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Recent progress of solar physics research in china

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Research in Astronomy and Astrophysics 2011年第12期11卷 1377-1402页

作者： Cheng Fang 1 School of Astronomy and Space Science,Nanjing University,Nanjing 210093,china.2 Key laboratory of modern Astronomy and Astrophysics(Nanjing University),Ministry of Education,china School of Astronomy and Space Science Nanjing University Nanjing 210093 China Key laboratory of modern Astronomy and Astrophysics (Nanjing University) Ministry of Education China

Owing to the largely improved facilities and working conditions, solar physics research in china.has recently shown marked development. This paper reports on the recent progress of solar physics research in china.s Mainland, mainly focusing on several hot issues, including instrumentations, magnetic field observations and research, solar flares, filaments and their eruptions, coronal mass ejections and related processes, as well as active regions and the corona, small-scale phenomena, solar activity and its predictions. A vision of the future is also described.

关键词： Sun: general -- Sun: coronal mass ejections (CMEs) -- solar physics:recent progress

Theoretical research progress in new-generation Internet architecture

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Science in china.Series F) 2008年第11期51卷 1634-1660页

作者： WU JianPing1,2,3,LIU Ying2,3 & WU Qian2,3 1 Department of Computer Science,Tsinghua University,Beijing 100084,china.2 Network Research Center,Tsinghua University,Beijing 100084,china.3 Tsinghua national laboratory for Information Science and Technology(TNList) ,Beijing 100084,china 1. Department of Computer Science Tsinghua University Beijing 100084 China 2. Network Research Center Tsinghua University Beijing 100084 China 3. Tsinghua national laboratory for Information Science and Technology (TNList) Beijing 100084 China

Internet has become the most important information infrastructure supporting modern socio-economic development, social progress and technological Innovation. Invented 30 years ago, today Internet is facing increasingly severe technical challenges. This paper introduces the progress of the major international newgeneration Internet research plans; analyzes its basic characteristics and the principal contradictions during the development; detsiledly introduces the research carried out by 973 Project ＂Research of Future Internet Architecture＂ on the key scientific issues of new-generation Internet architecture and its latest research results; and looks to the future of the research-focus faced with the new situations of the basic research of new-generation Internet architecture as well as the new demands of innovative applications on Internet architecture.

关键词： new-generation Internet network architecture multi-dimension scalability

Joint segmentation and motion estimation of left ventricle with an anisotropic biomechanical model

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Progress in Natural Science:Materials International 2007年第02期17卷 226-229页

作者： ZHUANG Ling, LIU Huafeng, BAO Hujun ( State Key laboratory of CAD & CG, Zhejiang University, Hangzhou 310027, china.State Key laboratory of modern Optical Instrumentation, Zhejiang University, Hangzhou 310058, china. [a]State Key laboratory of CAD&CG Zhejinang University Hangzhou China [b]State key laboratory of modern Optical Instrumentation Zhejiang University Hangzhou China

Accurate estimation of shape and motion variability of the heart has important clinical implications for heart disease diagnosis. In this paper, we describe a framework which performs simultaneous segmentation and motion analysis of the left ventricle from 3D cardiac images. The left ventricle is formulated as an anisotropic linear elastic body represented by a set of tetrahedrons constructed from sampling nodes. The elastic body is evolved by both internal force and external force, and the external force imposed on each node is an integration of edginess measure, shape coherence measure, prior distributions of the myocardial tissues and temporal driven measure. The displacement field and the segmentation result are simultaneously solved at the equilibrium state between the internal energy and the external energy. The experiment with 3D canine MR images illustrated its abilities and benefits.

关键词： left ventricle motion simultaneous estimation deformable model image segmentation.

A NEW WELL TEST MODEL FOR STRESS-SENSITIVE AND RADIALLY HETEROGENEOUS DUAL-POROSITY RESERVOIRS WITH NON-UNIFORM THICKNESSES

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Journal of Hydrodynamics 2011年第6期23卷 759-766页

作者： ZHANG Lie-hui, GUO Jing-jing, LIU Qi-guo State Key laboratory of Reservoir Geology and Exploitation, Southwest Petroleum University, chengdu 610500, china State Key laboratory of Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China

This article presents a new well test model for stress-sensitive composite dual-porosity reservoirs based on the concept of permeability modulus, where the rock and fluid properties as well as the formation thickness vary in the radial direction. An analytical solution in the Laplace space for the pressure-transient behavior for a line-source, constant-rate well of this type of reservoir is obtained with the Laplace transformation and the perturbation technique. The pressure and its derivative in the reservoir and the effects of relevant parameters on the pressure-transient response are obtained. The model as well as the corresponding type curves may be used in predicting the production performance or analyzing the production data for this type of reservoir.

关键词： non-uniform thickness stress-sensitive composite dual-porosity well test model type curve

High geo-stress distribution and high geo-stress concentration area models for eastern margin of Qinghai-Tibet plateau

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Science china.Technological Sciences) 2011年第S1期54卷 154-166页

作者： HUANG RunQiu,WANG YunSheng,WANG ShiTian & LI YuSheng State Key laboratory of Geo-hazard Prevention and Geo-environment Protection,chengdu University of Technology,chengdu 610059,china 1. State Key laboratory of Geo-hazard Prevention and Geo-environment Protection Chengdu University of Technology Chengdu 610059 China

High geo-stress and its engineering problems have severely affected the development of civil infrastructures in western china. The problems include high rock slope instabilities,rock burst,gas explosion and large-scale soft rock deformation in deep *** paper investigates the distribution of the high geo-stresses and the models of the stress concentration areas in the eastern margin of Qinghai-Tibet plateau so that a solid foundation can be formed to address the *** investigation is based on a comprehensive analysis of the previous research data of the eastern margin and uses remote sensing techniques,geophysics,geochemistry,and large scale geological surveying *** investigation has found that some special tectonic zones have high *** high geo-stresses are located at(1) the convergent boundary areas between two fault blocks with large strength differences,(2) the tectonic necks in front of active fault blocks,and(3) the intersection and/or termination areas of faults within the fault *** example for(1) is the north Qilian high geo-stress *** example for(2) is the Minshan high geo-stress area in the northwest ***,the investigation has summarized six basic models to characterize the high geo-stress concentration *** first one is the convergent stress concentration model at the boundary of two fault *** other five stress concentration modes are oblique fissures or intersecting areas,areas without lower velocity layer in the crust,areas of compression induced tensile cracking,tectonic wedge areas,and tectonic neck areas,respectively.

关键词： high geo-stress geo-stress concentration model regional geo-stress distribution Qinghai-Tibet plateau

The reliability of the improved e^N method for the transition prediction of boundary layers on a flat plate

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Science china.Physics,Mechanics & Astronomy) 2012年第5期55卷 837-843页

作者： SU CaiHong1,2 1 Department of Mechanics,Tianjin University,Tianjin 300072,china.2 Tianjin Key laboratory of modern Engineering Mechanics,Tianjin 300072,china 1. Department of Mechanics Tianjin University Tianjin 300072 China2. Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300072 China

The transition criterion in the improved eN method is that transition would occur whenever the velocity amplitude of disturbance reaches 1%-2% of the free stream velocity,while in the conventional eN method,the N factor is an empirical *** this paper the reliability of this key assumption in the improved eN method is checked by results of transition prediction by using the Parabolized Stability Equations(PSE).Transition locations of an incompressible boundary layer and a hypersonic boundary layer at Mach number 6 on a flat plate are predicted by both the improved eN method and the PSE *** from both methods agree fairly well with each other,implying that the transition criterion proposed in the improved eN method is reliable.

关键词： transition prediction boundary layer eN PSE

Effects of the tyrosine protein kinase inhibitor genistein on the proliferation,activation of cultured rat hepatic stellate cells

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World Journal of Gastroenterology 2002年第4期8卷 739-745页

作者： Xiao-Jing Liu Ming-Hui Huang laboratory of Department of Internal Medicine,West china.Hospital,Sichuan University,chengdu 610041,Sichuan Province,china.Li Yang Qiong Wang Yi-Ping Wang Department of Gastroenterology of West china.Hospital,Sichuan University,chengdu 610041,Sichuan Province,china.Yong-Qiu Mao Center for Cancer Biotherapy of West china.Hospital,Sichuan University,chengdu 610041,Sichuan Province,china.Hong-Bin Wu laboratory of Department of Surgery,West china.Hospital,Sichuan University,chengdu 610041,Sichuan Province,china laboratory of Department of Internal Medicine West China Hospital Sichuan University 37 Wainan Guoxueshang Chengdu 610041 Sichuan Province China. xiaojingliu67@***

AIM: Hepatic stellate cell (HSC) plays a pivotal role inliver fibrosis and is considered as the therapeutic targetfor the treatment of hepatic fibrosis. Tyrosine proteinkinase plays an important role in the proliferation,activation of HSC. The purpose of the study is toinvestigate the effects of the tyrosine protein kinaseinhibitor genistein onthe proliferation and activationof cultured rat HscMETHODS: Rat HSC were isolated from Wistar rats by insitu perfusion of collagenase and pronase and single-stepdensity Nycodenz gradient. Culture-activated HSC wereserum-starved and incubated with 10-3 to 10-5 mol/Lconcentration of genistein for 24, 48 or 72 h. In PDGF-induced HSC proliferation, HSC were stimulatel with L0μg@L-1PDGF-BB for 15 min, and then treaeed with genisteinfor the same time. Cell proliferation was measured byMTr assay and based on flow cytometric analysis of cellcycle. The a-smooth muscle actin (α-SMA) expression inHSC was studied with confocal laser microscopy and flowcytometry. c-fos c-jun and cyclin D1 expression in HSCwas also detected by flow ***: Genistein inhibited basal and PDGF-inducedproliferation of HSC at the concentration of 10-8 to 10-5mol/L, and treatment with 10-7 mol/L concentration ofgenistein for 48 h inhibited the HSC proliferationsignificantly (the inhibition rate was 70.3 %, P＜0.05).Immunofluorescence detected by confocal lasermicroscopy and flow cytometry showed that treatmentwith 10-7 mol/L genistein for 48 h suppressed theexpression of α-SMA significantly in HSC (the specificfluorescence intensity were 60.2±21.5 vs 35.3±11.6and 12.8± 10.4 vs9.54±6.39, respectively, both P＜0.05).The intensity of c-fos, c-jun and cydin D1 expression ofHSCs treated with 10-7 mol/L genistein for 48 h wasalso significantly decreased compared with the ***: Genistein influences proliferation of HSC,suppresses the expression of α-SMA in HSC and tinhibits the intensity of c-fos, c-jun and cyclin D1expression of HSCs. Genistein

关键词：酪氨酸激酶抑制剂肝星形细胞肝纤维化细胞活化细胞增殖动物实验

A first-principles investigation into the hydrogen bond interaction in β-HMX

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Science china.Physics,Mechanics & Astronomy) 2010年第6期53卷 1080-1085页

作者： CHEN Fang 1 ,ZHANG Hong 1,2,ZHAO Feng 3 ,MENG ChuanMin 3 & CHENG XinLu 1 1 Institute of Atomic and Molecular Physics,Sichuan University,chengdu 610065,china.2 School of Physical Science and Technology,Sichuan University,chengdu 610065,china.3 laboratory for Shock Wave and Detonation Physics Research,Southwest Institute of Fluid Physics,china.Academy of Engineering Physics,Mianyang 621900,china 1. Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China2. School of Physical Science and Technology Sichuan University Chengdu 610065 China3. Laboratory for Shock Wave and Detonation Physics Research Southwest Institute of Fluid Physics China Academy of Engineering Physics Mianyang 621900 China

A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12 -2p orbits,between H19 -1s and O28 -2p orbits of intra molecules,and between H19 -1s and O24 -2p orbits of inter molecules. The Mulliken population analysis is also made.

关键词： structural property hydrogen bond β-HMX population analysis

Thermal-mechanical coupled effect on fracture mechanism and plastic characteristics of sandstone

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Science china.Technological Sciences) 2007年第6期50卷 833-843页

作者： ZUO JianPing1,2, XIE HePing2,3, ZHOU HongWei1,2 PENG SuPing1 1 State Key laboratory of Coal Resources and Safe Mining, china.University of Mining and Technology, Beijing 100083, china.2 Institute of Rock Mechanics and Fractals, china.University of Mining and Technology, Beijing 100083, china.3 Sichuan University, chengdu 610065, china 1. State Key laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing 100083 China 2. Institute of Rock Mechanics and Fractals China University of Mining and Technology Beijing 100083 China 3. Sichuan University Chengdu 610065 China

Scanning electronic microscopy (SEM) was employed to investigate fractographs of sandstone in mine roof strata under thermal-mechanical coupled effect. Based on the evolution of sandstone surface morphology in the failure process and frac- tography, the fracture mechanism was studied and classified under meso and mi- cro scales, respectively. The differences between fractographs under different tem- peratures were examined in detail. Under high temperature, fatigue fracture and plastic deformation occurred in the fracture surface. Therefore, the temperature was manifested by these phenomena to influence strongly on micro failure mechanism of sandstone. In addition, the failure mechanism would transit from brittle failure mechanism at low temperature to coupled brittle-ductile failure mechanism at high temperature. The variation of sandstone strength under differ- ent temperature can be attributed to the occurrence of plastic deformation, fatigue fracture, and microcracking. The fatigue striations in the fracture surfaces under high temperature may be interpreted as micro fold. And the coupled effect of tem- perature and tensile stress may be another formation mechanism of micro fold in geology.

关键词： sandstone, thermal-mechanical coupled effects, fractograph, plastic deformation, SEM, micro fold