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Sea surface temperature east of Australia:A predictor of tropical cyclone frequency over the western North Pacific?

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Chinese Science Bulletin 2011年第2期56卷 196-201页

作者： ZHOU BoTao 1,2.& CUI Xuan 3 1 National climate Center,China meteorological Administration,Beijing 100081,China 2.Nansen-Zhu International Research Center,institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 10002.,China 3 National meteorological Center,China meteorological Administration,Beijing 100081,China National climate Center China Meteorological Administration Beijing China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China National meteorological Center China Meteorological Administration Beijing China

The relationship between sea surface temperature (SST) east of Australia and tropical cyclone frequency over the western North Pacific (WNPTCF) is analyzed by use of observation *** WNPTCF from June to October is correlated negatively to spring SST east of *** the spring SST is in the positive phase,a cyclonic circulation anomaly in the upper troposphere and an anticyclonic circulation anomaly in the lower troposphere prevail over the western North Pacific from June to October,concurrent with an anomalous atmospheric subsidence and an enlarged vertical zonal wind *** conditions are unfavorable for tropical cyclone genesis,and thus WNPTCF *** negative phase of the spring SST east of Australia leads to more tropical cyclones over the western North *** spring SST east of Australia may give rise to simultaneous change in tropical atmospheric circulation via the teleconnection wave train,and then subsequently affect atmospheric circulation variation over the western North Pacific.

关键词：热带气旋北太平洋澳大利亚西部海面温度热带大气环流预测频率

CSCO_3 CYCLES IN SALAWUSU RIVER BASINSINCE 150KA B.P.

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Chinese Geographical Science 2001年第4期11卷 50-56页

作者： LUO Kai-li1,2. LI Bao-sheng1,2. ZHU Yi-zhi2. JIN He-ling3, ZHANG David Dian4, YAN Man-cun5, LI Hou-xin1, YAO Chun-xia1, ZHANG Yu-hong1f 1. Department of Geography, South China Normal University, Guangzhou 510631, P. R. China 2. State Key Labor

ABSTRACT: This paper, with Milanggouwan stratigraphic section as a typical section of the Salawusu River Basin, explores the relation between CaCO3 content distribution and climate change since 150 ka B. P. and concludes that: 1) The low-high changes of CaCO3 content in the section has a remarkable corresponding relation with the sedimentary cycles of ancient aeolian sand and overlying fluviolacustrine facies or palaeosols. 2. CaCO3 distribution in aeolian sand is relatively meagre, ranging from 0. 8% - 7. 18%, or on an average 2. 50% but relatively enriches in the fluviolacustrine faceis and palaeosols, ranging from 2. 2.% - 14. 9% , or on an average 5. 74%. This implies that they have different climatic backgrounds. The former was the product of erosion, transport and deposition by wind under arid and cold climatic conditions, whereas the latter was related to its special low-lying geomorphic position between the Ordos Plateau and Loess Plateau and warm-humid climatic environment. When the climatic became warm and humid, fluviolacustrine and swamp facies developed, soil-forming action strengthened, and low-lying catchment condition was favorable to CaCO3 accumulation. 3) The basic cause responsible for the multicycle of CaCO3 migration and accumulation in the Milanggouwan section may be the multiple alterations of winter and summer monsoons over the Mu Us Desert under the influences of climatic fluctuation of glacial and interglacial periods in the Northern Hemisphere since 150ka B. P. .

关键词： Milanggouwan section 150ka B. P. CaCO3, 2. sediment-climatic cycles

Possible effect of solar activity on variation of the tree-rings of a 500 a platycladus orientalis at the Mausoleum of Emperor Huang

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Science China(Physics,mechanics & Astronomy) 2009年第4期52卷 631-639页

作者： FENG Bo1,2.& HAN YanBen1 1 Xi’an institute of Posts & Telecommunications,Xi’an 710061,China 2.National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012.China Xi’an institute of Posts & Telecommunications Xi’an China National Astronomical Observatories Chinese Academy of Sciences Beijing China

The variation of the tree-ring's index of a platycladus orientalis at the Mausoleum of Emperor Huang and of a long series of sunspots relative number during AD1470-1974 are analyzed by using the wavelet power spectrum method,and their variation characters are also discussed. It is determined that the tree-ring's variation has cycles of approximate 2.7,11,93 and 150 a. Two data series are used for analyzing sunspot relative number(SSN) variation. First,the analysis of the annual average SSN during AD1700-1974 proved that variation cycles are about 11,50,and 93 a; then,the data during AD1465-1975 obtained from the decadal average SSN train over 7000 a reconstructed on the geomagnetic data is analyzed and its variation cycles are about 50,90,and 160 a. Besides the tree-rings cycle of 2.7 a is commonly considered to be related to ENSO,while 11 a cycle is related to solar Schwabe cycle; in addition,it is possible that the cycles of 90 and150 a are likely to be related to solar Gleissberg cycle and Suess cycle. The correlations between them are possibly due to the effect of solar activity on the climate and additionally on the tree's growth.

关键词： tree-ring solar activity climate change wavelet spectrum

change of surface cover greenness in China between 2.00 and 2.10

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Chinese Science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4& GONG Peng1,2.31State Key Laboratory of Remote Sensing Science, Jointly Sponsored by institute of Remote Sensing Applications of Chinese Academy of Sciences,and Beijing Normal University, Beijing 100101, China 2.0} for Global {2. Studies & Center for Earth System Science, Tsinghua University, Beijing 100084, China 3Department of Environmental Science, Policy and Management, University of California, Berkeley, CA9472., usa 4Graduate University of Chinese Academy of Sciences, Beijing 100049, China State Key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate University of Chinese Academy of Sciences Beijing China institute for Global change Studies & Center for Earth System Science Tsinghua University Beijing China Department of Environmental Science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2.00 to 2.10 and analyzed their change over China in this *** results showed that an increasing trend of NDVI occurred over 66.84% (OLS fitting) or 64.2.% (LAD fitting) of China,indicating that China's greenness is increasing ***,desertification of China *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by {2. *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in China could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

Typical basin-fill sequences and basin migration in Yanshan, North China ——Response to mesozoic tectonic transition

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Science China Earth Sciences 2004年第2期47卷 181-192页

作者： LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. China University of Geosciences, Beijing 100083, ChinaCorrespondence should be addressed to Li Zhong (email: lizhongd@***) institute of Geology and Geophysics Chinese Academy of Sciences Beijing China China University of Geosciences Beijing China

Basin-fill sequences of mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2., tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, mesozoic, basin-fill, paleocurrent, tectonic transition.

Effect of Cold-rolling on Hardness of SiC_w/Al Composite

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Journal of Wuhan University of Technology(Materials Science) 2004年第4期19卷 40-42页

作者：张文龙 Shanghai Jiaotong University

A SiC w/Al composite was fabricated through a squeeze cast route and cold rolled to about 30%, 50% and 70% reduction in thickness, respectively. The length of whiskers in the composite before and after rolling was examined using SEM. Some of the rolled composites were annealed by recrystallizing to remove the work hardening of the matrix alloy. The hardness of the rolled and annealed SiC w/Al composites was examined and then associated with the change of the whisker length and the work hardening of the matrix alloy. It was found that the hardness was a function of the degree of cold rolling. For the cold rolled composites, with the increase in the degree of cold rolling, the hardness increases at first, and decreases when the degree of cold rolling exceeds 50%. For the annealed ones, however, the hardness decreases monotonously with the increase in rolling degree. The different changes in hardness between the rolled and annealed composites could be attributed to a result of the competition between the work hardening of the matrix resulting from the cold rolling and the work softening arising from the change of whisker length.

关键词： metal matrix composites cold rolling hardness microstructure

Experimental study of thermally-driven micro-pump using stepped laser

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Progress in Natural Science:Materials International 2004年第8期 22-26页

作者： ZHOU Hong 1,2. , HUAI Xiulan 1*, LI Huazhi 2. LIU Dengying 1 and meNG Qun 1(1. institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, China 2. University of Science and Technology, Beijing 100083, China) institute of Engineering Thermophysics，Chinese Academy of Sciences，Beijing 100080，China University of Science and Technology，Beijing 100083，China institute of Engineering Thermophysics，Chinese Academy of Sciences，Beijing 100080，China University of Science and Technology，Beijing 100083，China

The stepped pulse-laser is used to heat the fluid in a micro-tube with the diameter less than 1 mm, and a phase change and a directional flow of the fluid are induced. Based on many experimental observations, the mechanism of thermally-driven meMS is studied and the technical approaches of the efficient and steady thermally-driven flow is given. The experimental results show that the hypostasis of the thermally-driven micro-pump is a kind of erratic liquid-vapor two-phase flow, and the liquid movement and the change rate of the pressure is closely related to the bubbles' behavior in the micro-tube.

关键词： meMS thermally-driven micro-pump laser micro-tube.

Research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition

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Science China(Technological Sciences) 2009年第9期52卷 2528-2535页

作者： GU ChongShi1,2.WU HaiZhen1,2.& SU HuaiZhi1,2.1 College of Water Resources and Hydropower Engineering,Hohai University,Nanjing 2.0098,China 2.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,Nanjing 2.0098,China 3 Jiangxi Water Conservancy Research institute,Nanchang 33002.,China College of Water Resources and Hydropower Engineering Hohai University Nanjing China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing China Jiangxi Water Conservancy Research institute Nanchang China

The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope engineering's failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

关键词： reservoir bank slope rock-soil aggregates rainfall infiltration saturated/unsaturated seepage

The terrestrial NPP simulations in China since Last Glacial Maximum

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Science Bulletin 2005年第18期 108-113页

作者： HE Yong1, DAN Li2. DONG Wenjie1,2. JI Jinjun3,2.& QIN Dahe1 1. National climate Center, China meteorological Administration, Bei-jing 100081, China 2. Key Laboratory of Regional climate-Environment for Temperate East Asia, {2. of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China 3. {2. of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China

Based on Atmosphere-Vegetation Interaction Model (AVIM), the magnitude and spatial distribution of terrestrial net primary productivity (NPP) in China is simu-lated during three different geological eras, Last Glacial Maximum (LGM), Mid-Holocene (MH) and the present. The simulation shows that the glacial-interglacial variation of East Asian summer monsoon in China is the key factor af-fecting the NPP change. During the three eras, mean NPPs are 2.8 g/m2.a, 409 g/m2.a, and 355 g/m2.a. The total NPPs are 2.05 Pg/a, 3.89 Pg/a and 3.33 Pg/a, respectively. The ter-restrial NPP in China during warm-humid climate is larger than that during cold-arid eras, and the correlation analysis between NPP and climate factors suggests that temperature is the primary factor affecting the terrestrial NPP during 2. kaBP (LGM), and for 6 kaBP (MH) and the present the pri-mary factor is precipitation.

关键词： Last Glacial Maximum Mid-Holocene NPP East-Asian monsoon climate change.