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energy Scattering for the Generalized Davey-Stewartson Equations

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Acta Mathematicae Applicatae Sinica 2003年第2期19卷 333-340页

作者： Cheng-chun Haoacademy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china academy of Mathematics and System sciences Chinese Academy of Sciences Beijing China

Abstract Considering the generalized Davey-Stewartson equation $i\mathop u\limits^. - \Delta u + \lambda \left| u \right|^p u + \mu E\left( {\left| u \right|^q } \right)\left| u \right|^{q - 2} u = 0$ where $\lambda > 0,\mu \ge 0,E = F^{ - 1} \left( {\xi _1^2 /\left| \xi \right|^2 } \right)F$ we obtain the existence of scattering operator in ^(A↑^n) := { u ] H1(A↑^n) : |x|u ] L2(A↑^n)}.

关键词： Keywords Generalized Davey-Stewartson equation pseudo conformally invariant conservation law scattering operator

Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science china Earth sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2, DING Yihui3.& ZHANG Renhe2 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 21004., china 2. State Key Laboratory of Severe Weather (LaSW), chinese academy of Meteorological {3., beijing 100081, china 3. National Climate Center, chinese Meteorological Administration, beijing 100081, china 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. National Climate Center Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical {4. belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical {4. and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

Numerical simulation of the sensitivity of the Pacific subtropical-tropical meridional cell to global warming

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Progress in Natural Science:Materials International 2006年第5期16卷 507-511页

作者： ZHOU Tianjun, YU Yongqiang, LIU Hailong, LI Wei and YU Rucong (LASG, Institute of Atmospheric physics, chinese academy of {3., {4. 100029, china) [a]LASG Institute of Atmospheric Physics Chinese Academy of Science Beijing China

Sensitivity of the Pacific subtropical-tropical meridional cell to global warming is examined by using a global ocean-atmosphere coupled model developed at LASG/IAP. Results indicate that associated with the increasing of atmospheric carbon dioxide, the most prominent signals of global warming locate at high latitudes, and the change of middle and low latitudes, in particular the surface wind, is relatively weak, which leads to a weak response of the Pacific subtropical-tropical meridional cell. At the time of atmospheric carbon dioxide doubling, the change of the meridional cell strength is smaller than the amplitude of natural variability.

关键词： Pacific subtropical-tropical meridional cell global warming ocean-atmosphere coupled model.

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2,3.1. china Institute of Atomic energy, beijing 1024.3. china 2. Center of Nuclear Theoretical physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 73.000, china 3. Institute of Theoretical physics, chinese academy of sciences, beijing 100080, china Correspondence should be addressed to Rong Jian (email: jrong@***) 1. china Institute of Atomic energy 102413 Beijing China 2. Center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou 730000 Lanzhou China 3. Institute of Theoretical physics Chinese Academy of Sciences 100080 Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Status of study on biological and toxicological effects of nanoscale materials

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Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3.1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab), Institute of high energy {3., Chi-nese academy of sciences, beijing 10004., china 2. College of Chemistry and Molecular Engineering, Peking University, beijing 100871, china 3. Department of Occupational and Environmental Health sciences, School of Public Health, Peking University, beijing 100083. china 1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 3. Department of Occupational and Environmental Health sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, YUAN Wei2 & GAO YuZhong3.1 Nansen-Zhu International Research Centre, Institute of Atmospheric physics, chinese academy of {3., beijing 100029, china 2 china Meteorological Administration Training Centre, beijing 100081, china 3.Heilongjiang Meteorological Observatory, Harbin 15003., china 1. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. china Meteorological Administration Training Centre Beijing 100081 China 3. Heilongjiang Meteorological Observatory Harbin 150030 China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change

Recent progress in single chip white light-emitting diodes with the InGaN underlying layer

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 445-448页

作者： WANG XiaoLi, WANG XiaoHui, JIA HaiQiang, XING ZhiGang & CHEN Hong beijing National Laboratory of Condensed Matter, Institute of physics, chinese {3. of {4., beijing 100080, china 1. beijing National Laboratory of Condensed Matter Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Tremendous progress has been achieved in white light-emitting diodes (LEDs). To further improve the quality of white light and simplify the fabrication process, a single chip white-light LED with the InGaN underlying layer (UL) was studied and fabricated. The turn-on voltage of this type of LED was 2.7 V, and the spectrum at a forward bias current of 20 mA was comprised of blue (4.3.nm) and yellow (563.nm) lights. The intensity ratio of blue to yellow light was almost constant with the in- creasing injection current in a certain scope, most important for the solid state illumination. The useful life test showed the light output level remained at a 90% light output level at the driving current of 4. mA after 3.0 h, meanwhile, the UV and blue LEDs combined with phosphor reached a 20% value after 14. h within 3.0 h.

关键词： GaN InGaN white light LED MOCVD

Mechanisms of invasive population establishment and spread of pinewood nematodes in china

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Science china(Life sciences) 2009年第6期52卷 587-594页

作者： XIE BingYan1,CHENG XinYue2,SHI Juan3.ZHANG QingWen4.DAI ShuMing1,CHENG Fei Xue2 & LUO YouQing3.1 Institute of Vegetables and Flowers,chinese academy of Agricultural {4.,{3. 100081,china 2 {3. Normal University,{3. 100875,china 3.{3. Forestry University,{3. 100083.china 4.chinese Agricultural University,{3. 100094.china 1. Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 China 2. beijing Normal University Beijing 100875 China 3. beijing Forestry University Beijing 100083 China 4. chinese Agricultural University Beijing 100094 China

This paper summarizes the results of our study of the pinewood nematode(Bursaphelenchus xylophi-lus).By population genetic analysis,it was determined that there was no genetic bottle caused by the founder effect and genetic drift in the chinese invasive *** invasions with large amounts of nematodes from different sources led to rich genetic diversity in the invasive *** high genetic diversity in the invasive process may be one of the genetic mechanisms in its successful *** testing interspecies competition,it was shown that,with high fecundity and a strong competitive ability,*** outcompeted the native species *** in the natural ecosystem during the invasion *** displacement may be one of the ecological mechanisms of ***'s *** addition,an unequal interspecific hybridization with intro-gress was in favor of the invasive species which also accelerated the replacement of *** by *** structures,functions and evolutions of a few important genes that are closely related to the ecological adaptation of pinewood nematodes were studied to explore the molecular mechanism of its ecological ***,the resistance and resilience mechanism of the pine ecosystem invaded by pinewood nematodes was also *** results of these studies uncovered a portion of the genetic and ecological mechanisms of PWN's successful invasion and laid a foundation for further study to obtain a comprehensive interpretation of the mechanisms of the nematode *** results also provided a scientific basis for effectively controlling the occurrence and spread of pine wilt disease which is caused by *** aspects requiring further investigation are considered.

关键词： pinewood nematode bioinvasion genetic diversity ecological adaptation resistance resilience

CH_4.uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

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Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2 & YUAN GuoFu1 1 Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, {4. 100101, china 2 Graduate University of chinese academy of sciences, {4. 10004., china 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4.concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4.uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4.uptake flux was positively correlated with near ground atmosphere CH4.concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4.flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2 d?1 (all plants were removed), respectively. The difference between the CH4.flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4.uptake flux is smaller than that of roots or roots-removing process. CH4.uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.3.–7.86). The Leymus chinensis steppe acts as a sink for CH4. and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method