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Chinese Science Bulletin 1998年第23期43卷 1950-1955页

作者： WANG Xiangyun 1, WANG Chao 2. GUO Huadong 2.and SHI Yangshen 1 1. Department of Earth sciences, Nanjing University, Nanjing 2.0093, china 2. {2. of Remote Sensing Applications, Chinese academy of sciences, Beijing 100101, china Department of Earth sciences Nanjing University Nanjing 210093 China Inst. of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

ERS 1 WSC data were obtained by international cooperation. The distributive characteristics of radar backscattering coefficient image of china land surface are analyzed and the research results are presented. The capability of ERS 1 WSC data for monitoring land surfaces is investigated. The results show that the radar backscattering coefficient images can reveal the natural landform features of china land. Using the WSC data can discriminate six types of major land coverage, including evergreen vegetation and snow covered region, vegetation and crops, mountains, grassland, desert and grassland, desert. On the whole, the radar backscattering coefficient image of china land is the synthesis of the vegetation map and terrain map. Statistical study of the typical terrain shows that the radar backscatter coefficients of china land range from -2. dB to -5.dB. The lowest value corresponds to the deserts of Badain Jaran, Takla Makan, and Tengger. The highest value corresponds to snow covered regions of Himalaya Mountains and Tianshan Mountains.

关键词： ERS 1 WSC radar backscattering coefficient land surfaces coverage.

Theoretical study of aging effects on LaNi_(5. tritium storage

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 676-686页

作者： PING Feilin1,2. JIANG Gang1, ZHANG Lin2.& ZHU Zhenghe1 1. institute of Atomic and Molecular Physics, Sichuan University, chengdu 61006{2. china 2. Research Center of Laser Fusion, Mianyang 62.900, china 1. institute of Atomic and Molecular Physics Sichuan University 610065 Chengdu China 2. Research Center of Laser Fusion 621900 Miangyang China

The electronic structure and energy of La2.i10H12.and La2.i10H11He (He is at tetrahedral, octahedral or twelve-face polyhedral interstitials) double cells have been calculated using the density functional theory. Their equilibrium structure, energy bands, electronic density of states (DOS) and X-ray diffraction are presented and discussed. The results indicate the helium-3 produced due to the decay of tritium is most possibly sited at twelve-face polyhedral and octahedral interstices and changes the thermodynamic properties of LaNi5.tritide system. The changes due to aging such as the reduction in the isotherm plateau pressure, increase of the isotherm plateau slope, and appearance of deeply trapped hydrogen are caused not only by the lattice expansion, but also by modification of the electronic structure due to the presence of He.

关键词： LaNi5 alloy, density functional theory, electronic structure, aging.

Effects of Huangqi (Hex) on Inducing Cell Differentiation and Cell Death in K5.2.and HEL Cells

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 211-217页

作者： Xiao-Dong CHENG1, Chun-Hui HOU1, Xue-Jun ZHANG2. Heng-Yue XIE1, Wei-Ying ZHOU1, Lei YANG2. Shu-Bing ZHANG1, and Ruo-Lan QIAN1 State Key Laboratory of Molecular biology, institute of Biochemistry and Cell biology, Shanghai institutes for Biological sciences, the Chinese {5. of sciences, 32. Yueyang Road, Shanghai 2.0031, china Laboratory of Molecular Cell biology, institute of Biochemistry and Cell biology, Shanghai institutes for Biological sciences, the Chinese {5. of sciences,32. Yueyang Road Shanghai 2.0031,{15. the Chinese {5. of sciences, 32. Yueyang Road, Shanghai 2.0031, china State Key Laboratory of Molecular biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China Laboratory of Molecular Cell biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China

Huangqi (Astragalus membranaceus), a traditional Chinese medicine, has been used to ameliorate side effects of cancer chemotherapy in china. However, little is known about its molecular mechanisms. Here we show that induction of K5.2.or HEL cells with 1.5.mg/ml of Huangqi (Hex) (Components extracted from Huangqi) for 3–5.d results in the expression of β-globin gene in both cell lines and leads to terminal differentiation. Moreover, the apoptosis in HEL cells can be induced by increasing concentration of Huangqi (Hex) to 4.5.mg/ml for 3–5.d. Upregulation of Apaf-1, caspase-3 and acetylcholinesterase (AChE) in HEL cells may play a crucial role in the process of apoptosis. The prospect of inducing expression of adult (β) globin gene and apoptosis selectively in cancer cells is obviously attractive from a therapeutic point of view.

关键词： cell death and differentiation Huangqi (Hex) human erythroleukemia cell lines

Simulating the transfer and fate of hexachlorocyclohexane in recent 5. years in Beijing, china

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Science china Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2.1. institute of Geographical sciences and Natural Resources Research, Chinese {2. of sciences, Beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, Beijing 100871, china 1. institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking Beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 195.―2.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 195.―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 15. t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.0}t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5. that before 1983, and this percentage may descend to 0.5. after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

DISCOVERY AND THE IMPLICATION OF A HYDROTHERMAL-METASOMATIC SKARN DEPOSIT IN GANGDISE TECTONIC ZONE,TIBET

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地学前缘 2000年第S1期7卷 143-144页

作者： Yao Peng 1,Li Jingao 2.WT5.5.BX](1 {2. institute of Geology and Mineral Resources,{2. 610082.china 2.BGMR,Tibet,china)

Hydrothermal activity from a hydrothermal circulatory system is a special geological event, it is of importance to the formation of some massive sulfide deposits (hydrothermal deposits). The Authors think that Jiama polymetallic ore deposit in Gangdise tectonic zone, Tibet is a special skarn deposit i.e. a “hydrothermal\|metasomatic skarn deposit" bound up with benthonic hydrothermal circulatory system. Its important characteristics are as follows: 1 Evolution of the Gangdise island arc in studied area may be divided into three stages Middle Jurassic volcanic arc stage; Middle—Late Jurassic and Early Cretaceous inter arc sedimentary basin stage; and Eogene magmatic arc stage. The deposit is confined to the inter arc sedimentary basin. Existing data indicate that the volcanic arc provided Jiama deposit with abundant ore\|forming material; the inter arc sedimentary basin provided Jiama deposit with absolutely necessary space; the magmatic arc created reconcentration condition for the Jiama deposit.

关键词： skarn deposit hydrothermal circulatory system discovery implication

C-H BOND ACTIVATION AND FUNCTIONALIZATION OF METHANE UNDER MILD CONDITIONS

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分子催化 1990年第S1期4卷 76-84页

作者： Zhang Liangfu , Ding Fujiang, Jin Hong, Jiang Qiongzhong,Yang Qi and Li Guangnian(chengdu institute of Organic Chemistry, Chinese {2. of sciences, chengdu,{5.)

In the presence of Rh（COD）（dppe）Cl （COD=1, 5.cyclootadiene, dppe=1,2.bis-（diphenylphosphino）ethane） and CO, we studied the H/Cl exchange reaction between CH4 and o-dichlorobenzene, and observed that the active species of the reaction is a complex containing dppe and carbonyl ligands. We suggest that the mechanism of exchange reaction may be described by the elementary reaction of oxidative addition and reductive elimination. In the presence of trans-PtHL2./sub>X （L=PEt3, P（n-Pr）3, P（n-Bu）3, PPh3; X=Cl-, Br-, I-, CN-） complexes, we have studied the oxidative chlorination reaction of methane. The catalytic activity was found to be related to the electron-donating properties and the cone angle of tertiary phosphine, as well as the trans-effect of X anionic ligands. In addition to the above reactions, we have also studied the insertion reaction of acetylene into C-H bond of methane catalyzed by organotransition-metal complexes containing heterocyclic chelate ligands, such as bipy, phen and TMEDA, in

关键词： ethane heterocyclic chelate carbonyl acetylene complexes catalyzed anionic oxidative insertion

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, Chinese academy of {2., Guangzhou 5.0640, china 2. Guangzhou Research Center of Gas Hydrate, Chinese academy of {2., Guangzhou 5.0640, china 3. Graduate School of Chinese academy 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

Variations of near-surface atmospheric CO_(2.and H_(2.O concentrations during summer on Muztagata

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Science china Earth sciences 2006年第1期49卷 18-26页

作者： XU Baiqing1,2. YAO Tandong1,2. LU Anxin2. GUO Xuejun, LIU Xianqin2.& LI Zhen2.1. Laboratory of Environment and Process on Tibetan Plateau, institute of Tibetan Plateau Research, Chinese academy of {2., Beijing 100085. china 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research institute and institute of Tibetan Plateau Research, Chinese academy of {2. and Chinese academy of Meteorological {2., china Meteorological Administration, Lanzhou 730000, china 1. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Expeditions during the summers of 2.02.and 2.03 implemented continuous monitoring of near-surface (2.m height) atmospheric CO2.and H2. concentrations at the 45.0 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2.concentrations (of about 5.μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2.concentrations occur between 02.30―05.30 AM (local time) and the minimum levels occur between 12.00―15.30 PM. The atmospheric CO2.concentrations in the summer of 2.02.were around 5.μmol·mol?1 lower than those during the same period of 2.03, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2. content in 2.03 was much lower than that in 2.02.and there exists a striking negative correlation between CO2.and H2. con-centrations. We therefore suggest that the near-surface atmospheric CO2.concentration is affected not only by photosynthesis and respiration, but also by the air H2. content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2. concentration, continuous monitoring, glaciation region, Muztagata.

Calculation of the debris flow concentration based on clay content

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Science china(Technological sciences) 2003年第z1期46卷 163-174页

作者： CHEN Ningsheng, CUI Peng, LIU Zhonggang & WEI Fangqiang institute of Mountain Hazards and Environment, Chinese academy of {2. and Ministry of Water Resources, chengdu 61004., china Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

The debris flow clay content has very tremendous influence on its concentration (γC). It is reported that the concentration can be calculated by applying the relative polynomial based on the clay content. Here one polynomial model and one logarithm model to calculate the concentration based on the clay content for both the ordinary debris flow and viscous debris flow are obtained. The result derives from the statistics and analysis of the relationship between the debris flow concentrations and clay content in 45.debris flow sites located in the southwest of china. The models can be applied for the concentration calculation to those debris flows that are impossible to observe. The models are available to calculate the debris flow concentration, the principles of which are in the clay content affecting on the debris flow formation, movement and suspending particle diameter. The mechanism of the relationship of the clay content and concentration is clear and reliable. The debris flow is usually of micro-viscous when the clay content is low (5. and 10%. But the value decreases with the increasing of the clay content when the clay content is between 10% and 18%. It is apt to transform the soil into the mudflow, when the clay content exceeds 18%. The concentration of the mudflow usually decreases with the increase of the clay content, and this developing tendency reverses to that of the micro-viscous debris flow. There is m

关键词： clay content, debris flow, concentration.

Reconstruction of the most recent common ancestor sequences of SARS-Cov S gene and detection of adaptive evolution in the spike protein

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Chinese Science Bulletin 2004年第12期49卷 1311-1313页

作者： ZHANG Yuan1, ZHENG Nan2.3, HAO Pei4,5.& ZHONG Yang6 1. Laboratory of Systematic and Evolutionary Botany, institute of Bot- any, Chinese {2. of sciences, Beijing 100093, china 2. College of Life sciences, Beijing Normal University, Beijing 100875. china 3. institute of Viral Disease Control and Prevention, Chinese CDC, Beijing 10005., china 4. Bioinformation Center, Shanghai institutes for Biological sciences, Chinese {2. of sciences, Shanghai 2.0031, china 5. Shanghai Center for Bioinformation Technology, Shanghai 2.02.5. china 6. School of Life sciences, Fudan University, Shanghai 2.0433, china 1. Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences 100093 Beijing China 2. College of Life sciences Beijing Normal University 100875 Beijing China 3. institute of Viral Disease Control and Prevention Chinese CDC 100052 Beijing China 4. Bioinformation Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 200031 Shanghai China 5. Shanghai Center for Bioinformation Technology 200235 Shanghai China 6. School of Life sciences Fudan University 200433 Shanghai China

The genome oiganization and expression strategy of severe acute respiratory syndrome coronavirus (SARS-CoV) have been described extensively. As a structural glycoprotein on the virion surface, the spike protein is responsible for binding to host cellular receptors and for the fusion between the viral envelope and the cellular membrane. It also induces neutralizing antibodies in the host and mediates cellular immunity. Previous studies suggested that amino acid replacements in the spike protein coulddramatically alter the pathogenesis and virulence of some coronaviruses. It is therefore reasonable to test the hypothesis that radical amino acid replacements in the spike protein, favored by environmental selective pressure during the process of SARS-CoV interspecific transmission, might make this pathogen adapt to a new host, In this study, we investigated a total of 108 complete sequences of the SARS-CoV S gene from Gen-Bank (until March 2., 2.04). After omission of those records containing frame-shift mutations or low quality sequences, e.g. ZJ01, and selection of one sequence for identical records, an alignment of 42.sequences was obtained using the program Clustal-X. Then, we reconstructed the most recent common ancestor (MRCA) sequences of theSARS-CoV S gene and detected the adaptive evolution in the spike protein.

关键词： SARS冠状病毒自适应进化基因表达糖蛋白分子免疫学波峰病毒