
Chemically Accurate Calculations Of Rate Constants Of Spin Trap-Hydroxyl Radical Addition Reactions, Hayden B. Short
Undergraduate Honors Theses
The DMPO type spin trap 5,5-Dimethyl-1-pyrroline N-oxide (DMPO) and the exceptionally similar spin trap 2-ethoxycarbonyl-2-methyl-3,4-dihydro-2H-pyrrole-l-oxide (EMPO) are widely studied in computational and theoretical works. This particular study examines the addition reactions that both these molecules undergo with the carcinogenic hydroxyl radical. This work used a relatively new approximation method, called the correlation consistent composite approach or ccCA, for carrying out quantum mechanical calculations to give the free energies of the products and reactants of the reactions. The free energies are to be used to extrapolate the rate constants of the reactions from the Arrhenius equation. Though both the spin traps …
Syntheses, Structures And Properties Of Metal-Organic Frameworks,
2015
Western Kentucky University
Syntheses, Structures And Properties Of Metal-Organic Frameworks, Xin Liu
Masters Theses & Specialist Projects
Mercury is one of the most serious heavy metal pollution sources that threaten people’s health. For decades, people have developed many technologies and materials to capture mercury from flue gas of coal-fired plant. Currently, the most effective material for mercury absorption is powdered activated carbon, which shows increased efficiency when modified with halogen functional groups such as bromine. Metal-organic frameworks (MOFs) have potential applications in mercury capture due to their fantastic properties such as high porosity and high thermal stability. More important, their pore sizes and topology structures can be controlled through choosing different organic ligands in the syntheses. However, …
Green Chemistry As A Tool For Understanding The Toxic Substances Control Act: A Lecture Module For Undergraduate Students,
2015
University of Connecticut - Storrs
Green Chemistry As A Tool For Understanding The Toxic Substances Control Act: A Lecture Module For Undergraduate Students, Molly R. Blessing
Honors Scholar Theses
The Toxic Substances Control Act (TSCA) is the central form of chemical regulation existent in the United States today, yet scientists are often unaware or uncertain of its provisions. Violations of TSCA by unknowing chemists set industry and government unnecessarily at odds. A lecture on TSCA was developed for undergraduate students that uses the concept of green chemistry to promote interest and incentivize learning. Green chemistry methods are cleaner and less wasteful than traditional chemical ones, and many companies using them are at the forefront of technological innovation. The lecture explains both green chemistry and TSCA, includes company case studies, …
