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2010

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Articles 451 - 480 of 952

Full-Text Articles in Chemistry

Microscopic And Spectroscopic Studies Of Thermally Enhanced Electrospun Pmma Micro- And Nanofibers, Sean Pelfrey, Travis Cantu, Michael R. Papantonakis, Duane L. Simonson, R. Andrew Mcgill, Javier Macossay-Torres Mar 2010

Microscopic And Spectroscopic Studies Of Thermally Enhanced Electrospun Pmma Micro- And Nanofibers, Sean Pelfrey, Travis Cantu, Michael R. Papantonakis, Duane L. Simonson, R. Andrew Mcgill, Javier Macossay-Torres

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Carbon nanofibers (CNFs) have been incorporated into poly(methyl methacrylate) (PMMA) through electrospinning. The resulting micro- and nanofibers have been characterized by Scanning Electron Microscopy (SEM), which confirmed fiber formation and demonstrated a core-sheath structure of the PMMA fibers. Thermogravimetric Analysis (TGA) was used to obtain the thermal properties of the materials, indicating an enhancement in the thermal properties of the composite fibers. In addition, Fourier Transform Infrared Spectroscopy (FTIR) was utilized to investigate the interactions of PMMA micro- and nanofibers with CNFs, demonstrating the preferred sites of intermolecular interactions between the polymer matrix and the filler.


Intermolecular Dehydrative Coupling Reaction Of Arylketones With Cyclic Alkenes Catalyzed By A Well-Defined Cationic Ruthenium-Hydride Complex: A Novel Ketone Olefination Method Via Vinyl C–H Bond Activation, Chae S. Yi, Do W. Lee Mar 2010

Intermolecular Dehydrative Coupling Reaction Of Arylketones With Cyclic Alkenes Catalyzed By A Well-Defined Cationic Ruthenium-Hydride Complex: A Novel Ketone Olefination Method Via Vinyl C–H Bond Activation, Chae S. Yi, Do W. Lee

Chemistry Faculty Research and Publications

The cationic ruthenium−hydride complex [(η6-C6H6)(PCy3)(CO)RuH]+BF4 was found to be a highly effective catalyst for the intermolecular olefination reaction of aryl ketones with cycloalkenes. The preliminary mechanistic analysis revealed that an electrophilic ruthenium−vinyl complex is the key species for mediating both vinyl C−H bond activation and the dehydrative olefination steps of the coupling reaction.


Selective Regulation Of Aromatase Expression For Drug Discovery, Robert W. Brueggemeier, Bin Su, Michael V. Darby, Yasuro Sugimoto Feb 2010

Selective Regulation Of Aromatase Expression For Drug Discovery, Robert W. Brueggemeier, Bin Su, Michael V. Darby, Yasuro Sugimoto

Chemistry Faculty Publications

Aromatase is a particularly attractive drug target in the treatment of hormone-responsive breast cancer, and aromatase activity in breast cancer patients is greater in or near the tumor tissue compared with the normal breast tissue. Complex regulation of aromatase expression in human tissues involves alternative promoter sites that provide tissue-specific control. Previous studies in our laboratories suggested a strong association between aromatase (CYP19) gene expression and the expression of cyclooxygenase (COX) genes. Additionally, COX selective inhibitors can suppress CYP19 gene expression and decrease aromatase activity. Our current hypothesis is that pharmacological regulation of aromatase can act locally to decrease the …


Self-Activating Safety Mechanisms For Li-Ion Batteries, Xin-Ping Ai, Yu-Liang Cao, Han-Xi Yang Feb 2010

Self-Activating Safety Mechanisms For Li-Ion Batteries, Xin-Ping Ai, Yu-Liang Cao, Han-Xi Yang

Journal of Electrochemistry

The safety concerns of LIBs are considered to be a main obstacle to their high rate or large capacity applications in electric vehicles.This paper describes briefly our research works on the development of self-activating safety mechanisms for LIBs,including redox shuttle,potential-sensitive separator,temperature-sensitive electrode,and fire-retardent electrolyte.The problems and future in this research area are also discussed.


Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes, Wen-Hua Zhang, Yao Chen, Xin-Ping Ai, Yu-Liang Cao Feb 2010

Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes, Wen-Hua Zhang, Yao Chen, Xin-Ping Ai, Yu-Liang Cao

Journal of Electrochemistry

A sulfur/mesoporous carbon composite was prepared by thermally treating a mixture of sublimed sulfur and mesoporous carbon. The microstructure of the mesoporous carbon was characterized by BET analysis and X-ray diffraction(XRD). The electrochemical performance of the S/C composite as cathode materials was evaluated by the galvanostatic method. The results confirmed that the mesoporous carbon could not only greatly enhance the electrochemical activity of sulfur electrode, but also effectively confine the diffusion of dissolved polysulfides in organic electrolyte. As a result,the S/C composites showed high capacity, good cycle performance and excellent rate capability. The specific capacity of the S/C composite was …


The Synthesise Of Electron-Conducting Redox Hydrogel And Its Application In Microbial Fuel Cell, Kai-Peng Wang, Sheng-Li Chen Feb 2010

The Synthesise Of Electron-Conducting Redox Hydrogel And Its Application In Microbial Fuel Cell, Kai-Peng Wang, Sheng-Li Chen

Journal of Electrochemistry

Efficient electron transfer between the microbe and the anode is key for the electricity generation in Microbial fuel cell(MFC).Through the modification of anode,the rate of electron transfer can be accelerated,therefore the performance of MFC can be enhanced.In this paper,we report the synthesis of a type of electronconducting and bio-compatible redox hydrogel and its application.The hydrogel consists of poly(4-vinylpyridine) as backbone and neutral red as the redox center.By immobiliazing neutral red on the backbone through covalent bond,the secondary contamination due to the soluble redox mediator to external environment can be prevented.MFCs using the hydrogel-modified carbon anode significantly exhibit shorter acclimation period,and …


Preparation And Characterizations Of Li3V2(Po4)3 Cathode Material For Lithium Ion Batteries, Hong Chen, Tao Jiang, Chun-Zhong Wang, Gang Chen, Ying-Jin Wei Feb 2010

Preparation And Characterizations Of Li3V2(Po4)3 Cathode Material For Lithium Ion Batteries, Hong Chen, Tao Jiang, Chun-Zhong Wang, Gang Chen, Ying-Jin Wei

Journal of Electrochemistry

The carbon-coated Li3V2(PO4)3 was prepared by carbothermal reduction method.The structural and morphological properties of the material were studied by X-ray diffraction,FTIR and transmission electron microscopy.The synthesized material was a pure phase of Li3V2(PO4)3,with the particle size of about 100 nm.The values of Li ion diffusion coefficient of the material in the potential window of 3.0 ~ 4.3 V were nearly 3 orders larger than those in 3.0 ~ 4.8 V.In addition,the charge-transfer resistances in 3.0 ~ 4.3 V were much smaller than those in 3.0 …


Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials, Kai-Yuan Liu, Jian-Shu Huang, Li Yang Feb 2010

Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials, Kai-Yuan Liu, Jian-Shu Huang, Li Yang

Journal of Electrochemistry

The monoclinic Li3V2(PO4)3 cathode materials were prepared by carbothermal reduction method,with methyl cellulose, chitosan(crab shells) or glucose anhydrous as carbon sources, respectively.The crystal structures, morphologies and the electrochemical performances were characterized by XRD, SEM and electrochemical measurement. The XRD patterns show that the samples obtained at 800 ℃ for 6 h have a pure monoclinic structure,which indicates that the carbon exists in amorphous phase. Electrochemical measurements show that the difference of carbon sources has a significant influence on the electrochemical properties of the materials. The Li3V2(PO4)3 …


Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid, Bo Zhang, Si-Ting Chen, Xue-Ping Gao Feb 2010

Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid, Bo Zhang, Si-Ting Chen, Xue-Ping Gao

Journal of Electrochemistry

The sulfur-super conductive carbon black composite was prepared as cathode material of lithium/sulfur battery.The composite was characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and electrochemical impedance spectroscopy(EIS).The sulfur composite shows a high discharge capacity and a good cycle performance in electrolyte mixed with 50% of room temperature ionic liquid.In particular,the discharge capacity of the composite was stabilized at 483.6 mAh/g after 50 cycles.


Electrochemical Properties Of Ni(Oh)2 Doped By Nio, Fei-Biao Chen, Bo-Rong Wu, Wei-Feng An, Zhao-Jun Yang, Feng Wu, Shi Chen Feb 2010

Electrochemical Properties Of Ni(Oh)2 Doped By Nio, Fei-Biao Chen, Bo-Rong Wu, Wei-Feng An, Zhao-Jun Yang, Feng Wu, Shi Chen

Journal of Electrochemistry

The Ni(OH)2 cathode material of MH/Ni was doped by NiO,which behaves as a capacitor and can improve the charge-discharge rate capacity of Ni(OH)2.The electrochemical properties of Ni(OH)2 was characterized by charge-discharge curves and cyclic voltammetry.The results showed that the material had the best discharge property when doped by 5% NiO,and the discharge specific capacity could reach 310.1 mAh/g at 0.2 C rate and remianed 79.5% at 3 C rate.The difference oxidation and reduction potentials between the of the battery was 164 mV when the Ni(OH)2 was doped by 5% NiO,which showed a good cyclic property.


Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell, Xue-Min Ni, Ya-Dong Wang, Mu Pan Feb 2010

Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell, Xue-Min Ni, Ya-Dong Wang, Mu Pan

Journal of Electrochemistry

The performance of CeO2 as oxygen reduction electrocatalyst in direct borohydride fuel cell was investigated.The experimental results indicate that CeO2 shows significant electrocatalytic performance for oxygen reduction and exhibits no observed promotion effect on hydrolysis or electro-oxidation of BH4-.The power density of experimental one-compartment fuel cell with CeO2 as cathode electrocatalyst can reach a 67.8 mW·cm-2 at room temperature.


Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery, Yi-Fei Wang, Yu-Feng Tang, Zheng Qiu, Li Yang Feb 2010

Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery, Yi-Fei Wang, Yu-Feng Tang, Zheng Qiu, Li Yang

Journal of Electrochemistry

Spinel lithium titanate(Li4Ti5O12) nanosheets with a size range of 200 ~400 nm were synthesized by hydrothermal process from the amorphous hydrous titanium oxide precursors.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The electrochemical behaviors of Li4Ti5O12 electrode in conventional organic electrolyte and ionic liquid electrolyte were investigated by using cyclic voltammetry,galvanostatic charge-discharge and AC impedance techniques.The experimental results indicate that the as-prepared nanostructured Li4Ti5O12,evaluated as anode material,exhibited good reversibility and cycle performance.It is expected to be a …


Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method, Sheng-An Xia, Li-Xia Yuan, Ze Yang, Zhao-Hui Wang, Yun-Hui Huang, Shuang Li, Wu-Xing Zhang, Ya-Bin Meng, Wei-Gong Zheng Feb 2010

Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method, Sheng-An Xia, Li-Xia Yuan, Ze Yang, Zhao-Hui Wang, Yun-Hui Huang, Shuang Li, Wu-Xing Zhang, Ya-Bin Meng, Wei-Gong Zheng

Journal of Electrochemistry

Layered LiNi1/3Co1/3Mn1/3O2 is one of the most promising alternative materials for LiCoO2 in lithium ion batteries due to its low cost,large capacity and excellent cyclability.In this paper,LiNi1/3Co1/3Mn1/3O2 was synthesized via azeotropic distillation method with isobutyl alcohol as an azeotropic agent.The structure and surface morphology were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM),respectively.The as-prepared LiNi1/3Co1/3Mn1/3O2 shows a layered α-NaFeO2 structure;the particles are small and uniformly distributed.As compared with the sample prepared by traditional method,the present cathode material …


Studied Corrosion Behaviors Of Reinforcing Steel In Concrete By A Single-Dimensional Array Electrode, Lan-Qiang Li, Shi-Gang Dong, Rong-Gui Du, Chang-Jian Lin Feb 2010

Studied Corrosion Behaviors Of Reinforcing Steel In Concrete By A Single-Dimensional Array Electrode, Lan-Qiang Li, Shi-Gang Dong, Rong-Gui Du, Chang-Jian Lin

Journal of Electrochemistry

A single-dimensional array electrode was developed as a new electrochemical technique to image corrosion potential,galvanic current and polarization curves of reinforcing steel in concrete during corrosion process.Combining with the polarization behavior for each micro-electrode,the interactions between corrosion macrocell and corrosion microcell of the steel in concrete were evaluated.It was noticed that the corrosion macrocell and microcell occurred independently in difference regions at the initial stage of corrosion.The corrosion macrocell current can be in situ followed by corrosion potential imaging.The corrosion propagation of steel in concrete is closely related to the interactions between corrosion macrocell and corrosion microcell.


The Electrochemical Characteristics Of Cpo-Pll/Gc Electrode, Wen Zhao, Xia-Qin Wu, Zhong-Qing Lu, Wen-Jing Hou, He-Xing Li Feb 2010

The Electrochemical Characteristics Of Cpo-Pll/Gc Electrode, Wen Zhao, Xia-Qin Wu, Zhong-Qing Lu, Wen-Jing Hou, He-Xing Li

Journal of Electrochemistry

Poly-L-lysine(PLL) was electropolymerized onto the surface of glassy carbon(GC) electrode.1[(3-dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride(EDC) was used as a Cross-linking agent to immobilized Chloroperoxidase(CPO) onto the PLL/GC electrode.A pair of well-defined redox peaks was observed at CPO-PLL/GC electrode,which clearly suggested that PLL can promote the direct electron transfer between the CPO and the GC electrodes.The cyclic voltammetry results also showed that the electron transfer at CPO-PLL/GC is a surface adsorption-controlled quasi-reversible process,which is accompanied with proton transfer.The CPO-PLL/GC electrode exhibited a good electrochemical stability and excellently electrocatalytic activity for electrochemical reduction of O2.


Electrochemical Behavior Of Europium(Ⅲ) In 1-Butyl-3-Methylimidazolium, Qiu-Yue Zhang, Hui He, Xiao-Hong Huang, Guo-An Ye Feb 2010

Electrochemical Behavior Of Europium(Ⅲ) In 1-Butyl-3-Methylimidazolium, Qiu-Yue Zhang, Hui He, Xiao-Hong Huang, Guo-An Ye

Journal of Electrochemistry

The electrochemical behavior of EuCl3 in 1-butyl-3-methylimidazolium chlorid([BMIM]Cl) has been investigated in the temperature range of 328 ~ 348 K by cyclic voltammetry.Influences of scan speed and temperature in [BMIM]Cl have been examined.The electrochemical window of [BMIM]Cl was-1.7 V ~ 0.80 V(vs.Ag/AgCl),when the working electrode was glassy carbon electrode.Eu3+ in[BMIM]Cl underwent a single step one-electron transfer reduction to Eu2 +,which is quasi-reversible reaction controlled by both electron transfer and diffusion of ions.The diffusion coefficient of Eu3 + in [BMIM]Cl increased with increase of temperature from 3.75 × 10-9 cm2 /s at 328 K …


Electrocatalytic Reduction Of L-Cystine At Pb/Nanotio2 Film Electrode, Dao-Bao Chu, Feng Wang, Ying Xiao, Xue-Jiao Zhang Feb 2010

Electrocatalytic Reduction Of L-Cystine At Pb/Nanotio2 Film Electrode, Dao-Bao Chu, Feng Wang, Ying Xiao, Xue-Jiao Zhang

Journal of Electrochemistry

The nanoporous Ti-based TiO2 films electrodes modified with Pb particles(Pb/nanoTiO2) were prepared by using anodization and potentiostatic electro-deposition.The optimum deposition conditions were determined by comparing with various deposition potentials and time.The SEM analyses indicated that the TiO2 films were homogeneous nanoporous structure,and the Pb particles well dispersed on the TiO2 films.The L-cystine electrocatalytic activity reduction on the Pb/nanoTiO2 film electrodes was investigated by cyclic voltammetry and Chronoamperometric curves.The results showed that this type of the electrode posseses high acticity and stability.


Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode, Rui-Qi Li, Chun-Hua Song, Chao Xu, Li-Xing Tu, Guo-Hong Qiu, Fan Liu Feb 2010

Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode, Rui-Qi Li, Chun-Hua Song, Chao Xu, Li-Xing Tu, Guo-Hong Qiu, Fan Liu

Journal of Electrochemistry

Cobalt-doped todorokites were prepared by refluxing at atmospheric pressure,and then charactered by X-ray diffraction(XRD),thermogravimetry(TG) and the analysis of chemical compositions.These measurements showed that all of the refluxing products were single phase of todorokites and the structure formulas were MgxCoyMnOz·nH2O,where 0.18 ≤ x ≤ 0.22,0 ≤ y ≤ 0.24,2.10 ≤ z ≤ 2.53,and 0.35 ≤ n ≤0.73.The electrochemical characteristics of cobalt-doped todorokites were examined as lithium insertion hosts for cathodes in rechargeable lithium batteries.The first discharge capacity of undoped todorokite electrode was 211 mAh/g and the discharge capacity became 37 mAh/g after 30 …


Study Of Electrodes Modified With Hybrid Copper Cobalt Hexacyanoferrate-Mwcnts Composites, Shan Jiang, Yun Zhang, Xiao-Yan Wang, Xiao-Fei Yao Feb 2010

Study Of Electrodes Modified With Hybrid Copper Cobalt Hexacyanoferrate-Mwcnts Composites, Shan Jiang, Yun Zhang, Xiao-Yan Wang, Xiao-Fei Yao

Journal of Electrochemistry

The hybrid modified electrodes were obtained by electrochemical deposition of copper-cobalt hexacyanoferrate(CuCoHCF) /multi-walled carbon nanotubes(MWCNTs) on the surface of glassy carbon electrode.The effects of the amount of MWCNTs and composition of electrolyte on the properties of modified electrode had been researched.The copper cobalt hexacyanoferrate-MWCNTs modified electrodes show excellent electrochemical properties compared with that modified only copper-cobalt hexacyanoferrate.The CuCoHCF-MWCNTs/GCE exhibits obvious electrocatalytic activity towards oxidation of hydrogen peroxide.The oxidation peak current increased linearly with the concentration of hydrogen peroxide in the range of 3.16 × 10-5 ~ 2.92 × 10-3 mol· L-1.The linear equation is given up …


Fabrication And Characterization Of The Ni-Scsz Composite Anodes With A Lscm-Ceo2 Catalyst Layer In Thin Film Sofc, Yun-Yun Wang, Bo Huang, Xin-Jian Zhu, Wan-Qi Hu, Qing-Chun Yu Feb 2010

Fabrication And Characterization Of The Ni-Scsz Composite Anodes With A Lscm-Ceo2 Catalyst Layer In Thin Film Sofc, Yun-Yun Wang, Bo Huang, Xin-Jian Zhu, Wan-Qi Hu, Qing-Chun Yu

Journal of Electrochemistry

Solid oxide full cell(SOFC) running directly on hydrocarbon fuels has attracted much attention in recent years. In this paper, a dual-layer structure anode was fabricated by tape casting and screen printing method. The addition of a LSCM-CeO2 catalyst layer to the supported anode surface yielded better performance in ethanol fuel. The maximum power density reached 710 and 669 mW/cm2 at 850 ℃ running on hydrogen gas steam and ethanol steam,respectively. No significant degradation in performance has been observed after 216 h of cell testing when the Ni-ScSZ13 anode was exposed to the ethanol steam at 700 ℃. Very …


Application Of Sol-Gel Technology In The Of Activation Process Of Chemical Plating Pretreatment, Lin Zhang, Wei Wang, Qian-Zhen Wu Feb 2010

Application Of Sol-Gel Technology In The Of Activation Process Of Chemical Plating Pretreatment, Lin Zhang, Wei Wang, Qian-Zhen Wu

Journal of Electrochemistry

Using KH-550 as precursors,gel thin films were formed on fabric by sol-gel method.By complexed with palladium ions due to the presences of amido and hydroxide in the gel thin films,the aggregation of palladium particles was inhibited.Therefore,Palladium could exhibit better catalytic activity in the process of electroless plating.The surface morphology of fabric was observed by SPM and SEM.Campared with the traditional pretreatment process,no SnCl2 was needed.This method reduced pollution,shortened process flow and reduced the amount of noble metals.


Electrosynthesis Of P-Aminobenzenearsenic Acid, Chun-An Ma, Qin-An Zheng, Qiang Zhou, Ying-Hua Xu Feb 2010

Electrosynthesis Of P-Aminobenzenearsenic Acid, Chun-An Ma, Qin-An Zheng, Qiang Zhou, Ying-Hua Xu

Journal of Electrochemistry

The electrochemical reduction of p-nitrophenyl arsonit acid to p-aminobenzenearsenic acid was studied using controlled-current electrolysis.The results showed that the yield of p-aminobenzenearsenic acid was determinated by the following factors:the concentrations of sulphuric acid,the amount of additive,temperature and the concentrations of p-nitrophenyl arsenic acid.The optimum electrolytic conditions were obtained to be is 10% H2SO4,1% NaCl,80 ℃,25 g/350 mL p-nitrophenyl arsenic acid and 10 A·dm-2.The yield of arsanilic acid could be reached 64.7% under the optimum electrolytic conditions.


Electrochemical Capacitance Of Mno2 /Pani Composite, Xiao-Cun Xu, Kai-Yu Liu, Zhi-Gang Yin, Zhe Sun, Geng Su Feb 2010

Electrochemical Capacitance Of Mno2 /Pani Composite, Xiao-Cun Xu, Kai-Yu Liu, Zhi-Gang Yin, Zhe Sun, Geng Su

Journal of Electrochemistry

Nano-MnO2 was prepared by using P123 as a soft template.The MnO2 /polyaniline composite was further prepared by polymerization of aniline with the nano-MnO2 in acidic conditions and was investigated by XRD and IR.The morphology of nano-MnO2 observed by SEM was changed with the introduction of aniline.The electrochemical properties of MnO2 /PANI electrode were investigated using cyclic voltammetry,galvanostatic charge-discharge and electrochemical impedance spectroscopy.The specific capacitance of MnO2 /PANI electrode could reach as high as 190.8 F·g-1,which decayed only 4.7% over 500 cycles.And the coulombic efficiency has been maintained at above 97%.


Electrochemical Corrosion Behavior Of Tio2/Ha Composite Coating On Medical Titanium In Tyrode's Physiological Solution, Li-Li Kong, Long-Xiang Lin, Rong-Gang Hu, Fan Zhang, Chang-Jian Lin Feb 2010

Electrochemical Corrosion Behavior Of Tio2/Ha Composite Coating On Medical Titanium In Tyrode's Physiological Solution, Li-Li Kong, Long-Xiang Lin, Rong-Gang Hu, Fan Zhang, Chang-Jian Lin

Journal of Electrochemistry

Titanium and its alloys have been widely used as medical implant materials because of their good mechanical properties and biocompatibility.However,the physiological corrosion of metal will release metal ions,resulting in toxic and side effects.In this paper,in order to improve the corrosion resistance of titanium,and to enhance its bioactivity and osseointegration,the surface modification of titamum were performed.Using eletrochemical methods Tafel polarization and electrochemical impedance spectroscopy(EIS) were applied to study the electrochemical corrosion behavior of TiO2 /HA composite coating.It is indicated that the corrosion resistance of the prepared TiO2 /Ti material in Tyrode's physiological solution is improved because of the enhanced …


Electrochemical Behavior Of Co-Ru Composite In Alkaline Solution, Su-Mei Yao, Guo-Chun Li, Xue-Ping Gao Feb 2010

Electrochemical Behavior Of Co-Ru Composite In Alkaline Solution, Su-Mei Yao, Guo-Chun Li, Xue-Ping Gao

Journal of Electrochemistry

The electrochemical properties of Ru doped cobalt hydroxides synthesized via homogeneous chemical co-precipitation were investigated in 6 mol·L-1 KOH solution by galvanostatic charge-discharge process and cyclic voltammetry(CV).It is demonstrated that Ru doped cobalt hydroxides exhibited good capacitive characteristic and high specific capacitance.The sample with a Co/Ru molar ratio of 8 /1 shows the optimized electrochemical performance,including capacitive property and discharge capacity.The microstructure and morphology of the obtained Ru doped hydroxides were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM).The amorphous structure of ruthenium dioxide nanoparticles and single-crystal structure of Co(OH)2 platelets were confirmed.Based on a structure analysis and …


Applications Of Block Copolymer Films In The Field Of Electrochemical Energy Systems, Jing-Ze Li, Guo-Guang Chen, Di Mei, Wei Zou, Jian-Wen Li, Motonori Komura, Tomokazu Iyoda Feb 2010

Applications Of Block Copolymer Films In The Field Of Electrochemical Energy Systems, Jing-Ze Li, Guo-Guang Chen, Di Mei, Wei Zou, Jian-Wen Li, Motonori Komura, Tomokazu Iyoda

Journal of Electrochemistry

A new series of amphiphilic liquid crystalline block copolymer thin films,having normally aligned and highly ordered nanocylinder array,were functionalized as anisotropic ion conducting materials by selectively infiltration.These ion-active nanocylinders are coaxially aligned and hexagonally arranged in a large area,which might be used as novel types of electrolyte films for electrochemical energy systems such as lithium ion battery,fuel cell,etc.Since the ordered cylinders can carry on and store the ions,the block copolymer films can be utilized as the advanced template to fabricate the ordered array of nanoporous,nanoparticles,and nanowires for the potential application in lithium ion battery as three dimensional electrode materials.


Nmr Dynamics Investigation Of Ligand-Induced Changes Of Main And Side-Chain Arginine N-H’S In Human Phosphomevalonate Kinase, Andrew L. Olson, Sheng Cai, Timothy J. Herdendorf, Henry M. Miziorko, Daniel S. Sem Feb 2010

Nmr Dynamics Investigation Of Ligand-Induced Changes Of Main And Side-Chain Arginine N-H’S In Human Phosphomevalonate Kinase, Andrew L. Olson, Sheng Cai, Timothy J. Herdendorf, Henry M. Miziorko, Daniel S. Sem

Chemistry Faculty Research and Publications

Phosphomevalonate kinase (PMK) catalyzes phosphoryl transfer from adenosine triphosphate (ATP) to mevalonate 5-phosphate (M5P) on the pathway for synthesizing cholesterol and other isoprenoids. To permit this reaction, its substrates must be brought proximal, which would result in a significant and repulsive buildup of negative charge. To facilitate this difficult task, PMK contains 17 arginines and eight lysines. However, the way in which this charge neutralization and binding is achieved, from a structural and dynamics perspective, is not known. More broadly, the role of arginine side-chain dynamics in binding of charged substrates has not been experimentally defined for any protein to …


Remarkable Iodine-Catalyzed Synthesis Of Novel Pyrrole- Bearing N-Polyaromatic B-Lactams, Debasish Bandyopadhyay, Gildardo Rivera, Isabel Salinas, Hector Aguilar, Bimal K. Banik Feb 2010

Remarkable Iodine-Catalyzed Synthesis Of Novel Pyrrole- Bearing N-Polyaromatic B-Lactams, Debasish Bandyopadhyay, Gildardo Rivera, Isabel Salinas, Hector Aguilar, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Because of their interesting biological properties various methods for the synthesis of substituted pyrroles are described in the literature. However, synthesis of pyrroles fused with a β-lactam ring has not been reported. Our group has demonstrated synthesis and biological evaluation of various β-lactams as anticancer agents. The anticancer activities of these compounds have prompted us to study the synthesis of pyrroles bound to the β-lactams. We have identified an expeditious synthetic method for the preparation of pyrroles fused with β-lactams by reacting 3-amino β-lactams with acetonylacetone in the presence of catalytic amounts (5 mol%) of molecular iodine at room temperature. …


Water-Soluble Soa From Alkene Ozonolysis: Composition And Droplet Activation Kinetics Inferences From Analysis Of Ccn Activity, A. Asa-Awuku, A. Nenes, Song Gao, R. C. Flagan, John H. Seinfeld Feb 2010

Water-Soluble Soa From Alkene Ozonolysis: Composition And Droplet Activation Kinetics Inferences From Analysis Of Ccn Activity, A. Asa-Awuku, A. Nenes, Song Gao, R. C. Flagan, John H. Seinfeld

Chemistry and Physics Faculty Articles

Cloud formation characteristics of the water-soluble organic fraction (WSOC) of secondary organic aerosol (SOA) formed from the ozonolysis of alkene hydrocarbons (terpinolene, 1-methlycycloheptene and cycloheptene) are studied. Based on size-resolved measurements of CCN activity (of the pure and salted WSOC samples) we estimate the average molar volume and surface tension depression associated with the WSOC using Köhler Theory Analysis (KTA). Consistent with known speciation, the results suggest that the WSOC are composed of low molecular weight species, with an effective molar mass below 200 g mol−1. The water-soluble carbon is also surface-active, depressing surface tension 10–15% from that of pure …


Thermal Degradation Of High-Temperature Fluorinated Polyimide And Its Carbon Fiber Composite, Andrea D. Adamczak, Adam A. Spriggs, Danielle M. Fitch, Walid Awad, Charles A. Wilkie, Jaime C. Grunlan Feb 2010

Thermal Degradation Of High-Temperature Fluorinated Polyimide And Its Carbon Fiber Composite, Andrea D. Adamczak, Adam A. Spriggs, Danielle M. Fitch, Walid Awad, Charles A. Wilkie, Jaime C. Grunlan

Chemistry Faculty Research and Publications

No abstract provided.