Porous Pt-Fe bimetallic nanocrystals have been synthesized via self-assembly and can effectively facilitate the synthesis of 2-propanol from acetone. The bimetallic catalyst has three--dimensional channels and shows t...Porous Pt-Fe bimetallic nanocrystals have been synthesized via self-assembly and can effectively facilitate the synthesis of 2-propanol from acetone. The bimetallic catalyst has three--dimensional channels and shows turnover frequencies (TOFs) of up to 972 h^-1 for a continuous process more than 50 h. Preliminary mechanistic studies suggest that the high reactivity is related to the interface consisting of a bimetallic Pt-Fe alloy and Fe2O3-x. An understanding of real catalytic behavior and the catalytic mechanism based on model systems has been shown to help fabricate an improved Pt/Fe3O4 catalyst with increased activity and lifetime which has great potential for large-scale industrial applications.展开更多
Olefins find widespread applications in the synthesis of polyolefins and fine chemicals. With an increasing demand for olefins, the technologies for alkane dehydrogenation have drawn much attention. Several types of h...Olefins find widespread applications in the synthesis of polyolefins and fine chemicals. With an increasing demand for olefins, the technologies for alkane dehydrogenation have drawn much attention. Several types of heterogeneous catalysts have found applications in industry for the dehydrogenation of light alkanes, mainly ethane, propane, and butane. In the past three decades, a number of transition-metal complexes,particularly pincer-ligated iridium complexes, have been developed as the homogeneous catalysts for alkane dehydrogenations. The homogeneous catalyst systems operate under much milder conditions compared with the heterogeneous systems, and some systems exhibit good activity and high regioselectivity in dehydrogenation of alkanes longer than butane.展开更多
The effect of Cu addition on crystallization behavior and soft magnetic properties of Fe84-xP10C6Cux (x = 0-1.15) alloys was investigated. Low-cost FePCCu nanocrystalline alloys dispersed with ct-Fe phase with an av...The effect of Cu addition on crystallization behavior and soft magnetic properties of Fe84-xP10C6Cux (x = 0-1.15) alloys was investigated. Low-cost FePCCu nanocrystalline alloys dispersed with ct-Fe phase with an average grain size of 15-35 nm were obtained by appropriately annealing the melt-spun ribbons at 683 K for 5 min. The Fe83.25P10C6Cu0.75 nanocrystalline alloy ex- hibits a high Bs of 1.65 T, low Hc of 3.3 A/m and high μc at 1 kHz of 21 100, which is superior to the traditional FePC soft magnetic alloys. The core loss is as low as 0.32 W/kg at 1.0 T and 50 Hz, which is 60% that of nonoriented Fe 6.5 mass% Si-steel. It is encouraging to synthesize this Fe-based nanocrystalline alloy with excellent soft-magnetic properties even using commercially industry-grade raw materials, which is promising for the future industrial applications.展开更多
基金This work was supported by the National Basic Research Program of China (Nos. 2011CB932401, 2011CBA00500, and 2012CB224802), and the National Natural Science Foundation of China (Nos. 21221062, 21171105, 21322107 and 21131004).
文摘Porous Pt-Fe bimetallic nanocrystals have been synthesized via self-assembly and can effectively facilitate the synthesis of 2-propanol from acetone. The bimetallic catalyst has three--dimensional channels and shows turnover frequencies (TOFs) of up to 972 h^-1 for a continuous process more than 50 h. Preliminary mechanistic studies suggest that the high reactivity is related to the interface consisting of a bimetallic Pt-Fe alloy and Fe2O3-x. An understanding of real catalytic behavior and the catalytic mechanism based on model systems has been shown to help fabricate an improved Pt/Fe3O4 catalyst with increased activity and lifetime which has great potential for large-scale industrial applications.
基金supported by the National Basic Research Program of China(2015CB856600)the National Natural Science Foundation of China(21422209,21432011,21421091)
文摘Olefins find widespread applications in the synthesis of polyolefins and fine chemicals. With an increasing demand for olefins, the technologies for alkane dehydrogenation have drawn much attention. Several types of heterogeneous catalysts have found applications in industry for the dehydrogenation of light alkanes, mainly ethane, propane, and butane. In the past three decades, a number of transition-metal complexes,particularly pincer-ligated iridium complexes, have been developed as the homogeneous catalysts for alkane dehydrogenations. The homogeneous catalyst systems operate under much milder conditions compared with the heterogeneous systems, and some systems exhibit good activity and high regioselectivity in dehydrogenation of alkanes longer than butane.
基金supported by the National High Technology Research and Development Program of China ("863" Program) (Grant No.2009AA03Z214)the National Science Fund of China for Distinguished Young Scholars (Grant No. 50825103)+1 种基金the National Natural Science Foundation of China (Grant No. 51001112)the "Hundred of Talents Program" (Grant No. KGCX-2-YW-803) by Chinese Academy of Sciences
文摘The effect of Cu addition on crystallization behavior and soft magnetic properties of Fe84-xP10C6Cux (x = 0-1.15) alloys was investigated. Low-cost FePCCu nanocrystalline alloys dispersed with ct-Fe phase with an average grain size of 15-35 nm were obtained by appropriately annealing the melt-spun ribbons at 683 K for 5 min. The Fe83.25P10C6Cu0.75 nanocrystalline alloy ex- hibits a high Bs of 1.65 T, low Hc of 3.3 A/m and high μc at 1 kHz of 21 100, which is superior to the traditional FePC soft magnetic alloys. The core loss is as low as 0.32 W/kg at 1.0 T and 50 Hz, which is 60% that of nonoriented Fe 6.5 mass% Si-steel. It is encouraging to synthesize this Fe-based nanocrystalline alloy with excellent soft-magnetic properties even using commercially industry-grade raw materials, which is promising for the future industrial applications.