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Science china Earth sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1,2. YAO Tandong2.1, PU Jianchen1, ZHANG Yongliang1 & SUN Weizhen1 1. key laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering Research Institute, {2., Lanzhou 730000, china 2. Institute of Tibetan Plateau Research, {2., beijing 100085, china 1. key laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 112.A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 18O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 2.th-century warming was within the range of natural climate variability, and the warmest century was the 17th century while the warmest decade was the 1610s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 19th century. Comparing the variations of δ 18O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 101―102.years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.

Scan chain design for shift power reduction in scan-based testing

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Science china(Information sciences) 2011年第4期54卷 767-777页

作者： LI Jia 1,HU Yu 2.& LI XiaoWei 2.1 The School of Software,Tsinghua University,beijing 100084,china 2.The Institute of Computing Technology,{2.,beijing 100190,china 1. The School of Software Tsinghua University Beijing 100084 China2. The Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Test power of VLSI systems has become a challenging issue *** scan shift power dominates the average test power and restricts clock frequency of the shift phase,leading to excessive thermal accumulation and long test *** paper proposes a scan chain design technique to solve the above *** on weighted transition metric (WTM),the proposed extended WTM (EWTM) that is utilized to guide the scan chain design algorithm can estimate the scan shift power in both the shift-in and shift-out ***,the wire length overhead of the proposed scan chain design can also be reduced by the proposed distance of EWTM (DEWTM) *** results confirm that the proposed approach can significantly reduce scan shift power with low wire length overhead.

关键词： low power DfT scan-based testing test power reduction scan chain design

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2.3 1. National Marine Environmental Forecasting Center, beijing 100081, china 2. {2. laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., china 3. Graduate University of chinese academy of sciences, beijing 100049, china 1. National Marine Environmental Forecasting Center Beijing 100081 China 2. key laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Graduate University of chinese academy of sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Experimental demonstration of a new concept of drag reduction and thermal protection for hypersonic vehicles

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Acta Mechanica Sinica 2009年第3期25卷 417-419页

作者： Zonglin Jiang Yunfeng Liu Guilai Han Wei Zhao key laboratory of High Temperature Gas Dynamics, Institute of Mechanics, {2., 100190 beijing, china key laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100190 Beijing China

A new idea of drag reduction and thermal protection for hypersonic vehicles is proposed based on the combination of a physical spike and lateral jets for shockreconstruction. The spike recasts the bow shock in front of a blunt body into a conical shock, and the lateral jets work to protect the spike tip from overheating and to push the conical shock away from the blunt body when a pitching angle exists during flight. Experiments are conducted in a hypersonic wind tunnel at a nominal Mach number of 6. It is demonstrated that the shock/shock interaction on the blunt body is avoided due to injection and the peak pressure at the reattachment point is reduced by 70% under a 4° attack angle.

关键词： Hypersonic vehicle Shock-reconstruction. Drag reduction Thermal protection Spike and lateral jets

Synthesis of well-defined functional PE graft copoly-mers via ATRP process

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Science Bulletin 2005年第10期50卷 1048-1051页

作者： CAO Chengang1, 2. DONG Jinyong1 & HU Youliang1 1. CAS key laboratory of Engineering Plastics, Joint laboratory of Polymer Science and Materials, Institute of Chemistry, chinese academy of sciences, beijing 100080, china 2. Graduate School, chinese academy of sciences, beijing 100039, china CAS key laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China

In summary, we have demonstrated a convenient yet highly efficient method forthe preparation of PE-based graft copolymers via ATRP.. By introducing a small amount of styrenegroups into PE chains via the selective copolymerization of ethylene with 1,4-divinylbenzenecatalyzed by Et(Ind)_2.rCl_2.MAO, the multifunctional ATRP initiator of1-chloroethylbenzene-containing PE was readily achieved by a quantitative hydrochlorination reactionand was shown to be very effective for the initiation of graft polymerization of MMA and styrene toprepare structurally well-defined PE-based graft copolymers.

关键词： ATRP Synthesis of well-defined functional PE graft copoly-mers via ATRP process PE well

Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural Science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1** and CHEN Wende2.1. School of Mathematical sciences, Peking University, beijing 100871, {2. 2. laboratory of Systems and Control and key State laboratory of Information Security, Institute of Systems Science, academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, {2.) School of Mathematical sciences Peking University Beijing 100871 China. laboratory of Systems and Control and key State laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

The biomarkers of 2.6,10,15, 19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

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chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2.& WANG Cuiping1,31. State key laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, {2., Guangzhou 510640, china 2. Guangzhou Research Center of Gas Hydrate, {2., Guangzhou 510640, china 3. Graduate School of {2., beijing 100039, china State key laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangzhou Research Center of Gas Hydrate Chinese Academy of Sciences Guangzhou 510640 China Graduate School of chinese academy of sciences Beijing 100039 China

A group of 2.6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 2.8 *** PMIΔ compounds are distributed between nC2. and nC2. on the mass chromatogram of aliphatic fraction. Their δ 13C values are very much depleted in 13C and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13C values of companion n-alkanes range from ?2..4‰ to ?34.6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物

Cloning and expression of putative ethylene receptor genes in soybean plant

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Progress in Natural Science:Materials International 2007年第10期17卷 1152-1160页

作者： Xie Zongming1,2.3, Lei Gang1,2. Wuriyanghan Hada1,2. Tian Aiguo1, Zhang Jinsong1 and Chen Shouyi1(1. National key laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, {2., beijing 100101, china 2. Graduate School of {2., beijing 100039, china 3. Xinjiang academy of Agricultural and Reclamation Science, Shihezi 832.00, china) National key laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China Graduate School of chinese academy of sciences Beijing 100039 China Xinjiang academy of Agricultural and Reclamation Science Shihezi 832000 China

Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1, GmERS1, GmETR2.and GmEIN4. Construction of the phylogenic tree showed that GmETR1 and GmERS1 belong to subfamily I whereas GmETR2.and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed.

关键词： abiotic stress expression analysis ethylene receptor plant hormone soybean.

Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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Science china Earth sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3,YAN JingHua1 & HU HaiBo2.1 Institute of Tropical and Marine Meteorology,chinese Meteorological Administration(CMA),Guangzhou 510080,china 2.Institute of Urban Meteorology,CMA,{2. 100089,china 3 State key laboratory of Severe weather,chinese academy of Meteorological sciences,{2. 100081,china 1. Institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. State key laboratory of Severe {2. Chinese Academy of Meteorological Sciences Beijing 100081 China 2. Institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from Guangzhou mesonet Automatic weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2.and Luo Zhexian2.1. Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., {2. 2. Nanjing University of Information sciences & Technology, Nanjing 2.0044, {2.) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of Information sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 12.0 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation