title: Transient surface tension in miscible liquids.
abstract: Evidence of the existence of a transient surface tension between two miscible fluid phases is given. This is done by making use of a density matched free of gravity perturbations, binary liquid of isobutyric acid and water, which presents a miscibility gap and is studied by light scattering. The experiment is performed very near the critical point of the binary liquid, where the diffusion of phases is extremely slow. The surface tension is deduced from the evolution of the structure factor obtained from low angle light scattering. The latter evolution is successfully analyzed in terms of a local equilibrium diffusive approach that makes explicit how the surface tension decreases with time.
authors.affiliation: Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), Ecole Supérieure de Physique et de Chimie Industrielles (ESPCI), 10 rue Vauquelin, 75231 Paris Cedex 5, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Lacaze
authors.forename: Patrick
authors.initials: P
authors.lastname: Guenoun
authors.forename: Daniel
authors.initials: D
authors.lastname: Beysens
authors.forename: Michel
authors.initials: M
authors.lastname: Delsanti
authors.forename: Philippe
authors.initials: P
authors.lastname: Petitjeans
authors.forename: Pascal
authors.initials: P
authors.lastname: Kurowski