title: Effects of pore walls and randomness on phase transitions in porous media.
abstract: We study spin models within the mean field approximation to elucidate the topology of the phase diagrams of systems modeling the liquid-vapor transition and the separation of 3He-4He mixtures in periodic porous media. These topologies are found to be identical to those of the corresponding random field and random anisotropy spin systems with a bimodal distribution of the randomness. Our results suggest that the presence of walls (periodic or otherwise) are a key factor determining the nature of the phase diagram in porous media.
authors.affiliation: Department of Physics and Materials Research Institute, 104 Davey Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Marek
authors.initials: M
authors.lastname: Cieplak
authors.forename: Amos
authors.initials: A
authors.lastname: Maritan
authors.forename: Michael R
authors.initials: MR
authors.lastname: Swift
authors.forename: Flavio
authors.initials: F
authors.lastname: Toigo
authors.forename: Jayanth R
authors.initials: JR
authors.lastname: Banavar