Abstract
In the atmospheres of helium-argon mixture at normal pressure with varying mixing ratio of the gases, ice crystals were formed by seeding of silver iodide smoke. Crystals were grown in a state of gravity fall and fell to the bottom of a cold chamber. These crystals were examined directly without the use of replication technique by a microscope that was set under the bottom window of the chamber. It has been revealed that features of crystal growth vary with mixing ratio of helium and argon.
The revealed variation of growth with respect to the mixing ratio of the gases can not be attributed to the difference in a state of fall of the crystals in the chamber because the molecular viscosity varies little with the mixing ratio of helium and argon. Instead, that can be attributed to the difference in the diffusion coefficients of water vapor and the thermal conductivities of the carrier gas, because the both parameters vary greatly with the mixing ratio of the gases.