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IMAGING IN high energy ASTRONOMY

持久性有机污染物论坛2008暨第三届持久性有机污染物全...

作者： Hongliang Jia~1 Yi-Fan Li~(1,2*) Meng Yang~1 Dagao Wang~1 Daoji Cai~3 Diandou Xu~4 (1 International Joint Research Center for Persistent Toxic Substances (ijrc-pts),Dalian Maritime University,china 2 Science and Technology Branch,Environment Canada 3 Nanjing institute of Environmental Science,Nanjing,china 4 ijrc-pts,institute of high energy physics,chinese academy of sciences,china

＜正＞*** Endosulfan is persistent in the environment,and its isomers can transport through air from one place to *** concentrations of endosulfan,as the total of α-endosulfan,β-endosulfan and endosulfan sulfate,hav...

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来源： cnki会议评论

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空间科学学报 1998年第S1期18卷 12-20页

作者： LI Ti-pei (institute of high Enerpy physics, The chinese academy of sciences, Beijing 100039)

Space research is usually costly, and this restricts participation of developing countries. With traditional techniques one must construct high resolution instrument,more and more complicated and expensive, to obtain high resolution results from space observations. It is a difficult task to make observations with both high sensitivity and high resolution. Applying advanced inversion technique, one can subtract more information from old data in public domain,and, furthermore, conduct high sensitive and high-resolution experiments with low-cost low-resolution instruments. So developing and applying data analysis technique is of great importance for developing countries to do basic space *** this paper we summarize efforts of chinese scientists in recent years along this direction on imaging in space high energy astronomy.

关键词： Space astronomy Astronomical satellite Imaging

Studies on BEPC upgrade from pretzel to double-ring

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 2084-2089页

作者： ZHANG Chuang institute of high energy physics,chinese academy of sciences,Beijing 100049,china institute of high energy physics Chinese Academy of Sciences Beijing China

physics opportunity in the charm and τ energy region calls for higher luminosity of the Beijing Electron-Positron Collider (BEPC).The BEPC has experienced continuous improvement since its completion in ***,as a major upgrading project of the BEPC,aims at enhancing its luminosity of factor 30–100,following the principle of "one machine,two purposes" as adopted in BEPC,so that both high energy physics and synchrotron radiation experiments can be carried out with *** the BEPC to BEPCII,the double-ring scheme with multi-bunch e +-e-collision in the large crossing angle was studied in comparison with the single-ring pretzel *** the dedicated synchrotron radiation operation,artful "bridges" are designed to connect two halves of the outer ring in both the southern and the northern crossing *** paper reviews the studies on the BEPC upgrade from pretzel to double-ring structure of BEPCII.

关键词： collider storage ring high energy physics synchrotron radiation

Recent Beijing Spectroscopy (BES) results

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Science china(physics,Mechanics & Astronomy) 2008年第6期51卷 567-576页

作者： LI WeiGuo institute of high energy physics, chinese academy of sciences, Beijing 100049, china institute of high energy physics Chinese Academy of Sciences Beijing China

Recent experimental results from Beijing Spectroscopy (BES) are reviewed, in-cluding the hadron spectroscopy from J/ψ decays, and a number of new states are found or confirmed, including σ, κ, X(1835), ω■ threshold enhancement in J/ψ→γω■ , a broad resonance in J/ψ→K +K ■π 0, decay studies of ψ (2S) and χCJ, as well as the results of ψ (3770) non-DD decays. The current status of BEPCII/BESIII, the major upgrade of BEPC/BESII, is also reported.

关键词： Beijing Spectroscopy hadron spectroscopy charm physics BEPCII

high-nitrogen and low-irradiance can restrict energy utilization in photosynthesis of successional tree species in low subtropical forest

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Science china(Life sciences) 2008年第7期51卷 592-603页

作者： CAI Xi’An,SUN GuChou,ZHAO Ping &LIU XiaoJing South china institute of Botany,chinese academy of sciences,Guangzhou 510650,china South china institute of Botany Chinese Academy of Sciences Guangzhou China

Responses of photosynthesis and the partition of energy utilization to high-nitrogen importation and high-light intensity in leaves of three dominant tree species of subtropical forest,including sun plant or early-successional species Schima superba,mesophyte or intermediate-successional species Canstanopsis hystrix,and shading-tolerant plant or late-successional species Cryptocarya concinna were studied by using the CO2 exchange system and chlorophyll fluorescence *** results showed that,regardless of plant species,net photosynthetic rate(Pn)was higher in high-nitrogen supply and high irradiance(HNHL)plants than in low-nitrogen supply and high irradiance(LNHL)plants,implying that low-nitrogen importation would limit Pn of plants grown under high ***, high-nitrogen supply and low irradiance(HNLL)plants had a lower *** change of quantum yield(Fv′/Fm′)in opened PS II was found in leaves of HNHL,LNHL or HNLL plants of *** and C. hystrix,while a higher Fv′/Fm′occurred in HNHL plants of *** in comparison with LNHL or HNLL *** HNHL plants of *** also had a higher photochemical quantum yield(△F/Fm′) than LNHL or HNLL plants,however no similar responses were found in plants of *** and C. hystrix(Penergy consumed by photochemistry(φ PSII )was 18.2%in LNHL plants of *** which was higher than that in HNHL plants(P>0.05)and it was significantly higher than in HNLL plants(Phigher heat dissipation in light,and this effect was more severe in *** than in *** or *** results may mean that high-nitrogen importation by nitrogen deposit and low irradiance caused by changing climate or air pollution would more severely restrict photosynthetic processes in the late-succ

关键词： low subtropical forest successional plant high nitrogen concentration partition of photosynthetic energy

Effects of cosmological constant on motion of UHECR particles

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Science china(physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe institute of high energy physics, chinese academy of sciences, Beijing 100039, china Graduate School of chinese academy of sciences, Beijing 100039, china institute of high energy physics Chinese Academy of Sciences Beijing 100039 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant ∧ (＞ 0).Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented *** solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

Geochemical characteristics of rare earth elements in Wuhan section of the Yangtze River

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Journal of Environmental sciences 1995年第1期7卷 44-51页

作者： Wang Lijun Zhang Shen Zhang Chaosheng(institute of Geography,chinese academy of sciences,Beijing 100101,china)Li Xiuxia(institute of high energy physics,chinese academy of sciences,Beijing 100080,china) Inst of Geog Chinese Academy of Sciences Beijing China China

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关键词： geochemical characteristics rare earth elements Yangtze River

DEGRADATION DUE TO energy PULSE IN high-energy ZnO VARISTORS

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Journal of Central South University 1997年第2期9卷 113-116页

作者： Zhang Shugao Huang Baiyun Fang Xunhua (Powder Metallurgy Research institute, Central South University of Technology, Changsha 410083, china)Ji Youzhang (institute of Plasma physics, chinese academy of sciences, Hefei 230031, china) Powder Metallurgy Research institute Central South University of Technology Changsha 410083 China institute of Plasma physics Chinese Academy of Sciences Hefei 230031 China

The degradation phenomena due to the energy pulse in the high-energy ZnO varistors used for deexitation and overvoltage protection of hydroelectric generator are investigated. The energy pulse, obtained by releasing the energy stored in an inductor, can be equivalent to the combination of the DC field components and the energy component. The variations of the characterized voltages, nonlinear coefficients and pre-breakdown V-A characteristics, increase with the number of the applied energy pulse. The asymmetrical variations of the electric properties of the high-energy ZnO varistors after the energy pulse arise from the deformation of the double Schottky barriers due to the ion migration occuring in the depletion layer and in the grain boundary.

关键词： high-energy ZnO varistors energy pulse degradation V-A characteristics grain boundary barrier ion migration

Correlations Between the Conditional Moments in ^(16)O and ^(32)S Fragmentation at high energy

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chinese journal of nuclear physics 1995年第1期17卷 13-16页

作者： Liu Fu-hu (institute of high energy physics,chinese academy of sciences,Beijing 100039)Sun Han-cheng (china institute of Atomic energy,B.O.Box 275(94),Beijing 102413) 中科院高能物理所北京中国原子能科学院北京

The conditional moments of the charge distributions of the projectile frag-ments in 16O and 32S fragmentation behaviour are obtained by using a partition *** logarithmic correlations between the conditional moments are observed,Thecalculated results are in agreement with the experimental data of 3.7 and 200GeV N 16O-emulsion and 200 GeV/N 32S-emulsion interactions.

关键词： Projectile fragment Charge distribution Conditional moment Logarithmic correlation