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Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB_3-type hydrogen storage alloy electrodes

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science china(Technological sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2,WU YaoMing1,MA LiQun2,SHEN XiaoDong2 & WANG LiMin1 1 State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of sciences,C hangchun 130022,china 2 College of material science and engineering,Nanjing University of Technology,Nanjing 210009,china 1. State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The(La0.67Mg0.33)1-xTixNi2.75Co0.25(x = 0,0.05,0.10,0.15 and 0.20,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 1200 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

Texture Analysis of Superconducting Films Based on YBCO System

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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 107-109页

作者： Nan Chen Weimin Mao(material science and engineering School, University of science and Technol0gy Beijing, Beijing 100083 china)(Department of materials science and engineering, University of Petroleum, Beijing 102200, china) material science and engineering School University of Science and Technology Beijing Beijing 100083 China Department of materials science and engineering University of Petroleum Beijing 102200 China

Textures in different layers of superconductors based on YBCO system are analyzed using the methods of pole figure and con-ventional φ scans. It is shown that the φ scanning technology has only 1-dimensional description and could omit some information of3-dimensional orientaion distribution, which will influence the superconductor quality The pole figure method, in contrast, demonstra-tes the orientation distribution 2-dimensionally and gives a comprehensive view of thin filIn textUr, which is a much bettCr method fortexture analysis in superconducting films, in which there is commonly an unique high sharpness textur component.

关键词： superconductor thin film texture YBCO pole figure

Study on BaTiO_3 films prepared by AC power microarc oxidation

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science china(Technological sciences) 2009年第8期52卷 2195-2199页

作者： HUANG WenBo, LI WenFang & HAN Bing College of material science and engineering, South china University of Technology, Guangzhou 510640, china 1. College of material science and engineering South China University of Technology Guangzhou 510640 China

BaTiO3 films were prepared by microarc oxidation (MAO) with an in-house built alternating current (AC) power supply in Ba(OH)2 solution in this study. The surface morphology, combinability with the substrate and phase composition of the films were investigated by XRD, SEM and TEM. The BaTiO3 films were annealed at a temperature range of 900 to 1200℃ and phase compositions were tested thereafter. The results showed that the BaTiO3 films were mainly composed of the primitive hexagonal phase with relatively small amount of tetragonal and amorphous phases. Moreover, the amount of amorphous phase decreased with the time of annealing. The transformation of BaTiO3 from hexagonal structure to tetragonal stucture became obvious until the annealing temperature reached 1200℃. The film consisted mainly of BaTiO3 tetragonal structure with ferroelectric property. The influence of annealing on surface morphology and mechanism of phase transformation of the films were also discussed.

关键词： microarc oxidation ferroelectric film BaTiO3 annealing phase composition

Irradiation Damage of Oxide Dispersion Strengthened Ferritic Steel after Recrystallization

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International Journal of Minerals,Metallurgy and materials 1998年第3期12卷 160-164页

作者： Benfu Hu Shunmi Peng H Takahashi(material science and engineering School, University of science and Technology Beijing, Beijing 100083, china)(Faculty of engineering, Hokkado University, Sapporo 060, Japan) material science and engineering School University of Science and Technology Beijing Beijing 100083 China Faculty of engineering Hokkado University Sapporo 060 Japan

The evolution of secondary defects and the characteristics of the void swelling of electrons irradiated Oxide Dispersion Strengthened Ferritic Steels (ODS steels) after recrystallization were studied. It was found that recrystallization increases the void swelling of ODS steel as compared with solution and injected He+ + D+ *** are two size ranges of voids formed in recrystallized ODS steel during irradiation, and bubbles can be preferential sites for the void formation. Polycrystal with low density of defects is formed, and sites where point defects disappear by irradiation decrease. This is the main reason for the increase of void swelling of ODS steel after recrystallization.

关键词： ODS steel recrystallization, electron irradiation

Electrochemical Characteristic of Decarburization Reaction

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International Journal of Minerals,Metallurgy and materials 1999年第1期13卷 27-30页

作者： Xionggang Lu Fushen Li Lifen Li Kouchih Chou (Applied science School, University of science and Technology Beijing, Beijing 100083, china)(material science and engineering School, Shanghai University, Shanghai 200072, china) Applied science School University of Science and Technology Beijing Beijing 100083 China material science and engineering School Shanghai University Shanghai 200072 China

The electrochemical mechanism of the reaction between Fe-C melts and CaO-SiO2-Al2O3-FeOx slag systems has been carried out. The experimental results suggest that the final content of carbon in melt increases as the partial oxygen pressure of gas decreases no matter whether there is electronic conductor or not. However, the final content of carbon in the system with electronic conductor is much lower than that without electronic conductor. It can be deduced that the transfer ability of oxygen in slag is dominated by electrons. When an electronic conductor exists, an easy pathway for the electrons is provided and the oxygen transfer rate is accelerated.

关键词： melt-slag reaction decarburization electrochemistry electronic conductor

EFFECTS OF HEAT TREATMENT ON THE MICROSTRUCTURE OF Cu-Zn-Al (RE) SHAPE MEMORY ALLOYS

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 257-262页

作者： N.C. Si and S.C. Sun material science and engineering School, Jiangsu University of science and Technology, Jiangsu 212013, china Sch. of Mat. Sci. and Eng. Jiangsu Univ. of Sci. and Technol. Jiangsu 212013 China

The effects of heat treatment on the Cu-Zn-Al shape memory alloys with mixed REwere researched with the help of X-ray diffraction and transmission electron micro-scope (TEM).The results show that the shape memory alloys with martensite can beproduced by adding mixed RE and heat treatment processes holding at 820C -880Cfor 15min,quenching into oil,aging at 150C for 15min,and then holding in waterat 50C for *** alloys have the lowest transformation thermal *** the four experimental heat treatment processes the gradationally quenchingmakes the alloy have the highest transformation temperature and quenching into oilor water at room temperature makes the alloy have the largest thermal ***-crostructure examination shows that aging at 2000C could destroy the substructuresin lathy martensites in the alloy and form a lot of dislocations,and aging at 250℃could cause the bainite transformation in the alloy.

关键词： Cu-Zn-Al (RE) heat treatment transformation temperature thermoelastic martensite

One-pot synthesis of crystalline SnO_2 nanoparticles and their low-temperature ethanol sensing characteristics

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN YuJin1,2,3,ZHU ChunLing4,WANG LiJiao3 & WANG TaiHong2 1 School of materials science and engineering,Beijing Institute of Technology,Beijing 100081,china 2 Micro-Nano Technologies Research Center,Hunan University,Changsha 410082,china 3 College of science,Harbin engineering University,Harbin 150001,china 4 College of material science and Chemical engineering,Harbin engineering University,Harbin 150001,china School of materials science and engineering Beijing Institute of Technology Beijing 100081 China Micro-Nano Technologies Research Center Hunan University Changsha 410082 China College of science Harbin Engineering University Harbin 150001 China College of material science and Chemical engineering Harbin Engineering University Harbin 150001 China

Crystalline SnO2 nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

Synthesis and magnetic properties of CdS/α-Fe_2O_3 hierarchical nanostructures

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 997-1002页

作者： CHEN YuJin1,2,3, SHI XiaoLing1, CAO MaoSheng1 & ZHU ChunLing4 1 School of materials science and engineering, Beijing Institute of Technology, Beijing 100081, china 2 Micro-Nano Technologies Research Center, Hunan University, Changsha 410082, china 3 College of science, Harbin engineering University, Harbin 150001, china 4 College of material science and Chemical engineering, Harbin engineering University, Harbin 150001, china 1. School of materials science and engineering Beijing Institute of Technology Beijing 100081 China 2. Micro-Nano Technologies Research Center Hunan University Changsha 410082 China 3. College of science Harbin Engineering University Harbin 150001 China 4. College of material science and Chemical engineering Harbin Engineering University Harbin 150001 China

CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (230 K) than that of the single bulk α-Fe2O3 materials (263 K). Importantly, the hierarchical nanostructures exhibit weakly ferromagnetic characteristics at 300 K. A sharp peak assigned to the surface trap induced emission are observed in room temperature PL spectra. Combining with the optoelectronic properties of CdS, the CdS/ α-Fe2O3 hierarchical nanostructures may be used as multi-functional materials for optoelectronic and magnetic devices.

关键词： α-Fe2O3 CdS hierarchical nanostructures magnetic properties

Transformation Behaviour of Austenite in Steel under Condition of Stress-strain and Its Application

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Journal of materials science & Technology 1995年第6期11卷 440-442页

作者： Xu WANG Sigen WANG and Lixian HUA (dept. of materials science and engineering, University of science and Technology Beijing, Beijing, 100083, china) Beijing Univ of science and Technology Beijing China

Austenite can be retained at ambient temperature in steels by alloying and processing control. The transformation from austenite to martensite occurs under a certain conditions : thermal or deformation. Stress-strain induced martensitic transformation is important to improve the plasticity of steels which is called transformation induced plasticity (TRIP). Strength-ductility balance of the steels is greatly superior to that of other high strength steels due to the TRIP effect. A new type of steels-TRIP steel is developed

关键词： TRIP Transformation Behaviour of Austenite in Steel under Condition of Stress-strain and Its Application