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Brownian ratchets driven by flashing noise strength

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Chinese Science Bulletin 1999年第21期44卷 1956-1961页

作者： ZHAO Tongjun, ZHAN Yong, ZHUO Yizhong and WU XizhenDepartment of Applied Mathematics and Physics , Hebei University of Technology , Tianjin 300130, china china institute of atomic {4., beijing 102.1., china institute of Theoretical Physics, Chinese Academy of Sciences , beijing 100080, china Corresponding author Dept. of Appl. Math. and Physics Hebei University of Technology Tianjin 300130 China china institute of atomic energy Beijing 102413 China institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

The stochastic transport driven by flashing multi-noise sources in a ratchet is studied. The stationary current versus the noise strength and the colored noise correlated time T is obtained . At a fixed flip rate and strength of the colored noises, the novel phenomenon of the current reversal occurs as T reaches a certain value. More than one reversal point exists when

关键词： flashing force ratchet current reversal Langevian equation.

Approximation analytical solutions for a unified plasma sheath model by double decomposition method

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Nuclear Science and Techniques 1998年第4期9卷 193-197页

作者： Fang Jin-Qing (china institute of atomic energy{4.)

A anified plasma sheath model and its potential equation are proposed. Any higher-ordor-approximation analytical solutions for the unified plasma sheath potential equa tiop are derived by double decomposition method.

关键词：等离子体屏蔽模型双分解方法近似分析

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 10004.,china 1. institute of High energy Physics Chinese Academy of Sciences Beijing 100049 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

Track Fading and Its Applications in Archaeology, Tectonics and Geothermal Chronology in china

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Journal of Earth Science 2013年第4期24卷 645-651页

作者：郭士伦袁万明陈宝流黄慰文刘顺生 Department of Nuclear Physics China Institute of Atomic Energy School of Earth Sciences and Resourses China University of Geosciences Department of Radioisotopes China Institute of Atomic Energy institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Guangzhou institute of Geochemistry Chinese Academy of Sciences

Track fading is a basic phenomenon in track science and has been the source of informa- tion in geosciences. This article summarizes the knowledge of track fading and gives some examples of successful applications of track fading in archaeology, tectonics and geothermal chronology in china. The applications of track fading are classified into 5 modes：（1） mode of complete fading （annealing）; （2） mode of partial fading; （3） use of the dependence of track fading on time and temperature; （4. use of the differences of track fading between coexisting minerals; and （5） use of fading-reduced track length. Track fading mechanisms hints that scientists in geothermal chronology should adopt microprobes for quantitative elemental analysis to determine the detailed chemical compositions of each mineral grain or at least of the grains from each position of geological structures in order that one becomes well aware of the relation between the track fading behavior and chemical compositions of the mineral used.

关键词： track fading archaeology tectonics geothermal chronology.

GHG emission reductions and costs to achieve Kyoto target

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Journal of Environmental Sciences 2003年第4期15卷 541-547页

作者： CHEN Wen\|ying (energy, Environment and Economy Research institute, Tsinghua University, beijing 100084. china.) energy Environment and Economy Research Institute Tsinghua University 北京 100084

Emission projection and marginal abatement cost curves(MACs) are the central components of any assessment of future carbon market, such as CDM (clean development mechanism) potentials, carbon quota price etc. However, they are products of very complex, dynamic systems driven by forces like population growth, economic development, resource endowments, technology progress and so on. The modeling approaches for emission projection and MACs evaluation were summarized, and some major models and their results were compared. Accordingly, reduction and cost requirements to achieve the Kyoto target were estimated. It is concluded that Annex I Parties' total reduction requirements range from 503—1304.MtC with USA participation and decrease significantly to 14.—612 MtC after USA's withdrawal. Total costs vary from 21—77 BUSD with USA and from 5—36 BUSD without USA if only domestic reduction actions are taken. The costs would sharply reduce while considering the three flexible mechanisms defined in the Kyoto Protocol with domestic actions' share in the all mitigation strategies drops to only 0—16%.

关键词： Kyoto Protocol emission reduction abatement cost flexible mechanisms

Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing Normal University, beijing 100875, china 2. Physics Department, beijing Normal University, beijing 100875, china 3. china institute of atomic energy, beijing 102.1., china Key Laboratory of Beam Technology Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics Department Beijing Normal University Beijing 100875 China china institute of atomic energy Beijing 102413 China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 24.Cm(26Mg,4.)270Hs, 24.Pu(30Si,4.)270Hs, 238U(36S,4.)270Hs and 226Ra(4.Ca,4.)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(4.Ca,4.)270Hs and 238U(36S,4.)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

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 10004., china 1. institute of High energy Physics Chinese Academy of Sciences Beijing 100049 China

Recent experimental results from beijing Spectroscopy (BES) are reviewed, including the hadron spectroscopy from J/ψ decays, and a number of new states are found or confirmed, including σ, κ, X(1835), ωφ threshold enhancement in J/ψ→γωφ, a broad resonance in J/ψ→K + K ? π 0, decay studies of ψ(2S) and χ CJ , as well as the results of ψ(3770) non-D $ \bar D $ 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

Properties of the 3/2^-[521] band in the odd-N rare-earth nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3 & ZHU LiHua4.1institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, china 2Graduate University of Chinese Academy of Sciences, beijing 10004., china 3State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, beijing 100871, china 4.6} institute of atomic energy, beijing 102.1., china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China4. China Institute of Atomic Energy Beijing 102413 China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[64.], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3/2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

Integrated Numerical Experiment of an Intense RF Linac for CIAE Far-Infrared FEL

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Chinese journal of nuclear physics 1997年第2期19卷 121-127页

作者： Fu Shinian Chen Yinbao Huang Zhibin china institute of atomic energy,P.O.Box 275(17),{4. 102.1. 中国原子能科学院北京

An L band RF linac is now under installation at CIAE to provide intense electronbeam for a far-infrared free-electron laser *** linac consists of a DC thermionicgun,a subharmonic prebuncher,a buncher,an accelerating section and a beam transport *** the INEX(Integrated Numerical Experiment)conducted for prediction of the perfor-mance of the complex and the comparison of some of the simulation results with available ex-perimental data,it shows that the beam quality can satisfy our FEL requirements.

关键词： RF linac Free electron laser Integrated numerical experiments