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^(234.Th/^(238)U disequilibrium and particulate organic carbon export in the northwestern South china Sea

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Acta Oceanologica Sinica 2011年第3期30卷 55-62页

作者： MA Hao ZENG Zhi YU Wen HE Jianhua CHEN Liqi CHENG Jianping YIN Mingduan ZENG Shi department of Engineering physics Tsinghua University Beijing 100084 China Key Laboratory of Global Change and Marine-atmospheric Chemistry State Oceanic Administration Xiamen 361005 China Key Laboratory of Particle ＆ Radiation Imaging （Tsinghua university） Ministry of Education Beijing 100084 China Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense Beijing 100084 China

234.h was utilized as a tracer of particulate organic carbon （POC） export in the northwestern South china Sea （SCS） on the basis of the data collected at four stations during a spring cruise. Depth profiles of dissolved and particulate 234.h activities were measured in the upper 60m, showing a significant deficit relative to 23Su over the investigated stations. A stratified structure of 234.h-23su disequilibrium was in general observed in the upper 60 m water column, indicating that the euphotic zone of the northwestern SCS in this reason can be divided into two layers, an upper and lower layer, with different export rates. POC export fluxes were estimated from a one-dimensional steady state model of 234.h fluxes in combination with the measurement of POC/234.h ratios on suspended particles. The POC export in this region ranged from 8.2 to 20.0 mmol/（m2.d）, with an average of 16.0 mmol/（m2-d）, and was slightly higher than those previously reported in the southern SCS.

关键词： 234.h 23su disequilibrium POC export South china Sea

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,{4. 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

VARIATIONAL ITERATION SOLVING METHOD FOR SEA-AIR OSCILLATOR MODEL OF INTERDECADAL CLIMATE FLUCTUATIONS

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Chinese Geographical Science 2005年第3期 37-40页

作者： MO Jia-qi1, 2, LIN Yi-hua3, WANG Hui4.(1. department of Mathematics,Anhui Normal university,Wuhu 24.000,P. R. china 2. Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong university,Shanghai 20024.,P. R. china 3. Institute of atmospheric physics,Chinese Academy of Sciences,Beijing 100029,P. R. china 4. Chinese Academy of Meteorological Sciences,Beijing 100081,P. R.china) department of Mathematics A nhui Normal UniversityWuhu 241000P. R. China Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong UniversityShanghai 200240P. R. China Institute of atmospheric physics Chinese Academy of SciencesBeijing 100029P. R. China Chinese Academy of Meteorological Sciences Beijing 100081P. R. China

atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively.

关键词： nonlinear variational iteration El Nio-Southern Oscillator model

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,Beijing {4.,china2 china Center of Advanced Science and Technology (World Laboratory),Beijing 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 DOMINANT DEFECT AT THE Si/SiO_2 INTERFACE IN MOS STRUCTURE

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Science china Mathematics 1989年第12期32卷 1458-1468页

作者：陈开茅卢殿通 department of physics Peking University Institute of Low Energy Nuclear physics of Beijing Normal university

The interface defects at the Si/SiO_2 interface in ρ-type silicon (111) MOS structures have been studied by the DLTS method. A dominant defect H_(it),(0.503) at the Si/SiO_2 interface has been found. Its characteristics are (i) the average hole ionization Gibbs free energy △G_p≥0.503 eV; (ii) by changing the gate bias when the distance from Fermi level to the top of Si valence band at the Si/SiO_2 interface is less than △G_p there is still the strong DLTS peak; (iii) its hole apparent activation energy increases with the dectease of the height of semiconductor surface potential barrier; and (iv) its hole capture process causes the multiexponential capacitance transience as a function of pulse width and the H_(it)(0.503) level are very difficult to be fully filled with the holes introduced by thepulst with alimited width. All above show that there is a continuous transition energy band between the energy bands of the covalent crystal silicon and the SiO_2 in the Si/SiO_2 systems formed by thermal oxidation; the dominant defect H_(it)(0.503) is distributed in the transition region, and the distance of H_(it)(0.503) level from the top of the valence band increases with the distance from the silicon surface.

关键词： interface defects MOS structure physics model of Si/SiO_2 interface.

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, university of Maryland, Maryland 2074., 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 [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

Energy transfer of n-hexane-tributyl phosphate(TBP)binary system:Using TBP as a probe for the detection of excited states of n-hexane

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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,Beijing 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

Analysis on the Change of china Precipitation and its Possible Cause

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Analysis on the Change of China Precipitation and its Possib...

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

中国气象学会2006年年会“首届研究生年会”分会场

作者： Yunping Lin and Chunsheng Zhao department of atmospheric Science, School of physics, peking university, Beijing,{4.

Based on the daily precipitation data records of 521 stations in china, observed changes in various magnitude of precipitation have been analyzed in the period of 1961-2000. The result indicates that

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来源： cnki会议评论

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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