A wide range of chemical/physical processes can be performed by an ultrasonic desintegrator. such as disruption of cells and bacteria, preparation of emulsions and dispersions, homogenizing of liquids and comminution of crystalline material. The size reduction by ultrasonics in liquid phase of different materials such as cyclo-1,3,5-trimethvlene-2,4,6-trinitramine, cyclotetramethylene tetranitramine, 5-nitro-1,2,4-triazol-3-one, hexanitrostilbene (HNS), ammonium nitrate and sodium chloride (NaCl) was experimentally investigated in batch process. Changes in the mean particle size and particle size distribution during the comminution by ultrasound could be observed. The use of different ultrasonic intensities yields different size reduction results. Induction of ultrasound into a liquid phase was optically investigated in liquids of different viscosity. (C) 2004 Elsevier B.V. All rights reserved.