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Some evidence of drying trend over northern china from 1951 to 2.04

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Chinese Science Bulletin 2006年第23期51卷 2913-2925页

作者： MA Zhuguo1,2.& FU Congbin1,2.1. Key Laboratory of Regional Climate-Environment for Temperate East Asia, Chinese Academy of Sciences, beijing 10002., china 2. START Regional Center for Temperate East Asia, {2. of Atmos-pheric physics, Chinese Academy of Sciences, beijing 10002., china Key Laboratory of Regional Climate-Environment for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China START Regional Center for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The surface wetness index, Palmer drought sererity index and the retrieval of soil moisture over china were calculated using monthly precipitation and monthly mean surface air temperature. Based on the contrast analysis of the variation of the above three indices and precipitation, the dry/wet spatio-temporal pattern of northern china in the last 54 years was revealed, and the evidence of drying trend over northern china was analyzed, especially. The results show the following four facts: (1) The drying trend is the main characteristic of the eastern part of Northwest china and the central part of North china since the 1980s and it was enhanced in the last 15 years mainly due to the precipitation decrease and the temperature increase; (2. During the last 54 years, there was only one dry/wet shift at the interdecadal scale occurring in the eastern part of Northwest china and the central part of North china in the late 1970s, which was related to 1977/1978 global abrupt change, whereas there were three shifts in Northeast china, one was in the mid 1990s and the other two were in 1965 and 1983, respectively; (3) Unlike the variation trend of other subregions of northern china, the western part of Northwest china is currently located in a relatively wetting period, which is weak-ened due to the temperature increase; (4) The extreme drought frequency is obviously increasing in the eastern part of Northwest china, the central part of North china and Northeast china since the 1980s, which is closely related to the precipitation decrease and temperature increase in these subregions.

关键词：中国北方干燥趋向干旱索引气候背景

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth Sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2.3 1. National Marine Environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, {2. of Atmospheric physics, Chinese Academy of Sciences, beijing 10002., china 3. Graduate University of Chinese Academy of Sciences, beijing 100049, china National Marine Environmental Forecasting Center Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

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 2.7061, china 2.Department of physics, beijing Normal University, beijing 100875, china Department of physics China University of Petroleum Dongying China Department of physics Beijing Normal University Beijing 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

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, beijing 100080, 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

Asymptotic behavior of perturbed solution for simple coupled ocean-atmosphere model for ENSO

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Chinese Science Bulletin 2003年第S2期48卷 5-8页

作者： LIN Wantao~1 & MO Jiaqi~2.1. LASG, institute of Atmospheric physics. Chinese Academy of Sciences, {2. 10002., china 2. Department of mathematics, Huzhou Normal College, Huzhou 313000. china Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Huzhou Normal Coll Dept Math Huzhou 313000 Peoples R China

The El Nio/La Nia and the Southern Oscilla-tion are an interannual phenomenon involved in the tropicalPacific Ocean-atmosphere interactions. In this paper, basedon a kind of simple coupled ocean-atmosphere model forENSO, using the perturbed theory and method, the asymp-totic behavior of solution of corresponding problem is stud-ied. It is proved from the results that the trajectories of phaseplane for coupled ocean-atmosphere model ultimately tend tothe stable attractors separately.

关键词： nonlinear perturb ENSO model.

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern institute of physics Chengdu 610041People's Republic of China Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 12. nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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Chinese Science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. XIE Jianzhong1, FENG Songlin3, FAN Dongyu3, ZHANG Ying3, CAI Zhifang3, ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. china 2. Department of physics, {2. Normal University, {2. 100875, china 3. High Energy physics institute, the Chinese Academy of Sciences, beijing 100080, china 4. Archaeology Research institute, Shanxi Province, Xian 710000, china Correspondence should be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of physics Beijing Normal University Beijing 100875 China High Energy physics institute Chinese Academy of Sciences Beijing 100080 China Archaeology Research institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 2. kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (12.1—1368 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—12.9 A.D.) and the Jin Dynasty (1115—12.4 A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析

A new method for multi-exponential inversion of NMR relaxation measurements

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Science china(physics,Mechanics & Astronomy) 2004年第3期47卷 265-276页

作者： WANG Zhongdong1, 2. XIAO Lizhi1 & LIU Tangyan1 1. Petroleum University, beijing 102.49, china 2. Liaohe Petroleum Administration, Panjin 12.011, china Petroleum Universitybeijingchina Liaohe Petroleum AdministrationPanjinchina

A new method for multi-exponential inversion to NMR T1 and T2.relaxation time distributions is suggested and tested. Inversion results are compared with MAP-II which is based on SVD algorithm and widely accepted in the industry. Inversed NMR relaxation spectra that have different pre-assigned relaxation times from echo trains with different SNR confirm that the new method with 16 to 64 equally spaced time constants in logarithm scale will ensure the relaxation distribution. Testing results show that the new inversion algorithm is a valuable tool for rock core NMR experimental analysis and NMR logging data process and interpretation.

关键词： NMR, inversion, relaxation, core analysis, well logging.

Two mode photon bunching effect as witness of quantum criticality in circuit QED

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Science china(physics,Mechanics & Astronomy) 2009年第12期52卷 1898-1905页

作者： AI Qing1,WANG YingDan2.LONG GuiLu1,3 & SUN ChangPu4 1 Department of physics,Tsinghua University,beijing 100084,{2. 2.Department of physics,University of Basel,Klingelbergstrasse 82.4056 Basel,Switzerland 3 Tsinghua National Laboratory for Information Science and Technology,beijing 100084,{2. 4 institute of Theoretical physics,Chinese Academy of Sciences,beijing 100080,{2. Department of physics Tsinghua University Beijing China Department of physics University of Basel Basel Switzerland Tsinghua National Laboratory for Information Science and Technology Beijing China institute of Theoretical physics Chinese Academy of Sciences Beijing China

We suggest a scheme to probe critical phenomena at a quantum phase transition (QPT) using the quantum correlation of two photonic modes simultaneously coupled to a critical system. As an experimentally accessible physical implementation,a circuit QED system is formed by a capacitively coupled Josephson junction qubit array interacting with one superconducting transmission line resonator (TLR). It realizes an Ising chain in the transverse field (ICTF) which interacts with the two magnetic modes propagating in the TLR. We demonstrate that in the vicinity of criticality the originally independent fields tend to display photon bunching effects due to their interaction with the ICTF. Thus,the occurrence of the QPT is reflected by the quantum characteristics of the photonic fields.

关键词： quantum phase transition photon bunching circuit QED