Mean profiles of scalar properties close to moving gas-liquid interfaces subjected to turbulence are quantified using Random Square Waves (RSW). The condition of stationary turbulent transfer allows reducing the third order nonlinear governing equation successively to a second order and to a first order equation, which admits theoretical integration, furnishing the set of solutions analyzed in the present study. It is shown that different solutions may apply to different parts of the calculation domain (physical domain). It is also shown that the stationary problem admits a linear profile close to the gas-liquid interface, while a nonlinear function describes the mean properties apart from the interface.