Euler, vis viva, and equilibrium

Euler’s ‘On the force of percussion and its true measure’, published in 1746, shows that not only had the issue of vis viva not been settled, but that the concepts of inertia and even force were still very much up for grabs. This paper details Euler’s treatment of the vis viva problem. Within those details we find differences between his physics and that of Newton, in particular the rejection of empty space and reduction of all forces to the operation of inertia through contact. One can further see how Euler’s philosophy of science embraced explanation through mechanisms and equilibrium conditions.     

辽河原油直馏油常减压汽液平衡的实验研究与关联

利用自建的流动型汽－液平衡装置，分别测定了辽河原油直馏油在常减压不同压力和温度下共１５套汽－液平衡数据。按假多元系法处理获得２２０组相平衡常数。在此基础上提出了计算假组分相平衡常数的５个经验关联式并进行了泡、露点温度预测。这些关联式所用物性参数少，易于获得，可供工程实际应用。此外还就实测ＥＦＶ曲线与用ＡＰＩ推荐方法转换的相同压力下的ＥＦＶ曲线作了比较。