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Boundary Exact Controllability for Naghdi’s Models

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Boundary Exact Controllability for Naghdi’s Models

第十九届中国控制会议

作者： Peng-Fei Yao institute of Systems Science, academy of Mathematics and Systems Science, the chinese academy of sciences, beijing 100080, china.

＜正＞We consider some observability inequalities for the Naghdi shell from boundary. An estimate is established by the geometric multiplier method in the case that no boundary conditions are imposed. Then the estimate yields continuously observability inequalities for two kinds of boundary conditions which have a physical meaning with an explicit observability time;hence, by duality, exact controllability results. All the observability inequalities are subject to curvature conditions of the middle surface of the shell which are easy to check.

关键词： the Naghdi model the Bochner technique observability inequality

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异同判断加工中整体和局部特征的作用

心理学报 2004年第6期36卷 681-689页

作者：周国梅傅小兰中国科学院心理研究所北京100101

采用三种整体局部特征(关系-属性,全局-局部,抽象-具体)图形,要求3组大学生被试完成异同判断任务,以考察异同判断加工中整体和局部特征的作用,探讨异同比较的加工机制。三个实验的结果表明:(1)三种整体特征均可加速同反应,因而不支持同... 详细信息

采用三种整体局部特征(关系-属性,全局-局部,抽象-具体)图形,要求3组大学生被试完成异同判断任务,以考察异同判断加工中整体和局部特征的作用,探讨异同比较的加工机制。三个实验的结果表明:(1)三种整体特征均可加速同反应,因而不支持同判断加工是整体匹配的观点;(2)存在快同效应,但并不支持同判断的快速加工器对整个刺激加工完成后慢速比较器才开始工作的观点;(3)异反应时随差异特征的增多而减小,从而进一步支持异判断是分析加工、自终止的观点;(4)异反应时随差异特征从上至下、从整体到局部而增加,意味着异判断加工的顺序可能是自上而下、从整体到局部。上述结果支持研究假设:同判断的快速加工器先加工整体特征,然后再和异判断的慢速比较器一起开始加工局部特征。

关键词：异同比较,双过程模型,整体加工,快同效应

维普期刊数据库

A study on synthesis and oxidation mechanism of mono-alkyl phosphate

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Journal of Pharmaceutical Analysis 2009年第3期21卷 172-175,188页

作者： Sheng Wang1,Shu-yun Yan2,Qing-guo Ye21. chinese Research academy of Environmental Science,beijing 100012 2.Qingdao University of Science and Technology,Qingdao 266042,china. chinese Research academy of Environmental Science Beijing 100012 China Qingdao University of Science and Technology Qingdao 266042 China

Oxidation of white phosphorus by peroxides to produce mono-alkyl phosphate in the alcoholic solution has been studied under non-and catalytic conditions. In this paper,the mechanism of the oxidation process was analyzed. The content of mono-alkyl phosphate in the product is affected by different types of alcoholic solution and peroxide solvent. The result shows the availability of the following order for the activity of the peroxide solvent and alcoholic solutions-tert-butyl hydroperoxide>(di) benzoyl peroxide>hydroperoxide; methanol>n-butyl alcohol>phenol. Under optimized reaction conditions:n(white phosphorus)︰n(tert-butyl hydroperoxide)︰n(methanol)=1︰10︰12,reaction temperature 80 ℃,reaction time 2.5 h,products of 80.0% mono-alkyl phosphonates can be provided when white phosphorus undergoes oxidation by tert-butyl hydroperoxide in the methanol solutions. When Cu(Ⅰ),and Cu(Ⅱ) complexes are used as catalysts,it is possible to significantly enhance the oxidation of white phosphorus with the increase in the reaction rate. The order for activity of catalysts is Cu(acac)2>Cu (CH3COO)2>Cu (C3H7COO)2>CuI>CuCl2. Noticeably,with Cu(acac)2 as catalyst,the selectivity for mono-alkyl phosphonates can reach 95% under adequate reaction conditions.

关键词： white phosphorus pentoxide mono-alkyl phosphate copper

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Lignin biosynthesis and its molecular regulation

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Progress in Natural Science:Materials International 2003年第5期 3-10页

作者： LIN Zhanbing, MA Qinghu and XU Yang(Key Laboratory of Photosynthesis and Environmental Molecular Physiology, institute of Botany, chinese academy of sciences, beijing 100093, china) Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Lignin biosynthesis has become increasingly highlighted because it plays an important role in the growth and development of plant, in the systematic evolution of plant and in the human life. Due to the progress in the field of lignin studies in recent years, the lignin biosynthesis pathway has been revised. Here we discuss some genetic engineering approaches on lignin biosynthesis, and conceive strategy to regulate lignin biosynthesis in order to use lignin resource more efficiently in agricultural and industrial productions.

关键词： lignin biosynthesis molecular regulation genetic manipulation.

Dielectronic Recombination Rate Coefficients for Nickel-like Ytterbium

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chinese Journal of Lasers 1996年第3期B5卷 242-247页

作者： ZHAO Libol LI Shichang(institute of Physics, Academic Sinica, P. O. Box 603, beijing 100080,institute of Applied Physics and Computational Mathematics, P. O. Box 8009, beijing, china) Inst of Physics Academia Sinica Beijing China

Ｄｉｅｌｅｃｔｒｏｎｉｃ　Ｒｅｃｏｍｂｉｎａｔｉｏｎ　Ｒａｔｅ　Ｃｏｅｆｆｉｃｉｅｎｔｓ　ｆｏｒ　Ｎｉｃｋｅｌ－ｌｉｋｅ　ＹｔｔｅｒｂｉｕｍＤｉｅｌｅｃｔｒｏｎｉｃＲｅｃｏｍｂｉｎａｔｉｏｎＲａｔｅＣｏｅｆｆｉｃｉｅ... 详细信息

Ｄｉｅｌｅｃｔｒｏｎｉｃ　Ｒｅｃｏｍｂｉｎａｔｉｏｎ　Ｒａｔｅ　Ｃｏｅｆｆｉｃｉｅｎｔｓ　ｆｏｒ　Ｎｉｃｋｅｌ－ｌｉｋｅ　ＹｔｔｅｒｂｉｕｍＤｉｅｌｅｃｔｒｏｎｉｃＲｅｃｏｍｂｉｎａｔｉｏｎＲａｔｅＣｏｅｆｆｉｃｉｅｎｔｓｆｏｒＮｉｃｋｅｌ－ｌｉｋｅ...

关键词： dielectronic recombination autoionizing state Auger rate

Heat Sensitivel is essential for protecting editing of accD chloroplast transcripts and chloroplast biogenesis in Arabidopsis under heat stress

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Heat Sensitivel is essential for protecting editing of accD ...

2011全国植物生物学研讨会

作者： Linlin Zhong,Congming Lu~* Key Laboratory of Photobiology,institute of Botany,chinese academy of sciences,beijing 100093, china

High temperature is one of the major environmental stresses that greatly depress the growth of *** plants have evolved multiple mechanisms to adapt to heat stress,the detailed molecular mechanisms remain be *** this study,we characterized the heat sensitive1(hs1) mutant of Arabidopsis thaliana,which showed albino phenotype under heat stress(30℃) but had no significant difference with wild type under normal growth temperature(22℃).Under heat stress condition,hs1 had lower photosystemⅠandⅡactivity,and chloroplast development was arrested. Immunoblot analyses showed that the levels of plastid-encoded proteins were reduced

关键词： Chloroplast biogenesis Heat Sensitive1 heat stress RNA editing accD Arabidopsis

Planetary wave oscillations in sporadic E layer occurrence at Wuhan

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Planetary wave oscillations in sporadic E layer occurrence a...

中国科学院地质与地球物理研究所2008学术年会

作者： Xiaomin Zuo~(1,2,3,4) and Weixing Wan~1 1 institute of Geology and Geophysics,chinese academy of sciences,beijing,100029,china 2 Mathematics and Physics Department,china University of Geosciences,430074,china 3 Wuhan institute of Physics and Mathematics,chinese academy of sciences,china 4 Graduate School,chinese academy of sciences,china

Quasi 6-day oscillations in E occurrence were observed to occur in relation with planetary wave activity at Wuhan,china(30.6°N,114.5°E).Wavelet analysis of E occurrence time series revealed that a strong 5- to 7-day oscillation was present during the period from about day 120 to 137 of *** same quasi 6-day planetary wave oscillation was also found to dominate the spectrum of concurrent wind data measured in the 80- to 100-km region by a meteor radar,in agreement with the E *** is also a great deal of similarity between the 5- to 7-day band-pass filtered waveforms of E occurrence and the wind *** estimating the wave phase changes with altitude,the quasi 6-day PW in the zonal wind was found to be in phase with the sporadic E layer critical frequency,fE,at about 115 km,close to the observed E *** quasi 6-day PW modulation was also present in the amplitude of the 12-h and 24-h periodicities which existed in the fE time *** present results provide new evidence in favor of a planetary wave indirect role on E formation through the modulation of tides,which in line with previous studies by Haldoupis and Pancheva(2002),and Pancheva et al.(2003).

关键词： Sporadic E layers planetary waves atmospheric tides PW modulation of tides

Explicit analytical solutions of axisymmetric laminar natural convection along vertical tubes

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Progress in Natural Science:Materials International 2005年第3期 66-69页

作者： CAI Ruixian ˇˇ ,ZHANG Na and GOU Chenhua (institute of Engineering Thermophysics,chinese academy of sciences,beijing100080,china) institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China

There are many natural convection processes in various fields,and it is still valuable to investigate the fluid dynamics and heat transfer of natural *** analytical solutions are meaningful in both theoretical investigation and practical ***-cially,they can be used as the benchmark solutions to check the numerical solutions and to develop numerical differencing schemes,grid generation methods and so *** explicit analytical solutions of axisymmetric steady laminar natural convection along a vertical tube with porous wall and between two vertical concentric tubes are derived for better understanding of the flow and heat transfer as well as promot-ing the computational fluid dynamics and computational heat transfer.

关键词： analytical solution natural convection laminar flow boundary layer vertical cylindrical tube.

Research on Range-gated Laser Active Illuminating Technology

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微计算机信息 2006年第19期 51-53页

作者： (Electric and electronic Engineering College,Changchun University of Technology,Changchun130012,china)Wang,Dongmei (Changchun institute of Optics, Fine Mechanics and Physics, chinese academy of sciences, Changchun 130031,china) Wang,Dongmei Zhang,Tao Yan,Feng (Graduate School of sciences academy of china,, beijing 100039) Wang,Dongmei Zhang,Tao Yan,Feng

The laser active illuminated imaging technology utilizes near - infrared laser as illuminated source, the objects are detected and imaging in weak brightness and long range. Synchronism control technology is the crucial technology in range- gated laser active imaging system. In this paper detailed expound on the principle of laser active imaging、laser emission system and receiver technology , at one time expound detailed on range- gated technology , finally analyzed developmental status and foreground in homeland and o- versea about laser active imaging.

关键词： Laser active imaging Range gate CCD camera