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chinese Journal of Polymer Science 2001年第4期19卷 399-405页

作者： Zhen-hua Yuan De-yan Shen Ren-yuan Qian Polymer Physics laboratory Center for Molecular Science, institute of Chemistry chinese academy of sciences,{3. china 中科院化学所高分子物理及化学国家重点实验室北京

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74-80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74 degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

SOME NONLINEAR APPROXIMATIONS FOR MATRIX-VALUED FUNCTIONS

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Journal of Computational Mathematics 2003年第6期21卷 801-814页

作者： Guo-liang Xu(academy of Mathematics and System sciences, chinese academy of sciences,{3. 100080, china) academy of Mathematics and System sciences Chinese Academy of Sciences 北京 100080

Some nonlinear approximants, i.e., exponential-sum interpolation with equal distance or at origin, (0,1)-type, (0,2)-type and (1,2)-type fraction-sum approximations, for matrix-valued functions are introduced. All these approximation problems lead to a same form system of nonlinear equations. Solving methods for the nonlinear system are discussed. Conclusions on uniqueness and convergence of the approximants for certain class of functions are given.

关键词： Matrix-valued function Nonlinear approximation Interpolation.

Follicular growth,differentiation and atresia

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chinese Science Bulletin 2003年第17期48卷 1786-1790页

作者： JIN Xuan & LIU Yixun State Key laboratory of Reproductive Biololgy, institute of Zoology, chinese academy of sciences,{3., china State Key laboratory of Reproductive Biololgy Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

Only limited numbers of primordial follicles in mammalian ovary grow and differentiate to reach the stage of dominate follicles and ovulate. 99% of the follicles in the ovary undergo atresia at various stages of development. Regulation of follicular growth, development and atresia is a complex process and involves interactions between endocrine factors and intraovarian regulators. This review summa-rized:ⅰ) FSH may not be a survival factor in regulating slow-growing preantral follicles. Some locally produced growth factors, activin and orphan receptors might play a more important role at this stage. ⅱ) Estrogen, activin/ inhibin and follistatin coordinate with FSH to regulate and control follicle differentiation. ⅲ) There are two types of follicular atresia induced by apoptosis which originates from GC or oocyte, respectively. Early translation of tPA mRNA into tPA protein in oocyte may be associated with oocyte apoptosis.

关键词：哺乳动物原始卵泡卵泡生长粒状细胞细胞分化

Superconductivity at 3. K in gadolinium-arsenide oxides GdO_(1-x)F_xFeAs

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Science china(Physics,mechanics & Astronomy) 2008年第6期51卷 719-722页

作者： CHENG Peng, FANG Lei, YANG Huan, ZHU XiYu, MU Gang, LUO HuiQian, WANG ZhaoSheng & WEN HaiHu national laboratory for Superconductivity, institute of Physics,{3., beijing 100190, china beijing national laboratory for Condensed Matter Physics, institute of Physics,{3., beijing 100190, china national laboratory for Superconductivity Institute of Physics Chinese Academy of Sciences Beijing China beijing national laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

In this paper we report the fabrication and superconducting properties of GdO1-xFxFeAs. It was found that when x is equal to 0.17, GdO0.83.0.17FeAs is a su-perconductor with the onset transition temperature Tcon ≈ 3..6 K. Resistivity anomaly near 13. K was observed for all samples up to x = 0.17, and such a phenomenon is similar to that of LaO1-xFxFeAs. Hall coefficient indicates that GdO1-xFxFeAs is conducted by electron-like charge carriers.

关键词： iron-based superconductor high-temperature superconductor

NONLINEAR FLUID DAMPING IN STRUCTURE-WAKE OSCILLATORS IN MODELING VORTEX-INDUCED VIBRATIONS

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Journal of Hydrodynamics 2009年第1期21卷 1-11页

作者： LIN Li-ming LING Guo-can WU Ying-xiang ZENG Xiao-hui Division of Engineering sciences Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China The State Key laboratory of Nonlinear mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

A Nonlinear Fluid Damping （NFD） in the form of the square-velocity is applied in the response analysis of Vortex-Induced Vibrations （VIV）. Its nonlinear hydrodynamic effects on the coupled wake and structure oscillators are investigated. A comparison between the coupled systems with the linear and nonlinear fluid dampings and experiments shows that the NFD model can well describe response characteristics, such as the amplification of body displacement at lock-in and frequency lock-in, both at high and low mass ratios. Particularly, the predicted peak amplitude of the body in the Griffin plot is in good agreement with experimental data and empirical equation, indicating the significant effect of the NFD on the structure motion.

关键词： Vortex-Induced Vibration (VIV) Nonlinear Fluid Damping (NFD) wake oscillator

Anomalous Hall effect in perpendicular CoFeB thin films

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chinese Physics B 2014年第4期23卷 9-17页

作者：朱涛 institute of Physics and beijing national {3. for Condensed Matter Physics Chinese Academy of Sciences

Our recent research achievements in the perpendicular magnetic anisotropy （PMA） properties of the CoFeB sand- wiched by MgO and tantalum layers are summarized. We found that the PMA behaviors of Ta/CoFeB/MgO and MgO/CoFeB/Ta thin films are different. The larger PMA in the latter film is related to the lower magnetization of CoFeB deposited on MgO. Furthermore, we have demonstrated a large anomalous Hall effect in perpendicular CoFeB thin fihn. Our results show large anomalous Hall resistivity, large longitudinal resistivity, and low switching field can be achieved, all at the same time, in the perpendicular CoFeB thin film. Anomalous Hall effect with high and linear sensitivity is also found in an MgO/CoFeBFFa thin film with a thick MgO layer, which opens a door tbr future device applications of perpendicular ferromagnetic thin films.

关键词： anomalous Hall effect perpendicular magnetic anisotropy magnetic properties of interfaces

ON THE EXPLICIT COMPACT SCHEMES II: EXTENSION OF THE STCE/CE METHOD ON NONSTAGGERED GRIDS ON THE EXPLICIT COMPACT SCHEMES II: EXTENSION OF THE STCE/CE METHOD ON NONSTAGGERED GRIDS

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Journal of Computational Mathematics 2000年第5期18卷 467-480页

作者： Hua-zhong Tang , Hua-mu Wu (State Key laboratory of Scientific and Engineering Computing, institute of Computational Mathematics, chinese academy of sciences,{3., china) 中科院计算数学所科学与工程计算国家重点实验室北京 100080

This paper continues to construct and study the explicit compact (EC) schemes for conservation laws. First, we axtend STCE/SE method on non-staggered grid, which has same well resolution as one in [1], and just requires half of the computational works. Then, we consider some constructions of the EC schemes for two-dimensional conservation laws, and some 1D and 2D numerical experiments are also given.

关键词： Conservation laws Compact scheme Shock-Capturing method Euler equations.

Strong decays of N~*(153.) in an extended chiral quark model

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Science china(Physics,mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3.& ZOU BingSong1,2,3.1 institute of High Energy Physics,chinese academy of {3.,beijing 100049,china 2 Theoretical Physics Center for Science Facilities,chinese academy of {3.,beijing 100049,china 3.Graduate University of chinese academy of sciences,beijing 100049,china institute of High Energy Physics Chinese Academy of Sciences Beijing China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2,3.& LI Gaicheng1,2,3.1. Engineering Research Center for Information Security Technology, institute of Software, chinese Aca- demy of sciences,{3., china 2. beijing Zhongke Ansheng Corporation of Information Technology,{3., china 3. Graduate School of the chinese academy of sciences, beijing 10003., china Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing China beijing Zhongke Ansheng Corporation of Information Technology Beijing China Graduate School of the chinese academy of sciences Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

Synthesize TiO_2 microspheres self-assembled from nanorods via hydrothermal treatment

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Science china Chemistry 2007年第2期50卷 175-178页

作者： ZHANG YiBing1,2,FENG XinJian3.& JIANG Lei2,3.1 Shangrao Teachers’ College,Shangrao 3.4001,china 2 national Center for Nanoscience and Nanotechnology,beijing {3.,china 3.institute of Chemistry,chinese academy of sciences,beijing {3.,china Shangrao Teachers’ College Shangrao China national Center for Nanoscience and Nanotechnology Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China

The TiO2 microspheres were deposited on the glass substrates under certain conditions via hydro-thermal reaction using 0.15 mol·L?1 TiCl3.saturated NaCl aqueous solution adding urea as an additive. The TiO2 is characterized rutile by results of SEM,TEM and XRD techniques,the TiO2 microspheres are large scale assembled from TiO2 nanorods. The affections on the products by the factors of the con-tents of urea being an additive(the key techniques) ,the reaction temperature,the reaction time and the concentration of TiCl3.were studied. The optimum condition was found,and the mechanism of reac-tions was discussed also.

关键词： TiO2 self-assembly nanorods microsphere hydrothermal reaction