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Depth Distribution of Moho Discontinuity Beneath beijing and Its Adjacent Area

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Earthquake Research in china 1998年第3期12卷 3-16页

作者： Ma Lin, Zheng Sihua, and Xue Fengcenter for analysis and {2., CSB, beijing 100036, china

Based on the method of "two-dimensional depth structure of the crust" proposed by Horiuchi et al., about 5000 arrival times of 303 local shallow earthquakes recorded by the beijing Seismographic Network from 1990 ~ 1993 are used to investigate the depth distribution of Moho discontinuity beneath beijing and its adjacent area. We simultaneously determined the hypo{2. parameters and P- and S-wave station corrections. The data of the North china Network were also investigated. The results are as follows: (1) The depth distribution of Moho discontinuity becomes shallower from the northwest to the southeast, i.e., in Zhangjiakou area, the Moho discontinuity is located at a depth range from 40~42.km. In the beijing area, it is 36~39 km. However, at the eastern and southeastern part of this area, it is only 2.-30 km and 30~32.km, respectively. (2. Beneath the Tangshan area, there is another elliptic interface shallower than the Moho discontinuity. Separately, its major and minor axis is approximately

关键词： Two-dimensional depth structure of the crust Moho discontinuity Station correction.

Physical analysis and numerical simulation for the dynamic behaviour of vehicles in pitching oscillations or rocking motions

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Science china(Technological Sciences) 2007年第4期50卷 385-401页

作者： ZHANG HanXin1,2.3, ZHANG Zhao1,3, YUAN XianXu1,2. LIU Wei1, XIE YuFei1,2.& YE YouDa1,2.1 china Aerodynamics Research and Development center, Mianyang 62.000, china 2.National Laboratory for Computational Fluid Dynamics, beijing University of Aeronautics and Astronautics, beijing 100083, china 3 School of Aerospace, Tsinghua University, beijing 100084, china china Aerodynamics Research and Development center School of Aerospace Tsinghua University National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and Astronautics

Analytical methods of nonlinear dynamics and numerical simulations for the cou-pling equations of Navier-Stokes and flight mechanics are used to study the dynamic behaviour of pitching motions of reentry capsules with the variation of Mach number, and rocking motions of swept wings with the variation of angle of attack. Conditions under which the dynamic instability, Hopf bifurcation and saddle-node bifurcation occur are obtained. The node-saddle-node topological structure in the phase portrait, i.e. the state of bi-attractors (attracting basins) is described. The evolving process of dynamic behaviour and flow fields are given. The theories are compared with some numerical simulations conducted by the authors. Besides, some verifiable experi-mental results are cited. The agreement between them is very well.

关键词： physical analysis numerical simulation pitching oscillation rocking motion bifurcation

The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2.4, ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3 1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 2. Department of Atmospheric Sciences, Yunnan University, Kunming 650091, china 3. china Meteorological Administration Training Centre, beijing 100081, china 4. Graduate School of Chinese Academy of Sciences, beijing 100039, china State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China china Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate prediction center’s merged {2. of pre- cipitation (CMAP) data and the National centers for Environmental prediction/National center for At- mospheric Research (NCEP/NCAR) re{2. dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum {2., band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South china Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2.d pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

Late Cenozoic Stratigraphic Sequence and Its Implication to Tectonic Evolution, Hejiakouzi Area, Ningxia Hui Autonomous Region

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Earthquake Research in china 2001年第4期15卷 380-389页

作者： Shen Xuhui, Tian Qinjian, Ding Guoyu, Wei Kaibo, and Chen Zhengweicenter for analysis and {2., china seismological bureau, beijing 100036, chinaChai Chizhangseismological bureau of Ningxia Hui Autonomous Region, Yinchuan 750001, china center for analysis and {2. China Seismological Bureau Beijing 100036 China seismological bureau of Ningxia Hui Autonomous Region Yinchuan 750001 China

The Late Cenozoic stratigraphic sequence and its information of tectonic evolution are obtained here through the detailed petrostratigraphic and magnetostratigraphic study and research of stratigraphic contact and sedmentary faces of the Cenozoic strata profile, Hejiakouzi area, Ningxia Hui Autonomous Region. The intense Cenozoic tectonic deformation began at 10Ma BP in the Haiyuan-Tongxin Syntaxis, the northeastern margin of Qinghai-Xizang Plateau, and a few deformation events occurred during Late Cenozoic Era.

关键词： Ningxia Hui Autonomous Region Hejiakouzi Cenozoic Magnetostratigraphy Tectonic event

The Natural Probability Distribution of Load and Unload Response Ratio

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Earthquake Research in china 1997年第1期11卷 43-49页

作者： Chen Qifu,Yin Xiangchu,and Ma Licenter for analysis and {2.,SSB,beijing 100036,china

In this paper,the Gutenberg-Richter model is used to generate seismic *** events that satisfy the random distribution are also *** those events,the natural probability distribution of Load and Unload Response Ratio(LURR),which measures quantitatively the degree of instability of a nonlinear system,is *** study is based on stress energy release,which is chosen as the response of nonlinear system *** comparative results from the observation catalogue and generating data are also *** is revealed that the natural probability of LURR is mostly stable when the sample number is *** lower the natural probability of LURR,the more the precursory is information it may *** influence of Y3 resulting from the sample number and the magnitude range of events is also discussed.

关键词： Natural Probability Distribution System Event load-unload response ratio.

Thermal Shock Property of Al/Ni-ZrO2.Gradient Thennal Barrier Coatings

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材料热处理学报 2004年第5期 974-976页

作者： FAN Jin-juan1, WANG Quan-sheng2. ZHANG Wei-fang1 1. Failure analysis center of {2. Institute of Aeronautical Materials, {2., china 2.Department of material science and engineering, {2. Institute of Technology, {2., china

Al/Ni-ZrO2.gradient thennal barrier coatings are made on aluminum substrate using plasma spraying method and one direction thermal shock properties of the coatings are studied in this paper. The results show that pores in coatings link to form cracks vertical to coating surface. They go through the whole ZrO2.coating once vertical cracks form. When thermal shock cycles increase, horizontal cracks that result in coatings failure forms in the coatings and interface. And vertical cracks delay appearance of horizontal cracks and enhance thermal shock property of coatings. Failure mechanisms of coating thermal shock are discussed using experiments and finite element method.

关键词： gradient thermal barrier coatings one direction shock finite element method

New evidence for lack of CMB power on large scales

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2.3 1 Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, beijing 100049, china 2.Department of Physics & {2. for Astrophysics, Tsinghua University, beijing 100084, china 3 Department of Engineering Physics & {2. for Astrophysics, Tsinghua University, beijing 100084, china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Department of Physics & center for Astrophysics Tsinghua University Department of Engineering Physics & center for Astrophysics Tsinghua University

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

Molecular Cloning of a Cytosolic G6PDH Gene from Populus Suaveolens and Its Expression to Improve the Cold Resistance of Tobacco Plants

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冰川冻土 2009年第6期31卷 1178-1185页

作者： LIN Yuan-zhen1,2.GUO Hai3,ZHANG Zhi-yi2.LIN Shan-zhi2.(1. College of Forestry,South china Agricultural University,Guangzhou Guangdong 510642.china 2. Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants,MOE,{2. Forestry University,{2. 100083,china 3. Plant Materials center for Soil and Water Conservation,Ministry of Water Resources,{2.100038,china) College of Forestry South China Agricultural University Guangdong Guangzhou 510642 Plant Materials center for Soil and Water Conservation Ministry of Water ResourcesChina Beijing 100038 beijing Forestry University Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental PlantsMOE Beijing 100083 beijing Forestry University Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental PlantsMOE Beijing 100083

Glucose-6-phosphate dehydrogenase (G6PDH,EC 1.***.1.49) is the first and main regulated enzyme of oxidative pentose phosphate pathway (OPPP),catalyzing the conversion of glucose-6-phosphate to 6-phospho-gluconolactone and playing important roles in the growth and development of plants. It is preciously reported that the enhancement of freezing resistance of Populus suaveolenscuttings is clear related to the distinct increase in cytosolic G6PDH activity. Here,a 1697 bp cDNA fragment (PsG6PDH) is amplified by RT-PCR from cold-induced total RNA of the freezing-tolerant P. suaveolens. A sequence analysis showed that PsG6PDH coding region had 1 530 bp and encoded 510 predicted amino acid residues. Genomic Southern analysis revealed that the isoform is encoded by a few copies of the gene in the poplar genome. The cloned gene PsG6PDHis cloned into binary vector pBI12. and used to transform tobacco. PCR and Southern blotting results verified integration of this gene into the genome of tobacco. Moreover,cold treatment experiments and membrane defense enzymeactivity analysis confirmed that overexpression of the PsG6PDHgene could enhance the tolerance to cold or frigid stresses in transgenic plants.

关键词： Populus suaveolens glucose-6-phosphate dehydrogenase cold resistance gene engineering

Pulmonary embolism and deep venous thrombosis in china

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Journal of Geriatric Cardiology 2024年第8期21卷 775-778页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina 不详

The Annual Report on Cardiovascular Health and Diseases in china(2.2.) intricate landscape of cardiovascular health in *** connection with the previous section,this eighth section of the report offers a comprehensive analysis of pulmonary embolism and deep venous *** recent years,research in the field of pulmonary vessel in china has made great progress.A number of nationwide multi-center registry research results have filled the gaps in the epidemiology,diagnosis and treatment of pulmonary hypertension and venous *** types of pulmonary hypertension still need attention to the identification of risk factors and/or risk stratification,and venous thromboembolism needs attention in the prevention and the overall management inside and outside *** the future,we look forward to the publication of more high-quality research in china,which could be able to improve relevant guidelines for pulmonary vascular diseases both domestically and inter-nationally.

关键词： epidemiology prevention diagnosis