communications of the "van der waalsfund" rapid expansion of compressed gas behind a piston, the effect of molecular interaction : The expansion of nitrogen / [by] A. Michels, S.J. Jacobs, Z.I. … communications of the "van der waals-fund" rapid expansion of compressed gas behind a piston, the effect of molecular interaction / by A. Michels, S.J. Jacobs, Z.I. Slawsky