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51.
Gd3(SeO3)4F: A Fluoride Selenite with μ3‐SeO32– and μ3‐F– Capped Gd3 Rings The decomposition of Gd2(SeO4)3 in the presence of LiF in sealed gold ampoules yields single crystals of Gd3(SeO3)4F (hexagonal, P63mc, Z = 2, a = 1044.3(1), b = 694.32(7) pm, Rall = 0.0286). In the crystal structure one SeO32– group and one F– ion cap a ring of three Gd atoms. Furthermore, the crystal structure is strongly influenced by the lone pairs of the SeO32– ions. 相似文献
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Pure anatase-TiO2 and/or titanate nanotubes, photochromic Ag loaded titanium dioxide nanotubes (TNTs) and AgCl loaded titanate nanotubes were synthesized by hydrothermal method. The pH value during the neutralization process plays a crucial role in controlling the morphology and composition of the nanotubes. All these nanotubes were confirmed by XRD, TEM, EDS and XPS analysis. Most of them have open ends with inner/outer diameters of 7/10 nm and several hundred nanometers in length. For photochromic behavior in the case of AgCl-titanate nanotubes, the red color can be clearly observed after irradiation by red light, while the yellow, green, blue ones displayed pale black after the corresponding irradiation. On the other hand, Ag loaded TNT sample exhibited multicolor photochromism corresponding to that of incident light. The photoreduction of silver halide to Ag particle in the case of loaded AgCl particles and a particle-plasmon-assisted electron transfer from Ag nanoparticles to TiO2 in the case of loaded Ag particles are considered to be responsible for this different behavior. 相似文献
54.
The ruthenium(II)-supported heteropolyanions [HXW7O28Ru(dmso)3]6-(X=P, 1; As, 2) are composed of a Ru(dmso)3 group attached to an unprecedented heptatungstate fragment via two Ru-O-W bonds and one Ru-O-X bond, which represents a fundamentally novel mode of Ru-coordination to a polyoxoanion framework. Multinuclear 183W, 31P, 13C, and 1H NMR studies indicate high stability of 1 and 2 in solution. 相似文献
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Thalictoside (I), a novel glycoside containing a nitro group, has been isolated from Thalictrum aquilegifolium and the structure has been established by chemical transformations, spectral analysis and synthesis. 相似文献
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Peter G. Jones Ludger Ernst Ina Dix Lars Wittkowski 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):239-241
The [2.2]paracyclophane groups of the title compounds, chiral and meso‐bis(tricyclo[8.2.2.24,7]hexadeca‐4,6,10,12,13,15‐hexaen‐5‐yl)methane (the former as a racemate), C33H32, and meso‐bis(tricyclo[8.2.2.24,7]hexadeca‐4,6,10,12,13,15‐hexaen‐5‐yl) sulfide, C32H30S, show the characteristic structural features of the parent compound [2.2]paracyclophane and the related compound dimethylbis([2.2]paracyclophan‐4‐yl)silane, C34H36Si: the aromatic rings are puckered, resulting in a boat conformation. The planes of the four coplanar C atoms are slightly twisted with respect to each other. The Csp3—Csp3 bond lengths of the ethylene bridges are elongated by the electronic and steric effects of the skeleton. 相似文献
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In a recent paper, Hsieh and Liu (2010) consider quality investment and inspection strategies of one supplier and one manufacturer. They propose solutions of four non-cooperative game models with different degrees of information available about the players’ inspection sampling rates and quality investments. For the two most comprehensive scenarios, we show that these (interior) solutions do not always represent the optimal solutions, as the boundary solutions lead to considerably higher profits. Furthermore, we propose modified algorithms providing the optimal solutions by including the boundary solutions into the consideration. 相似文献
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