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NianYuanTAN XiaoMingXIAO ZeLinLI TakekoMATSUMURA-INOUE 《中国化学快报》2004,15(6):687-690
A new cobalt(Ⅱ) complex with tridentate ligand 2, 6-bis (benzimidazol-2-yl)pyridine has been synthesized by microwave irradiation method and characterized by elemental analysis,electrochemical and spectral methods. The binding of the complex with calf thymus DNA has also been investigated by absorption and fluorescence spectra. 相似文献
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Zhang Zhongzhi Liu ChangrongSchool of Math. Science Central South Univ. Changsha China Dept. of Math. Hunan City Univ. Yiyang China. Faculty of Mathematics Econometrics Hunan Univ. Changsha China. 《高校应用数学学报(英文版)》2004,(3)
§1 IntroductionWe considerthe following inverse eigenvalue problem offinding an n-by-n matrix A∈S such thatAxi =λixi,i =1,2 ,...,m,where S is a given set of n-by-n matrices,x1 ,...,xm(m≤n) are given n-vectors andλ1 ,...,λmare given constants.Let X=(x1 ,...,xm) ,Λ=(λ1 ,λ2 ,...,λm) ,then the above inverse eigenvalue problemcan be written as followsProblem Given X∈Cn×m,Λ=(λ1 ,...,λm) ,find A∈S such thatAX =XΛ,where S is a given matrix set.We also discuss the so-called opti… 相似文献
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In this paper, a novel exact fixed-node quantum Monte Carlo (EFNQMC) algorithm was proposed, which is a self-optimizing and self-improving procedure. In contrast to the previous EFN-QMC method, the importance function of this method is optimized synchronistically in the diffusion procedure, but not be-fore beginning the EFNQMC computation. In order to optimize the importance function, the improved steepest descent tech-nique is used, in which the step size is automatically adjustable.The procedure is quasi-Newton type and converges super linear-ly. The present method also uses a novel trial function, which has correct electron-electron and electron-nucleus cusp condi-tious. The novel EFNQMC algorithm and the novel trial func-tion are employed to calculate the energies of 1 ^1A1 state of CH2, ^1Ag state of Cs and the ground-states of H2, LiH, Li2 and H2O. 相似文献
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A novel reaction of trimethylsilylated arylacetylenes with sulfonyl chlorides was performed in the presence of silver nitrate or triflate.Conjugated vinyl sulfones as dramatic products were obtained in moderate yields and with Z-selectivity.A free radical mechanism has been proposed to account for the formation of the products. 相似文献
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Tong Xiaojiao Zhou Shuzi Dept. of Appl.Math. Hunan Univ. Changsha . Dept.of Math. Changsha Univ.of Electric Power Changsha 《高校应用数学学报(英文版)》2000,(2)
§ 1 IntroductionIn this paper we study the following nonlinear equality constrained optimization prob-lem:minimize f(x) ,subjectto h(x) =0 ,(P)where h(x) =(h1 (x) ,h2 (x) ,...,hm(x) ) T,f and hi(i=1 ,2 ,...,m) are Rn→R twice conti-nously differentiable(m≤n) .Many authors have studied the problem(P) with trustregion method(see,references[1~ 3 ] ) .These methods have the same property:to enforce strict monotonicity for meritfunction at every iteration.Paper[4 ] shows thatstrictmonotonic … 相似文献
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CHEN YuJin SHI XiaoLing CAO MaoSheng & ZHU ChunLing School of Materials Science Engineering Beijing Institute of Technology Beijing China Micro-Nano Technologies Research Center Hunan University Changsha College of Science Harbin Engineering University Harbin College of Material Science Chemical Engineering 《中国科学G辑(英文版)》2009,(7)
CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (230 K) than that of the single bulk α-Fe2O3 materials (263 ... 相似文献
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利用以极大函数表示的有关Sobolev函数的逐点不等式来构造全局的Lipschitz型检验函数,得到了,在一定条件下,拟线性椭圆方程-div A(x,u,Du)=f(x)在grand Sobolev空间W_0~(θ,p)(Ω)中的很弱解是唯一的. 相似文献
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选用MRH-5A型环-块摩擦磨损试验机测定了3种载荷和2种转速条件下La2O3和WSi2增强MoSi2基复合材料在滑动干摩擦时的摩擦磨损性能,采用扫描电子显微镜分析了复合材料磨损表面形貌.结果表明:La2O3和WSi2增强MoSi2基复合材料的抗磨性能优于MoSi2及WSi2/MoSi2材料;当载荷与速度乘积(pv)值小于183.04N·m/s时,La2O3和WSi2增强MoSi2基复合材料的磨损质量损失仅为相同条件下MoSi2的1/4~1/6和WSi2/MoSi2的1/2;这是由于La2O3和WSi2复合增强相存在硬化和韧化协同作用所致;随着pv值增加,La2O3和WSi2增强MoSi2基复合材料依次呈现犁削、粘着磨损和疲劳磨损特征. 相似文献
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现代力学中的现代数学方法 总被引:1,自引:0,他引:1
本文简要介绍了力学与数学再次结合趋势的历史背景和现状。根据当代科学技术向力学提出的问题,简要综述了现代力学所涉及的现代数学领域和方法. 相似文献