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Chinese Chemical Society | Xiamen University

Articles 1591 - 1620 of 2294

Full-Text Articles in Physical Sciences and Mathematics

Synergisms Of Electric Or Electromagnetic Fields And Photodynamic Effects Induce Apoptosis And Necrosis Of Cancer Cells, Radeva Maria, Lambrera Maya, Angelova Plamena, Traitcheva Nelly, Berg Hermann Aug 2004

Synergisms Of Electric Or Electromagnetic Fields And Photodynamic Effects Induce Apoptosis And Necrosis Of Cancer Cells, Radeva Maria, Lambrera Maya, Angelova Plamena, Traitcheva Nelly, Berg Hermann

Journal of Electrochemistry

Weak pulsating sinusoidal electromagnetic fields (PEMF) have been applied to change membrane permeation and induction of apoptosis (necrosis). In the case of suspension of human cancer cells U-937 and K-562 inside of Helmholtz-coils the amplitude of PEMF B=10 and at 39mT (at 50 Hz) was combined gradually with the cytotoxic agent actinomycin-C on one hand with its novel photodynamic activity on the other. Depending on temperature, pH-value and treatment time the necrosis of these cells was determined by means of trypan blue staining as well as the induced apoptosis by FACScan technique. Synergisms were discovered yielding high rates of cell …

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Chemical Microetching Of Three-Dimensional Gear-Like Pattern On Nickel Surface, Zhu-Fang Liu Aug 2004

Chemical Microetching Of Three-Dimensional Gear-Like Pattern On Nickel Surface, Zhu-Fang Liu

Journal of Electrochemistry

The chemical micromachining on nickel surface with three-dimensional (3D) gear-like mold was realized by confined etchant layer technique (CELT). By using effective chemical etching and scavenging system (HNO_(3) + NaOH) and optimizing experimental parameters, such as the etching time, etching current density, concentration of the etchant or and scavenger, we obtained the etched pattern, which is close to negative copy of the mold. The etched micro-pattern characterized by SEM and AFM, demonstrates that CELT can be applied to the 3-D microstructure replication on nickel surface .

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The Electrochemical Behavior And Determination Of Gsh At The Powder Microelectrode, Jian Chen, Zhong-Yu He, Chuansin Cha, Huan Liu Aug 2004

The Electrochemical Behavior And Determination Of Gsh At The Powder Microelectrode, Jian Chen, Zhong-Yu He, Chuansin Cha, Huan Liu

Journal of Electrochemistry

In this paper, the electrochemical behavior of GSH at the surface of platinum(Pt) electrode, glass carbon(GC) electrode and acetylene black packed powder microelectrode (AB-PME) was studied. It was found that the electrochemical oxidations of GSH at both Pt and GC electrode were highly irreversible. No current peak or current plateau could be observed from the CV curves. The direct electro-oxidation of GSH at carbon surface was achieved by using the PME technique.In this case, the apparent reversibility of GSH oxidation was enhanced significatly .The overpotential of GSH oxidation was reduced to 0.5 V at the surface of AB-PME compared with …

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Nucleation And Crystal Growth Of Pt Electrodeposition On Poly Crystal Au Microdisc Electrode, Zhi-Yong Tao, Pei-Fang Liu Aug 2004

Nucleation And Crystal Growth Of Pt Electrodeposition On Poly Crystal Au Microdisc Electrode, Zhi-Yong Tao, Pei-Fang Liu

Journal of Electrochemistry

Based on the Fleischmann's model of nucleation and crystal growth for electrodeposition combined with the Barradas-Bosco's adsorption-nucleation model for electrochemical phase formation, the chronoamperometry was well fitted for Pt deposition on polycrystalline Au micro disc electrodes (30 μm in diameter) in different H_(2)PtCl_(6) concentrations at different over-potentials. The initial stage of Pt deposition in dilute H_(2)PtCl_(6) could be interpreted by the model of H_(2)PtCl_(6 ) adsorption combined with instantaneous nucleation and two-dimensional cylindrical growth. The rate constant of the two-dimensional growth increased linearly with overpotential. Then the deposit grew layer by layer and the rate constant increased non-linearly with overpotential. …

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Preparation And Electrochemical Performance Of New Composite Seperators For Lithium-Ion Batteries, Hu Cheng, Hong-Yan Du, Yong Yang Aug 2004

Preparation And Electrochemical Performance Of New Composite Seperators For Lithium-Ion Batteries, Hu Cheng, Hong-Yan Du, Yong Yang

Journal of Electrochemistry

New composite seperators for lithium ion batteries were prepared by coating PEO mixed with nanosize SiO_(2)onto microporous polypropylene(PP) seperators. Highly conductive electrolytes were prepared by soaking them in an electrolyte solution. With these composite separators, the lithium ion cell consisting of Li anode and LiNi_(0.8)Co_(0.2)O_(2)cathode were assembled. The high initial discharge capacity and good capacity retention were obtained through the cell.

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Synthesis Of (S)-3-Phenylpropane-2-Tert-Butoxycarbonylamino- 1-Thiol And Its Electrochemical Behavior Self-Assembled On Gold, Sun Ru Aug 2004

Synthesis Of (S)-3-Phenylpropane-2-Tert-Butoxycarbonylamino- 1-Thiol And Its Electrochemical Behavior Self-Assembled On Gold, Sun Ru

Journal of Electrochemistry

The synthesis of (S)-3-Phenylpropane-2-tert-butoxycarbonylamino- 1-thiol(N-Boc-APT) from L-phenylalanine was reported. L-Phenylalanine was reduced to the corresponding amino alcohol, protection of the amino group using tert-butyl pyrocarbonate gave (S)-2-tert-butoxycarbonylamino-3-phenylpropane-1-ol, which was then O-mesylated and treated with potassium thioacetate in DMF to give 3-phenylpropane-2-tert- butoxycarbonylamino-1-etylmercapto. After the acetyl group was removed with ammonia in alcohol, the desired target molecular was obtained. The structure of intermediate and target molecular was conformed by IR and ~(1)HNMR. We made N-Boc-APT self-assemble-modificated gold electrode and investigated its electrochemical behavior. The CV results of methylene blue on nano-Au/N-Boc-APT SAM/Au electrode showed that nano-Au could speed this electron transfer …

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Lithium Insertion Into Tio_2(B) Nanobelts Synthesized By The "Soft Chemical" Method, Cha-Geng Nie, Zheng-Liang Gong, Lan Sun, Juan Zuo, Yue-Kun Lai, Chang-Jian Lin Aug 2004

Lithium Insertion Into Tio_2(B) Nanobelts Synthesized By The "Soft Chemical" Method, Cha-Geng Nie, Zheng-Liang Gong, Lan Sun, Juan Zuo, Yue-Kun Lai, Chang-Jian Lin

Journal of Electrochemistry

TiO_(2)(B) Nanobelts were synthesized by using the "Soft chemical"method. The products were characterized by means of transmission electron microscope(TEM), X-ray diffraction(XRD), Raman spectrum and energy dispersive spectrum(EDS). Galvanostatic charging and discharging tests showed that lithium-ion intercalation/deintercalation occurred reversibly in the TiO_(2)(B) nanobelts electrode, and a high capacity (265 mAh·g~(-1)) can be obtained. The results suggested that TiO_(2)(B) Nanobelts might be a promising negative electrode material of second Lithium battery.

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Preliminary Study Of Speek Membranes For Direct Methanol Fuel Cells Application, Su-Zhen Ren Aug 2004

Preliminary Study Of Speek Membranes For Direct Methanol Fuel Cells Application, Su-Zhen Ren

Journal of Electrochemistry

This paper describes the methanol permeability characterization of SPEEK membranes and their feasibility for DMFC application. The SPEEK membranes showed a significant lower methanol permeation than Nafion~115 determined from voltammetric methods. An increase in open circuit voltage was found in the performance of SPEEK membranes in DMFC. The power density of the cell using SPEEK membrane was considerably poorer than that of Nafion~115. If modified properly, the SPEEK membranes can be chosen for DMFC application based on this study.

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Fabrication Of Solid Oxide Fuel Cells And Analysis Of Their Structure And Performance, Nai-Tao Yang Aug 2004

Fabrication Of Solid Oxide Fuel Cells And Analysis Of Their Structure And Performance, Nai-Tao Yang

Journal of Electrochemistry

An intermediate temperature solid oxide fuel cell (IT-SOFC) was fabricated by co-copressing-sintering methods, and the electrolyte of Ce_(0.8)Gd_(0.2)O_(1.9) (CGO) and cathode materials of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-α) (LSCF) were prepared by sol-gel method. The effect of preparation methods on the microstructure of the prepared fuel cells was analyzed by SEM . It shows that the cells prepared by the co-pressing/co-sintering method possess a dense electrolyte layer and a compact interface between electrolyte and anode but a curved configuration, while those prepared by the colloidal technique have a flat configuration but the electrolyte layer is not dense enough. The maximum output power density of …

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The Effect Of Ferrous Sulphate On The Electroless Depositionof Co-Fe-P Alloys, Sen-Lin Wang, Qing-Hua Li Aug 2004

The Effect Of Ferrous Sulphate On The Electroless Depositionof Co-Fe-P Alloys, Sen-Lin Wang, Qing-Hua Li

Journal of Electrochemistry

Electroless deposition of Co-P alloy and Co-Fe-P alloy from an alkaline bath, containing sodium hypophosphite as a reducer, boric acid as a buffer agent and sodium citrate as a complexing agent, was investigated respectively. The effects of process parameters, such as pH of solution and metallic salt mole ratio of CoSO_(4)/FeSO_(4), on the plating rate were examined. It was found that the presence of ferrous sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the plating rate of Co-Fe-P is lower than that of Co-P. The electrochemical polarization measurements have been carried out to …

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Study On The Electrochemical Behaviors Of Prussian Blue Film Using Electrochemical Quartz Crystal Microbalance, Hui Liao, Xia-Qin Wu, Zong-Rang Zhang Aug 2004

Study On The Electrochemical Behaviors Of Prussian Blue Film Using Electrochemical Quartz Crystal Microbalance, Hui Liao, Xia-Qin Wu, Zong-Rang Zhang

Journal of Electrochemistry

Prussian blue (PB) films were electrodeposited on the Pt/QCMelectrodes in the solutions with or without Phenanthroline by cyclic voltammetry. The frequencyshift during electrodeposition wasmeasured,and the EQCM behaviors of these two types of PB films in potassium chloridewere also studied. Results show that electrodeposition process of PB film in the solution with phenanthroline wasdifferent from that in the solution without phenanthroline. The PB film modified Pt/QCMelectrodeprepared in the solution with phenanthroline shown an excellent electrocatalytic activity for the reduction process of hydrogen peroxide.

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Preparation Of Photo-Electrochemical Anticorrosion Tio_2 Films By Anodization Method, Peng-Fei Wu, Mou-Cheng Li, Jia-Nian Shen, Mei-Qun Xiao, Dong Liu Aug 2004

Preparation Of Photo-Electrochemical Anticorrosion Tio_2 Films By Anodization Method, Peng-Fei Wu, Mou-Cheng Li, Jia-Nian Shen, Mei-Qun Xiao, Dong Liu

Journal of Electrochemistry

Titanium oxide films have photo-electrochemical anticorrosion effect. We investigated the TiO_(2) films prepared by anodization method to protect for 45~(#) carbon steel in man-made seawater(3%NaCl). Various parameters, including voltages, electrolytes nature and concentration of electrolyte were examined. The polarization curves and of TiO_(2) and coupling photo-current curve between TiO_(2) film and 45~(#) carbon steel were measured.

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Electrochemical Reduction Of Nitrobenzene On The Wc Electrode In Acidic Solution, Chun-An Ma Aug 2004

Electrochemical Reduction Of Nitrobenzene On The Wc Electrode In Acidic Solution, Chun-An Ma

Journal of Electrochemistry

The tungsten carbide (WC) electrode was constructed by using polyterafluoroethylene as binder. The electrochemical behavior of nitrobenzene on the WC electrode in acidic solution was investigated by cyclic voltammetry, linear scan method and chronoamperometry. Experimental results showed that WC electrode had good activity for the electrochemical reduction of nitrobenzene, and the electrode process was controlled by diffusion and electrochemical stepssimultaneously. The apparent active energy of the electrode process is 23.7kJ mol~(-1), while the active energy of the electrochemicalstep is 10.91kJ mol~(-1).

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Solid State Synthesis And Electrocatalysis Of Pt/Moo_3 For The Oxidation Of Methanol, Wang Qing Aug 2004

Solid State Synthesis And Electrocatalysis Of Pt/Moo_3 For The Oxidation Of Methanol, Wang Qing

Journal of Electrochemistry

The electrocatalyst, Pt/MoO_(3) synthesized by solid state reaction, was used for the oxidation of methanol in direct methanol fuel cells. The X-Ray diffraction and cyclic voltammetry were employed to investigate the performance of the material. It was shown that the typical diffraction peaks for Pt appeared in XRD. And a good electrocatalysis for methanol oxidation was observed. The peak potential of the methanol oxidation appeared at ca. 0.63V(vs.SCE) and the peak current density for the oxidation was 78.1 mA cm~(-2) .

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Adual-Celltechnique And Its Application In Electrocatalytic Study Of Pt-Ru Metals, Lei Su, Bing-Liang Wu Aug 2004

Adual-Celltechnique And Its Application In Electrocatalytic Study Of Pt-Ru Metals, Lei Su, Bing-Liang Wu

Journal of Electrochemistry

Two local electrochemical reactive interfaces are established using two strips of Nafion~ membrane separated each other, which are in contact with different surface regions of the same metal-sheet working electrode. One potentiostatis used to control thepotentialof one electrochemical reactive interface to generate adsorbed surface speciesand the other potentiostatto hold the potential of the second interface as a detector of the intermediate. The adsorbed surface species driven by the difference in surface concentration diffuses alongthe surface of the metal-sheet between both local electrochemical interfaces and can be detected at the second interface when they achieveover there.The surface diffusion coefficient of the …

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Effects Of Barium On The Performance Of Secondary Alkaline Zinc Electrode, Yi Zheng, Jian-Ming Wang Aug 2004

Effects Of Barium On The Performance Of Secondary Alkaline Zinc Electrode, Yi Zheng, Jian-Ming Wang

Journal of Electrochemistry

The active material of secondary alkaline zinc electrode with barium additives was prepared by a chemical reaction method and characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The electrochemical performance of various pasted Zn electrodes was investigated by cyclic voltammetry, charge/discharge method and electrochemical impedance spectra (EIS) technology. The addition of barium can synthesize a compound barium zincate with the molecular structure of BaZn(OH)_(4)· xH_(2)O and improve the discharge performance. The EIS of the various Zn electrodes showed two time constants besides diffusion impedance, including a state variable representing the covering degree of discharge products on the electrode …

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Studies On The Electrochemical Behavior Of Copper Paratolysulfate And Its Complexes, Ji-Guo Song, Pei-Kang Shen Aug 2004

Studies On The Electrochemical Behavior Of Copper Paratolysulfate And Its Complexes, Ji-Guo Song, Pei-Kang Shen

Journal of Electrochemistry

Copper (II) paratolysulfate has been synthesized and characterized by thermo-gravimetric (TG) measurements and differential scanning calorimetric (DSC) analysis. This salt can easily lose all crystal water and the dehydrated salt does not deliquesce in the air. It is found for the first time that the complex of Cu(p-OTs)_(2)/ethanolamine(1∶1) can catalyze the oxidation of 1,1′-bi-2-naphthol in DMSO and DMF, while the process is difficult to perform in H_(2)O and CH_(3)OH. The electrochemical behaviors of both Cu(p-OTs)_(2) and its complexes with ethanolamine have been studied on platinum electrode in DMSO, DMF, (CH_(3)OH) and H_(2)O respectively. The complexes of various copper salts with …

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Synthesis And Electrochemical Behavior Of Layered-Structure Limn_(1-X)Cr_Xo_2, Jie Xiao, Hui Zhan, Yun-Hong Zhou Aug 2004

Synthesis And Electrochemical Behavior Of Layered-Structure Limn_(1-X)Cr_Xo_2, Jie Xiao, Hui Zhan, Yun-Hong Zhou

Journal of Electrochemistry

The Layered-structure LiMn_(1-x)Cr_xO_(2 )(x=0,0.15) solid solution has been prepared by the rheological phase method. From the XRD results, undoped LiMnO_(2) crystallized almost entirely in the orthorhombic phase while the structure of LiMn_(0.85)Cr_(0.15)O_(2) belongs to monoclinic phase. TEM investigation shows that the final powder product consists of ultrafine spherical particles which are distributed homogeneously, with the average diameter ranging from 60 to 300nm. The initial discharge capacity of LiMn_(0.85)Cr_(0.15)O_(2) is much higher than that of undoped LiMnO_(2). After 40 cycles, the capacity retention for m-LiMn_(0.85)Cr_(0.15)O_(2 )is 94% at the current rate of 50mA/g under room temperature. The results of electrochemistry tests …

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Study On An Intermediate Temperature Planar Solid Oxide Fuel Cell, Shao-Rong Wang, Wen-Xia Chen, Ting-Lian Wen, Jia-Di Cao, Zhi-Yi Lv, Da-Qian Wang Aug 2004

Study On An Intermediate Temperature Planar Solid Oxide Fuel Cell, Shao-Rong Wang, Wen-Xia Chen, Ting-Lian Wen, Jia-Di Cao, Zhi-Yi Lv, Da-Qian Wang

Journal of Electrochemistry

Tape cast method was applied to prepare green sheets of Ni/YSZ anode supported YSZ thin film. After isostatic pressure treatment and cosintering, the YSZ film on the Ni/YSZ anode was gas-tight dense, and 15~30 μm thick. The area of the composite film was over 100 cm~(2). A Ce_(0.8)Sm_(0.2)O_(1.9 )(CSO) interlayer was sintered on to the YSZ electrolyte film to protect La_(0.6)Sr_(0.4)CoO_(3 )(LSCO) cathode from reaction with YSZ at high temperatures. The LSCO cathode layer was screen printed onto the CSO interlayer and sintered at 1 200 ℃ for 3h to form a single cell. The obtained single cell was operated …

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Exceptional Electrochemical Activities Of Amorphous Fe-B And Co-B Alloy Particles Used As High Capacity Anode Materials, Ya-Dong Wang, Xin-Ping Ai, Han-Xi Yang May 2004

Exceptional Electrochemical Activities Of Amorphous Fe-B And Co-B Alloy Particles Used As High Capacity Anode Materials, Ya-Dong Wang, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

Ultrafine amorphous alloy particles (UAAP) of Fe-B and Co-B were synthesized and tested for possible use as electroactive anode materials. It is found that unlike their parent elements, the alloy particles of transition metal (TM) and boron, the Fe-B and Co-B showed superior electrochemical activities when used as anodic materials in aqueous alkaline solution. The discharge capacities of Fe-B and Co-B electrodeswere observed to be 1 200 mAh/gand 1 100 mAh/gat moderately high rate of 100 mAh/g, respectively, much higher than the theoreticalcapacity of currently used zinc metal (820 mAh/g). The exceptional high capacities of the boride alloys were probably …

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Investigation Of Adsorption And Oxidation Behavior Of Isosafrole On A Smooth Pt, Xiao-Hong Zhang May 2004

Investigation Of Adsorption And Oxidation Behavior Of Isosafrole On A Smooth Pt, Xiao-Hong Zhang

Journal of Electrochemistry

The electro-oxidation of isosafrole on a smooth platinum electrode was investigated in the non-aqueous solution. The CV curve shows two oxidation peaks and one reduction peak in the potential region between -0.5 V and 1.95 V. The relation between the oxidation and reduction peaks has been determined also by CV. The adsorption behavior of isosafrole on Pt was also investigated.

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Study On Electrochemical Properties Of Peo-Based Composite Polymer Electrolytes, Hong-Yan Du, Hu Cheng, Yong Yang May 2004

Study On Electrochemical Properties Of Peo-Based Composite Polymer Electrolytes, Hong-Yan Du, Hu Cheng, Yong Yang

Journal of Electrochemistry

Composite polymer electrolytes were prepared by introducing nano-scale SiO_(2)into PEO_(8)-LiClO_(4)matrix. The ionic conductivity, lithium transference number and the electrochemical stability windows were measured. The phase component was evaluated with DSC techniques. The results showed that the introduction of nano fillers enhanced the ionic conductivity. It reached 4.3×10~(-5 ) S·cm~(-1)at 22 ℃. The conductivity enhancement of the composite polymer electrolytes is analyzed and proposed.

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Preparation And Optical Properties Of Highly Ordered Cds Nanowire Arrays, Lan Sun, Chang-Jian Lin May 2004

Preparation And Optical Properties Of Highly Ordered Cds Nanowire Arrays, Lan Sun, Chang-Jian Lin

Journal of Electrochemistry

Highly ordered CdS nanowire arrays have been prepared by using dc electrodeposition in the porous anodic aluminum oxide template. Scanning electro microscopy (SEM) and transmission electron microscopy (TEM) reveal that the nanowires are uniform and highly ordered. The measurements of X-ray diffraction and high-resolved electron microscopy (HRTEM) show that the nanowires are hexagonal structure with the crystallographic c-axis preferentially oriented along the length of the pore. The UV-Vis absorption spectra of CdS nanowire arrays show that the absorption edges of the nanowire arrays shift towards short wavelength with the decrease of the nanowire size. The photoluminescence measurements show that the …

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Stability And Electrochemical Performance Of Nio Cathode Modified By Zno Additive For Mcfc In Molten Carbonates, Huang Bo May 2004

Stability And Electrochemical Performance Of Nio Cathode Modified By Zno Additive For Mcfc In Molten Carbonates, Huang Bo

Journal of Electrochemistry

The ZnO/Ni composite cathode was fabricated by tape-casting method, which microstructures and phases were studied. The electrochemical behaviors of ZnO impregnated NiO cathodes were also evaluated in molten 62 mol%Li_2CO_3+(38 mol%) K_2CO_3eutectic at 650 ℃ by electrochemical impedance spectroscopy (EIS) as a function of ZnO content and immersion time. The ZnO impregnated nickel cathodes showed the similar porosity, pore size and morphology to the reference nickel cathode. The stability tests of ZnO impregnated NiO cathodes showed that the ZnO additive could dramatically reduce the solubility of NiO in a eutectic carbonate mixture under the standard cathode gas condition. The cathode …

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Preparation, Characterization And Photoelectrochemical Activities Of Cu-Tio_2/Ito Films, Dong Shu May 2004

Preparation, Characterization And Photoelectrochemical Activities Of Cu-Tio_2/Ito Films, Dong Shu

Journal of Electrochemistry

Cu-TiO_(2)/ITO films were prepared by direct photo-reduction deposition of Cu~(2+) on TiO_(2)/ITO films. The nanocomposite films were characterized by UV-vis diffuse reflectance spectra (DRS), XRD spectra, Scanning Electron Microscope (SEM) technology, and photovoltage measurement. The feasibility of improving the photocatalytic activity of TiO_(2) film by combining the modification of Cu nanoparticles with the application of anodic bias was investigated. The experimental results showed that the deposited Cu has an apparent enhancement effect with respect to suppressing the recombination between the photogenerated charge carriers and enhancing the photocatalytic oxidation of formic acid. The combination could promote the photocatalytic oxidation of formic …

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Electrodeposition Of Copper Into Trenches Under Rotating Hydrodynamic Condition, Jian-Jun Sun May 2004

Electrodeposition Of Copper Into Trenches Under Rotating Hydrodynamic Condition, Jian-Jun Sun

Journal of Electrochemistry

Silicon chips patterned with treneches were fixed onto a rotating electrode. Copper was electrodeposited into the trenches under rotating hydrodynamic conditions The sizes of the trenches are 1 m in height and 0.35 m, 0.50 m and 0.70 m in width, respectively. The effects of rotating of the chip, the current density and the concentration of Cu~(2+ )on the filling of thetrenches were studied. It is found that lower current density and moderate concentration of Cu~(2+)resulted in a void free filling of the trenches.

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Study Of Anti-Corrosion Property On Poly(An-Co-Oas)/Epoxy, Qing-Wu Wang, Geng-Chao Wang May 2004

Study Of Anti-Corrosion Property On Poly(An-Co-Oas)/Epoxy, Qing-Wu Wang, Geng-Chao Wang

Journal of Electrochemistry

polyaniline, polyanisidine and their copolymer poly(An-co-oAs) were synthesized via the solution chemical oxidative polymerization of aniline and anisidine in an acidic aqueous medium, and their properties and structure were characterized. The electrochemical method were applied to evaluate the corrosion behavior of tined iron uncoated or coated by polyaniline, poly(An-o-oAs), polyanisidine and poly(An-co-oAs)/epoxy blend in acid or saline aqueous solution. The result showed that with the increase of anisidine content, the solubility of polymers is improved apparently but their oxidation extent decreases accordingly. It is also founded that polyaniline, poly(An-co-oAs) and polyanisidine all have good anti-corrosion properties, and their anti-corrosion capacity …

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Electrocatalytic And Lifetime Studies Of Commercial Catalystsin A Pemfc, Cheng Xuan May 2004

Electrocatalytic And Lifetime Studies Of Commercial Catalystsin A Pemfc, Cheng Xuan

Journal of Electrochemistry

A particularly designed H-type cell was used to simulate the operating condition of a hydrogen-air proton exchange membrane fuel cell (PEMFC). The electrocatalytic activity, morphology, structure and lifetime of commercially available catalysts, carbon support platinum (Pt/C) and unsupported platinum-ruthenium (Pt-Ru), were preliminary studied by carrying out electrochemical measurements and by SEM, XRD techniques. The catalysts were simultaneously tested in the H-cell under operation, and also separately tested in a conventional electrochemical cell for comparison. It was found that the characteristic peaks of hydrogen adsorption/desorption on cyclic voltammograms shifted considerably to a more positive direction for Pt/C, while a more negative …

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Structures And Redox Activities Of Poly(M-Methoxyaniline), Yun-You He May 2004

Structures And Redox Activities Of Poly(M-Methoxyaniline), Yun-You He

Journal of Electrochemistry

Poly(m-methoxyaniline), PmMAn, was prepared in the presence of HCl, p-toluene-sulfonic acid and perchloric acid. By using cyclic voltammetry, the effect of different acid dopant on electrochemical activities of PmMAn was studied. The results showed that perchloric acid is the best acid to prepare PmMAn with good electrochemical activities The FTIR spectra indicate that the acid radical anions have embedded into PmMAn molecularchain as counter-ion during synthetic process, and this great influences the redox activities of PmMAn. SEM and XRD measurements illustrate that PmMAn is characterized by its typical molecular crystalline being monoclinic.

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Electrochemical Lithium Insertion Of Nanosized Tio_2, Ying Lan, Jian-Wen Liu, Xue-Ping Gao, Xing-Di Zhou, Jin-Qiu Qu, Feng Wu, De-Ying Song May 2004

Electrochemical Lithium Insertion Of Nanosized Tio_2, Ying Lan, Jian-Wen Liu, Xue-Ping Gao, Xing-Di Zhou, Jin-Qiu Qu, Feng Wu, De-Ying Song

Journal of Electrochemistry

The protonic titanate nanotubes with the diameter of 10～15 nm were synthesized via hydrothermal method in NaOH solution and the calcined nanotubes at 500 ℃ were transferred to anatase nanorods with the diameter of 12～20 nm due to dehydration.The electrochemical behavior of the anatase nanorods as lithium insertion materials was examined. The results showed that the nanorod electrode had the high initial discharge capacity of 232 mAh/g and second reversible capacity of 198 mAh/g. The capacity of nanorod electrode maintained 152mAh/g after 20 cycles.

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