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51.
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Based on the investigation of a non-ionic surfactant-salt-H2O liquid-liquid extraction system, general rules concerning salt selection are concluded and the mechanism of phase separation is explained. The extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydrochloride (PCN) in such a system is studied. Research shows that the extraction efficiency of CPZ can amount to 96% by twice extraction, which means that quantitative extraction is realized, while that of PCN is 77%. This system produces distribution coefficients (KD) of 12.3 and 2.6, respectively, for CPZ and PCN. Extraction mechanism is deduced according to ultraviolet absorbance; and molecular fluorescence spectra change of the drugs in the system studied. 相似文献
53.
手性配体立体选择性萃取分离扁桃酸对映体 总被引:6,自引:0,他引:6
Based on chiral ligand exchange, the distribution behavior of mandelic acid enantiomers in the two-phase system containing copper ion(Ⅱ)(Cu2+) and N-n-dedecane-L-hydroxyproline (L), was studied. At different pH, the partition of Cu2+ in the two-phase system containing N-n-dedecane-L-hydroxyproline, was investigated. The formation constant of binary cpmplex(Li2Cu) was obtained by regression. The influence of pH, concentrations of Cu2+ and chiral ligand, and solvents on partition coefficients(K) and separation factor(α), was discussed. The experimental results show that Li forms more stable ternary complex with D-mandelic acid than with L- mandelic acid. There is a large influence of pH on K and α. At low pH values (<3.5), formation of binary complexes is thermodynamically unfavourable. K and α are best when pH values are above 3.5 and the molar ratio of chiral ligand to Cu2+ is 2∶1. At the same time, solvents influence K and α very much. 相似文献
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采用对掺入La_2O_3的石墨棒原位活化并结合交换电极回放方法制备了产率较高的金属富勒烯,并用甲苯高温热提取的方法有效地提取出La@C_(2n),其中La@C_(74)为可溶性金属富勒烯增加了新成员.同时,首次采用解吸电子轰击质谱对提取物进行了表征,讨论了提取物的ESR谱. 相似文献
56.
Simultaneous isolation and determination of esculin and rutin in natural materials using SPE and HPLC 总被引:1,自引:0,他引:1
Summary Esculin (ESC) and rutin (RUT) have been simultaneously isolated from pharmaceutical natural materials by solid phase extraction (SPE). Determination of both substances was performed by reversed phase high performance liquid chromatography (RPHPLC) with UV detection. Optimization of the separation conditions showed that simultaneous isolation and determination of rutin and esculin from pharmaceutical material was possible. The recovery obtained was not lower than 95±2%. 相似文献
57.
Gas-stirred propylene carbonate (PC) extraction can be performed by bubbling nitrogen without loss of volume. This extraction technique has proved to be highly useful for the separation and subsequent direct polarographic estimation of Tl(III) in the recovered PC phase. Tl(III) can be determined by differential-pulse polarography over the concentration range of 0.4 10 g ml–1 without any interferences due to most metal ions such as Pb(II), Bi(III), Cu(II), Sb(III) and As(III). This proposed technique would be possible to use as a simple extraction step prior to the final estimation by instrumental method of analysis such as atomic absorption spectrometry or spectrophtometry. 相似文献
58.
Fiber-in-Tube Solid Phase Extraction (FIT-SPE) for Miniaturized Sample Preparation Process 总被引:2,自引:0,他引:2
A typical analytical separation procedure has several important steps: sample preparation, isolation, identification, quantitation, statistical evaluation and final decision. Each step is alwayscritical to obtain correct results to fulfill the analytical purpose. In these various steps sample 相似文献
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