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

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 academy of sciences, {2. 100101, china 2. Laboratory for Earth Surface Processes, Peking University, {2. 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 195.1}2.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 195.1}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 2.3t 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.

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The formation process and cloud physical characteristics for a typical downburstproducing thunderstorm in beijing

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chinese Science Bulletin 2003年第S2期48卷 77-82页

作者： GUO Xueliang FU Danhong Institute of Almospherie Physics, chinese academy of sciences, beijing 10002..{2. chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China

The formation process and characteristics ofcloud physical structure of a severe thunderstorm accompa-nied with strong wind on 2. August, 2.01 in beijing wasstudied using PSU/NCAR mesoscale model ( MM5. couplingwith a severe storm model with hail-bin microphysics. Theresults show that the specific topography and distributionfeatures of cold/warm current in the beijing region playedprominent roles in forming, developing and maintaining thesevere storm. Due to solar radiation heating and topographiclifting, the convective cells were easily formed when thewesterly airflow passed over high mountainous regions inbeijing. The warm and wet air entered the cloud from itsfrontage and enhanced the convection, and formed a largeamount of graupel/hail particles at the middle and upperportion of the clouds. The precipitation was primarilyformed due to melting of graupel/hail particles. The strongdowndraft was mainly produced by negative buoyancy dueto loading, melting of graupel/hail particles as well asevaporative cooling of rain water. The divergent airflow in-duced by the strong downdraft led to the disastrous burstwinds at the surface and also forced lifting of warm and wetairflow in the moving direction of the storm and formed newclouds that further promoted and maintained the storm de-velopment.

关键词： beijing region thunderstorm and disastrous wind cluud physical features.

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Bio-regeneration of p-complexation desulfurization adsorbents

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Science china Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2. XING Jianmin1, XIONG Xiaochao1,2. SHAN Guobin1,2.& LIU Huizhou1 1. Laboratory of Separation Science and Engineering, Institute of Process Engineering, chinese academy of sciences, beijing 100080,{2. 2. Graduate school of the chinese academy of sciences,beijing 100039,{2. 1. Laboratory of Separation Science and Engineering Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. Graduate school of the chinese academy of sciences 100039 Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2. and then by auto-reduction in helium at 45.℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2.HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2.HBP within 6 h and almost 100% within 2. h, when the volume ratio of oil-to-water was 1/5.mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2.HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95. that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 2. h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.

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Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese academy of {2.,beijing 100012.{5. 2.Graduate school of chinese academy of sciences,beijing 100049,{5. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate school of chinese academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5.（DR5. to study the morphological properties of 1137 nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5.at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5.L⊙ to 10^12.⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5.× 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

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Regional pattern of mercury wet deposition in beijing

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Journal of Environmental sciences 2000年第S1期12卷 77-84页

作者： LIU Jun hua, WANG Wen hua, PENG An (SKLEAC, Research Center for Eco-Environmental sciences, chinese academy of sciences, {2. 100085. china)

The regional pattern of mercury were deposition in beijing was studied. The Hg concentrations in precipitation were detected in 0—0.83 ng/ml(summer) and in 0.371—1.73 ng/ml(winter), under extreme condition up to 3.4 ng/ml in heating periods. The sum of Hg wet deposition was 101.5.1}μg/(m 2.a) within Nov. 1994— Nov. 1995. and 12..09 μg/(m 2.a) within Nov. 1995.— Nov. 1996. The more precipitation fall down, the more Hg was removed from atmosphere, especially in heating periods. Burning coal for heating was thought as the reason of a baseline seasonable with highest Hg levels in winter. The Hg concentration in rainfall decreased with the raining duration, which clearly shows the efficiency of washouting Hg by wet deposition.

关键词： mercury wet deposition beijing

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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5. LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, {2. 100101,{5. 2. Graduate school of the chinese academy of sciences, {2. 100039,{5. 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716,{5. 4. The Ministry of Science and Technology, P. C.{5., {2. 100862.{5. 5. Chengdu Institute of Biology, chinese academy of sciences, Chengdu 610041,{5. 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the chinese academy of sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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Software Engineering Technology for the 2.^(st) Century

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Wuhan University Journal of Natural sciences 2001年第Z1期6卷 152-158页

作者： Cheng Hu Institute of Software, chinese academy of sciences beijing 100080,{2. Institute of Software Chinese Academy of Sciences Beijing 100080 China

In this paper we will discuss the software engineering technology for the 2. st century. First we review development over the last half century, overview application requirement and environment, accept a challenge. Then we outline following software engineering techniques: 1) Process;2. Analysis;3) Design;4) UML;5. Component;6) Java +XML;7) Integrated;8) Quality(ISO9000&CMM).

关键词： software engineering object oriented component Java UML CMM ISO9000

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Reduction of choline acetyltransferase activities in APP770 transgenic mice

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chinese Science Bulletin 2000年第9期45卷 834-838页

作者： LI HuiInstitute of Zoology, chinese academy of sciences, beijing 100080,{2. Institute of Zoology Chinese Academy of Sciences Beijing China

Transgenic mice overexpressing the 770-amino acid isoform of human Alzheimeramyloid precursor protein exhibit extracellular β-amyloid deposits in brain regions including cerebral cortex and hippocampus, which are severely affected in Alzheimer’s disease patients. Significant reduction in choline acetyltransferase (ChAT) activities has been observed in both cortical and hippocampal brain regions in the transgenic mice at the age of 10 months compared with the age-matched non-transgenic mice, but such changes have not been observed in any brain regions of the transgenic mice under the age of 5.months. These results suggest that deposition of β-amyloid can induce changes in the brain cholinergic system of the transgenic mice.

关键词： Alzheimer’s disease β-amyloid cholinergic transgenic.

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Special relativity and theory of gravity via maximum symmetry and localization

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Science china Mathematics 2008年第4期51卷 568-603页

作者： GUO HanYing Institute of Theoretical Physics chinese academy of {2. beijing 100080 {5. 1. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

Like Euclid, Riemann and Lobachevski geometries are on an almost equal footing, based on the principle of relativity of maximum symmetry proposed by Professor Lu Qikeng and the postulate on invariant universal constants c and R, the de Sitter/anti-de Sitter (dS/AdS) special relativity on dS/AdS-space with radius R can be set up on an almost equal footing with Einstein’s special relativity on the Minkowski-space in the case of R→∞.Thus the dS-space is coin-like: a law of inertia in Beltrami atlas with Beltrami time simultaneity for the principle of relativity on one side, and the proper-time simultaneity and a Robertson-Walker-like dS-space with entropy and an accelerated expanding S 3 fitting the cosmological principle on another side.If our universe is asymptotic to the Robertson-Walker-like dS-space of R ? (3/Λ)1/2. it should be slightly closed in O(Λ) with entropy bound S ? 3πc 3 k B /ΛG?. Contrarily, via its asymptotic behavior, it can fix on Beltrami inertial frames without ‘an argument in a circle’ and acts as the origin of inertia.There is a triality of conformal extensions of three kinds of special relativity and their null physics on the projective boundary of a 5.d AdS-space, a null cone modulo projective equivalence [ $ \mathcal{N} $ ] ? ? P (AdS 5.. Thus there should be a dS-space on the boundary of S 5.× AdS 5.as a vacuum of supergravity.In the light of Einstein’s ‘Galilean regions’, gravity should be based on the localized principle of relativity of full maximum symmetry with a gauge-like dynamics. Thus, this may lead to the theory of gravity of corresponding local symmetry. A simple model of dS-gravity characterized by a dimensionless constant g ?(ΛG?/3c 3)1/2.～ 10?61 shows the features on umbilical manifolds of local dS-invariance. Some gravitational effects out of general relativity may play a role as dark matter.The dark universe and its asymptotic behavior may already indicate that the dS special relativity and dS-gravity be the foundati

关键词： special relativity de Sitter invariance gravity local de Sitter invariance umbilical manifold 83A05 83D05 5.A35 5.B5.

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A nontrivial product in the stable homotopy groups of spheres

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Science china Mathematics 2004年第6期47卷 831-841页

作者： LIU XiuguiInstitute of Mathematics, chinese academy of sciences, beijing 100080,{2. 1. Institute of Mathematics Chinese Academy of Sciences 100080 Beijing China

Let A be the mod p Steenrod algebra for p an arbitrary odd prime. In 1962. Liulevicius described h i and b k in Ext* A ’*(Zp,Zp) having bigrading (1, sui— 1) and (2. 2. k+1 x(p— 1)), respectively. In this paper we prove that for p ≥ 7, n ≥ 4 and $3 \leqslant s 2.q + (s - 1)pq + (s - 1)q + s - 3} (Z_p ,Z_p )$ survives to E∞ in the Adams spectral sequence, where q = 2.p — 1).

关键词： stable homotopy groups of spheres Adams spectral sequence Toda-Smith spectra May spectral sequence

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