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1.
SiO2-supported Ni-Mo bimetallic phosphides were prepared by temperature-programmed reduction(TPR) method from the phosphate precursors calcined at different temperatures. Their properties were characterized by means of ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS), H2temperature-programmed reduction(H2-TPR), X-ray diffraction(XRD), transmission electron microscopy(TEM), CO chemisorption, H2 and NH3temperature-programmed desorptions(H2-TPD and NH3-TPD). Their catalytic performances for the deoxygenation of methyl laurate were tested in a fixed-bed reactor. When the precursors were calcined at 400 and 500?C, respectively, Ni Mo P2 phase could be formed apart from Ni2 P and Mo P phases in the prepared C400 and C500 catalysts. However, when the precursors were calcined at600, 700 and 800°C, respectively, only Ni2 P and Mo P phases could be detected in the prepared C600, C700 and C800 catalysts. Also, in C400, C500 and C600 catalysts, Mo atoms were found to be entered in the lattice of Ni2 P phase, but the entering extent became less with the increase of calcination temperature. As the calcination temperature of the precursor increased, the interaction between Ni and Mo in the prepared catalysts decreased, and the phosphide crystallite size tended to increase, subsequently leading to the decrease in the surface metal site density and the acid amount. C600 catalyst showed the highest activity among the tested ones for the deoxygenation of methyl laurate. As the calcination temperature of the precursor increased, the selectivity to C12 hydrocarbons decreased while the selectivity to C11 hydrocarbons tended to increase. This can be mainly attributed to the decreased Ni-Mo interaction and the increased phosphide particle size. In sum, the structure and performance of Ni-Mo bimetallic phosphide catalyst can be tuned by the calcination temperature of precursor.  相似文献   
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基于质谱的蛋白质组学在近20年有巨大的发展。在其应用中,病原微生物和与感染相关的蛋白质组学具有重要科学意义,体系复杂度又相对较小,一直受到广泛关注并有较快发展。本文从感染中病原微生物和宿主的蛋白质组学两方面入手,简要综述应用蛋白质组学研究感染过程的相关工作,着重介绍该领域近几年的主要进展,并对其发展做出展望。  相似文献   
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Two new interesting entangled structures, namely, [Ni1.5(L)(bpy)2(H2O)3] n · 3nH2O (I) and [Cd3(L)2(bbi)2]n · nH2O (II)(where H3L is 4-(4-carboxyphenoxy)-phthalic acid, bpy is 4,4′-bipyridine, and bbi is 1,1′-(1,4-butanediyl)bis(imidazole)) have been synthesized and characterized by elemental analysis (EA), infrared spectra (IR), X-ray powder diffraction (XRPD), solid fluorescence and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analysis revealed that complex I possesses a 3D self-penetrating framework constructed from ladder-like and fishbone-like subunits. Complex II shows a 3D framework of two-fold interpenetration assembled from trinuclear Cd(II) clusters bridged by bbi and L3? ligands.  相似文献   
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An olefin‐directed palladium‐catalyzed oxidative regio‐ and stereoselective arylation of allenes to afford 1,3,6‐trienes has been established. A number of functionalized allenes, including 2,3‐ and 3,4‐dienoates and 3,4‐dienol derivatives, have been investigated and found to undergo the olefin‐directed allene arylation. The olefin moiety has been proven to be a crucial element for the arylating transformation.  相似文献   
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A rhodium(III)‐catalyzed [3+2]/[5+2] annulation of 4‐aryl 1‐tosyl‐1,2,3‐triazoles with internal alkynes is presented. This transformation provides straightforward access to indeno[1,7‐cd]azepine architectures through a sequence involving the formation of a rhodium(III) azavinyl carbene, dual C(sp2) H functionalization, and [3+2]/[5+2] annulation.  相似文献   
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