Fig. 4From: Transparent Polyurethane Nanofiber Air Filter for High-Efficiency PM2.5 CaptureEvaluation of filtration efficiency of TPU fiber membrane. a Remove efficiency of PM of different sizes with TPU concentrations of 6 wt%, 8 wt%, 10 wt%, 12 wt%, 14 wt%, and 16 wt%, respectively. b PM2.5 removal efficiency of different concentrations of TPU fiber membranes. c–e PM through different diameter fiber membranesBack to article page