The metal may be in {HEAD ~ the form} of a particulate metal or {TAIL ~ atomically dispersed metal} or both 
of
The metal may be in { HEAD ~ the form } of a particulate metal or { TAIL ~ atomically dispersed metal } or both
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH