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Frontal genesis of moisture atmosphere during the early 2008 persistent freezing-rain event in southern china

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Science china Earth Sciences 2010年第3期53卷 454-464页

作者： QIAN WeiHong1 & FU JiaoLan1,2 1 department of Atmospheric Sciences, School of physics, Peking university, Beijing 100871, china 2 National Meteorological Center of CMA, Beijing, 100081, china 1. department of Atmospheric Sciences School of Physics Peking University Beijing 100871 China2. National Meteorological Center of CMA Beijing 100081 China

From January 10 to February 2, 2008, a severe and persistent freezing-rain event occurred in southern and southwestern china. Here we use an observational analysis to compare the persistent freezing-rain event in the early 2008 with the winter precipita- tion in the late 2007 over south of the Yangtze River (Jiangnan). The persistent freezing-rain event was directly linked to the activity of quasi-stationary front. The gradient of equivalent temperature (ET) can well indicate the frontal genesis of moist atmosphere (moisture front) and its activity as well as its relationship with precipitation belt. The precipitation types (snow and freezing rains) are related to the vertical structure of moisture front. The inversion profile of ET vertical distribution is a typical synoptic condition that caused the freezing-rain event. The horizontal gradient of ET with a criterion of 10℃ / 100 km, which reflects the accumulation and release of atmospheric energy, can be applied to predict the precipitation 5-10 days in advance.

关键词： freezing-rain event frontal genesis extended-range weather forecast winter Jiangnan

Organic Light Emitting Diodes with p-Si Anodes and Semitransparent Ce/Au Cathodes

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Journal of Wuhan university of Technology(Materials Science) 2011年第2期26卷 208-211页

作者：孙志国姜广智 department of Medical Technology Henan Medical College for Staff and Workers department of physics Zhengzhou Normal University

The Ce （x nm）/Au （15 nm） stacked layers were used as semitransparent cathodes in the top-emission organic light emitting devices （TOLEDs） fabricated on a p-type silicon anodes and substrate,where x varies from 4 to *** consequence of the Ce layer thickness on transmittance and the device performance were studied when the organic layers NPB （60 nm）/ALQ （60 nm） were kept unchanged,where NPB was N,N＇-bis-（1-naphthl）-diphenyl-1,1＇-biphenyl-4,4＇-diamine,and AlQ is tris-（8-hydroxyquinoline） *** cathode of Ce （11 nm）/Au （15 nm） has a transparency of 46%,and the TOLED with it achieves the highest luminescence efficiencies：a current efficiency of 0.91 cd/A at 13.7 V and a peak power efficiency of 0.28 lm/W at 9 *** turn-on voltage is 3.0 *** Ce/Au cathode is both chemically and electrically stable.

关键词： organic light emitting device transparent cathode Ce

Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2,3 1 Key Laboratory of Particle Astrophysics,Institute of High Energy physics,Chinese Academy of Sciences,Beijing 100049,china 2.department of physics & Center for Astrophysics,Tsinghua university,Beijing 100084,china 3 department of Engineering physics & Center for Astrophysics,Tsinghua university,Beijing 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 remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong physics department, College of Information Science and Engineering, Ocean university of china, Qingdao 266100, Shandong, china [a] physics department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5 meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3P, TIP4P, MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4P, and TIP3P potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

Light tunneling in a pair structure consisting of epsilon-negative and mu-negative media

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Light tunneling in a pair structure consisting of epsilon-ne...

Diffuse interstellar absorption bands

2007亚洲光电子会议量子光学在计算与通信中的应用分会场

作者： Tuanhui Feng, Yunhui Li*, and Hong Chen Pohl Institute of Solid State physics, Tongji university Shanghai 200092, china Yunlong Shi Institute of Solid State physics, shanxi datong university, datong 037009, china

In this paper, the tunneling phenomenon occurring in a pair structure consisting of epsilon-negative (ENG) and mu-negative (MNG) metamaterials is investigated. First, the ENG and MNG metamaterials are fabricated using coplanar waveguide loading with lumped-element series capacitors and shunt inductors. Then, the tunneling phenomenon occurring in the ENG-MNG pair is experimentally demonstrated. Finally, the properties of the tunneling mode are studied and the results show that the tunneling frequency is independent of the pair length and the electric field of the tunneling mode is highly localized at the interface of the ENG-MNG pair.

关键词： metamaterials, epsilon-negative, mu-negative, ENG-MNG pair, tunneling.

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Science china(physics,Mechanics & Astronomy) 2009年第4期52卷 489-501页

作者： XIANG FuYuan1,2,LIANG ShunLin2 & LI AiGen2,3 1 Faculty of Materials,Photoelectronics and physics,Xiangtan university,Xiangtan 411105,china 2.department of physics and Astronomy,university of Missouri,Columbia,MO 65211,USA 3 Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210008,china 1. Faculty of Materials Photoelectronics and Physics Xiangtan University Xiangtan 411105 China 2. department of physics and Astronomy University of Missouri Columbia MO 65211 USA 3. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

关键词： astrophysics interstellar matter interstellar extinction diffuse interstellar band circumstellar environment

A new approximating method for Holstein model

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Science china(physics,Mechanics & Astronomy) 2010年第1期53卷 44-48页

作者： REN XueZao 1 , LIAO Xu 1 , LI Lei 1 & WANG KeLin 2 1 School of Science, Southwest university of Science and Technology, Mian Yang 621010, china 2.department of Modern physics, university of Science and Technology of china, Hefei 230026, china 1. School of Science Southwest University of Science and Technology Mian Yang 621010 China2. Department of Modern Physics University of Science and Technology of China Hefei 230026 China

A new approach-the method of coherent state orthogonal expansion is developed for one-dimensional Holstein model. In zeroth order approximation, the formula of ground state energy is deduced analytically and the solutions in strong- and weak-coupling limits are obtained correctly. When the trial wave-function of ground state is expanded to the second order, the obtained ground state energy agrees quite well with that calculated by numerical method in all coupling regimes. The present approach can be easily generalized to the situations of higher dimensions and more electrons.

关键词： coherent-state orthogonal expansion polaron simulated annealing method

The Ground and Excitation Levels of the Trimer

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Wuhan university Journal of Natural Sciences 1998年第2期3卷 163-164页

作者： You Pu(department of physics, Wuhan university, Wuhan 430072,china) Wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The ground and excited levels of the trimer (4He)3 are obtained theoretically by solving the 2-D Faddeev integral equation in the momentum space. In solving the equation, the direct matrix inversion method (I. M.) is used instead of the iteration and Pade approximate method. The new HFD-B Aziz potential ν is used in the calculation.

关键词： Trimer Faddeev equation matrix inversion method

Enhancement of magnetism of Zn0.95Co0.05O films by p-type Cu+ doping

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Progress in Natural Science:Materials International 2011年第1期21卷 31-35页

作者： Wei-chang HAO~(1,5),Jian-jun LI~2,Huai-zhe XU~3,Jia-ou WANG~4,Tian-min WANG~1 1.Center of Materials physics and Chemistry,Beihang university,Beijing 100083,china 2.department of Materials Science and Engineering, Anhui university of Science and Technology,Huainan 232001,china 3.department of physics,Beihang university,Beijing 100083,china 4.Beijing Synchrotron Radiation Facility,Institute of High Energy physics, Chinese Academy of Sciences,100049,china 5.Key Laboratory of Micro-nano Measurement,Manipulation and physics, Ministry of Education,Beihang university,Beijing 100191,china [a] Center of Materials physics and Chemistry Beihang University Beijing 100083 China [b] department of Materials Science and Engineering Anhui University of Science and Technology Huainan 232001 China [c] department of physics Beihang University Beijing 100083 China [d] Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences 100049 China [e] Key Laboratory of Micro-nano Measurement Manipulation and Physics Ministry of Education Beihang University Beijing 100191 China

Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04O thin films were fabricated on Si（111） substrate by the reactive magnetron sputtering method at different O-Ar *** characterizations by X-ray diffractometry（XRD）,X-ray photo-electronic spectrum（XPS）, and electron paramagnetic resonance（EPR） indicate that the doped Cu ions substitute the Zn2+ions in the ZnO *** doped Cu ions are in Cu+and Cu2+mixture valence *** ferromagnetism of the Zn0.91Co0.05Cu0.04O film increases gradually the increasing Cu+ions *** results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ions themselves,but owing to the enhancement of magnetic interaction between Co ions,which suggests that p-type doping of Cu+ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词： Zn0.95Co0.05O films Zn0.91Co0.05Cu0.04O films magnetic semiconductors magnetic coupling co-doping