INVESTIGATING DIMENSIONAL KINETIC EFFECTS ON THE BASIS OF MICROSCOPIC OBSERVATIONS OF THE EVOLUTION OF AN ENSEMBLE OF DROPLETS

The influence of geometric characteristics on the properties of a substance and the dynamics of physicochemical processes is manifested in the form of dimensionless effects which turn out to be substantial in many natural and technological processes. Investigating dimensional kinetic effects is complicated by the difficulty with obtaining experimental data on the state of individual dispersed particles of nano-, pico-, and femtoliter volumes. This problem is solved by the proposed procedure which is based on obtaining and analyzing a sequence of microphotographs of a polydisperse ensemble of droplets. A result is the construction of kinetic curves describing the behavior of a substance in variously sized droplets with comparable conditions. The analysis of the kinetic curves allows obtaining quantitative characteristics necessary to reveal the dimensional dependence of the physicochemical characteristics of the substance, to determine the kinetic parameters of chemical reactions, and to construct mathematical models of the processes in disperse systems. Observations of the ensembles of droplets have revealed a number of unusual kinetic effects ("non-Ostwald" behavior, oscillatory phase transformations "gas–liquid–crystal," and the formation of satellite droplets)

Author:  V. B. Fedoseev, E. N. Fedoseeva
Keywords:  dimensional effects, modeling, physicochemical processes, an ensemble of particles, analysis of images, microscopy
Page:  1005