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Chinese Journal of Aeronautics 2024年第8期37卷 373-387页

作者： Xin SHI Xiang guo Tao SUO Yingtao YUAN Hongli he Zhiyong REN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China International Research Laboratory of Impact Dynamics and its Engineering Application Xi’an 710072China institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China Chinese Flight Test Establishment Xi’an 710089China

This paper proposes a measurement method related to the braking deformation of a complex *** the braking process,the deformation of the wheel includes large amounts of movement,vibration,warping,and distortion.A novel subset assignment and correlation method is proposed to measure the complex *** proposed method can greatly improve the accuracy and stability of the calculation of complex deformations by simplifying the complex deformation into translational deformations in logarithmic coordinate *** to the simulation and actual experiments,the proposed method can be utilized to measure the deformations of up to 100%tensile strain under complex *** to the accuracy verification experiment,the error of the proposed method is less than 50 *** results show that the proposed method can effectively carry out structural deformation measurement in the complex motion and deformation *** proposed method has great significance for structural performance analysis and optimization design considering complex motion and deformation.

关键词： Complex deformation Measurement Digital image correlation Aircraft braking Deformation field

In situ reproductive organs of Early Cretaceous ferns from Northeast china

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Chinese Science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and CheN Fen1. Research {2. of Petroleum and Development, beijing 100083 2. china University of Geosciences, beijing 100083, china Research institute of Petroleum and Development Beijing china University of Geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of Northeast{2., whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and heilongjiang of Northeast{2.. The study focuses on 35 species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： Northeast china Early Cretaceous Filicopsida in situ reproductive organs.

Microstructure and Frictional Behavior of Fe-based Amorphous Metallic Coatings Prepared by Atmospheric Plasma Spraying

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稀有金属材料与工程 2011年第S3期40卷 160-165页

作者： Zhou Zheng1,2. Wang Lu2. he Dingyong1, Liu Yanbo2. Zhang Guanzhen1 1 beijing University of Technology, beijing 10012., china 2.beijing institute of Technology, beijing 100081, china beijing Univ Technol Beijing 100124 Peoples R China beijing Inst Technol Beijing 100081 Peoples R China

Amorphous metallic coatings with a composition of Fe48Cr15Mo14C15B6Y2.were prepared by means of atmospheric plasma spraying (APS) process under different conditions. The microstructure and frictional behavior were characterized simultaneously in this article. The results show that the as-deposited coatings consist of amorphous matrix and some precipitated nanocrystals, while the amorphous fraction and particle deformation as well as crystallization mechanism are significantly sensitive to the spraying parameters. The amorphous coatings express high microhardness and excellent wear resistance under dry frictional wear condition, which attributes to the inherent characteristic of amorphous phase and the dispersion strengthening of precipitated nanocrystals. The dominant wear mechanism of the amorphous coatings is fatigue wear accompanying with oxidative wear. In addition, the microhardness and wear resistance of the amorphous coatings were improved by optimizing spraying parameters, owing to the effect of both structural character and proper proportional of amorphous and nanocrystals fraction.

关键词： Fe-based amorphous coating APS microstructure friction

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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Science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2. LIU Caishan2.& CheN Bin2.1. {2. institute of Graphic Communication, {2. 102.00, china 2. Department of Mechanics & Engineering Science, Peking University, {2. 100871, china beijing institute of Graphic Communication Beijing China Department of Mechanics & Engineering Science Peking University Beijing China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG xiaoxia~(1,2. & guo Maoz{2.ng~(1,3) 1. School of Mat{2.matical Sciences,Peking University,beijing 100871,china 2. Department of Mat{2.matics,Yantai University,Yantai 2.4005,china 3. LMAM,Peking University,beijing 100871,china School of Mathematical Sciences Peking University Beijing China Department of Mathematics Yantai University Yantai China LMAM Peking University Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2. )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2. ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

Proteomics in china:Ready for prime time

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Science china(Life Sciences) 2010年第1期53卷 22-33页

作者： GAO Xue1,ZHANG XueLi1,ZheNG JunJie1 & he {2.2.1 State Key Laboratory of Proteomics,beijing Proteome Research Center,beijing institute of Radiation medicine,beijing 102.06,china 2.institutes of Biomedical Sciences,Fudan University,Shanghai 2.0032.china State Key Laboratory of Proteomics Beijing Proteome Research Center Beijing Institute of Radiation Medicine

Proteomics is a newborn science focusing on the comprehensive systematic analysis of all proteins in molecule machineries,organelles,cells,tissues,organs or intact *** has been becoming one of the focuses in life sciences and cutting-edge techniques in biotechnologies in the 2.st *** the last decade,proteomics in china has developed much faster than other developing fields in the life *** review article briefly retrospects the origin and development of proteomics in china,and provides an overview of representative scientific progress and perspectives.

关键词： proteomics progress china Human Proteome Organization Human Liver Proteome Project perspectives

A circum-earth shear zone at low-latitudes and episodic large earthquakes in it and the circum-Pacific seismic zone

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Science china Earth Sciences 2006年第9期49卷 897-903页

作者： MA Zongjin1, DU Pinren1, REN Jinwei2.& GAO Xianglin1 1. institute of Geology, china Earthquake Administration, {2. 10002., china 2. institute of Earthquake Science, china Earthquake Administration, {2. 100036, china institute of Geology China Earthquake Administration Beijing China institute of Earthquake Science China Earthquake Administration Beijing China

Because of the differential motions between the Northern and Southern hemispheres of the Earth, there exists a motion discordant zone between them. On the surface this zone consists of 13 large faults dominant with strike-slip. We call it a global shear zone at low-latitudes (E system). By statistical analysis of temporal distribution of earthquakes Mw≥7.5 in the E system and the circum-Pacific (P system) during 1900―2.03, we find that there exist quasi-episodic and alternative activities in and between these two systems. This phenomenon is likely associated with the half-sphere oscillation in dilation and contraction and the change of the Earth’s rotation rate.

关键词： shear zone, circum-Pacific zone, great earthquake, quasi-episode.

Bioinformatics analyses for signal transduction networks

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Science china(Life Sciences) 2008年第11期51卷 994-1002页

作者： LIU Wei1,2. LI Dong2. ZHU YunPing2.& he fuchu1.2.1 College of Mechanical & Electronic Engineering and Automatization, National University of Defense Technology, Changsha 410073,{2. 2.State Key Laboratory of Proteomics, beijing Proteome Research Center, beijing institute of Radiation medicine, beijing 102.06,{2. College of Mechanical & Electronic Engineering and Automatization National University of Defense Technology Changsha 410073 China

Research in signaling networks contributes to a deeper understanding of organism living activities. With the development of experimental methods in the signal transduction field, more and more mechanisms of signaling pathways have been discovered. This paper introduces such popular bioin-formatics analysis methods for signaling networks as the common mechanism of signaling pathways and database resource on the Internet, summerizes the methods of analyzing the structural properties of networks, including structural Motif finding and automated pathways generation, and discusses the modeling and simulation of signaling networks in detail, as well as the research situation and tendency in this area. Now the investigation of signal transduction is developing from small-scale experiments to large-scale network analysis, and dynamic simulation of networks is closer to the real system. With the investigation going deeper than ever, the bioinformatics analysis of signal transduction would have immense space for development and application.

关键词： signal transduction structural motif automated pathways regeneration dynamics simulation

Existence of solutions for the dynamic equation of ferrimagnets

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Progress in Natural Science:Materials International 2007年第11期17卷 1279-1283页

作者： Zeng Ming1, guo Boling2.and Cheng Caozong1(1. College of Applied Sciences, {2. University of Technology, {2. 10002., china 2. Center for Nonlinear Studies, institute of Applied Physics and Computational Mathematics, {2. 100088, china) College of Applied Sciences Beijing University of Technology Beijing 100022 China

Ferrimagnet is a kind of basic and important multi-sublattice magnet material. It has attracted more and more attention of physicists and mathematicians. Many results of solitons and numerical computations on this topic have appeared. In this article, the dynamic equation for an isotropic ferrimagnet with two non-equivalent sublattices is studied, existence of weak solutions in multi dimension case is proved through the penalized method, the uniqueness and smoothness of the solution in one dimension case are also obtained by the relation between this equation and hyperbolic equation.

关键词： ferrimagnet weak solutions penalized method finite difference method

Human hepatopoietin augmenter of liver regeneration──A hepatotrophic factor for liver regeneration, and its potential antihepatitis effect in vivo

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Chinese Science Bulletin 1998年第12期43卷 1026-1031页

作者： YANG Xiaoming 1, WANG Aimin 2. ZHOU Ping 3, XIE Ling 1, WANG Qingming 1, WU Zuze 1 and he fuchu 1 1. {2. of Radiation medicine, beijing 100850, china 2. No. 2.2.Hospital of PLA, Baoding 071000, china 3. General Hospital of the Air institute of Radiation medicine Beijing China No. 2.2.Hospital of PLA Baoding China General Hospital of the Air Force of PLA Beijing China

The effect of human hapatopoietin i.e. augmenter of liver regeneration (hALR) was determined on hepatocyte DNA synthesis, and on CCl 4-induced hepatitis in animal in vitro and in vivo. It is found that ALR could directly stimulate DNA synthesis of hepatocytes in primary culture in a dose-dependent manner. In 30% hepatectomied rats, significant DNA synthesis occurred in control rats ; even so, exogenous hALR gene encoding protein increased DNA synthesis of regeneration liver by 2.3 fold compared with control rats. A lower dose of CCl 4 was administrated in rats and the effect of ALR on DNA synthesis of regenerating liver 48 h after CCl 4 administration was analyzed. Few Budr-labeled hepatocytes were visible in control rats. However, exogenous hALR markedly increased the number of labeled cells in a dose-dependent manner. Statistical analysis showed that 10 or 40 μg·kg -1 ALR protein stimulated DNA synthesis by 1.7 and 4.8 fold respectively. In addition to enhancing cell growth, adiministration of hALR achieved a significant improvement in reversing the lethality of rat hepatic failure when compared with that of control group; the elevation of cytosolic enzymes was dramatically suppressed by exogenous hALR in CCl 4-treated mice in vivo and in vitro; histologically, hepatocytes around the central vein were necrotic, and the degree of hepatocyte necrosis in control mice was more prominent than that in the mice given 40 μg·kg-1 hALR 48 h after CCl 4 administration. We also noted that hALR had a strong antihepatitis effect in vitro which was determined with primary cultured rat hepatocytes. These findings suggest that hALR protects the integrity of hepatocytes against severe hepatitis, and indicate that ALR may be an important regulator of liver regeneration and play a major role in liver injury repair. It proves ALR adminstration to be a useful treatment to accelerate liver regeneration and to prevent the onset of hepatitis or intrahepatic cholestasis induced by toxin.

关键词： liver regeneration hepatopoietin DNA synthesis hepatitis.