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Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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science {1. Chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1.2.& HU Weixiao1.1. Department of Pharmaceutical {1., Zhejiang University of Technology, hangzhou 31.032. {2. 2. Department of Applied Chemistry, Zhejiang Institute of {1. and Technology, hangzhou 31.033, {2. 1. Department of Pharmaceutical science Zhejiang University of Technology 310032 Hangzhou China 2. Department of Applied Chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1. with a = 0.71.3(4) nm, b = 1.1.39(2. nm, c = 1.4572.3) nm, α= 1.2.1.(2.°, β= 99.81.3)°, γ= 91.1.(3)°, Z = 2. V = 1.1..6(7) nm3, μ = 2.1.0} mm?1.and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 1. coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

Lipschitz continuity of best approximations and Chebyshev centers

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Chinese science Bulletin 1998年第3期43卷 185-188页

作者： LI Chong 1.and WANG Xinghua 2.1. Center for Mathematical {1.s, Zhejiang University, hangzhou 31.02., {2. 2. Department of Mathematics, hangzhou University, hangzhou 31.02., {2. Center for Mathematical sciences Zhejiang University Hangzhou China Department of Mathematics Hangzhou University Hangzhou China

The Lipschitz continuity results are given for best approximations and Chebyshev centers. Consequently, the open problem presented by Septycki and Vleck is solved completely.

关键词： best approximation Chebyshev center uniform convexity.

Constrained Bézier curves' best multi-degree reduction in the L2.norm

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Progress in Natural science:Materials International 2005年第9期15卷 843-850页

作者： ZHANG Renjiang 1.2.** and WANG Guojin1.1. Institute of Computer Images and Graphics, Zhejiang University, {1. 31.02., china 2. china Institute of Metrology, Zhejiang, {1. 31.034, china) Institute of Computer Images and Graphics Zhejiang University Hangzhou 310027 China. State Key Laboratory of CAD&CG Zhejiang University Hangzhou 310027 China. china Institute of Metrology Zhejiang Hangzhou 310034 China

In computer aided geometric design, the degree reduction of the parameter curve is a key technique in data exchange and data compression. The various existing methods of degree reduction cannot decide whether the degree reduction curve satisfying the given tolerance exists beforehand, cannot give approximation of the best multi-degree reduction, or cannot provide explicit expression and error formula of the degree reduction curve. In this paper, we propose an entirely new method, which can hurdle the above flaws completely. For a given Bézier curve of degree n, we can easily decide whether a Bézier reduction curve of degree m exists, which has equal derivatives with the given curve up to （r-1.-th and （s-1.-th orders （r,s≤m） respectively at the endpoints, so the approximating error is less than the given tolerance ε in the L2.norm. If the curve exists, the explicit expression can be given.

关键词： computer aided design Bézier curve degree reduction L2.norm tolerance.

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1.and Liu Shenquan2.1. Department of Mathematics, {1. Normal University, {1. 31.036, {2. 2. Department of Applied Mathematics, school of Mathematical sciences, South {2. University of Technology, Guangzhou 51.640, {2.) Department of Mathematics Hangzhou Normal University Hangzhou 310036 China Department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

Shape blending of artistic brushstroke represented by disk B-spline curves

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Progress in Natural science:Materials International 2007年第12期17卷 1501-1507页

作者： Cheng Min1.2.and Wang Guojin1.1. Department of Mathematics, Zhejiang University, {1. 31.02., china 2. Department of Mathematics, Zhejiang University of Technology, {1. 31.032. china) Department of Mathematics Zhejiang University Hangzhou 310027 China 2. Department of Mathematics Zhejiang University of Technology Hangzhou 310032 China

This paper presents an algorithm for automatically generating in-between frames of two artistic brushstrokes. The basic idea of the algorithm is to represent the two key frames of artistic brushstrokes in disk B-spline curves, and then make blending of their geometric intrinsic variables. Given two key frames of artistic brushstrokes, the skeleton curves can be obtained by certain skeleton-based techniques. After disk B-spline representation of the key frames is generated, interpolation of the intrinsic variables of the initial and the target disk B-spline curves is carried out. Examples show that this method can efficiently create in-between frames of artistic brushstrokes.

关键词： computer aided calligraphy shape blending brushstroke disk B-spline curve skeleton.

Networked Kalman filtering with combined constraints of bandwidth and random delay

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science {1.(Information sciences) 2012年第10期55卷 2343-2357页

作者： GE QuanBo 1.2.WEN ChengLin 1.& XU TingLiang 1.1.{1. of Automation,hangzhou {2. University,hangzhou 31.01.,china 2.State Key Laboratory of Industrial Control Technology,Zhejiang University,hangzhou 31.02.,china 1. school of Automation Hangzhou Dianzi University Hangzhou 310018 China2. State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

Kalman filter is a powerful tool in target tracking and self-localization across wireless sensor networks with many *** paper considers the filters design for networked systems with combined constraints of bandwidth and random delay,and proposes a kind of universal networked Kalman estimator for given linear time invariant(LTI) or determinate parameters(DP) systems,which are also called linear and determinate parameters(LDP) systems ***,two modeling ways to treat bit quantization error vector are given and the corresponding LDP systems taken after bit quantization are ***,we introduce an equivalent weighted summation form of the conventional linear Kalman filter,which fully uses two essential characteristics,namely offline computation property from the LDP systems and linear weighted summation property from the linear minimum mean square error ***,by adopting the replacement and innovation compensation operations,a kind of integrated networked estimator,involving two estimation algorithms with different modeling ways to bit quantization error actually,is presented based on the weighted summation filter for random delay *** proposed universal networked estimation algorithms have some outstanding advantages such as extensive application,concise algorithm structure,high estimate accuracy,and good running *** examples are demonstrated to validate the proposed networked estimation algorithms.

关键词： Kalman filter LDP systems LMMSE limited bandwidth random delay

Numerical research on the 3D fiber orientation distribution in arbitrary planar flows

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Progress in Natural science:Materials International 2007年第11期17卷 1357-1362页

作者： Zhou Kun1.and Lin Jianzhong1.2.1. State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, {1. 31.02., china 2. china Jiliang University, {1. 31.01., china) State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China china Jiliang University Hangzhou 310018 China

The fiber orientation distribution in a fiber suspension flow was investigated by a finite difference scheme in spherical coordinates. The diffusivity was transformed between Cartesian and spherical coordinates through tensor analysis to obtain efficiency. It is found that under simple shear flow condition the diffusivity in the azimuthal direction, Dr, has greater effect on the orientation distribution than that in the colatitude direction, Drθθ.

关键词： fiber suspension flow orientation distribution diffusivity

Numerical simulation of the efficiency of mixing in heterogeneous microchannels with patterned surface potentials

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Progress in Natural science:Materials International 2006年第12期16卷 1322-1328页

作者： ZHANG Kai~1. LIN Jianzhong~ 1.2.** and LI Huijun~1.1. State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, {1. 31.02., china 2. china Jiliang University, {1. 31.01., china) [a]State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hanghou China [b]china Jiliang University Hangzhou China

The mixing of samples in heterogeneous microchannels with a periodically stepwise surface potential was analyzed numerically using the control volume method. The equations describing the wall potential and external potential were solved first to get the distribution of wall potential and external potential, respectively, then the momentum equation was solved to get the developed flow field. Finally, the mass transport equation was solved to get the concentration field. The simulation results show that the distribution of samples at the inlet of the microchannel determines its theoretical value of concentration, therefore, the pattern of the distribution of samples at the inlet and its corresponding velocity can be changed to get the desirable concentration of solute. The heterogeneous wall potential almost has no effect on the mixing of samples in two-inlet microfluidic devices. For three-inlet microfluidic devices, the comprehensive ability of transportation and mixing has an optimization when the ratio of periodic length of wall potential to the height of the microchannel is about 4.88. The above conclusions are helpful to the optimization of the design of microfluidic devices.

关键词： microchannel mixing efficiency electroosmosis numerical simulation.

Generative computer simulation for parallel layout of multi-story row house cluster

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science {1.(Technological sciences) 2010年第7期53卷 1785-1791页

作者： DING XiYing1.2.1.ZhenjiangUniversity, {1. 31.058, china 2.Zhejiang University of {2. & Technology, {1. 31.058, china 1. Zhenjiang University Hangzhou 310058 China2. Zhejiang University of Science & Technology Hangzhou 310058 China

This study has established the functions between the environmental conditions and the inhabitants’ preferences for multi-story row house cluster with parallel layout, based on the data from the questionnaires’ in Beijing. A program has been written with multi-agent system and generative computer simulation approaches. The emergence candidate layout plans can be referenced and chosen by architects.

关键词： multi-agent system bottom up generative computer simulation multistory row house cluster parallel layout