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111.
Choonkil BAAK 《数学学报(英文版)》2006,22(6):1789-1796
Let X, Y be vector spaces. It is shown that if a mapping f : X → Y satisfies f((x+y)/2+z)+f((x-y)/2+z=f(x)+2f(z),(0.1) f((x+y)/2+z)-f((x-y)/2+z)f(y),(0.2) or 2f((x+y)/2+x)=f(x)+f(y)+2f(z)(0.3)for all x, y, z ∈ X, then the mapping f : X →Y is Cauchy additive.
Furthermore, we prove the Cauchy-Rassias stability of the functional equations (0.1), (0.2) and (0.3) in Banach spaces. The results are applied to investigate isomorphisms between unital Banach algebras. 相似文献
112.
徐能 《数学物理学报(A辑)》2011,31(1):216-228
该文引进和研究了一类含有Dziok-Srivastava算子的新的多叶解析函数. 得到了这一函数类中的一些有趣的性质, 如包含关系, 卷积性质等. 这些结果改进和拓展了早期的一些工作. 同时也得到了其他一些新的结果. 相似文献
113.
114.
S.H. Kulkarni 《Linear algebra and its applications》2010,432(11):3012-3017
Aim of this short note is to obtain a formula for the gap between two densely defined unbounded closed operators. It is interesting to note that the formula is very similar to the corresponding formula for the gap between two bounded operators. 相似文献
115.
116.
The mean first passage time of a three-level atomic optical bistable system subjected to noise
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The transient properties of a three-level atomic optical bistable system in the presence of multiplicative and additive noises are investigated. The explicit expressions of the mean first-passage time (MFPT) of the transition from the high intracavity intensity state to the low one are obtained by numerical computations. The impacts of the intensities of the multiplicative noise D M and the additive noise D A , the intensity of correlation between two noises λ , and the intensity of the incident light y on the MFPT are discussed, respectively. Our results show: (i) for the case of no correlation between two noises (λ = 0.0), the increase in D M and D A can lead to an increase in the probability of the transition to the low intracavity intensity state, while the increase in y can lead to a retardation of the transition; and (ii) for the case of correlation between two noises (λ = 0.0), the increase in λ can cause an increase in the probability of the transition, and the increase in D A can cause a retardation of the transition firstly and then an increase in the probability of the transition, i.e., the noise-enhanced stability is observed for the case of correlation between two noises. 相似文献
117.
George Voutsadakis 《代数通讯》2013,41(1):271-280
Pa?asińska and Pigozzi developed a theory of partially ordered varieties and quasi-varieties of algebras with the goal of addressing issues pertaining to the theory of algebraizability of logics involving an abstract form of the connective of logical implication. Following their lead, the author has abstracted the theory to cover the case of algebraic systems, systems that replace algebras in the theory of categorical abstract algebraic logic. In this note, an order subdirect representation theorem for partially ordered algebraic systems is proven. This is an analog of the Order Subdirect Representation Theorem of Pa?asińska and Pigozzi, which, in turn, generalizes the well-known Subdirect Representation Theorem of Universal Algebra. 相似文献
118.
采用水热法合成了负载K的纳米片状水滑石衍生CoAlO金属氧化物,其表现出优异的催化碳烟燃烧活性.氢气-程序升温还原(H2-TPR)实验结果表明,K与Co之间的相互作用提高了催化剂的氧化还原性能.X射线光电子能谱(XPS)分析结果表明,K的负载增大了表面Co2+/Co3+的比例,促进了氧空位的产生,提高了催化剂对气相氧的吸附能力.碳烟-程序升温还原(Soot-TPR)实验结果表明,K的负载增加了表面吸附氧数量.动力学实验结果表明,K的负载增加了单位质量催化剂上的活性氧数量、反应速率和转化频率(TOF),从而提高了催化剂的本征活性.另外,碳烟颗粒可以分散在纳米片的层间,与活性位点的接触效率得到提高,也有利于提高催化碳烟燃烧活性. 相似文献
119.
Marjan Matvejchuk 《Proceedings of the American Mathematical Society》1998,126(4):1155-1164
Let be a real -algebra of -real bounded operators containing no central summand of type in a complex Hilbert space with conjugation . Denote by the quantum logic of all -orthogonal projections in the von Neumann algebra . Let be a probability measure. It is shown that contains a finite central summand and there exists a normal finite trace on such that , .
120.
C. Bernard-Henriet J. Jaud A. Baldy J. M. Mattalia M. Chanon 《Journal of chemical crystallography》1997,27(8):485-488
The crystal of 5-phenyl-2-endo-(propane-2-sulfonyl)-bicyclo[2-2-1]hept-5-ene-2-carbonitrile1, a new radical-clock is described. The structure has confirmed the configuration for the positions of the phenyl and sulfonyl
groups. In the crystal, the radical precursor carbon atom of the propane group is not neighbouring with the double bond of
the norbornene. Nevertheless, in solution, it may be expected an ideal conformation with a short intergroup distance leading
to a cyclization process. Crystal data: C17H19NO2S, triclinic, space group P−1,a=6.567 (3),b=10.407(5),c=12.610(6), α=110.48(2), β=95.88(2), λ=102.67(3). 相似文献