title: Rayleigh-Benard convective instability: concentration Rayleigh number for isothermal passive transmembrane transport processes.
abstract: We derive a formula of the concentration Rayleigh number for isothermal membrane transport processes. The formula include diffusive permeability coefficient (omega ks), concentration polarization coefficient ([symbol: see text] ki) and solution parameters: density (rho), kinematic viscosity (nu), diffusion coefficient (Dks). Coefficients omega ks and [symbol: see text] ki were determined for configurations A and B of the single-membrane cell system, which consisted a flat polymeric membrane and glucose in 0.2 mol.l-1 aqueous ethanol solutions. In configuration A water was placed in compartment above the membrane and the solution below. In configuration B the arrangement of water and solution was reversed. The results of calculation showed that critical value of concentration Rayleigh number (Rsi) in configuration A is (R1A)crit. = 277.1 and in the configuration B--(R1B) = 225.2.
authors.affiliation: Department of Biomedical Fundaments of Sport, Czestochowa University of Technology. ajslezek@zim.pcz.czest.pl
authors.forename: Andrzej
authors.initials: A
authors.lastname: Slezak
mesh_terms: D001696:Biomechanical Phenomena; D002463:Cell Membrane Permeability; D018481:Convection; D004058:Diffusion; D000431:Ethanol; D005947:Glucose; D008567:Membranes, Artificial; D008954:Models, Biological; D015233:Models, Statistical; D011108:Polymers; D012996:Solutions / Q000737:chemistry*; D013696:Temperature; D014783:Viscosity
chemical_list: D008567:Membranes, Artificial; D011108:Polymers; D012996:Solutions; D000431:Ethanol; D005947:Glucose