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Full-Text Articles in Physical Sciences and Mathematics

Electrochemical Controllable Preparation Of Hydroxyapatite Coating With Different Morphologies And Preliminary In Vitro Tests, Hai-Yan Shi, Ren Hu, Chang-Jian Lin Nov 2005

Electrochemical Controllable Preparation Of Hydroxyapatite Coating With Different Morphologies And Preliminary In Vitro Tests, Hai-Yan Shi, Ren Hu, Chang-Jian Lin

Journal of Electrochemistry

The Controllable electrochemical deposition has been developed to prepare the hydroxyapatite(HA) coatings on Ti substrate with different morphologies and structures.Three kinds of typical topography of HA coatings,i.e.standing-up,flower and ordered porous structures have been obtained.The XRD and FTIR results demonstrate high crystallinity of the coating and exclusion of other forms of calcium phosphates.In vitro tests reveal that the biological property is largely dependent on the structure and morphology of the HA coating.It has been found that all pure HA coating show good biocompatibilities,while only the HA coating with ordered porous structures exhibits best bioactivities.


Electrochemical Properties Of Aloe Emodin In Aqueous And Nonaqueous Solvents, Li-Ying Huang, Zhong-Cheng Wang, Li-Min Lai, Xin-Hua Lin, Wei Chen Nov 2005

Electrochemical Properties Of Aloe Emodin In Aqueous And Nonaqueous Solvents, Li-Ying Huang, Zhong-Cheng Wang, Li-Min Lai, Xin-Hua Lin, Wei Chen

Journal of Electrochemistry

Electrochemical properties of Aloe emodin in aqueous and nonaqueous solvents of DMSO were studied by cyclic voltammetry and linear sweep voltammetry at a platinum electode.A pairs of currents on the voltammogram may be attributed to a quasi-reversible-one-electron transfer in HAc-NaAc and DMSO,the peak potential in DMSO was found to move more negatively compared with that in HAc-NaAc.A new method for Aloe emodin determination is described.The peak current is proportional to the concentration of Aloe emodin over the ranges of 1.0×10~(-5)~6.0×10~(-4)mol/L.(The electrochemical properties of Aloe emodin were related to solvents.)


The Electrocatalystic Investigation Of 3,4-Dihydroxybenzoic Acid On The Modified Multiply Wall Carbon Nanotubes, Ming-Qi Li Nov 2005

The Electrocatalystic Investigation Of 3,4-Dihydroxybenzoic Acid On The Modified Multiply Wall Carbon Nanotubes, Ming-Qi Li

Journal of Electrochemistry

The electrochemical behavior of 3,4-Dihydroxybenzoic acid(DHBA)on modified multiply wall carbon nanotubes electrode was investigated by cyclic voltammetry(CV) and square wave voltammetry(SWV).Results show that in 0.1 mol/L HCl solutions the modified carbon nanotube electrode has an obvious electrocatalytic effect on the oxidation and deoxidization of DHBA.The oxidation current of DHBA is linear to it's concentration in the range of 4.0×10~(-6)~1.0×10~(-4) mol/L and 2.0×10~(-4)~8.0×10~(-4)1mol/L with correlation coefficient of 0.9995 and 0.9992.The detection limit is 1.0 ×10~(-6)mol/ L.


Silicides And Composites Materials As Anodes For Lithium Ion Batteries, Jun-Mei Yan Nov 2005

Silicides And Composites Materials As Anodes For Lithium Ion Batteries, Jun-Mei Yan

Journal of Electrochemistry

The anode materials of Mg_(2)Si and MnSi were synthesized by mechanically activated annealing(MAA) techniques in this work and the in electrochemical performances were also studied.A series of composite materials of Mg_(2)Si and CNTs or CMS were prepared by ball-milling method respectively.The reversible capacities of the composites were higher than that of the pure Mg_(2)Si and pure carbon materials.The cyclic performances have been improved greatly by ball-milling of the Mg_(2)Si and carbon materials.Results show that ball-milling method is one kind of method to make alloy materials into practical use.


Optimized Parameters For Electrochemical Fabrication Of P-Type Silicon-Based Two-Dimensional Photonic Crystals, Wan-Yun Zhang, Jia-Rong Ji, Xiao-Dong Yuan, Wei-Min Ye, Zhi-Hong Zhu Nov 2005

Optimized Parameters For Electrochemical Fabrication Of P-Type Silicon-Based Two-Dimensional Photonic Crystals, Wan-Yun Zhang, Jia-Rong Ji, Xiao-Dong Yuan, Wei-Min Ye, Zhi-Hong Zhu

Journal of Electrochemistry

A two-dimensional photonic band structure based on macroporous silicon with a gap centered at 20μm has been achieved for the first time.A medium doped p-type(100) silicon substrate was patterned by the standard photolithograpgy and alkaline efthing.And this pre-patterned sample was then etched 90 μm deep by electrochemical pore formation in the mixture of hydrofluoric-acid and dimethylformamide(DMF) to produce a quare lattice of circular air rods with a lattice constant of 3.8 μm and the very high aspect ratio up to 30.The optimized electrochemical parameters such as eletrolytical components and the current density were 5 % HF(by mass)+7 % H_(2)O(by mass)+DMF …


A Study Of Overcharge Characteristic Of Lithium-Ion Cells, Jing Pang, Shi-Gang Lu, Sha Liu Nov 2005

A Study Of Overcharge Characteristic Of Lithium-Ion Cells, Jing Pang, Shi-Gang Lu, Sha Liu

Journal of Electrochemistry

The overcharge characteristics and effect factors of lithium-ion cells containing LiMn_(2)O_(4)cathodes were studied in detail.Overcharge testing of Lithium-ion cells with a systematic variation in the cell balance demonstrated that the overcharge characteristics of Lithium-ion cells was affected by the amount of cathode in the cells,which is independent of the amount of anode material.The rate of charge was found to be an important parameter,as electrolyte complete decomposition at low charge rates caused the end of overcharge testing,while high charge rates accelerated the rate of heat generation in the cells and the cell temperature increased as a result of insufficient heat dissipation.The …


Electrochemical Oxidation Of Organic Additives In Tin Plating Electrolytes, Yin-Mei Cheng, Lan-Kun Cai, Qiang Song Nov 2005

Electrochemical Oxidation Of Organic Additives In Tin Plating Electrolytes, Yin-Mei Cheng, Lan-Kun Cai, Qiang Song

Journal of Electrochemistry

Cyclic voltammetry(CV) was used to characterize the voltammetric behaviours of organic additives,e.g.PSA(phenolsulfonic acid)、EN(ethoxylatedα-naphthol) and ENSA(ethoxylatedα-naphthol sulfonic acid),on the anode surface.In PSA solutions,an anodic peak was obtained and the peak potential was about 1.2V.In EN and ENSA solutions,two anodic peaks were obtained and the peak potentials were about(0.95V) and 1.3V.The products of galvanostatic electrolysis were separated by HPLC(high performance liquid chromatography) and analyzed by EI/MS(electron ionizing mass spectrometry).The mechnism of the electrochemical oxidation was also disussed.


Effects Of Aluminide And Platinum-Aluminide Coatings On The Hot Corrosion Behavior Of Mar-M247 Nickel-Based Superalloy, I.K. Lee Aug 2005

Effects Of Aluminide And Platinum-Aluminide Coatings On The Hot Corrosion Behavior Of Mar-M247 Nickel-Based Superalloy, I.K. Lee

Journal of Electrochemistry

This study is to investigate the high temperature hot corrosion behavior of aluminide coating and platinum-aluminide coating on Ni-base superalloy MAR-M247. On the platinum-aluminide, aluminide and the base metal, respectively, by the salt spraying method. The resistances to hot corrosion of platinum-aluminide coating, aluminide coating and the base metal were evaluated by the variations of weight gains. Aluminide and platinum-aluminide coating showed significanty beneficial effect on inhibiting the hot corrosion of MAR-M247. But that of the platinum-aluminide coating was even much better. The aluminide coating surface was composed of β-NiAl, and that of the platinum-aluminide coating was PtAl_(2). Both two …


The Growth Of Aluminide-Layer During The Hot-Dipping Al-(Si ) Coating Onto 430 Stainless Steels, Peng-Chicao Chen Aug 2005

The Growth Of Aluminide-Layer During The Hot-Dipping Al-(Si ) Coating Onto 430 Stainless Steels, Peng-Chicao Chen

Journal of Electrochemistry

The 430 stainless steels have been hot dipped in the molten Al-6.5%Si melts from 680 to 800℃, respectively. The effects of the hot dipping temperature and time on the thickness of the internal alloy layer have been investigated. The activation energy of the growth kinetic of aluminized layer was also calculated. The results showed that the thickness of aluminized layer increased with increasing dipping time and temperature. Besides, the growth kinetic of aluminized layer obeys parabolic rate law. The FeAl_(3 )and Fe_(2)Al_(5 )were formed by the inward diffusion, and the interface of intermetallic layer will be rugged and rough at …


Cyclic Voltammetry And Surface Enhanced Raman Spectroscopy Of Dissociative Adsorption Of Ethanol On Pt-Ru Electrodes, Zhang Bin Aug 2005

Cyclic Voltammetry And Surface Enhanced Raman Spectroscopy Of Dissociative Adsorption Of Ethanol On Pt-Ru Electrodes, Zhang Bin

Journal of Electrochemistry

The behaviors of dissociative adsorption of ethanol on roughened platinum-ruthenium electrode with high activity of SERS were studied by using cyclic voltammetry and in-situ surface enhanced Raman spectroscopy, surface enhanced Raman spectra of dissociative adsorption of ethanol on Pt electrode in acid was obtained for the first time. It is shown that the Pt-Ru could lower the over-potential of CO oxidation when compared to Pt electrode. The results show that the ethanol in acid medium can be self-dissociated at Pt-Ru electrode to produce CO, which discourage the further oxidation of ethanol, some information of Pt-C and Pt-C-Pt stretching vibration from …


Adsorption Of Polyaspartic Acid From Sulphur Acid Solution On Carbon Steel And Its Corrosion Inhibition, Rong-Jing Cui, Ning Gu, Chun-Mei Li Aug 2005

Adsorption Of Polyaspartic Acid From Sulphur Acid Solution On Carbon Steel And Its Corrosion Inhibition, Rong-Jing Cui, Ning Gu, Chun-Mei Li

Journal of Electrochemistry

The role of Polyaspartic acid in the corrosion inhibition of 45~(#) carbon steel in sulphuric acid solution has been investigated by polarization curve andelectrochemical impedance spectroscopy (EIS). The influences of the concentration and the temperature of PASP on the corrosion inhibition efficiency were determined. The results indicated that the PASP as the corrosion inhibitor mainly inhibitated the anode; within the experiment temperature, the inhibitor efficiency decreased with the raising of the temperature and PASP had a good inhibiting performance at 10℃, the corrosion inhibition efficiency of PASP for carbon steel increased with the increase of the concentration of PASP when …


Surface-Enhanced Raman Spectra Of Cytosine Adsorbed On A Roughened Gold Electrode, Yuan-Fei Wu, Jian-Feng Li, De-Yin Wu, Bin Ren, Zhong-Qun Tian Aug 2005

Surface-Enhanced Raman Spectra Of Cytosine Adsorbed On A Roughened Gold Electrode, Yuan-Fei Wu, Jian-Feng Li, De-Yin Wu, Bin Ren, Zhong-Qun Tian

Journal of Electrochemistry

Cytosine adsorbed on a roughened gold electrode has been investigated by using electrochemical cyclic voltammetry and surface-enhanced Raman spectroscopy (SERS). The results indicate that cytosine was adsorbed on the Au electrode in a perpendicular orientation via the N3 position. As the maximum enhancement of ring breathing mode appears at negative potentials compared with other modes, both the electromagnetic enhancement and the charge transfer mechanism were considered to contribute to the SERS intensity. The binding interaction between cytosine and the gold electrode was weakened when the potential was negatively moved. The result also indicates that the SERS technique can be used …


A Conjugate Dissolution / Deposition Behavior In Thin Layer Electrodeposition, Sun Bin Aug 2005

A Conjugate Dissolution / Deposition Behavior In Thin Layer Electrodeposition, Sun Bin

Journal of Electrochemistry

During the electrodeposition of lead, the dendrite deposit segregates from the cathode due to the disturbance of hydrogen gas. The segregated deposit could move toward the anode spontaneously rather than keep stationary. The studies show that this novel phenomenon was caused by the conjugate electrodissolution and electrodeposition reactions taking place at two ends of the isolated segment of the deposit. The mechanism inducing this phenomenon is suggested.


Corrosion Behavior Of Sml,Erw Pipeline Steels Exposed To Seamud, Wei Hua Aug 2005

Corrosion Behavior Of Sml,Erw Pipeline Steels Exposed To Seamud, Wei Hua

Journal of Electrochemistry

The corrosion behavior of API Spec X60 pipeline steels, including electric resistance welding(ERW) and Seamless (SML) types,in sea mud gathered fromYangtse River estuaryof the East China Sea was investigatedthrough linear polarization resistance, potentio-dynamic polarizationand electrochemical impedance measurements.The result indicate the improved corrosion resistance of SML in sea mud. The oxygen diffusion in the cathode zone determines the corrosion behavior of pipeline steel in sea mud.


Study On Theadsortionproperty Ofmdopd Onq235 Steel, Jin-Ying Huang, Jia-Shen Zheng Aug 2005

Study On Theadsortionproperty Ofmdopd Onq235 Steel, Jin-Ying Huang, Jia-Shen Zheng

Journal of Electrochemistry

The weight loss measurement, potentiodynamic polarisation curves, Electrochemical Impedance Spectroscopy and Atomic Force Microscopy were used to evaluate the corrosion inhibition performance of MDOPD in simulated oilfield water. At the same time, the adsorption mechanism of MDOPD on Q235 steels was suggested.The experimental results show the effective corrosion inhibition in the simulated oilfield water. The MDOPD possessesseveral nitrogen atoms as adsorption centres, which has higher active energy at metal surface and has more effective protection function.


Electrochemical Reduction Characteristics Of Nitrobenzene At The Copper Electrode, Jin-Hong Fan, Wen-Ying Xu, Ting-Yao Gao Aug 2005

Electrochemical Reduction Characteristics Of Nitrobenzene At The Copper Electrode, Jin-Hong Fan, Wen-Ying Xu, Ting-Yao Gao

Journal of Electrochemistry

The electrochemical reduction characteristics and transition steps of nitrobenzene aqueous solution at the copper electrode, as well as its reduction mechanism were extensively investigatedby using the techniques such as cyclic voltammetry(CV) and linear scan voltammetry(LSV). The results showed that the reduction peaks of nitrobenzene at the copper electrode were located at 0.58 V and 1.32 V or so (vs. SCE), both acidity and alkalinesolutionsfavoredthe reduction of nitrobenzene. The adsorption of compounds followed by the reduction process, which is controlled by the mass transfer step at higher nitrobenzene concentration. In addition, the higher anaerobic degree led to faster reduction rate.


5~(Th)Asian Conference On Electrochemistry, Acec2005 Held In Shanghai Aug 2005

5~(Th)Asian Conference On Electrochemistry, Acec2005 Held In Shanghai

Journal of Electrochemistry

No abstract provided.


The Application Of Astm C1202-93 On Evaluating The Performance Of Anti-Corrosion Of Concrete, Yuan Chen Yuan Aug 2005

The Application Of Astm C1202-93 On Evaluating The Performance Of Anti-Corrosion Of Concrete, Yuan Chen Yuan

Journal of Electrochemistry

The test of chloride ion penetration based on the standards of ASTM C1202-93 is applied to evaluate the anti-corrosion performance of concrete in this research. Concrete specimens were produced according to ACI 318-89 mixture proportioning design and the Desenfied Mixture Design Algorithm (DMDA) and were measured the 6-hour coulombs at the age of 91 days. Results show that w/b is not the factor influencing chloride penetration of ACI concrete, as the ion penetration of ACI specimens is all higher than 2 000 Coulombs and can even be poorer than 10 000 Coulombs. With a proper amount of pozzolanic material, the …


Electrocatalytic Oxidation And Degration Of Active Red X-3b By Nanotubes Catalytic Electrodes, Yi Wen, Jian-Hui Fang Aug 2005

Electrocatalytic Oxidation And Degration Of Active Red X-3b By Nanotubes Catalytic Electrodes, Yi Wen, Jian-Hui Fang

Journal of Electrochemistry

The catalytic splitting decomposition of carbon nanotubes isprocessed by dispersing with dilute nitric acid and thermal oxidation. Then well-proportionedphenolic resin is mixed in the carbon nanotubes. Then, the carbon nanotubesare made into electrodes by hot-press molding after the process of milling with high speed. The surface of the carbon nanotubes electrodes is analyzed by SEM. Active red X-3B simulated waster water is disposed by carbon nanotubes catalyticelectrode (anode) and stainless steel(cathode). The influencing factors of degradation by current density, concentrationof electrolyte, systemtemperature and pH are investigated. The experimental results indicated that acidiccondition is propitious tothe degradationreaction of organicdyestuff and wastewater …


Effect Of Sintering Temperatures On Synthesis Of Mgco_(0.4)Mn_(1.6)O_(4 ) Positive Materials In Magnesium Ion Battery, Xiu-Ling Gao, Li-Fang Jiao, Hua-Tang Yuan Aug 2005

Effect Of Sintering Temperatures On Synthesis Of Mgco_(0.4)Mn_(1.6)O_(4 ) Positive Materials In Magnesium Ion Battery, Xiu-Ling Gao, Li-Fang Jiao, Hua-Tang Yuan

Journal of Electrochemistry

The cathode material MgCo_(0.4)Mn_(1.6)O_(4 ) for magnesium ion battery was synthesized by sol-gel method. The TG-DTA and XRD analyses showed that the prepared samples has simple spinel structure. Effect of annealing temperature on electrochemical properties was researched.The result shows that the sample sintered at 700℃ has the best electrochemical properties.


Surface And Sructure Investigations Of Membrane Electrode Assembly In Dmfc Lifetime Testing~*, Chengxuan Chengxuan, Cheng Peng, Meng-Di You, Jing Liu, Ying Zhang Aug 2005

Surface And Sructure Investigations Of Membrane Electrode Assembly In Dmfc Lifetime Testing~*, Chengxuan Chengxuan, Cheng Peng, Meng-Di You, Jing Liu, Ying Zhang

Journal of Electrochemistry

The lifetime and performance of a direct methanol fuel cell (DMFC) were investigatedto understand the correlation between thestructure of catalysts /membrane and cell performanceversus time.The cell polarization and performance curves were obtained during the DMFC operation with the time.The catalysts and Nafion~ membrane of the membrane electrode assembly (MEA) from the lifetime test were comprehensively examined by XRD, HRTEM, FTIRand Raman spectroscope techniques.The results revealed that there was significant performance degradation during the first 200 hours operation; while the degradation was slowing down between 200 and 704hours operation.The degradation became worse after 1 002 h operation.The increases of the catalyst …


Research Progresses In A Flow Redox Battery, Quan-Feng Dong Aug 2005

Research Progresses In A Flow Redox Battery, Quan-Feng Dong

Journal of Electrochemistry

As a large scale electrochemical storage device, flow redox battery in which the active materials are flowing electrolytes is different from the common batteries employing solid or gas materials as an electrode. In this paper we introduced flow redox battery in brief, reviewed its development and actual state on (study). The main problem existed in the new device was discussed when viewed with its future developments.


Nafion Emulsion Method For Fuel Cell Membrane-Electrode-Assembly Preparation, Chao-Yang Xia, Lin Zhuang Aug 2005

Nafion Emulsion Method For Fuel Cell Membrane-Electrode-Assembly Preparation, Chao-Yang Xia, Lin Zhuang

Journal of Electrochemistry

A Nafion emulsion method for fuel cell membrane-electrode-assembly (MEA) preparation was reported for the first time in this paper. 5 %(by mass) Nafion alcohol solution and non-polar solvent (e.g., cyclohexane) were ultrasonicallymixed to produce Nafion emulsion. The catalyst ink prepared using the thus-obtained Nafion emulsion can be directly cast onto Nafion membrane to make MEA. This method is simple in operation, and effectively preventsthe Nafion membrane swelling, hence is suitable for large-scale application. The MEA thus-prepared showed comparable catalyst efficiencywith respect to the popular transfer-method, and the preliminary performance in room-temperature H_(2)/O_(2 )fuel cell test was satisfying.


A Preliminary Study Of Influence Of The Chain Length Of Alkanethiols On The Electrochemical Behavior Of Redox Self-Assembled Multilayer Thin Films, Yun-Feng Wang, Zhan-Jun Zhang Aug 2005

A Preliminary Study Of Influence Of The Chain Length Of Alkanethiols On The Electrochemical Behavior Of Redox Self-Assembled Multilayer Thin Films, Yun-Feng Wang, Zhan-Jun Zhang

Journal of Electrochemistry

Alkanethiols and ferrocene derivates were used to construct redox self-assembled double-or triplex-layer thin films, which acted as a model of redox self-assembled multilayer thin films (SAMTFs) to study the in-fluence of alkanethiols chain length on the electrochemical behavior of the SAMTFs. The rate of electron transferreaction decreased exponentially with the distance between the Fc groups and the underlying electrodes. The in-fluence of chain length on the electrochemical behaviors of the SAMTFs was inconsistent under different situa-tions. On the experimental situation of this work, when electroactive groups were closer to the electrodes,SAMTFs by longer chains of alkanethiols displayed stronger electrochemical responses, …


The Research Of Nano-Sized Nio Anode Materials For Lithium Ion Batteries, Jun-Mei Yan, Jing Zhang, Yong Yang Aug 2005

The Research Of Nano-Sized Nio Anode Materials For Lithium Ion Batteries, Jun-Mei Yan, Jing Zhang, Yong Yang

Journal of Electrochemistry

The nano-sized NiO materials were synthesized by solid phase method and sol-gel method. The synthesis conditions were optimized by DSC and TG techniques. The sol-gel method was optimized by changing the solvent and regulating the solution's pH for preparing NiO material. The structure and morphology of the materials were also characterized by means of XRD and TEM techniques, and the electrochemical performances of the materials were studied by the galvanostatically charge and discharge experiments.


An Electrochemical Behavior Of Limn_(2)O_(4) Electrode In Electrolyte Based On Room Temperature Ionic Liquid, Zheng Hong-He Aug 2005

An Electrochemical Behavior Of Limn_(2)O_(4) Electrode In Electrolyte Based On Room Temperature Ionic Liquid, Zheng Hong-He

Journal of Electrochemistry

The electrochemical behavior of spinel LiMn_(2)O_(4)electrode in ionic liquid electrolyte was investigated by using cyclic voltammetry, galvanostatic charge-discharge and ACimpedance techniques. The results reveal that the spinel LiMn_(2)O_(4)can be effectively cycled in electrolyte based on the ionic liquid with discharge capacity of 108.2mAh/g and Coulombic efficiency of more than 90% in the first cycle at room temperature. Temperature and current density play an important role in the electrode performances. The activation energy for lithium ion transfer through interface between the electrode and the electrolyte was evaluated by AC impedance spectroscopy. The high activation energy accounts for the poor cell performance …


Investigation, On The Accelerated Dissolution Of Metal Induced By Afm Tip Scratching And Suppressed By Inhibitors, Jun-E Qu, Xing-Peng Guo Aug 2005

Investigation, On The Accelerated Dissolution Of Metal Induced By Afm Tip Scratching And Suppressed By Inhibitors, Jun-E Qu, Xing-Peng Guo

Journal of Electrochemistry

The accelerated dissolution behavior of Cu-Ni alloy induced by AFM tip scratching and the inhibition effect of corrosion inhibitors were investigated. The results showedthat, with a tip loading of 750nN ,continuous scan for 30 min in a contact mode on 4×4 μm~(2) of copper-nickel alloy in 1.5mol/L NaCl and 0.01mol/L HCl could enhance the dissolution of the sample and produced pits on the scratched area. Adding inorganic inhibitors, sodium chromateand organic inhibitor dodecylamine, to the solution suppressed the dissolution of copper-nickel alloyinduced by tip scratching, respectively, by improving the surface passivationperformance of metal surface and forming adsorption films on copper-nickel …


Effect Of Chloride Ions On The Corrosion Behavior Of Reinforcing Steel In Simulated Concrete Pore Solutions, Yu Liu, Rong-Gui Du Aug 2005

Effect Of Chloride Ions On The Corrosion Behavior Of Reinforcing Steel In Simulated Concrete Pore Solutions, Yu Liu, Rong-Gui Du

Journal of Electrochemistry

The potentiodynamic anodic polarization was used to study the corrosion behavior of the reinforcing steel in simulated concrete pore solutions with different pH and chloride ion concentrations. The effect of chloride ions on passivity breakdown of the steel was examined by measuring the breaking potentials of reinforcing steel, and the critical chloride concentrations for depassivation were found in simulated concrete pore solutions at pH 12.50 and pH 12.00.


Electrochemical Behavior And Determination Of Curcumin, Ping Wu, Wei Chen, Ya-Feng Zhang, Xin-Hua Lin Aug 2005

Electrochemical Behavior And Determination Of Curcumin, Ping Wu, Wei Chen, Ya-Feng Zhang, Xin-Hua Lin

Journal of Electrochemistry

In 0.1mol/L phosphate buffer solution (pH 3.0), the voltammetry behaviors of curcumin at a glassy carbon electrode have been studied.One pair of current peaks of the voltammogram may be attributed to a reversible one-electron transfer of curcumin molecules at the glassy carbon electrode.A new method, the differential pulse voltammetry,for curcumin determination is described. The adsorptive potential of curcumin is (+0.8) V(vs. SCE),while its peak potential of curcumin is +0.386V(vs. SCE).The peak current is proportional to the concentration of curcumin over the rage of 1.0×10~(-8)mol/L ~2.5×10~(-7)mol/L.A detection limit of 4.0×10~(-9)mol/Lof curcumin can be estimated. The method is simple, rapid, sensitive and …


Study On The New Type Fe_3o_4 Composite Anode, Xiongxin-Yong Xiongxin-Yong May 2005

Study On The New Type Fe_3o_4 Composite Anode, Xiongxin-Yong Xiongxin-Yong

Journal of Electrochemistry

An ultrafine powder of magnetite has been prepared, and used to prepare the composite anode of Fe_(3)O_(4)-Fe by sintering method. The voltage of chlorine evolution、polarization curves、service life and mass loss, and the optimum sintering temperature and the weight ratio of the sintered powder have been investigated. All results showed that the method of preparing the practical Fe_(3)O_(4)-Fe composite uniform anode is feasible.