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Chemical Research in Chinese Universities 1992年第2期8卷 164-168页

作者： LU Zhong-e, MA Ying-liang and CHEN Ke-qian (department of Chemistry, Suzhou university, Suzhou, 215006)SUN Zheng-min (laboratory of solid state microstructures, nanjing university, nanjing, 210008)

Introduction Liquid crystals without a double bond bridge between two rings in the linear molecule are more stable chemically and photochemically. Alkyl cyanobiphenyl was synthesized by Richard in 1973. Later, liquid ... 详细信息

关键词： Liquid crystal Mesomorphic state Benzothiazole

Focal plane wave-front sensing algorithm for high-contrast imaging

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Science china(physics,Mechanics & Astronomy) 2009年第8期52卷 1284-1288页

作者： DOU JiangPei1,2,3,REN DeQing1,2,4,ZHU YongTian1,2 & ZHANG Xi1,2,3 1 national Astronomical Observatories/nanjing Institute of Astronomical Optics & Technology,Chinese Academy of Sciences,nanjing 210042,china 2 Key laboratory of Astronomical Optics & Technology,nanjing Institute of Astronomical Optics & Technology,Chinese Academy of Sciences,nanjing 210042,china 3 Graduate university of Chinese Academy of Sciences,Beijing 100049,china 4 physics & Astronomy department,California state university Northridge,18111 Nordhoff Street,Northridge,California 91330-8268,USA national Astronomical Observatories/nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China Key laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China Graduate university of Chinese Academy of Sciences Beijing China physics & Astronomy department California State University Northridge Northridge USA

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star.A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical *** derive an algorithm for the wave-front measurement directly from 3 focal plane *** 3 images are achieved through a deformable mirror to provide specific phases for the optics *** introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front,which is a critical procedure for wave-front *** simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically,which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

关键词： high-contrast imaging multi-image algorithm speckle nulling technique wave-front sensing

铁电体SrBi_2Nb_2O_9电子能带结构的第一性原理研究

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物理学报 2004年第9期53卷 2931-2936页

作者：唐春红蔡孟秋尹真张明生南京大学物理系固体微结构实验室材料分析中心南京工程学院基础部南京210013

采用第一性原理的方法计算了SrBi2 Nb2 O9(SBN)的顺电相、铁电相的电子结构 .顺电相是间接带隙 ,铁电相是直接带隙 ,它们的大小分别为 1 5 7和 2 2 3eV .顺电相和铁电相的价带顶均主要来自于O2p态的贡献 .而顺电相和铁电相的导带底则... 详细信息

采用第一性原理的方法计算了SrBi2 Nb2 O9(SBN)的顺电相、铁电相的电子结构 .顺电相是间接带隙 ,铁电相是直接带隙 ,它们的大小分别为 1 5 7和 2 2 3eV .顺电相和铁电相的价带顶均主要来自于O2p态的贡献 .而顺电相和铁电相的导带底则分别来自Nb 4d态和Bi6p态的贡献 .计算表明SBN铁电相的低的漏电流与Bi6p轨道有关 .由顺电相到铁电相时 ,Nb 4d和O 2p轨道的强的杂化以及部分的Bi O (2 )杂化间接地增强NbO6 八面体的畸变 ,降低了体系的总能量。

关键词：铁电材料顺电相铁电相态密度电子能带结构

Solar release time of solar energetic particles and associated acceleration source in corona

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Chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1,2,3,4, TANG YuHua1 & HAN YanBen4 1 department of Astronomy, nanjing university, nanjing 210093, china 2 Key laboratory of Radiometric Calibration and Validation for Environmental Satellites, china Meteorological Administration, Beijing 100081, china 3 national Center for Space Weather, china Meteorological Administration, Beijing 100081, china 4 national Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, china department of Astronomy Nanjing University Nanjing China Key laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing China national Center for Space Weather China Meteorological Administration Beijing China national Astronomical Observatories Chinese Academy of Sciences Beijing China

Solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1AU. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑

SURFACE AND SIZE EFFECTS OF MAGNETIC PROPERTIES FERROMAGNETIC NANOPARTICLES

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SURFACE AND SIZE EFFECTS OF MAGNETIC PROPERTIES FERROMAGNETI...

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

第8届国际材联电子材料国际研讨会

作者： Huang Zhigao Feng Qian Chen Zhigao Chen Shuiyuan Du Yuowei national laboratory of solid state microstructures nanjing university nanjing 210093 china department of physics Fujian Teachers university Fuzhou 350007 china

＜正＞ Recently, the magnetic properties of magnetic nanoparticles have become a hot topic in magnetic materials. Single magnetic cluster with a few hundred or thousand atoms and the clusters embedded in nonmagnetic matrixes have been studied. The cluster contains both core and surface spins. Surface anisotropy, exchange interaction being different from in the core and incomplete coordination shell give rise to a variety of spin configuration near the surface and complex slain distributions within a particle. Base on Monte Carlo

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Science china Earth Sciences 2004年第3期47卷 265-271页

作者： GE Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, LIU Deliang2 & Chi-yuen Wang3 1. department of Earth Sciences, nanjing university, state Key laboratory of Mineral Deposit, nanjing 210093, china 2. department of Earth and Space Sciences, university of Science and Technology of china, Hefei 230026, china 3. department of Geology and Geophysics, university of California, Berkeley, CA 94720, USA department of Earth Sciences Nanjing University State Key Lab. of Mineral Deposit Nanjing 210093 China Dept. of Earth and Space Sciences Univ. of Science/Technology of China Hefei 230026 China department of Geology and Geophysics University of California Berkeley CA 94720 United States

Based on the observation of the deep bore cores sampled from the state of Cali-fornia, USA, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.

A Feedback-Based Web Search Engine

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Wuhan university Journal of Natural Sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3 , XU Bao-wen 2,3,4 , ZHOU Xiao-yu 2,3,4 1. department of Computer Science and Engineering, nanjing university of Posts and Telecommunications, nanjing 210003, Jiangsu, china 2. department of Computer Science and Engineering, Southeast university, nanjing 210096, Jiangsu, china 3. Jiangsu Institute of Software Quality, nanjing 210096 Jiangsu, china 4. The state Key laboratory of Software Engineering, Wuhan university, Wuhan 430072, Hubei, china department of Computer Science and Engineering Nanjing University of Posts and Telecommunications Nanjing Jiangsu China department of Computer Science and Engineering Southeast University Najing Jiangsu China Jiangsu Institute of Software Quality Nanjing Jiangsu China The state Key laboratory of Software Engineering Wuhan University Wuhan Hubei China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4 Foundation item: Supported by the national Natural Science Fundation of china (60373066). national Grand Fundamental Research 973 Program of china (2002CB31200). Opening Foundation of state Key laboratory of Software Engineering in Wuhan university, Opening Foundation of Jiangsu Key laboratory of Computer Information Processing Technology in Soochow universityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Ab-initio molecular dynamics simulation on nano-system under external pressure

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Science china Mathematics 2004年第Z1期47卷 92-100页

作者： Jl Min, SUN Deyan & GONG XingaoSurface physics laboratory and department of physics, Fudan university, Shanghai 200433, china Institute of solid state physics, Chinese Academy of Sciences, Hefei 230031, china Interdisciplary Center for Theoretical studies, Chinese Academy of Sciences, Beijing 100080, china Surface physics laboratory and department of physics Fudan University Shanghai China Institute of solid state physics Chinese Academy of Sciences Hefei China Interdisciplary Center for Theoretical studies Chinese Academy of Sciences Beijing China

A new constant-pressure molecular dynamics (MD) method is developed to simulate the dynamic behavior and structure transition of finite system under external pressure. In this method, no artificial parameter is introduced and the computation overheads are very small. As an application, a hard-soft transition of single wall carbon nanotube (SWCNT) under external pressure is found, which is in agreement with the experiments.

关键词： phase transition, simulation, nano-particles

Chinese expert consensus on refined diagnosis,treatment,and management of advanced primary liver cancer(2023 edition)

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