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Trend and Development of Semi-Solid metal Processing

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Journal of Materials Science & Technology 2000年第5期16卷 453-460页

作者： Xianfeng PAN, Haifeng ZHANG, Aimin WANG, Bingzhe DING, Keqiang QIU and Zhuangqi HU (state key {2. of Rapidly Solidified Nonequilibrium Alloys, Institute of {3. research, Chinese Academy of Sciences, Shenyang 110015, China) state key {2. of Rapidly Solidified Nonequilibrium Alloys Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

This paper reviewed the trend and development of semi-solid metal technique. The processes and mechanisms for producing slurry of SSM and its industrial applications have been summarized and discussed. Discussions on the basic rheological theory are presented for more applications. Further consideration of the development and application of SSM technique is also proposed.

关键词： SSM Trend and Development of Semi-Solid metal Processing

BEHAVIOUR OF INITIATION AND GROWTH OF SHORT FATIGUE CRACKS

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Acta metallurgica Sinica(English Letters) 1996年第1期9卷 65-70页

作者： WU Zhixue XU Hao(Institute of Mechanical Engineering,Northeastern university,Shenyang 110006,China)(Fushun Petroleum institute,Fushun 113.01.China).(state {2. {3. for Fatigue and Fracture of Materials,Institute of metal research,Chinese Academy of Northeastern Univ Shenyang China

Rotary bending fatigue tests were carried out using smooth specimens of a medium-carbon steel with two different grain *** process of early crack development was observed by the replica method,and the effects of grain size and microstructure on short crack development were *** was shown that the initiation process of fatigue cracks is that the damaged region is intensified gradually,and the growth of short cracks relates to the coalescence of *** grain size and microstructure have a great influence upon the initiation and growth of short cracks.A reasonable definition was given in relation to short fatigue crack initiation and propagation.

关键词： fatigue damage crack initiation crack propagation microstructure

Effect of Pb, Hg and Cd in soil on scavenging system of activated oxygen in tobacco leaves

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Chinese Science Bulletin 1999年第S2期44卷 91-93页

作者： YAN Chongling~(1,2., HONG Yetang~1, WANG Shijie~1, LIN Peng~3. YANG Xianke~2. FU Shunzhen~2. ZHU {3.ong~2.and WU Shanqi~2.1. state {3. laboratory of Environmental Geochemistry, Chinese Academy of Sciences, Guiyang 550002. China 2. Guizhou Institute of Environmental Protection, Guiyang 550002. China 3. Department of Biology, Xiamen university, Xiamen 3.1005, China state key {2. of Environmental Geochemistry Chinese Academy of Sciences Guiyang 550002 China Guizhou Institute of Environmental Protection Guiyang 550002 China Department of Biology Xiamen University Xiamen 361005 China

Pb, Hg and Cd will affect human health by vegetative chain. In recent years, people more and more are concerned about heavy metal pollution of the soil-plant system. Many researchers studied the effect of single heavy metal on growth, photosynthesis, respiration and quality of plants, but few systematicstudies of the effect of heavy metals on the scavenging system of activated oxygen of plants. This note systematically studies the effect of Pb, Hg and Cd in soil on the scavenging system of activated oxygen in tobacco leaves. 1 Material and methods Material: Tobacco (Nicoticana tabacum L). Methods: Cultivating and measuring methods were according to reference. 2.Results Results of this study indicate that the common effect of Pb, Hg and Cd on activity of CAT is obvi-

关键词： Pb Hg and Cd scavenging system of activated oxygen tobacco.

The crystal structure of a novel basket binuclear silver (Ⅰ) cryptate

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Chinese Journal of Chemistry 1994年第2期12卷 190-192页

作者： YU, Shu-Yan LUO, Qin-Hui SHEN, Meng-Chang ZHANG, Zheng Coordination Chemistry state key {2.,{3., nanjing, Jiangsu 2.0008, ChinaHUANG, Xiao-Ying WU, Qiang-JinFuzhou state key {2. of Structural Chemistry, Fuzhou, Fujian 3.0002. China

The metal complexes of polyaza cryptand have attracted much attentionowing to their special structure, unusual photo-chemical, electrical and catalyticproperties. Recently, Lehn and Nelson synthesized successively a series ofcryptands and crypatates with high yield by (2.3. schiff-base condensation of tris(2.aminoethyl)amine and aryl dialdehyde. But so far, little work about the analogueswith larger cavities and flexible chains condensed by tris (3.aminopropyl) amine (abbr.

关键词： Silver cryptate binuclear crystal structure basket-type.

Microstructure and Phase Stability of Plasma Sprayed Sc_2._3.Y_2._3.ZrO_2.TBCs

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稀有金属材料与工程 2011年第S4期40卷 151-154页

作者： Li Q L1,Liu H F1,2.Yang W H1,Li S Q1,Chen H J1,3.National key laboratory of Science and Technology on Power Beam Processes,Beijing Aeronautical Manufacturing Technology {2. Institute,Beijing 10002.,China 2.3. key laboratory of Powder metallurgy,Central South university,Changsha 410083.China 3.10} key laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan university of Technology,Wuhan 43.063. China. Beijing Aeronaut Mfg Technol Res Inst Natl Key Lab Sci & Technol Power Beam Proc Beijing 100024 Peoples R China Cent S Univ State Key Lab Powder Met Changsha 410083 Peoples R China Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430063 Peoples R China

Scandia,yttria-stabilized zirconia (Sc2.3.Y2.3.ZrO2. powder for plasma spraying was synthesized by chemical co-precipitation *** morphology and phase stability of plasma sprayed 6.8mol%Sc2.3.1.2.ol%Y2.3.ZrO2.thermal barrier coatings (TBCs) were *** of the coatings were heated at 1400℃ for 500 hours and then examined by X-ray *** was found that the Sc2.3.Y2.3.ZrO2.coatings showed excellent phase stability to retain single tetragonal t' phase structure and did not undergo a tetragonal-to-monoclinic phase transition upon cooling.

关键词： thermal barrier coatings Scandia yttria-stabilized zirconia microstructure phase stability

In Vitro Biomineralization of Glutaraldehyde Crosslinked Chitosan Films

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Journal of Wuhan university of Technology(Materials Science) 2005年第2期20卷 20-23页

作者：冯芳 state key {2. of {3. Matrix Composites Shanghai Jiaotong University Shanghai 200030China Lecturer

The biomimetic approach was applied to study the in vitro biomineralization of series of the chitosan films crosslinked by glutaraldehyde. The deposited calcium phosphate coatings were studied using scanning electron microscopy and energy dispersive X-ray analysis. Initially, the treatment in simulated body fluid (SBF) results in the formation of single layer of calcium phosphate particles over the film surface. As immersion time in SBF increases, further nucleation and growth produce a simulated calcium phosphate coating. The Ca/P molar ratio of the calcium phosphate increases with the immersion time, showing a rapid formation of calcium-deficient phosphate material from the phase of octac1alcium phosphate. The different glutaraldehyde crosslinking degree influences the morphology and magnitude of the calcium phosphate coatings on the surface of the chitosan films.

关键词： chitosan calcium phosphate biomimetic mineralization

Fractionation of Heavy metals in Sediments from Dianchi Lake,China

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Pedosphere 2007年第2期17卷 265-272页

作者： LI Ren-Ying YANG Hao ZHOU Zhi-Gao Lü Jun-Jie SHAO Xiao-Hua JIN Feng state key {2. of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. College of Geography Science Nanjing Normal University Nanjing 210097 （China） Department of Applied Meteorology Nanjing University of Information Science ＆ Technology Nanjing 210044 （China）

Fractionation of heavy metals in sediments can help in understanding potential hazards of heavy metals. The present study analyzed total concentrations and fractions of selected heavy metals （Cd, Cr, Cu, Pb, and Zn） in surface sediments from Dianchi Lake, Yunnan Province, China, as well as factors that may affect distributions of the various heavy metal fractions. Total concentrations of the heavy metals decreased in the order Zn 〉 Cu 〉 Pb 〉 Cr 〉 Cd. These heavy metals, except Cr, were much higher than their background levels, indicating that Dianchi Lake was polluted by Cd, Zn, Pb, and Cu. Cadmium occurred mainly as the non-residual fraction （sum of the HOAc-soluble, reducible, and oxidizable fractions）（97.6%）, and Zn （55.7%） was also predominantly found in the non-residual fraction. In contrast, most of the Cr （88.5%）, Pb （81.8%）, and Cu （59.2.） occurred in the residual fraction. Correlation analysis showed that total heavy metal concentrations, organic matter and reducible Fe were the main factors affecting the distributions of the various heavy metal fractions. In the Walhai section of Dianchi Lake （comprising 97% of the lake area）, the concentrations of Cd, Zn, Pb, and Cu in the non-residual fraction were significantly lower （P ≤ 0.01 or 0.05） than those of the Caohal section （3. of the lake area）. This indicated that potential heavy metal hazards in the Caohai section were greater than the Waihai section.

关键词： Dianchi Lake heavy metal fractions lake sediment organic matter reducible Fe

Effects of icosahedral phase formation on the microstructure and mechanical improvement of Mg alloys:A review

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Progress in Natural Science:Materials International 2012年第5期22卷 364-385页

作者： D.K.Xu,E.H.Han state key {2. for Corrosion and Protection,Institute of {3. research,Chinese Academy of Sciences,62.Wencui Road,Shenyang 110016,China state key {2. for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences 62 Wencui Road Shenyang 110016 China

Icosahedral phase(I-phase) is a relatively excellent strengthening phase in Mg *** on their volume fraction,the yield strength of Mg-Zn-Y-Zr alloys can vary from 150 to 450 MPa at room ***,the formation of I-phase has been considered as one of the most effective methods for developing high strength lightweight Mg alloys for automotive and aerospace *** this review article,a series of research work about I-phase containing Mg alloys have been systematically investigated including I-phase formation mechanism and their effects on mechanical properties of Mg *** emphases have been given to:(1) Structure of I-phase and its orientation relationship with the a-Mg matrix.(2. Influence of alloying elements and solidification conditions on I-phase formation.(3. Effects of I-phase on microstructural evolution and mechanical improvement of Mg-Zn-Y-(Zr) ***,the applications of I-phase for the mechanical improvement of other Mg alloys such as AZ91 and super-lightweight Mg-Li alloys are also reviewed.

关键词： Icosahedral phase Mg alloys Mechanical properties Microstructural evolution

Electrical Resistance Measurement of Glass Transition and Crystallization Characteristics of Zr-Al-Cu-Ni metallic Glasses

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Journal of Materials Science & Technology 2002年第6期18卷 492-496页

作者： Yaping WANG and Ke LUstate key {2. for RSA, Institute of {3. research, Chinese Academy of Sciences, Shenyang 110016, China Chinese Acad Sci Met Res Inst State Key Lab RSA Shenyang 110016 Peoples R China

In this paper, glass transition and thermal stability of the Zr-AI-Cu-Ni metallic glasses were investigated by using electrical resistance measurement (ERM), DSC and X-ray diffraction techniques. The experimental results show that the ERM is capable of detecting the glass transition of the amorphous alloys and can help to distinguish the crystallization products of the Zr-AI-Cu-Ni metallic glasses owing to the difference of the electrical resistivity between the precipitation phases.

关键词： Zr-Al-Cu-Ni metallic glasses Electrical resistance Glass transition Crystallization