Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 47 of 47

Full-Text Articles in Physical Sciences and Mathematics

In Situ Studies Of Copper Electrodepostion On Hopg By Using Ecstm, Zhaoxiong Xie, Bingwei Mao, Xiangdong Zhuo, Jiqian Mu, Zhaowu Tian May 1996

In Situ Studies Of Copper Electrodepostion On Hopg By Using Ecstm, Zhaoxiong Xie, Bingwei Mao, Xiangdong Zhuo, Jiqian Mu, Zhaowu Tian

Journal of Electrochemistry

In this paper, copper electrodepostion on HOPG had been in situ studied by using a homebuilt electrochemical scanning tunneling microscopy (ECSTM). Three dimensional nucleation and subsequent growth of copper crystals were found as the initial stage of copper deposition on HOPG. In the case of lower overpotential or lower concentration of Cu 2+ , the bulk deposited copper layer tended to form smooth terraces, and grow at the edge of steps. The terraces were stable to some extent, which made it possible to be observed with atomic resolution. At a higher overpotential, the crystal size of copper were somehow smaller. …


Studies Of Surface Treatment Methods And Their Operating Mechanisms For Activation Of Hydrogen Storage Electrode, Ronghui Hu, Hanxi Yang, Shigang Lu, Shengxian Li, Jingcheng Liu, Chongzhi Yang May 1996

Studies Of Surface Treatment Methods And Their Operating Mechanisms For Activation Of Hydrogen Storage Electrode, Ronghui Hu, Hanxi Yang, Shigang Lu, Shengxian Li, Jingcheng Liu, Chongzhi Yang

Journal of Electrochemistry

Surface treatment methods by use of charge discharge cycling, KBH 4 reduction and KOH etching were parallely investigated for the rapid activation of Mn(NiCoMnAl) 5 electrode. It is found that the MH electrode treated with hot and concentrated KOH solution exhibits rapid and full activation, and also gives lower discharge overvoltage, higher stable capacity and improved cycleability. It is also revealed from SEM, EDAX and ICP analysis that the KOH activation of the electrode proceeds mainly through the enrichment of mischmetal and nickel in surface to form electrocatalytically active surface for hydrogen absorption reaction, but the surface modification with KBH …


Study On Electrode Constructure And Electrical Performance Of Na/S Cell, Jianhua Yang, Jiadi Cao May 1996

Study On Electrode Constructure And Electrical Performance Of Na/S Cell, Jianhua Yang, Jiadi Cao

Journal of Electrochemistry

A sodium wick for sodium electrode and trough shaped performs for sulfur electrode in Na/S cell were designed and investigated. The experiments suggested that the sodium wick for sodium electrode not only improved the discharge performance of cell but also reduced the quantity of sodium utilization, and increased the specific energy of Na/S cell. The trough shaped preform with alumina fibres for sulfur electrode decreased the polarization, improved the charge acceptance and prolonged the life of cell.


A Study Of The Electroplated Fe Cr Ni Alloy Microstructure, Donglin Li, Jianping Liu, Fangzhou Guo, Jianrong Hua May 1996

A Study Of The Electroplated Fe Cr Ni Alloy Microstructure, Donglin Li, Jianping Liu, Fangzhou Guo, Jianrong Hua

Journal of Electrochemistry

The microstructure of the electroplated Fe Cr Ni alloys from the mixed carboxylic acid solution containing Cr(Ⅲ) and additives were determined with XRD and SEM. Experimental results showed that, under the experimental condition, the phase component、structure of Cu base electroplated Fe Cr Ni alloys had a critical thickness, which was 11 μm and a critical Ni content, which was 32%. Organic additives, formic acid or polyethylene Glycol, mainly affected the surface、cross section morphology of the electroplated Fe Cr Ni alloys. Adding Mo to the electroplated Fe Cr Ni alloys led to remarkable corrosion resistance in concentrated HCl.


Preparation Techique Of Foamed Nickel By Electrodeposition, Xihua He, Ronghui Hu, Hanxi Yang, Zhengzhong Zuo Feb 1996

Preparation Techique Of Foamed Nickel By Electrodeposition, Xihua He, Ronghui Hu, Hanxi Yang, Zhengzhong Zuo

Journal of Electrochemistry

This paper describes the preparation technique and operation conditions for manufacturing foamed nickel by chemilcal pretreament, electrodeposition and heat treatment. The foamed nickel made in this method showed high porosity, uniformity and considerable strength and tenacity,applicable for various secondary battery electrodes.


The Inhibition Of Amphipathic S- And N-Containing Compounds On Carbon Steel Corrosion, Wei Xing, Yibin Shan, Du Guo, Tianhog Lu, Shiquan Xi Feb 1996

The Inhibition Of Amphipathic S- And N-Containing Compounds On Carbon Steel Corrosion, Wei Xing, Yibin Shan, Du Guo, Tianhog Lu, Shiquan Xi

Journal of Electrochemistry

Ordered monolayers of S- and N-containing amphipathic corrosion inhibitors were depoitod onto the surfaces of carbon steel electrode with super-molecular assembly technique. The effect of molecular aggregation of monolayers on carbon steel corrosion in 0. 05 mol dl ̄(-3)H_2SO_4 and the mechanisms of these inhibitors were discussed in details. It was found that the transport of hydrated hydrogen ion to the surface of steel depends strongly on the inhibitor molecular aggregation in the monolayers.


The Influence Of Cathode Ingredients In Zinc Chloride Type Battery On The Discharge Ability, Shen Qi, Zhuang Biao Feb 1996

The Influence Of Cathode Ingredients In Zinc Chloride Type Battery On The Discharge Ability, Shen Qi, Zhuang Biao

Journal of Electrochemistry

The influence of cathodic powder ingredients in ZnCl_2 type heavy duty battery on the discharge ability has been studied, a suitable battery ingredients is founds.


The Electrochemical Behavior Of C ̄(60)-Chemically Modified Poly(N-Vinylcarhzole)In 1 Mol/L Liclo_4-Thf Solutions, Yu Chen, Zuen Huang, Ruifang Cai, Fupin Zhang Feb 1996

The Electrochemical Behavior Of C ̄(60)-Chemically Modified Poly(N-Vinylcarhzole)In 1 Mol/L Liclo_4-Thf Solutions, Yu Chen, Zuen Huang, Ruifang Cai, Fupin Zhang

Journal of Electrochemistry

The electrochemical behavior of C ̄(60)-PNVC copolymer in 1 mol/L LiClO_4-THF solutions has been studied by cyclic voltammetry.The results demonstrated that there are considerable differences of electronic structure between PNVC (Poly (N-vinylcarbazole )) and C ̄(60)-PNVC copolymer, this being consistent with the ESR results and the oxidstion-reduction activarion of pure PNVC by C ̄(60)-chemical modification. In the potential region,1.3V~-3.5V,five steps,0. 90V/0.60V,0.20V/0.00V,-1.05V/-1.30 V,-1.25V/-1.75 V,-2.00V/-2.50V, of oxidation/reduction proceases were indicated in the cyclic voltammetry for pure PNVC,whereas seven steps,0.20V/0.20V,-0.30V/-0.50 V,-0. 60V/-0.60 V,-0.80V/-1. 10 V,-1.95V/-2. 10 V,-2. 50 V/-2. 70 V,-3. 00V/-3. 00 V, of oxidation/reduction processes for the C ̄(60)-PNVC copolymer were observed under the idenrical …


Electrochemical Studies On Corroding Metallic Electrodes In Frequency Domain, Chu' Nan Cao Feb 1996

Electrochemical Studies On Corroding Metallic Electrodes In Frequency Domain, Chu' Nan Cao

Journal of Electrochemistry

The electrochemical studies on corroding metallic electrodes carried out in the State Key Laberatory for Corrosion and Protection are reviewed briefly: (1) General equations of faradaic admittance under potential-control condition were derived based on the stabillity conditions of steady processes. The faradaic admittance at mixed potential then was deduced based on these equations and the electrochemical impedance spectroscopy (EIS) at corrosion potentials in the solutions containing interface inhibitors was diseussed by application of the thecetical results obtained. (2) The spectral power density (SPD) curves for electrochemical noise (EN) during the initial stagu of pitting corrosion were observed for iron and …


An Indirect Electrochemical Oxidation Of Toluene─Catalytic Effects Of Ag(Ⅰ) On Mn(Ⅱ)/Mn(Ⅲ) Couple Transition At Pt Electrode, Zhonghua Wang, Yunan Qu, Xingguo Yan, Qngmin Hua, Guacai Chen, Zhongquan Wang Feb 1996

An Indirect Electrochemical Oxidation Of Toluene─Catalytic Effects Of Ag(Ⅰ) On Mn(Ⅱ)/Mn(Ⅲ) Couple Transition At Pt Electrode, Zhonghua Wang, Yunan Qu, Xingguo Yan, Qngmin Hua, Guacai Chen, Zhongquan Wang

Journal of Electrochemistry

The Catalytic effects of Ag(Ⅰ) on toluene oxidation by Mn(Ⅲ) as well as the anodic generation of Mn(Ⅲ) were investigated. The rates of toluene oxidation were first order with respect to both Ag(Ⅰ) and Mn(Ⅲ). Ag(Ⅱ) formed on the surface of the platinum anode when Ag(Ⅰ) was present in the anolyte, which catalyic the Mn(Ⅱ) to Mn(Ⅲ) in solution.


Ftis Observation Of Twin Adsorbates Of Co On Rh Electrode In Acid Solution, Wenfeng Lin, Shigang Sun Feb 1996

Ftis Observation Of Twin Adsorbates Of Co On Rh Electrode In Acid Solution, Wenfeng Lin, Shigang Sun

Journal of Electrochemistry

Because of its great importance both in electrocatalysis and C1 chemistry applications, the adsorption of CO on metallic electrodes such as Pt, Pd, Au, Ag, RhF ̄[1~2], etc. has been extensively studied by in situ infrared spectroscopy Since 1981. In all these studies only three types of CO adsorbates, i. e. , linear (2 090~2 000 cm ̄(-1)), bridgrd (2 000~1 900 cm ̄(-1)) or multi-bonded (1900~1 800 cm ̄(-1)) species, were identified. A different absorbate, twin CO on rhodium ((Rh (CO)2) , does exist on the solid/gas interface of highly dispersed Rh or Rhn clusters[3~4] on supports,this species originating a doublet at 2100 …


Determination Of Transport Number Of The Modified Liclo_4- (Peo)_(20) Polymer Electrolyte, Ruqi Zhou, Qngguo Liu, Weihua Qiu, Yun Zhang, Yuee Zhao Feb 1996

Determination Of Transport Number Of The Modified Liclo_4- (Peo)_(20) Polymer Electrolyte, Ruqi Zhou, Qngguo Liu, Weihua Qiu, Yun Zhang, Yuee Zhao

Journal of Electrochemistry

In this work a combination method of A. C. Impedance and chronoamperometry was used to determine the lithium ion transport number of LiClO_4·(PEO)_(20)·(PC)_(12)·(EC)_(12) polymer electrolyte. It is known that lithium is thermodynamically unstable in non-aqueous or polymer electrolytes, leading to the formtion of a film on lithium surface, called as solid electrolyte interphase (SEI). The presence of SEI layer will greatly influence the experimental result of lithium ion transport number. The new method avoid the effect of SEI layer, and can give correct transport number of lithium ion in the electrolyte of DCIO_4·(PED)_(20)·(PC)_(12)·(EC)_(12). The exporimental result indicates that the conducrivity …


Hydrogen Evolution Reaction On Nanocrystalline Co-Mo/Ni Composite-Coated Electrodes, Weizeng Yu, Jie Ma, Yiming Chu, Huizhe Zhu, Hongjie Wang, Shuncheng Liu Feb 1996

Hydrogen Evolution Reaction On Nanocrystalline Co-Mo/Ni Composite-Coated Electrodes, Weizeng Yu, Jie Ma, Yiming Chu, Huizhe Zhu, Hongjie Wang, Shuncheng Liu

Journal of Electrochemistry

The electrochemical behaviours of the hydrogen evolution reaction(HER) at electrodes prepared by composite coating of nanocrytstalline Co-Mo alloy particles formed by ball milling on nickel base has been sludied by using sleady-state polarization and ac impedance techiu ques.The microstructure and the size of the nanocrystals of Co- Mo alloy and the morphology of the composite-coating surface of the electrodes are measured by XRD, TEM and SEM. Results show that the nanocrystalline Co-Mo alloys prepared by high energy ball milling has high electrocatalytic activity for HER. The electrocatalytic activity for the HER is enhanced and the energy of activation for HER …


Electrochemical Ploymerization Of Aniline In The Alkaline Solution And Properties Of Polymer, Shaolin Mu, Jinqing Kan, Aiguang Zhang Feb 1996

Electrochemical Ploymerization Of Aniline In The Alkaline Solution And Properties Of Polymer, Shaolin Mu, Jinqing Kan, Aiguang Zhang

Journal of Electrochemistry

A deep yellow polyaniline was formed at the anodic electrode during electrochemical oxidation of aniline in the alkaline solution.The peak of oxidation potential for aniline in the alkaline solution was 0. 7 V (vs.Ag/AgCl with a saturated KCl solution),which is about 0. 3V less than that in the acidic solution.The results from rotating ring-disk electrode experiment show that two soluble intermediates were generated during electrochemical oxidation of aniline.The colour of the polymer in the alkaline solution is independent of applied potential and pH values.An adsorption peak was observed in the UV region at 500 nm for the polymer.The polymer has …


Development Of The High Capacity Sintered Type Nickel Positive Electrode, Guohua Yu, Shijie Zhang, Xiaolin Wang, Jingqi Wei Feb 1996

Development Of The High Capacity Sintered Type Nickel Positive Electrode, Guohua Yu, Shijie Zhang, Xiaolin Wang, Jingqi Wei

Journal of Electrochemistry

By improving the design and technologies of the sintered type nickel oxide positive electrode for the NiMH batteries, We do our best to increase the sinter volume and porosity,the amount of the active materals and their utilization, so we have fabricated the high capacity sintered typo nickel electrodes fitting for the NiMH battreies. The sfecitic capacity of the lot produced electrodes is up to 550 mA/cm ̄3.


Research On Molten Carbnate Fuel Cell, Naichao Li, Baolian Yi, Lianying Kong, Enjun Zhang, Huaxin Lin, Tianxi Qu, Yingcai Cheng Feb 1996

Research On Molten Carbnate Fuel Cell, Naichao Li, Baolian Yi, Lianying Kong, Enjun Zhang, Huaxin Lin, Tianxi Qu, Yingcai Cheng

Journal of Electrochemistry

Cold-roll-milling has been evaluated as a technique for preparing porous LiAlO_2 matrices for use as a molten carbonate fuel cell electrolyte matrix. This technique produces reliable electrolyte structures with the following characteristics and advantages: ease of handling, uniform thickness, using nontoxic inorganic solvents, controlled pore size distribution, and ability to be impregnated with the alkali carbonate without fracrure.The Molren Carbnatod Fuel Cell(MCFC) was assembled from sintered Ni electrodes and LiAlO_2 electrolyte matrix, the electrode area is 28 cm ̄2, the effect of operating conditions on cell performance was tested, it was found that the cell performance changed little with many times …


Study On The Manufacture Of Pt/C Gas-Diffusion Electrodes, Yonglin Ma Feb 1996

Study On The Manufacture Of Pt/C Gas-Diffusion Electrodes, Yonglin Ma

Journal of Electrochemistry

The various methods of manufacturing gas-diffusion electrodes are reviewed and a new method of preparing the Pt/C electrocatalyst and the gas-diffusion electrodes is explored in this paper. The electrochemical performance of resulting electrodes in concentrated phosphoric acid for oxygen reduction at 150℃ are compared with the commercial electrode which purched from Giner Inc. (U. S. A). The results show that the performance of the Pt/C electrodes which manufactured by the method in this paper has been greatly improved. Therefor, a fuel cell using such electrodes has high industrial value.