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