TECHNIQUE OF RESEARCH OF ANISOTROPY OF SPEE OF ULTRASOUND IN NEMATIC AT HIGH PRESSURES

Abstract

The technique of research of anisotropy of speed of ultrasound in nematic Н-37 in
a temperature interval from 25 to 70 0С is presented at various pressure. In all investigated
temperature intervals of existence of a nematic mesophase, speed of ultrasound is more in
case of parallel orientation of a vector of a magnetic induction and a wave vector in comparison
with perpendicular orientation. In the distance (ƒТ≥10К) from phase transition relative
anisotropy of speed of ultrasound practically doesn't depend on temperature and has
small value. The maximum influence of a magnetic field on speed of ultrasound takes place
for ƒТ=5 to from enlightenment temperature.