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science china(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2.1 department of materials {2. and {4.,Nanjing university of {2. and Technology,Nanjing 2.0094.china 2.College of materials {2. and {4.,Southeast university,Nanjing 2.1189,china 1. department of materials {2. and engineering Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Anticoagulation property and security of artificial heart valve material

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science china(Technological sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,2., 3, ZHANG Feng2. LI Changrong2. YU Liujiang2. ZHENG Zhihong2. WANG Xi2. JIANG Zhenbin4. CHEN Anqing4.& XU Jingfang3 1. department of Physics, East china {2. university, Shanghai 2.0062. china 2. Ion Beam Lab, Shanghai Institute of Mini-system and information, Chinese Academy of {14.s,Shanghai 2.0050, china 3. department of Electronics, School of Information {14. and Technology, East china {2. Univer- sity, Shanghai 2.0062. china 4. Shanghai Cardiovascular Institute, Zhongshan Hospital, Shanghai 2.0032. china 1. department of Physics East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. department of Electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. Shanghai Cardiovascular Institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2.million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

Study on Green Residential Space Design

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IJLAI Transactions on Science and Engineering

IJLAI Transactions on science and engineering 2024年第1期2卷 32-37页

作者： Yu Jiang Shenyang normal university No.2.3 Huanghe North Street Shenyang 110034China

With the ever-changing nature,green ecology has become an international trend of ***,the green ecological design of residential space has become the main melody of people’s *** always implement the concept of ecological and environmental protection in the design process,attach importance to the ecological effect of residential space,carry out reasonable budget and use of environmentally friendly decorative materials,reduce the waste of materials,save money and save resources at the same time,and protect the *** the same time,people began to put their hopes on the residential space design,which made the green residential space design began to *** the bold exploration and practice of designers,the design of green residential space will be endowed with more distinctive characteristics and unique *** from the concept of green design,this paper explores the method of green space design through typical analysis.

关键词： Green Residential space Haze

Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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science china(Technological sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3, LOU Decheng1, GAO Zhanjun4. LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3 & MA Mingzhen1,2.1. Key Laboratory of Metastable materials science & Technology of Hebei, Yanshan {2., Qinhuangdao 066004.{4. 2. National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001,{4. 3. College of Mechanical engineering, Yanshan {2., Qinhuangdao 066004.{4. 4. Chinese Academy of engineering, Beijing 100038,{4. 1. Key Laboratory of Metastable materials science & Technology of Hebei Yanshan University 066004 Qinhuangdao China 2. College of Mechanical engineering Yanshan University 066004 Qinhuangdao China 3. Chinese Academy of engineering 100038 Beijing China 4. National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology 150001 Harbin China

Mechanical properties of the Zr4.Ti14.u12.5Ni10Be2..5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-32.0 machine at 34. and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr4.Ti14.u12.5Ni10Be2..5 bulk amorphous alloy, mechanical properties, compressive deformation.

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan university Journal of Natural sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2.3 , ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3,5 1. Institute of Mountain Hazards and Environment, Chinese Academy of sciences , Chengdu 61004., Sichuan, china 2. Graduate {2. of Chinese Academy of sciences, Beijing 10004., china 3. Sichuan Institute of Land Resource Management, Chengdu 61004., Sichuan , china 4. department of Resources and Environment science, Sichuan normal {2. , Chengdu 610061, Sichuan, china 5. College of Information engineering, Chengdu {2. of Technology, Chengdu 610059, Sichuan, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China department of Resources and Environment science Sichuan Normal University Chengdu Sichuan China College of Information engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2.02. the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

The steady-state solution of dendritic growth from the undercooled binary alloy melt with the far field flow

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science china(Technological sciences) 2009年第8期52卷 2280-2287页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun2.3,4.1 School of Applied sciences, {4. of science and Technology Beijing, Beijing 100083, china 2.School of materials science and engineering, {4. of science and Technology Beijing, Beijing 100083, china 3 School of Mathematical sciences, Nankai {4., Tianjin 300071, china 4.department of Mathematics and Statistics, McGill {4., Montreal H3A 2.6, Canada School of Applied sciences University of Science and Technology Beijing Beijing 100083 China School of materials science and {2. University of Science and Technology Beijing Beijing 100083 China School of Mathematical sciences Nankai University Tianjin 300071 China department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The steady-state dendritic growth from the undercooled binary alloy melt with the far field flow is considered. By neglecting the interface energy, interface kinetics and buoyancy effects in the system, we obtaine the steady-state solution for the case of the large Schmidt number, in terms of the multiple variable expansion method. The changes of the temperature and concentration fields, the morphology of the interface, the normalization parameter and the Peclet number of the system induced by uniform external flow are derived. The results show that, compared with the system of dendritic growth from undercooled pure melt, the convective flow in the system of growth from undercooled binary alloy has stronger effects on the morphology of the interface. Nevertheless, the shape of the interface still remains nearly a paraboloid.

关键词： binary alloy melt convection dendritic growth interfaces steady-state solution multiple variable expansion method

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4.5 1 Key Laboratory of Beam Technology & materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing normal {2., Beijing {4., china 2.Beijing Radiation Center, Beijing {4., china 3 Laboratory of Optical Physics, Institute of Physics, Chinese Academy of sciences, Beijing 100080, china 4.Key Laboratory of Advanced materials of the Ministry of Education, department of materials science and engineering, Tsinghua {2., Beijing 100084. china 5 Beijing National Center for Electron Microscopy, Tsinghua {2., Beijing 100084. china 1. Key Laboratory of Beam Technology & materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. Beijing Radiation Center Beijing 100875 China 3. Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. Key Laboratory of Advanced materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. Beijing National Center for Electron Microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4., and Mn3+ ions are partly converted into Mn2. and Mn4. due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4. was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4.; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4.. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

The evolution and morphological stability of a spherical crystal

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science china(Technological sciences) 2008年第3期51卷 225-243页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun3,4.1 School of Applied sciences, university of science and Technology Beijing, Beijing 100083, china 2.School of materials science and engineering, university of science and Technology Beijing, Beijing 100083, china 3 School of Mathematical sciences, Nankai university, Tianjin 300071, china 4.department of Mathematics and Statistics, McGill university, Montreal H3A 2.6, Canada 1. School of Applied sciences University of Science and Technology Beijing Beijing 100083 China 2. School of materials science and {2. University of Science and Technology Beijing Beijing 100083 China 3. School of Mathematical sciences Nankai University Tianjin 300071 China 4. department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The growth model of a spherical crystal in the undercooled melt including the surface energy, interfacial kinetics and convective flow is established. The effect of the convective flow induced by a small far field flow on the evolution and morphological stability of the interface of the spherical crystal is studied. The interface shape of the spherical crystal, which is affected by the far field flow, and the dispersion relation of the growth rate of amplitude of the perturbed interface are derived. It is shown that the convection induced by the far field flow makes the interface of the growing spherical crystal further grow in the upstream direction of the far field flow and inhibit growth in the downstream direction; the interface of the decaying spherical crystal further decays in the upstream direction and inhibits decay in the downstream direction. The theoretical result suggests that both the growth of the sphere in the upstream direction and the decay of the sphere in the downstream direction make the spherical crystal tend to evolve into an oval; the morphological stability of the interface depends on a certain radius R c such that the spherical crystal is unstable when its radius is greater than R c and stable when its radius is less than R c . The surface energy and interfacial kinetics have strong stabilizing effects on the growth of the spherical crystal. In the meantime interfacial kinetics is a table factor of the interface when the interface of the sphere is growing; it is an unstable factor of the interface when the interface is decaying.

关键词： solid-liquid interface spherical crystal convective flow crystal growth morphological stability

SOME THERMODYNAMIC PROPERTIES OF Pd-In ALLOYS

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 311-317页

作者： YL. Chen(department of materials {2. and engineering, Zhejiang {4., Hangzhou 31002., china) Zhejiang Univ Hangzhou China

Some thermodynamic parnmeters of Pd-In alloys with 2.to 70 at. H indium have been determined in the temperuture range 800 to 1000℃ from e.m.f measurements ongalvanic cells with an onsen-cotzducting solid electrolyte. Heats of tnising calculated hem the activities are in excellent agreement with calorimetric data. The relative partial excess hee enengy of indiurn assumes unnsually larpe negative values ap to-174.J/mol for Pd-rich alloys. Two efficts are discussed to account for the non-idealproperties: The rise Of Fermi enerpy as the valence electron8 of indium enter the 4.and 5sP bands of the alloy and the lattice distortion brought about by the differentmolar volumes of the cofnponents. The rise of the Fermi enerpy, as determlned fromthe activity data, indicates a strict adherence of the alloys to the rigid band model.

关键词： galvanic cell activity data Fermi energy,lattice distortion rigid band model

Effects of Ca substitution and surface treatment on electrochemical performances of Ml_(1.0-x) Ca_xNi_(4.0) Co_(0.6) Al_(0.4. hydrogen storage alloy electrodes

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中国有色金属学会会刊：英文版 1999年第3期9卷 487-492页

作者： Chen Weixiang(陈卫祥) 1, Qi Jianqin(祁建琴) 1, Chen Changpin(陈长聘) 2.1. department of Physics 2. department of materials science and engineering, Zhejiang {2., Hangzhou 31002., P. R. china Zhejiang Univ Dept Phys Hangzhou 310027 Peoples R China Zhejiang Univ Dept Mat Sci & Engn Hangzhou 310027 Peoples R China

The influences of Ca substitution for Ml and surface treatment on electrochemical performances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4.hydrogen storage alloy electrode were investigated. Ca substitution with x 2.for Ml could improve its discharge capacity, but Ca substitution with x >0.2.could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these properties of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4.alloy electrode, the alloy was treated in 6 mol/L KOH+0.02.mol/L KBH 4.solution. The results showed that the surface treatment improves the electrochemical performances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. :The influences of Ca substitution for Ml and surface treatment on electrochemical performances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4.hydrogen storage alloy electrode were investigated. Ca substitution with x 2.for Ml could improve its discharge capacity, but Ca substitution with x >0.2.could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these properties of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4.alloy electrode, the alloy was treated in 6 mol/L KOH+0.02.mol/L KBH 4.solution. The results showed that the surface treatment improves the electrochemical performances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode.

关键词： hydrogen storage alloy electrode Ca substitution surface modification