Dynamic forces between bubbles and surfaces and hydrodynamic boundary conditions.
A bubble attached to the end of an atomic force microscope cantilever and driven toward or away from a flat mica surface across an aqueous film is used to characterize the dynamic force that arises from hydrodynamic drainage and electrical double layer interactions across the nanometer thick intervening aqueous film. The hydrodynamic response of the air/water interface can range from a classical fully immobile, no-slip surface in the presence of added surfactants to a partially mobile interface in an electrolyte solution without added surfactants. A model that includes the convection and diffusion of trace surface contaminants can account for the observed behavior presented. This model predicts quantitatively different interfacial dynamics to the Navier slip model that can also be used to fit dynamic force data with a post hoc choice of a slip length.
Manor
Ofer
O
Particulate Fluids Processing Centre, University of Melbourne, Parkville, Victoria 3010, Australia.
Vakarelski
Ivan U
IU
Stevens
Geoffrey W
GW
Grieser
Franz
F
Dagastine
Raymond R
RR
Chan
Derek Y C
DY
D000388:Air; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D016503:Drug Delivery Systems; D004867:Equipment Design; D008823:Micelles; D018625:Microscopy, Atomic Force / Q000295:instrumentation / Q000379:methods*; D015233:Models, Statistical; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D055672:Static Electricity; D013499:Surface Properties; D013500:Surface Tension; D013501:Surface-Active Agents; D014465:Ultrasonics; D014867:Water / Q000737:chemistry
D008823:Micelles; D013501:Surface-Active Agents; D014867:Water