Fig. 2From: Hydrolytic Unzipping of Boron Nitride Nanotubes in Nitric AcidTransmission electron microscopic images of a the purified boron nitride nanotubes and samples obtained by refluxing in nitric acid for b 3 h, c 12 h, and d 24 h; enlarged images of b, c, and d indicated partially unzipped BNNTs, respectivelyBack to article page