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Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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Science china Earth Sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1, PENG Suping1, ZHANG Zhongjie2.& LIU Zhenkuan3 1. china University of Mining & Technology, beijing 100083, china 2. institute of Geophysics, Chinese Academy of Sciences, beijing 100101, china 3. Exploration and Development Research institute of Daqing Oilfield, Daqing 163712. china china University of Mining & Technology Beijing China institute of Geophysics Chinese Academy of Sciences Beijing China Exploration and Development Research institute of Daqing Oilfield Daqing China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.

Integrative inversion of land surface component temperature

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Science china Earth Sciences 2005年第11期48卷 2011-2019页

作者： FAN Wenjie1 & XU Xiru1,2.1. institute of Remote Sensing and Geographical Information System, Peking University, beijing 100871,{2. 2. Center of Remote Sensing and GIS of beijing Normal University, beijing 100875,{2. institute of Remote Sensing and Geographical Information System Peking University Beijing China Center of Remote Sensing and GIS of beijing Normal University Beijing China

In this paper, the row winter wheat was selected as the example to study the com-ponent temperature inversion method of land surface target in detail. The result showed that the structural pattern of row crop can affect the inversion precision of component temperature evi-dently. Choosing appropriate structural pattern of row crop can improve the inversion precision significantly. The iterative method combining inverse matrix was a stable method that was fit for inversing component temperature of land surface target. The result of simulation and field ex-periment showed that the integrative method could remarkably improve the inversion accuracy of the lighted soil surface temperature and the top layer canopy temperature, and enhance inver-sion stability of components temperature. Just two parameters were sufficient for accurate at-mospheric correction of multi-angle and multi-spectral thermal infrared data: atmospheric trans-mittance and the atmospheric upwelling radiance. If the atmospheric parameters and component temperature can be inversed synchronously, the really and truly accurate atmospheric correction can be achieved. The validation using ATSRII data showed that the method was useful.

关键词： components temperature, inverse pattern, atmospheric correction

Heavy ion reactions around the Coulomb barrier

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2. ZHANG GaoLong1,3, YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 china institute of {2. energy, P. O. Box 2.5(10), beijing 1.241., china 2.Particle Astrophysics Center, institute of High energy Physics, Chinese Academy of Sciences, beijing 100039, china 3 School of Physics and Nuclear energy Engineering, Beihang University, beijing 100191, china china institute of {2. energy Beijing China Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of Physics and Nuclear energy Engineering Beihang University Beijing China

The angular distributions of fission fragments for the 32.+184W reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 32.+90,96Zr in an energy range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 32.+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+2.8Pb, 196Pt, 184W, and 154,152.m at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12. at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 2.% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

Wave tectono-sedimentary processes in Tarim basin

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Science china Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1,2. ZHANG Yiwei1 & CHEN Shuping1 1. Key Laboratory for Hydrocarbon Accumulation, Ministry of Education, china University of Petroleum, beijing 102.49, china 2. Exploration and Production Research institute, china Petroleum & Chemical Corporation, beijing 100083, china Key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum Beijing China Exploration and Production Research institute China Petroleum & Chemical Corporation Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 2.0±Ma, 100±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 2.0±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2. , XIANG Jianhai 1*, WANG Bing 1,2. , LI Fuhua 1 and TONG Wei 3(1. Experimental Marine Biology Laboratory, institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071,china 2. Graduate School of the Chinese Academy of Sciences, {2. 100039, china 3. Genomics & Bioinformatics institute, Chinese Academy of Sciences, {2. 101300, china) Chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

Designing appropriate heat treatment temperature for LaNi_(3.8)Al_(0.75)Mn_(0.45) alloy

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Rare Metals 2006年第Z1期25卷 243-246页

作者： JIANG Yuwei LIU Xiaopeng JIANG Lijun WANG Shumao YANG Hongguang institute for energy Material and Technology General Research Institute for Non-Ferrous MetalBeijing 100088China china institute of {2. energy Beijing 102413China

The effect of heat treatment on microstructure,equilibrium hydrogen sorption pressure and plateau slope of LaNi_(3.8)Al_(0.75)Mn_(0.45) alloy was investigated.X-ray diffraction(XRD)analysis indicates that annealed alloys have single phase and the same hexagonal structure as that of LaNi_(5) alloy(CaCu_(5) type,P6/mmm).The cell parameters of alloys fluctuate with the increasing annealing *** equilibrium hydrogen pressure and plateau slope are a parabola function with annealing temperature for LaNi_(3.8)Al_(0.75)Mn_(0.45) *** this relationship,an appropriate heat treatment temperature for LaNi_(3.8)Al_(0.75)Mn_(0.45) alloy is determined to about 12.0-12.0 K by mathematic simulation ***,the maximum hydrogen storage capacity of alloys does not affected by the annealing temperature.

关键词： La-Ni-Al alloy heat treatment hydrogen storage alloy plateau slope

Plus cupping degrees do not form an ideal

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Science in china(Series F) 2004年第5期47卷 635-654页

作者： LI Angsheng1,2.& ZHAO Yicheng1 1. institute of Software,Chinese Academy of Sciences,beijing 100080,{2. 2. School of Information Sciences,beijing Normal University,beijing 100871,{2. institute of Software Chinese Academy of Sciences Beijing China School of Information Sciences Beijing Normal University Beijing China

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0 详细信息

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0

关键词： computably enumerable set Turing degree definability.

Effect of Manganese substitution on hydrogen storage properties of LaNi_(4.2.-x)Al_(0.75)Mn_(x) alloy

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Rare Metals 2006年第Z2期25卷 204-208页

作者： JIANG Yuwei LIU Xiaopeng JIANG Lijun WANG Shumao YANG Hongguang institute for energy Materials and Technology General Research Institute for Non-ferrous MetalsBeijing 100088China china institute of {2. energy Beijing 102413China

The effect of Mn substitution on phase structure,hydrogen hydriding/dehydriding properties(plateau pressure and slope)and reaction heat enthalpy of LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloys(x=0,0.2.,0.35,0.45,0.55 and 0.65)were *** experimental results show that all LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloys have single phase and have the same hexagonal structure as that of LaNi5 alloy(CaCu_(5)type,P6/mmm).With increasing Mn substitution content,the cell parameters of LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloy greatly increase,but the maximum hydrogen storage capacity and the equilibrium absorption pressure of LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloy decrease from 1.38 wt.%to 1.18 wt.%and from 1.61 to 0.0712.MPa,***,the hydrogen pressure plateau slope factorσincreases from 0.014 to 0.18,but the hysteresis factor is nearly *** heat enthalpy absolute value|ΔH_(plat)|increases from 46.7 kJ·mol^(-1)H2.to 56.1 kJ·mol^(-1)H_(2.as the Mn content x increases from 0 to 0.65.

关键词： hydrogen storage alloy La-Ni-Al-Mn alloy P-C-T hysteresis and plateau slope

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, {2. 100085, china 2.Department of Geophysics, Peking University, {2. 100871, china institute of Crustal Dynamics China Earthquake Administration Beijing China Department of Geophysics Peking University Beijing 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 4.2.102. Pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 44.6% in 450 days after the Chi-Chi earthquake, with 34.7% caused by the viscous relaxation and 2..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