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Journal of Rare Earths 2002年第5期20卷 385-387页

作者：于青唐瑜谭民裕 coll. of Chem. and Chem. eng. Lanzhou Univ. Lanzhou 730000 China

Six new rare earth complexes with Schiff base from 2,6 diformylpyridine N oxide and 4 amino antipyrine were synthesized. These complexes with general formula REL(NO 3) 3 (RE=La, Pr, Eu, Tb, Er, Y) were character... 详细信息

关键词： rare earths 2,6 diformypyridine N oxide 4 amino antipyrine Schiff base antimicrobial activity

Electroless Plating of Ni-Fe-P Alloy and Corrosion Resistance of the Deposit

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Journal of Materials Science & Technology 2005年第1期21卷 39-42页

作者： Senlin WANGcoll.ge of Materials Science and eng.neering, Huaqiao University, Quanzhou 362021, ChinaAssoc. Prof., Ph.D., coll. of Mat. Sci. and eng. Huaqiao Univ. Quanzhou 362021 China

Electroless Ni-Fe-P alloys in an alkaline bath were plated. The effects of deposition parameters on the plating rate and the coating composition were examined. The weight loss test and the anodic polarization measurement of the deposits in 3.5 wt pct NaCI solution (pH7.0) showed that the deposits with the mole ratio of NiS04/FeSO4 being 0.07:0.03, pH8.0 and 7.5 possess better corrosion resistance than that of the other deposits and the Ni-Fe-P deposits did not form passive films in this environment. In 5.0 wt pct NaOH solution, the Ni-Fe-P deposits have better corrosion resistance and formed passive films.

关键词： Nickel Iron Electroless deposition Anodic polarization

Entrapment of Inclusions in Diamond Crystals Grown from Fe-Ni-C System

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Journal of Materials Science & Technology 2002年第2期18卷 171-172页

作者： Yuxian LIU, Limei XIAO and Longwei YINcoll.ge of Materials Science and eng.neering, Shandong University, Jinan 250061, China [ Manuscript received June 28, 2001, in revised form October 18, 2001] coll. of Mat. Sci. and eng. Shandong Univ. Jinan 250061 China

Diamond single crystals grown from Fe-Ni-C system at high temperature-high pressure (HPHT) usually contain inclusions related to the metallic catalyst. During the diamond growth, the metallic inclusions are trapped by the growth front or are formed through reaction between the contaminants trapped in the diamond. In the present paper, the metallic inclusions related to the catalyst were systematically examined by transmission electron microscopy (TEM). The chemical composition and crystal structure of the metallic inclusions were for the first time determined by selected area electron diffraction pattern (SADP) combined with energy dispersive X-ray spectrometry (EDS). It is shown that the inclusions are mainly composed of orthorhombic FeSi2, fcc (FeNi)23C6, and orthorhombic Fe3C, hexagonal Ni3C.

关键词： Synthetic diamond Fe-Ni-C system Inclusion Transmission electron microscopy

Characterization of ZnO Based Varistor Derived from Nano ZnO Powders and Ultrafine Dopants

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Journal of Materials Science & Technology 2005年第2期21卷 183-186页

作者： Weizhong YANG, Dali ZHOU, Guangfu YIN, Runsheng.WANG and Yun ZHANG coll.ge of Material Science and eng.neering, Sichuan University, Cheng.u 610064, China coll. of Mat. Sci. and eng. Sichuan Univ. Chengdu 610064 China

Nanosized ZnO powders were prepared with a two-step precipitation method. The average size of ZnO particles was about 80 nm and their size distribution was narrow. Combining with ultrafine additive powders, ZnO base varistor was produced via an oxide mixing route. ZnO varistor derived from normal reagent grade starting materials was investigated for comparison purpose. Outstanding microstructure of the ZnO varistor derived from nanosize ZnO powders and ultrafine dopants was obtained: uniform distribution of fine ZnO grains (less than 3 microns), grain boundary and the dopant position. Higher varistor voltage (U=492 V/mm) and nonlinear coefficient (α=56.2) as well as lower leakage current (TL=1.5 μuA) were achieved. The better electrical properties were attributed to the uniform microstructure, which in turn led to stable and uniform potential barriers. Also this improved technique is more feasible for producing ZnO nanopowders and resulting varistor in large scales.

关键词： Zinc oxide (ZnO) Varistor Nanopowders Ultrafine dopants Two-step precipitation

Vacancies and Antisites in B2 FeAl and DO_3 Fe_3Al with a Modified Analytic EAM Model

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Journal of Materials Science & Technology 2001年第6期17卷 601-604页

作者： Xiaolin SHU, Wan gyu HU, Hanning XIAO and Huiqiu Deng.coll.ge of Materials Science and eng.neering, Hunan University, Changsha 410082, China Ban gwei ZHANG International Centre of Materials Physics, Chinese Academy of Sciences, S coll. of Mat. Sci. and eng. Hunan Univ. Changsha 410082 China

A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of ... 详细信息

A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of vacancy and antisite were also calculated. The present calculations are in agreement with the experimental data and the theoretical results obtained by other authors.

关键词： Al DO Fe Vacancies and Antisites in B2 FeAl and DO3 Fe3Al with a Modified Analytic EAM Model EAM

Effect of Nb on the Interfacial Wettability in Al_2O_3/Medium Mn Steel

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Journal of Materials Science & Technology 2003年第6期19卷 625-627页

作者： Sirong YU, Yaohui LIU and Zhenming HEcoll.ge of Materials Science and eng.neering, Jilin University, Changchun 130025, China coll. of Mat. Sci. and eng. Jilin Univ. Changchun 130025 China

To develop medium Mn steel (MMS) matrix composites reinforced by AI2O3 particles, the effect of Nb on the interfacial wettability of AI2O3/MMS and its mech.nism were investigated in this paper. The results show that the wetting angle of the specimens with different Nb contents are bigger than that of the specimen without Nb at the first stage, and then decreases with time at 1450℃. At certain time, the wetting angle is lower than that of the specimen without Nb. At 1550 and 1600℃, the wetting angle of the specimens containing Nb decreases quickly with time at first stage. After 10 min, the wetting angle reaches a steady state, and hardly changes with time. The mech.nisms of Nb to improve the wettability can be attributed to the enrichment of Nb at the interface and Nb serves as surface active agent of MMS at T1550℃, and reduces the interfacial energies.

关键词： Madium Mn steel A12O3 Nb Wettalility

New Developed Welding Electrode for Improving the Fatigue Streng.h of Welded Joints

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Journal of Materials Science & Technology 2002年第6期18卷 527-531页

作者： Wenxian WANG, Lixing HUO, Yufeng.ZHANG, Dongpo WANG and Hongyang JINGcoll.ge of Material Science and eng.neering, Tianjin University, Tianjin 300072, China coll. of Mat. Sci. and eng. Tianjin Univ. Tianjin 300072 China

A new welding electrode, low transformation temperature electrode (LTTE), was introduced in this paper. It was described in design principle, mech.nics, chemical compositions of their deposited metal and manufacturing methods. It was proved that the best transformation starting temperature from austenite to martensite of the deposited metal of LTTE was at about 191℃ and it was obtained by adding alloying elements such as Cr, Ni, Mn and Mo. The microstructure of the weld metal of the LTTE was low carbon martensite and residual austenite. The compressive residual stress was induced around the weld of the LTTE and the -145 MPa in compression could be obtained in middle of weld metal. The fatigue tests showed that the fatigue streng.h of the longitudinal welded joints welded with the LTTE at 2×106 cycles was improved by 59% compared with that of the same type of welded joints welded with conventional E5015 and the fatigue life was increased by 47 times at 162 MPa. It is a very valuable method to improve the fatigue performance of welded joints.

关键词： Low transformation temperature electrode Compressive residual stress Fatigue streng.h Welded joints

Synthesis and Crystal Structure of 4,6Di-tert-butyl-2-hydroxy-3-(N-1-phenylethyliminomethyl) phenyl bis(triphenylphosphine)palladium bromide

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Chinese Journal of Structural Chemistry 1999年第4期18卷 54-59页

作者： XU JiaXi\ ZHANG ZeYing\= (coll.ge of Chemistry and Molecular eng.neering, Peking University, Beijing 100871, China) coll. of Chem. and Molec. eng. Peking University Beijing 100871 China

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａｃｔｉｏｎｏｆｃａｒｂｏｎｃａｒ...

关键词： palladium complex synthesis molecular structure crystal structure

Application of Line Boundary Technique to 2D Tidal Current Simulation

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China Ocean eng.neering 1999年第4期14卷 399-410页

作者：宋志尧薛鸿超严以新 coll. Harbor Waterway/Coast. eng. Hohai University (HHU) Nanjing 210098 China coll. Harbor Waterway/Coast. eng. HHU Nanjing 210098 China

To deal with the problems concerning the shore boundary, moving boundary and eng.neering boundary which are encountered frequently in 2D tidal current simulation by the finite difference method, the concept of line boundary is introduced and studied here, and then the line boundary technique in common use is proposed in this paper. Analysis of some calculation cases shows that this technique is practical, effective, and simple in 2D tidal current simulation involving different boundaries.

关键词： line boundary technique shore boundary and eng.neering boundary moving boundary tidal current simulation

Properties of Ettringite Type Expansive Agent

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Journal of Wuhan University of Technology(Materials Science) 2001年第4期16卷 53-56页

作者：李悦 coll. of Architecture and Civil eng. Beijing Polytechnic University Beijing 100022 China

By employing different forms and amounts of materials, many kinds of ettringite type expansive agents had been prepared. The relationship between the compositions and properties of expansive agents was analyzed. The design methods of expansive agent have been put forward according to the property, requirement of expansive concrete.

关键词： ettringite expansive agent composition property