排序方式: 共有20条查询结果,搜索用时 31 毫秒
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溶剂化金属原子浸渍法制备Pd-Cu/γ-Al2O3低温CO氧化催化剂 总被引:5,自引:0,他引:5
Nano-particle Pd/γ-Al2O3 monometallic and Pd-Cu/γ-Al2O3 bimetallic catalysts were prepared by solvated metal atom impregnation (SMAI) method. The results of XRD measurement indicated that Pd- Cu alloy was formed in the bimetallic catalysts and the crystalline particle size of the alloy increased as Cu contents increased with av-erage diameters < 6.0nm for all the samples. XPS and Auger spectra showed that Pd was in zero- valent state, Cu existed mainly in zero- valent state and partially in monovalent state Cu+. The Pd/γ-Al2O3 and Pd-Cu/γ-Al2O3 catalysts exhibited higher activity for CO oxidation at low temperature. The activity of Pd-Cu/γ-Al2O3 bimetallic catalyst was higher than that of Pd/γ-Al2O3 monometallic catalyst. The Pd-Cu/γ-Al2O3 catalyst with Pd/Cu atomic ratio of 1∶1 showed the highest activity. 相似文献
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聚合物固载Co-Pd 催化剂的结构与活性 总被引:3,自引:0,他引:3
采用溶剂化金属原子浸渍(SMAI)法制备了几种不同金属含量的Co Pd催化剂,用X射线衍射、X射线光电子能谱和磁测定对催化剂进行表征,并与普通浸渍法(CI)制得的相同金属含量的催化剂进行比较.结果表明SMAI法制备的催化剂金属粒度小于CI法制备的催化剂,且前者零价金属含量高于后者.SMAI法制备的催化剂Co在表面上富集,而CI法制备的催化剂Co在表面和体相的金属含量基本相同.在二丙酮醇加氢及电催化反应中, SMAI法催化剂比相同组成的CI法催化剂具有更高的催化活性. 相似文献
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合成了一个新颖的含ONN席夫碱配体N-水杨醛基-2-氨乙基苯并咪唑(HL),并在甲醇体系中合成了它的配合物ICu(L)(bipy)]ClO4(bipy为2,2'-联吡啶).利用X-射线单晶衍射法测定了配合物的晶体结构.配合物[Cu(L)(bipy)lClO4的晶体属于单斜晶系,C2/c空间群,a=2.585 5(8)nm,b=1.4355(5)nm,c=1.6242(5)nm,β=124.434(5)°,Z=8.在配合[Cu(L)(bipy)lClO4中,每个铜离子的配位数为5,分别和配体L的1个氧原子和2个氮原子及2,2'-联吡啶的2个氮原子配位,形成畸变的三角双锥配位环境.配合物[Cu(L)(bipy)]ClO4巾的氧键和π-π相互作用将配合物[Cu(L)(bipy)]ClO4连接成二维网络结构.用红外光谱、紫外-可见光谱对配合[Cu(L)(bipy)]ClO4进行了表征,并用循环伏安法对配合物进行了电化学性质的研究. 相似文献
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Laboratory teaching not only enhances the students' interest for learning but also cultivates the scientific attitude of preciseness and ability for operation and innovation. It is the indispensable part for cultivation of top talented students. National Demonstration Center for Experimental Chemistry Education (Nankai University) attempted to cultivate the innovation sense and the ability to solve problems by construction of innovative laboratory teaching platform, organization of chemistry experiment competition and construction of high-level laboratory teaching team. 相似文献
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从软硬酸碱理论的起源出发,简要介绍软硬酸碱理论的建立背景、发展过程,并对其可能的应用范围做了讨论.最后结合人们对于软硬酸碱理论的认识和应用现状,做出总结和评价. 相似文献
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SMAI法制备的Co/SiO2催化剂及La3+促进Co/SiO2催化剂的比较 总被引:1,自引:0,他引:1
实验证明,钴基催化剂是非常有效的F-T合成催化剂. 由于钴基催化剂对形成长链烷烃具有高活性和高选择性,故它尤其适用于天然气间接转换为液态燃料和蜡的过程[1~5]. F-T合成用钴基催化剂由四个主要成分组成: 主金属(Co)、第二过渡金属、氧化物助剂(碱金属、稀土金属或过渡金属氧化物)及大比表面积氧化物载体(氧化硅或氧化铝)[5]. La对钴基催化剂的促进效果因其被加入到催化剂前体中的方式和顺序以及载体的性质和金属钴的状态等参数的变化而有所不同. 为了评价La对Co/SiO2催化CO加氢作用的促进效果,本文对溶剂化金属原子浸渍法(SMAI)制备的Co/SiO2和Co/La-SiO2进行了对比研究. 在保持某些参数(如载体的性质和金属钴的价态等)不变的情况下,评价了La的助催化效果,取得了一些有益的结果. 相似文献