The polymerization of acrylonitrile was first studied using (C9H7)2Y(μ-Et)2AlEt2 as a single-component catalyst. The catalytic activity could be greatly increased when PhONa was added to the catalyst in amount o...The polymerization of acrylonitrile was first studied using (C9H7)2Y(μ-Et)2AlEt2 as a single-component catalyst. The catalytic activity could be greatly increased when PhONa was added to the catalyst in amount of n(PhONa)/n(Cat)=3. A mechanism related to the polymerization initiation of AN is proposed.展开更多
文摘研究了以1-(2-吡啶偶氮)-2-萘酚(PAN)-吐温-80为显色体系,采用分光光度法测定钢样中的镍(Ⅱ)。在氨-氯化铵缓冲溶液体系中,镍(Ⅱ)与PAN形成红色稳定的络合物。其最大吸收波长为568 nm,表面摩尔吸光系数为ε568=4.62×104 L·mol-1·cm-1。镍(Ⅱ)含量在0~15μg/(25 m L)范围内服从比尔定律。采用联合掩蔽剂消除样品中的铁(Ⅲ)、铜(Ⅱ)、钒(Ⅴ)、铅(Ⅱ)、等对镍(Ⅱ)离子的干扰。使用该方法测定了38#、45#钢样中的镍(Ⅱ)含量,其RSD分别为2.60%、0.10%,加标平均回收率分别为101.48%、104.96%。此方法具有良好的准确性、选择性,且操作简便、快捷,结果满意。
文摘The polymerization of acrylonitrile was first studied using (C9H7)2Y(μ-Et)2AlEt2 as a single-component catalyst. The catalytic activity could be greatly increased when PhONa was added to the catalyst in amount of n(PhONa)/n(Cat)=3. A mechanism related to the polymerization initiation of AN is proposed.