Adopts a completely original approach to the study of processes of mass transfer. In contrast to the usual approach, based on the concept of continuum media and the theory of heat and mass transfer, the topic is considered from a new viewpoint, taking into account the heterogeneous dispersal state of porous bodies. The author bases his discussion on the theory of surface forces and microhydrodynamic analysis of the processes of mass transport of gases, liquids and vapors, providing the reader with a systematic account of liquid/solid and gas/solid interfaces. Topics treated in this book include structural peculiarities, equilibrium and properties of liquids in porous bodies. Various mechanisms of mass transfer are considered, including liquid flow in pores and films, gas diffusion, combined transfer of liquid and vapor, convective diffusion in solutions, structure formation, capillary phenomena, and wetting. This unique book provides a wealth of information from the former Soviet Union, which will be of great interest to chemists, physicists and materials scientists, as well as industrialists working with a variety of different products in which disperse systems and porous bodies are important.