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Full-Text Articles in Engineering

Electrochemical Oxidization Of Herring Sperm Dna And Its Interaction With Histone, Juan Xu, Gui-Ping Huang, Hong Li, Wei Zhu Nov 2007

Electrochemical Oxidization Of Herring Sperm Dna And Its Interaction With Histone, Juan Xu, Gui-Ping Huang, Hong Li, Wei Zhu

Journal of Electrochemistry

The voltammetric behavior of herring sperm DNA at glassy carbon electrode and its interaction with histone have been investigated by using cyclic voltammetry,differential pulse voltammetry,and fluorescence measurement.In the potential range of 0.20 V to 1.25 V,it is found that an irreversible oxidative peak is exhibited in acid solution,but in the neutral or alkaline solution two oxidative peaks are observed.Oxidative peak potential values show a negative shift with increasing pH via a slope of-57 mV·pH-1 and a linear relation with DNA concentration in the range of 0.45 to 8.20 mmol·L-1.In the presence of histone,the oxidative peak current of DNA and the …


Eiectro-Oxidation Of Methanol On Pdnio/C Catalyst In Alkaline Medium, Mei-Li Wang, Lin Sang, Cheng-De Huang Nov 2007

Eiectro-Oxidation Of Methanol On Pdnio/C Catalyst In Alkaline Medium, Mei-Li Wang, Lin Sang, Cheng-De Huang

Journal of Electrochemistry

The electro-oxidation of methanol in alkaline electrolyte at in-house synthesized PdNiO/C and Pd/C catalysts and the effect of heat treatment on the structure and performance of catalysts were studied by cyclic voltammetry,chronoamperometry,chronopotentiometry and X-ray diffraction methods.It is shown that when the reduction temperature is 70℃ and the ratio between Pd and Ni is 8∶2,The PdNiO/C catalyst presents a highest activity for methanol electrooxidation.Calcining can increase the particle size and crystallinity of catalysts,but decrease the dispersion and activity of catalysts, too.Besides,the NiO is disengaged from Pd lattice by heat-treatment.The optimal PdNiO/C catalyst shows higher catalytic activity and much better poisoning resistance …


Selection Of Additions In The Process Of Electrochemical Synthesizing Of K_2feo_4, Wei-Hua Yang, Dong-Qin Bi, Yan Zhou, Hong-Hui Wang, Xin-Ren Lan Nov 2007

Selection Of Additions In The Process Of Electrochemical Synthesizing Of K_2feo_4, Wei-Hua Yang, Dong-Qin Bi, Yan Zhou, Hong-Hui Wang, Xin-Ren Lan

Journal of Electrochemistry

Some of different additions including KIO4 was added to the anodic electrolyte for electrochemical synthesizing of K2FeO4,the effects of these additions on current yield were investigated.XRD and SEM were used to characterize the structure and image of K2FeO4.The results show that KIO4 is a preferable addition.When the mass dosage of KIO4 is 0.02%,electrolysis time is 1 h,the current yield is enhanced by 31.6% and the corresponding purity of the product is improved by 3.85 %.


Ion-Implanting Modification Of Layered Manganese Dioxide And Its Electrochemical Performance, He-Ning Huang, Dong-Ping Lv, Xing-Kang Huang, Qi-Wei Zhang, Yong Yang Nov 2007

Ion-Implanting Modification Of Layered Manganese Dioxide And Its Electrochemical Performance, He-Ning Huang, Dong-Ping Lv, Xing-Kang Huang, Qi-Wei Zhang, Yong Yang

Journal of Electrochemistry

Layered MnO2(δ-MnO2) was prepared by thermal decomposition of potassium permanganate.Ti was ion-implanted into such δ-MnO2 by physical techniques,forming a composite(δ-MnO2-Ti).These materials were characterized by XRD,SEM,XPS techniques and their electrochemical proprieties were investigated.The results showed that the layered structure of δ-MnO2 did not been destroyed after Ti ion implantation,and the implanted Ti element was mainly Ti4+ as indicated by XPS.Both of the first and the highest discharge specific capacities of the ion-implanted layered MnO2(δ-MnO2-Ti),compared to those of δ-MnO2,were improved significantly.


The Syntheses And Electrochemical Performance Of Nano-Mno_2 For Supercapacitor, Jun Ma, Ming-Sen Zheng, Quan-Feng Dong Aug 2007

The Syntheses And Electrochemical Performance Of Nano-Mno_2 For Supercapacitor, Jun Ma, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

Nano-manganese dioxide were prepared by two different methods which are low temperature solid reaction and chemical deposition.The products were characterized by XRD,SEM,BET and constant current charge-discharge tests.The result shows that there is a close relationship between specific capacitance and BET surface areas.Meanwhile the specific capacitance was impacted little by the structure of the nano-manganese dioxides.However,the product performance of high rates,was influenced by structure,the higher rate can be obtained with the more perfect crystal structure.


Preparation,Structure,And Cv Study Of The Supported Ptruir/Tic Electrocatalysts For Oxygen Electrodes, Sheng Sui, Li-Rong Ma Aug 2007

Preparation,Structure,And Cv Study Of The Supported Ptruir/Tic Electrocatalysts For Oxygen Electrodes, Sheng Sui, Li-Rong Ma

Journal of Electrochemistry

The PtRuIr/TiC electrocatalysts were prepared by method of reduction and deposition on TiC powders as supports together with ultrasonic wave dispersion.The sampls were characterized by BET surface area,scanning electron microscope,X-ray diffraction,and cyclic voltammetry techniques.The active components of Pt,Ru,and Ir particles(2.6%Pt,1.3%Ru,16%Ir,and 80%TiC,by mass) were mainly dispersed on the outer surface of the TiC supports,which structures were in favor of fine variable crystallites.It was found that the electrochemical performance of the PtRuIr/TiC electrodes was about three times as that of the unsupported electrocatalysts with the same active compositions for oxygen evolution reaction.After 120 times of CV cycles,there was almost no PtRuIr/TiC dissolving …


Electro-Chemical Oxidation Kinetics Of The V(Iv) In The Sulfuric Acid Solution, Yong-Lian Qiao, Qian Xu, Jie Zhang, Yu-Chun Zhai Aug 2007

Electro-Chemical Oxidation Kinetics Of The V(Iv) In The Sulfuric Acid Solution, Yong-Lian Qiao, Qian Xu, Jie Zhang, Yu-Chun Zhai

Journal of Electrochemistry

The electro-chemical oxidation kinetics for V(IV) in the sulfuric acid solution were investigated by cyclic voltammetry and steady state polarization curves at a graphite,platinum or conducting polymer electrode.Some kinetics parameters for the electrochemical reaction of V(IV) were calculated according to the Tafel curves.The results showed that the exchange current density and reversibility of V(V)/V(IV) redox reaction at the graphite electrode is largest among the three electrodes.There is the broadest extent of water stability and large oxidgen evolution potential when the conducting polymer was used as a working electrode in the solution of VOSO4(0.5 mol/L) and H2SO4(2 mol/L),while it is easy …


Oxygen Enrichment Effect Of Mno_2-Pt/C Compound Catalyst To The Cathode Of Pemfc, Hong-Feng Xu, Mao-Feng Zhang, Quan-Quan Gan, Cai-Sheng Huang Aug 2007

Oxygen Enrichment Effect Of Mno_2-Pt/C Compound Catalyst To The Cathode Of Pemfc, Hong-Feng Xu, Mao-Feng Zhang, Quan-Quan Gan, Cai-Sheng Huang

Journal of Electrochemistry

TO study of the oxygen storage material of air cathode is crucial for increasing performance of proton exchange membrane fuel cell.Using the MnO2 as oxygen storage materials,a MnO2-Pt/C catalysts were prepared and is used to replace the conventional Pt/C in air cathode.The electrochemical performance of air cathode composed of MnO2 supported on Pt/C and the properties of fuel cell composed of MnO2-Pt/C were investigated by using the CV,galvanostatic dischange method and TEM.


Electrocatalytic Oxidation Of Methanol At The Nano Ni-B Amorphous Alloy Powdermicroelectrode, Yi-Xiong Zheng, Shi-Bing Yao, Shao-Min Zhou Aug 2007

Electrocatalytic Oxidation Of Methanol At The Nano Ni-B Amorphous Alloy Powdermicroelectrode, Yi-Xiong Zheng, Shi-Bing Yao, Shao-Min Zhou

Journal of Electrochemistry

Electrocatalytic oxidation of methanol at the nano Ni-B amorphous alloy powder-microelectrode in alkaline media was studied by using cyclic voltammetry.Compared to the highly preferred orientation(220) nickel electrode,The onset potential of methanol electrooxidation at the nano Ni-B microelectrode is negatively shifted about 0.04V,and the current density is increased approximately by 2 orders of magnitude.Thus,the nano Ni-B microelectrode has very strong electrocatalytic activity for the oxidation of methanol.The kinetic parameters were determined with the steady polarization curves.The results show that the rate constants for both the oxidation of Ni(Ⅱ) to Ni(Ⅲ) and the reduction of Ni(Ⅲ) to Ni(Ⅱ) at the nano Ni-B …


Electricity Generation From A Microbial Fuel Cell Employing Desulfovibrio Salexigens, Ping Ding, Hai-Bo Shao, Guang-Zhou Liu, Dong-Xia Duan, Ting Ma, Si-Jun Chen, Jian-Ming Wang, Jian-Qing Zhang May 2007

Electricity Generation From A Microbial Fuel Cell Employing Desulfovibrio Salexigens, Ping Ding, Hai-Bo Shao, Guang-Zhou Liu, Dong-Xia Duan, Ting Ma, Si-Jun Chen, Jian-Ming Wang, Jian-Qing Zhang

Journal of Electrochemistry

A microbial fuel cell of laboratory scale employing Desulfovibrio salexigens in lactate based seawater substrate was proposed.Electricity was continuously harvested after inoculation.During 20 days of fermentation/discharge,COD values of the substrate decreased by 61.7%,in which 9.81% was converted to electricity.


Electrochemical Performance Of Li_(1-X)M_Xfepo_4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai May 2007

Electrochemical Performance Of Li_(1-X)M_Xfepo_4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai

Journal of Electrochemistry

Olivine Li1-xMxFePO4(M=Cr3+、Mg2+、Mn2+、Ni2+)were synthesized by a polyacrylates-pyrolysis route.The structural and electrochemical properties of the as-synthesized cathode materials were investigated by powder X-ray diffraction(XRD),scanning electron microscopy(SEM),and electrochemical charge/discharge cycling.The results indicate that the metallic ions doped at low concentration do not affect the crystalline structure of the material,but considerably improve the rate capability and cycle performance of LiFePO4 at high rate.


Template Synthesis And Electrochemical Studies Of Ag_(Core)Au_(Shell) Nanowires, Li Ling, Ya-Xian Yuan, Min-Min Xu, Jian-Lin Yao, Ren-Ao Gu May 2007

Template Synthesis And Electrochemical Studies Of Ag_(Core)Au_(Shell) Nanowires, Li Ling, Ya-Xian Yuan, Min-Min Xu, Jian-Lin Yao, Ren-Ao Gu

Journal of Electrochemistry

Agcore Aushell nanowires with different thicknesses were prepared by combining template synthesis and chemical reduction method,and characterized by SEM and cyclic voltammetry(CV).The CV results revealed that the AgcoreAushell nanowires with pinhole were transferred to pinhole free structure after several potential scans.By using thiophenol(TP)and p-aminothiophenol(PATP)as probe,the surface enhanced Raman scattering(SERS)effect was investigated on the core-shell nanowires.The results indicated that AgcoreAushell nanowires could be served as a potential SERS substrate,and the difference in the spectral feature of PATP adsorbed onto Au and Ag nanowires enable us to diagnose the pinhole effect of core-shell nanowires by SERS.


Electrochemical Reduction Of Coals And The Oxygenic Functional Simulacrums Of Coals, Juan Lin, Zhao Wei May 2007

Electrochemical Reduction Of Coals And The Oxygenic Functional Simulacrums Of Coals, Juan Lin, Zhao Wei

Journal of Electrochemistry

Electrochemical reduction of coals and the oxygenic functional simulacrums of coals has been studied.In this process,tetrabutylammonium was used as supporting electrolyte.The coal and the deoxidized coal were extracted by methanol.Qualitative analysis of the deoxidized products and the extractives was carried out on gas chromatograph-mass spectrometer.The deoxidized products of the oxygenic functional simulacrums of coals were analysed quantitatively with gas chromatograph spectrometer.The results show that the oxygenic functional groups on the coals surface decrease and the translation ratios of the oxygenic functional simulacrums of coals need further increase after electrochemical reduction,.The electrochemical tests show simultaneously the kinetics equations of every related …


Catalysis Of Nano Tio_2 For Horseradish Peroxidase, Ya-Qi Zhu, Hai Wu, Hiu Liu, Jie Ma May 2007

Catalysis Of Nano Tio_2 For Horseradish Peroxidase, Ya-Qi Zhu, Hai Wu, Hiu Liu, Jie Ma

Journal of Electrochemistry

Horseradish peroxidase immobilized on the surface of titanium dioxide nanoparticles and nanotube modified glassy carbon electrode.The HRP direct electron transfer reaction was compared between TiO2 nanoparticles and nanotube GC electrode.The results demonstrated that the HRP on TiO2 nanotube /GC electrode could catalyze electron exchange reaction between electroactivity center of HRP and electrode.And the research of antibody labeled HRP provides a selected signal for antibody-antigen immunoassay.


Modification Of Electrolytic Manganese Dioxide, Shu-Rong Ding, Xin-Hai Li, Zhi-Xing Wang, Hua-Jun Guo May 2007

Modification Of Electrolytic Manganese Dioxide, Shu-Rong Ding, Xin-Hai Li, Zhi-Xing Wang, Hua-Jun Guo

Journal of Electrochemistry

The EMD samples coated with CMD-Bi compound were prepared by liquid-phase surface treatment method.XRD and SEM research indicated that the modified manganese dioxide,i.e,EMD/CMD-Bi,could keep γ-MnO2 crystal structure of EMD and had more pores on its surface with an obvious floccule layer.Electrochemical test indicated that the second electron reduction peak current increased by 1.5 times and the discharge capacity increased by 40.8% and 78.3% respectively than that of pure EMD electrode under the condition of-0.8 V(vs.Hg/HgO)cut-off voltage at 30.8 mA/g and 102.7 mA/g current density.


Study On The Electrogeneration And Properties Of Superoxide Ion In Aprotic Media By Using Carbon Nanotubes Powder Microelectrode, Ying-Liang Wei, Chen Shao, Hui Feng May 2007

Study On The Electrogeneration And Properties Of Superoxide Ion In Aprotic Media By Using Carbon Nanotubes Powder Microelectrode, Ying-Liang Wei, Chen Shao, Hui Feng

Journal of Electrochemistry

Multi-wall carbon nanotubes are filled in the cavity at the tip of a microelectrode to form a carbon nanotubes powder microelectrode(CNTs-PME).The CNTs-PME is used to study the electrochemical reduction of oxygen in aprotic media.It is a nearly reversible redox process of the O2/O·-2 couple at the CNTs-PME in the dimethyl sulfoxide(DMSO)solution.The heterogeneous electron transfer rate constant(ks)can be measured by steady-state voltammogram and the result is 9.8 10-3cm /s.As a weak oxidant,the reaction of O·-2 with epinephrine was studied by cyclic voltammetry.Additionally,the reaction of O·-2 with benzoic acid was also discussed in detail.


Electrochemical Oxidation Of The Phenol In The Chloride System, Yong Liu, Dan Liu, Shi-Lin Zhao, Jing-Jing Lai Feb 2007

Electrochemical Oxidation Of The Phenol In The Chloride System, Yong Liu, Dan Liu, Shi-Lin Zhao, Jing-Jing Lai

Journal of Electrochemistry

The Ru-Ir /Ti electrode as cathode to electrolysis the synthetic phenolic wastewater was studied.The effect of the initial chloride concentration on the electrolytic treatment result has been discussed.Experiment result shows that the electrochemical oxidation of phenol suits to one kinetics equation in given electrolytic time.If the initial chloride concentration in wastewater increases,the time of the electrochemical oxidation of phenol can be shorten,in other words the apparent rate constant is greater.the middle matters of electrochemical oxidation of phenol in the chloride system detected out by HPLC and GC-MS is mainly 1-chloro-phenol,4-chloro-phenol,2,4-dichloro-phenol,2,6-dichloro-phenol,2,4,6-trichloro-phenol,all kinds of chlorohydrin,small aliphatic acid,and so on.The final production is …


Mwnts Modified Gc Electrode For Hydrogen Peroxide Determination, Hong-Juan Wang, Chun-Mei Zhou, Hao Yu, Feng Peng, Jin-Kun Fang Feb 2007

Mwnts Modified Gc Electrode For Hydrogen Peroxide Determination, Hong-Juan Wang, Chun-Mei Zhou, Hao Yu, Feng Peng, Jin-Kun Fang

Journal of Electrochemistry

A MWNTs modified GC electrode was constructed successfully to be used to detect hydrogen peroxide.Two methods of maximum anodic current of cyclic voltommogram and chronoamperometry were adopted to measure the concentration of hydrogen peroxide.The results show that the MWCNTs can enlarge the effective surface area of GC electrode and can enormously enhance the electron transfer.The sensitivity and correlation coefficient for hydrogen peroxide detection are 2.84 μA/mmol·L-1,0.997 and 1.5 μA/mmol·L-1,0.971 for cyclic voltammetry and chronoamperometry,respectively.The procedure of the two methods to detect hydrogen peroxide is simple,and the results obtained are satisfied.


The Influence Of Electrolytic Conditions On Synthesis Of Feo_4~(2-), Yan Zhou, Wei-Hua Yang, Dong-Qin Bi, Ting-Ting Huang, Zhen Sun, Quan-Feng Guo Feb 2007

The Influence Of Electrolytic Conditions On Synthesis Of Feo_4~(2-), Yan Zhou, Wei-Hua Yang, Dong-Qin Bi, Ting-Ting Huang, Zhen Sun, Quan-Feng Guo

Journal of Electrochemistry

The FeO42-was synthesized using iron lattice as anode and the solid K2FeO4 was also prepared.Influence of electrolytic conditions,such as stir,ultrasonic,temperature and current density on the current efficiency were studied.The results showed that preferable ferrate(VI) current yield was obtained in a current density of 10 mA·cm-2,temperature 30℃ and 14 mol/L NaOH as electrolyte under at stirring effect.


Fabrication And Performance Of Ni-Scsz Cermet Anode Modified By Coating With Gd_(0.2)Ce_(0.8)O_2 For A Sofc, Ren-Zhu Liu, Bo Huang, Xiao-Feng Ye, Shao-Rong Wang, Jia-Di Cao, Huai-Wen Nie, Ting-Lian Wen Feb 2007

Fabrication And Performance Of Ni-Scsz Cermet Anode Modified By Coating With Gd_(0.2)Ce_(0.8)O_2 For A Sofc, Ren-Zhu Liu, Bo Huang, Xiao-Feng Ye, Shao-Rong Wang, Jia-Di Cao, Huai-Wen Nie, Ting-Lian Wen

Journal of Electrochemistry

A Ni-scandia-stabilized zirconia(Ni-ScSZ) cermet anode modified by coating with nano-sized gadolinium-doped ceria(GDC,Gd0.2Ce0.8O2) was prepared using a simple combustion process for the solid oxide fuel cell(SOFC) running on methane fuel.X-ray diffraction(XRD) and scanning electron microscopy(SEM) indicated that the surface of Ni-ScSZ was coated by nano-sized GDC particles(<100nm).Single cell testing showed that the 2.0%(by mass) GDC-coated Ni-ScSZ anode had better performance.The highest power densities of the cell with this anode were 825 and 848mW/cm2 at 850℃ in humidified hydrogen and methane,respectively,whereas the corresponding values were 584 and 586mW/cm2 for the cell with Ni-ScSZ anode.Electrochemical impedance spectra(EIS) illustrated that the cell with Ni-ScSZ anode exhibited far greater impedances than the cell with 2.0%(by mass) GDC-coated Ni-ScSZ anode.Then the short-term stability for the cells with the Ni-ScSZ and 2.0%(by mass) GDC-coated Ni-ScSZ anodes in 97%CH4/3%H2O at 700℃ was checked over a relative long period of operation.No significant degradation in performance has been observed after 84 h of cell testing when 2.0%(by mass) GDC-coated Ni-ScSZ anode was exposed to 97%CH4/3%H2O at 700 ℃.Very little carbon was detected on the anodes,suggesting that carbon deposition was limited during cell operation.