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Full-Text Articles in Engineering

Electrochemical Reduction Behavior Of Benzaldehyde In The Ionic Liquids, Ning Zhao, Wen-Ju Dong Feb 2006

Electrochemical Reduction Behavior Of Benzaldehyde In The Ionic Liquids, Ning Zhao, Wen-Ju Dong

Journal of Electrochemistry

In this paper,the electrochemical reduction of benzaldehyde was investigated in C_4MIMBF_(4)、(C_(6)MIMBF_(4)) and C_(8)MIMBF_(4) ionic liquids by cyclic linear sweep voltammetry,cyclic square-wave voltammetry and chronocoulometry.Benzaldehyde exhibits two successive one-electron irreversible reduction(E_(P1)=-1.39 V,E_(P2)=1.69 V) with GC electrode in C_(4)MIMBF_(4),the voltammetric data for benzaldehyde give diffusion coefficients of 1.5 10~(-8)cm~(2)/s and 1.3 10~(8)cm~2/s.There is one current peak in C_(6)MIMBF_(4)and C_8MIMBF_4 ionic liquids due to their stronger alkalinity then C_4MIMBF_4.The decay time of the charging current became longer in C_(4)MIMBF_(4)、C_(6)MIMBF_(4)、C_(8)MIMBF_(4),and slower heterogeneous kinetics in(C_(6)MIMBF_(4)) and C_(8)MIMBF_(4) ionic liquids.


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.


Application Of Carbon Paste Electrode On The Electrogenerative-Leaching Process Of Sulfide Minerals, Shao-Fen Wang Feb 2005

Application Of Carbon Paste Electrode On The Electrogenerative-Leaching Process Of Sulfide Minerals, Shao-Fen Wang

Journal of Electrochemistry

The cyclic voltammetry curves of sulfide mineral electrodes or corresponding carbon paste electrodes in NaCl electrolytes have been obtained in this study. The experimental results indicate that acetylene black (revealed) the electro-catalytic propertyin the electrogenerative-leaching process of sulfide minerals. The output currentand potential of carbon paste electrodes were increased to some degrees while the activation energies were lower.


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 …


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 …


Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin Nov 2002

Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin

Journal of Electrochemistry

Metallic nickel was electrochemically dissolved in absolute ethanol and acetylacetone mixed solutions and in the presence of Bu 4NBr (as an electron-conductive additive). The electrolyte solution containing the precursor was then directly hydrolyzed to obtain nanocrystalline NiO. The precursor was characterized by FTIR?HNMR?Raman spectra and the nano-powder was characterized by XRD and TEM. The results showed that the NiO powder after calcined at 450 ℃ had formed the cubic NaCl structure and the nanocrystalline NiO prepared by this method had narrow size distribution of 10~15 nm. Moreover, the product yield could be improved by controlling temperature below 30~40 ℃. The …


Electrochemical Evaluation On The Porosity Of Electroless Ni-P Alloy Coatings, Hong-Ying Yu, Dong-Bai Sun, Jing-Bing Huang, De-Jun Yang Aug 2000

Electrochemical Evaluation On The Porosity Of Electroless Ni-P Alloy Coatings, Hong-Ying Yu, Dong-Bai Sun, Jing-Bing Huang, De-Jun Yang

Journal of Electrochemistry

By investigating the polarization curves of pure Ni P alloy,Ni P alloy coation and carbon steel in nitric acids with different concentrations,the sutable concentration of nitric acid for the evaluation of the porosity of Ni P alloy coatings has been determined and the coatings with different thickness have been evaluated.The results indicated that the nitric acid with 10 wt% concentration is the most suitable solution for the porosity of the coating by using electrochemical method.The polarization curve of Ni P alloy coating in 10% nitric acid can accurately reveal the porosity.With the decrease of the porosity of the coating,the corrosion …


A Study On Stochastic Resonance For The Process Of Active-Passive Transition Of Iron In Sulfuric Acid, Hong Bo Ding, Bao Yun Xia, Chun Sheng Yin, Zhong Xiao Pan Aug 2000

A Study On Stochastic Resonance For The Process Of Active-Passive Transition Of Iron In Sulfuric Acid, Hong Bo Ding, Bao Yun Xia, Chun Sheng Yin, Zhong Xiao Pan

Journal of Electrochemistry

The bistable characteristics of the process of active passive transition of iron in sulfuric acid was described and the stochastic resonance phenomenon in the process was simulated.


Effect Of Inhibitor On Electrochemical Behavior Of 1cr18 Stainless Steel In Acidic Solution Under Friction, Jinping Xiong May 1999

Effect Of Inhibitor On Electrochemical Behavior Of 1cr18 Stainless Steel In Acidic Solution Under Friction, Jinping Xiong

Journal of Electrochemistry

The electrochemical behavior of 1Cr18 stainless steel had been studied using a reciprocating triboelectrochemical equipment under friction in 0.2 mol/L H2SO4 solution with and without addition of thiourea, the frictionized surface of 1Cr18 stainless steel had been examined by the SEM, XPS and IR. The results showed that the loss rate of 1Cr18 stainless steel in the solution could be reduced by addition of thiourea. The adsorption of thiourea on the surface of 1Cr18 stainless steel prohibited the oxidization of Cr3+ to form Cr() and formation of passive film consisting of CrO42- or/and Cr(), and make the passive range to …


Self-Assembled Monolayers:Preparation,Properties And Application, Xiandui Dong, Juntao Lu, Chuansin Cha Aug 1995

Self-Assembled Monolayers:Preparation,Properties And Application, Xiandui Dong, Juntao Lu, Chuansin Cha

Journal of Electrochemistry

Self-assembling technique is a versatile approach to the preparation of monolayersof well-defined composition,structure,thickness and physicochemical properties.Different aspects,such as wettability,adhesion,corrosion,tribology,electrontransfer,protein adsorption,molecularrecognition,and applications of SAMs are widely studied.The developments in the last decade arereviewed,with special attention to the electrochemical studies related to electrodes modified with thiol-derivative-based SAMs