title: Study of gas-fluidization dynamics with laser-polarized 129Xe.
abstract: We report initial NMR studies of gas dynamics in a particle bed fluidized by laser-polarized xenon (129Xe) gas. We have made preliminary measurements of two important characteristics: gas exchange between the bubble and emulsion phases and the gas velocity distribution in the bed. We used T2* contrast to differentiate the bubble and emulsion phases by choosing solid particles with large magnetic susceptibility. Experimental tests demonstrated that this method was successful in eliminating 129Xe magnetization in the emulsion phase, which enabled us to observe the time dependence of the bubble magnetization. By employing the pulsed field gradient method, we also measured the gas velocity distribution within the bed. These results clearly show the onset of bubbling and can be used to deduce information about gas and particle motion in the fluidized bed.
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA.
authors.forename: Ruopeng
authors.initials: R
authors.lastname: Wang
authors.forename: Matthew Scott
authors.initials: MS
authors.lastname: Rosen
authors.forename: Donald
authors.initials: D
authors.lastname: Candela
authors.forename: Ross William
authors.initials: RW
authors.lastname: Mair
authors.forename: Ronald Lee
authors.initials: RL
authors.lastname: Walsworth
mesh_terms: D004655:Emulsions; D005740:Gases / Q000737:chemistry*; D007834:Lasers; D009682:Magnetic Resonance Spectroscopy; D014835:Volatilization; D014979:Xenon Isotopes
chemical_list: D004655:Emulsions; D005740:Gases; D014979:Xenon Isotopes