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

作者： SONG Zhiguang1,2.& WANG Cuiping1,3.. State Key Laboratory of Organic Geochemistry, Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640,{2. 2. Guangzhou Research center of Gas Hydrate, chinese academy of sciences, Guangzhou 510640,{2. 3. Graduate School of chinese academy of sciences, beijing 10003.,{2. State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Guangzhou Research center of Gas Hydrate Chinese Academy of Sciences Guangzhou China Graduate School of chinese academy of sciences Beijing 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 13. values are very much depleted in 13. and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13. values of companion n-alkanes range from ?2..4‰ to ?3..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

Relaxation of Chain Extension of Amorphous PET Fiber Above the Glass Transition Temperature

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chinese Chemical Letters 2000年第10期11卷 925-928页

作者： Xin LINGHU, Jun ZHAO, Rui SONG, Qing Rong FAN (Polymer physics Laboratory, center of Molecular Science, {2. of Chemistry,{3., beijing, 100080) Polymer physics Laboratory Center of Molecular Science Institute of Chemistry Beijing 100080 China

The recovery of amorphous PET fiber in global chain orientation but nearly random segmental orientation (GOLR) state was studied by the hot shrinkage measurement above the glass transition temperature. The relaxation curves in the form of di-exponential decay were acquired and the change of two special times with the variation of treating temperature and residual recovery ratio ' was discussed.

关键词： GOLR state PET recovery of chain extension hot shrinkage measurement.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3. ZHANG RenHe2. SUN ShuFen1, BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1 {3. of Atmospheric physics,{2., beijing 10002., china 2.chinese academy of Meteorological sciences, beijing 100081, china 3.Graduate University of{2., beijing 100049, china 4 Cold and Arid Regions Environmental and Engineering Research {3.,{2., Lanzhou 73.000, china 5 The National Snow and Ice Data center, University of Colorado, Boulder, CO 803.9-0449, USA institute of Atmospheric physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China chinese academy of Meteorological {2. Beijing China Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China The National Snow and Ice Data center University of Colorado Boulder USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3. 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

SYNTHESIS AND CHARACTERIZATION OF SILAZANE OLIGOMER CONTAINING 1,1,3.3.5,5-HEXAMETHYLCYCLOTRISILAZANE

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chinese Journal of Polymer Science 2000年第5期18卷 449-452页

作者： Cai-hong Xu Ning Zhou Ze-min Xie center for Molecular Science, institute of Chemistry,{2.,{3., china 中科院化学所北京

A new silazane oligomer containing cyclotrisilazane was synthesized by KH-catalyzed dehydro-coupling reactions between diphenylsilane and 1,1,3.3.5,5-hexamethylcyclotrisilazane (D-3.N)).

关键词： silazane oligomer diphenylsilane cyclotrisilazane dehydro-coupling reaction

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2. JIAN Zhimin3.& HE Jinhai4 1. Nansen-Zhu International Research center, institute of Atmospheric {2., chinese academy of sciences, beijing 10002., china 2. institute of Climate and Environment, chinese academy of Meteoro- logical sciences, beijing 100081, china 3. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china 4. Department of Atmospheric sciences, Nanjing institute of Meteorol- ogy, Nanjing 2.0044, china 5. Graduate School of the chinese academy of sciences, beijing 10003., china Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing China Laboratory of Marine Geology Tongji University Shanghai China Department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Systematic study of survival probability of excited superheavy nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3.& ZHOU ShanGui2.3.1College of Applied sciences, {3. University of Technology, {3. 10012., china 2.4} of Theoretical physics, chinese academy of sciences, {3. 100190, china 3.12} of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 73.000, china College of Applied sciences Beijing University of Technology Beijing China institute of Theoretical physics Chinese Academy of Sciences Beijing China center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The stability of excited superheavy nuclei (SHN) with 100 Z 13. against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

Pressure-induced crystallite breaking in La_(0.7)Sr_(0.3.Mn_(0.9)Fe_(0.1)O_3.nanosolids

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chinese Science Bulletin 1998年第6期43卷 458-461页

作者： ZHENG Fanlei 1, 2. SUI Yu 1, 3. XU Dapeng 1 and SU Wenhui 1, 4 1. Department of physics, Jilin University, Changchun 13.02.,{3. 2. Changchun{2., chinese academy of sciences, Changchun 13.02.,{3. 3. institute of Metal R Department of physics Jilin University Changchun Chinas Changchun institute of physics Chinese Academy of Sciences Changchun China institute of Metal Research Chinese Academy of Sciences Shenyang China International center for Materials physics Chinese Academy of Sceinces Shenyang China center for condensed Matter and Radiation {2. CCAST (World Lab.) Beijing China

In the compacting process of the La 0.7Sr 0.3.n 0.9Fe 0.1O 3.nanosolids under the pressure range of 0.0-4.5 GPa, the apparent pressure-induced crystallite breaking phenomenon in these nanosolids was observed. With increasing pressure up to 4.5 GPa, the average grain size decreases by 46% while the magnetization of nanosolids decrease by 40% and their coercive increases by 3.%. This kind of breaking has a close relation to the existence of oxygen deficiency in La 0.7Sr 0.3.n 0.9Fe 0.1O 3.nanoparticles. A simple and convenient method for preparing the bulk nanosolids with a large number of clean interfaces has been suggested.

关键词： nanosolid pressure-induced breaking high pressure.

Features and distribution patterns of chinese endemic seed plant species

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Journal of Systematics and Evolution 2011年第2期49卷 81-94页

作者： 1,2.3.Ji-Hong HUANG 1,4 Jian-Hua CHEN 5 Jun-Sheng YING 1 Ke-Ping MA 1 (State Key Laboratory of Vegetation and Environmental Change, institute of Botany, chinese academy of sciences, {2. 100093. china) 2.(Graduate University of chinese academy of sciences, {2. 100049, china) 3.(center for Documentation and Information, institute of Botany, chinese academy of sciences, {2. 100093. china) 4 (Zhejiang Normal University, Jinhua 3.0}004, china) 5 (Research center of Systematic and Evolutionary Botany, institute of Botany, chinese academy of sciences, {2. 100093. china) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of chinese academy of sciences Beijing 100049 China) (center for Documentation and Information Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Zhejiang Normal University Jinhua 321004 China) (Research center of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

We compiled and identified a list of chinese endemic seed plant species based on a large number of published references and expert reviews. The characters of these seed plant species and their distribution patterns were described at length. china is rich in endemic seed plants, with a total of 14 93. species (accounting for 52.1% of its total seed plant species) belonging to 1584 genera and 191 families. Temperate families and genera have a significantly higher proportion of endemism than cosmopolitan and tropical ones. The most primitive and derived groups have significantly higher endemism than the other groups. The endemism of tree, shrub, and liana or vine is higher than that of total species; in contrast, the endemism of herb is lower than that of total species. Geographically, these chinese endemic plants are mainly distributed in Yunnan and Sichuan provinces, southwest china. Species richness and proportion of these endemic plants decrease with increased latitude and have a unimodal response to altitude. The peak value of proportion of endemism is at higher altitudes than that of total species and endemic species richness. The proportions of endemic shrub, liana or vine, and herb increase with altitude and have a clear unimodal curve. In contrast, the proportion of tree increases with altitude, with a sudden increase at ～4000 m and has a completely different model. To date, our study provides the most comprehensive list of chinese endemic seed plant species and their basic composition and distribution features.

关键词： biodiversity conservation distribution pattern endemism flora of china seed plants.

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2. ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3.1. International center for Climate and Environment sciences, {2. of Atmospheric physics, chinese academy of sciences, beijing 10002., china 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 2.0044, china 3. beijing {2. of Applied Meteorology, beijing 10002., china International center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing China beijing institute of Applied Meteorology Beijing China

A new 3.VAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3.VAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 2.-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 42. m reach 0.63. and 0.3. psu.

关键词： data assimilation, 3.VAR, sea surface height, ARGO floats.

A shortest path algorithm for moving objects in spatial network databases

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Progress in Natural Science:Materials International 2008年第7期18卷 893-899页

作者： Xiaolan Yin a,b,*, Zhiming Ding c, Jing Li a a Technology center of Software Engineering, institute of Software, {2. {3. of Science, P.O. Box 8718, beijing 100080, china b Graduate University, chinese academy of sciences, beijing 100049, china c Technology center of Basic Software, institute of Software, chinese academy of sciences, beijing 100080, china Technology center of Software Engineering Institute of Software Chinese Academy of Science P.O. Box 8718 Beijing 100080 China Graduate University Chinese Academy of Sciences Beijing 100049 China Technology center of Basic Software Institute of Software Chinese Academy of Sciences Beijing 100080 China

One of the most important kinds of queries in Spatial Network Databases (SNDB) to support location-based services (LBS) is the shortest path query. Given an object in a network, e.g. a location of a car on a road network, and a set of objects of interests, e.g. hotels, gas station, and car, the shortest path query returns the shortest path from the query object to interested objects. The studies of shortest path query have two kinds of ways, online processing and preprocessing. The studies of preprocessing suppose that the interest objects are static. This paper proposes a shortest path algorithm with a set of index structures to support the situation of moving objects. This algorithm can transform a dynamic problem to a static problem. In this paper we focus on road networks. However, our algorithms do not use any domain specific information, and therefore can be applied to any network. This algorithm’s complexity is O(klog2.), and traditional Dijkstra’s complexity is O((i + k)2..

关键词： Moving object Spatial network databases Shortest path index Shortest path