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Effect of VFe addition on hydrogen storage behavior of TiMn_(1.5)-based alloys

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Journal of University of Science and technology Beijing 2004年第3期11卷 263-267页

作者： Xuebin Yu Zhu Wu Baojia Xia Taizhong Huang Jinzhou Chen Naixin Xu Lab of Energy Science and technology, shanghai {2. of microsystem and information technology, chinese Academy of sciences, shanghai 2.0050, china Lab. of Energy Sci. and Technol. Shanghai Inst. of Microsystem Chinese Acad. of Sci. Shanghai 200050 China

The hydrogen absorption and desorption behavior of TiMn_(1.2.)Cr_(0.2.)alloys with VFe substitution for partial Mn was investigated at 2.3, 2.3 and 313 K. It is found thatVFe substitution increases their hydrogen storage capacity, decreases the plateau pressure and thehysteresis factor of their pressure-composition-temperature (PCT) curves. After annealing treatmentat 12.3 K for 6 h, TiMn_(0.95)Cr_(0.2.)(VFe)_(0.3) alloy exhibits a lower hydrogen desorptionplateau pressure (0.2. MPa at 313 K) and a smaller hysteresis factor (0.13 at 313 K); the maximumand effective hydrogen storage capacities (mass fraction) are 2.03% and 1.12. respectively, whichcan satisfy the demand of hydrogen storage tanks for proton exchange membrane fuel cells (PEMFC).

关键词： TiMn-based alloy hydrogen storage capacity hysteresis sloping factor PEMFC

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 Normal University, shanghai 2.0062. china 2. Ion Beam Lab, shanghai institute of Mini-system and information, chinese Academy of sciences,shanghai 2.0050, china 3. Department of Electronics, School of information Science and {12., East china Normal 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.

Suppressed Antiferromagnetism and Superconductivity in As-deficient Iron-based Superconductor of SrFe_(1.8)Co_(0.2.As_x

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稀有金属材料与工程 2011年第S3期40卷 358-361页

作者： Liu Zhiyong1, Lu Yuming1, Liu Jinlei1, Qu Chunqing1,2.3, Chen Changzhao1, Cai Chuanbing1, Huang Fuqiang3, Xie Xiaoming2.1 shanghai University, shanghai 2.0444,{2. 2.State Key Laboratory of Functional Materials for Informatics,shanghai institute of microsystem and information technology,chinese Academy of sciences,shanghai 2.0050,{2. 3 shanghai institute of Ceramics, chinese Academy of sciences, shanghai 2.0050,{2. shanghai Univ Res Ctr Superconductors & Appl Technol Shanghai 200444 Peoples R China chinese Acad Sci Shanghai Inst Microsyst & Informat Technol State Key Lab Funct Mat Informat Shanghai 200050 Peoples R China chinese Acad Sci Shanghai Inst Ceram Shanghai 200050 Peoples R China

Iron-based superconductors namely Sr(Fe1.8Co0.2.As1.8 (FeAs1.8) and Sr(Fe1.8Co0.2.As1.85 (FeAs1.85) with As deficiency are prepared by solid-state reaction. X-ray diffraction reveals that the polycrystalline phase forms in the studied samples, identical to typical SrFe2.s2.(12.) matrix. Resistive and magnetic measurements show that the superconducting transition temperatures (Tc) are about 19 K for both FeAs1.8 and FeAs1.85. Compared with the performances of typical iron-based 12. superconductors arising from Co doping, the present samples show the suppressed superconductivity. Moreover, the antiferromagnetic (AFM) phase correlated with spin-density-wave (SDW) is reduced as well. The AFM transition temperature decreases to 12. K for FeAs1.85, while such a phase transition is absent at all for FeAs1.8, one sample with less As, implying that the existence of SDW and antiferromagnetism is more sensitive to As content.

关键词： antiferromagnetism superconductivity iron-based superconductors

Channel characterization at 12. GHz for future indoor communication systems

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chinese Physics B 2013年第5期22卷 650-656页

作者：陈镇曹俊诚 Key Laboratory of Terahertz Solid-State technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences

We present a simulation on the spatial and temporal characteristics of the indoor propagation channel at 12. GHz. The simulation, applied to a dynamic scenario with randomly placed objects and moving people in a room, is based on a three-dimensional ray-tracing method. Propagation and reflection mechanisms of electromagnetic waves are discussed in the channel model. The received power in a 0.95-m-height plane is obtained. Comparison between walls and ceiling covered with dielectric mirrors and those with three common wall and ceiling materials are presented. The result shows that the holistic received power level with dielectric mirrors is about 10 dB higher than with other materials.

关键词： sub-terahertz communication channel models ray tracing electromagnetic propagation

Tunneling conductance in graphene ferromagnet/p wave superconductor junctions

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Science china(Physics,Mechanics & Astronomy) 2012年第4期Mechanics & Astronomy) .卷 649-653页

作者： LI XiaoWei 1,2.,CHEN HuaBao 1 & LIU ShuJing 1 1 School of Physics and Electronic Electrical Engineering,Huaiyin Normal University,Huaian 2.3300,china 2.State Key Laboratory of Functional Materials for Informatics,shanghai {2. of microsystem and information technology,chinese Academy of sciences,shanghai 2.0050,china 1. School of Physics and Electronic Electrical Engineering Huaiyin Normal University Huaian 223300 China2. State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Using the extended Blonder-Tinkham-Klapwijk formalism,we investigate the conductance spectra of graphene ferromagnet/p wave superconductor *** is found that the conductance spectra are affected by the p wave pairing *** ferromagnetic exchange energy in the ferromagnet can suppress Andreev retroreflection but enhance the specular Andreev reflection in graphene ferromagnet/p wave superconductor *** conductance decreases with increasing exchange energy Eh for EhEF.

关键词： graphene ferromagnet p wave superconductor tunneling conductance

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science china(information {2.) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2.SUN LiXin 1,LI Yong 2.& JIA ShiLou 3 1 School of Computer Science and Telecommunication Engineering,Jiangsu University,Zhenjiang 2.2.13,china 2.Research Center for Wireless Communication,shanghai {2. of microsystem and information technology,chinese Academy of sciences,shanghai 2.0050,china 3 Communication Research Center,Harbin {2. of technology,Harbin 150001,china 1. School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

Cytotoxicity of carbon nanotubes

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Science china Chemistry 2008年第11期51卷 1021-1029页

作者： ZHU Ying1,2.& LI WenXin1 1 Laboratory of Nano-biology and Medicine, shanghai institute of Applied Physics, {2. Academy of sciences, shanghai 2.1800, china 2.Graduate School of {2. Academy of sciences, Beijing 100049, china 1. Laboratory of Nano-biology and Medicine Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of chinese Academy of sciences Beijing 100049 China

With large-scale production and application at large scale, carbon nanotubes (CNTs) may cause ad-verse response to the environment and human health. Thus, study on bio-effects and safety of CNTs has attracted great attention from scientists and governments worldwide. This report briefly summa-rizes the main results from the in vitro toxicity study of CNTs. The emphasis is placed on the descrip-tion of a variety of factors affecting CNTs cytotoxicity, including species of CNTs, impurities contained, lengths of CNTs, aspect ratios, chemical modification, and assaying methods of cytotoxicity. However, experimental information obtained thus far on CNTs' cytotoxicity is lacking in comparability, and some-times there is controversy about it. In order to assess more accurately the potential risks of CNTs to human health, we suggest that care should be taken for issues such as chemical modification and quantitative characterization of CNTs in cytotoxicity assessment. More importantly, studies on physical and chemical mechanisms of CNTs' cytotoxicity should be strengthened; assaying methods and evaluating criteria characterized by nanotoxicology should be gradually established.

关键词： carbon nanotubes (CNTs) cell bio-security

Waiting time in block fading MIMO systems with dynamic-depth interleaving

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Science china(information {2.) 2010年第8期53卷 1622-1627页

作者： GUO HaiYou 1,2., HU HongLin 1,2.& ZHANG Yan 3 1 Key Laboratory of Wireless Sensor Network & Communication, shanghai institute of {2. and information technology, chinese Academy of sciences, shanghai 2.0050, china 2.shanghai Research Center for Wireless Communications, shanghai 2.0335, china 3 Simula Research Laboratory, Lysaka 132., Norway 1. Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China2. Shanghai Research Center for Wireless Communications Shanghai 200335 China3. Simula Research Laboratory Lysaka 1325 Norway

Interleaving is an efficient measure to resolve the bursty errors in a block fading multiple-inputs multiple-outputs (MIMO) system. For the metrics of network layer, interleaving exerts two conflicting effects on the ultimate delay performance. Specifically, interleaving can advantageously reduce data transmit time. On the other hand, it comes at a cost, entailing an undesired delay penalty resulting from interleaving depth. Here, we exploit a unified model to accommodate these two conflicting effects, and derive the average waiting time in block fading MIMO systems with dynamic-depth interleaving. Such a unified model is developed with a combined method of both information theory and queueing theory. Therefore, the model is capable of characterizing the randomness of data arrival process, hence the nature of dynamic-depth interleaving. The methodology and the results are applicable to designing, evaluating, and tuning the practical interleaving systems.

关键词： dynamic-depth interleaving multiple-inputs multiple-outputs (MIMO) queueing analysis waiting time

Ultrafast excitation relaxation in light-harvesting complex LH2.from *** 601

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Science china Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2. LIU Yuan3, LIU Weimin2. GUO Junhua1, XU Chunhe3 & QIAN Shixiong2.1. School of Physics and information Optoelectronics, Henan University, Kaifeng 475001, china 2. Physics Department, Fudan University, {2. 2.0433, china 3. {2. institute of Plant Physiology, chinese Academy of sciences, {2. 2.0032. china 1. School of Physics and information Optoelectronics Henan University 475001 Kaifeng China 2. Physics Department Fudan University 200433 Shanghai China 3. shanghai institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2.from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783 nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.35 ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.