{HEAD ~ A supported membrane} is a membrane cast on a substrate, {TAIL ~ preferably a nonwoven fabric} 
{ HEAD ~ A supported membrane } is a membrane cast on a substrate , { TAIL ~ preferably a nonwoven fabric }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL