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对于Euler无穷小量εn,可以证明任给正数d<12 ,都存在自然数N ,使得当n>N时 ,dn <εn<12n。 相似文献
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将氯气制备与多个性质实验及尾气吸收综合在一起进行一体化创新设计,整个装置密闭,操作简单。该实验集微型化和综合性于一体,既节约试剂,现象明显,又可控速率,绿色环保,非常适合课堂演示。 相似文献
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Molar heat capacities of the pure samples of acetone,methanol and the azeotropic mixture composed of acetone,cyclohexane and methanol were measured by an adiabatic calorimeter from 78 to 320 K.The solid-solid andsolid-liquid phase transitions of the pure samples and the mixture were determined based on the curve of the heatcapacity with respect to temperature.The phase transitions took place at(126.16±0.68)and(178.96±1.47)K forthe sample of acetone,(157.79±0.95)and(175.93±0.95)K for methanol,which were corresponding to thesolid-solid and the solid-liquid phase transitions of the acetone and the methanol,respectively.And the phase tran-sitions occurred in the temperature ranges of 120 to 190 K and 278 to 280 K corresponding to the solid-solid andthe solid-liquid phase transitions of mixture of acetone,cyclohexane and methanol,respectively.The thermody-namic functions and the excess thermodynamic functions of the mixture relative to standard temperature of 298.15K were derived based on the relationships of the thermodynamic functions and the function of the measured heatcapacity with respect to temperature. 相似文献
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该文利用新的比较结果研究Banach空间二阶积一微分方程组初值问题解的存在性.即使在有限维空间,其结果也是新的. 相似文献
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该文利用新的比较结果研究Banach 空间二阶积-微分方程组初值问题解的存在性.即使在有限维空间, 其结果也是新的. 相似文献
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采用静态与动态实验方法,对聚天冬氨酸的阻垢性能进行了实验研究.静态实验研究表明,在溶液低于60℃的情况下,聚天冬氨酸具有优良的阻垢性能,硬度为600mg/L的溶液添加3mg/L聚天冬氨酸,阻垢率即可超过90%.在800mg/L硬度的情况下,在溶液温度30℃时添加6mg/L聚天冬氨酸,在溶液温度60℃时添加12mg/L聚天冬氨酸,阻垢率均可达到90%以上.CaCO3晶体的扫描电子显微镜结果表明,加入阻垢剂使CaCO3由质地坚硬的柱状晶体转变为松软的不定型体,容易被水冲走而不是沉积在换热表面.动态实验研究表明,成垢溶液添加阻垢剂之后,污垢热阻明显减小,换热表面基本不结垢. 相似文献
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