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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, 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

Recycled graphite for more sustainable lithium-ion batteries

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Carbon energy 2024年第5期6卷 15-24页

作者： Mayokun Olutogun Anna Vanderbruggen Christoph Frey Martin Rudolph Dominic Bresser Stefano Passerini Helmholtz institute Ulm(HIU) Ulm Germany Karlsruhe institute of Technology(KIT) KarlsruheGermany Helmholtz Zentrum Dresden-Rossendorf(HZDR) Helmholtz Institute Freiberg for Resource Technology(HIF)FreibergGermany ProGraphite GmbH UntergriesbachGermany Chemistry Department Sapienza University of RomeRomeItaly

The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the *** great success,however,urgently calls for the efficient recycling of LIBs at the end of their ***,we describe a froth flotation-based process to recycle graphite—the predominant active material for the negative electrode—from spent LIBs and investigate its reuse in newly assembled *** has been found that the structure and morphology of the recycled graphite are essentially unchanged compared to pristine commercial anode-grade graphite,and despite some minor impurities from the recycling process,the recycled graphite provides a remarkable reversible specific capacity of more than 350 mAh g^(−1).Even more importantly,newly assembled graphite‖NMC532 cells show excellent cycling stability with a capacity retention of 80%after 1000 cycles,that is,comparable to the performance of reference full cells comprising pristine commercial graphite.

关键词： anode graphite lithium-ion battery recycling sustainability

ABUNDANCE PATTERNS OF REFRACTORY SIDEROPHILE ELEMENTS OF FE-NI METALLIC GRAINS IN C3V CHONDRITES

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Science in China,Ser.B 1986年第3期29卷 326-336页

作者：柴之芳 institute of High energy physics Academia Sinica Beijing

A lot of Fe-Ni metallic grgins in the inclusions from the Allende and Leoville chondrites were studied on the concentration patterns of some refractory siderophile elements, Os, Ir, Ru, Re, W, Mo and Pt, using neutron activation analysis. Our experimental results show that the grains studied in this work can be roughly classified into two types: equilibrium and non-equilibrium grains. This probably reflects their distinction in the fractionation and condensation processes of the solar system. Or the so-called non-equilibrium grains might be the relics from the supernovae *** experiments were carried out on microgram level.

关键词： Ru ABUNDANCE PATTERNS OF REFRACTORY SIDEROPHILE ELEMENTS OF FE-NI METALLIC GRAINS IN C3V CHONDRITES Re Pt ppm work SRM

Timing in the Time Domain: Cygnus X-1

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Chinese Journal of Astronomy and Astrophysics 2001年第4期1卷 313-332页

作者： Ti-Pei Li (Department of physics and Center for Astrophysics, Tsinghua University, Beijing 100084 High energy Astrophysics Lab., institute of High energy physics, Chinese Academy of Sciences, Beijing 100039)E-mail:litp@*** Department of physics and Center for Astrophysics Tsinghua University Beijing 100084 High Energy Astrophysics Lab. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039

Quantities characterizing temporal property, e.g., power density, coherence, and time lag, can be defined and calculated directly in the time domain without using the Fourier transformation. Spectral hardness, variability duration, and correlation between different characteristic quamtities on different time scale can be studied in the time domain as well. The temporal analysis technique in the time domain is a powerful tool, particularly in studying rapid variability on short time scales (or in high frequencies). Results of studying variabilities of X-rays from Cyg X-1 with the analysis technique in the time domain and RXTE data reveal valuable clues to understanding production and propagation processes of X-rays and structure of accretion disk in the black hole system.

关键词： methods: data analysis - stars: individual (Cygnus X-1) - X-rays: stars

Characterization of microarc oxidation coatings on pure titanium

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Rare Metals 2003年第1期22卷 42-48页

作者： XUE Wenbin, WANG Chao, Li Yongliang, and CHEN RuyiKey Laboratory for Beam Technology and Materials Modification, institute of Low energy Nuclear physics, Beijing Normal University, Beijing 100875, China 北京师范大学射线束技术与材料改性教育部重点实验室北京 100875

Key Laboratory for Beam Technology and Materials Modification, institute ofLow energy Nuclear physics, Beijing Normal UniversityThe morphology, composition, and phase structure of the oxide coatings produced on the surface ofpure titanium by alternating-current microarc discharge in aluminate solution were investigated byX-ray diffraction and scanning electron microscopy. The profiles of the hardness H and the elasticmodulus E in the coatings were determined using a nanoindentation method. The concentrationdistributions of Ti, Al, and O in the coating show that this coating over 30 mu m thick contains twolayers: an outer layer and an inner layer. The oxide coating is mainly composed of TiO_2 rutile andAl_2TiO_5 compounds. During oxidation, the temperature in the microarc discharge channel was veryhigh to make the local coating molten. From the surface to the interior of the coating, H and Eincrease gradually, and then reach maximum values of 9.78 GPa and 176 GPa respectively at a distanceof 7 mu m from the coating/titanium interface. They are also rather high near the interface.

关键词： pure titanium ceramic coating microarc oxidation microstructure nanoindentation

A MULTIGRID METHOD FOR NONLINEAR PARABOLIC PROBLEMS

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Journal of Computational Mathematics 1996年第4期14卷 363-382页

作者： x.J. Yu(Laborutory of Computational physics, institute of Applied physics and ComputationalMathematics, Beijing, China) Laboratory of Computational physics Institute of Applied Physics and Computational Mathematics Beijing China

The multigrid algorithm in [13] is developed for solving nonlinear parabolic equations arising from the finite element discretization. The computational cost of the algorithm is approximate O(NkN) where N-k is the dim... 详细信息

关键词： Th Math A MULTIGRID METHOD FOR NONLINEAR PARABOLIC PROBLEMS UC

Transport　of　atmospheric　trace　elements　and　dust－soil　to　the　Western　Pacific　Ocean

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Journal of Environmental Sciences 1996年第4期8卷 460-465页

作者： Yang Shaojin Chen Bingru Yang Yinan(institute of High energy physics,Chinese Academy of Sciences,Beijing 100080,China) institute of High energy physics Chinese Academy of Sciences Beijing 100080 China

Atmospheric aerosol and rainwater samples collected in the different Western Pacific area were analyzed by instrumental neutron activation and proton induced X-ray emission to (1) determine the atmospheric concentrations of trace elements over the Western Pacific and (2) to esti mate the atmospheric deposition of trace elements and dust-soil material to this region. High abundance of pollutant and crustal elements relative to oceanic sources was observed. Some characteristics of marine atmosphere relating to long-range transport of crustal and anthropogenic elements from continent to the remote ocean are discussed. The total dust-soil particle mass is estimated to be 0. 066-1.2 μg/m￣3 over the Western Pacific Ocean areas. Atmospheric inputs of dust-soil particles control the marine particle concentrations of crustal elements. In addition, the characteristics of marine rain water are discussed.

关键词： dust-soil marine rain-water atmospheric trace elements.

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