Phrynopus AmphibiaWeb keeps "Noblella" in Strabomantidae/Strabomantinae, a family/subfamily no longer recognized by the Amphibian Species of the World. "Phrynopus" are small to medium-sized frogs, from snout–vent length in "Phrynopus auriculatus" to in "Phrynopus kauneorum". Head is narrower than the body. Differentiated tympanic membrane and tympanic annulus are usually absent, except in "Phrynopus auriculatus" and "Phrynopus peruanus", two basal species. Dorsum is smooth to pustulate. Venter is smooth or areolate. There are 26 species in this genus: Phrynopus Phrynopus is a genus of frogs of the Craugastoridae family. Their common name is Andes frogs. They are endemic to Peru and inhabit the
Membrane gas separation when the pores in the polymer membrane appear and disappear faster relative to the movement of the particles. In a typical membrane system the incoming feed stream is separated into two components: permeant and retentate. Permeant is the gas that travels across the membrane and the retentate is what is left of the feed. On both sides of the membrane, a gradient of chemical potential is maintained by a pressure difference which is the driving force for the gas molecules to pass through. The ease of transport of each species is quantified by the permeability, P. With the assumptions of