title: Flow-enhanced molecular reorientations and interfacial slip probed by field-cycling NMR relaxometry in microscopic pores.
abstract: It is shown that hydrodynamic flow has an effect on spin-lattice relaxation in water filled into a porous monolithic silica material. This is a rotational analogue of translational hydrodynamic (or Taylor-Aris) dispersion arising from incoherent Brownian motion in combination with coherent flow. The effect is demonstrated with the aid of field-cycling NMR relaxometry and confirmed by theoretical considerations. The results directly verify bulk mediated surface diffusion and reveal interfacial slip at fluid-solid interfaces.
authors.affiliation: Sektion Kernresonanzspektroskopie, Universität Ulm, 89069 Ulm, Germany.
authors.forename: Carlos
authors.initials: C
authors.lastname: Mattea
authors.forename: Rainer
authors.initials: R
authors.lastname: Kimmich