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Fluorescence Enhancing Effect of OP on Ga(Ⅲ)-ECBBR system and its Analytical Application

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Rare Metals 2001年第2期20卷 130-132页

作者： Jinzhang Gao, Jianniao Tian, Yanchun Zhao, the Yang, Jingguo Hou, Jingwan Kang (chemistry and Chemical Engineering college, Northwest normal university, Lanzhou 730070, china) 西北师范大学甘肃兰州 730070

The fluorophotometric determination of gallium(Ⅲ) With eriochrome blue black R (ECBBR) was investigated in the presence of OP at pH 2.0n.5. The calibration graph has a good linear relationship in the rabid of 1.6×10-7-1.2× 10-5 mol/L Ga(Ⅲ). The effect of foreign ions was studied and the proposed method was applied to the determination of gallium in aluminum alloy.

关键词： gallium, eriochrome blue black R OP aluminum alloy

ON THE GENERALIZED INVERSE NEVILLE-TYPE MATRIX-VALUED RATIONAL INTERPOLANTS

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Journal of Computational Mathematics 2003年第2期21卷 157-166页

作者： Zhibing Chen9+(Department of Mathematics, normal college, Shenzhen university, Shenzhen 518060, china) Department of Mathematics Normal College Shenzhen University Shenzhen 518060

A new kind of matrix-valued rational interpolants is recursively established by means of generalized Samelson inverse for matrices, with scalar numerator and matrix-valued denominator. In this respect, it is essentially different from that of the previous works [7, 9], where the matrix-valued rational interpolants is in Thiele-type continued fraction form with matrix-valued numerator and scalar denominator. For both univariate and bivariate cases, sufficient conditions for existence, characterisation and uniqueness in some sense are proved respectively, and an error formula for the univariate interpolating function is also given. The results obtained in this paper are illustrated with some numerical examples.

关键词： Generalized inverse for matrices Neville-type Rational interpolants.

Identification of Semen Celosiae and Cockscomb Flower Using Continuous Wavelet Transform with FTIR

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稀有金属材料与工程 2006年第S3期 614-616页

作者： Changjiang Zhang~1 Cungui Cheng~2 (1.college of Mathematics,Physics and Information Engineering,Zhejiang normal university,Jinhua 321004,china) (2.college of chemistry and Life Science,Zhejiang normal university,Jinhua 321004,china)

Infrared spectra of semen celosiae and cockscomb flower can be obtained directly,quickly and accurately employing Fourier transform infrared spectroscopy (FTIR) with OMN1 *** wavelet transform (CWT) is employed to zoom in local region of infrared spectra of semen celosiae and cockscomb *** difference of infrared spectra between semen celosiae and cockscomb flower is greatly *** rate is greatly improved. Daubechies wavelet is used as mother *** is implemented to the infrared spectra of semen celosiae and cockscomb *** difference between semen celosiae and cockscomb flower is observed at all scales in the continuous wavelet *** optimal scale is selected to identify semen celosiae and cockscomb *** results show that it is effective to apply CWT on the basis of FTIR to identify traditional Chinese medicinal materials,which are the same general but different species.

关键词： semen celosiate cockscomb flower FTIR CWT Chinese medical material

Modal identification of system driven by lévy random excitation based on continuous time AR model

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Science china(Technological Sciences) 2009年第12期52卷 3649-3653页

作者： DU XiuLi 1,2 &WANG FengQuan 1 1 college of Civil Engineering,Southeast university,Nanjing 210096,china 2 School of Mathematical Sciences,Nanjing normal university,Nanjing 210097,china college of Civil Engineering Southeast University Nanjing 210096 China School of Mathematical Sciences Nanjing Normal University Nanjing 210097 China

Based on the continuous time AR model,this paper presents a new time-domain modal identification method of LTI system driven by the uniformly modulated lévy random *** structural dynamic equation is first transformed into the observation equation and the state equation(namely,stochastic differential equation).Based on the property of the strong solution of the stochastic differential equation,the uniformly modulated function is identified *** by virtue of the Girsanov theorem,we present the exact maximum likelihood estimators of ***,the modal parameters are identified by eigen *** results show that the method not only has high precision and robustness but also has very high computing efficiency.

关键词： modal identification uniformly modulated function CAR model lévy process exact maximum likelihood estimator

Polyaniline Formed in Alkaline Solution─A New Luminous Material

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Chinese Chemical Letters 2000年第8期11卷 681-684页

作者： Nian Bing LI (college of chemistry and Chemical Engineering, Southwest china normal university, Chongqing 400715) Sheng Tao ZHANG, Pei Dao DING (college of chemistry and Chemical Engineering, Chongqing university, Chongqing 400044) SW china normal Univ Coll Chem & Chem Engn Chongqing 400715 Peoples R China Chongqing Univ Coll Chem & Chem Engn Chongqing 400044 Peoples R China

Electropolymerization of aniline in KOH solution and properties of the polymer are studied by using in situ reflex ellipsometry, cyclic voltammetry and fluorescence spectroscopic method. The change patterns of ellipsometric parameters and the thickness of film in the process of electropolymerization are investigated. The complex refractive indices and the fluorescence spectra of PAN indicate that the PAN is a new kind of luminous material.

关键词： Polyaniline electropolymerization alkaline solution luminous material.

α-Oxoketene Cyclic S, S-cetals chemistry-Substitution Reaction of α,α'-Dicinnamoyl Ketene Cyclic S, S-Acetals with Ethylenediamine

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Chinese Chemical Letters 1998年第3期9卷 231-232页

作者： Mei Xin ZHAO Qun LIU Fu Shun LIANG Jing Fu LIU Bao Zhong ZHAO LianZhong LI (Department of chemistry, Northeast normal university, Changchun, 130024)(Department of chemistry, jilin Teacher college, jilin, 13.000) NE normal Univ Dept Chem Changchun 130024 Peoples R China jilin Teacher Coll Dept Chem Changchun 131000 Peoples R China

α,α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α'-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yield under ... 详细信息

关键词： α,α'-dicinnamoyl ketene cyclic S,S-acetals ethylenediamine substitution reaction,α,α'-dicinnamoyl ketene cyclic N,N-acetals

Short cycle structures for graphs on surfaces and an open problem of Mohar and Thomassen

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Science china Mathematics 2006年第2期49卷 212-224页

作者： REN Han & DENG Mo Department of Mathematics, East china normal university, Shanghai 200062, china college of Mathematics & Information Science, Northwest normal university, Lanzhou 730070, china 1. Department of Mathematics East China Normal University Shanghai 200062 China 2. college of Mathematics & Information Science Northwest Normal University Lanzhou 730070 China

In this paper we investigate cycle base structures of a (weighted) graph and show that much information of short cycles is contained in an MCB (i.e., minimum cycle base). After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be an MCB. Furthermore, we show that the structure of MCB in a (weighted)graph is unique. The property is also true for those having a longest length (although much work has been down in evaluating MCB, little is known for those having a longest length). We use those methods to find out some unknown properties for short cycles sharing particular properties in (unweighted) graphs. As applications, we determine the structures of short cycles in an embedded graph and show that there exist polynomially bounded algorithms in finding a shortest contractible cycle and a shortest two-sided cycle provided such cycles exist. Those answer an open problem of B. Mohar and C. Thomassen.

关键词： cycle base facial cycle graph embedding.

Synthesis,characterization,structures and magnetic property of chiral oxalate-bridged dicopper(Ⅱ) complexes

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Science china chemistry 2010年第6期53卷 1255-1260页

作者： WU Ling1,WANG Jun2,ZHU CaiFei1,LIN YiJi1,CHEN LeiQi1,FAN Jun2 & ZHANG Hui1 1State Key Laboratory of Physical chemistry of Solid Surfaces Department of chemistry,college of chemistry and Chemical Engineering,Xiamen university,Xiamen 361005,china 2School of chemistry and Environment,South china normal university,Guangzhou 510006,china 1. State Key Laboratory of Physical chemistry of Solid Surfaces Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Environment South China Normal University Guangzhou 510006 China

The oxalato-bridged dicopper(II) complexes [Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2] (1),[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a),[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2] (2) and [Cu2(μ-ox)(LRR)(LSS)2(CH3COCH3)2(ClO4)2] (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2,2′-bipyridine,LSS = (8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine;ox2= oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was *** on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2 were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same *** crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear *** solution CD spectra of 1 and 2 in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and LSS,*** 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers *** exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.

关键词： dicopper(II) complex chiral bipyridine μ-oxalate bridge crystal structure CD spectroscopy magnetic property

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2, TANG Jun 2 , ZHANG AiHua 3 & JIA Ya 2 1 Department of Physics, Lanzhou university of Technology, Lanzhou 730050, china 2 Department of Physics, Central china normal university, Wuhan 430079, china 3 college of Electrical and Information Engineering, Lanzhou university of Technology, Lanzhou 730050, china 1. Department of Physics Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness