{TAIL ~ The extractor} comprises {HEAD ~ a microporous dialysis membrane tube} filled with cation or anion exchange resin beads 
{ TAIL ~ The extractor } comprises { HEAD ~ a microporous dialysis membrane tube } filled with cation or anion exchange resin beads
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH