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221.
Micellar electrokinetic chromatography (MEKC) and microemulsion electrokinetic chromatography (MEEKC) are two kinds of electrokinetic capillary chromatography (EKC), which are characterized of high solubilization capacity and separation efficiency. In our previous work, some polar organic compounds and hydrophobic neutral compounds were separated successfully by EKC1-3. In this paper, these methods were used for separating six pyridoncarboylxic acid derivatives with similar structures. T…  相似文献   
222.
Boehmeria siamensis Craib is distributed in China, Vietnam, Laos and Thailand1. The whole plants of B. siamensis were used in folk medicine2,3. Previous studies on the plants of this genus led to the isolation of different compounds such as alkaloids, flavones, lignans, triterpenoids and its glycosides4-9. Some antimicrobial alkaloids were obtained from B. cylindrical4. In the investigation of the whole plant of B. siamensis, a new alkaloid, 3-(4-hydroxyphenyl)-4-(3-methoxy -4-hydroxypheny…  相似文献   
223.
The insoluble species of Gd ( Ⅲ ) in human blood plasma were investigated by computer simulation. The distribution of the Gd(Ⅲ ) species was obtained. It was found that most of the Gd( Ⅲ ) ions were bound to phosphate to form precipitate GdPO4 at the concentration of 1. 000 10-7 mol/L and when the concentration of the Gd (Ⅲ ) increased to 3. 750 X 10-4 mol/L, in excess of the concentration of phosphate, the Gd ( Ⅲ ) ions were bound to carbonate to form another kind of precipitate, Gd2(CO3)3.  相似文献   
224.
李振武* 《物理学报》2013,62(9):96101-096101
从碳纳米管中Kondo效应的影响出发, 在有限温度下采用Anderson模型表征碳纳米管/磁杂质系统, 利用Landauer公式对磁杂质碳纳米管的电导和热电势进行研究, 得出和实验结果一致结论. 关键词: Kondo效应 碳纳米管 电输运特性  相似文献   
225.
Nitrobenzene is one of the most important chemical intermediates, for preparing drugs, pesticides and explosive etc. For more than a century, it has been commercially manufactured by reacting benzene with mixed acid in liquid phase under vigorous agitation. Despite the high efficiency, the mixed-acid process has some drawbacks, among which the huge amount of spent acid and wastewater are by far the most crucial, and this makes an alternative solution desirable. Nitration of benzene over sol…  相似文献   
226.
227.
Synthesis of the Complex Fluoride LiBaF_3 through a Solvothermal Process   总被引:1,自引:0,他引:1  
The complex fluoride LiBaF3 is solvothermally synthesized at 180℃ and characterized by means of X-ray powder diffraction, scanning electron microscopy, thermogravimetric analysis and infrared spectroscopy. In the solvothermal process, the solvents, mole ratios of initial mixtures and reaction temperature play important roles in the growth of the single crystal.  相似文献   
228.
Elsholtzia bodinieri Vant (Labiatae) named Feng-Wei-Cha or Dong-Zi-Su, is a Chinese medicinal plant, which is distributed in Yunnan and Guizhou Province of China. It is used in treatment of cough, headache, pharyngitis, fever and heptatitis1. In order to seek for the relative bioactive components, we studied the chemical constituents of E. bodinieri, which have not been reported in the literature. Two new triterpenoid glycosides, hederagenin-3-O-b-D-xylopyranoside (1), dodecandral-3-O…  相似文献   
229.
Cellulose is the most abundant resource of regenerative biomass on earth. But due to the complexity of its structure, its degradation mechanism was failed to fully understand. It makes a great limit to its full utility. In nature, wood decay is mainly accomplished by some wood-degrading fungi such as G.trabeum et al.. It is well-known that cellulases are the most important components of degrading cellulose. But because the cellulase activity is low, the complete utility of cellulose by e…  相似文献   
230.
Since Tang and Van Slyke reported the first double-layer organic electroluminescent (EL) device using Alq3 (q = 8-hydroxyquinolinyl) in 19871, organic EL devices have received a great deal of attention in view of their application as full-color flat-panel displays as well as academic interest2,3,4. There have been extensive studies of organic EL devices directed toward achieving high brightness and multi- or full-color emission, and in particular, improving the durability and thermal stabi…  相似文献   
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