Investigation process of change of Chladni figures on oscillating membrane under water layer

Present the experimental research of physical effect of transformation of Chladni figures on a membrane under water layer. Discovered, that the grains of sand concentrate not only in place with minimum amplitude oscillating, but also concentrate in place maximum amplitude oscillating too. For description this effect is obtained equation for a potential of radiative forces acting on a grain of sand in an acoustic field of an oscillating membrane.