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Dynamic mechanisms of the post-seismic deformation following large events:Case study of the 1999 Chi-Chi earthquake in Taiwan of china

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Science china Earth Sciences 2009年第11期52卷 1813-1824页

作者： ZHU ShouBiao1,2 & CAI YongEn2 1 Institute of Crustal Dynamics, china Earthquake Administration, beijing 100085, china 2 department of Geophysics,{4., beijing 100871, china 1. Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China 2. department of Geophysics Peking University Beijing 100871 China

The mechanism of postseismic deformation related to strong earthquakes is important in geodynamics, and presumably afterslip or viscoelastic relaxation is responsible for the postsesimic deformation. The 1999 Chi-Chi, Taiwan of china, earthquake occurred in the region where GPS observation station is most densely deployed in the world. The unprecedented GPS data provides a unique opportunity to study the physical processes of postseismic deformation. Here we assume that the interactions of viscoelastic relaxation, afterslip, fault zone collapse, poroelastic rebound, flow of underground fluids, and all these combined contribute to the surface displacements following the main shock. In order to know the essence of the postseismic deformation after the strong event, fault zone collapse, poroelastic rebound, flow of underground fluids, and so on, are represented equivalently by the variations of the focal medium properties. Therefore, the viscoelastic relaxation, afterslip, and the variations of the equivalent focal medium properties are inverted by applying the GPS temporal series measurement data with viscoelastic finite element method. Both the afterslip rate distribution along the fault and the afterslip evolution with time are obtained by means of inversion. Also, the preliminary result suggests that viscosities of the lower crust and the upper mantle in Taiwan region is 2.7×1018 and 4.2×1020 Pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 4..6% in 4.0 days after the Chi-Chi earthquake, with 34.7% caused by the viscous relaxation and 20.7% by other factors such as fault zone collapse, poroelastic rebound, and the flow of liquids.

关键词： mechanism of postseismic deformation viscoelastic finite element method GPS temporal series data Chi-Chi earthquake

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A submillimeter observation and study of star-forming regions

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Chinese Science Bulletin 2002年第1期47卷 16-21页

作者： JIANG Linhua, WU Yuefang & M. Millerdepartment of Astronomy, peking university, beijing 100871, china Chinese Academy of Sciences-{4. university Joint beijing Astrophysics Center, beijing 100871, china I. Physikalisches Institut, Zulpicher Str department of Astronomy Peking University Beijing China Chinese Academy of Sciences-peking university Joint beijing Astrophysics Center Beijing China I. Physikalisches Institut Koeln 41 Germany

Using the 3-m radio telescope of KOSMA, we mapped 12CO (J = 3-2) lines for three molecular clouds, B35, S14. and TMC-2A. High-velocity molecular outflows are found in all these regions. The physical and dynamical pa-rameters of the outflows are derived, and their shapes and driving sources are analyzed. Contour maps of center veloci-ties show that the large scale systematic gradients exist in the three clouds. These observed motions are best explained by rotation after excluding the cause of outflows. Furthermore, in the core region of TMC-2A there is a velocity gradient in opposite direction from that of the large scale. It may be caused by magnetic braking. Finally, angular velocities of the clouds are calculated, and the effects of rotation against gravity and lowering the star-formation rate are also ana-lyzed.

关键词： dynamics of interstellar medium jets and outflows star formation.

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Landscape ecology：the theoretical foundation of sustainable agrolandscape planning and design

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Journal of Environmental Sciences 1995年第3期7卷 289-296页

作者： Wang Yanglin(department of Geography, peking university, beijing 100871 , china)Fu Bojie(Research Center for Eco-Environrnental Sceiences, Chinese Acaderny of Sciences, {4. 100085, china)

Ｌａｎｄｓｃａｐｅｅｃｏｌｏｇｙ：ｔｈｅｔｈｅｏｒｅｔｉｃａｌｆｏｕｎｄａｔｉｏｎｏｆｓｕｓｔａｉｎａｂｌｅａｇｒｏｌａｎｄｓｃａｐｅｐｌａｎｎｉｎｇａｎｄｄｅｓｉｇｎ．ＷａｎｇＹａｎｇｌｉｎ（Ｄｅｐａｒｔｍｅｎｔｏ... 详细信息

Ｌａｎｄｓｃａｐｅｅｃｏｌｏｇｙ：ｔｈｅｔｈｅｏｒｅｔｉｃａｌｆｏｕｎｄａｔｉｏｎｏｆｓｕｓｔａｉｎａｂｌｅａｇｒｏｌａｎｄｓｃａｐｅｐｌａｎｎｉｎｇａｎｄｄｅｓｉｇｎ．ＷａｎｇＹａｎｇｌｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＧｅｏｇｒａｐｈｙ，Ｐｅｋｉｎｇ...

关键词： landscape ecology sustainable development agrolandscape sustainabillty.

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SURFACE-ENHANCED CANTILEVER SENSORS WITH NANO-POROUS FILMS

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Acta Mechanica Solida Sinica 2010年第1期23卷 1-12页

作者： Huiling Duan(State Key Laboratory for Turbulence and Complex System,CAPT and department of Mechanics and Aerospace Engineering,College of Engineering,peking university,beijing {4.,china) [a] State Key Laboratory for Turbulence Complex System CAPT department of Mechanics Aerospace Engineering College of Engineering Peking University Beijing 100871 China

Developing surface-enhanced microcantilevers with improved sensitivities is of longstanding interest. In this paper, the design of surface-enhanced cantilever sensors using nano- （micro-） porous films as surface layers is proposed. The static deformation and resonance frequencies of these surface-enhanced sensors with the simultaneous effects of the eigenstrain, the surface stress and the adsorption mass are analyzed. It is shown that the sensitivities of these novel cantilever sensors for the static deformation and resonance frequencies can be tuned by the porosity, the size of the pores and the structure of the porous films. For the three kinds of cantilever consisting of solid films, films with aligned cylindrical micro-scale pores, and those with nano-scale pores, the nano-porous one has the highest static and dynamic sensitivities, whereas the solid one has the lowest.

关键词： cantilever sensors nano- (micro-) porous films surface stress curvature resonance frequency

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Effects of diffusion time and diffusion gradient strength on the mean diffusivity of water molecules in healthy human brain

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Progress in Natural Science:Materials International 2006年第7期16卷 706-711页

作者： GAO Song, WANG Xiaoying and BAO Shanglian ( Laboratory of Medical Physics & Engineering, peking university, beijing 100871, china department of Radiology, The First Affiliated Hospital of peking university, beijing 100034. china) peking Univ Lab Med Phys & Engn Beijing 100871 Peoples R China peking Univ Affiliated Hosp 1 Dept Radiol Beijing 100034 Peoples R China

Diffusion time and diffusion gradient strength are two important parameters of pulsed gradient spin echo (PGSE) that is the most commonly used method in diffusion-weighted magnetic resonance imaging. However, the effects of the diffusion time on the mean diffusivity (MD) in previous studies are controversial. In this study, a new experimental protocol was designed to evaluate the effects of the two parameters on the results of PGSE. It was found that MD decreased significantly with the increased diffusion time or increased diffusion gradient strength, which cannot be explained by the previous theories. Through theoretical analysis, we found the flaw in the pulsed gradient spin echo (PGSE) method, which is the explanation for the controversial results of diffusion time obtained by oth- ers.

关键词： diffusion time diffusion gradient strength diffusion-weighted imaging diffusion tensor imaging mean diffusivity.

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Steady motion and spiral patterns in typhoon

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Acta Oceanologica Sinica 1999年第4期18卷 495-504页

作者： Liu Shikuo Liang Fuming Liu Shida and Xin Guojun (department of Geophysics, peking university, beijing 100871, china) department of Geophysics Peking University Beijing 100871 China

By using the equations describing typhoons in the atmosphere, the steady three-dimensional stream fieldand the corresponding pressure and temperature fields are obtained. The three-dimensional velocity fields construct anonlinear autonomuos system in the physical space. It is shown that the center of typhoon is a local minimum pressurewith positive vertical vorticity and horizontal convergence in lower levels and a local maximum pressure with negativevertical vorticity and horizontal divergence in the upper levels. Because there exits two saddle-focus points in the autnomous system, there exist the spiral patterns, in which the winds blow spirally in and out of the center in the lowerand upper levels in the Northern Hemisphere and cause the ascending motion near the center and dascending motionnear the edge, respectively . All these are in fair conformity with the observations. It implies that the rotation of earthand the viscosity of air play an important role in the spiral structure of typhoons.

关键词： Typhoon steady motion spiral pattern

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Enantioselective Addition of Diethylzinc to Benzaldehyde by Catalysts of Chiral Heterocyclic Ligands

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Chinese Chemical Letters 1999年第9期10卷 717-718页

作者： Yan HE Yue Lan LI Ye Di GUAN(department of Chemistry, peking university, beijing 100871) peking Univ Dept Chem Beijing 100871 Peoples R China

Several kinds of chiral heterocyclic ligands without hydroxyl group have been synthesized and used as catalysts for the asymmetric addition of diethylzinc to benzaldehyde. These ligands promoted the formation of (S)-1... 详细信息

关键词： chiral heterocyclic ligands hydroxyl group asymmetric catalysis enantioselectivity

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Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science china Chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3, ZHAO Ying2, LING Xiaofeng3, LI Qingbo1, WANG Jiansheng4. ZHANG Nengwei3, ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, College of Chemistry and Molecular Engineering, peking university, beijing 100871, china 2. Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 3. department of Surgery, Third Hospital, peking university, beijing 100083, china 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) 1. The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 2. department of Surgery Third Hospital Peking University 100083 Beijing China 3. Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 4. department of Oncology Surgery the First Hospital of Xi’an Jiaotong University 710061 Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 4. patients, including 32 normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 154. cm-1, a shift of the amide I band to lower wave number, a decrease in the ～14.0 cm-1 peak to less than the～14.0 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

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Circadian expression of clock genes and angiotensin Ⅱ type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

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Acta Pharmacologica Sinica 2007年第4期28卷 484-492页

作者： Hui LI~2,Nmg-ling SUN~(2,4.,Jin WANG~3,Ai-jun LIU~3,Ding-feng SU~(3,4.~2department of Cardiology,peking university People's Hospital,beijing 10004.,{4. ~3department of Pharmacology,Second MilitaryMedical university,Shanghai 2004.3,{4. department of Cardiology Peking University People's Hospital Beijing China department of Pharmacology Second Military Medical University Shanghai China

Aim:To investigate whether the circadian expression of central clock genes andangiotensin Ⅱ type 1 (AT1) receptors was altered in sinoaortic-denervated (SAD)***:Male Sprague-Dawley rats underwent sinoaortic denervation or asham operation at the age of 12 *** weeks after the operation,bloodpressure and heart period were measured in the conscious state in a group ofsham-operated (n=10) and SAD rats (n=9).Rest SAD and sham-operated ratswere divided into 6 groups (n=6 in each group).The suprachiasmatic nuclei (SCN)tissues were taken every 4.h throughout the day from each group for the determi-nation of the mRNA expression of clock genes (Per2 and Bmal1) and the AT1receptor by RT-PCR;the protein expression of Per2 and Bmal1 was determined byWestern ***:Blood pressure levels in the SAD rats were similar tothose of the sham-operated ***,blood pressure variabilities signifi-cantly increased in the SAD rats compared with the sham-operated *** variation of clock genes in the SCN of the sham-operated rats was char-acterized by a marked increase in the mRNA and protein expression during ***2 and Bmal1 mRNA levels were significantly lower in the SAD rats,especially during dark *** blot analysis confirmed an attenuation ofthe circadian rhythm of the 2 clock proteins in the SCN of the SAD ***1receptor mRNA expressions in the SCN were abnormally upregulated in the lightphase,changed to a 12-h cycle in the SAD ***:The circadian varia-tion of the 2 central clock genes was attenuated in the SAD *** baroreflexdysfunction also induced a disturbance in the expression of AT1 receptors in theSCN.

关键词： circadian rhythm arterial baroreflex clock genes sinoaortic denervation reninangiotensin system

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Deprotection of t-Butyldimethylsiloxy (TBDMS) Protecting Group with Catalytic Copper (II) Chloride Dihydrate

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Chinese Chemical Letters 2000年第9期11卷 753-756页

作者： Zhong Ping TAN Lin WANG Jian Bo WANG department of Chemistry, peking university, beijing 100871 peking Univ Dept Chem Beijing 100871 Peoples R China

t-Butyldimethylsilyl (TBDMS) ether can be cleaved upon refluxing in acetone/H2O (95 : 5) in the presence of a catalytic amount of copper (II) chloride dihydrate (5 mmol %).

关键词： TBDMS ether deprotection copper (II) chloride dihydrate

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