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Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3, HUANG Zhenli4. XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong university, Jinan 250100, china 2. School of Information science and engineering, Shandong university, Jinan 250100, china 3. Department of Chemical engineering, Light Industry College of Shandong, Jinan 250100, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of science and technology, Wuhan 4.0074. china 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of Information science and engineering Shandong University 250100 Jinan China 3. Department of Chemical engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4.dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4.dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4.6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064.nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 4..8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 4..2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

SYNTHESIS AND CHARACTERIZATION OF FOUR-ARMED BLOCK POLY(STYRENE-b-p-NITROPHENYL METHACRYLATE)PREPARED BY THE ATRP METHOD

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Chinese Journal of Polymer science 2002年第4期20卷 353-360页

作者： Cai-yuan Pan Lei Tao Ye Liu Department of Polymer science and engineering university of science and {4. of china, Hefei 230026 china Department of Polymer science and engineering University of Science and Technology of China Hefei 230026

A novel tetrafunctional initiator, C [CH_2O (CH_2)_3 OOCCH(Br)CH_3]_4.(1), was synthesized through the reaction oftetraol with α-bromopropionyl chloride, and then was used as initiator of atom transfer radical polymerization (ATRP) in thepreparation of 4.armed polystyrene (PSt) with narrow polydispersity. The structure, molecular weight and molecular weightdistribution (MWD) of each arm were studied by ~1H-NMR and GPC data of hydrolyzed products of the 4.armed PSt. TheATRP of St using 1/CuBr/bpy as initiator system is of 'living' character based on the following evidence: narrow MWD,constant concentration of chain radical during the polymerization, control of molecular weight by the molar ratio of monomerconsumed to 1. The 4.armed poly(St-b-p-nitrophenyl methacrylate) [poly(St-b-NPMA)] was prepared by the ATRP ofNPMA using 4.armed PSt with terminal bromine as the initiator, and characterized by FT-IR, ~1H-NMR spectra and GPCcurves. The micelles with PSt as core, and PNPMA as shell were formed by dropping DMSO into a solution of 4.armedpoly(St-b-NPMA) in DMF, as proved by laser light scatter (LLS) method.

关键词： Tetrafunctional initiator Atom transfer radical polymerization 4.Armed polystyrene 4.Armed poly(styrene-b-pnitrophenyl methacrylate) Unimolecular micelles

ARCHITECTURE OF MANUFACTURING EXECUTION SYSTEM IN THE EXTENDED ENTERPRISE

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Chinese Journal of Mechanical engineering 2002年第1期15卷 90-93页

作者： Song Haisheng College of electronic and Mechanical engineering， Hebei university of science and {4.，Shijiazhuang 050054.china Wang Jiahai Zhang Shu Tongji university College of electronic and Mechanical engineering Hebei University of Science and Technology Shijiazhuang 050054 China

The extended enterprise is formed according to the philosophy of dispersednetworked manufacturing. Manufacturing execution system (MES) can close the information gap whichexists between device control system and production information management system. The functions andthe web-based architecture of the MES in the extended enterprise are introduced. Using thecooperating system models of object-oriented and distributed agents and CORBA, all objects keep touniform interface standards and are easily inserted to object request broker. The utilization ofdistributed MES in extended enterprise can adapt fast change of manufacturing environment andresource. It also can improve the independent management capability of manufacturing cell and theenterprise response capability to global economic competition.

关键词： Extended enterprise Manufacturing execution system Dispersed networkedmanufacturing Agent

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4. LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3, ZHANG Qin4.1. School of Survey and Land Information engineering, Henan Polytechnic university, Jiaozuo 4.4.03, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 4.4.03, china 3. College of Resources and Civil engineering, Northeastern university, Shenyang 110819, china 4. College of Geology engineering and Geomatics, Chang’an university, Xi’an 710054. china [a] School of Survey and Land Information engineering Henan Polytechnic University Jiaozuo 454003 China [b] Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China [c] College of Resources and Civil engineering Northeastern University Shenyang 110819 China [d] College of Geology engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

Sidelobe reduction based on spectrum reshaping in microwave imaging

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science china(Information sciences) 2011年第1期54卷 204-212页

作者： WANG HuaiJun,SU Yi,XU HongBo & ZHU YuTao School of electronic science and engineering,National university of Defense {4., Changsha 4.0073,china 1. School of electronic science and engineering National University of Defense Technology Changsha 410073 China

Sidelobe artifacts are a common problem in image reconstruction from finite-extent Fourier data obtained by microwave imaging *** order to enhance the image quality,sidelobe reduction must be *** the sidelobe reduction in microwave imaging as the research subject,this paper presents Fourier imaging technique *** the point spread function is obtained through Fourier inversion of rectangular spectral support data and the changing effect of sidelobe direction due to reshaping spectral support is *** reshaping makes that the sidelobes of two Fourier images do not *** on the idea of separating sidelobes from mainlobe,a nolve method that reduces sidelobe levels while maintaining the imaging resolution is *** performance of this method is ***,the simulated and measured data of typical microwave imaging systems such as synthetic aperture radar(SAR),inverse synthetic aperture radar(ISAR)and real aperture radar are used to demonstrate the validity of the proposed method.

关键词： microwave imaging Fourier imaging sidelobe reduction spatial spectrum point spread function

Dynamics of the generalized 3x + 1 function determined by its fractal images

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Progress in Natural science:Materials International 2008年第2期18卷 217-223页

作者： Xingyuan Wang ,Xuejing Yu School of electronic & Information engineering,Dalian university of technology,Dalian 116024.{4. School of electronic & Information engineering Dalian University of Technology Dalian 116024 China

Two different complex maps were obtained by generalizing 3x + 1 function to the complex plane,and fractal images for these two complex maps were constructed by using escape time,stopping time and total stopping time arithmetic. The dynamics of the generalized 3x + 1 function based on the structural characteristics of the fractal images was studied. We found that: (1) the size and structure of the stable regions,stopping regions,total stopping regions,and divergent regions for the three types of fractal images depend on convergence rate of the map on the x and y axes. (2) The black stable regions constructed,respectively,by escape time and total stopping time are almost overlapped,demonstrating that 3x + 1 function converged steadily. (3) All of the three fractal images are symmetric to the real axis. The structures on the neighborhood of positive integer number are symmetric to a perpendicular line,which is corresponding to the point or its nearby points on the x axis. And the structures have complicated fractal structure characteristics. These findings indicate that the generalized 3x + 1 function on integer number and its neighborhood contains plentiful information in the complex plane.

关键词： Generalized 3x + 1 function Fractal images Dynamics

Stability analysis of cellular neural networks with time-varying delay

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Journal of Systems engineering and electronics 2009年第2期20卷 266-273页

作者： Wang Xingang1,4. Zhang Dongmei2 & Liu Jun3 1. Coll. of Information engineering, Zhejiang Univ. of technology, Hangzhou 310032, P. R. china 2. Coll. of science, Zhejiang Univ. of technology, Hangzhou 310032, P. R. china 3. Coll. of science, Beihua Univ., Jilin 132000, P. R. china 4. School of Computer engineering and science, Shanghai Univ., Shanghai 200072, P. R. china Coll. of Information engineering Zhejiang Univ. of Technology Hangzhou 310032 P. R. China School of Computer engineering and science Shanghai Univ. Shanghai 200072 P. R. China Coll. of science Zhejiang Univ. of Technology Hangzhou 310032 P. R. China Coll. of science Beihua Univ. Jilin 132000 P. R. China

The global asymptotic stability of cellular neural networks with delays is investigated. Three kinds of time delays have been considered. New delay-dependent stability criteria are proposed and are formulated as the feasibility of some linear matrix inequalities, which can be checked easily by resorting to the recently developed interior-point algorithms. Based on the Finsler Lemma, it is theoretically proved that the proposed stability criteria are less conservative than some existing results.

关键词： cellular neural networks time-varying delay integral inequality

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3, FENG ChengMing1 1 Mechanical and electronic engineering College, Shandong Agricultural university, Tai’an 271018, china 2 College of Materials {4. and engineering, university of {4. and technology, Beijing 100083, china 3 College of Material {4. and engineering, Beijing university of Chemical technology, Beijing 100029, china Mechanical electronic engineering College Shandong Agricultural University Tai’an 271018 China College of Materials science engineering University of Science technology Beijing 100083 China College of Material science engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

Three-Dimensional and Cross-sectional Characteristics of Normal Grain Growth Based on Monte Carlo Simulation

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 129-133,139页

作者： Xiaoyan Song Guoquan Liu(Material science and engineering School, university of science and {4. Beijing, Beijing 100083, china)(Department of Materials science and engineering, Hebei university of {4., Tianjin 300130, china) Material science and engineering School University of Science and Technology Beijing Beijing 100083 China Departments of Materials science and engineering Hebei University of Technology Tianjin 300130 China

An appropriate Monte Carlo method was developed to simulate the three-dimensional normal grain growth more completely. Comparative investigation on the three-dimensional and the cross-sectional characteristics of normal grain growth was done. It was found that the time exponent of grain growth determined from cross-section exhibits the same rule of increasing slowly with time and approaching the theoretical value n = 0.5 of steadygrain growth as the three-dimensional (3-D) system. From change of the number of grains per unit area with timemeasured in cross-section, the state of 3-D normal grain growth may be predicted. The gtain size distribution incross-section is different from that in 3-D system and can not express the evolution characteristic of the 3-D distribution. Furthermore, there exists statistical connection between the topological parameters in cross-section and thosein three-dimensions.

关键词： Monte Carlo simulation normal grain growth three-dimension cross-section characteristics