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61.
62.
Hybrid SnO2/nanocarbon families (graphene nanosheets (GNSs), single-wall carbon nanotubes (SWCNTs), multi-wall carbon nanotubes (MWCNTs) and carbon nanospheres (CNSs)) have been synthesized by a similar wet chemical method. SnO2 nanoparticles are uniformly loaded on the surface of the nanocarbon families. As lithium battery anodes, their electrochemical properties of the reaction of lithium are investigated under the same conditions. To compare between them, SnO2/GNSs have the largest capacity; SnO2/GNSs and SnO2/SWCNTs have high cyclability; and SnO2/MWCNTs can maintain the capacity at high current density. Such behaviors are ascribed to their surface-to-volume ratio, structure flexibility, ion mobility and electron conductivity. The present results are the bases for their practical applications in lithium-ion battery anodes.  相似文献   
63.
We show that a family F of functions holomorphic in a domain is normal, if for all ?F the derivative ?′ and ? share the value a(≠0) and if the set of values that ? (k+1) takes the zeros of ??a, is bounded. As an application we obtain some new uniqueness theorems of entire functions which improve the former results [Amer. H.H. Al-khaladi (2000). On a question of Yi-Yang. J. Shandong Univ., 35(3), 162–167; G. Jank, E. Mues and L. Volkmann (1986 Jank, G., Mues, E. and Volkmann, L. 1986. Meromorphic functionen die mit ihrer ersten und zweiten Ableitung einen endlichen wert teilen. Complex Variables, 6: 5171. [Taylor & Francis Online] [Google Scholar]). Meromorphic functionen die mit ihrer ersten und zweiten Ableitung einen endlichen wert teilen. Complex Variables, 6, 51–71; P. Li and C.C. Yang (2001). Uniqueness theorem on entire functions and their derivatives. J. Math. Anal. Appl., 253, 50–57; W. Lin (2001). Uniqueness theorem and normal criteria with sharing array. Math. Theory Appl., 21, 9–16 (Chinese); H.X. Yi and C.C. Yang (1995). Uniqueness Theory of Meromorphic Functions, Pure and Applied Math. Monographs No. 32. Science Press, Beiling; H. Zhong (1995). Entire functions that share one values with their derivatives. Kodai Math. J., 18, 250–259, etc].  相似文献   
64.
陈桂景 《数学学报》2000,43(5):833-842
为了克服在单参数双边截断型分布族中不能消除参数估计中在Bahardur意义下的超有效病态现象,本文提出了一种新的渐近效率.根据这种效率的定义,对一般 的参数函数,构造了适用的渐近中位无偏的渐近有效估计量.作为全文的理论基础,我们发现了渐近中位无偏估计的最优收敛速度.  相似文献   
65.
Lorenz系统族采样同步研究   总被引:4,自引:0,他引:4       下载免费PDF全文
金辉宇  奚宏生 《物理学报》2007,56(5):2488-2492
从对连续时间混沌系统进行数字测量的角度,提出了连续时间混沌系统的采样同步问题. 利用控制理论的结果,设计了Lorenz系统族的采样同步系统. 仅需测量一个状态分量,就可在采样时刻实现同步. 数值模拟例证了同步的性能. 关键词: 混沌同步 Lorenz系统族 采样同步  相似文献   
66.
Acharya  S.K. 《Queueing Systems》1999,31(3-4):207-216
This paper is concerned with the rate of convergence of the distribution of the maximum likelihood estimators of the arrival and the service rates in a GI/G/1 queueing system. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
67.
This paper introduces the concept of exceptional family for nonlinear variational inequality problems. Among other things, we show that the nonexistence of an exceptional family is a sufficient condition for the existence of a solution to variational inequalities. This sufficient condition is weaker than many known solution conditions and it is also necessary for pseudomonotone variational inequalities. From the results in this paper, we believe that the concept of exceptional families of variational inequalities provides a new powerful tool for the study of the existence theory for variational inequalities.  相似文献   
68.
We show that it is consistent with ZFC + ¬CH that there is a maxima a most disjoint permutation family A ⊆ Sym(ℕ)such that A is a proper subset of an eventually different family Eℕ and |A| < |E|. We also ask severa questions in this area.  相似文献   
69.
We study Tsirelson type spaces of the form T[(ℳ︁k, θk)lk=1] defined by a finite sequence (ℳ︁k)lk=1 of compact families of finite subsets of ℕ. Using an appropriate index, denoted by i(ℳ︁), to measure the complexity of a family ℳ︁, we prove the following: If i(ℳ︁k) < ω for all k = 1, …, l, then the space T[(ℳ︁k, θk)lk=1] contains isomorphically some lp, 1 < p < ∞, or c0. If i(ℳ︁) = ω, then the space T[ℳ︁, θ] contains a subspace isomorphic to a subspace of the original Tsirelson's space.  相似文献   
70.
In this paper, we consider the families of nearby singular diffeomorphism and the measure of a set in the parameter space, such that for each point of the set the corresponding diffeomorphism possesses strange attractor. For some families of one-dimensional mapping satisfying certain transversality condition, we prove that there is a positive measure set in the parameter space, such that the system in the corresponding families of nearly singular diffeomorphism has strange attractor. Furthermore, we study the dynamics of this type of strange attractor. Project Supported by Fund of National Science of China  相似文献   
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