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STUDIES ON THE PORE FORMATION MECHANISM OF β-CRYSTALLINE POLYPROPYLENE UNDER STRETCHING

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Chinese Journal of Polymer Science 2004年第2期22卷 123-130页

作者：徐懋 State Key Laboratory of Polymer Physics and Chemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The pore formation mechanism of β-crystalline polypropylene under stretching was investigated. The porosity of the samples increases rapidly with stretching, having a maximum at draw ratios around 2 and then decreases monotonically. An abrupt formation process of initial micropores at very low draw ratios was evidenced by in situ SAXS measurements. At the same time the phase transition from β-crystal to α-crystal proceeds slowly in the whole deformation process up to large draw ratios around 5. Comparative studies of α-and β-crystalline polypropylene samples before stretching indicate that in addition to difference in crystal forms the α-and β-crystalline polypropylene samples exhibit quite different morphological features. There are a lot of interfaces in β-crystalline polypropylene samples, which may have a lower density value and can be easily etched by argon ions and penetrated by small molecules. It was concluded from these experimental facts that the pore formation and crystal transition are two independent phenomena during the deformation of β-crystalline polypropylene samples, and phase transition from β-crystal to α-crystal could hardly be the origin of pore formation. A defect initiation mechanism was proposed to understand the pore formation behavior of β-crystalline polypropylenes.

关键词： Pore formation under stretching β-crystalline polypropylene Mechanism

Study on healthcare magnetic concrete

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Rare Metals 2006年第Z1期25卷 562-567页

作者： YANG Yushan DONG Faqin FENG Jianjun School of Material Science and Engineering Southwest University of Science and Technology Mianyang 621010 China School of Material Science and Engineering Southwest University of Science and Technology Mianyang 621010 China People''s Hospital of Mianyang Mianyang 621000 China

Magnetic concrete was prepared by adding SrFe12O9 magnetic functional elementary material into concrete, and its magnetism was charged by magnetizing machine. The effect of SrFe12O9 content on magnetic field intensity and the attenuation of magnetic field intensity were investigated in different medium. The blood viscosity of rats kept in magnetic concrete was carried out. The results show that magnetic concrete can be prepared by adding SrFe12O9, and magnetic fields intensity increases with the augment of ferrite content. The attenuation of magnetic fields is mainly related with the density of medium, but it is secondary to the properties of medium. The blood viscosity of rats decreases under magnetic condition, but the blood cells remain the same as before. Experimental results support that magnetic concrete has great healthcare function.

关键词： SrFe12O9 concrete magnetic field healthcare

Intelligent modeling and optimization on time-sharing power dispatching system for electrolytic zinc process

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中国有色金属学会会刊：英文版 2000年第4期10卷 561-565页

作者：王雅琳桂卫华阳春华黄泰松中南工业大学湖南长沙

Based on real time price counting of electric power, an optimization model of time sharing power for electrolytic zinc process(EZP) was established by means of an incremental fuzzy neural network(FNN), which is adopted to approximate the relationship of current efficiency, current density and acidity. Penalty function introduced and optimal objective function reconstructed, a single loop simulated annealing algorithm(SAA) by using mutation and extending searching spaces was used to obtain optimal time sharing power scheme. Industrial practical results show that the whole system can greatly decrease the power consumption of EZP and increase the time sharing profits.

关键词： fuzzy neural network optimization model of time sharing power simulated annealing algorithm

Optimum linear array of an optical aperture synthesis telescope

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Chinese Science Bulletin 2002年第23期47卷 1964-1968页

作者： WEN Jianguo JIN Shengzhen NING Shunian National Astronomical Observatory Chinese Academy of SciencesBeijing 100012China China University of Mining and Technology Beijing 100083China

Measuring out successively the degree of coherence of the source produced by any couple of the small apertures via rotating an array composed of the small aperture telescopes, and synthesizing them into the (u, v) coverage of the source, the brightness distribution of the source can be obtained by the inverse Fourier transform of the degree of coherence with much higher resolution than from a single telescope. This article discusses the arrangements of the small apertures in the linear array, and found a method to decide the quality of the arrangements, the judgment factorε is introduced to calculate the arrangements in quantity. There are 1.5x1011 possibilities for 11 apertures. Therefore, the computer procedures are programmed to select the optimum arrangements. The effect of the simulation of the aperture synthesis is given for the linear array. The simulation method can also be used in the nonlinear arrays.

关键词： optical aperture synthesis optimum linear array judgment factor (u v)-spectrum sampling point spread function.

Measuring observability by generalized information theoretic quantities

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控制理论与应用（英文版） 2008年第3期6卷 233-238页

作者： Badong CHEN Jinchun HU Hongbo LI Zengqi SUN State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China

A normalized measure is established to provide the quantitative information about the degree of observability for the discrete-time, stochastically autonomous system. This measure is based on the generalized information theoretic quantities （generalized entropy, mutual information） of the system state and the observations, where the system state can be a discrete or a continuous random vector. Some important properties are presented. For the linear case, the explicit formula for the degree of observability is derived, and the equivalence between the proposed measure and the traditional rank condition is proved. The curves for the degree of observability are depicted in a simple example.

关键词： Stochastic system Observability Information theory

Coupling microchip electrophoresis with MALDI-TOF-MS based on a freezing technique

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Chinese Chemical Letters 2013年第6期24卷 491-493页

作者： Lei Nie Guo-Bin Xu Xiao-Yan Wang Yun Liu Peng-Yuan Yang Department of Chemistry Fudan University Institutes of Biomedical Sciences of Shanghai Medical College Fudan University

A freezing technique protocol was proposed for coupling microchip electrophoresis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALD1-TOF-MS）.The microfluidic flow was frozen immediately after electrophoresis on microfluidic chip and the separated analyte molecules were kept in their zone pattern in the ***,the frozen-chip was lyophilized and sent into TOF-MS instrument as a MALDI target,and the analyte molecules in the microfluidic channels were subjected to analysis by mass *** approach could eliminate sample cross-contamination, providing a new interface for microchip electrophoresis and MALDI-MS.

关键词： Microchip electrophoresis MALDI-TOF-MS Peptide analysis Freezing technique

Joint Optimization of Channel Allocation,Link Assignment and Power Control for Device-to-Device Communication Underlaying Cellular Network

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China Communications 2015年第12期12卷 92-100页

作者： TANG Rui ZHAO Jihong QU Hua School of Electronics and Information Engineering Xi'an Jiaotong University School of Communication and Information Engineering Xi'an University of Posts and Telecommunications

Device-to-Device(D2D) communication has been proposed to facilitate cellular network with system capacity(SC) and quality of service(QoS).We consider the design of link assignment(LA),channel allocation(CA)and power control(PC) in D2D-aided content delivery scenario for both user fairness(UF)and system throughput(ST) under QoS *** to the complexity of the problem,we decompose it into two components:CA is formulated from graph perspective to mitigate severe co-channel interference,which turns out to be the Max K-cut problem;LA and PC are jointly optimized to utilize the gain achieved from CA for supreme performance,and specifically,genetic algorithm(GA) is adopted to optimize LA,but when deriving the fitness of each chromosome,PC optimization will be *** to numerical results,we elucidate the efficacy of our scheme.

关键词： decompose utilize links formulated constraint facilitate optimize requirement fitness throughput

Interface and properties of epoxy resin modified by elastomeric nano-particles

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Science China Chemistry 2005年第2期48卷 148-155页

作者： HUANG Fan1, LIU Yiqun1, ZHANG Xiaohong1, GAO Jianming1, SONG Zhihai1, TANG Banghui1, WEI Genshuan2 & QIAO Jinliang1 1. SINOPEC Beijing Research Institute of Chemical Industry, Beijing 100013, China 2. Institute of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100080, China Correspondence should be addressed to Qiao Jinliang (email: jqiao@***.) SINOPEC Beijing Research Institute of Chemical Industry Beijing China Institute of Applied Chemistry College of Chemistry and Molecular Engineering Peking University Beijing China

Study on a new composite of epoxy resin/elastomeric nano-particles (ENP) is re- ported in this paper, which shows that, in comparison with pure epoxy resin and epoxy toughened with CTBN, the composites of epoxy resin/carboxylic nitrile-butadiene ENP and epoxy resin/styrene butadiene vinyl-pyridine ENP possess both higher toughness and heat resistance. Both ENPs used in the study have an average size of less than 100 nm. Study on the epoxy network’s morphology and interface properties suggests that due to the chemical reaction be- tween ENP and epoxy resin and more hydrogen bonds between nitrile groups of the rubber and hydroxyl groups of the epoxy resin, stronger interaction at the larger interface may lead to the observed excellent properties of the epoxy resin toughened with ENP.

关键词： elastomeric nano-particles, epoxy resin, carboxylic nitrile-butadiene rubber, styrene butadiene vinyl-pyridine rubber, interface.

TURNING-OVER OF THE ELECTRIC DIPOLE IN A POLYMER

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Chinese Journal of Polymer Science 2001年第6期19卷 573-578页

作者： Guang-qi Li Xin Sun and Sheng Li State Key Laboratory of Surface Physics and Research Center for Theoretical Physics, Fudan University Shanghai 200433, China National Laboratory of Infrared Physics, Shanghai Institute of Technical Physics,Shanghai 200083, China Stt. Key Lab. of Surface Physics Res. Center for Theoretical Physics Fudan University Shanghai 200433 China Natl. Laboratory of Infrared Physics Shanghai Inst. of Technical Physics Shanghai 200083 China

The transition from the biexciton to the exciton can turn over the direction of the electric dipole of a polymericmolecule. This turning-over action combined with the photoinduced polarization reversion can be used as a switch. Theswitching speed is governed by the relaxation time of the turning-over process, which can be determined by a dynamicalsimulation.

关键词： exciton biexciton electric dipole switch relaxation