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Measurement of respiration amount of white birch（Betula platyphylla）population in the mountainous region of beijing

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Journal of Environmental sciences 1995年第4期7卷 391-398页

作者： Fang Jingyun, Wang Xiaoke(Research center for Eco - Environmental sciences ,chinese academy of sciences, beijing 100085 , china)

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Ｍｅａｓｕｒｅｍｅｎｔｏｆｒｅｓｐｉｒａｔｉｏｎａｍｏｕｎｔｏｆｗｈｉｔｅｂｉｒｃｈ（Ｂｅｔｕｌａｐｌａｔｙｐｈｙｌｌａ）ｐｏｐｕｌａｔｉｏｎｉｎｔｈｅｍｏｕｎｔａｉｎｏｕｓｒｅｇｉｏｎｏｆＢｅｉｊｉｎｇＦａｎｇＪｉｎｇｙｕｎ，ＷａｎｇＸｉａｏｋｅ（...

关键词： diameter distribution mountainous region of beijing respiration white birch population.

SOLID PHASE TRANSITION OF SYNDIOTACTIC POLYSTYRENE IN SUPERCRITICAL CO_2

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chinese Journal of Polymer Science 2002年第3期20卷 191-196页

作者： Yu-ying Li Jia-song He State Key Laboratory of Engineering Plastics, center for Molecular Science, institute of Chemistry chinese academy of sciences, beijing 100080 china chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

Solid phase transition of the a form crystals to the 3 form crystals in syndiotactic polystyrene (sPS) samples has occurred in supercritical CO2. This transformation is different from those detected under other conditions. The effects of some factors (e.g. time, temperature, and pressure) on the solid phase transformation of sPS in supercritical CO2 were analyzed in detail. Experimental results show that longer time, higher temperature or higher pressure favors the transformation of the a form crystals to the beta form crystals.

关键词： solid phase transition syndiotactic polystyrene supercritical CO2

Anaerobic　biodegradability　of　terephthalic　acid　and　its　inhibitory　effect　on　anaerobic　digestion

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Journal of Environmental sciences 1994年第2期6卷 180-188页

作者： Kuang Xin Wang Jusi(Research center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china)

The behavior of terephthalic acid (TPA) in anaerobic system has been studied bysemicontinuous bioassays under mesophilic condition with artificial TPA production wastewater. Theeffect of different loading rate of TPA on anaerobic digestion was studied under certain CODloading rate. The results showed that the TPA could be degraded anaerobically within a relativelylow range. The degradable concentration of TPA was less than 500 mg/L in the digester, higherconcentration of TPA could not be degraded totally and the rate of degradation might decrease withthe increase of feed amount. The inhibition is related to both loading rate and accumulatedconcentration of TPA in the digesters.

关键词： anaerobic biodegradability terephthalic acid inhibitory effect semi-continuous bioassay ac-cumulated concentration .

Thermal stability of oxygen evolution in photosystem Ⅱ core complex in the presence of digalactosyl diacylglycerol

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chinese Science Bulletin 2002年第24期47卷 2089-2092页

作者： YANG Zhenle, LI Liangbi & KUANG TingyunPhotosynthesis Research center, institute of Botany, chinese academy of sciences, beijing 100093, china Photosynthesis Research center Institute of Botany Chinese Academy of Sciences Beijing China

The influence of digalactosyldiacylglycerol (DGDG), one of the photosynthetic membrane lipids, on heat inactivation of the process of oxygen evolution has been studied in vitro in photosystem Ⅱ(PS Ⅱ) core complex. It was found that the temperature of semi-inactivation of oxygen evolution in the complex increased from 40.0 to about 43.0℃ in the presence of DGDG with 5-min heat treatment in the dark. Furthermore, when PS Ⅱ core complex was incubated for 5 min at 45.0℃, the oxygen evolution in the complex was completely lost, whilst the DGDG-complexed PS Ⅱ core complex still retained a 16% of activity (100% for 25.0℃). In addition, a 1-h incubation at 38.0℃ inactivated absolutely the oxygen evolution for the PS Ⅱ core complex. By contrast, there remained about 20% of activity (zero time for 100%) for the complex in the presence of DGDG under the same condition. These results indicate a new role of DGDG in the protection of PS Ⅱ core complex against the deleterious effects of temperature. It was

关键词： digalactosyl diacylglycerol photosystem Ⅱ core complex extrinsic protein of 33 kD thermal stability oxygen evolution.

The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china(Technological sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems Ecology, Research center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of chinese academy of sciences, beijing 100101, china 1. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

^(40)Ar-^(39)Ar thermochronology of two ductile shear zones from Yiwulüshan,West Liaoning Region: Age constraints on the Mesozoic tectonic events

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chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU ZhipingResearch center of Mineral Resources Exploration, institute of Geology and Geophysics, chinese academy of sciences, beijing 100101, china Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 51 Research center of Mineral Resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North china, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 40Ar-39Ar plateau age of (219±4) Ma (Bi) and two samples from the latter gave 40Ar-39Ar plateau ages of (116± 2) Ma (Bi) and (127±3) Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 40Ar-39Ar age biotite ductile shear zone West Liaoning Region.

MB_8^(2-) (M=Be,Mg,Ca,Sr,and Ba):Planar octacoordinate alkaline earth metal atoms enclosed by boron rings

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Science china Chemistry 2010年第8期53卷 1737-1745,1829-1832页

作者： PU ZhiFeng1,GE MaoFa1 & LI QianShu2 1State Key Laboratory for Structural Chemistry of Unstable and Stable Species beijing National Laboratory for Molecular sciences (BNLMS) institute of Chemistry,chinese academy of sciences,beijing 100190,china 2center for Computational Quantum Chemistry,South china Normal University,Guangzhou 510631,china 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species beijing National Laboratory for Molecular sciences (BNLMS) institute of Chemistry Chinese Academy of Sciences Beijing 100190 China2. Center for Computational Quantum Chemistry South China Normal University Guangzhou 510631 China

Complexes involving planar octacoordinate alkaline earth metal atoms in the centers of eight-membered boron rings have been investigated by two density functional theory (DFT) ***82-with D8h symmetry is predicted to be stable,both geometrically and electronically,since a good match is achieved between the size of the central beryllium atom and the eight-membered boron *** contrast,the other alkaline earth metal atoms cannot be stabilized in the center of a planar eight-membered boron ring because of their large *** following the out-of-plane imaginary vibrational frequency,pyramidal C8v MgB82-,CaB82-,SrB82-,and BaB82-structures are *** presence of delocalized π and σ valence molecular orbitals in D8h BeB82-gives rise to aromaticity,which is reflected by the value of the nucleus-independent chemical *** D8h BeB82-structure is confirmed to be the global minimum on the potential energy surface.

关键词： density functional theory octacoordinate alkaline earth metal aromatic molecular orbital

Numerical experiments for the impacts of temperature and precipitation variation on the growth and development of winter wheat

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Journal of Environmental sciences 1993年第2期5卷 194-200页

作者： Zhang YuAgrometeorological Research center, chinese academy of Meteorological sciences, beijing 100081, china Agrometeorological Research center Chinese Academy of Meteorological Sciences Beijing 10081 China. China

The growth process of winter wheat was simulated by CERES-wheat model assuming the daily temperature increase -1, 0,1, 2℃ and daily precipitation increase -20, -10, -5, 0, 5, 10, and 20 percent, respectively. The case study site is Zhenjiang City of Jiangsu Province in the east china. Simulation results show that the impacts of temperature variation on winter wheat is stronger than that of precipitation. Climate warming would speed development rate and shorten phonological period. In general, the adverse effect of climate change on grain yield is greater than that of its beneficial effect, especially when the climate becoming cooler and dryer. The increase of temperature and decrease of precipitation would reduce the plant extractablc soil water content.

关键词： climate change winter wheat CERES-wheat model.

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3 1. National Marine Environmental Forecasting center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 3. Graduate University of chinese academy of sciences, beijing 100049, china 1. National Marine Environmental Forecasting center Beijing 100081 China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Graduate University of chinese academy of sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.