tinuously deformed surface. It is a purpose of this work to
The surface of a soluble monolayer (Brij-58 solutions) in equilibconsider this convection term and to analyze the experimenrium is compressed with a constant speed, and the surface tension tal data.
with time is measured. To analyze the experimental data the convective diffusion equation is integrated and thereafter approxi-THEORY mated. The agreement between theoretical predictions and experimental data was good, using Gibbs elasticity and diffusion relax-
The surface of a surfactant solution in equilibrium with ation time as adjustable parameters. From these data the elasticity the bulk is initially equal to V 0 . This surface is now comof the monolayer as a function of the effective time is obtained. For pressed with a constant linear speed dV/dt, and the variation a micellar system, the bulk region adjoining the surface becomes of the surface with time, t, is given by the expression oversaturated, after threshold micellization sets in. The Gibbs elasticity and the diffusion relaxation time resulting from experimental data are compared with those obtained from the adsorption iso-
therm. The agreement is poor. This is discussed by considering that the Gibbs elasticity and the diffusion relaxation time require second differentials of the equilibrium surface tension concentrawhere dV/dt is negative.
tion curve.