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51.
SOLUTIONSFORASYSTEMOFNONLINEARRANDOMINTEGRALANDDIFFERENTIALEQUATIONS¥DingXieping(丁协平)WangFan(王凡)(DepartmentofMathematics,Sich... 相似文献
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Ambrish Kumar Srivastava Neeraj Misra 《International journal of quantum chemistry》2014,114(5):328-332
Density functional calculations on the ground state geometries and stabilities of PdOn species (n = 1–5) are performed in neutral as well as anionic forms. Calculations reveal that Pd can bind stably with four O atoms indicating the maximum oxidation state of Pd as high as +8. The electron affinities of PdOn suggest that these species behave as superhalogens for n ≥ 2. The large electron affinities of PdOn species along with stability of their anions point toward the synthesis of new class of compounds having unusual oxidizing capabilities. This possibility is explored by considering the interaction of PdO2 superhalogen with Ca atom which forms a stable CaPdO2 complex. In this complex, PdO2 unit closely mimics the behavior of O atom when compared with CaO molecule. © 2013 Wiley Periodicals, Inc. 相似文献
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Pregnane oligoglycoside, namely roylinine, and a pregnane derivative, namely marsgenin, have been isolated from chloroform-soluble extract of dried stem of Marsdenia roylei, and their structures were determined using 1H-NMR, 13C-NMR, 1H-1H COSY, HSQC, TOCSY and FABMS spectral techniques as well as chemical degradation and derivatisation. 相似文献
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This paper is concerned about a reaction-diffusion equation on n-dimensional isotropically growing domain, which describes the insect dispersal. The model for growing domains is first derived, and the comparison principle is then presented. The asymptotic behavior of the solution to the reaction-diffusion problem is given by constructing upper and lower solutions. Our results show that the growth of domain takes a positive effect on the asymptotic stability of positive steady state solution while it takes a negative effect on the asymptotic stability of the trivial solution. Numerical simulations are also performed to illustrate the analytical results. 相似文献
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The general block ST decomposition of the saddle point problem is used as a preconditioner to transform the saddle point problem into an equivalent symmetric and positive definite system. Such a decomposition is called a block ST preconditioner. Two general block ST preconditioners are proposed for saddle point problems with symmetric and positive definite (1,1)-block. Some estimations of the condition number of the preconditioned system are given. The same study is done for singular (1,1)-block. 相似文献
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An ordered analogue of quadruple systems is tetrahedral quadruple systems. A tetrahedral quadruple system of order v and index λ, TQS(v, λ), is a pair (S, T){(S, \mathcal{T})} where S is a finite set of v elements and T{\mathcal{T}} is a family of oriented tetrahedrons of elements of S called blocks, such that every directed 3-cycle on S is contained in exactly λ blocks of T{\mathcal{T}} . When λ = 1, the spectrum problem of TQS(v, 1) has been completely determined. It is proved that a TQS(v, λ) exists if and only if λ(v − 1)(v − 2) ≡ 0 (mod 3), λv(v − 1)(v − 2) ≡ 0 (mod 4) and v ≥ 4. 相似文献
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建立了一般增长区域上的反应扩散模型,并给出了定义在一种特殊的一维增长区域上的Lengyel-Epstein系统发生Truing不稳定的条件,结论表明如果区域增长速度的散度为零,那么这种变化对系统的稳定性没有影响. 相似文献