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Triaxial ellipsoid models of the Moon based on the laser altimetry data of Chang'E-1

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Science china Earth sciences 2010年第11期53卷 1594-1601页

作者： WANg WenRui1,2,3, LI Fei1, LIU JianJun1, REN Xin2, ZOU XiaoDuan2,3, MU LingLi2, YAN Jianguo1, ZOU YongLiao2, ZHANg HongBo2, Lü Chang2, LIU JianZhong2, ZUO Wei2, SU Yan2, WEN WeiBin2, BIAN Wei2, WANg Min2, LI ChunLai2 & OUYANg ZiYuan2 1 school of geodesy and geomatics, Wuhan University, Wuhan 430079, china 2 National Astronomical Observatory of chinese academy of sciences, beijing 100012, china 3 g.aduate school of chinese academy of sciences, beijing 100049, china school of geodesy and geomatics Wuhan University Wuhan China National Astronomical Observatory of chinese academy of sciences Beijing China g.aduate school of chinese academy of sciences Beijing China

Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic parameters as the principle moment of inertia, the principle inertia axes, equatorial radius, polar radius, mean radius, flattening and offset between center of mass and center of figure (DCOM-COF). According to the CE-1 altimetry data and the above geodetic parameters, a tri-axial ellipsoid (CE-1-LAM-gEO) and a tri-axial level ellipsoid (CE-1-LAM-LEVEL) are calculated individually, providing mass center and figure center offset (DCOM-COF) and parameters more reliable in direction and magnitude.

关键词： Chang’E-1 laser altimetry data lunar ellipsoid lunar gravity

Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

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chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU Weiguo1,2 & WANg Zheng1,3 1 State Key Laboratory of Loess and Quaternary geology, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2 Xi’an Jiaotong University, school of Human Settlement and Civil Engineering, Xi’an 710049, china 3 g.aduate University of chinese academy of sciences, beijing 100049, china State Key Laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China school of Human Settlement and Civil Engineering Xi’an Jiaotong University Xi’an China g.aduate University of chinese academy of sciences Beijing China

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern china, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern china under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2‰ to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3‰ to 7.2‰ with average of 4.1‰; and (2) mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for environmental changes.

关键词：氮同位素物理性质化学性质环境论

Preparation and characterization of a novel adsorbent for removing lipophilic organic from water

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Science china Chemistry 2005年第6期48卷 600-604页

作者： LIU Huijuan1, DAI Ruihua1, QU Jiuhui1 & RU Jia1,2 1. State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china 2. g.aduate school of the chinese academy of sciences, beijing 100039, china State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China g.aduate school of the chinese academy of sciences Beijing China

A novel composite adsorbent containing a kind of lipid-triolein is studied. The ad-sorbent is prepared by embedding triolein into cellulose acetate (CA) sphere. The preparation method, the physical-chemical properties of the adsorbent and the removal efficiency of two or-ganochlorinated pesticides are studied. The adsorbent is stable in water and no triolein leaks into water for 465 h soaking. The adsorbent has high adsorption capacity for organochlorinated pes-ticides such as dieldrin and aldrin. The results suggest that triolein-containing adsorbent could serve as a good adsorbent for lipophilic organic pollutants. The adsorption rate for lipophilic pol-lutants is very fast and has relation with the logKow of the compounds.

关键词： triolein, cellulose acetate, adsorbent, lipophilic organic, drinking water.

Relationships between tree-ring width index and NDVI of grassland in Delingha

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chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3 & SHAO Xuemei1,21. Institute of geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 2. Institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, china 3. g.aduate school of chinese academy of sciences, beijing 100039, china Institute of geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China g.aduate school of chinese academy of sciences Beijing China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3) The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

Twistor bundle theory and its application

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Science china Mathematics 2004年第4期47卷 605-616页

作者： PENg Chia-Kuei & TANg ZizhouDepartment of Mathematics, g.aduate school of chinese academy of sciences, beijing 100039, china Department of Mathematical sciences, Tsinghua University, beijing 100084, china Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing China Department of Mathematical sciences Tsinghua University Beijing China

Over an oriented even dimensional Riemannian manifold(M 2m ,ds2 ), in terms of the Levi-Civita connection form Ω and the canonical form Θ on the bundle of positive orthonormal frames, we give a detailed description of the twistor bundle Гm = SO(2m)/U(m)? J +(@#@ M,ds2 ) →M. The integrability on an almost complex structureJ compatible with the metric and the orientation, is shown to be equivalent to the fact that the corresponding cross section of the twistor bundle is holomorphic with respect toJ and the canonical almost complex structureJ 1 onJ +(M,ds2 ), by using moving frame theory. Moreover, for various metrics and a fixed orientation onM, a canonical bundle isomorphism is established. As a consequence, we generalize a celebrated theorem of LeBrun.

关键词： almost complex structure, integrability, twistor bundle.

Virus rejection with two model human enteric viruses in membrane bioreactor system

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Science china Chemistry 2007年第3期50卷 397-404页

作者： ZHENg Xiang1,2 & LIU JunXin1 1 Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china 2 school of Environment & Natural Resources, Renmin University of china, beijing 100872, china Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China school of Environment & Natural Resources Renmin University of China Beijing 100872 China

A membrane bioreactor (MBR) with gravity drain was tested for virus rejection with two coliphages, T4 and f2, which were used as surrogates for human enteric viruses. Virus rejection was investigated by PVDF and PP membrane modules, with the pore sizes of 0.22 and 0.1 μm, respectively. In tap water system, 2.1 lg rejection of coliphage T4 could be achieved by PVDF membrane compared with complete rejection by PP membrane, while for coliphage f2 with smaller diameter, 0.3―0.5 lg rejection of the influent virus was removed by the two membranes. In domestic wastewater system, cake layer and gel layer on the membrane surface changed the cut-off size of the membrane so that there was no significant difference between PP and PVDF for each coliphage. The removal ratios of coliphage T4 and f2 in the MBR were more than 5.5 and 3.0 lg, respectively. Compared with 5.5 lg removal for virus T4 in the MBR system, only 2.1 lg (96.8%―99.9%) removal rate was observed in the conventional activated sludge system with the influent virus concentration fluctuating from 1830 to 57000 PFU/mL. Only 0.8%―22% virus removal was the effect of adsorption to activated sludge, which showed a decreasing tendency with the retention time, while 75%―98% was the effect of virus inactivation by microbial activity. It indicated that the major mechanism of virus removal was not the transfer of viruses from the water phase to the sludge phase but inactivation in the biological treatment process.

关键词： MBR model virus enteric virus inactivation

Identification of the Angel -related elements in cyprinid fishes and their phylogenetic implications

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Progress in Natural Science:Materials International 2007年第2期17卷 168-171页

作者： WANg Li, HE Shunping and CHEN Yiyu ( Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china g.aduate school of the chinese academy of sciences, beijing 100039, china National Natural Science Foundation of china, beijing 100085, china) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China g.aduate school of the chinese academy of sciences Beijing 100039 China National Natural Science Foundation of china Beijing 100085 China

Angel-related element belongs to the family of miniature inverted-repeat transposable elements (MITEs). In this paper we report the identification of an Angel- related element in the series Leuciscini of cyprinid fishes, which is located in the second intron of the growth hormone (gH) gene. We have also found that this element is absent in orthologous locus in the series Barbini of cyprinid fishes, that provides new evidence for the monophyly of the series Leuciscini. The insertion of Angel -related element into the gH gene might take place in the common ancestor of the series Leuciscini after its divergence from the series Barbini. The high sequence divergence and relatively broad species distribution of Angel-related elements implies that they might be ancient transposons which appeared about 26 million years ago.

关键词： Angel -related elements the series Leuciscini monophyly.

Effect of the Small Reaustenized grains on the Mechanical Properties of a HSLA Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 312-315页

作者： ZHAO Lian-yu 1,2,WEI Yan 1,SHAN Yi-yin 1,YANg Ke 1 (1.Institute of Metal Research,chinese academy of sciences,Shenyang 110016,Liaoning,china 2.g.aduate school of chinese academy of sciences,beijing 100049,china) chinese Acad Sci Inst Met Res Shenyang 110016 Liaoning Peoples R China chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

grain refinement improves not only strength but also *** reaustenized grains were discovered to form along the grain boundaries and lath boundaries in an as rolled high-strength low-alloy (HSLA) steel when heated to double phase *** number and size of the small reaustenized grains were revealed to depend mainly on temperature in the range of 700 to 760℃.These small reaustenized grains were deduced to form by consuming *** mechanical property tests showed that they resulted in slight changes to tensile ***,the sample heated at 740℃ produced a peak Charpy V-notch (CVN) impact energy of 248J when tested at-30℃.Fractography showed that the facture surface of the 740℃ heated impact sample exhibited the smallest brittle zone away from the notch root and a large dimple zone lay ahead of the notch tip,which demonstrated the highest toughness.

关键词： high-strength low-alloy steel reaustenization grain refinement tensile property

Novel gaseous transient species:generation and characterization

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Science china Chemistry 2007年第2期50卷 145-169页

作者： ZENg XiaoQing1,2 & WANg DianXun11 State Key Laboratory for Structural Chemistry of Unstable and Stable Species,Institute of Chemistry,chinese academy of Sci-ences,beijing 100080,china 2 g.aduate school of chinese academy of sciences,beijing 100039,china State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China g.aduate school of chinese academy of sciences Beijing China

Due to special properties of transient species, such as short-lived, unstable, reactive, and even explosive, the generation and subsequent characterization is a great challenge for experimental chemists. In our laboratory, systematic researches have been carried out to investigate novel transient species: reactive halogen species (RHS), short-lived free radicals, and metastable pseudohalogen compounds, based on the successive technical improvements on the Hel Photoelectron spectroscopy (PES). In this review, the topic mainly focuses on innovative methods of generating novel transient species, and subsequent geometric and electronic structure characterizations of these species combined with quantum chemical calculations.

关键词： reactive halogen species radicals pseudohalogen compounds Hel Photoelectron Spectroscopy (PES) quantum chemical calculations