arXiv subjects

V. P. Revyakin

Publications and source records attributed to V. P. Revyakin.

3 recordsLinked to original sources

arXiv2004

Heat transfer in gama-phase of oxygen

The isochoric thermal conductivity of gama-O2 has been studied on samples of varying density in the temperature interval from 44 K to the onset of melting. The thermal conductivity of nearly free sample decreases at rising temperature along the isochores. It is shown that the absolute value of thermal conductivity in the gama-phase of O2 is close to its lower limit and most of the heat is transported by "diffusive" modes. The growth of thermal conductivity in gama-O2 is attributed to the decay of the phonon scattering at the rotational excitations of the molecules and at the short-range magnetic order fluctuations at rising temperature.

cond-mat.dis-nn↗

arXiv2004

Isochoric thermal conductivity of solid nitrogen

The isochoric thermal conductivity of solid nitrogen has been investigated on four samples of different densities in the temperature interval from 20 K to the onset of melting. In alfa-N2 the isochoric thermal conductivity exhibits a dependence weaker than 1/T; in beta-N2 it increases slightly with temperature. The experimental results are discussed within a model in which the heat is transported by low-frequency phonons or by "diffusive" modes above the mobility boundary. The growth of the thermal conductivity in beta-N2 is attributed to the decreasing "rotational" component of the total thermal resistance, which occurs as the rotational correlations between the neighboring molecules become weaker.

cond-mat.dis-nn↗

arXiv2003

Heat transfer by mobile low-frequency phonons and "localized" modes in cryocrystal solutions

The temperature and volume dependences of the thermal conductivity of solid Kr(1-x)Xe(x)solution are analyzed within the model in which heat is transferred by mobile low-frequency phonons; above the phonon mobility edge this is done by "localized" modes migrating randomly from site to site. The phonon mobility edge (w0)is determined from the condition that the phonon mean -free path restricted by Umklapp processes and point defects scattering cannot be smaller than one-half the phonon wavelength. The Bridgman coefficient is the weighted - mean over these modes whose volume dependences differ widely. It is shown that the amount of heat transferred by the "localized" modes above 100 K is quite large even in pure Kr and it increases with rising temperature and impurity concentration.

cond-mat.mtrl-sci↗