Capillary force of a novel skew-grooved wick structure for micro heat pipes

In order to improve the capillary force of grooved wick, a novel skew-grooved wick structure was proposed for micro heat pipes. Risen meniscus experiments were carried out to research the capillary force of the skew-grooved and rectangle-grooved wick and a comparison of capillarity between the two wick structures was explored. A theoretical capillary force model of skew-grooved wick structure was also developed to calculate its effective capillary radius by comparing with the rectangle-grooved wick. From the experimental results, the maximum capillary force of the skewed-grooved wick is 8.62% larger than that of the rectangle-grooved wick. From the theoretical analysis, because the skewed-grooved wick has a smaller effective capillary radius, its maximum capillary force is 8.64% larger than that of the rectangle-grooved wick. The results indicate that the skew-grooved wick provides larger capillary force than the rectangle-grooved wick.     

正交回归多元标准加入光度法同时测定混合稀土组分

应用正交回归设计的多元标准加入法 ,在偶氮胂 - OP- HAc- Na Ac显色体系中 ,研究了具有代表性、且相互干扰严重的镧、钆、镝三种稀土组分的混合溶液中同时测定镧、钆、镝的方法。实验证明 ,三种稀土浓度在1× 10 - 7mol· L- 1～ 1× 10 - 5m ol· L- 1范围内 ,同时测定的相对标准偏差低于 4 .2 %。     

变频调速电机自启动的改进探讨

分析聚丙烯厂Ｃ－２０３变频调速电机原设计自启动存在的问题，介绍改进后增设的刹车装置的工作原理及使用效果。