Researchers in the US have made a remarkable discovery about how an iron nanocrystal moves through a carbon nanotube that does not have a uniform diameter. They found that if the crystal meets a constriction in the tube, the crystal reforms, atom by atom, to fit through the constriction, without undergoing any melting or compression. According to the researchers, this behaviour could have many applications in nanomechanics and could possibly be used to synthesize small nanoparticles.

http://nanotechweb.org/cws/article/tech/53295