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We prove that the restriction operator for the sublaplacian on the quaternion Heisenberg group is bounded from L p to L p if 1 ≤ p ≤ 4 3 . This is different from the Heisenberg group, on which the restriction operator is not bounded from L p to L p unless p = 1. 相似文献
23.
Zeng He-ping Wu Guang Wu E. Pan Hai-feng Zhou Chun-yuan F. Treussart J. -F. Roch 《Frontiers of Physics in China》2006,1(1):1-18
Unbreakable secret communication has been a dream from ancient time. It is quantum physics that gives us hope to turn this
wizardly dream into reality. The rapid development of quantum cryptography may put an end to the history of eavesdropping.
This will be largely due to the advanced techniques related to single quanta, especially infrared single photons. In this
paper, we report on our research works on single-photon control for quantum cryptography, ranging from single-photon generation
to single-photon detection and their applications. 相似文献
24.
WEN Li-Jun ZENG He-Ping 《有机化学》2003,23(Z1):124-124
In the search for intramolecular energy and electron transfer phenomena in [ 60 ] fullerene donor-containing molecules, some electron donor fragments have been covalently linked to the fullerene core. [1 ~4] Only in very fewcases has reliable evidence of thermal or photoinduced intramolecular electron transfer processes been reported. [5]With the aim of promoting an intramolecular electron transfer we sought to develop a novel type of 6-chlorophenazine derivative of [60]fullerene in which the 6-chloro-phenazine core is directly attached by two σ-bonds to the ball giving rise to a different and more rigid spatial orientation of the HOMO of the 6-chloro-phenazine addend with respect to the LUMO of [60]fullerene. 相似文献
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讨论了二维一阶线性变系数双曲方程的耗散谱元法,得到拟最优估计.数值结果表明,耗散谱元法对于具有较复杂边界条件的问题同样有效,对于有限光滑问题,耗散谱元法能够得到比传统的谱元法更好的结果. 相似文献
27.
The first stereoselective synthesis of Certonardolsterol D3 was described. Ene reaction and improved allylic oxidation were employed as key steps for efficient construction of the desired 3β,6α,15β-triol steroidal framework. The chiral side chain in Certonardolsterol D3 was finally introduced by Julia olefination. 相似文献
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由几何反演导出的分形几何 总被引:1,自引:0,他引:1
本文介绍了由几何反演而导出的自反分形概念.构造了一个对称的,分叉自反分形曲线和一个自反分形尘集.推广了分形密切的概念而且提出了一个新的概念——分形包络.最后给出了“肥皂”和“鸡蛋”的两个自反分形的实例. 相似文献
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Detailed structure of the attracting set of the piecewise linear Henon mapping(x, y)→(1- a|x|+by,x)with a=8/5 and b=9/25 is described in this paper using the method of dual line mapping. Let A and B denote the fixed saddles in the first quadrant, and in the third quadrant, respectively. It is claimed that(1)the attracting set is the closure of the unstable manifold of saddle B, which includes the unstable manifold of A as its subset, and(2)the basin of attraction is the closure of the stable manifold of A, bounded by the stable manifold of B, which is in the limiting set of the stable manifold of A.Relations of the manifolds of the periodic saddles with the manifolds of the fixed point are given. Symbolic dynamics notations are adopted which renders possible the study of the dynamical behavior of every piece of the manifolds and of every homoclinic or heteroclinic point. 相似文献