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121.
Journal of Mathematical Chemistry - Topological data analysis is a useful data analysis method that combines the mathematical theory of topology with computational methods to study the valuable... 相似文献
122.
123.
同族元素及化合物的性能与周期序数的关系 总被引:1,自引:0,他引:1
本文用周期序数的倒数 1 / n代表同族原子大体结构效应的因素 ,用公式 :P=a b/ n将同族元素及化合物的二十多种性能 (P)对 1 / n进行线性回归 ,得到良好结果。 相似文献
124.
Novel oxygen sensing materials consisting of [Ru(Bphen)2bpy]2+ (Bphen=4,7-diphenyl-1,10-phenanthroline, bpy=2,2′-bipyridyl) portion covalently grafted to the backbones of the ordered functionalized mesoporous MCM-41 are synthesized by co-condensation of tetraethoxysilane (TEOS) and the functionalized Ru(II) complex [Ru(Bphen)2Bpy-Si]2+ using surfactant cetyltrimethylammoniumbromide (CTAB) as template. The Bpy-Si was used as not only one of the precursors of the sol-gel process but also the second ligand of Ru(Bphen)2Cl2·2H2O complex to prepare the functionalized mesoporous materials for oxygen sensors. Dye leaching shortcoming is overcome due to the Si-C bonds. The derivative mesoporous oxygen sensing materials are characterized by Fourier transform infrared (FT-IR), small angle X-ray diffraction (SAXRD), luminescence intensity quenching Stern-Volmer plots, and excited-state decay analysis. The mesoporous materials show higher sensitivity to the O2 concentration in N2 (I0/I100=23.2) and shorter response time (1.2 s) in comparison with those based on sol-gel method. When the concentration of oxygen is 10%, the luminescence intensity of the oxygen sensor can be quenched by 89.9%, suggesting that it is highly sensing at low concentration of oxygen. 相似文献
125.
126.
Growth and optical properties of faceted hexagonal ZnO nanotubes 总被引:5,自引:0,他引:5
Tong Y Liu Y Shao C Liu Y Xu C Zhang J Lu Y Shen D Fan X 《The journal of physical chemistry. B》2006,110(30):14714-14718
Well-faceted hexagonal ZnO nanotubes were synthesized by a simple hydrothermal method and the subsequent aging process without any catalysts or templates. The formation of the tubular structure is closely linked to the polarity of ZnO and the selective adsorption behavior of Zn2+ amino complexes. The surface-related optical properties were studied with use of Raman and photoluminescence spectra. It was found that the oxygen vacancy-related visible emission intensity decreased while surface defect-related visible emission intensity increased when the nanotubes were annealed in oxygen ambient. The anomalous enhancement of PL integrated intensity with the temperature shows fairly high surface state density existing in ZnO nanotubes. 相似文献
127.
In this paper, we study the close relationship between multivariate coherent and convex risk measures. Namely, starting from a multivariate convex risk measure, we propose a family of multivariate coherent risk measures induced by it. In return, the convex risk measure can be represented by its induced coherent risk measures. The representation result for the induced coherent risk measures is given in terms of the minimal penalty function of the convex risk measure. Finally, an example is also given.
相似文献128.
129.
The photodegradation of doxorubicin (Dox) in the presence of hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) was studied; the degradation rate constant in the presence of HP‐β‐CD estimated by Lineweaver‐Burk analysis was approximately three times lower than that of free Dox aqueous solution, which shows that HP‐β‐CD can enhance the photostability of doxorubicin aqueous solution. The enhancement may be attributed to the inclusion interaction between HP‐β‐CD and doxorubicin. The characterization of FTIR, DSC, XRD and fluorescence titration indicates that 1:1 inclusion complex is formed between HP‐β‐CD and doxorubicin. 相似文献
130.
刘艳红 《数学物理学报(B辑英文版)》2010,30(1):47-54
We investigate the decay rates of the planar viscous rarefaction wave of the initial-boundary value problem to scalar conservation law with degenerate viscosity in several dimensions on the half-line space, where the corresponding one-dimensional problem admits the rarefaction wave as an asymptotic state. The analysis is based on the standard L2-energy method and L1-estimate. 相似文献