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1,2-丙二醇水溶液在不同温度下的超额摩尔体积黏度和热容 总被引:2,自引:0,他引:2
Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity was investigated. The values of VE and E were fitted to the Redlich-Kister equation. Good agreement was observed. The excess volumes are negative over the entire range of composition. They show an U-shaped-concentration dependence and decrease in absolute values with increase of temperature. Values of E are negative over the entire range of the composition, and has a trend very similar to that of VE . The analysis shows that at any temperature the specific heat of mixture is a linear function of the composition as x1 > 20%. All the extended lines intersect at one point. An empirical equation is obtained to calculate the specific heat to mixture at any composition and temperature in the experimental range. 相似文献
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以3-溴吡啶和二乙基甲氧基硼烷为原料合成了二乙基(3-吡啶基)硼烷。探索了反应时间、反应温度、反应配比等反应条件对于反应收率的影响。结果表明最适宜合成工艺条件为:反应温度0~5 ℃,反应时间6 h,二乙基甲氧基硼烷滴加时间30 min,物料配比n(3-溴吡啶)∶n(二乙基甲氧基硼烷)为0.9∶1.0,物料配比n(异丙基氯化镁)∶n(二乙基甲氧基硼烷)为1.0∶1.0。在最适宜工艺条件下制得产品为白色固体,熔点为172~175 ℃,产率在81%以上。并通过质谱和红外光谱对其进行了结构表征。 相似文献
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