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Synthesis And Electrochemical Behaviors Of Li2Coxmn1-XSio4 As A Cathode Material For Lithium-Ion Batteries, Lin WANG, Dong-ping LV, Yong YANG 2011 State Key Laboratory of Physical Chemistry of Solid Surfaces , College ofChemistry and ChemicalEngineering,Xiamen University, Xiamen 361005,Fujian, China

Synthesis And Electrochemical Behaviors Of Li2Coxmn1-XSio4 As A Cathode Material For Lithium-Ion Batteries, Lin Wang, Dong-Ping Lv, Yong Yang

Journal of Electrochemistry

We have successfully synthesized Li2CoxMn1-xSiO4/C (x=0, 0.1, 0.3, 0.5, 1)/C composites using hydrothermal assisted sol-gel process and ball-milling method. The results of X-ray diffraction show that the solid solutions of Li2CoxMn1-xSiO4 can be achieved when x≤0.3. The initial capacities increase from 70 mAh·g-1 of Li2MnSiO4/C to 105 mAh·g-1 of Li2Co0.3Mn0.7SiO4/C. Cyclic Voltammetry (CV) curves show that the replacement of Mn with Co can reduce the electrochemical polarization, making the insertion-extraction reaction …


Corrosion Characteristics Of Galvanized Flat Steel For Power Grounding In Nacl Solution Medium, Yong LI, Gao-Lin WU, Bang-Fei DENG, Ping YANG, Xue-Ming LI, Qing-Bin ZONG 2011 1.Chongqing Electric Power & Research Institute, Chongqing 401123, China;

Corrosion Characteristics Of Galvanized Flat Steel For Power Grounding In Nacl Solution Medium, Yong Li, Gao-Lin Wu, Bang-Fei Deng, Ping Yang, Xue-Ming Li, Qing-Bin Zong

Journal of Electrochemistry

The corrosion behavior of power grounding galvanized flat steel was studied by polarization measurement, electrochemical impedance spectroscopy and neutral salt spray test in 5% NaCl solutions. The surface morphologies of galvanized coating and structural properties of corrosion products were observed with scanning electron microscope and X-ray diffraction spectrometer, respectively. Results showed that under the temperatures of 20~60℃, the corrosion currents of galvanized flat steel increased with the temperature rising. The corrosion rate at 60℃ was 0.8408 mA·cm-2, which is 2.9 times larger than that at 20℃. The corrosion rate dropped after reaching the maximal value of 1.95 mg·cm …


Electrelectrochemical Performances Of C-Coating And Co-Doping Lifepo4, Ying BAI, Jue-Ming YANG, Chun-Bo QING, Wei-Feng ZHANG 2011 Key Laboratory of Photovoltaic Materials of Henan Province and School of Physics & Electronics, Henan University,Kaifeng 475004, Henan, China

Electrelectrochemical Performances Of C-Coating And Co-Doping Lifepo4, Ying Bai, Jue-Ming Yang, Chun-Bo Qing, Wei-Feng Zhang

Journal of Electrochemistry

Phospho-olivine LiFePO4 cathode materials were prepared by hydrothermal reaction at 200 oC. Sucrose was added as C-coating resource and Co was doped into the crystal lattice of LiFePO4. In order to investigate the improvements in the electrochemical properties of Co-doped LiFePO4, three samples, LiFePO4, C-coated LiFePO4 and C-coating-Co-doped LiFePO4, were synthesized under the same preparation conditions. Charge/discharge studies reveal that the Co-doped LiFePO4/C composite annealed at 400 oC exhibits marked improvement of specific capacity by diminishing the particle sizes and enhancement in the degree of crystallinity. …


Simultaneous Determination Of Dopamine(Da)And Epinephrine (Ep) At Ca/Gc Electrode, Wang REN, Ying ZHANG, Min-Jiao LI 2011 College of Chemical & Pharmaceutical Engineering, Sichuan University of Seience& Engineering, Zigong 643000, Sichuan, China

Simultaneous Determination Of Dopamine(Da)And Epinephrine (Ep) At Ca/Gc Electrode, Wang Ren, Ying Zhang, Min-Jiao Li

Journal of Electrochemistry

The citric acid modified glassy carbon electrode (CA/GC) was prepared by potentiostatic technique and was used for detections of dopamine (DA), epinephrine (EP), and their mixtures by differential pulse voltammetry (DPV). The modified electrode shows the enhanced sensitivity and excellent electrochemical discrimination to DA and EP. The cathodic potential difference between DA and EP was about 380 mV, while no cathodic reduction of ascorbic acid (AA) was observed because the oxidation of AA is an irreversible reaction at the sensor. As a result, DA and EP could be determined simultaneously with the interferences of high concentrations of AA being eliminated. …


Applied Study Of Electrochemical Potentiokinetic Reactivation Method, Xiao-Qin ZHA, Jian LIANG, Xin-Yao ZHANG, Ya-Jun ZHANG, Li-Juan ZHANG 2011 Luoyang Ship Material Research Institute, Luoyang 471039, Henan, China

Applied Study Of Electrochemical Potentiokinetic Reactivation Method, Xiao-Qin Zha, Jian Liang, Xin-Yao Zhang, Ya-Jun Zhang, Li-Juan Zhang

Journal of Electrochemistry

The susceptibility to intergranular corrosion of overlay welding stainless steel composite plate (00Cr17Ni14Mo2) and low-Cr ferritic stainless steel (06Cr13R) was studied by electrochemical potentiokinetic reactivation (EPR) method. The results indicated that the ratio of the maximum current Ir/Ia generated by the reactivation EPR scan to that of the anodic scan is appropriate for evaluating the intergranular corrosion of 00Cr17Ni14Mo2, which is consistent with the H2SO4-CuSO4-Cu method, and also appropriate for evaluating the intergranular corrosion of 06Cr13R, which is consistent with the oxalic acid test method. It shows that the EPR method can be applied …


Mechanistic Studies On Xanthine Oxidoreductase Enzymes, Abebe Berhane 2011 University of New Mexico

Mechanistic Studies On Xanthine Oxidoreductase Enzymes, Abebe Berhane

Chemistry and Chemical Biology ETDs

In humans, the xanthine oxidoreductase enzymes are known to catalyze the final two steps of purine metabolism by converting hypoxanthine successively to xanthine and uric acid. Xanthine oxidoreductase also metabolizes a wide variety of drugs in vivo, and activates a number of antiviral prodrugs of clinical importance. Therefore, understanding the reaction mechanism of this enzyme is of prime importance in furthering our understanding of enzyme-drug interactions. In order to provide a greater understanding on the reaction mechanism, theoretical and enzymatic spectroscopic experimental approaches have been utilized. The theoretical approaches were used to elucidate the electronic structure and geometry of the …


Neutron Diffraction Of Nabd4: Phase Transition, Rietveld Structure Refinements, And Equation Of State, Guillermo Esparza, Esparza, Patricia Kalita, Andrew Cornelius 2011 Harvey Mudd College

Neutron Diffraction Of Nabd4: Phase Transition, Rietveld Structure Refinements, And Equation Of State, Guillermo Esparza, Esparza, Patricia Kalita, Andrew Cornelius

Undergraduate Research Opportunities Program (UROP)

NaBH4 is a hydride with possible applications as a hydrogen storage material for future renewable energy technologies. It’s dehydrogenation properties are enhanced with the mixture of particular catalysts through ball-milling techniques during which local pressures may exceed several GPa’s. It is for this reason that understanding the behavior of pressure induced phase changes of its crystalline unit cell is an area of interest.


Characterization Of Uranium Species In Sediments Under Iron And Sulfate Reducing Conditions Using Synchrotron-Based Techniques, Don Q. Pham, John Bargar 2011 San Jose State University

Characterization Of Uranium Species In Sediments Under Iron And Sulfate Reducing Conditions Using Synchrotron-Based Techniques, Don Q. Pham, John Bargar

STAR Program Research Presentations

Uranium is one of the most common and problematic contaminants at legacy Department of Energy sites. Groundwater contamination is particularly problematic because it occurs at depth, is present in large volumes, and cannot be easily accessed for clean-up. One method of remediation being investigated is the bioreduction of soluble U(VI) to insoluble U(IV) complexes through the in-situ stimulation of metal-reducing bacteria. Understanding the structure of these uranium complexes can help us determine their fate and stability in groundwater and map out the biological process of uranium reduction by metal-reducing bacteria. In this study, we used the synchrotron-based techniques, X-ray absorption …


Exploring Methods For Earthquake Prediction: The Effects Of Water On The Flow Of Stress-Activated Electric Currents In Igneous Rocks, Aaron M. Jahoda, Friedemann T. Freund 2011 California Polytechnic State University - San Luis Obispo

Exploring Methods For Earthquake Prediction: The Effects Of Water On The Flow Of Stress-Activated Electric Currents In Igneous Rocks, Aaron M. Jahoda, Friedemann T. Freund

STAR Program Research Presentations

Much of the devastation and damage of earthquakes can be attributed to the fact that they occur suddenly and without much warning, which limits the ability of people to evacuate and/or properly prepare. One method, however, that might be used to predict seismic events is the generation of electric currents in rocks when stresses are applied. It is observed in this research that the application of direct force onto samples of igneous rock causes the rocks to generate a measurable current, which is attributed to positive-hole charges moving within the oxygen sub-lattice. Because large and changing forces are acted upon …


Synthesis, Extraction, Dissolution, And Voltammetry Of F-Species In A Room Temperature Ionic Liquid Solvent, Wendy Jacqueline Pemberton 2011 University of Nevada, Las Vegas

Synthesis, Extraction, Dissolution, And Voltammetry Of F-Species In A Room Temperature Ionic Liquid Solvent, Wendy Jacqueline Pemberton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Room temperature ionic liquids (RTILs) are salts that are liquids from as low as -96 °C to up to 100 °C. RTILs are of high interest in many fields of study because of their negligible vapor pressure, high electrochemical stability, high conductivity, and wide electrochemical windows. These diverse solvents have recently been used in organic synthesis, as extraction solvents, and as electrochemical solvents. It is as a direct result of the multifunctional capabilities of these RTIL solvents that they are examined in this work. The ability to probe the chemistry of lanthanides and actinides is based on the unique properties …


Equilibrium Speciation Of Select Lanthanides In The Presence Of Acidic Ligands In Homo- And Heterogeneous Solutions, Troy Robinson 2011 University of Nevada, Las Vegas

Equilibrium Speciation Of Select Lanthanides In The Presence Of Acidic Ligands In Homo- And Heterogeneous Solutions, Troy Robinson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation explores lanthanide speciation in liquid solution systems related to separation schemes involving the acidic ligands: bis(2-ethylhexyl) phosphoric acid (HDEHP), lactate, and 8-hydroxyquinoline. Equilibrium speciation of neodymium (Nd3+ ), sodium (Na+ ), HDEHP, water, and lactate in the TALSPEAK liquid-liquid extraction system was explored under varied Nd3+ loading of HDEHP in the organic phase and through extraction from aqueous HCl and lactate media. System speciation was probed through vapor pressure osmometry, visible and Fourier Transform Infrared (FTIR) spectroscopy, 22 Na and 13 C labeled lactate radiotracer distribution measurements, Karl Fischer titrations, and equilibrium pH measurements. Distribution …


A Theoretical Investigation Examining Dna Conformational Changes And Their Effects On Glycosylase Function, Allyn Brice 2011 Clemson University

A Theoretical Investigation Examining Dna Conformational Changes And Their Effects On Glycosylase Function, Allyn Brice

All Dissertations

Glycosylase enzymes initiate the process of base excision repair (BER) in order to prevent the irreversible modification of the genome. In the BER process a damaged DNA base is recognized, removed from the DNA sequence, and then the remaining abasic site is repaired. Glycosylase enzymes are responsible for the base recognition mechanism and catalysis of the base excision. One of the most studied glycosylase superfamilies is uracil DNA glycosylase (UDG). The UDG superfamily has demonstrated specificity for excising uracil, which is the deamination product of cytosine, from DNA sequences of prokaryotes and eukaryotes. Mismatch-specific uracil DNA glycosylase (MUG) is a …


Probing Morphology-Dependent Aggregation And Photocurrent Generation In Polymer/Fullerene Photovoltaic Devices, Yongqian Gao 2011 University of New Mexico

Probing Morphology-Dependent Aggregation And Photocurrent Generation In Polymer/Fullerene Photovoltaic Devices, Yongqian Gao

Chemistry and Chemical Biology ETDs

In this dissertation, new spectroscopic and electrical imaging approaches were developed to map morphology-dependent aggregation properties of polymer chains in model solar cell devices. These techniques reveal new correlations between local structure and material performance on sub-micron size scales which are not accessible by other techniques. Resonance Raman spectroscopic imaging was developed as a physical probe to identify and spatially map morphology-dependent variations of intra- and interchain interactions and order in poly-3-hexylthiophene (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) photovoltaic blend thin films. The C=C band of P3HT backbone was decomposed into aggregated and unaggregated component contribution at ~1450 cm …


Quantitative Structure-Property Relationships For Predicting Chlorine Demand And Disinfection Byproducts Formation In Drinking Water, Gebhard Balthazar Luilo 2011 University of New Mexico

Quantitative Structure-Property Relationships For Predicting Chlorine Demand And Disinfection Byproducts Formation In Drinking Water, Gebhard Balthazar Luilo

Chemistry and Chemical Biology ETDs

Models are important tools for designing or redesigning water treatment processes and technologies to minimize disinfection byproducts (DBPs) formation without compromising disinfection efficiency. Empirical models, which are the most common, are based on bulk water quality parameters that vary with time and space. These parameters may not always have linear relationships with chlorine demand and DBPs formation which make structure-based models more attractive to study. In this dissertation, Quantitative Structure-Property Relationship (QSPR) models which make use of structural properties of individual molecules were developed using experimental data obtained from the literature. The amounts are reported in moles of chlorine (HOCl) …


Spectroscopic And Electronic Structure Studies Of Metalloenzyme Active Sites, Joseph Sempombe 2011 University of New Mexico

Spectroscopic And Electronic Structure Studies Of Metalloenzyme Active Sites, Joseph Sempombe

Chemistry and Chemical Biology ETDs

This work reports on the electronic and geometric structural studies of xanthine oxidoreductase (XO), S-ribosylhomocysteinase (LuxS) and inducible nitric oxide synthase (iNOS) active sites resulting from the joint applications of electronic absorption, electron paramagnetic resonance and magnetic circular dichroism spectroscopic methods. XO catalyzes formal oxygen atom insertion into a substrate C-H bond, but differs from monooxygenase enzymes in that the inserted oxygen atom derives from metal activated water and reducing equivalents are generated rather than consumed. Studies on aldehyde inhibited' XO (a paramagnetic form observed during XO catalysis), analyzed in terms of the relationships between the g-, 95,97Mo hyperfine, …


Spectroscopic And Electronic Structure Studies Of Bis-Metallodithiolenes, Regina Peter Mtei 2011 University of New Mexico

Spectroscopic And Electronic Structure Studies Of Bis-Metallodithiolenes, Regina Peter Mtei

Chemistry and Chemical Biology ETDs

Dimethylsulfoxide reductase (DMSOR) enzyme family members catalyze oxygen atom transfer to or from organic or inorganic substrate and play important roles in the global cycles of sulfur and nitrogen, as well as the detoxification of arsenite. This enzyme has recently been subject of investigation due to its catalytic nature of oxygen atom transfer. This work reports on the electronic structure and reactivity properties of dimethylsulfoxide reductase enzyme studied using spectroscopic and computational methods. The spectroscopic methods included electronic absorption (EA), electron paramagnetic resonance (EPR), magnetic circular dichroism (MCD) and resonance Raman rRaman). Here, we report full characterization of the DMSOR …


Application Of Raman Spectroscopy To Lubricants, Lubricated Surfaces And Lubrication Phenomena, David W. Johnson 2011 University of Dayton

Application Of Raman Spectroscopy To Lubricants, Lubricated Surfaces And Lubrication Phenomena, David W. Johnson

Chemistry Faculty Publications

Recent advances in lasers and detector technologies and the development of low-cost instruments and fiber-optic probes have brought about an explosion in the lubrication systems being studied by Raman spectroscopy. This article provides examples of the use of Raman spectroscopy in the study of lubrication phenomena, including the characterization of liquid lubricants, lubricant additives, and solid lubricants; the study of vapor-phase lubrication; and the use of coated nanoparticles as lubricants.


Antibacterial Activity Of Conjugated Electrolytes, Thomas S. Corbitt 2011 University of New Mexico

Antibacterial Activity Of Conjugated Electrolytes, Thomas S. Corbitt

Chemistry and Chemical Biology ETDs

A series of water soluble, cationic, anionic and zwitterionic conjugated polyelectrolytes (CPEs) with main chains based on an arylene ethynylene repeat unit structure with tetraalkylammonium and/or alkylsulfonate side groups were found to exhibit significant antibacterial activity. A number of these complexes also showed pronounced light-induced modulation of their effectiveness, with either biocidal enhancement or suppression, depending on such properties as singlet oxygen sensitization potential and lipophilicity. These collected studies examine the biocidal activity of the CPEs, as determined by Confocal Laser Scanning Microscopy (CLSM) and Flow Cytometry, correlating this activity with the photophysical properties of the polymers. We demonstrate biocidal …


Maxwell's Equations, Part Ii, David W. Ball 2011 Cleveland State University

Maxwell's Equations, Part Ii, David W. Ball

Chemistry Faculty Publications

This is the second part of a multi-part production on Maxwell’s equations of electromagnetism. The ultimate goal is a definitive explanation of these four equations; readers will be left to judge how definitive it is. A note: for certain reasons, figures are being numbered sequentially throughout this series, which is why the first figure in this column is numbered 8. I hope this does not cause confusion. Another note: this is going to get a bit mathematical. It can’t be helped: models of the physical universe, like Newton’s second law F = ma, are based in math. So are Maxwell’s …


Electrochemistry Of Technetium Analogues Rhenium And Molybdenum In Room Temperature Ionic Liquid, Pauline Nancy Serrano 2011 University of Nevada, Las Vegas

Electrochemistry Of Technetium Analogues Rhenium And Molybdenum In Room Temperature Ionic Liquid, Pauline Nancy Serrano

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rhenium was used as an analog for Technetium to study the electrochemical redox properties because the two elements share the same stable oxidation states in aqueous solutions. However, Tc-99 is radioactive and is not readily available for experimentation purposes. Molybdenum is also of interest because when Mo-99 is irradiated, the decay products are Tc-99m and Tc-99. Approximately 30% Tc-99m is eluted from the Mo columns for radiopharmaceutical use with the remaining Mo-99 source decaying to Tc-99 which is discarded as radioactive hospital waste. Currently there are no viable procedures for the reclamation of the radioactive Tc-99 from either fission streams …


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