Fig. 1From: Assessment of the toxicity and carcinogenicity of double-walled carbon nanotubes in the rat lung after intratracheal instillation: a two-year studyCharacterization of test materials in suspension. A shows scanning electron microscopy images of (a) DWCNT and (b) MWCNT-7 fibers and B shows transmission electron microscopy images of (a) DWCNT and (b) MWCNT-7 fibersBack to article page