title: Water-air saturation changes in restricted geometries studied by proton relaxation.
abstract: The results are reported of a systemic T1 and T2 investigation of natural (sandstones) and artificial (microporous porcelain) porous media, after each step of a water desaturation process by centrifugation in air. The analysis of the relaxation curves permitted distinguishing well the different behaviour of the natural samples as compared to the artificial ones, which can be explained by the different pore structures. In both kinds of samples the evolution of the relaxation time distributions yielded a clear picture of the changes of the water distribution in the pore framework following the displacement process, until irreducible water saturation was attained. The results are compatible with the assumption of a fixed amount of surface area contributing to the relaxation of decreasing amounts of fluid as SW is reduced.
authors.affiliation: University of Bologna, Istituto di Scienze Minerarie, Italy.
authors.forename: G C
authors.initials: GC
authors.lastname: Borgia
authors.forename: A
authors.initials: A
authors.lastname: Brancolini
authors.forename: R J
authors.initials: RJ
authors.lastname: Brown
authors.forename: P
authors.initials: P
authors.lastname: Fantazzini
authors.forename: G
authors.initials: G
authors.lastname: Ragazzini
mesh_terms: D000388:Air; D003776:Dental Porcelain; D009682:Magnetic Resonance Spectroscopy; D016062:Porosity; D014867:Water
chemical_list: D014867:Water; D003776:Dental Porcelain