Composition of pseudo almost automorphic and asymptotically almost automorphic functions

This paper is concerned with pseudo almost automorphic functions, which are more general and complicated than pseudo almost periodic functions and asymptotically almost automorphic functions. New results, concerning the composition of pseudo almost automorphic functions, are established.     

THE SERRE RELATIONS IN RINGEL-HALL ALGEBRAS ABDUKADER OBUL

The author constructs the Casimir element of Hall algebras.By the method of Gabber-Kac theorem (see [4]),it is proved that the Serre relations are the defining relations in composition algebra.     

Hardy空间到加权Hardy空间上的复合算子

本文研究了从Hardy空间到加权Hardy空间上的复合算子,并给出此复合算子为有界和紧的条件。     

解析算子函数空间上的复合算子理论初步

本文将经典Hardy空间上复合算子的理论、方法应用到解析算子函数空间上,给出了解析算子函数空间的几个基本性质及复合算子的有界性条件.     

Singular values and Schmidt pairs of composition operators on the Hardy space

We find the singular values and corresponding Schmidt pairs of a compact composition operator Cφ induced by φ(z)=az+b, where |a|+|b|<1, on the classical Hardy space. We do so by solving a functional equation that is a generalization of Schröder's equation: find a function f, holomorphic on the open unit disc, and a complex number λ such that G(z)f(ψ(z))=λf(ψ(z)), where ψ is a holomorphic self-map of the open unit disc with an interior fixed point and G is a bounded holomorphic function on the open unit disc. In addition, we find the spectrum of the weighted composition operator MGCψ.     

RECa4O(BO3)3 thin films as new Luminescent materials screened by the combinatorial method

A new phosphor material, Y_1−xTb_xCa₄O(BO₃)₃ (0≤x≤1) film was grown on SiO₂ substrates by the combinatorial pulsed laser deposition (PLD) method, which enabled us to fabricate continuous composition spread film libraries. Photoluminescence (PL) and PL decay were measured for these film libraries to identify the optimum composition as well as to determine the luminescence mechanism. The film libraries showed strong dependence of luminescence intensities on the chemical composition of Tb ion. The optimum concentration of Tb ions in Y_1−xTb_xCa₄O(BO₃)₃ was experimentally and theoretically determined to be x=0.2-0.3.     

离子选择电极法测定N,N—二甲基膦酸基甘氨酸与钙的络合物组成和稳定常数

N,N—二甲基膦酸基甘氨酸[N,N—Bis(pheosphonomethyl)glycine,以下简称NBPG]结构式为在农业上作为植物生长调节剂,有明显的增糖增产作用。从化学结构上看,又是很好的络合剂。B.BynozkuHa等人曾研究过与Fe~(3+)、Mn~(2+)、Pb~(2+)的络合反应。本文用钙离子选择电极法测定了NBPG与Ca~(2+)生成络合物的组成和稳定常数;同时测定了NBPG的各级电离常数,为NBPG的开发应用奠定基础。     

COMPOSITION OPERATORS ON ANALYTIC VECTOR-VALUED NEVANLINNA CLASSES

Let φ be an analytic self-map of the complex unit disk and X a Banach space. This paper studies the action of composition operator Cφ： f→foφ on the vector-valued Nevanlinna classes N（X） and Na（X）. Certain criteria for such operators to be weakly compact are given. As a consequence, this paper shows that the composition operator Cφ is weakly compact on N（X） and Na（X） if and only if it is weakly compact on the vector-valued Hardy space H^1 （X） and Bergman space B1（X） respectively.     

The norm of a composition operator with linear symbol acting on the Dirichlet space

We obtain a representation for the norm of a composition operator on the Dirichlet space induced by a map of the form φ(z)=az+b. We compare this result to an upper bound for ‖Cφ‖ that is valid whenever φ is univalent. Our work relies heavily on an adjoint formula recently discovered by Gallardo-Gutiérrez and Montes-Rodríguez.     

Raman spectra and thermal analysis of a new lead–tellurium–germanate glass system

Differential scanning calorimetry (DSC) and Raman scattering studies of a new glass system, lead–tellurium–germanate glasses in the form of (90−x)GeO₂·xTeO₂·27PbO·10CaO with x=0, 10, 20, 30, and 40, are reported. The glass samples were fabricated using a conventional melt-quenching method. The Raman spectra and possible glass structures are discussed for different TeO₂ contents. The results indicate that increasing TeO₂ content up to 40 mol% in the glass system decreases the glass transition temperature and melting temperature, and suppresses the crystallization tendency in the fiber pulling temperature range. The lead–tellurium–germanate glass, GTPC, possesses a larger refractive index and a smaller maximum phonon energy than that of a lead–germanate glass, 63GeO₂·27PbO·10CaO, and shows a better thermal stability compared to a tellurite glass, 75TeO₂·20ZnO·5Na₂O (TZN). These improved properties could be beneficial for fabricating rare-earth doped fiber devices.