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The bacterial diversity in surface sediment from the South china Sea

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Acta Oceanologica Sinica 2010年第4期29卷 98-105页

作者： WANG Guanghua DONG Junde LI Xiang SUN Huimin Key Laboratory of Marine Bio-resources Sustainable Utilization South China Sea Institute of Oceanology Chinese Academy of Science Guangzhou 510301 China graduate university of chinese academy of science Beijing 100049 China

16S rDNA sequencing results from this study and literatures demonstrate that sediment bacteria in the South china Sea （SCS） were very diverse,which contained 22 of the 24 phyla of bacteria investigated from marine sediment,however,it was very imbalance among *** bacterial diversity from 15 samples which covered a wide range of sediment types from 20 to 3 888 m in depth was studied in DGGE （denature gradient gel electrophoresis） in this *** DGGE results indicate that both sediment bacterial diversity and diversity difference among stations were *** representative and differential fingerprints among samples were recovered and sequenced,phylogenetic analysis indicates that they may belong to Proteobacteria （α-,β-,γ-,δ-,ε-）,Planctomycetes,Firmicutes,Chloroflexi,Acidobacteria,Actinobacteria,Nitrospirae,Gemmatimonadetes,candidate division WS3 and so on,of which,Gemmatimonadetes and candidate division WS3 bacteria were first detected in SCS *** study also shows that bacterial diversity analysis based on DGGE was more potential than traditional 16S rDNA clone library in multiple sample analysis.

关键词： bacterial diversity DGGE marine sediment South china Sea

Fabrication of Transparent Superhydrophilic TiO_2 Nanofilm without UV-irradiation

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稀有金属材料与工程 2012年第S1期41卷 263-267页

作者： Du Wen1,2,Ye Yinping1,Li Hongxuan1,Zhao Fei1,2,Ji Li1,Quan Weilong1,2,Chen Jianmin1,Zhou Huidi1 1 State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,chinese academy of sciences,Lanzhou 730000,china 2 graduate university of chinese academy of science,beijing 100049,china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

A transparent phase-pure anatase TiO2 nanofilm was prepared through magnetron sputtering method,and a subsequent annealing treatment awarded it the superhydrophilic *** make clear the mechanism of the heat-induced superhydrophilicity,the chemical composition and surface morphology of the film were investigated in detail and compared before and after the annealing treatment mainly by field emission scanning electron microscopy(FESEM),X-ray diffraction method(XRD),Raman spectroscopy,and X-ray photoelectron spectroscope(XPS).The results suggest that the probable mechanism is in accordance with the UV-induced mechanism,where the heat-induced surface oxygen vacancies and hydroxyl radicals play important roles for achieving the superhydrophilicity.

关键词： superhydrophilicity transparent TiO2 nanofilms magnetron sputtering annealing treatment

Characteristics and dynamics of the soil seed bank at the north edge of Taklimakan Desert

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science china Earth sciences 2007年第S1期 122-127页

作者： LI Ning1,2, FENG Gu1,3 & TIAN ChangYan1 1 Xinjiang Institute of Ecology and Geography, chinese academy of science , ürümqi 830011, china 2 graduate university of chinese academy of science, beijing 100049, china 3 chinese Agricultural university, College of Resources and Environmental sciences, beijing 100094, china

In order to understand the potential of revegetation of halophytic community at the north edge of Taklimakan Desert, the species structure, storage capacity, the vertical distribution pattern and seasonal dynamics of soil seed bank and their interrelationship with community structure of above-ground plants were investigated. The results show that (i) 9 species were identified from seed bank in different seasons indicating that plant composition in this area was simple. (ii) The seed density in soil was 222±10.79 grain/m2 on average, and showed a seasonal variation range from 132±8.16 grain/m2 in summer to 303±12.70 grain/m2 in autumn. (iii) The similarity coefficient between soil seed bank and above-ground vegetation was 0.778. (iv) Vertically, seed densities declined with soil depth. 82.4% of total seeds were found in the top 3 cm of soil profile. No active seeds were found in soil profile below 6 cm. It is concluded that the seed bank at the north edge of Taklimakan Desert contains active seeds of all plant species observed on above ground, and is able to supply potential contribution to reconstruction of vegetation.

关键词： Taklimakan Desert soil seed bank characteristics dynamics

Preparation and Luminescence Properties of Nano-polycrystalline Cr3+:Lu3Ga5O12

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Preparation and Luminescence Properties of Nano-polycrystall...

橡胶-大叶千斤拔复合生态系统中的植物生长与土壤水分养分动态

第11届全国发光学学术会议

作者： LIU Wen-peng~(1,2*) ZHANG Qing-li~1 DING Li-hua~(1,2) SHAO Shu-fang~(1,2) SUN Dun-lu~1 XIAO Jin~(1,2) YIN Shao-tang~1 1.Anhui Institute of Optics and Fine Mechanics,chinese academy of sciences,Hefei 230031,china 2.graduate university of chinese academy of science,beijing 100049,china

Polycrystalline Cr:LuGaO(Cr:LGG)was obtained by sintering the Cr:LGG precursor, which was synthesized via co-precipitation *** Ga,LuO and CrO were used as starting materials and ammonia as *** X-Ray diffraction patterns(XRD),excitation and emission spectra were *** XRD results show that co-precipitation precursor powder sintered at 1000℃ for 3h has translated into polycrystalline Cr:*** lattice constant and average grain size were 12.173 A and 29 nm,*** excitation spectrum comprises three parts,in which two bands positioned at 462 nm and 608 nm correspond to A→T, A→T transition of Cr and another below 300 nm ascribes to the charge transition of Cr. The emission spectrum extends from 600 nm to 840 nm,which is ascribed to the T→A transition of *** fluorescence decay curve monitored at 703 nm is exponential and the fluorescence decay lifetime is 890 μ*** results indicate that Cr:LGG is a promising material for tunable laser.

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山地学报 2009年第4期27卷 433-441页

作者：庞家平陈明勇唐建维郭贤明曾荣中国科学院西双版纳热带植物园中国科学院研究生院西双版纳国家级自然保护区科研所

对橡胶-大叶千斤拔复合生态系统和橡胶纯林进行连续3 a的对比观测研究,结果表明在橡胶林里种植大叶千斤拔能促进橡胶生长,橡胶平均基径、平均胸径和平均树高分别比橡胶纯林高出11.0%、9.62%和3.78%。与橡胶纯林相比,混作后土壤含水量的... 详细信息

对橡胶-大叶千斤拔复合生态系统和橡胶纯林进行连续3 a的对比观测研究,结果表明在橡胶林里种植大叶千斤拔能促进橡胶生长,橡胶平均基径、平均胸径和平均树高分别比橡胶纯林高出11.0%、9.62%和3.78%。与橡胶纯林相比,混作后土壤含水量的季节变化较为缓和且旱季含水量较高;且0～10 cm和10～30 cm的土壤容重每年分别约下降0.03 g/cm3和0.01～0.02 g/cm3。随着种植年限的增加,土壤中有机质、全氮、全磷、全钾含量都呈现出先降后升的趋势,而在对照中土壤有机质、全氮、全磷、全钾含量均呈现不断下降的趋势。表明混作后植物的生长及土壤养分状况比橡胶纯林都有所改善。

关键词：农林复合系统土壤水分容重土壤养分

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2↑ & WANG ShiJin1 1 Center for Space science and Applied Research, chinese academy of sciences, beijing 100190, china 2 graduate university of chinese academy of sciences, beijing 100049, china Center for Space science and Applied Research Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2004, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2005 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2·srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 26-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

Strong decays of N~*(1535) in an extended chiral quark model

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3 & ZOU BingSong1,2,3 1 Institute of High Energy Physics,chinese academy of sciences,beijing 100049,china 2 Theoretical Physics Center for science Facilities,chinese academy of sciences,beijing 100049,china 3 graduate university of chinese academy of sciences,beijing 100049,china Institute of High Energy Physics Chinese Academy of Sciences Beijing China Theoretical Physics Center for science Facilities Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

The strong decays of the N*(1535) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(1535) contribute significantly to the N*(1535) → Nπ and N*(1535) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(1535) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(1535) strong decays five-quark components

Applications of URANS on predicting unsteady turbulent separated flows

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Acta Mechanica Sinica 2009年第3期25卷 319-324页

作者： Jinglei Xu Huiyang Ma Department of Physics, graduate university of the chinese academy of sciences, 100049 beijing, china Department of Physics Graduate University of the Chinese Academy of Sciences Beijing China

Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2D flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS （URANS）. Some typical linear and nonlinear eddy viscosity turbulence models （LEVM and NLEVM） and a quadratic explicit algebraic stress model （EASM） are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding.

关键词： URANS Nonlinear eddy viscosity turbulencemodel ,Separated flows Circular cylinder

Testing local realism in P → VV decays

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 870-875页

作者： LI JunLi1 & QIAO CongFeng1,2 1Department of Physics,graduate university of chinese academy of sciences,beijing 100049,china 2Theoretical Physics Center for science Facilities(TPCSF),chinese academy of sciences,beijing 100049,china graduate university of chinese academy of sciences Department of Physics Beijing China (GRID:grid.458514.9) graduate university of chinese academy of sciences Department of Physics Beijing China (GRID:grid.458514.9) chinese academy of sciences Theoretical Physics Center for Science Facilities (TPCSF) Beijing China (GRID:grid.9227.e) (ISNI:***)

It was found that the vector meson pair from the pseudoscalar decays can form an entangled *** this work we give out detailed explanations on the polarization correlation of the two entangled vector *** is demonstrated that an experimental test of the Clauser-Horne inequality can be carried out through measuring the azimuthal distribution of four pseudoscalars in the cascade decay ηc→ VV →(PP)(PP),and the measurement of this process is feasible with the current running experiments in tau-charm ***,a brief discussion on the polarization correlation of the two vector mesons from B → VV decays is also presented.

关键词： nonlocality test high energy experiment meson decays