多孔载体在合成气催化转化为高级醇方面起着重要作用,这有望提高C1化学的可持续性。在这项工作中,通过超声辅助浸渍成功地制备了由合成气合成高级醇的一系列分级空心二氧化硅球(HHSS)负载的Cu-Fe双金属催化剂。结构表征结果表明,可以保持HHSS载体的分层空心结构,并且Cu-Fe双金属纳米粒子高度分散在HHSS表面。研究了样品在CO加氢测试中催化高级醇合成的催化性能。结果表明,CO的转化率和C 2+的选择性随着Cu x Fe y @HHSS催化剂中Cu含量的减少,OH醇先增加然后减少。与Cu-Fe @ HHSS催化剂相比,最高的CO转化率,醇选择性和STY ROH分别为65.1%,46.6%和118.1 gkg -1 h -1。发现在Cu-Fe @ HHSS催化剂中形成了大量的CuFe 2 O 4,并且还证实了CuFe 2 O 4尖晶石和CuO-CuFe 2 O 4转化为Cu-Fe 5 C 2。废Cu-Fe
At the frontier between heterogeneous and homogeneous catalysis: hydrogenation of olefins and alkynes with soluble iron nanoparticles
作者:Claudine Rangheard、César de Julián Fernández、Pim-Huat Phua、Johan Hoorn、Laurent Lefort、Johannes G. de Vries
DOI:10.1039/c0dt00177e
日期:——
nanoparticles in the hydrogenation of unsaturated C–C bonds is a green catalytic concept at the frontier between homogeneous and heterogeneous catalysis. Iron nanoparticles can be obtained by reducing Fe salts with strong reductants in various solvents. FeCl3 reduced by 3 equivalents of EtMgCl forms an active catalyst for the hydrogenation of a range of olefins and alkynes. Olefinhydrogenation is relatively
Effect of grain size on the electrical conductivity of copper–iron alloys
作者:Sardar Farhat Abbas、Seok-Jun Seo、Kyoung-Tae Park、Bum-Sung Kim、Taek-Soo Kim
DOI:10.1016/j.jallcom.2017.05.244
日期:2017.10
Abstract Copper–ironalloys (CFAs) are a much anticipated class of materials for electrical contacts, magnetic recordings, and sensors. In this study, Cu100-xFex alloys (x = 10, 30, or 50, representative of the Fe content in at%) were prepared via gas atomization, followed by sintering and heat treatment in vacuum. The electrical conductivity of the alloys was determined as a function of the grain
dehydrogenation of hydroushydrazine (N2H4·H2O). The excellent catalyticperformance of the Cu0.4Ni0.6Mo catalyst may be attributed to the electronic modification among Cu, Ni and Mo, and may also be related to the strong basic sites of Cu0.4Ni0.6Mo. The present simple, low cost, highly efficient, and highly selective catalyst may promote the practical application of N2H4BH3 as an effective hydrogenstorage material
肼硼烷(N 2 H 4 BH 3,H 15.4 wt%H)由于其固有的优势(例如高氢含量和高固态稳定性)而被认为是一种很有前途的储氢材料。然而,由于需要昂贵的贵金属基催化剂,强烈抑制了N 2 H 4 BH 3在产生氢中的实际应用。为了克服这一挑战,在室温和环境气氛下使用简便的化学还原方法制备了不含贵金属的CuNiMo纳米催化剂。出乎意料的是,所得的CuNiMo催化剂表现出优异的催化活性和100%的H 2。N 2 H 4 BH 3通过其BH 3基团水解和N 2 H 4部分在323 K分解生成氢的选择性。据我们所知,这是第一个关于无贵金属催化剂实现氢键反应的报道。 N 2 H 4 BH 3完全转化为H 2。另外,CuNiMo可以实现含水肼(N 2 H 4 ·H 2 O)的完全脱氢。Cu 0.4 Ni 0.6的优异催化性能Mo催化剂可能归因于Cu,Ni和Mo之间的电子修饰,也可能与Cu 0.4 Ni
Near room temperature magnetocaloric properties and critical behavior of binary Fe Cu100−Nanoparticles
rare earth-free magnetocaloric materials are being intensively studied for near room temperature, energy efficient, “green”, magnetic cooling applications. We report the magnetocaloric properties and critical analysis of ball milled Fe x Cu 100- x nanoparticles for x = 30 to 35. Magnetization measurements of Fe x Cu 100- x nanoparticles show soft ferromagnetic behavior at room temperature with small coercivity
摘要 低成本、不含稀土的磁热材料正在被深入研究,用于接近室温、节能、“绿色”的磁冷却应用。我们报告了球磨的 Fe x Cu 100- x 纳米粒子的磁热特性和临界分析,x = 30 到 35。Fe x Cu 100- x 纳米粒子的磁化测量显示室温下软铁磁行为,矫顽力 (HC) 值很小。居里温度 (TC) 可以在很宽的温度范围内进行调整,从 268 K 到 360 K,具有不同的 Fe 含量。阿罗特图的正斜率证实了磁跃迁的二阶性质。使用修改后的 Arrott 图对磁相变的关键分析支持 3D-Heisenberg 模型。磁热效应 (MCE) 即,Fe x Cu 100- x 纳米颗粒的等温磁熵 (Δ S m ) 和相对冷却功率 (RCP) 的变化与其他铁基合金的变化相当。Fe x Cu 100- x 纳米颗粒的高导热性、软铁磁行为和磁热性能对于低成本、无稀土元素的磁冷却应用具有潜在的有用性。
Amorphous structure of the immiscible Fe<sub>1-y</sub>(Cu<sub>1-x</sub>Ag<sub>x</sub>)<sub>y</sub>alloy system
作者:K Sumiyama、K Nishi、K Suzuki
DOI:10.1088/0953-8984/3/49/003
日期:1991.12.9
Fe1-y(Cu1-xAgx)y alloys sputter deposited on liquid-nitrogen-cooled substrates have been investigated by X-ray diffraction and differential scanning calorimetry measurements. Although this ternary alloy system is of a typically immiscible type in the equilibrium state, a single BCC phase appears at the Fe-rich corner and a single FCC phase at the Cu- and Ag-rich corners, while an amorphous phase appears
Fe1-y (Cu1-xAgx) y 合金溅射沉积在液氮冷却基板上已通过 X 射线衍射和差示扫描量热法测量进行了研究。虽然这种三元合金系统在平衡状态下是典型的不混溶类型,但在富铁角出现单个 BCC 相,在富铜和富银角出现单个 FCC 相,而在中心出现非晶相集中区。在三元非晶合金的干涉函数中,检测到较宽的第一峰和第二和第三峰的分裂,其中峰强度比二元FCC合金弱得多。径向分布函数表明四面体是非晶合金的主要结构单元,正如从硬球或土球的密集随机堆积所预期的那样。