| The thermal diffusion factors of equimolar ('4)He - ('20)Ne gaseous mixtures have been measured in a ten-tube trennschaukel at average temperatures of 82 K and 100 K. These measurements are at lower temperatures than any previously reported in the open literature and are in excellent agreement with theoretical calculations based on recently reported interatomic potential functions describing He-Ne interactions. Mixture compositions have been determined by means of thermal conductivity gauges using cytogenic thermistors mounted in the apparatus itself. This in situ analytical technique yields higher precision results than mass spectrometric analysis available for this work and, in addition, allows the theoretical expressions for the operating conditions of a trennschaukel to be checked. The approach to the steady state is found to be faster than predicted by theory, regardless of operating conditions. Qualitative agreement between theory and experiment is found for the effects of other operating conditions. |
