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Statistics of gravity waves in the lower stratosphere over Beijing based on high vertical resolution radiosonde

Science china Earth sciences 2005年第9期 222-232页

作者： BIAN Jianchun, CHEN Hongbin & LU Daren institute of Atmospheric sciences, chinese academy of sciences, Beijing 100029, {3.

The seasonal variation of inertia gravity-wave activity in the lower stratosphere (17―24 km) over Beijing is studied based on the high vertical resolution radionsonde observa- tions (from December 2001 to February 2003. of Beijing Observatory (116°28′E, 3.°48′N). Some of the important gravity-wave parameters, such as intrinsic frequency, and propagation direction, are estimated according to the polarized relation among gravity-wave wind components and temperature. Time series of wave energy show that the largest wave amplitudes occur during the winter and the least during the summer, and the average of the KE:PE ratios is about 2.6. Zonal and meridional wind perturbations have almost the same roots of mean variances, which shows that the wave energy in the lower stratosphere is isotropic horizontally. The motion and tem- perature fields are dominated by waves with vertical wavelengths of 1.5―3.km, which occupy above 80% samples, with a mean value of about 2.3.km. The horizontal wavelengths are mainly distributed between 100―800 km, averaging 445 km. The ratio of the mean horizontal to vertical wavelength is about 200:1, which indicates that the wave propagates nearly horizontally, with a very small vertical angle. The intrinsic frequency is estimated by fitting a polarized ellipse to the wind perturbations after band-filtering waves with a wavelength of 1.5―3.km, and the results show that the intrinsic frequency is dominated by 1f―3.5f, with an averaging value of 2f, corre- sponding to an intrinsic time period of 9 hours. Wave energy is found to propagate mainly upward, and in the horizontal direction, there is clear azimuthal anisotropy, with predominate northwest propagation against the prevailing wind.

关键词： inertia gravity waves lower stratosphere polarized relation intrinsic frequency propagation direction.

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Molecular dynamics simulations of interaction between protein-tyrosine phosphatase 1B and a bidentate inhibitor

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Acta Pharmacologica Sinica 2006年第1期27卷 100-110页

作者： Gui-xia LIU~(2,3.4) Jin-zhi TAN~2 Chun-ying NIU~2 Jian-hua SHEN~(2,3. Xiao-min LUO~2 Xu SHEN~(2,3. Kai-xian CHEN~2 Hua-liang JIANG~(2,3.4)2 Center for Drug Discovery and Design,State Key Laboratory of Drug Research,Shanghai institute of Materia Medica,Shanghai institutes for Biological sciences,{3. academy of sciences,Shanghai 201203.china 3.School of Pharmacy,East china University of Science and Technology Shanghai 20023.,china CenterforDrugDiscoveryandDesign StateKeyLaboratoryofDrugResearchShanghaiInstituteofMateriaMedicaShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesShanghai201203China

Aim:To investigate the dynamic properties of protein-tyrosine phosphatase (PTP)1B and reveal the structural factors responsible for the high inhibitory potencyand selectivity of the inhibitor SNA for ***:We performed moleculardynamics (MD) simulations using a long time-scale for both PTP1B and PTP1Bcomplexed with the inhibitor SNA,the most potent and selective PTP1B inhibitorreported to *** trajectories were analyzed by using principal ***:Trajectory analyses showed that upon binding the ligand,theflexibility of the entire PTP1B molecule *** most notable change is themovement of the *** simulation results also indicated that electro-static interactions contribute more to PTP 1B-SNA complex conformation than thevan der Waals interactions,and that Lys41,Arg47,and Asp48 play important rolesin determining the conformation of the inhibitor SNA and in the potency andselectivity of the *** these,Arg47 contributed *** results werein agreement with previous experimental ***:The informationpresented here suggests that potent and selective PTP1B inhibitors can be de-signed by targeting the surface residues,for example the region containing Lys41,Arg47,and Asp48,instead of the second phosphate binding site (besides theactive phosphate binding site).

关键词： molecular dynamics simulation principal component analysis protein-tyrosine phosphatase 1B type 2 diabetes

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Mechanical Properties and Morphology of the Clay/Waterborne Polyurethane Nanocomposite

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Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 24-27页

作者：张永成王心葵 institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001China

Stable clayl waterborne polyurethane nanocompostie dispersions were synthesized by sulfonated poly （ butylene adipate ） diol , 4,4-diphenylmethane diisocyanate , dimethyl propionic acid, 1,4-butanediol, triethyl amine and clay-water dispersion through a route named prepolymer acetone mixing progress. The reinforced mechanical properties and thermal resistance of films casting from h were examined by dynamic mechanical analyses （ DMA ）, thermogravimetrie analyses （ TGA ） and tensile tests. Furthermore, the morphology of these nanocompostie films and dispersions were observed by transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, wide-angle X-ray diffraction analyses（ WXRD ）. The experimental results reveal that the clay could be predominantly dispersed in the pristine polymer forming nanacomposties, and evidently enhanced the tensile properties and modulus of it. Addhionally, the best-reinforced effect could occur when the clay content was near 1 wt% .

关键词： polyurethane waterborne clay nanacornposties

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Observations of GPS ionospheric scintillations Over Wuhan during geomagnetic storms

Observations of GPS ionospheric scintillations Over Wuhan du...

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中国科学院地质与地球物理研究所2006学术年会

作者： G Li~(1,2,3.,B.Ning1,W.Wan~1,and B.Zhao~(1,2,3. 1 institute of Geology and Geophysics,chinese academy of {3.,Beijing,china 2 Wuhan institute of Physics and Mathematics,CAS,Wuhan,china 3.Graduate School of chinese academy of sciences,Beijing,china

During the two geomagnetic storms which occurred on 1 October 2002 and 22 January 2004,the strong ionospheric scintillations of the GPS L1 band were observed atWuhan station (3..6,114.4,45.8ip),which is situated near the northern crest of the equatorial ionosphere *** found that the intense scintillations were associated with the main phases of the storms and were collocated with the enhancement of the equatorial ionization anomaly (EIA);the co-existence of large- and small-scale irregularities at post-midnight was also found. The results may be relevant regarding the influence of the equatorial ionospheric eastward electric field during geomagnetic *** the other hand,GPS L1 band scintillations were not observed during the other two similar storms on 16 July 2003.and 20 November *** of the reasons is probably that the sporadic E layer observed at the storms inhibited the generation of spread F by changing the Pedersen conductivity and suppressing the upward plasma drift.

关键词： Ionosphere(Ionospheric irregularities Midlatitude ionosphere) - Magnetospheric physics(Storms and substorms)

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A comparative study of magnetic properties between whole cells and isolated magnetosomes of Magnetospirillum magneticum AMB-1

A comparative study of magnetic properties between whole cel...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： LI JinHua~(1,2,3.,PAN YongXin~(1,3.),LIU QingSong~(3.4),QIN HuaFeng~4,DENG ChengLong~4, CHE RenChao~5 & YANG XinAn~5 1 Key Laboratory of the Earth’s Deep Interior,institute of Geology and Geophysics,chinese academy of {3.,Beijing 100029,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3.Franco-chinese Biomineralization and Nano-structures Laboratory,Beijing 100029,china 4 State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,chinese academy of {3.,Beijing 100029,china 5 Beijing National Laboratory for Condensed Matter Physics,institute of Physics,chinese academy of {3.,Beijing 100080,china

The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment,as well as novel nano-biomaterials in biotechnological and biomedical *** carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated *** revealed that AMB-1 synthesized single-domain magnetite magneto-somes, which are arranged in the form of linear fragmental *** distinct differences of magnetic properties between these two samples can be faithfully interpreted in terms of spatial arrangement of magnetosomes and magnetostatic *** the whole cells,the strong intra-chain interactions and weak inter-chain interactions generate behaviors of non-interacting uniaxial single-domain ***δ-ratio is 3.0 and passes the Moskowitz *** contrast,the isolated magnetosome sample has reduced values of coercivity andδ-ratio(1.5),due to increasing three-dimensional magnetostatic interactions and collapse of magnetosome *** observations provide useful insights into applications of the biogenic magnetite(magnetosomes)in magnetic nano-materials and magnetofossils in the paleomagnetic and environmental magnetism.

关键词： Magnetospirillum magneticum AMB-1 isolated magnetosomes hysteresis loop FORC Verwey transition Moskowitz test

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Complex behaviour of trivalent rare earth elements by humic acids

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Journal of Environmental sciences 1998年第3期10卷 47-53页

作者： Geng An chaoResearch institute of Environmental Engineering,Fushun Petroleum institute,Liaoning 113.01,chinaZhang Shen institute of Geography,chinese academy of sciences,Beijing 100101,chinaHarald Hфiland Department of Chemistry,Univers

The complexation behaviours of trivalent rare earth elements (La, Ce, Ho and Yb) by two types of humic acids were investigated under a specified set of conditions. Humic acids show quite different complexation capacities an conditional formation constants with the REEs. Apparently there are two types of binding sites in the functional groups of humic acid, in which the first binding sites have stronger ability than the second. Cerium shows the largest complexation capacities and highest formation constants among the four REEs with two humic acids, this anomaly may be relative to the distribution pattern of the REEs in seawater. The experimental results were comparable to the values of other metals reported and provided the basic data for environmental geochemistry of rare earth elements.

关键词： complex behaviour rare earth elements humic acid.

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Model Research on the Effect of Surface Film on Ammonia Volatilization from Rice Field

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Agricultural sciences in china 2002年第9期1卷 1029-1033页

作者： ZHUANG Shun-yao, YIN Bin and ZHU Zhao-liang(institute of Soil Science , chinese academy of sciences , Nanjing 210008 , P.R.china) institute of Soil Science Chinese Academy 9f Sciences Nanjing 210008 P.R. China

Pan and field experiments were conducted to investigate the effect of surface film on ammonia volatilization from water and paddy soil. The results showed that the addition of the surface film on floodwater reduced the rate of ammonia volatilization, however, the reduction of the latter varied greatly with its rates of addition. Jayaweera-Mikkelsen ammonia volatilization model with the introduction of a parameter Kf, a relative measure of the resistance of the surface film on ammonia volatilization, was used to elucidate the effectiveness of the surface film on lowering ammonia volatilization. The Kf value was calculated from the results ob-

关键词： Surface film Ammonia volatilization J-M model Coefficient of resistance

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Methane Emission from Natural Wetlands in china:Summary of Years 1995-2004 Studies

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Pedosphere 2007年第4期17卷 475-486页

作者： DING Wei-Xin CAI Zu-Cong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）.

From studies undertaken during 1995-2004, annual budgets of CH4 emissions from natural wetlands and its temporal and spatial variations were examined throughout china, and various factors influencing CH4 emissions were also evaluated. The seasonal variation in CH4 emissions that increased with increasing plant growth reached its peak in August; decrease in the emissions was found in freshwater marshes but not in peatlands. Emissions were mainly controlled by temperature and depth of standing water. Low CH4 emissions at the early plant growing stages were not because of deficiency of organic C for CH4 production but because of low temperatures. Low temperatures not only reduced CH4 production but also stimulated CH4 oxidation by lowering the activity of other aerobic microbes which left more 02 in the rhizosphere for methanotrophs. Low summer temperatures （below 20 ℃） in the Qinghai-Tibetan Plateau lowered CH4 production and CH4 emission resulting in little or no seasonal variation of emissions. Diel and spatial variation in CH4 emissions depended on plant species. For plants that transport CH4 using the pressure-driven convective through-flow mechanism, diel variation in CH4 emissions was governed by diel variation of solar energy load （that produces temperature and vapor pressure differences within various plant tissues） and stomatal conductance. For plants that transport gases using the molecular diffusion mechanism only, the diel variation of CH4 emissions was because of differences in the magnitude of O2 produced through photosynthesis and then delivered into the rhizomes and/or rhizosphere for CH4 oxidation. Emergent plants could transport more CH4 than submerged plants because the former transport CH4 directly into the atmosphere rather than into water as do submerged plants where CH4 can be further be oxidized during its diffusion from water to the atmosphere. Emergent plants with high gas transport capacity could not only transport more CH4 into the atmosphe

关键词： diel variation methane emission seasonal variation temporal variation wetland

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A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3.1 Key Laboratory of Ecophysics and Department of Physics,Normal College,Shihezi University,Xinjiang 83.003.china 2 School of Science,East china University of Science and Technology,Shanghai 20023.,china 3.{3. of Theoretical Physics,School of Physics and Information Optoelectronics,Henan University,Kaifeng 475004,china 1. Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Xinjiang 832003 China2. School of Science East China University of Science and Technology Shanghai 200237 China3. Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng 475004 China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3.,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

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Rainfall,Landslide and Debris Flow Intergrowth Relationship in Jiangjia Ravine

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Journal of Mountain Science 2011年第4期8卷 603-610页

作者： HU Mingjian WANG Ren SHEN Jianhua State Key Laboratory of Geomechanics and Geotechnical Engineering Institute o fRock and Soil Mechanics Chinese Academy of Sciences Wuhan 43oo71 China

Jiangjia Ravine is a world-famous debris flow valley in Dongchuan,Yunnan Province,*** year large numbers of landslides and collapses happened and caused enormous damages to people's properties and *** longtime observation and testing in Jiangjia Ravine we had found out one kind of special landslide which had the characteristics of landslide and *** and collapse supplied sufficient materials for debris *** a debris flow broke out,some kind of intergrowth existed among rainfall,landslide and debris *** order to study the intergrowth and some key parameters,we carried out artificial rainfall landslide tests and model experiments to observe the phenomena such as collapse,surface slide and surface *** observing the experimental phenomena and monitoring water contents,the transformation process among landslide deposits and debris flow under the condition of rainfall had been *** results revealed the relationship of this kind of intergrowth among rainfall,landslide and debris flow in Jiangjia ***,it was found that this kind of intergrowth relationship existed only when the moisture content was in a certain *** is,the critical state seemed to be existed in the transformation process.

关键词： Landslide Debris-flow Rainfall Intergrowth Moisture Content Jiangjia Ravine

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