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Full-Text Articles in Physical Sciences and Mathematics

Recent Experimental Progresses On Electrochemical Atr-Seiras, Yao-Yue Yang, Han-Xuan Zhang, Wen-Bin Cai Feb 2013

Recent Experimental Progresses On Electrochemical Atr-Seiras, Yao-Yue Yang, Han-Xuan Zhang, Wen-Bin Cai

Journal of Electrochemistry

Technical aspects on developing electrochemical ATR surface-enhanced infrared absorption spectroscopy are briefly accounted mainly based on our recent investigations, including wet-fabrication of metallic film electrodes on Si prism, design and construction of a wide-frequency combination optical window and a spectroelectrochemical cell switchable for external and internal reflection modes.


Combination And Applications Of Time-Resolved Surface Plasmon Resonance Spectroscopy And Electrochemical Methods, Yu Bao, Yan Mao, Wei Wang, Zheng-Gang Li, Li Niu Feb 2013

Combination And Applications Of Time-Resolved Surface Plasmon Resonance Spectroscopy And Electrochemical Methods, Yu Bao, Yan Mao, Wei Wang, Zheng-Gang Li, Li Niu

Journal of Electrochemistry

Electrochemical-surface plasmon resonance (EC-SPR) technique, developed in recent years, is a new technology which combines time-resolved surface plasmon resonance spectroscopy and electrochemical methods. Surface plasmon resonance (SPR) is a physical phenomenon generated by optical coupling using a metallic thin film and is very sensitive to optical analysis. The principles of SPR and EC-SPR are briefly introduced and the applications of the combination of SPR spectroscopy with electrochemical techniques are reviewed in this paper. This new technology has been widely used in such research areas as reaction dynamics, biochemical sensors, electrode/electrolyte interfaces, kinetic parameters and bimolecular interactions.


Spectral, Electrochemical, Luminescence, And Dye-Sensitized Solar Cell Studies Of Mono And D-F Hetero Binuclear Cryptates, Arunachalam Vijayaraj, Raju Prabu, Ranganathan Suresh, Subbaiah Manoharan, Sambandam Anandan, Vengidusamy Narayanan Jan 2013

Spectral, Electrochemical, Luminescence, And Dye-Sensitized Solar Cell Studies Of Mono And D-F Hetero Binuclear Cryptates, Arunachalam Vijayaraj, Raju Prabu, Ranganathan Suresh, Subbaiah Manoharan, Sambandam Anandan, Vengidusamy Narayanan

Turkish Journal of Chemistry

Mono and hetero binuclear cryptates, [Gd(III)ML]^+ [M = VO(IV), Co(II), Ni(II), Cu(II)], were synthesized by a 2-step method. The ligand L represents the deprotonated anionic cryptate obtained by the 2+3 condensation of tris-(2-aminoethyl)amine with 2,6-diformyl-4-nitrophenol. The complexes were characterized by elemental analysis, spectral, magnetic, and electrochemical studies. Fluorescence of Gd(III) ion in the cavity was quenched by the encapsulated Cu(II) and Ni(II) ions. [GdCoL(NO_3)]^+ cryptate had a high lifetime value compared to other cryptates. The cyclic voltammogram showed that the reduction potential values of [Gd(M)L] M = VO(IV), Co(II), Ni(II), and Cu(II) complexes were in the following order: Cu(II) > Ni(II) …


Novel Molten-Salt Electrolysis Processes Towards Low-Carbon Metallurgy, Wei Xiao, Hua Zhu, Hua-Yi Yin, De-Hua Wang Jun 2012

Novel Molten-Salt Electrolysis Processes Towards Low-Carbon Metallurgy, Wei Xiao, Hua Zhu, Hua-Yi Yin, De-Hua Wang

Journal of Electrochemistry

This review focuses on recent developments in molten-salt electrolytic metallurgical processes with respect to 1) high-efficiency metallurgical technologies via electrolytic reduction of solid oxides in molten chlorides and 2) zero-carbon-footprint electrochemical splitting metallurgical technologies. Initiating with an introduction on dynamic solid/solid/liquid three-phrase interlines electrochemistry for electrochemical reduction of solid cathode, the former aspect is discussed in terms of facilitating mass transfer throughout solid cathode, one-step production of functional alloy powders with the assistance of under-potential electroreduction of active metals and near-net-shape production of metal/alloy components. Whilst the latter is summarized by introducing some zero-carbon molten-salt electrolytic technologies including electro-splitting of …


On The Molecular Mechanism Of Electron Transfer Of Cytochrome C Modulated By Gold Nanoparticles In Nano-Sandwich Architecture, Shou-Rui Lin, Li-Xu Wang, Xiu-E Jiang, Li-Ping Guo Jun 2012

On The Molecular Mechanism Of Electron Transfer Of Cytochrome C Modulated By Gold Nanoparticles In Nano-Sandwich Architecture, Shou-Rui Lin, Li-Xu Wang, Xiu-E Jiang, Li-Ping Guo

Journal of Electrochemistry

The effects of adsorbed gold nanoparticles on the surface-enhanced infrared absorption (SEIRA) difference spectra of redox-induced cytochrome (Cyt) c in AuNPs/Cyt c/Au sandwich architecture were monitored by SEIRA spectroscopy. The results indicated that the intensity of SEIRA difference spectrum for the vibration of the heme was significantly increased due to the adsorption of gold nanoparticles on the Cyt c. This was induced by the electron transfer between the heme and the gold nanoparticles, which also promoted electron transfer of adsorbed protein. This study suggested a new technique for optimizing the electrochemical property of adsorbed protein.


Synthetic Approaches To Organometallic Complexes For Electronics Applications, Ilya V. Vinogradov Jun 2012

Synthetic Approaches To Organometallic Complexes For Electronics Applications, Ilya V. Vinogradov

Kaleidoscope

No abstract provided.


Electrochemical Study Of Protein Modification, Jing Zhao, Xiao-Li Zhu, Gen-Xi Li Apr 2012

Electrochemical Study Of Protein Modification, Jing Zhao, Xiao-Li Zhu, Gen-Xi Li

Journal of Electrochemistry

Protein post-translational modification is a key physiological procedure, which has received more and more research interests from the scientists not only in protein science but also in some other fields. The usually employed techniques for the study of protein modification include mass spectrum, affinity chromatography, etc. Considering the complexity of protein modification and the urgent demand of such kind of study, it is highly required to develop new techniques to perform more studies. Electrochemical methods, which have been widely used in chemical study and analysis, are playing an increasingly important role in many fields of biological studies. The modification of …


Electrochemical Behavior Of Imidacloprid, Jie-Qiong Wang, Wang Zhang, Ming Chen, Guo-Wang Diao Feb 2012

Electrochemical Behavior Of Imidacloprid, Jie-Qiong Wang, Wang Zhang, Ming Chen, Guo-Wang Diao

Journal of Electrochemistry

The electrochemical behavior of imidacloprid(IDP)on glassy carbon electrode has been investigated by cyclic voltammetry. The result shows that the electrochemical reduction of IDP is irreversible and controlled by diffusion. At 25 ℃, the numbers of the electrons transferred of IDP in the electrochemical reaction are four. The diffusion coefficient of IDP is 2.44×10?6 cm2?s?1 and the diffusion activation energy is calculated to be 9.33 kJ?mol-1.


Determination Of Lidocaine Based On Electrocatalysis Of A Chemically Modified Electrode, Gamze Tan, Gülçi̇n Bolat, Mehmet Ali̇ Onur, Serdar Abaci Jan 2012

Determination Of Lidocaine Based On Electrocatalysis Of A Chemically Modified Electrode, Gamze Tan, Gülçi̇n Bolat, Mehmet Ali̇ Onur, Serdar Abaci

Turkish Journal of Chemistry

The potential application of biochemically modified electrodes was investigated for construction of a drug biosensor. The electrocatalytic response of lidocaine was examined through modified electrodes using the electron transfer ability of hemoglobin (Hb) immobilized on gold film modified with a self-assembled monolayer (SAM) of 3-mercaptopropionic acid (MPA). According to the results of voltammetric studies, Au/MPA/Hb electrodes exhibited high sensitivity and good electrocatalytic activity for the reduction of lidocaine, motivating us to construct drug biosensors. With this study, a new electroanalytical procedure is proposed for the determination of lidocaine level in medical applications or therapeutic formulations containing lidocaine as the active …


Electrochemical Deposition Of Zinc Oxide Crystal Whiskers, Peng-Zeng Lu, Su Li, Jin-Qian Jia, Zhen-Hai Liang Feb 2011

Electrochemical Deposition Of Zinc Oxide Crystal Whiskers, Peng-Zeng Lu, Su Li, Jin-Qian Jia, Zhen-Hai Liang

Journal of Electrochemistry

Pine needle ZnO crystal whiskers were electrodeposited by anodization of zinc foil.The crystal whiskers were characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD) spectroscopy.The results show that the lengths and diameters of ZnO crystal whiskers are 200~300 nm and 20~50 nm,respectively,with the ratio of the length to diameter ranging from 10~15.The whiskers belong to wurtzite ZnO(JCPDS 36-1451) with good crystallinity and high purity.The crystalization behavior of ZnO was studied by cyclic voltammetry.The effects of the surface oxide layer at the zinc substrates and the [Zn(OH)4]2-concentration of the aqueous electrolyte on the formation of zinc oxide whiskers were investigated.


Electrochemical Performance Of Zinc Tetra (Trifluoroethoxy) Phthalocyaninate In Aqueous And Nonaqueous Solvents, Xiao-Shan Wu, Li-Ying Huang, Jin-Que Zhang, Shan-Lan Zhu Nov 2010

Electrochemical Performance Of Zinc Tetra (Trifluoroethoxy) Phthalocyaninate In Aqueous And Nonaqueous Solvents, Xiao-Shan Wu, Li-Ying Huang, Jin-Que Zhang, Shan-Lan Zhu

Journal of Electrochemistry

The cyclic voltammetric performance of ZnPcF in N,N-dimethylformaide(DMF),dimethyl sulfoxide(DMSO) solution and phosphate buffer solutions(PBS) has been examined.The results showed that four pairs of redox peaks appeared in nonaqueous solvents,and the values of half-wave redox potential were 0.558 V,-0.761 V,-1.034 V,-1.417 V,respectively,exhibiting four quasi-reversible phthalocyanine ligand based one-electron transfers.In PBS only two redox peaks were observed and the values of half-wave redox potential were-0.885 V,-1.104 V,exhibiting irreversible behavior characteristics.Comparing to the zinc phthalocyanine(unsubstitute ZnPc),introducing electron-withdrawing groups-trifluoroethoxyl to the peripheral sites of the phthalocyanines shifts the redox processes of the complex toward positive potentials.


In-Situ Surface Enhanced Raman Scattering Electrochemical Investigation Of 4-Aminoantipyrine On Silver Electrode, Li-Jun Zhang, Wei Song, Ling Chen, Zong-Rang Zhang, Hai-Feng Yang Aug 2010

In-Situ Surface Enhanced Raman Scattering Electrochemical Investigation Of 4-Aminoantipyrine On Silver Electrode, Li-Jun Zhang, Wei Song, Ling Chen, Zong-Rang Zhang, Hai-Feng Yang

Journal of Electrochemistry

In this paper,4-AAP was self-assembled on silver surface to form monolayers. Surface-enhanced Raman Spectroscopy ( SERS) was used to in-situ investigate the adsorption mechanism of the 4-aminoantipyrine( 4-AAP) on silver surface dependent on shifting potentials and the effect of solution pH. Based on density functional theory( DFT) calculation of vibration modes,approximate assignment of 4-AAP SERS spectrum was conducted. In situ SERS spectral electrochemical experiments indicated that the 4-AAP monolayers experience a dynamic adsorption process from a tilted fashion to a more vertical mode for benzene ring and more parallel for pyrine ring with the potential applied toward more negative voltages. …


Electrochemical Surface-Enhanced Raman Spectroscopy—Current Status And Perspective, Bin Ren, Jian-Feng Li, Yi-Fan Huang, Zhi-Cong Zeng, Zhong-Qun Tian Aug 2010

Electrochemical Surface-Enhanced Raman Spectroscopy—Current Status And Perspective, Bin Ren, Jian-Feng Li, Yi-Fan Huang, Zhi-Cong Zeng, Zhong-Qun Tian

Journal of Electrochemistry

Electrochemical interface is a very important interface closely related to various energy and life processes. Surface-enhanced Raman scattering was widely used in electrochemistry soon after its discovery to understand the surface bonding,configuration,and orientation of the surface species. In recent 10 years,the fast development of nanoscience and nanotechnology has offered SERS with abundant substrates and characterization methods,which has allowed impressive development of electrochemical SERS. This articles will follow the time line to make systematically overview of SERS on Au and Ag,thin-layer transition-metal SERS,pure transition metal SERS,core-shell SERS and those methods for studying single crystal surfaces,including gap-mode SERS, TERS and SHINERS. Emphasis …


Fabrication Of Electrochemically Activated Glassy Carbon/Bismuth Film Electrodes For Sensitive Analysis Of Pb~(2+) And Cd~(2+), Kang Shi, Wen-Jing Wang, Kun Hu May 2010

Fabrication Of Electrochemically Activated Glassy Carbon/Bismuth Film Electrodes For Sensitive Analysis Of Pb~(2+) And Cd~(2+), Kang Shi, Wen-Jing Wang, Kun Hu

Journal of Electrochemistry

The application of electrochemically activated glassy carbon ( GC) in the in-situ preparing of bismuth film electrodes ( BiFEs) to analyze Pb2 + and Cd2 + was investigated. The glassy carbon electrodes were electrochemically activated by either potentiostic or cyclic polarization in 1 mol·L-1 NaOH solution. Experimental results show that employment of HCl solution as the analytical solution not only can reproducibly renew the electrochemically activated GC electrode surface with an electrochemical clear procedure,but also can greatly enhance the sensitivity of BiFes method for analysis of Pb2 + and Cd2 + . The test range thus was extended to the …


A New Dinuclear Lead(Ii) Complex Of 2,3-Diphenyl-Tetrazole-5-Thione: Synthesis And Characterization, Ruirui Zhuang, Fangfang Jian, Kefei Wang Jan 2010

A New Dinuclear Lead(Ii) Complex Of 2,3-Diphenyl-Tetrazole-5-Thione: Synthesis And Characterization, Ruirui Zhuang, Fangfang Jian, Kefei Wang

Turkish Journal of Chemistry

The present work reports on the synthesis, crystal structure, fluorescence, electrochemical behavior, and thermogravimetric analysis of a new dinuclear lead(II) complex of 2,3-diphenyl-tetrazole-5-thione. Its structure was characterized by X-ray crystallography, IR spectroscopy, and elemental analysis. Each lead atom adopts a distorted octahedral geometry by coordinating to 2 sulfur atoms from 2 2,3-diphenyl-tetrazole-5-thione ligands and 4 oxygen atoms from 3 nitrates. The fluorescence spectrum shows that the title complex has 2 fluorescence emission peaks, at 412 nm and 433 nm. Cyclic voltammetry studies show that the title complex has only one reduction peak, at 0.309 V. The thermogravimetric analysis indicates that …


Electrochemical Characteristics Of Vitaminb_6 At Polybromocresol Green Modified Electrode, Jun Yao, Jiang-Yuan Li, Yang Luo May 2009

Electrochemical Characteristics Of Vitaminb_6 At Polybromocresol Green Modified Electrode, Jun Yao, Jiang-Yuan Li, Yang Luo

Journal of Electrochemistry

Electrochemical characteristics of VB6 were investigated at PBG modified electrode by Cyclic voltammetry and linear sweep voltammetry.The VB6 produced an irreversible oxidation peak at 0.978 V(Vs.SCE) in HAc-NaAc(pH=4.0) buffer solution over the potential range of 0.7 to 1.2 V.The electron number,the proton number,the transfer coefficient were determined to be 1,1 and 0.37,respectively.The oxidation peak currents of VB6 versus its concentration showed a linear relationship in the concentration range of 1×10-3~2×10-5mol/L with the correlation coefficient of 0.9967 and the detection limit of 2×10-6mol/L.The recovery was 100.06%.


The Endpoint Determination In Hydrochloric Pickling By Electrochemistry Method, Shu-Jie Chen, Chun-Jie Ye, Hong-Liang Pan Aug 2008

The Endpoint Determination In Hydrochloric Pickling By Electrochemistry Method, Shu-Jie Chen, Chun-Jie Ye, Hong-Liang Pan

Journal of Electrochemistry

Pickling is an effective way to remove the oxide scale covered on steel materials.It is vital to determine the endpoint in the course of pickling process investigation.According to the reaction process of the oxide scale covered on hot-rolling strips with the hydrochloric acid,a method for determining the endpoint of pickling based on electrochemical principle was suggested.In the pickling experimentation of hot-rolling strips,an accurate precision can be obtained using this method.


Performance Of Magnetic Field Coupled With Electrochemical Process For Preparing Polyaluminum Chloride, Ke-Wu Pi, Wen-Qi Gong, Zheng-Qing Huang Aug 2008

Performance Of Magnetic Field Coupled With Electrochemical Process For Preparing Polyaluminum Chloride, Ke-Wu Pi, Wen-Qi Gong, Zheng-Qing Huang

Journal of Electrochemistry

Polyaluminum chloride(PAC) was prepared by electrochemical process coupled with magnetic field paralleling to the gravitation direction.The electrolyte of 0.1 M AlCl3 solution was used,with the iron plates as cathode and aluminum sheets as anode.PAC of 0.6 M total aluminum(AlT),83.2% Alb to AlT and basicity(Ba)=2.4 was synthesized when magnetic flux density was 0.4T,the distance of electrodes was 15 mm,the voltage of electrolysis cell was 2.4 V and current density was 300 A/m2.Under above experimental conditions,the voltage efficiency,energy efficiency and electrodes surface area to reduction cells of electrochemical reactor were 85.2%,81.5% and 140.1m2/m3,respectively.The polarization curves determined by constant-current method showed that the …


Preparation Of Zn-Ni Alloy Whisker By Electrochemical Method, Zhen-Hai Liang, Xi-Hua Xia May 2008

Preparation Of Zn-Ni Alloy Whisker By Electrochemical Method, Zhen-Hai Liang, Xi-Hua Xia

Journal of Electrochemistry

The Zn-Ni alloy whiskers were prepared by electrochemical method and were characterized by XRD、SEM and EDS methods.The results showed that Ni5Zn21 and Ni3Zn22 whiskers were obtained with the length of 2~4 μm and the diameter of 250 nm,thereby the rations of length/diameter fell between 8 and 16.The electrochemical behavior was investigated by cyclic voltammetry method simultaneously.A new method was provided on whisker preparation based on this work.


Investigation On The Electrochemical And Spectra Properties Of Myricetin, Dong-Mei Wu, Shuang Liu, Hong-Fu Gao, Jin-Lian Li, Hai-Yan Liu, Qi-Chao Liang Aug 2007

Investigation On The Electrochemical And Spectra Properties Of Myricetin, Dong-Mei Wu, Shuang Liu, Hong-Fu Gao, Jin-Lian Li, Hai-Yan Liu, Qi-Chao Liang

Journal of Electrochemistry

The electrochemical mechanism of redox and stability of myricetin were investigated using cyclic voltammetry and electronic absorption spectra.Two oxidation reactions and two reduction reactions were achieved in B-R buffer solution.The oxidation reactions were both due to oxidation of 4′-OH on ring B and 3-OH on ring C within a one electron one proton process.The reduction reactions both correspond to the transformation of 4-carbonyl group on ring C to intermediate radical,and intermediate radical to hydroxyl group within a one electron one proton process,respectively.The redox of myricetin is pH dependent because of deprotonation,resulting in an increase of the antioxidant ability upon formation …


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.


Study On The Electrochemical Extraction Of Oxygen And Influence Factors Of Oxygen Purity, Xiao-Ke Zhi, Guang-Chuan Liang, Xiu-Qin Ou, Shu-Guang Liu, Bin Han May 2007

Study On The Electrochemical Extraction Of Oxygen And Influence Factors Of Oxygen Purity, Xiao-Ke Zhi, Guang-Chuan Liang, Xiu-Qin Ou, Shu-Guang Liu, Bin Han

Journal of Electrochemistry

A method for the electrochemical extraction of oxygen is prasented.The concentration of HO2-ions and the purity of oxygen were measured by KMnO4 standard method,and by cuprammonium absorb method respectively.Effect of the membrane and the spacing between cathode and anode on the purity of oxygen were also tested.The experiment results were showed that the system could work continuously above 500h and the purity of oxygen was above 99.8% when using proper membrane at 80 mA·cm-2 current density,Electrochemical reaction included 4e reacting course and 2e reacting course,the ratio of 2e reaction is about 38%~44% of the whole reaction.


An Electrochemical Dna Biosensor For The Detection Of Dna Damage Caused By Radioactive Iodine And Technetium, Pinar Kara, Kağan Dağdevi̇ren, Mehmet Özsöz Jan 2007

An Electrochemical Dna Biosensor For The Detection Of Dna Damage Caused By Radioactive Iodine And Technetium, Pinar Kara, Kağan Dağdevi̇ren, Mehmet Özsöz

Turkish Journal of Chemistry

A DNA damage process by radioactive iodine (I-131) and technetium (Tc-99m) is described. The procedure relies on a label-free electrochemical DNA biosensor. Fish sperm double stranded DNA was immobilized onto a carbon paste electrode (CPE) by electro deposition and the changes to the guanine oxidation signal were observed upon exposure to radioactive I-131 and Tc-99m by differential pulse voltammetry (DPV). The changes to the signal of guanine after exposure to therapeutic doses of Tc-99m and I-131 showed conformational changes in DNA molecules.


Preparation And Electrochemical Characterization Of Anatase Tio_2 Nanotubes, Bin Cao, Jin-Wei Xu, Ling-Hong Ding, Wei-Feng Zhang Nov 2006

Preparation And Electrochemical Characterization Of Anatase Tio_2 Nanotubes, Bin Cao, Jin-Wei Xu, Ling-Hong Ding, Wei-Feng Zhang

Journal of Electrochemistry

Titanium oxide nanotubes were prepared by hydrothermal treatment of anatase-type TiO_(2) powders and NaOH solution in an autoclave.Transmission Electron Microscopy and X-ray Diffraction showed that the product is anatase-type TiO_(2) nanotubes.The constant charge-discharge current and cyclic voltammetry exhibited the TiO_(2) nanotubes have a large initial lithium insertion capacity of 260 mA·h/g and good reversibility.This study indicates that TiO_(2) nanotubes might be a good negative electrode materical for second lithium battery in the future.


Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang May 2006

Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

Nano materials and nano technology receive great attention all over the world.While electrochemistry has already achieved a great application in industry and it has proved that electrochemistry will play an important role in the field,such as energy source,new materials,life sciences,information sciences,environment and nano sciences.In this paper,the recent developments of electrochemical techniques for the preparing nano materials,application of nano materials in the areas of electrodeposition,batteries,electrocatalysis,sensors are introduced in brief.


Effect Of Applied Potentials On The Formation Of Self-Assembled Monolayers Of Alkanethiol, Diao Peng Feb 2006

Effect Of Applied Potentials On The Formation Of Self-Assembled Monolayers Of Alkanethiol, Diao Peng

Journal of Electrochemistry

The self-assembled monolayers(SAMs)of n-dodecanethiol were prepared on gold substrates under electrochemical conditions using potential step technique.Electrochemical impedance spectroscopy was employed to characterize the SAMs prepared under different substrate potentials.It is found that the potential applied to gold substrate has great influence on the formation of SAMs.Within potential regime-0.8 V to 1.2 V,the increase of applied potential firstly leads to the formation of SAMs with higher packing density,better ordering and less defects.However,after reaching the maximum at 0.4 V,the packing density and the ordering of SAMs begin to deteriorate when the substrate potential is further increased.This work provides solid experimental basis for …


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.


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.


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.