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1998

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Full-Text Articles in Materials Science and Engineering

Związki Siarki Emitowane Z Procesu Wielkopiecowego, Marian Mazur, Marek Bogacki, Robert Oleniacz Dec 1998

Związki Siarki Emitowane Z Procesu Wielkopiecowego, Marian Mazur, Marek Bogacki, Robert Oleniacz

Robert Oleniacz

The article describes the problem of the presence of sulfur in the blast furnace process and identifies emission sources of sulfur compounds in this process. On the basis of the measurements and calculations, the types and quantities of these compounds emitted to the air were determined. It was found that pig iron smelting in a blast furnace causes emissions of COS, SO2 and H2S. These emissions occur by losses of blast furnace gas (COS and SO2), transport of blast furnace slag inside the furnace hall (SO2) and treatment of the slag by granulation (H2S). However, the most important are only …


An Analysis Of Texture Resulting From Thermomechanical Processing Of Ti-6al-V, David J. Brock Dec 1998

An Analysis Of Texture Resulting From Thermomechanical Processing Of Ti-6al-V, David J. Brock

Masters Theses

An investigation of texture and microstructure formation in Ti-6Al-4V after thermomechanical processing and heat treating was performed. X-ray diffraction was used to measure prismatic and pyramidal pole figures. These pole figures were used to calculate basal pole figures, which showed significant changes in texture from heavy rolling and near or above β-transus heat treatments. Primary texture components were found to be strengthened by near β-transus heat treatments. For heavily rolled material, above β-transus heat treatments were found to reverse the primary texture components order of dominants. Heavy rolling was found to reduce the RD component and strengthen the TD.


Primary Research Of Reversible Proton Exchange Membrane Regenerative Fuel Cells, Zhigang Shao, Baolian Yi, Ming Han Nov 1998

Primary Research Of Reversible Proton Exchange Membrane Regenerative Fuel Cells, Zhigang Shao, Baolian Yi, Ming Han

Journal of Electrochemistry

In this paper, we report the results of our studies on regenerative proton exchange membrane fuel cell(RPEMRFC) catalysts, electrode preparation and their performances. The Pt catalyst for the oxygen electrode was replaced by 60 w%Pt+40 w%IrO 2 which reduces polarization by 0.2 V in a polymer protone exchange membrane fuel cell. The cycle performance of RPEMRFC was found to be manly effected by the stability of the diffiusion layer of bifunctional oxygen electrode.


The Effect Of Suspended Particles On The Corrosion Resistance Of Electrodeposited Zinc Powders, Qingwen Li, Qing Yang, Xi Xia Nov 1998

The Effect Of Suspended Particles On The Corrosion Resistance Of Electrodeposited Zinc Powders, Qingwen Li, Qing Yang, Xi Xia

Journal of Electrochemistry

Zinc powders were electrodeposited from ZnCl 2 baths with containing suspension of unsoluble particles such as graphite, PbO 2,SnO 2,TiO 2, SiO 2 etc.. The structure, morphology and corrosion behavior of zinc powder were analyzed. SEM results showed that the dendritic growth of zinc can be inhibited by applying the suspension method. Suspension of PbO 2, SnO 2, TiO 2, SiO 2 and In 2O 3 could greatly improve the corrosion protection of zinc powder in 5 mol/L KOH. In addition, fractal theory is employed to further explain the results.


Study On Ni Co S Mo Alloys New Cathode Material For Aquous Electrolysis, Yuanshou Xie, Quanfeng Liu Nov 1998

Study On Ni Co S Mo Alloys New Cathode Material For Aquous Electrolysis, Yuanshou Xie, Quanfeng Liu

Journal of Electrochemistry

The parameters of electrodeposion of Ni Co S Mo alloy were studied. The experimental results indicate that the electrodeposition alloy shows high catalytic activity for hydrogen evolution reaction, as well as better mechanical strength and higher chemical stability. The mechanism of catalytic hydrogen evolution reaction on this type of alloy electrode was also investigated by means of polarization curve and cyclic voltametry.


The Latest World Wide Progress In Solid Oxide Fuel Cell, Jiang Yi Nov 1998

The Latest World Wide Progress In Solid Oxide Fuel Cell, Jiang Yi

Journal of Electrochemistry

Solid oxide fuel cell(SOFC) is a novel, green electricity generation technology, which has been showing rapid development since 1980's. In light of its high efficiency, environmental friendly, fuel adaptability and long term stability, the Research, Development and Demonstration(RD&D) of this hype of full cell have been emphasized in a large number of developed countries. Based on the information communicated at the latest symposium on SOFC held last year in Aachen(Germany) and the knowledge gained through years of research in this field, a comprehensive review on the latest development of the tubular, this planar SOFC as well as on a number …


A Preliminary Study Of The Synthesis Of Tin Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Hanxi Yang, Jutang Sun, Xingping Ai Nov 1998

A Preliminary Study Of The Synthesis Of Tin Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Hanxi Yang, Jutang Sun, Xingping Ai

Journal of Electrochemistry

An amorphous lithium inserting anode material based on Tin oxide glass was synthesized by salification in solution and its properties on lithium intercalation was investigated by X ray diffraction(XRD), microelectrode voltammetry and charge discharge measurements. The results have shown that this kind of material has considerable electrochemical reversibility toward lithium intercalation deintercalation. The available discharge capacity of the material reaches 430 mA·h/g with charge_discharge efficiency over 90%, showing a great potential for practical use.


Oxygen Evolution Behavour On Ni Electrode In Koh Solution, Xiaoyan Cao, Huatang Yuan, Zuoxiang Zhang Yunshi Zhou Nov 1998

Oxygen Evolution Behavour On Ni Electrode In Koh Solution, Xiaoyan Cao, Huatang Yuan, Zuoxiang Zhang Yunshi Zhou

Journal of Electrochemistry

The steady_state polarization curves of oxygen evolution were measured at temperatures between 22~70 ℃ on Ni electrode in 30 wt.% KOH solution by galvanostat methode. The exchange current densities, Tafel slopes and transfer coefficients were studied. It was found that 40 ℃ is a special temperature, near which the kinetic parameters change abrupdy. The Tafel slopes for oxygen evolution reactions at higher overpotentials change from more than 120 mV to about 70 mV when the temperature raises to 40~70 ℃ from 22~35 ℃. Simultaneously, the heat of activation is changes from 79.88 kJ/mol to 55.32 kJ/mol. Moreover, the -(η/Τ) i …


Corrosion Characteristics Of Electrodeposited Ni Mo P Alloy Immersed In Nacl Solution, Yue Zeng, Hongxin Huang, Xiaoming Xiao, Shixun Lian Nov 1998

Corrosion Characteristics Of Electrodeposited Ni Mo P Alloy Immersed In Nacl Solution, Yue Zeng, Hongxin Huang, Xiaoming Xiao, Shixun Lian

Journal of Electrochemistry

The corrosion characteristics of electrodeposited Ni Mo P alloy immersed in 5wt.% NaCl solution were investigated using immersion, anodic polarization curves, XPS and AES analysis. The corrosion rates of amorphous Ni Mo P alloys are lower than that of crystalline Ni Mo P alloys. Anodic polarization curve experiments show that for the electrodeposited Ni Mo P alloys, the nickel mol fraction of which has in between 0.719 and 0.868, the corrosion potential moves to positive with the increase of P content, and the peak current value of active region increase with the increase of Mo content in alloys, though the …


The Study On The Performance Of Mcfc Matrix Prepared By Flow Cast, Huaxin Lin, Baolian Yi, Naichao Li, Tianxi Qu, Enjun Zhang, Lianyin Kong, Yingcai Chen Nov 1998

The Study On The Performance Of Mcfc Matrix Prepared By Flow Cast, Huaxin Lin, Baolian Yi, Naichao Li, Tianxi Qu, Enjun Zhang, Lianyin Kong, Yingcai Chen

Journal of Electrochemistry

The matrix for MCFC were prepared by flow cast technique which gives reproducible and reliable results. Its mean pore radius is about 0.18 μm, and the porosity is about 65%. The performance of MCFC stacked with this type of matrix is 0.854 V at 200 mA/cm 2.


The Study Of Poly [N (3 Ferrocene Acetamino Propyl Pyrrole] Film Modified Glucose Electrode, Chengyun Tian, Jing Chen, Li Zhang Nov 1998

The Study Of Poly [N (3 Ferrocene Acetamino Propyl Pyrrole] Film Modified Glucose Electrode, Chengyun Tian, Jing Chen, Li Zhang

Journal of Electrochemistry

A poly [N (3 ferrocene acetamino propyl pyrrole)]film modified electrode was fabricated and studied by cyclic voltammetric method. The result shows that the modified electrode can give stable redox peaks of ferrocene, and an obvious catalytic peak due to glucose; This modified electrode was used to tabricate a glucose sensor which operates at +0.2 V, so that the ascorbic acid or uric acid doesn't affect the accuracy detection of glucose concentration. The sensor has a linear range of 0.1~10 mmol/L glucose, which the period of long term stability and response time of the sensor are about ten days and 2 …


Studies Of Spinal Li 1+X Mn 2-X O 4 Rechargeable Lithium Ion Battery, Xiaomei Wu, Qinghe Yang, Zhongkao Jin, Haoqing Wu, Xiangfu Zong Nov 1998

Studies Of Spinal Li 1+X Mn 2-X O 4 Rechargeable Lithium Ion Battery, Xiaomei Wu, Qinghe Yang, Zhongkao Jin, Haoqing Wu, Xiangfu Zong

Journal of Electrochemistry

The spinel Li intercalation compound Li 1+ x Mn 2- x O 4(0< x <1) was prepared by using techniques of cyclic voltammetry. The electrochemical parameters of Li 1+ x Mn 2- x O 4 electrode vary as either the starting materials or the synthesis temperature changes. It was found that the initial capacity and reversible behaviors of the Li 1+ x Mn 2- x O 4 electrode depends on the amount of the excess Li, represented as x in Li 1+ x Mn 2- x O 4. The reversible of Li intercalation process for Li 1+ x Mn 2- x O 4 electrode was demonstrate by cyclic voltammograms.


Drect Electro_Oxidation Synthesis Of D Arabinose On Spectroscopic Graphite Electrode, Hei Wei, Huang Ying Nov 1998

Drect Electro_Oxidation Synthesis Of D Arabinose On Spectroscopic Graphite Electrode, Hei Wei, Huang Ying

Journal of Electrochemistry

D Arabinose synthesized by direct electro_oxidative decarboxylation of D gluconate on graphite electrode from aqueous solutions. The effects of D gluconate concentration, electrolysis potential, temperature and electrolyte composition on the current efficiency and product yield of electrosynthsis are discussed. The laboratory scale electrosynthesis was achieved with flow through cell.The optimum technology conditions for electrosynthesis were obtained with orthogonal design method.Both galvanostatic and potentionstatic conditions have been exploited, the later was found to be more effective.


Study On Electrosynthesis Of Butyl Butyrate At Conducting Oxide Anode Support On Titanium, Junxiang He, Jincheng Zhou Nov 1998

Study On Electrosynthesis Of Butyl Butyrate At Conducting Oxide Anode Support On Titanium, Junxiang He, Jincheng Zhou

Journal of Electrochemistry

Synthesis of butyl butyrate by direct electroxidation of n butyl alcohol and the electrochemical behaviors of several selected conducting oxide electrodes (Pb/PbO 2、Ti/PbO 2、i/SnO 2 +Sb 2O 3 /PbO 2 and Ti/SnO 2+Sb 2O 3+PdO x/PbO 2) have been investigated. The results demonstrated that the intermediate layers of SnO 2、Sb 2O 3 and PdO x could significantly decrease the interfacial resistance of the electrodes,and that the Ti/SnO 2+Sb 2O 3+PdO x/PbO 2 electrode possessed better electrocatelytic performance than others.


Specific Heat And Transport “Anomalies” In Mixed Alkali Glasses, Peter F. Green, Richard K. Brow, James J. Hudgens Nov 1998

Specific Heat And Transport “Anomalies” In Mixed Alkali Glasses, Peter F. Green, Richard K. Brow, James J. Hudgens

Materials Science and Engineering Faculty Research & Creative Works

We show that changes in the relative mole fractions of Li2O and Na2O in alkali metaphosphate glasses lead to “anomalies” in the specific heat and structural relaxations. The heat capacity change between the liquid and glassy states, Δcp(Tg), at the calorimetric glass transition temperature, Tg, exhibits a minimum when the mole fractions of Li2O and Na2O are comparable. Moreover, systematic changes in the temperature dependence of the viscosity, η, i.e., changes in the “fragility” of the system, accompany these changes in mole fraction. This observed dependence …


Multiscale Modeling Of Recrystallization, A. W. Godfrey, E. A. Holm, D. A. Hughes, M. A. Miodownik, Richard Alan Lesar Nov 1998

Multiscale Modeling Of Recrystallization, A. W. Godfrey, E. A. Holm, D. A. Hughes, M. A. Miodownik, Richard Alan Lesar

Richard Alan Lesar

We propose a multi length scale approach to modeling recrystallization which links a dislocation model, a cell growth model and a macroscopic model. Although this methodology and linking framework will be applied to recrystallization, it is also applicable to other types of phase transformations in bulk and layered materials. Critical processes such as the dislocation structure evolution, nucleation, the evolution of crystal orientations into a preferred texture, and grain size evolution all operate at different length scales. In this paper we focus on incorporating experimental measurements of dislocation substructures, misorientation measurements of dislocation boundaries, and dislocation simulations into a mesoscopic …


Microstructures And Mechanical Properties Of Two-Phase Alloys Based On Nbcr2, Katherine C. Chen, Paul G . Kotula, Carl M. Cady, Michael E. Mauro, Dan J. Thoma Oct 1998

Microstructures And Mechanical Properties Of Two-Phase Alloys Based On Nbcr2, Katherine C. Chen, Paul G . Kotula, Carl M. Cady, Michael E. Mauro, Dan J. Thoma

Materials Engineering

A two-phase, NbCrTi alloy (bcc + C15 Laves phase) has been developed using several alloy design methodologies. In efforts to understand processing-microstructure-property relationships, different processing routes were employed. The resulting microstructures and mechanical properties are discussed and compared. Plasma arc melted (PAM) samples served to establish baseline, as-cast properties. In addition, a novel processing technique, involving decomposition of a supersaturated and metastable precursor phase during hot isostatic pressing (HIP), was used to produce a refined, equilibrium two-phase microstructure. Quasi-static compression tests as a function of temperature were performed on both alloy types. Different deformation mechanisms were encountered based upon temperature …


Synthesis And Characterization Of Silicon Dioxide Films Using Diethyl Silane And Oxygen, Kiran Kumar Aug 1998

Synthesis And Characterization Of Silicon Dioxide Films Using Diethyl Silane And Oxygen, Kiran Kumar

Theses

This study focuses on producing thin and thick silicon dioxide films towards the fabrication of integrated optical sensor capable of monitoring and determining in-situ, the concentration of numerous analyze species simultaneously. In this study, diethylsilane (DES) has been used as a precursor to produce silicon dioxide films by low pressure chemical vapor deposition. The films were synthesized with two different flow ratios of oxygen to DES in the temperature range of 550°C to 800°C at a constant pressure of 200mTorr. The films deposited with lower oxygen to DES flow ratio have very high growth rate but suffer from high tensile …


Electrochemical Behavior Of Chemically Prepared Ring-Substituted Polyanilines, Lizong Dai, Huihuang Wu Aug 1998

Electrochemical Behavior Of Chemically Prepared Ring-Substituted Polyanilines, Lizong Dai, Huihuang Wu

Journal of Electrochemistry

No abstract provided.


Direct Electrochemical Reaction Of Cytochrome C At The Poly (Ethylene Oxide) Film Modified Gold Electrodes, Xiaogang Qu, Gongquan Sun Aug 1998

Direct Electrochemical Reaction Of Cytochrome C At The Poly (Ethylene Oxide) Film Modified Gold Electrodes, Xiaogang Qu, Gongquan Sun

Journal of Electrochemistry

In this paper, the direct electrochemical reaction of cytochrome c was sudied at the poly (ethylene oxide) film modified gold electrodes. It was found the PEO is a good promoter for the electrochemical reaction of cytochrome c, and the reversibility of reaction of cytochrome c was found to depend on the molecular weight of PEO and the morphology of the PEO films.


Modification Of Carbon Anode Materials Of Lithium Ion Secondary Battery, Yuping Wan Chunrong Wu, Changyin Jiang, Jiangiun Li Aug 1998

Modification Of Carbon Anode Materials Of Lithium Ion Secondary Battery, Yuping Wan Chunrong Wu, Changyin Jiang, Jiangiun Li

Journal of Electrochemistry

In this paper, the latest research work on modification of carbon anode materials of lithium ion secondary battery is reviewed. Modification methods include: incorporation of nonmetal elements such as boron, silicon, nitrogen, phosphorus and sulfur, metal elements such as potassium, aluminum, gallium and transitional metal elements such as vanadium, nickel, cobalt, copper and iron and surface treatment such as oxidation and formation of surface layer. Since these methods can affect the carbon materials' electronics state, crystal structure and surface structure, the electrochemical properties of the carbon materials could probably be improved. Besides, mechanisms for lithium storage in carbonaceous materials are …


External Transducing Measurement Of The Internal Pressure In Sealed Battery By Resistance Strain Gauge, Hanxi Yang, Ronghui Hu, Xinping Ai, Congzhi Yang, Shengxian Li Aug 1998

External Transducing Measurement Of The Internal Pressure In Sealed Battery By Resistance Strain Gauge, Hanxi Yang, Ronghui Hu, Xinping Ai, Congzhi Yang, Shengxian Li

Journal of Electrochemistry

A novel method to monitor dynamically the internal pressure of sealed battery with no damage of the battery by using of resistance strain measurement technique is presented. This technique employs the resistence strain gauges in touch of the battery case and to detect the minimal change in the battery deformation due to the increasing internal pressure, electrode expantion or intrenal temperature rise. Application of the technique for the study of the effects of the battery processing factors on the battery performance is described taking Ni MH battery as example.


Lithiun Insertion In Carbon Nanotubes, Guotao Wu, Chunsheng Wang, Zhongfu Qi, Wenzhu Li Aug 1998

Lithiun Insertion In Carbon Nanotubes, Guotao Wu, Chunsheng Wang, Zhongfu Qi, Wenzhu Li

Journal of Electrochemistry

Carbon nanotubes were produced by chemical vapour deposition(CVD) of acetylene under hydrogen gas.The reversible specific capacity of carbon nanotubes is up to 700 mAh/g, much higher than the theoretical specific capacity of graphite(372 mAh/g).After twenty charge/discharge cycles,the discharge capacity of carbon nanotube anode still maintains 65.3% of its original discharge capacity . Besides, the charge/discharge efficiency of carbon nanotube in the first charge/discharge cycle was found to improve from 42.6% up to 55.9% by coating carbon nanotubes with copper.


Electrooxidation Of Benzene To Benzoquinone In A Packed Bed Reactor, Xinsheng Zhang, Ping Ding, Yingchun Dai, Weikang Yuan Aug 1998

Electrooxidation Of Benzene To Benzoquinone In A Packed Bed Reactor, Xinsheng Zhang, Ping Ding, Yingchun Dai, Weikang Yuan

Journal of Electrochemistry

A packed electrode reactor was used to oxidize to benzoquinone. Anode bed of the reactor has a size of 10~30 mm×450 mm×50 mm(thickness×length×width),and was packed porous lead alloy. A dispersion of benzene in 1 mol/L aqueous sulfuric acid was passed through the reactor. Current efficiency for benzoquinone generation is 62.9% at optimal operating condition: velocity of electrolyte flow, 0.19 ms -1 ;current, 10 A; thickness of anode bed, 10 mm, and percentage of benzene, 24%.


Studies On The Electrode Kinetics Of Electrooxidation Of Mn 2+, Wanli Hu, Tong Su, Wei Guo, Ding Zhou Aug 1998

Studies On The Electrode Kinetics Of Electrooxidation Of Mn 2+, Wanli Hu, Tong Su, Wei Guo, Ding Zhou

Journal of Electrochemistry

The mechanism of electrooxidation of MnSO 4 on Pb Sb As alloy anode was investigated by using rotating disc electrode technique. The results shown that the conditional standard potential of Mn(Ⅲ)/Mn(Ⅱ)in 40% H 2SO 4 is 0.886 4 V.The rate controlling step of electrode process is mixed controlled by charge transfer and diffusion.


Studies On The Preparation Of Nanophase Electrode Materials And Its Electrochemical Properties(Ⅲ)—Performance Of Nm Γ Mno 2 Obtained By Microemulsion Method, Liu Ling, Xia Xi Aug 1998

Studies On The Preparation Of Nanophase Electrode Materials And Its Electrochemical Properties(Ⅲ)—Performance Of Nm Γ Mno 2 Obtained By Microemulsion Method, Liu Ling, Xia Xi

Journal of Electrochemistry

A nanophase MnO 2 was synthesized using w/o microemulsion as reation media, The most favorable experiment conditions for the preparation of nm MnO 2 were researched. XRD,TEM,AC impedance, cyclic voltammetry etc. examinations were used to characterize the sample comparison with the classical MnO 2 (I.C.No.1EMD,electrolytic manganese dioxide). Sample shows that the crystal styucture of the synthesized samples are mainly γ MnO 2, with average particle size in the nanometer as shown by TEM. It was found that the discharge capacity of nm MnO 2 obtained is significantly higher than that of the I.C.No.1 EMD.


Study Of Proton Exchange Membrane Fuel Cells(Pemfc), Shanhai Ge, Baolian Yi, Hongfen Xu, Ming Han, Zhigang Shao Aug 1998

Study Of Proton Exchange Membrane Fuel Cells(Pemfc), Shanhai Ge, Baolian Yi, Hongfen Xu, Ming Han, Zhigang Shao

Journal of Electrochemistry

The electrode kinetic parameters for proton exchange membrane fuel cells(PEMFC) were investigated by measuring the relations of cell potential and current density. An experimental stack of PEMFC which can be operated at E cell =0.7V, I =0.55A/cm 2 steadily is presented, and the effects of electrode structure and operation conditions such as temperature, pressure, humidification, flow rate on the performance of PEMFC are discussed.


Formation And Effect Of Tribo Cell For Fe Cr Alloy, Dongbai Sun, Tao Li, Hongying Yu, Deji Yang Aug 1998

Formation And Effect Of Tribo Cell For Fe Cr Alloy, Dongbai Sun, Tao Li, Hongying Yu, Deji Yang

Journal of Electrochemistry

The micro galvanic corrosion of 1Cr18 alloy and its effects on the triboelectrochemical behavior were investigated and analyzed in this article. It is shown that the micro galvanic corroson is due to the electrochemical inhomogenity on the surface of the alloy during the friction process. Like galvanic corrosion,the micro galvanic corrosion behaviors are greatly affected by the area ratio of unrubbed to rubbed surface.The load effects on electrochemical behavior of 1Cr18 alloy are also attributed to existence of electrochemical inhomogenity on the surface of materal.


Ac Impedance Study Of The La 0.8 Sr 0.2 Mno 3/Ysz Electrode, Shizhong Wang, Yi Zhang Yahong Jiang, Jingwang Yan, Wenzhao Li Aug 1998

Ac Impedance Study Of The La 0.8 Sr 0.2 Mno 3/Ysz Electrode, Shizhong Wang, Yi Zhang Yahong Jiang, Jingwang Yan, Wenzhao Li

Journal of Electrochemistry

Electrochemical reaction of oxygen on the La 0.8 Sr 0.2 MnO 3/YSZ electrode has been investigated in detail with AC impedance. The results demonstrated that the rate determining step(rds) of the reaction varies with the temperature, oxygen partial pressure and overpotential applied. At open circuit potential, the rds is the dissociative adsorption of oxygen on the LSM surface. A large number of electron holes are generated at high anodic overpotentials, while oxygen vacancies are formed at high cathodic overpotentials. The formation of the electron holes results in the electronic conduction of the YSZ electrolyte and the extension of the electrochemical …


The Hydrogen Evolution Reaction On The Hydrogen Storage Alloy Electrode, Shigang Lu, Qun Li, Qingguo Liu, Chun Lu, Bing Dang Aug 1998

The Hydrogen Evolution Reaction On The Hydrogen Storage Alloy Electrode, Shigang Lu, Qun Li, Qingguo Liu, Chun Lu, Bing Dang

Journal of Electrochemistry

The hydrogen evolution reaction was studied in 1 mol/L KOH solution on the hydrogen storage alloy Mm(NiCoMnAl) 5 electrode using open circuit potential decay and ac impedance technique. The reaction was found to proceed by the Volmer(discharge)-Tafel(recombination)mechanism. The measured overpotential η can be subdivided into two components η 1 and η 2 corresponding to the elementary Volmer and Tafel reaction. The Faradaic impedance was analyzed and characterized by the Volmer reaction. Then the exchange current density was evaluated . It was founded that the activity of hydrogen storage alloy electrode for the hydrogen evolution reaction was similar to that of …