期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
P204-HCl-HAc体系萃取La的机理分析与萃取平衡常数 被引量:2
1
作者 李剑虹 张兴 《稀有金属与硬质合金》 CAS CSCD 北大核心 2010年第2期11-13,25,共4页
在pH>1条件下,采用EDTA容量滴定法测定P204-HCl-HAc体系萃取La(Ⅲ)过程两相中的La浓度,并分别考察溶液酸度和萃取剂浓度对La分配比的影响;通过对P204以及P204-HCl-HAc体系负载La有机相进行红外光谱测试分析,探究P204-HCl-HAc体系萃... 在pH>1条件下,采用EDTA容量滴定法测定P204-HCl-HAc体系萃取La(Ⅲ)过程两相中的La浓度,并分别考察溶液酸度和萃取剂浓度对La分配比的影响;通过对P204以及P204-HCl-HAc体系负载La有机相进行红外光谱测试分析,探究P204-HCl-HAc体系萃取La的机理,并确定其萃取平衡常数。研究结果表明,当pH>1时,萃取过程实质是La离子与基团P-OH遵循阳离子交换机制发生置换,以及与基团P=O发生络合配位作用,其萃取平衡常数KLa为10-0.02。 展开更多
关键词 P204-HCl-HAc la红外光谱 萃取机理 萃取平衡常数
下载PDF
Fabrication of LaNiO3 nanofibers by electrospinning
2
作者 WANG Jin-xian DONG Xiang-ting QU Zhen LIU Gui-xia 《Journal of Chemistry and Chemical Engineering》 2009年第8期25-31,共7页
In order to acquire LaNiO3 nanofibers with particular morphology and structure, electrospinning technique, for the first time, was successfully applied to fabricate LaNiO3 nanofibers in the paper. Polyvinyl alcohol(... In order to acquire LaNiO3 nanofibers with particular morphology and structure, electrospinning technique, for the first time, was successfully applied to fabricate LaNiO3 nanofibers in the paper. Polyvinyl alcohol(PVA)/ [La(NO3)3+Ni(CH3COO)2] composite nanofibers were fabricated by electrospinning, and polycrystalline LaNiO3 nanofibers were prepared by calcination of the PVA/[La(NO3)3+Ni(CH3COO)2] composite nanofibers at 6000C for 10 h. The samples were characterized by using thermogravimetric-differential thermal analysis (TG-DTA), X-ray diffraction spectrometry(XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR). The results showed that PVA/[La(NO3)3+ Ni(CH3COO)2] composite nanofibers were amorphous in structure, and pure phase LaNiO3 nanofibers were trigonal with space group R3m. The surface of as-prepared composite nanofibers was smooth, and the diameter was about 200 nm. The diameter of LaNiO3 nanofibers was smaller than that of the relevant composite fibers. The surface of the LaNiO3 nanofibers becomes coarse with the increase of calcination temperatures. The diameter of LaNiO3 nanofibers was ca. 80 nm, and the length was greater than 100μm. The mass of the sample remained constant when the temperature was above 463℃, and the total mass loss percentage was 90.9%. Possible formation mechanism of LaNiO3 nanofibers was preliminarily proposed. 展开更多
关键词 laNIO3 laNTHANUM NICKEL nanofibers electrospinning
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部