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91.
92.
Fan J Yudasaka M Kasuya D Azami T Yuge R Imai H Kubo Y Iijima S 《The journal of physical chemistry. B》2005,109(21):10756-10759
We present in this report a new type of particles with micrometer-order sizes, which we called giant graphitic balls (GG balls). The GG balls are produced by CO2 laser ablation of graphite together with single-wall carbon nanohorns. They have graphitic structures whose layers tend to align parallel with the GG-ball surfaces, resulting in polygonal-like arrangements. Comparing the GG-ball structure with that of the previously reported polygonal graphite-particles, the growth mechanism of the GG ball is discussed briefly. 相似文献
93.
Masako Nakagawa Hiroyuki Sugumi Shinichi Kodato Tohru Hino 《Tetrahedron letters》1981,22(52):5323-5326
First total synthesis of ditryptophenaline is described and the absolute configuration was determined. 相似文献
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The reaction rates of SO3 with CH3OH in He were measured at total pressures of 0.7–1.6 torr in flow tubes. The concentration of SO3 was monitored by the SO2* fluorescence from excitation of SO3 at 147 nm. The reaction rate constant of SO3 + CH3OH in the gas phase is determined to be (1.17 ± 0.16) × 10?13 cm3 molec?1 s?1 at room temperature. 相似文献
97.
A new method for synthesizing 6,7-dihydro-12 H-indolo[2,3-a] pyridocolinium bromide in one step from 3-(2-bromoethyl)-indole and 2-halogenopyridine is described. This method was applied to the synthesis of flavopereirine, an alkaloid isolated from Geissospermum laeve or vellosii. The mechanism of this reaction is discussed. 相似文献
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Capillary electrophoresis has been applied the analyses of many clinical drugs due to its rapid, high-resolution separation. In this study, electrokinetic chromatography involving the combination of SDS and dextran sulfate, which are synthetic polymers, was examined in order to obtain high resolution. Use of 2% dextran sulfate (10,000 molecular weight), 20 mm SDS running buffer containing boric acid solution (pH 9.2) and a silica capillary (inner diameter of 75 micro m, effective length of 50 cm, 57 cm overall length) afforded separation of 10 kinds of benzodiazepines. The detection limit was 0.2 micro g/mL; additionally, reproducibilities were de fi ned as the peak height and migration time. The average peak height was 5.92% (2.46-17.61), whereas the average migration time was 0.44% (0.18-0.76; n = 5). This separations system can be applied to the analysis and measurement of other pharmaceuticals as well. 相似文献