???? ???
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???? ??? ??????? ??? ???? ???? ???? ?????, ??? ????? ??? ?????, ???? ??? ??? ?? ????? ??? ?????, ???? ??? ???? ??? ??? ????? ???? ????? surfactants ?? frictional ???? ?? ?? ??? ????? ??? ?? ????? ?? ??? ??? ?? ??? ????? ???, ?? ??? ?? ??????? ?????, ?? ?????, ??? ????? ?? ????? ??.
