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What Are You Going to Conquer with the Spear?

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genomics,Proteomics & Bioinformatics 2005年第1期 9-10页

作者： Jun Yu beijing genomics institute, Chinese Academy of Sciences, beijing 101300, China. beijing genomics institute Chinese Academy of Sciences Beijing 101300 China

Almost everyone in China knows this story, even elementary school pupils: Once upon a time, there was a weapon salesman claiming with confidence to one crowd that all his spears were capable of piercing every shield that existed in the world, then he turned around and told the other crowd mysteriously that all his shields were not penetrable. A bystander who heard both claims asked him, How about stabbing your shields with your spears? It was indeed an unexpected question that made the eloquent salesman mute right on the spot. Since then, the Chinese people have called contradiction as mao-dun, which literally means the spear (pronounced as mao) and shield (pronounced as dun).

关键词： What Are You Going to Conquer with the Spear Nature gene

Canonical correlation analysis to land-use structure and its driving forces——Taking Yulin Prefecture as an example

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Journal of Geographical Sciences 1998年第2期8卷 73-79页

作者： ZHANG Minginstitute of Geography, cas, beijing 100101 CHINA

In this paper, one of the most classical statistical methods, Canonical Correlation Analysis (CCA) is applied to identify quantitatively the driving forces of landuse structure in Yulin Prefecture. The main analysis is carried out through the software SPSS with the data on the level of towns and townships in 1992. The results indicate that landuse structure is determined by comprehensive action of different factors. Landuse structure with rural characteristics is mainly determined by geographical factors such as the elevation, temperature and precipitation, while the landuse structure with urban characteristics is mainly determined by demographic and socioeconomic conditions. At the same time, tests were carried out through the canonical correlation coefficient and redundancy analysis.

关键词： Canonical Correlation Analysis Redundancy Analysis landuse and landcover change driving force

Construction of Optimal Truncated Low-Dimensional Dynamical systems directly from PDEs

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Communications in Nonlinear Science and Numerical Simulation 1998年第1期3卷 1-5页

作者： Hongliang ZHAO, Chuijie WU(LNM, institute of Mechanics, cas, beijing, 100080) (Air Force institute of Meteorology, Nanjing, 211101) Email: cjwu@*** LNM Institute of Mechanics CAS Beijing 100080 China Air Force institute of Meteorology Nanjing 211101 China

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关键词： low dimensional dynamical system partial differential equations optimization

Soil erosion and management on the Loess Plateau

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Journal of Geographical Sciences 2001年第1期11卷 53-70页

作者： CAI Qiang-guo (institute of Geographic Sciences and Natural Resources Research, cas, beijing 100101, China) institute of Geographic Sciences and Natural Resources Research CAS Beijing China

The Loess Plateau is well known to the world for its intense soil erosion. The root cause for river sedimentation of Yellow River (Huanghe) and its resultant “hanging river” in certain section is soil and water loss on the Loess Plateau. The Loess Plateau has a long cultivation history, hence population growth, vegetation degeneration and plugging constitute the chief reason for serious soil and water loss on Loess Plateau. This paper analyses several successful cases and failures in soil conservation, presents practical soil conservation technique and related benefit analysis, and discusses some effective methods adopted in China in soil erosion control, research directions and future perspectives on Loess Plateau.

关键词： soil erosion control technique management Loess Plateau

Geochemical Characteristics and Tectonic Setting of the Laohushan Basalts, North Qilian Mountains

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 452-457页

作者： QIAN Qing and ZHANG Qi institute of Geology and Geophysics, cas, P. O. Box 9825, beijing 100029 institute of Geology and Geophysics CAS P. O. Box 9825 Beijing 100029 [?]2Qian Qing Born in 1969 graduated from the Peking University in 1992 obtained the master's degree in 1996 and doctor's degree in 1999 now an associated research professor in the institute of Geology and Geophysics Chinese Academy of Sciences (CAS) mainly engaged in petrological and geochemical studies of volcanic rocks. Tel: 010–62008085 E-mail: qq613@kimo.com.tw or zhangqi@***.

The Ordovician Laohushan ophiolite, located in the eastern part of the North Qilian Mountains, is mainly composed of meta-peridotites, gabbros and basalts alternating with sediments. The sediments are mainly turbidites, including sandstones, siltstones, cherts etc. Major elements show that the basalts are subalkaline tholeiites and may be analogous to ocean-floor basalts. Except a few N-MORBs, most of the basalts are E-MORBs as indicated by incompatible element ratios such as (La/Ce)N, La/Sm, Ce/Zr, Zr/Y and Zr/Nb. Negative Nb anomaly is common but negative Zr, Hf and Ti anomalies are quite rare. Based on the geochemical characteristics, it is suggested that the Laohushan basalts were formed in a back-arc basin. ENd (t) of the basalts ranges between +3.0 and +8.9 and (87Sr/86Sr), ranges between 0.7030 and 0.7060, indicating a depleted mantle source which was mixed with more or less enriched mantle components. Furthermore, the petrography of the sandstones and geochemistry of the cherts suggest that the sediments were deposited near a continental margin.

关键词： North Qilian Mountains Laohushan basalts sediments geochemistry

Detonation initiation developing from the Richtmyer-Meshkov instability

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Acta Mechanica Sinica 2007年第4期23卷 343-349页

作者： H.H.Teng Z.L.Jiang Z.M.Hu LHD.institute of Mechanics,cas.beijing 100080,China LHD Institute of Mechanics CAS Beijing 100080 China

Detonation initiation resulting from the Richtmyer-Meshkov instability is investigated numerically in the configuration of the shock/spark-induced-deflagration interaction in a combustive gas mixture. Two-dimensional multi-species Navier-Stokes equations implemented with the detailed chemical reaction model are solved with the dispersion-controlled dissipative scheme. Numerical results show that the spark can create a blast wave and ignite deflagrations. Then, the deflagration waves are enhanced due to the Richtmyer-Meshkov instability, which provides detonation initiations with local environment conditions. By examining the deflagration fronts, two kinds of the initiation mechanisms are identified. One is referred to as the deflagration front acceleration with the help of the weak shock wave, occurring on the convex surfaces, and the other is the hot spot explosion deriving from the deflagration front focusing, occurring on the concave surfaces.

关键词： Hot spot Deflagration front acceleration Detonation initiation Richtmyer-Meshkov instability

Overview of HBV whole genome data in public repositories and the Chinese HBV reference sequences

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Progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo Ding c, Changqing Zeng b,* a Graduate School of Chinese Academy of Sciences, beijing 100049, China b beijing institute of genomics, Chinese Academy of Sciences, beijing 101300, China c beijing Youan Hospital, Capital Medical University, beijing 100069, China Graduate School of Chinese Academy of Sciences Beijing 100049 China beijing institute of genomics Chinese Academy of Sciences Beijing 101300 China beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis B virus (HBV) whole genomic sequences in public nucleotide databases (GenBank, EMBL, and DDBJ) had reached 866 by January 1, 2007. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HBV, we here present an overview of HBV sequences in public databases. From all registered 229 HBV genomes in Chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HBV strains prevailing in China. These analyses provide clues for the effects of HBV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HBV mutations. Based on the analysis of various public databases, we suggest that the Chinese HBV database with the clinical information should be constructed.

关键词： Public databases HBV genomic sequences Genotype Subtype Chinese reference sequences

THE RISK ASSESSMENT OF THE LONG-DISTANCE OILPIPELINE ENGINEERING

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Journal of Geographical Sciences 1996年第1期6卷 78-83页

作者： Wang Jinghua Mu Congru(institute of Geography, cas, beijing 100101People’s Republic of China) institute of Geography CAS Beijing 100101 China

The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development of oil industry , The risk assessment of oil industry has many subjects worthy to be *** major purpose of the paper is to research the risk cases of long-distance oil pipeline engineering in Ganshu and Shaanxi provinces.

关键词： long-distance oil pipeline risk assessment engineering Gansu Shaanxi

REGIONAL DIFFERENTIATION OF CRITICAL CONCENTRATION OF ARSENIC(As) AND CADMIUM (Cd) IN MAIN SOIL TYPES OF CHINA

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Journal of Geographical Sciences 1996年第2期6卷 60-65页

作者： Luo Jinfa Xia Zenglu(institute of Geography, cas, beijing 100101People’s Republic of China ) Inst of Geography CAS Beijing 100101 China

Studies of critical concentration distribution features of polluted elements of Cd and As in main soil types of China, such as laterite, crimson soil, purplish soil, yellow brown soil, brunisolic soil, black soil, cinnamon soil and sierozem revealed that soil types vary in different zones, so do their critical *** critical concentration has a zonal differentiation with the distribution of soil types from south to north, and from east to west. The critical concentration of Cd increases from south to north (yellow brown soil,brunisolic soil and cinnamon soil),and from east to west (black soil and sierozem). This coincides With changes of climate zones and soil zones. On the contrary, the critical concentration of Asdecreases from south to north and from east to west.

关键词： soil types critical level As Cd regional differentiation