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1.
空气—乙炔焰中钇对镱的增感效应及其分析应用   总被引:2,自引:0,他引:2  
研究了在盐酸介质中钕,钇,镧,铕,以及高氯酸介质中钇对空气-乙炔火焰原子吸收光谱法测定镱的增感效应,建立了钇作增感剂和干扰抑制剂,直接测定富钇混合稀土浓集物与氧化钇粗产品中镱的新方法。  相似文献   

2.
可变误差多面体法测定多组份稀土元素   总被引:3,自引:0,他引:3  
在实验三种显色体系的基础上,确定以DBC-偶氮氯膦为显色剂,在盐酸-草酸介质中,对15个稀土元素进行吸收光谱测定。按吸收光谱的差异,将15个稀土元素分为镧、钇、钕、钆、镝、镱六组。用可变误差多面体的计算方法,考察计算参数及约束条件对计算结果的影响,其中以浓度上限的影响较大。为此,提出“浓度上限选代法”,以期克服其影响。该法用于同时测定铝-稀土合金样品中镧、钇、钕、钆、镝、镱6个稀土组的含量,结果与与荧光光谱分析法基本相符。  相似文献   

3.
研究用ICP-AES法测定高温质子导体中的钡、铈、锶、钇和镱,选定了适宜的溶解方法及分析条件,在溶解酸中加入盐酸羟胺,获得了较为满意的分析结果,相对标准差小于10%。  相似文献   

4.
设计了在线液-液萃取多用重分布相器及相应流动注射流路系统与ICP-AES法联用。具有良好的分析性能,通过对矿石中某些重稀土元素在硝酸介质中被TBP萃取的应用研究表明钇,镱,铒的检出限(3σ)分别为6.8ng/mL,0.2ng/mL和1.5ng/mL,精密度(RSD%)分别为0.24,0.47和1.8,进样频率为25-30个/h。  相似文献   

5.
设计了在线液-液萃取多用重力分相器及相应流动注射流路系统与ICP-AES法联用,具有良好的分析性能.通过对矿石中某些重稀土元素在硝酸介质中被TBP萃取的应用研究表明钇、镱、铒的检出限(3σ)分别为:6.8ng/mL、0.2ng/mL和1.5ng/mL.精密度(RSD%)分别为0.24、0.47和1.8.进样频率为25~30个/h.  相似文献   

6.
钱长涛  王兵 《化学学报》1996,54(11):1084-1088
双(2-甲氧乙基环戊二烯基)氯化镧或氯化镱, 在四氢呋喃中, -20℃下,分别与苯乙炔基钠发生交换反应, 生成双(2-甲氧乙基环戊二烯基)苯乙炔基镧或镱, 产率分别为77%和66%。直接将无水三氯化镱或三氯化钇, 在四氢呋喃中, 冰水冷却下, 与两摩尔的双(三甲基甲硅烷基)氨基锂和2-甲氧乙基环戊二烯基钠进行一锅煮反应, 可得2-甲氧乙基环戊二烯基双(双三甲基甲硅烷基氨基)镱或钇, 产率分别为56%和72%。配合物经元素分析, 红外光谱, 核磁共振氢谱和质谱的鉴定, 它们可能是非溶剂化的, 含分子内配位键的中性单体配合物。  相似文献   

7.
本文介绍应用ICP发射光谱法,同时测定岩石中镧、铈、镨,钕、钐、钇、镱、钍八种稀土元素,研究了元素间的相互干扰及其消除办法。分析结果可满足岩石中稀土总最在100—200μg/g范围内定量分析要求。  相似文献   

8.
双(2-甲氧乙基环戊二烯基)氯化镧或氯化镱,在四氢呋喃中,20℃下,分别与苯乙炔基钠发生交换反应,生成双(2-甲氧乙基环戊二烯基)苯乙炔基镧或镱.产率分别为77%和66%直接将无水三氯化镜或三氯化钇,在四氢呋喃中,冰水冷却下,与两摩尔的双(三甲基甲硅烷基)氨基锂和2-甲氧乙基环戊二烯基钠进行一锅煮反应,可得2-甲氧乙基环戊二烯基双(双三甲基甲硅烷基氨基)镱或钇,产率分别为56%和72%.配合物经元素分析,红外光谱,核磁共振氢谱和质谱的鉴定,它们可能是非溶剂化的,含分子内配位键的中性单体配合物.  相似文献   

9.
3-(4-氯苯偶氮)-6-(4-氯-2-瞵酸基苯偶氮)-4.5-二羟基-2.7-萘二磺酸,简称对氯偶氮氯膦(CPA-PCl),是近年新合成的一种不对称变色酸双偶氮衍生物:利用该试剂光度特性测定钪、钇、铋、镱已有报道,本文研究了该试剂与铝显色反应的条件及配合物的吸光光度性质。发现在微酸性介质中,试剂与铝可以形成2:1的蓝色配合物,显色迅速,色泽稳定,配合  相似文献   

10.
在中性及微碱性溶液中,稀土与(口底)唑(STA)、溴化十六烷基三甲铵(CTMAB)形成红色三元络合物,其最大吸收峰位于570nm(仅铈为580nm),摩尔吸光系数为6.1-8.4×10~4。三元络合物中Ce:STA=1:3,La(Y,Yb):STA=1:2.鉴于在pH6.8并加大CTMAB的用量(使〔CTMAB〕/〔RE〕>600)时,镧、镨、钕的三元络合物受到抑制。而铈及重稀土络合物的吸光度降低甚少,提出了不需将铈氧化的直接测定镧中千分之几含量铈及轻稀土混合物中铈的简便分析方法,也可用于镧-镱、钕-钇二元混合物中镱和钇的测定。  相似文献   

11.
利用HZOZ和苹酚联产对苯二醋和邻苯二酚是目前二酚生产领域中比较活跃的课题.长久以来,人们曾利用酸、金属盐、金属配合物等作为催化剂,在均相体系中来研究其对苯酸羟化反应的催化活性.由平均相反应存在着明显的缺点,后来又转向了多相催化剂的开发,先后出现了TSull]TS42  相似文献   

12.
In this study, a pH-sensitive drug release system was prepared by zeolite Y nanoparticles and tannic acid. Zeolite Y nanoparticles were synthesized via hydrothermal synthesis of colloidal suspensions and after that, were coated with tannic acid. In order to evaluate its performance, metronidazole as an anti-protozoan drug was loaded into nanocarriers via immersing method to study the in-vitro drug delivery behavior. This nanocomposite carriers represented pH-sensitive behavior and had more and faster release in acidic medium. In-vitro effects of metronidazole-loaded nanoparticles was measured against Trichomonas gallinae trophozoites in Trypticase Yeast extract Maltose medium. The results suggested that metronidazole-loaded and tannic acid-modified zeolite Y nanoparticles could be a potential anti-trichomonal agent.  相似文献   

13.
Liu Y  Sun X  Luo F  Chen J 《Analytica chimica acta》2007,604(2):107-113
A new material (IL923SGs) composed of ionic liquids and trialkyl phosphine oxides (Cyanex 923) for Y(III) uptake was prepared via a sol-gel method. The hydrophobic ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate (C8mim+PF6) was used as solvent medium and pore templating material. The extraction of Y(III) by IL923SGs was mainly due to the complexation of metal ions with Cyanex 923 doped in the solid silica. Ionic liquid was stably doped into the silica gel matrix providing a diffusion medium for Cyanex 923, and this will result in higher removal efficiencies and excellent stability for metal ions separation. IL923SGs were also easily regenerated and reused in the subsequent removal of Y(III) in four cycles.  相似文献   

14.
Although Brust-Schiffrin two-phase synthesis is a popular method for synthesizing ligand-protected metal nanoparticles with an average size of less than 5 nm, the details on how the reactions can be controlled from a mechanistic point of view are still unclear, therefore hindering efforts to synthesize monodisperse metal nanoparticles. It was recently discovered that this method is basically an inverse-micelle-based synthesis (Li, Y.; Zaluzhna, O.; Xu, B.; Gao, Y.; Modest, J. M.; Tong, Y. Y. J. J. Am. Chem. Soc.2011, 133, 2092). In this letter, the critical role of water and the structure of inverse micelles in typical synthesis of gold nanoparticles were further investigated. We found that (1) water encapsulated in the inverse micelles of [TOA](+) that also hosted metal ions formed a hydrophilic microenvironment that acted as a reaction-enabling proton-accepting medium for the thiol protons (RS-H) and (2) not only the presence but also the amount of water in the reaction medium has a profound effect on the Au(I) precursor species (a pure [TOA][AuX(2)] complex or a mixture of a [TOA][AuX(2)] complex and polymeric [Au(I)SR](n) species), the reduction of Au(III) by thiols, and the formation of uniform small metal nanoparticles. A quantitative analysis of the (1)H NMR of the encapsulated water enabled an estimation of the size and composition of the involved inverse micelles.  相似文献   

15.
Perchloric acid was found to be a suitable medium for the quantitative leaching of Sr(II) from homogeneous and calcined (Th,Sr)O2 particularly with respect to the contamination from Th(IV). 90Sr is a cause of major concern to the environment due to its long half life (28.6 years), significant abundance in large inventory of spent nuclear fuels (~350 thousand tons) awaiting geological disposal and its chemical similarity to Ca(II), an essential element for the living beings. Application of 90Sr as a parent radionuclide for 90Y (used in therapy radiopharmaceuticals) is possible provided it can be made available at desired high purity. In this context, the distribution coefficients of Sr(II), Th(IV), Zr(IV), Y(III), 152Eu(III) and 137Cs(I) were determined using Sr selective crown ether 4,4′(5′)-di-tert-butyl-dicyclohexano-18-crown-6 by solid–liquid extraction in perchloric acid medium. Feasibility of employing extraction chromatography using Sr selective resin for the recovery and purification of Sr(II) from leached perchloric acid medium was explored. Perchloric acid medium is better than nitric acid medium for the uptake of Sr by Sr selective chromatographic resin under varying loading conditions of Sr(II). Similarly pH 2 solution appears better eluent of Sr(II) than distilled water. Present work offers a novel approach for setting up a 90Sr–90Y generator.  相似文献   

16.
采用柠檬酸表面修饰 Y2 O3:Eu3 颗粒 ,苯乙烯乳液聚合的方法 ,制备出核 -壳型的 Y2 O3:Eu3 /聚苯乙烯颗粒 .在 FTIR谱图上 ,羰基伸缩振动峰向低波数位移 ;在 XPS谱图上 ,Y3d5 / 2 的电子结合能向高能方向移动 ,表明柠檬酸和颗粒表面发生键合作用 .说明此过程符合吸附层媒介作用机理 :柠檬酸使颗粒表面变成两亲性 ,从而使苯乙烯可吸附在颗粒表面形成包覆无机核的乳液结构 .EDS谱图表明聚苯乙烯均匀地包覆在颗粒表面  相似文献   

17.
采用X射线粉末衍射(XRD)、魔角旋转固体核磁共振(MAS NMR)、程序升温脱附(TPD)以及吡啶-傅里叶变换红外(Py-FTIR)光谱等方法研究了稀土离子对Y型分子筛结构稳定性和酸性的影响.结果表明:稀土离子的引入不仅显著增强了Y型分子筛的结构稳定性,而且调变了分子筛酸性,使分子筛中等强度酸中心数量增多,强酸中心数量减少.结合密度泛函理论(DFT)计算结果,从理论上阐述了这种机制:进入分子筛β笼l′位的稀土离子与骨架O原子相互作用,增加了Al-O作用力,提高了分子筛的结构稳定性,从而避免了骨架Al的脱除和非骨架Al物种的生成,进而导致稀土氧Y(REHY)分子筛的Br(o)nsted (B)酸强度较USY分子筛的弱;但与HY分子筛相比,稀土离子的引入使骨架O1负电荷减弱,Al-O1键长变短,O1-H作用力减弱,导致REHY分子筛的B酸强度较HY分子筛的强;在酸中心数量方面,REHY分子筛的B酸中心数量比USY分子筛的多,但比HY分子筛的少.  相似文献   

18.
亚氨基二乙酸树脂吸附钇(Ⅲ)的研究   总被引:14,自引:0,他引:14       下载免费PDF全文
熊春华  吴香梅 《无机化学学报》2003,19(12):1356-1360
The adsorption behavior and mechanism of a novel chelate resin, iminodiacetic acid resin (IDAAR) for Y(Ⅲ) were investigated. The statically saturated adsorption capacity is 102mg·g-1 resin at 298K in HAc-NaAc medium at pH 5.7. Y(Ⅲ) adsorbed on IDAAR can be reductively eluted by 1.0~4.0mol·L-1 HCl used as eluant and the elution percentages are almost as high as 100%. The resin can be regenerated and reused without apparent decrease in adsorption capacity. The apparent adsorption rate constant is k298=3.36×10-5s-1. The adsorption behavior of IDAAR for Y(Ⅲ) conforms to Freundlich′s model reasonably. The thermodynamic adsorption parameter, enthalpy change ΔH of IDAAR for Y(Ⅲ) is 18.6kJ·mol-1. The complex molar ratio of the functional group of IDAAR to Y(Ⅲ) is about 3∶1. The adsorption mechanism of IDAAR for Y(Ⅲ) was examined by using chemical method and IR spectrometry.  相似文献   

19.
The effect of solvents, halo substituents and surfactants on the aggregation of xanthene dyes (fluorescein and eosin Y) has been investigated. It has been found that polar protic solvents promote the aggregation of both the dyes while polar aprotic solvents hinder the aggregation process. Apolar solvents can disintegrate the aggregates previously formed in aqueous medium. The nature of the driving forces for aggregation in the two dyes is different. Surfactants bearing charge opposite to the dye molecules facilitate aggregation. These observations bear direct relevance to the possible use of fluorescein and eosin Y as quantum yield standards, photosensitizers, laser dyes and biological labels.  相似文献   

20.
A relatively simple and rapid radioanalytical method, limited to milk, is adapted for investigating soil, biological and water samples for90Sr. The method is based on a selective separation and successive counting of equilibrium quantities of its daughter 90Y, which can be extracted by tributyl phosphate from nitrate medium and stripped by conc. ammonia solution. 90Y is separated from possible iron and measured by Cerenkov counting. The procedure is thoroughly tested with certified reference materials and used lately for determining90Sr in some environmental samples in the Riyadh region. The results obtained are given and discussed.  相似文献   

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