Under the influence of second-order gradients in the temperature, an anisotropy in the rotational angular momenta in a gas can be set up, giving rise to a birefringence. Preliminary measurements on this effect, called heat-flow birefringence, are reported. An interpretation of the results is...

An alignment of the rotational angular momenta of gas molecules occurs in the presence of a gradient in the stream velocity of the gas. This can be measured as a birefringence. Measurements on gases of linear chain molecules are presented. The results confirm the general trend found earlier for...

Preliminary measurements of the nonequilibrium velocity distribution function in a heat conducting gas have been carried out using a Doppler broadened absorption line. The experimental technique, which uses the coincidence of a Stark tunable line of NH2D and the CO2 P(20) laser frequency, is...

In an earlier paper, an alignment of the rotational angular momenta of gas molecules produced by a gradient in the stream velocity has been shown to cause a measurable birefringence in the gas. The present paper reports an extension of these measurements to mixtures, specifically N2 and HD with...

Experimental flow birefringence data for para hydrogen-noble gas mixtures at 293 K are presented. The consistency with available data on depolarized Rayleigh line broadening is discussed. The results disagree with recent close coupled calculations by McCourt.

The influence of a magnetic field on a Knudsen gas flow was studied experimentally. An increase in drag, or in flow resistance, of the order of 10-5 was found for several polyatomic gases. The effect originates from non-spherical gas-surface scattering.

The influence of a magnetic field on the shear viscosity of N2 and N2-noble gas mixtures was measured at 295 K in the moderately rarefied gas regime, where the mean free path is non-negligible. For all systems a similar pressure dependence was observed with the Knudsen number providing a...

In a viscous flow of rarefied gas mixture containing polyatomic molecules, transverse diffusion can occur under the influence of an external magnetic field. This “viscomagnetic diffusion flux”, which has its origin in the angular momentum dependent polarization produced by nonspherical...

Stereospecific interaction between optical isomers is investigated by studying its impact on gas phase transport properties at room temperature. Using differential techniques, both the thermal conductivity and the viscosity of optically pure samples were compared with those of the racemic...

For a polyatomic gas simple expressions have been derived for the thermal conductivity as well as for the variation of the thermal conductivity as a function of an external field. This has been achieved by using the total heat transport as a trial function in the kinetic theory instead of the...