Thermal diffusion in mixtures of helium with argon, neon, nitrogen and carbon dioxide and of neon with argon

Abstract

A new apparatus is described for the measurement of the concentration dependence of the thermal diffusion factor for the systems Ar + He, Ar + Ne, Ne + He, N₂+ He and CO₂+ He at mean temperature 306 K and a pressure of 51.3 kPa. Some measurements were made at pressures up to 304 kPa and others at a mean temperature of 278.5 K. The technique which employs matched pairs of thermistors as sensing elements for concentration, has significant advantages over previous methods and has yielded results with a precision at least equal to those previously reported.