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111.
The boundedness and compactness of the products of differentiation and composition operators from Zygmund spaces to Bloch spaces and Bers spaces are discussed in this paper. 相似文献
112.
G. Lechner D. Li H. Queffélec L. Rodríguez-Piazza 《Journal of Functional Analysis》2018,274(7):1928-1958
We study the approximation numbers of weighted composition operators on the Hardy space on the unit disc. For general classes of such operators, upper and lower bounds on their approximation numbers are derived. For the special class of weighted lens map composition operators with specific weights, we show how much the weight w can improve the decay rate of the approximation numbers, and give sharp upper and lower bounds. These examples are motivated from applications to the analysis of relative commutants of special inclusions of von Neumann algebras appearing in quantum field theory (Borchers triples). 相似文献
113.
We provide an alternative proof to those by Shkarin and by Bayart and Matheron that the operator D of complex differentiation supports a hypercyclic algebra on the space of entire functions. In particular we obtain hypercyclic algebras for many convolution operators not induced by polynomials, such as , , or , where . In contrast, weighted composition operators on function algebras of analytic functions on a plane domain fail to support supercyclic algebras. 相似文献
114.
115.
Kateryna V. Terebilenko Igor V. Zatovsky Nikolay S. Slobodyanik Konstantin V. Domasevitch Denis V. Pushkin Vyacheslav N. Baumer Valentina S. Sudavtsova 《Journal of solid state chemistry》2007,180(12):3351-3359
Phase equilibrium in the pseudo-quaternary system K2O–MoO3–P2O5–Bi2O3 was studied as three-component solvent K2MoO4–KPO3–MoO3 containing 15 mol% Bi2O3 during slow cooling and spontaneous crystallization. The results of the investigation were shown on a composition diagram, which indicates the crystallization fields of K2Bi(PO4)(MoO4), K5Bi(MoO4)4, BiPO4 and K3Bi5(PO4)6. New phosphate K3Bi5(PO4)6 was characterized by single-crystal X-ray diffraction (space group C2/c, a=17.680(4), b=6.9370(14), c=18.700(4) Å, β=113.79(3)°) and FTIR spectroscopy. The possibility of lone electron pair stereoactivity of bismuth was suggested using the calculations of characteristics of the Voronoi–Dirichlet polyhedra for K3Bi5(PO4)6 and K2Bi(PO4)(MoO4). 相似文献
116.
Weighted aggregation of fuzzy preference relations on the set of alternatives by several criteria in decision-making problems
is considered. Pairwise comparisons with respect to importance of the criteria are given in fuzzy preference relation as well.
The aggregation procedure uses the composition between each two relations of the alternatives. The membership function of
the newly constructed fuzzy preference relation includes t-norms and t-conorms to take into account the relation between the
criteria importance. Properties of the composition and new relation, giving a possibility to make a consistent choice or to
rank the alternatives, are proved. An illustrative numerical study and comparative examples are presented. 相似文献
117.
Chaturaporn Nimjaroen Shigeki Morimoto Chaiyot Tangsathitkulchai 《Journal of Non》2009,355(34-36):1737-1741
The porous glasses were prepared by a conventional phase separation method using coal fly ash as a raw material, and the properties of these porous glasses were investigated. The composition of coal fly ash is basically composed of SiO2–Al2O3–Fe2O3–CaO system and the SiO2–B2O3–Al2O3–CaO–Na2O system of glass was chosen as base glass composition. The pore diameter increases proportional to cube root of heating time (t1/3), however, the early stage of phase separation is not clear. It is estimated that the rate determining step may be the diffusion process of structural units involving oxygen ions and the phase separation may take place by the nucleation and growth mechanism, and the relatively larger pores of above 1 μm can be obtained easily. The chemical composition of porous glasses is SiO2–B2O3–Al2O3(–CaO–Na2O). A relatively large amount of fly ash (>40%) can be used successfully for the preparation of porous glass. 相似文献
118.
Helge Glöckner 《Mathematische Zeitschrift》2008,260(4):889-904
Let G be a Lie group over a local field of characteristic p > 0 which admits a contractive automorphism α : G → G (i.e., α
n
(x) → 1 as n → ∞, for each x ∈ G). We show that G is a torsion group of finite exponent and nilpotent. We also obtain results concerning the interplay between contractive
automorphisms of Lie groups over local fields, contractive automorphisms of their Lie algebras, and positive gradations thereon.
Some of the results extend to Lie groups over arbitrary complete ultrametric fields.
Supported by the German Research Foundation (DFG), grants GL 357/2-1 and GL 357/6-1. 相似文献
119.
Summary Against the background of the experimental reports obtained so far some very recent theoretical approaches to the understanding
of the exotic family events in cosmic-ray physics have been traced in a comprehensive manner. The main trends in the observations
have been highlighted and the limitations of the theoretical attempts have been pointed out. 相似文献
120.
借多波长量测数据测定二元配合物组成 总被引:1,自引:0,他引:1
本文提出利用多波长量测数据测定二元配合物组成的新方法。首先以线性最小二乘求得各吸收组分吸收系数;继而应用多元线性回归获取各组分平衡浓度并据物料平衡求得配合物组成比及稳定常数。运用单纯形方法对5个体系测定结果进行了检验。 相似文献