Fig. 8

a Plots of pure gas permeances of urea-containing PSQ membranes measured at 200 °C versus gas kinetic diameter. b Normalized data and Knudsen prediction based on helium gas permeance

a Plots of pure gas permeances of urea-containing PSQ membranes measured at 200 °C versus gas kinetic diameter. b Normalized data and Knudsen prediction based on helium gas permeance