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The lowest temperature at which water---KCl---2-propanol mixtures cannot be split has been determined as 25.3°C. Seven diagrams of liquid-liquid-solid equilibria for the ternary system water---potassium chloride-2-propanol around this temperature have been measured and the transition between their two different shapes has been studied. 相似文献
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The first synthesis of justicidone (4-(1',3'-Benzodioxol-5'-yl)-6-methoxynaphtho[2,3-c]furan-1,5,8(3H)-trione) was carried out from piperonal, as a starting compound, through a lineal process using well known reactions. 相似文献
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Pérez JA Boluda C López H Trujillo JM Hernández JM 《Chemical & pharmaceutical bulletin》2004,52(9):1123-1124
Candida antarctica lipase (CAL) catalyses the regioselective acetylation of the 10-hydroxyl group of 10-hydroxyoleoside dimethyl ester, a secoiridoid glucoside, using THF as a solvent and ethyl acetate or vinyl acetate as acetyl group suppliers. Two acetyl derivatives at 3'- and 6'-sites of the glucosidic ring of 10-acetoxyoleoside dimethylester, not previously described, were obtained by acetylation in the same conditions. 相似文献
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The technique of ferromagnetic resonance at 23 GHz has been used to determine the first three anisotropy constants of pure Ni down to 4.2K. A temperature and orientation dependent linewidth has also been observed. 相似文献
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A. Alegría R. Barberá R. Boluda F. Errecalde R. Farré M. J. Lagarda 《Fresenius' Journal of Analytical Chemistry》1991,339(9):654-657
Summary The cadmium, lead and nickel content of soils of four agricultural areas exposed to different degrees of environmental pollution and vegetables grown there were measured by Atomic Absorption Spectrophotometry (AAS). In order to ascertain the possible relationship between the heavy metal content of soils (total and extractable) and of vegetables grown in them, the correlation between the two was calculated. The highest correlation values between metal content of soil and vegetables are these corresponding to nickel: the total metal content in soils and leaves-stems are linear (p<0.01). The extractable metal content of soils and leaves-stems are linear (p<0.1). Therefore, soil seems to be the main contributor to nickel content of plants (leaves-stems). In the case of cadmium a statistically significant linear correlation (p<0.01) was observed between total metal content in soil and in leaves-stems and a negative one between extractable metal content of soils and that of roots-bulbs. For lead a negative correlation was found between extractable metal content of soils and leaves-stems. In any case, the lead content of soils is not the main factor that influences the lead content of vegetables. Anthropogenic and environmental factors play a more important role than the lead in soils in the lead content of vegetables. 相似文献
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