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化学学报(英文版) 1985年第1期3卷 14-20页

作者： YUAN Rong-Yao PAN Xian-Ming WU Ji-Lan Technical physics department,peking university,{4. Technical physics department Peking University Beijing

In this paper TBP labeled with 32p was used as a probe for detecting the excited speciesof *** γ irradiation of n-hexane-TBP binary system,it was found that TBP was sen-sitized by excited n-hexane molecules and a G value of 1.05 was found for the excited state of *** energy transfer mechanism was proposed,and kinetic equation of sensitization was *** calculation is in agreement with experimental results.

关键词： hexane excited ketone irradiation detecting benzene labeled sensitized transferred solute

Use of the advanced microwave sounding unit data to improve typhoon prediction

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Progress in Natural Science:Materials International 2009年第3期19卷 369-376页

作者： Guo Deng a,*, Dalin Zhang b, Tong Zhu c, Angsheng Wang d a National Meteorological Center, beijing 100081, china b department of atmospheric and Oceanic Science, {4. of Maryland, Maryland 2074., USA c Cooperative Institute for Research in the Atmosphere, Colorado State {4., Colorado 80523, USA d Institute of atmospheric physics, Chinese Academy of Sciences, beijing 100029, china [a]National Meteorological Center Beijing 100081 China [b]Department of Atmospheric and Oceanic Science University of Maryland Maryland 20742 USA [c]Cooperative Institute for Research in the Atmosphere Colorado State University Colorado 80523 USA [d]Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The effects of incorporating the advanced microwave sounding unit (AMSU-A) data with a modified Zhu-Zhang-Weng vortex- bogussing algorithm on typhoon prediction are examined through the use of the PSU/NCAR Mesoscale Model version 5 (MM5). The AMSU-A data contain the vertical distribution of the retrieved temperature from satellite brightness temperature, with the geopo- tential height and wind fields derived through a series of statistical and diagnostic calculations. The advantages of the modified vortex- bogussing algorithm include the incorporation of realistic asymmetric typhoon structures, the balanced dynamics with the background field, the easiness to implement and the effcient computations. To test the effciency of this vortex-bogussing algorithm, the Typhoon Dan event in 1999 is simulated by incorporating the derived AMSU-A fields into the initial conditions of the MM5 modeling system. Results show significant improvements in the track and intensity of the storm, as compared to the simulation without the AMSU-A data. Therefore, this modified vortex-bogussing algorithm can be easily implemented on any typhoon modeling system, which will improve the real-time forecast of tropical cyclones.

关键词： AMSU Satellite retrieval Typhoon prediction

X（3872） and Bound State Problem of D0*0（0 D*0）

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原子核物理评论 2009年第S1期 16-21页

作者： LIU Yan-rui1,LIU Xiang2,3,DENG Wei-zhen2 (1 Institute of High Energy physics,Chinese Academy of Sciences,beijing 10004.,china 2 department of physics,peking university,beijing 100871,china 3 Centro de Física Terica,Departamento de Física,Universidade de Coimbra,P-3004.516,Coimbra,Portugal)

We have performed a dynamical calculation of the bound state problem of D0D*0 by considering the pion and sigma meson exchange potential. Our preliminary analysis disfavors the molecular interpretation of X(3872) if we use the experimental D*Dπ coupling constant g=0.59 and a reasonable cutoff around 1 GeV,which is the typical hadronic scale. In contrast,there probably exists a loosely bound S-wave BB* molecular state. Such a molecular state would be rather stable since its dominant decay mode is the radiative decay through B*→Bγ.

关键词： X(3872) bound state molecule

Nonfactorizable B→xc0K Decay and QCD Factorization

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Communications in Theoretical physics 2007年第11期48卷 885-890页

作者： MENG Ce~1 GAO Ying-Jia~1 CHAO Kuang-Ta~(1,2)1 department of physics,peking university,{4. 100871,china2 china Center of Advanced Science and Technology (World Laboratory),{4. 100080,china

We study the unexpectedly large rate for the factorization-forbidden decay B→xK within the QCDfactorization *** use a non-zero gluon mass to regularize the infrared divergences in vertex ***-point singularities arising from spectator corrections are regularized and carefully estimated by the off-shellness *** find that the contributions arising from the vertex and leading-twist spectator corrections are numericallysmall,and the twist-3 spectator contribution with chiral enhancement and linear end-point singularity becomes *** reasonable choices for the parameters,the branching ratio for B→xK decay is estimated tb be in the range(2～4.×10,which is compatible with the Belle and BaBar data.

关键词： B meson decay QCD factorization charmonium

A quantification model for apoptosis in mouse embryos in the early stage of fetation

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Science china(Life Sciences) 2009年第10期52卷 922-927页

作者： WANG PengFei1, FU JianHua1, MA WanYun1, CHEN DieYan1, Lü DanYu2 & BAI WenJia3 1 Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry, department of physics, Tsinghua university, beijing 100084.{4. 2 department of Anatomy & Histology and Embryology, School of Basic Medical Sciences peking university Health Science Center, beijing 100083,{4. 3 department of Automation, Tsinghua university, beijing 100084.{4. 1. Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry Department of Physics Tsinghua University Beijing 100084 China 2. department of Anatomy & Histology and Embryology School of Basic Medical Sciences Peking University Health Science Center Beijing 100083 China 3. department of Automation Tsinghua University Beijing 100084 China

Apoptosis is the most important inducement and modulator for embryos in the early stage of fetation, i.e. after the 8-cell stage, mostly the morula and blastula stage, to proceed to the stage of nonlinear development. Using a two-photon laser scanning microscopy (TPLSM) system, we obtained 3-dimensional (3D) fluorescent images of preimplantation mouse embryos. A model for quantification was established. The statistical results for the spatial location of apoptosis bodies in embryos was obtained following image processing, as well as investigation of the kinetics of apoptosis. It was found that most (70%) apoptosis occurred in the trophectoderm, and the departure between the centroid and geometric center of embryos had a step transition when embryos developed into the 32-cell stage, which was consistent with the theoretical prediction that the blastocele would induce a symmetry break of the distribution of cells in embryos.

关键词： apoptosis preimplantation mouse embryo TPLSM quantification model

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2, ZHUANG Guoshun1,2,3, CHEN Jianmin2 & XUE Huaxin2 1. Center for atmospheric Environment Study, department of Chemistry, beijing Normal university, beijing 100875, china 2. Center for atmospheric Chemistry Study, department of Environ- mental Science and Engineering, Fudan university, Shanghai 2004.3, china 3. LAPC/NZC, Institute of atmospheric physics, NZC/LAPC, Chinese Academy of Sciences, beijing 100029, china Center for atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4. produced could account for up to 4..3% and 4..6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 20, 2002, while Fe2(SO4.3, one of the Fe(III) species on the surface decreased from 67.1% to 4..5% and 4..0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

The theoretical research of basic function method in incompressible viscous flow and its simulations in three-dimensional aneurysms

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 909-918页

作者： SHEN Fang1 & WU WangYi2 1 State Key Laboratory for Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 100190, china 2 State Key Laboratory of Turbulence and Complex Systems & department of Mechanics and Engineering Science, peking university,{4., china 1. State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China 2. State Key Laboratory of Turbulence and Complex Systems & department of Mechanics and Engineering Science Peking University Beijing 100871 China

Basic function method is developed to treat the incompressible viscous flow. Artificial compressibility coefficient, the technique of flux splitting method and the combination of central and upwind schemes are applied to construct the basic function scheme of trigonometric function type for solving three-dimensional incompressible Navier-Stokes equations numerically. To prove the method, flows in finite-length-pipe are calculated, the velocity and pressure distribution of which solved by our method quite coincide with the exact solutions of Poiseuille flow except in the areas of entrance and exit. After the method is proved elementary, the hemodynamics in two-and three-dimensional aneurysms is researched numerically by using the basic function method of trigonometric function type and unstructured grids generation technique. The distributions of velocity, pressure and shear force in steady flow of aneurysms are calculated, and the influence of the shape of the aneurysms on the hemodynamics is studied.

关键词： basic function unstructured grid aneurysm viscous incompressible flow artificial compressibility flux splitting

Random walk modeling of wake dispersion for the exhaust tower of an underground tunnel in urban area

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Journal of Environmental Sciences 1999年第4期11卷 474-479页

作者： JIANG Wei\|mei\+1, YU Hong\|bin\+1, LI Xin\+2 (1.department of atmospheric Sciences, Nanjing university, Nanjing 210093, china 2.LAPC, Institute of atmospheric physics,Chinese Academy of Sciences, beijing 100029, china) department of atmospheric Sciences Nanjing University Nanjing 210093 China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

In this paper, some experimental studies on the impact of effluent from an exhaust tower of an underground tunnel with special construction are reported. By measuring the flow field downstream of the tower in NJU meteorological wind tunnel, some flow characteristics in the make area were established. Based on these, an advanced random\|walk dispersion model was set up and applied successfully to the simulation of dispersion in the wake area. The modelling results were in accordance with wind tunnel measurements. The computed maximum of ground surface concentration in the building case was a factor of 3-4.higher than that in the flat case and appeared much closer to the source. The simulation indicated that random walk modelling is an effective and practical tool for the wake stream impact assessment.

关键词： exhaust tower air pollution in urban area atmospheric dispersion random walk modelling

Hierarchical structures in climate and atmospheric turbulence

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Progress in Natural Science:Materials International 2002年第10期 29-34页

作者： SHE Zhensu, FU Zuntao, CHEN Jiong, LIANG Shuang and LIU Shida(1. State Key Laboratory for Studies of Turbulence and Complex Systems, department of Mechanics and Engineering Sciences, peking university, beijing 100871, china 2. School of {4., peking university, beijing 100871, china 3. LAPC, Institute of atmospheric {4., Chinese Academy of Sciences, beijing 100029, china) State Key Laboratory for Studies of Turbulence and Complex Systems，department of Mechanics and Engineering Sciences，peking university，beijing {4.，china LAPC，Institute of atmospheric physics，Chinese Academy of Sciences，beijing 100029，china School of physics，peking university，beijing {4.，china State Key Laboratory for Studies of Turbulence and Complex Systems，department of Mechanics and Engineering Sciences，peking university，beijing {4.，china School of physics，peking university，beijing {4.，china

The climatic time series encompass many time scales, forming multi-scale climatic variations and hierarchies. The periods and magnitudes of cooling or warming, especially for extreme climatic events, vary with the time scales. On the other hand, high-frequency atmospheric turbulent motions, which are certainly related to the climatic changes, are also typical multi-scale phenomena. In this paper, certain properties of the fluctuations are examined that are invariant with the change of the time scales. Specifically, the existence of a statistical similarity law is demonstrated in climatic time series and in atmospheric turbulent motions. This is the hierarchical similarity law. Further analyses show that the hierarchical similarity law is a general property of multi-scale fluctuation systems. Therefore, the study on the hierarchical similarity law is important for understanding the inherent universal physical mechanism of complex systems in the atmospheric motions.

关键词： climate multi-scale hierarchical structure atmospheric turbulence.

Characteristics of low-frequency oscillations in course of SCS summer monsoon onset

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Acta Oceanologica Sinica 2000年第3期19卷 65-72页

作者：毛江玉谢安宋焱云叶谦 Institute of atmospheric physics Chinese Academy of Sciences Beijing 100029 China

Some of the low-frequency oscillation (LFO) characteristics of summer moan onset over the South china Sea (SCS) are examined based on NCEP/NCAR reanalysis data and OLR from NOAA in the period of 1979-1996. It is found that the SCS summer monsoon is characterized by predominance of low-frequency activities with significant interannual variability closely related with onset time. The LFOs over the SCS strengthen after onset. Composite analyses for LFO components of OLR and kinetic energy indicate that the eastward propagation of LFO over the equatorial Indian Ocean and LFO coming from the western Pacific strongly affect the physical processes responsible for the SCS summer monsoon onset. The SCS is the place where the Indian Ocean LFO links with low-frequency activities over the western pacific during summer monsoon onset.

关键词： Low -frequency oscillation the South china Sea summer moan onset