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随着纳米材料制备技术和性能研究的发展,一维纳米材料日益受到人们的关注.简要介绍了一维氧化镓纳米材料的制备方法及其光致发光机理,并指出了当前研究过程中存在的问题和可能的发展方向. 相似文献
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核级锆铪的制备是核工业安全快速发展的重要保障,锆铪深度分离是关键。锆铪分离的方法分为火法和湿法两大类。工业上获得核级锆铪的主要方法是溶剂萃取,萃取分离体系主要有甲基异丁酮(MIBK)-硫氰化氢(HSCN)、磷酸三丁酯(TBP)-硝酸(HNO3)和三辛基胺(TOA)-硫酸(H2SO4),但都存在萃取效率低、萃取剂用量大、环境污染严重等不足。学者们一直致力于开发绿色高效的锆铪分离型新萃取体系,如胺类萃取剂、中性膦类萃取剂、有机膦/磷酸类萃取剂、羟肟酸类萃取剂、协同萃取体系等。以优先萃取锆/铪为切入点,从优先萃锆体系和优先萃铪体系两个方面阐述不同萃取体系萃取分离锆铪的机理、性能及优缺点,为锆铪萃取分离提供新思路。 相似文献
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刘艳红 《中国新技术新产品》2012,(14):7
生物碱是一类具有显著生物活性的含氮有机化合物,是许多药用植物的有效成分。利用现代技术对天然产物中的生物碱进行提取分离,对于开发其药用价值,阐明药效物质基础具有重要意义。因此生物碱的提取分离方法备受人们关注,本文对近年来生物碱提取分离方法进行综述。 相似文献
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静电式准液膜从稀土溶液中提取浓缩与分离钪的研究 总被引:4,自引:0,他引:4
静电式准液膜是本实验室发展起来的一种新型的化工分离技术,本文报道了以噻吩甲酰三氟丙酮(TTA)或1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5(PMBP)为载体的静电式准液膜分离提取钪的机理及其传质过程,研究了静电式准液膜分离提取钪的工艺条件诸如萃取剂及其浓度、电场强度、孔板材料、料液pH值、浓度以及流量对提取效率的影响,提出了测量静电式准液膜分离过程中泄漏率和“溶胀”率的简易计算式,进行了模拟稀 相似文献
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离子液体在萃取分离中的应用进展 总被引:1,自引:0,他引:1
作为环境友好型功能材料——离子液体以其独特的物理化学性质已引起人们的广泛关注。离子液体在萃取分离有机物、无机金属离子领域的应用越来越多。概述了离子液体在萃取分离中的应用。总结了离子液体的萃取机理,介绍了离子液体的结构如阴、阳离子的类型对萃取效率的影响规律,讨论了静电作用、疏水作用、氢键等作用力在萃取分离过程中所扮演的角色。最后展望了离子液体在萃取分离领域的发展方向。 相似文献
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《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(5):353-365
A new fullerene derivatives poly(β-styryl)-(12-methanofullerene-C60)-61-formo hydroxamic acid has been synthesized and applied for the solid phase extraction, separation, preconcentration and ICP-MS determination of Ce, La, Pr, Nd, Sm and Gd. The introduction of the fullerene moiety into poly(β-styryl)-hydroxamic acid enhances its reactivity, chemical stability and recycled for their determination. The various parameter, viz. kinetics of sorption, breakthrough studies, effect of eluents, etc., have been studied. The influence of several diverse ions is also discussed. The proposed method has been applied for the sequential chromatographic separation of rare earths in the presence of each from rocks, monazite sand and in environmental samples. 相似文献
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通过金属有机物化学气相沉积方法在碳纳米管模板上生长氮化镓纳米线束.对所生长的纳米结构进行了扫描电镜和X射线能谱分析,结果显示氮化镓纳米晶体可以与碳纳米管形成纳米线束状复合物.纳米线束状复合物直径为100~200 nm,长度为1.5~2.5μm,纳米线的两端呈现尖角状.由于氨气很容易吸附在碳纳米管表面,可知所获得的纳米结构的初始生长机制为碳纳米管的表面氮化.该研究也证明金属有机物化学气相沉积将是用于制造化合物纳米结构材料的一项有效的技术. 相似文献
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Many solid wastes contain both zinc and nickel at the same time. For recycling or recovery of metals, it is essential to separate materials. Among those materials, zinc and nickel are very difficult to be separated because there is not so much difference in the chemical and physical properties. This paper focuses on the separation of zinc and nickel ions in a diluted aqua regia solution. Liquid-liquid extraction by TBP, Cyanex 272 and Cyanex 301 was used and a distribution coefficient (D), a separation factor (S) and a relative purity (R) were induced to evaluate the degree of separation. All of the extractions were proportional to the concentration of the extractants, and zinc ions were extracted more easily than nickel ions. Among the extractants, Cyanex 301 showed the best characteristics regarding Zn/Ni separation. In particular, the extraction of zinc ions in the range of pH相似文献
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Tetsuya Kambe Aiko Watanabe Meijia Li Takamasa Tsukamoto Takane Imaoka Kimihisa Yamamoto 《Advanced materials (Deerfield Beach, Fla.)》2020,32(14):1907167
Superatoms have been investigated due to their possible substitution for other elements. The solution-phase synthesis of superatoms has attracted attention to realize the availability of superatoms. However, the previous approach is basically limited to the formation of a single cluster. Here, superatoms are investigated and the number of valence electrons in these superatoms is changed by designing the number of gallium atoms present. Based on the dendrimer template method, clusters consisting of 3, 12, 13, and other numbers of atoms have been synthesized. The halogen-like superatomic nature of Ga13 is structurally and electrochemically observed as completely different to the other clusters. The gallium clusters of 13 and 3 atoms, which can fill the 2P and 1P superatomic orbitals, respectively, exhibit different reactivities. The 3-atom gallium cluster is suggested as being reduced to Ga3H2− due to the lower shift of energy levels in the unoccupied orbitals. The results for these gallium clusters provide candidates for superatoms. 相似文献
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电沉积NiHCF薄膜在碱土金属溶液中的电控离子分离性能 总被引:4,自引:0,他引:4
采用电沉积方法在铂基体上制备出电活性NiHCF(Nickel Hexacyanoferrate)薄膜,在碱土金属溶液中考察了薄膜电极对碱土金属离子的电控离子分离性能.通过循环伏安法在0.1mol·L-1Mg(NO3)2、Ca(NO3)2、Sr(NO3)2和Ba(NO3)2溶液中可逆置入和释放碱土金属离子,比较了不同溶液中NiHCF膜电极的电活性、电化学行为和离子的置入机制;在0.1mol·L-1[Mg(NO3)z Ba(NO3)2]混合溶液中结合电化学石英晶体微天平(EQCM)原位检测了不同浓度下膜电极氧化还原过程中的伏安特性曲线和频率响应,分析了薄膜对Mg/Ba离子的选择性;并通过XPS测定了氧化还原状态下NiHCF膜的化学组成及元素价态.结果表明,NiHCF膜在二价碱土金属溶液中具有可逆的离子交换行为,对Ba2 离子的选择性大于Mg2 离子,通过电控离子分离方法可以实现碱土金属离子的有效分离. 相似文献