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991.
The authors obtain a holomorphic Lefschetz fixed point formula for certain non-compact “hyperbolic” Kǎihler manifolds (e.g. Kǎihler hyperbolic manifolds, bounded domains of holomorphy) by using the Bergman kernel. This result generalizes the early work of Donnelly and Fefferman. 相似文献
992.
993.
994.
In this paper, we give a definition of Bloch mappings defined in the unit polydisk D
n
, which generalizes the concept of Bloch functions defined in the unit disk D. It is known that Bloch theorem fails unless we have some restrictive assumption on holomorphic mappings in several complex
variables. We shall establish the corresponding distortion theorems for subfamilies β(K) and β
loc(K) of Bloch mappings defined in the polydisk D
n
, which extend the distortion theorems of Liu and Minda to higher dimensions. As an application, we obtain lower and upper
bounds of Bloch constants for various subfamilies of Bloch mappings defined in D
n
. In particular, our results reduce to the classical results of Ahlfors and Landau when n = 1.
This work was supported by the National Natural Science Foundation of China (Grant No. 10571164) and Specialized Research
Fund for the Doctoral Program of Higher Education (SRFDP) (Grant No. 20050358052) 相似文献
995.
996.
Xiong Huang 《Tetrahedron letters》2010,51(50):6637-6640
The first highly regio-, chemo-, and enantio-selective direct vinylogous Michael addition of 3-cyano-4-methylcoumarin derivatives to α,β-unsaturated ketones is described, employing readily available 9-amino-9-deoxy-epiquinine as the iminium organocatalyst. 相似文献
997.
A new potassium lithium double salt of decavanadate, K4Li2[V10O28]·10H2O ( 1 ) has been synthesized and characterized. 1 crystallizes in the triclinic system, and features an unusual (6,8)‐connected network with the K4O32 clusters, Li2O10 clusters and V10O28 clusters. The K4O32 clusters and Li2O10 clusters share an edge and a triangle plane to form an infinite rod‐shaped chain. The chains are further interlinked by V10O28 clusters to generate the final 3D framework. UV‐Vis spectrum, fluorescent spectrum and cyclic voltammetry curves have been studied. 相似文献
998.
1 INTRODUCTION Much attention has been paid to 1D, 2D and 3D coordination polymers because they can meet the need of functional materials with desired structures and properties[1~5]. One strategy in the design and synthesis of coordination architectures is the buil- ding-block approach. Commonly, bi- or multidentate organic ligands containing N[6, 7] or O[8, 9] atoms have ever been used in the construction. In our cur- rent work, we have selected melamine ligand as the main building bl… 相似文献
999.
A proper vertex coloring of a graph G is linear if the graph induced by the vertices of any two color classes is a union of vertex-disjoint paths. The linear chromatic number of G is the smallest number of colors in a linear coloring of G.Let G be a graph with maximum degree Δ(G). In this paper we prove the following results: (1) ; (2) if Δ(G)≤4; (3) if Δ(G)≤5; (4) if G is planar and Δ(G)≥52. 相似文献
1000.
Zhao Fangyuan Wang Fei Zhao Weining Zhou Jing Liu Yang Zou Lina Ye Baoxian 《Mikrochimica acta》2011,173(3-4):383-389
A facile, one-step and template-free method has been developed for the electrodeposition of well-dispersed platinum nanoparticles (Pt-NPs) on a glassy carbon electrode. The effects of various inorganic anions and overpotential on the morphologies and dimensions of the final products were investigated. The resulting Pt-NPs show high electrocatalytic activity towards methanol oxidation and are less easily poisoned by carbon monoxide. Figure
In this study, we have developed a simple, environmentally benign, controllable, and template-free method for the electrodeposition of monodispersed Pt NPs on a glassy carbon electrode. The resulting Pt NPs display high catalytic activity towards methanol oxidation, and are less easily poisoned by carbon monoxide. 相似文献