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531.
本文构造了一种单模单参数q光场叠加态|Ψ>q=c(|α>q+β|0>q),利用Zhang等人提出的单模辐射场的振幅M次方压缩的定义对态|Ψ>q的压缩及高阶压缩特性进行了详细的研究.结果发现,在一定的条件下,态|Ψ>q可存在任意的M次方压缩效应. 最后,通过数值计算还详细研究了态|Ψ>q的压缩和平方压缩性质. 相似文献
532.
A Cu/Mn/ZrO2 methanol synthesis catalyst modified by Fischer-Tropsch (F-T) element (Ni,Co,Fe) was prepared by an coprecipatation method. The addition of F-T elements had a great effect on the catalyst performance. The higher alcohol selectivity increased greatly compared with that of the Cu/Mn/ZrO2 catalyst when nickel and cobalt were added, while the addition of iron improved the selectivity tohydrocarbon due to the interaction of the F-T element and the Cu/Mn/ZrO2 catalyst. 相似文献
533.
Miguel Yangari 《Integral Transforms and Special Functions》2017,28(12):953-965
In this paper, we deal with a new class of non-local operators that we term integro-differential systems of mixed type. We study the behaviour of solutions of this system when the diffusion term involves higher order fractional powers of the Laplacian. Moreover, we prove that the solution of the system decays faster than a power with an exponent given by the smallest index of the fractional power of the Laplacian. 相似文献
534.
We consider the strongly nonlinear boundary value problem,
where A is an elliptic operator of finite or infinite order. We introduce anisotropic weighted Sobolev spaces and we show under a
certain sign condition of the Carathéodory function g without assuming any growth restrictions, the existence of the weak solutions.
相似文献
535.
The high-order dispersive nonlinear Schrödinger equation is considered. The exact solutions were obtained by Zhang et al. [J.L. Zhang, M.L. Wang, X.Z. Li, Phys. Lett. A 357 (2006) 188-195] are analyzed. We can demonstrate that some solutions do not satisfy this equation. To obtain the correct solutions, the F-expansion method is applied to solve it. 相似文献
536.
Devrim Çakmak 《Applied mathematics and computation》2010,216(2):368-4871
In this paper, first we will give a short survey of the most basic results on Lyapunov inequality, and next we obtain this-type integral inequalities for certain higher order differential equations. Our results are sharper than some results of Yang (2003) [20]. 相似文献
537.
We model the roadway of a suspension bridge as a thin rectangular plate and we study in detail its oscillating modes. The plate is assumed to be hinged on its short edges and free on its long edges. Two different kinds of oscillating modes are found: longitudinal modes and torsional modes. Then we analyze a fourth order hyperbolic-like equation describing the dynamics of the bridge. In order to emphasize the structural behavior we consider an isolated equation with no forcing and damping. Due to the nonlinear behavior of the cables and hangers, a structural instability appears. With a finite dimensional approximation we prove that the system remains stable at low energies while numerical results show that for larger energies the system becomes unstable. We analyze the energy thresholds of instability and we show that the model allows to give answers to several questions left open by the Tacoma collapse in 1940. 相似文献
538.
Let L=L0+V be the higher order Schr?diger type operator where L0 is a homogeneous elliptic operator of order 2m in divergence form with bounded coeffi-cients and V is a real measurable function as mult... 相似文献
539.
In this paper, the authors give a new proof of Block and Weinberger’s Bochner vanishing theorem built on direct computations in the K-theory of the localization algebra. 相似文献
540.
We compute the parameters of the linear codes that are associated with higher dimensional projective embeddings of Grassmannian when the degree exceeds the number of elements of the finite field. We investigate various dimension formulas for the projective Reed-Müller codes. We show that the duals of higher Grassmann codes are given by higher Grassmann codes or their simple extensions. 相似文献