https://doi.org/10.1351/goldbook.M03753
Spontaneous (irreversible) process of transfer of mass across non-homogeneous fields. The driving force can be difference in concentration (in liquids) or @[email protected] (in gases) of the component. In fluids, mass transfer may be enhanced by turbulent flow. In biological systems, mass transfer through membranes may result from normal @[email protected], facilitated @[email protected] or @[email protected]