8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

P2.20Tue 611:23-14:00Long-lived sub-microscopic bubbles in very dilutedalkali halides water solutionsEugène Duval, 1 Sergey Adishchev, 1 Sergey Sirotkin, 1 and Alain Mermet 11 LPCML, Université Lyon 1, B Kastler Campus de La Doua, 43, Bld du 11 Novembre69622, Villeurbanne cedex, FranceSolutions in pure water of LiCl or NaCl, from 10 −2 g cm −3 to 10 −18 g cm −3 , were studied byRayleigh/Brillouin light scattering. After each centesimal dilution, the solutions were vigorouslyshaken. The Landau-Placzek ratio, R/B, of the Rayleigh intensity over the total Brillouin one wasmeasured thanks to the dynamically controlled stability of the used Fabry-Perot interferometer.R/B decreased with the dilution from 10 −2 g cm −3 down to 10 −6 g cm −3 , and increased to reacha maximum in the 10 −10 − 10 −14 g cm −3 interval. With the dilution, the Rayleigh scatteringthat is due to ion concentration fluctuations decreased. From a concentration of 10 −6 g cm −3it increased with the dfilution because of the presence of heterogeneities that correspond tolong-lived sub-microscopic bubbles of air, which were created by the shaking. The long lifetimeof these bubbles and the effect on them of dissolved salts, even at very low concentration, are inagreement with the model of agglomerated electrically charged nanobubbles [1].[1] N. F. Bunkin et al., J. Chem. Phys. 130, 134308 (2009)20