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Design of a new dynamical core for global atmospheric models based on some efficient numerical methods

Science china Mathematics 2004年第z1期47卷 4-21页

作者： WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU Hongtaostate key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric physics, Chinese Academy of Sciences, beijing 100029, china Department of Computational Mathematics, Academy of Mathematics and System Sciences, peking university, beijing 100871, china Chinese Acad Sci Inst Atmospher Phys State Key Lab Numer Modeling Atmospher Sci & Geop Beijing 100029 Peoples R China peking Univ Acad Math & Syst Sci Dept Computat Math Beijing 100871 Peoples R China

A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community Atmospheric Model Version 2 (CAM2) of NationalCenter for Atmospheric Research (NCAR), are included.

关键词： dynamical core, equal-area mesh, anti-symmetry, effective energy conservation.

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Micro-mechanical analysis of dynamic processes of nanomanipulation

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Science china(physics,Mechanics & Astronomy) 2004年第z1期47卷 88-92页

作者： HU Jie, ZHANG Yujun, LI Peng, WANG Hui, HUANG Lan & HU Yuanzhongstate key laboratory of Tribology, Tsinghua university, beijing 100084, china Department of physics, Tsinghua university, beijing 100084, china College of Chemistry and Molecular Engineering, peking university, beijing 100871, china 1. state key laboratory of Tribology Tsinghua University 100084 Beijing China 2. Department of physics Tsinghua University 100084 Beijing China 3. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China

In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed from the perspective of micro-mechanics. It is found that differences in surface conditions can lead to obvious increase in micro-friction between nanotube and substrate. And also due to rehybridization, carbon nanotubes present excellent resilience when undergoing different degrees of strain. Finally, carbon nanotubes can complexly deform from elastic stage to plastic stage before complete rupture.

关键词： nanomanipulation, carbon nanotubes, AFM tips, micro-mechanics.

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Electronic structure and magnetism of R(Fe,Si)_(12) (R=Y,Nd)

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2, FAN Zhijian1, GAO Tao3 & QI Xinhua31. Institute of nuclear physics and Chemistry, china Academy of Engineering physics, Mianyang 621900, china 2. Department of physics, peking university, beijing 100871, china 3. Institute of Atomic and Molecular physics, Sichuan university, Chengdu 610065, china 1. Institute of nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. Department of physics Peking university Beijing 100871 China 3. Institute of Atomic and Molecular physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

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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 730000,china 6 Center of Theoretical nuclear physics,National laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,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 35 80 Br + 82 208 Pb → 117 288 X are also calculated and discussed.

关键词： superheavy nuclei transport theory shell effect cross sections

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Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1 & TAN Wenchang2 1. Institute of Applied Mathematics, School of Math & System Science, Shandong university, Jinan 250100, china 2. state key laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering Science, peking university, beijing 100871, china 1. Institute of Applied Mathematics School of Math & System Science Shandong University Jinan 250100 China 2. state key laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering Science Peking University Beijing 100871 China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

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Propagation of interplanetary shock excited ultra low frequency (ULF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

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Science china(Technological Sciences) 2010年第9期53卷 2528-2534页

作者： WANG ChengRui1,2,ZONG QiuGang1,3 & WANG YongFu1 1 Institute of Space physics and Applied technology,peking university,beijing 100871,china 2 Sate key laboratory of Space Weather,Chinese Academy of Sciences,beijing 100190,china 3 Center for Atmospheric Research,600 Suffolk Street,university of Massachusetts Lowell,MA 01854,USA 1. Institute of Space physics and Applied technology Peking University Beijing 100871 China2. Sate Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Center for Atmospheric Research University of Massachusetts 600 Suffolk Street Lowell MA 01854 USA

The ultra low frequency (ULF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the ULF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the ULF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the ULF *** a comparison with recent observations,we found that: in the event during November 7,2004 that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the ULF waves and changed into geomagnetic *** result reveals that the ULF wave is in contact with the ground geomagnetic *** ULF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between CLUSTER multi-satellite observation and geomagnetic station observation is due to the ULF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (ULF) wave magnetic storm ionosphere IRI model interplanetary shock

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Structure and optical properties of the Ge and Sn quantum-dots

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nuclear Science and Techniques 2000年第2期11卷 119-123页

作者： HAN Zhao-Hui ZHAO Zi-Qiang(Institute of Heavy Ion physics, Technical physics Depariment, peking university,beijing 100871) 北京大学北京 100871

Embedded cluster samples Ge:CaF2 and Sn:CaF2 with different sizes less than 8nm were produced and their optical properties were *** diffraction reveals that the clusters’ structures are crystallites and compared with the bulk Germanium and Stannum, lattice constants expand about 4.7% in the case of Ge:CaF2 and 5.2% of Sn:CaF2. Optical absorption and photoluminescence spectra of these samples show good agreement with the Quantum-Confinement-Effect(QCE) theory. With the decreasing of the cluster’s size, the energy gap broadens and the absorption edge blueshift is observed, and the absorption edge also shifts with the changing of the fraction of Sn and Ge. The XPS results show that in the cluster state,the binding energy becomes higher.

关键词：锗微晶锡微晶半导体 X射线光电子能谱结构光学性质电子衍射氟化钙

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Quasi-secure quantum dialogue using single photons

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2 & WEN QiaoYan31 College of Computer Science and technology, beijing university of technology, beijing 100022, china 2 state key laboratory of Information Security, Graduate university of the Chinese Academy of Sciences, beijing 100049, china 3 School of Science, beijing university of Posts and Telecommunications, beijing 100876, china College of Computer Science technology Beijing University of Technology Beijing 100022 China state key laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

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Heterogeneous reaction of NO_2 with sea salt particles

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Science china Chemistry 2010年第12期53卷 2652-2656页

作者： YE ChunXiang 1,LI HongJun 1,ZHU Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 state key Joint laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,peking university,beijing 100871,china 2 College of Atmospheric physics,Nanjing university of Information Science and technology,Nanjing 210044,china 1. state key Joint laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China2. College of Atmospheric Physics Nanjing University of Information Science and Technology Nanjing 210044 China

To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/*** results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

关键词： sea salt particles diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) hydrated water absorbed water reactive uptake coefficient

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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5 1. key laboratory For Quantum Information and Measurements of MOE, Department of physics, Tsinghua university, beijing 100084,china 2. Department of Materials Science and Engineering, beijing Normal university, beijing 100875, china 3. Testing and Analytical Center, beijing Normal university, beijing 100875,china 4. Department of physics, beijing Normal university, beijing 100875, china 5. key laboratory For atomic and Molecular Nanosciences, Tsinghua university, beijing 100084,china 1. key laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. Department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. Department of physics Beijing Normal University 100875 Beijing China 5. key laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

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