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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.
Let E be a complete, barrelled locally convex space, let V = (vn) be an increasing sequence of strictly positive, radial, continuous, bounded weights on the unit disc 𝔻 of the complex plane, and let φ be an analytic self map on 𝔻. The composition operators Cφ : f → f ○ φ on the weighted space of holomorphic functions HV (𝔻, E) which map bounded sets into relatively weakly compact subsets are characterized. Our approach requires a study of wedge operators between spaces of continuous linear maps between locally convex spaces which extends results of Saksman and Tylli [31, 32], and a representation of the space HV (𝔻, E) as a space of operators which complements work by Bierstedt , Bonet and Galbis [4] and by Bierstedt and Holtmanns [6]. 相似文献
117.
118.
鲁北地区人体结石的成分及成因分析 总被引:4,自引:0,他引:4
采用X射线衍射(XRD)、红外光谱(IR)和扫描电子显微技术(SEM)对鲁北地区22例手术取出的人体结石标本进行了分析。用原子吸收光谱分析(AAS)对鲁北地区饮用水中的微量元素进行了测定。结果表明鲁北地区的人体胆结石主要有胆固醇结石、胆色素结石和泥砂质结石,其中以泥砂质结石较多,未发现混合结石。该地区尿路结石中,上尿路(肾、输尿管)结石以草酸钙、尿酸结石为主,下尿路(膀胱)结石以鸟粪石(六水磷酸镁氨)、羟基磷灰石为主,未发现尿道结石。该地区的人体结石的形成与当地的环境和水质有关。 相似文献
119.
《Physics letters. A》2020,384(32):126795
The effects of diameter variation as a result of composition modulation along a nanowire on the confined energy states of electrons have been investigated theoretically. Possible confined states have been predicted by examining an effective potential term. Our results indicate that for a given radius of the wire, there exists a critical radius for modulation part below which carriers could not bound to the modulated part. The critical radius increases and reaches a limiting value as wire radius increases, specifying that the bound states could survive even when the radius of modulation decreases below the radius of remaining wire. Also, application of magnetic field could affect the critical radius so that the confinements to the modulated part are suppressed gradually by increasing the field strength, which is a sign of type-I to type-II transitions. Examination of results by the numerically solving the Schrodinger equation confirms the analytical predictions. 相似文献
120.
JI Zhi Abraham F. Jalbou LI Jun-Qian 《结构化学》2007,26(7):843-849
Density functional theory periodic slab calculations were carried out for CO adsorption on a series of Mo modified Pt(111) surfaces to provide an insight into the interaction between CO and doped metal surface, an important issue in CO oxidation as well as in promotion and poisoning effects of catalysis. The modification of adsorption properties with respect to those of adsorption on the pure Mo(110) and Pt(111) is described in terms of changes in the adsorption energies, adsorption sites and vibrational properties occurring upon alloying. We believe that the present DFT calculations can provide important information into optimal alloy composition for CO-tolerance, which is not easily obtained by experimental methods. 相似文献