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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3.& WANG Huijun2.1. Nansen-Zhu International Research center, {3. of Atmospheric {2., Chinese Academy of Sciences, {3. 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the Chinese Academy of Sciences, {3. 100049, china Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the Chinese Academy of Sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Strong decays of N~*(153.) in an extended chiral quark model

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2.3.& ZOU BingSong1,2.3.1 institute of High Energy {3.,Chinese Academy of Sciences,{2. 100049,china 2.Theoretical {3. center for Science Facilities,Chinese Academy of Sciences,{2. 100049,china 3.Graduate University of Chinese Academy of Sciences,{2. 100049,china institute of High Energy physics Chinese Academy of Sciences Beijing China Theoretical physics center for Science Facilities Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

FINITE DIFFERENCE METHOD WITH NONUNIFORM MESHES FOR QUASILINEAR PARABOLIC SYSTEMS

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Journal of Computational Mathematics 1997年第4期15卷 289-310页

作者： Yu-lin Zhou (Labomtory of Computational physics, center of Nonlinear Studies, {2. of Applied physics and Computational Mathematics, beijing, china) 北京应用物理和计算数学所北京

The analysis of the finite difference schemes with nonuniform meshes for the problems of partial differential equations is extremely rare even for very simple problems and even for the method of fully heuristic character. In the present work the boundary value problem for quasilinear parabolic system is solved by the finite difference method with nonuniform meshes. By using of the interpolation formulas for the spaces of discrete functions with unequal meshsteps and the method of a priori estimation for the discrete solutions of finite difference schemes with nonuniform meshes, the absolute and relative convergence of the discrete solutions of the finite defference scheme are proved. The limiting vector function is just the unique generalized solution of the original problem for the parabolic system.

关键词： Boundary value problems Convergence of numerical methods Estimation Heuristic methods Interpolation Partial differential equations

High-pressure and high-tem-perature synthesis of MgB_2.and its superconductivity

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Chinese Science Bulletin 2001年第22期46卷 1932-1934页

作者： ZHU Jialin, LI Shaochun, YU Richeng, LI Fengying LIU Zhengxing & JIN ChangqingLaboratory for Extreme Condition physics, institute of physics, {2. for{3. matter Physcis and beijing High Pressure Research {2., Chinese Academy of Sciences, beijing 100080, china Laboratory for Extreme Condition physics Institute of Physics Center for Condensed Matter Physcis and Beijing High Pressure Research Center Chinese Academy of Sciences Beijing China

The single-phase sample of MgB2.was prepared successfully at the temperature of 900℃ and under the pressure of 3.GPa. The structure of the sample was investigated using powder X-ray diffraction and Rietveld analysis. The results show that the structure of the sample belongs to the hexagonal structure with space group of P6/mmm, a=3.0861(5) A, c=3.52.2.8) A. The magnetic and resistance measurements indicate that the superconducting transition temperature Tc is 3. K.

关键词： superconductivity magnetization resistance.

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3.& ZHANG XiaoZhong4,5 1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, institute of Low Energy Nuclear physics, {2. Normal University, {2. 100875, china 2.{2. Radiation center, {2. 100875, china 3.Laboratory of Optical physics, institute of physics, Chinese Academy of Sciences,{13., china 4 Key Laboratory of Advanced Materials of the Ministry of Education, Department of Materials Science and Engineering, Tsinghua University, {2. 100084, china 5 {2. National center for Electron Microscopy, Tsinghua University, {2. 100084, china Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation center Beijing China Laboratory of Optical physics Institute of Physics Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China beijing National center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-xTexO3.δ (x=0.1, 0.2. 0.3. were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3. ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3. and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3. is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3. is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

PHASE EXTENSION AND STRUCTURE ANALYSIS BY THE MAXIMUM ENTROPY METHOD

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Acta Metallurgica Sinica(English Letters) 1998年第4期11卷 241-254页

作者： G.B.Hu and Q.B.Yang (Department of physics, Xiangtan University, Xiangtan 411105, china)({2. Laboratory of Electron Microscopy,{3. for condensed matter physics, The Chinese Academy of Sciences, P. O. Box 2.2., beijing 100080, china) Xiangtan Univ Xiangtan China

Excellent results are obtained in structure analysis with jew phases of structure factors by the maximum-entropy method (MEM) for CaGaN PbCO3.and ReBe2. single crystals. The computation time and memory space are minim... 详细信息

关键词： maximum entropy method structure analysis phase extension,symmetry

New evidence for lack of CMB power on large scales

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2.3.1 Key Laboratory of Particle Astrophysics, institute of High Energy physics, Chinese Academy of Sciences, {3. 100049, china 2.Department of physics & center for Astrophysics, Tsinghua University, {3. 100084, china 3.Department of Engineering physics & center for Astrophysics, Tsinghua University, {3. 100084, china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of physics & center for Astrophysics Tsinghua University Beijing China Department of Engineering physics & center for Astrophysics Tsinghua University Beijing China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china(physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3.4, JIANG YunGuo1 & LI XinGuo2.3.1 institute of Theoretical physics, College of Applied Sciences, {2. University of Technology, {2. 10002., china 2.institute of Modern physics, Chinese Academy of Sciences, Lanzhou 73.000, china 3.center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Collisions, Chinese Academy of Sciences, Lanzhou 73.000, china 4 china center of Advanced Science and Technology (World Laboratory), beijing 100080, china institute of Theoretical physics College of Applied Sciences Beijing University of Technology Beijing China center of Theoretical Nuclear physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou China china center of Advanced Science and Technology (World Laboratory) Beijing China institute of Modern physics Chinese Academy of Sciences Lanzhou China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Interference pattern generation and simulation in the single beam of a white light continuum

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1060-1064页

作者： YU ZhiHao & WENG YuXiang Laboratory of Soft matter physics,{2. of physics,Chinese Academy of Sciences,and National Laboratory of condensed matter physics,beijing 100190,china Laboratory of Soft matter physics Institute of Physics Chinese Academy of Sciences and National Laboratory of Condensed Matter Physics Beijing China

We demonstrate the interference phenomenon in the White Light Continuum(WLC) generated by a single femtosecond laser beam. Different kinds of spatial interference patterns of the WLC generation under various conditions were investigated. The spatial patterns were attributed to interference between the filaments in the WLC generated by the fundamental laser beam yielding the diffraction effect from spatial confinement. Simulations of different patterns were performed. By comparing the results of simulation with those of experiments,the distances of several micrometers between the neighboring filaments can be derived,which agree with the literature values from direct measurements.

关键词： interference supercontinuum generation ultrafast nonlinear optics