V izuchenii i opisanii perenosa veshchestv cherez podvizhnye granitsy sistem zhidkost"-zhidkost" dominiruet traditsionnyy podkhod, pri kotorom v kachestve dvizhushchey sily ispol"zuyut raznost" kontsentratsiy, svoystva faz schitayutsya neizmennymi vplot" do mezhfaznoy granitsy, a sama granitsa - ne imeyushchey tolshchiny. V to zhe vremya, ekstraktsiya neorganicheskikh veshchestv, pochti vsegda soprovozhdaetsya khimicheskimi reaktsiyami i takimi yavleniyami, kak gidrodinamicheskaya neustoychivost", samoproizvol"noe dispergirovanie, obrazovanie dispersnykh mezhfaznykh sloev, adsorbtsiya dispersnykh chastits, ikh koagulyatsiya i vozniknovenie strukturirovannykh mezhfaznykh plenok. Dannye protsessy formiruyut novuyu dinamicheskuyu mezhfaznuyu oblast", novye usloviya protekaniya reaktsiy i perenosa massy v ney. Issledovateli poka ogranichivayutsya lish" konstatatsiey fakta o nalichii fraktal"noy razmernosti u mezhfaznoy oblasti. Popytki opisaniya protsessov, proiskhodyashchikh v ney, natalkivayutsya na matematicheskie trudnosti. Odnako, perenos massy vo fraktal"nykh sredakh mozhno opisyvat" s pomoshch"yu differentsial"nykh uravneniy, soderzhashchikh drobnye proizvodnye. Predlagaemyy metod chislennogo resheniya takikh uravneniy pozvolil vpervye izvlech" informatsiyu o mezhfaznykh yavleniyakh.