排序方式: 共有70条查询结果,搜索用时 31 毫秒
21.
Lian Fa HE College of Mathematics Information Science Hebei Normal University Shijiazhuang P.R.ChinaJin Feng LV Hebei Normal University of Science & Technology Qinhuangdao P.R.China Li Na ZHOU College of Mathematics Information Science Hebei Normal University Shijiazhuang P.R.China 《应用数学学报(英文版)》2004,(4)
We introduce a new definition of measure-theoretic pressure for ergodic measures of con-tinuous maps on a compact metric space.This definition is similar to those of topological pressureinvolving spanning sets.As an application,for C~(1 α)(α>0) diffeomorphisms of a compact manifold,we study the relationship between the measure-theoretic pressure and the periodic points. 相似文献
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给出并证明了Bernstein—Kantorovich算子逆中插式的B型强逆不等式,即存在l,使得ω_φ~(2r)(f,1/n~(1/2))≤C(||k_n~((2r-1))f-f||_∞+||K_(ln)~((2r-1))f-f||_∞). 相似文献
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Ce:KNSBN晶体衍射特性研究 总被引:1,自引:0,他引:1
在非同时读出条件下测量了Ce:KNSNB晶体两波耦合体光栅衍射效率随写入光强比、写入光偏振态和写入光夹角的变化关系,并与同时读出条件下衍射效率变化规律的测量结果进行了比较,发现二者基本一致.利用耦合波理论对实验结果进行了理论分析和拟合,拟合结果和实验数据较好的吻合. 相似文献
24.
Guo Liang Feng 《中国化学快报》2010,21(9):1057-1061
<正>An efficient synthesis of symmetrical 2,2-bis(1H-indol-3-yl)-2H-acenaphthen-1-one is achieved via a reaction of acenaphthe-nequinone and indoles catalyzed by solid superacid SO_4~(2-)/TiO_2 under solvent-free conditions at room temperature by grinding, which provides an efficient route to the synthesis of symmetrical 2,2-bis(1H-indol-3-yl)-2H-acenaphthen-1-one.This procedure offers several advantages including solvent-free conditions,excellent yields of products,simple work-up as well as reuse of catalysts which makes it a useful and attractive protocol for the synthesis of these compounds. 相似文献
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ZHANG YunNan LIN LiQiong & ZHONG HuaiJie School of Mathematics Computer Science Fujian Normal University Fuzhou China Mathematics Information Science College Hebei Normal University Shijiazhuang College of Mathematics Computer Science Fuzhou University Fuzhou 《中国科学 数学(英文版)》2011,(4)
This paper studies the structure of operators on Σ1e type Banach spaces.It solves the problem of the small compact perturbations of operators with connected spectra.Namely,it shows that every operator with a connected spectrum on separable Σ1e type Banach spaces is a small compact perturbation of a strongly irreducible operator.Based on this result,this paper establishes the approximate Jordan forms of operators on Σ1e type Banach spaces with Schauder bases. 相似文献
27.
Simultaneous determination of epinephrine(EP)and dopamine(DA)at 2,3-dimercaptosuccinic acid(DMSA)modified electrode was studied.The oxidation peaks of the mixture of EP and DA appeared at the same potential,but the cathodic peak currents were only linear to the concentration of DA,whereas the anodic peak currents were equal to the sum of individual anodic peak currents of EP and DA.Therefore,a novel electrochemical method for the simultaneous determination of EP and DA at a DMSA modified electrode(DMSA/A... 相似文献
28.
Two new C-glucoside oxanthrones,6-methoxyl-10-hydroxyaloin A(1) and 6-methoxyl-10-hydroxyaloin B(2),were isolated from the roots of Rumex gmelini Turcz.Their structures were elucidated on the basis of spectroscopic techniques and chemical means. 相似文献
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首先给出了复$k$-hypergenic函数的几个等价条件,其中包括广义的Cauchy-Riemann方程.其次给出了复$k$-hypergenic调和函数的几个等价条件.
最后讨论了复$k$-hypergenic函数和复$k$-hypergenic调和函数的关系.例如,已知一个复$k$-hypergenic调和函数$u(z)$,则局部存在复$k$-hypergenic
函数$f(z)$, 使得$P_0f(z)=u(z)$. 相似文献
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ZHU YuJun & ZHANG JinLian College of Mathematics Information Science Hebei Normal University Shijiazhuang China 《中国科学 数学(英文版)》2010,(2)
In this paper, the concept of Lyapunov exponent is generalized to random transformations that are not necessarily differentiable. For a class of random repellers and of random hyperbolic sets obtained via small perturbations of deterministic ones respectively, the new exponents are shown to coincide with the classical ones. 相似文献