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Synthesis of lateral macrobicyclic cryptand

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Chinese Journal of Chemistry 1983年第1期1卷 67-70页

作者： J.M.LEHN WU Cheng-tai P.PLUMERE Le Bel Institute,Louis Pasteur university,Strasbourg,France Department of Chemistry,wuhan university,wuhan,china. Le Bel Institute Louis Pasteur University Strasbourg France

This paper deals with the synthesis of a new lateral macrobicyclic cryptand ***-tion of 2,6-di（bromomethyl）pyridine with 3.（n-tosylamino）methyl propionate in the presence ofanhydrous KCOat room temperature gave 5 which was hydrolyzed to *** of the latter withexcess sulfonyl chloride afforded 2,6-di（4’-chloroformyl-2’-tosyl-2’-azabutyl）pyridine（7）.Pentaaza-1,5,13.17,28-dithia-20,25-tricyclo[15,5,5,1]-octacosa-7,9,11（28）-triene（10）has been synthesized bythe following sequence of reactions:Condensation of 7 with 1,7-diaza-4,10-dithia-dodecane（3.by highdilution technique in toluene-THF at room femperature afforded 8 which was reduced by diboranein THF solution to give *** of 9 with sodium anthracene in monoglyme produced 10.

关键词： Synthesis of lateral macrobicyclic cryptand

Normal Functions and α-Normal Functions

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Acta Mathematica Sinica,English Series 2000年第3期16卷 399-404页

作者： Yan Xu Department of Mathematics,Nanjing Normal university,Nanjing 210097 P.R.china Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China

This paper has studied two open questions about normal functions due to Lappan,and obtained two corresponding results for α-normal functions.

关键词： Spherical derivative Normal function α-Normal function

A novel extended Kalman filter for a class of nonlinear systems

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Progress in Natural Science:Materials International 2006年第9期16卷 912-918页

作者： DONG Zhe and YOU Zheng (Department of Precision Instrument and Mechanology, Tsinghua university, Beijing 100084, china) [a]Department of Precision Instrument and Mechanology Tsinghua University Beijing China

Estimation of the state variables of nonlinear systems is one of the fundamental and significant problems in control and signal processing. A new extended Kalman filtering approach for a class of nonlinear discrete-time systems in engineering is presented in this paper. In contrast to the celebrated extended Kalman filter (EKF), there is no linearization operation in the design procedure of the filter, and the parameters of the filter are obtained through minimizing a proper upper bound of the mean-square estimation error. Simulation results show that this filter can provide higher estimation precision than that provided by the EKF.

关键词： nonlinear systems state estimation Kalman filtering.

Analytical theory of flexural behavior of concrete beam reinforced with textile-combined steel

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Science china(Technological Sciences) 2010年第6期53卷 1700-1710页

作者： XU ShiLang & YIN ShiPing Department of Civil Engineering,Dalian university of Technology,Dalian 116024,china 1. Department of Civil Engineering Dalian University of Technology Dalian 116024 China

Textile-reinforced concrete (TRC) is a new high performance cementitious composite material,which not only has superior corrosion resistance but also can effectively limit the development of concrete cracks and make the crack width and spacing of concrete become ***,due to the brittle feature of fiber materials,the TRC structural member has no distinct failure symptom when it arrives at its ultimate *** the same time,ordinary reinforced concrete (RC) elements have large dead weight and can not efficiently restrict the expansion of the main crack of structures because of the restriction of their special cover *** order to overcome the disadvantages of both the TRC and the RC,a new architecture reinforced with textile-combined steel is proposed in this study,making full use of the advantages of the above two *** cover concrete at the tension zone of an RC element is partially replaced with TRC and thus the steel reinforcements replaced with textiles are *** with the old one,the new structure has less dead weight and has the merits of service safety and good *** flexural development process of the proper beam with this new structure is investigated in this paper and based on the plane section assumption,analytical equations are derived by using nonlinear analysis theory,including the load-carrying capacity at different stages and moment-curvature relationship and mid-span deflection during the entire loading *** between the calculated and the experimental results reveals satisfactory agreement and thus verifies the feasibility of the equations.

关键词： textile-reinforced concrete limiting the crack beam reinforced with textile-combined steel flexural behavior analytical theory

Regularity of the Attractor for the Dissipative Hamiltonian Amplitude Equation Governing Modulated Wave Instabilities

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Acta Mathematicae Applicatae Sinica 2002年第2期18卷 263-272页

作者： Zheng-de DaiDepartment of Mathematics, Yunnan university, Kunming 650091, china Department of Mathematics Yunnan Normal University Kunming China

In the present paper, the existence of global attractor for dissipative Hamiltonian amplitude equation governing the modulated wave instabilities in E0 is considered. By a decomposition of solution operator, it is sho... 详细信息

关键词： Regularity of Global attractor Hamiltonian amplitude equation

Cracking Behaviour of Al_2O_3.Short Fibre/Al-5.5Zn Composite in TEM

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Journal of Materials Science & Technology 1997年第3期13卷 235-237页

作者： Xiyan ZHANG Tianxin TAN Wenyi PENG and Qing GAO (Southwest Jiaotong university, Chengdu 61003., china) Southwest Jiaotong university Chengdu 610031 China

The micromechanical behaviour of Al2O3.short fibre reinforced Al-5.5Zn matrix composite has been in-situ studied by using TEM. The results show that in the composite the nucleation and propagation of cracks take place mainly in the matrix, as well as in the region near the fibre/matrix interface. It has been also observed that the microcracks can close during *** the fracture property can be characterized by crack open displacement (COD). The cracking characteristic may result from the large strength difference between the matrix and fibre.

关键词： Cracking Behaviour of Al2O3.Short Fibre/Al-5.5Zn Composite in TEM Al Zn

Redistribution of Boron during Ferrite Reaction in Nb-B Microalloyed Steel

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 223-227页

作者： Shanwu Yang Xinlai He(Applied Science School, university of Science and Technology Beijing, Beijing 100083. china) Applied Science School University of Science and Technology Beijing Beijing 100083 China

By contrast of microstructure and boron distribution in the same area of samples, the behavior of boronduring ferrite reaction in Nb-B microalloyed steel was studied. Boron atoms have segregated to original austeniteboundaries betfore ferrite reaction starts during isothermal treatment. The concentration of boron in small Pieces offerrite foming along austenite boundaries may be remarkably higher than that in austenite matrix, but it will reducegradually when the ferrite continuously grows. There is no obvious boron segregation on interface of γ/α and α/α.These facts indicate that ferrite growth is not controlled by diffusion of boron in austenite.

关键词： boron segregation ferrite reaction microalloyed steel

The　Dynamic　Behaviour　Analysis　of　Up－Conversion　Luminescence　in　ErP5O14　Glass

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Chinese Journal of Lasers 1995年第1期B4卷 73-80页

作者： CHEN Jinkai CHEN Xiaobo HUANG Zhiwei YANG Wenqing(Experiment Center,Fujian Normal university, Fuzhou 3.0007,china Physics Department,Nankai university,Tian jing 3.0071,china) Fujian Normal Univ Fuzhou China

ＴｈｅＤｙｎａｍｉｃＢｅｈａｖｉｏｕｒＡｎａｌｙｓｉｓｏｆＵｐ－ＣｏｎｖｅｒｓｉｏｎＬｕｍｉｎｅｓｃｅｎｃｅｉｎＥｒＰ５Ｏ１４ＧｌａｓｓＴｈｅＤｙｎａｍｉｃＢｅｈａｖｉｏｕｒＡｎａｌｙｓｉｓｏｆＵｐ－Ｃｏｎｖｅｒｓｉ... 详细信息

ＴｈｅＤｙｎａｍｉｃＢｅｈａｖｉｏｕｒＡｎａｌｙｓｉｓｏｆＵｐ－ＣｏｎｖｅｒｓｉｏｎＬｕｍｉｎｅｓｃｅｎｃｅｉｎＥｒＰ５Ｏ１４ＧｌａｓｓＴｈｅＤｙｎａｍｉｃＢｅｈａｖｉｏｕｒＡｎａｌｙｓｉｓｏｆＵｐ－ＣｏｎｖｅｒｓｉｏｎＬｕｍｉｎｅｓｃｅｎｃｅ...

关键词： ErP5O(14) glass up-conversion three photon luminescence

NEW APPROACH TO THE LIMITER FUNCTIONS

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Journal of Computational Mathematics 1999年第1期17卷 41-58页

作者： Jin Li Ze-min Chen Zi-qiang Zhu(Beijing university of Aeronautics and Astronautics, Beijing 100083. china) Beijing Univ Aeronaut & Astronaut Beijing 100083 Peoples R China

In this paper we discuss three topics on the designing of the limiter functions. (1) To guarantee the TVD property (2) To maintain enough artificial viscosity. (3. A method to form TVB limiter which can ensure second ... 详细信息

关键词： finite difference methods TVD schemes limiter function