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21.
In this paper, based on the utility preferential attachment, we propose a new unified model to generate different network topologies such as scale-free, small-world and random networks. Moreover, a new network structure named super scale network is found, which has monopoly characteristic in our simulation experiments. Finally, the characteristics ofthis new network are given.  相似文献   
22.
We study the probabilistic consequences of the choice of the basic number field in the quantum formalism. We demonstrate that by choosing a number field for a linear space representation of quantum model it is possible to describe various interference phenomena. We analyse interference of probabilistic alternatives induced by real, complex, hyperbolic (Clifford) and p‐adic representations.  相似文献   
23.
The coordination polymer {[Co(phth)(phen)(H2O)]·(C2H5OH)}n (phth = phthalate, phen = 1,10-phenanthroline) with formula C22H20CoN2O6 (Mr = 467.33) was synthesized by the solvothermal method under low temperature, and its crystal structure was determined by singlecrystal X-ray diffraction. The complex belongs to monoclinic system, space group P21/n with a =12.7352(16), b = 8.8125(11), c = 18.677(2) (A), β = 102.633(2)°, V = 2045.3(4) (A)3, Z = 4, Dc =1.518 g/cm3,μ = 0.882 mm-1, F(000) = 964, S = 1.053, the final R = 0.0401 and wR = 0.0984 for 3135 observed reflections (I > 2σ(I)). Single-crystal X-ray analysis revealed that the Co(Ⅱ) ion is six-coordinated. The cobalt complex forms a one-dimensional chain structure via phthalate bridging ligand. In the cobalt complex, a 3D network structure is formed by π-π stacking interaction of 1,10-phenanthroline as well as intermolecular hydrogen bonding interactions.  相似文献   
24.
By extending the notion of mixed states to functionals acting on the space of observables with diagonal singularity we obtain a well-defined complex spectral decomposition of the time evolution for a quantum decaying system. In this formalism, generalized Gamow states are obtained with well-defined physical properties.  相似文献   
25.
The mixed complex [Ni(L)(L')](ClO4)2 has been synthesized using 2-aminoethyl- bi(3-bi-aminopropyl)amine with phen (1,10-phenanthroline) in the presence of Ni(II) ion, and its structure was determined by X-ray diffraction. The crystal crystallizes in monoclinic, space group P21/c with a = 13.713(2), b = 13.1466(19), c = 14.780(2) (A), β = 97.620(3)°, V = 2640.9(7)(A)3, F(000) = 1272, Z = 4, Dc = 1.540 g/cm3, R = 0.0536 and wR = 0.1207. The Ni2+ ion is six- coordinated to furnish a distorted octahedral geometry.  相似文献   
26.
1 INTRODUCTION The self-assembly of organic-inorganic hybrid ma- terials is an intriguing area, which is yielding new generations of supramolecular architectures[1, 2]. Coor- dination by transition metals with multifunctional ligands is one of the main design principles. As a rigid multi-dentate ligand, 5-aminoisophthalic acid (AIP) has received considerable attention owing to the variety of bridging abilities[3~8]. It can engage in three types of intermolecular interactions: (1) M-L b…  相似文献   
27.
关联规则是数据挖掘中的重要研究内容之一,对在事务数据库不变,只对最小支持度和最小可信度进行改变的情况下,针对关联规则的维护问题,设计了一个增量式更新的改进算法AIUA。  相似文献   
28.
The synthesized 1-aryliminomethylenylnaphthalen-2-ol derivatives reacted with nickel chloride to form bis(1-aryliminomethylenylnaphthalen-2-oxy)nickel complexes. All resultant compounds were structurally characterized by elemental analyses, IR and H NMR, and the structures of the formed complexes were elucidated by X-ray crystal structure analysis. The complexes show high catalytic activities for the vinyl polymerization of norbornene in the presence of methylaluminoxane. The catalytic activity variations have been followed by gas chromatography through monitoring the conversion of norbornene.  相似文献   
29.
We study the infrared emission at 1.54 μm of an organolanthanide complex, Er(III)-tetraphenylporphyrin [Er(TPP)acac], both as a result of direct optical excitation and via energy transfer from host π-conjugate polymers of type poly(arylene–ethynylene) [PAE]. In the first case, the emission of the neat complex is characterized in inert transparent materials and a value of the quantum yield at 1.54 μm φIR=4×10−4 is measured. Then, fluorescence resonance transfer is investigated in blends of Er(TPP)acac with PAEs by monitoring the quenching of the polymer fluorescence along with the enhancement of both the visible emission of the ligand and the near-infrared band of Er3+. These different procedures allow a detailed analysis of the transfer efficiency within a specific implementation of the Förster model for polymeric donors. The experimental values of the critical radius R0, ranging from 1.3 to 2.5 nm for the different blends, are in good agreement with theory for a wide interval of the physical and spectroscopic parameters. This suggests that other mechanisms for excitation transfer do not play a significant role in these materials.  相似文献   
30.
Amphiphilic tris(2,2′‐bipyridine)ruthenium‐cored star‐shaped polymers consisting of one polystyrene block and two poly(N‐isopropylacrylamide) blocks were prepared by the “arm‐first” method in which RAFT polymerization and nonconvalent ligand–metal complexation were employed. The prepared amphiphilic star‐shaped metallopolymers are able to form micelles in water. The size and distribution of the micelles were studied by dynamic light scattering and transmission electron microscopy techniques. Preliminary studies indicate that the polymer concentration and the hydrophilic poly(N‐isopropylacrylamide) block length can affect the morphologies of the formed metal‐interfaced core–shell micelles in water. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4204–4210, 2007  相似文献   
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