Solvent effects effective sink approximation

There has been a large number of theoretical studies since the inspiring work of Zusman devoted to dynamical solvent effects or, more generally, to effects associated with the competition between electronic transitions at strong coupling and various relaxation modes in the system [76-144]. Ovchinnikova [79] introduced an effective sink approximation to incorporate fast classical vibrational modes into the stochastic model of ET. She... 

Small quantities of NAPL can move into porous media under both gravity and capillary effects and can become essentially immobilized, due to discontinuities that develop in the NAPL as it spreads out these discontinuities are very much like the ones formed in water films in very dry porous media. Discontinuities prevent flow of NAPL from one region to another the amount of NAPL present when flow stops is called the residual saturation. The effect can be likened to that of water breaking into discontinuous, discrete droplets on the bottom of a greasy kitchen sink, thereby preventing flow of the last drops of water down the drain. (In this domestic example the water, not the grease film, is the discontinuous phase.) Residual saturation depends on soil texture and on the surface tension (cr) between the NAPL and water this surface tension is approximately 30 to 50 dyn/cm for many immiscible solvents and fuels. Residual saturation also depends on the initial water content of the porous media when the NAPL is introduced. 

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