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Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2 1 Department of Physics, China university of Petroleum, Dongying 257061, China 2 Department of Physics, beijing normal university, beijing 100875, China Department of Physics China University of Petroleum Dongying 257061 China Department of Physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Problems in wavelet analysis of hydrologic series and some suggestions on improvement

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Progress in Natural science:Materials International 2007年第1期17卷 80-86页

作者： WANG Hongrui, YE Letian, LIU Changming, YANG Chi and LIU Peng ( college of Water sciences, beijing normal university,{3., China Key Laboratory for Water and Sediment sciences, Ministry of Education,{3., China School of Mathematical sciences, Peking university, beijing 100089, China college of Engineering sciences, university of Region, Canada) [a]college of Water sciences Beijing Normal University Beijing China [b]Key Laboratory for Water and Sediment sciences Ministry of Education Beijing China [c]School of Mathematical sciences Peking University Beijing China [d]college of Engineering sciences University of Region Canada

Applying the wavelet theory and methods to investigate the hydrologic processes such as precipitation and runoff is a hot field. However, several aspects in research are usually ignored: the effect of admissible condition of wavelet functions and the disturbance of noises for the detection of periods, the effect of the length of a hydrologic time-series on the final result, and the choice between the anomaly and the original time series for wavelet analysis. In this paper, these issues are fully discussed. Precipitation data from Lanzhou Precipitation Station are taken for case study. The result indicates that in the wavelet analysis of hydrologic series, denoise methods should be used to eliminate the influence of noises. The MexHat wavelet function satisfies the admissible condition, which ensures that the periodic properties of hydrologic processes can be well represented by using the MexHat wavelet for decomposition. The affected range of hydro-logic series which should be discarded before analysis is given. It is also suggested that the anomaly series should be used to highlight the actual undulation of the hydrologic series.

关键词： wavelet analysis hydrologic process admissible condition noise period.

Shell effect and capture cross sections in the synthesis of superheavy nuclei

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science China(Physics,Mechanics & Astronomy) 2009年第10期52卷 1489-1493页

作者： DU SaiSai1,2,BIAN BaoAn1,2,3.LIU Min1,2,4,FENG ZhaoQing5,6 & ZHANG FengShou1,2,6 1 Key Laboratory of Beam technology and Material Modification of Ministry of Education,college of Nuclear science and technology,beijing normal university,beijing 100875,China 2 beijing Radiation Center,beijing 100875,China 3.School of science,Jiangnan university,Wuxi 214122,China 4 college of Physics and technology,Guangxi normal university,Guilin 541004,China 5 Institute of Modern Physics,Chinese Academy of sciences,Lanzhou 73.000,China 6 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,China Key Laboratory of Beam technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China School of science Jiangnan University Wuxi 214122 China college of Physics and technology Guangxi Normal University Guilin 541004 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The shell effect is included in the improved isospin dependent quantum molecular dynamics model in which the shell correction energy of the system is calculated by using the deformed two-center shell model. A switch function is introduced to connect the shell correction energy of the projectile and the target with that of the compound nucleus during the dynamical fusion process. It is found that the calculated capture cross sections reproduce the experimental data quantitatively at the energy near the Coulomb barrier. The capture cross sections for reaction 3. 80 Br + 82 208 Pb → 117 288 X are also calculated and discussed.

关键词： superheavy nuclei transport theory shell effect cross sections

A multi-dimensional microcanonical Monte Carlo study of S_0→T_1 intersystem crossing of isocyanic acid

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science China Chemistry 2009年第11期52卷 1885-1891页

作者： ZHANG Feng1,2,FANG WeiHai1,LUO Yi2 & LIU RuoZhuang1 1 college of Chemistry,beijing normal {3.,beijing 100875,China 2 Theoretical Chemistry,School of Biotechnology,Royal Institute of technology,S-10691 Stockholm,Sweden 1. college of Chemistry Beijing Normal University Beijing 100875 China 2. Theoretical Chemistry School of Biotechnology Royal Institute of Technology S-10691 Stockholm Sweden

A general formula for the multi-dimensional Monte Carlo microcanonical nonadiabatic rate constant expressed in configuration space is applied to calculate the rate of intersystem crossing(ISC) between the ground(S0) and first excited triplet(T1) states for isocyanic ***-,two-and three-dimensional potential energy surfaces are constructed by coupled-cluster single-double CCSD calculations,which are used for Monte Carlo *** calculated S0→T1 ISC rate is in good agreement with experimental findings,which gives us a reason to believe that the multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory is a very effective method for calculating nonadiabatic transition rate of a polyatomic molecule.

关键词： multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory intersystem crossing isocyanic acid nonadiabatic transition

Quenched moderate deviations principle for random walk in random environment

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science China Mathematics 2010年第8期53卷 1947-1956页

作者： HONG WenMing 1 & WANG HuaMing 1,2 1 Key Laboratory of Mathematics and Complex Systems of Ministry of Education & School of Mathematical sciences,beijing normal {3.,beijing 100875,China 2 Department of Basic Courses,Business college,beijing Union {3.,beijing 100025,China 1. Key Laboratory of Mathematics and Complex Systems of Ministry of Education & School of Mathematical sciences Beijing Normal University Beijing 100875 China2. Department of Basic Courses Business College Beijing Union University Beijing 100025 China

We derive a quenched moderate deviations principle for the one-dimensional nearest random walk in random environment,where the environment is assumed to be stationary and *** approach is based on hitting time decompos... 详细信息

关键词： random walk in random environment moderate deviations principle hitting time

Approach to synthesis of novel chiral 3.chloro-2(5H)- furanone and its application in asymmetric reactions

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Chinese science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. Department of Chemistry, Tonghua Teacher’s college, Tonghua 13.002, China 2. Department of Chemistry, beijing normal university, beijing 100875, China Department of Chemistry Tonghua Teacher’s College Tonghua China Department of Chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3.chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13.C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3.(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3.chloro-2-(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

Weighted estimates for commutators of singular integral operators with non-doubling measures

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science China Mathematics 2007年第11期50卷 1621-1641页

作者： Guo-en HU~1 Da-chun YANG~(2+) Dong-yong YANG~2 1 Department of Applied Mathematics,university of information Engineering,Zhengzhou 450002,China 2 School of Mathematical sciences,{3. normal university,{3. 100875,China Department of Applied Mathematics University of Information Engineering Zhengzhou 450002 China School of Mathematical sciences Beijing Normal University Beijing 100875 China

Letμbe a nonnegative Radon measure on R^d which only satisfiesμ(B(x,r))≤C_0r^n for all x∈R^d,r>0,and some fixed constants C_0>0 and n∈(0,d].In this paper,some weighted weak type estimates with A_(p,(log L)~σ)~ρ(μ) weights are established for the commutators generated by Calder■n-Zygmund singular integral operators with RBMO(μ) functions.

关键词： non-doubling measure weight singular integral operator commutator

Plausible impact of global climate change on water resources in the Tarim River Basin

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science China Earth sciences 2005年第1期48卷 65-73页

作者： CHEN Yaning & XU Zongxue Xinjiang Institute of Ecology & Geography, Chinese Academy of sciences, Urumqi 83.011, China college of Environmental sciences,{3., beijing 100875, China 1. Xinjiang Institute of Ecology & Geography Chinese Academy of Sciences 830011 Urumqi China 2. college of Environmental sciences Beijing Normal University 100875 Beijing China

Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

关键词： climate change, hydrological change, temperature, precipitation, streamflow, Tarim River.

Multiparty quantum secret sharing of classical and quantum messages

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Progress in Natural science:Materials International 2007年第1期17卷 26-31页

作者： CHEN Pan, DENG Fuguo and LONG Guilu ( Key Laboratory for Quantum information and Measurements, and Department of Physics, Tsinghua university, beijing 100084, China Key Laboratory of Beam {3. and Material Modification, MOE, Institute of Low Energy Nuclear Physics, and Department of Material science and Engineering, beijing normal university, beijing 100875, China beijing Radiation Center, beijing 100875, China Key Laboratory for Atomic and Molecular Nano-sciences, Tsinghua university, beijing 100084, China) [a]Key Laboratory for Quantum information and Measurements and Department of Physics Tsinghua University Beijing China [b]Key Laboratory of Beam technology and Material Modification MOE Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing China [c]beijing Radiation Center Beijing China [d]Key Laboratory for Atomic and Molecular Nano-sciences Tsinghua University Beijing China

A scheme for multiparty quantum secret sharing of classical and quantum messages is proposed by using entanglement swapping. This scheme can distribute not only the classical information but also the quantum informati... 详细信息

关键词： quantum secret sharing classical message quantum message EPR pair.