In particular, embodiments of the invention relate to directing {HEAD ~ growth} of {TAIL ~ carbon nanotubes} 
In particular , embodiments of the invention relate to directing { HEAD ~ growth } of { TAIL ~ carbon nanotubes }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL