2239211 SWCNT single-walled carbon nanotube 1048 3504500 SWNT single-walled carbon nanotube 656 3503833 SWCN single-walled carbon nanotube 14 3418661 SCNT single-walled carbon nanotubes 5 450057 SW single-walled carbon nanotubes 4 2245264 SWNCT single-wall carbon nanotube 1