Fabricating a nanofiber ribbon or sheet with a process that includes providing a primary assembly by arranging carbon nanotube nanofibers in aligned arrays, the arrays having a degree of inter-fiber connectivity, drawing the carbon nanotube nanofibers from the primary assembly into a sheet or ribbon, and depositing the sheet or ribbon on a substrate.

Embodiments of the present invention provide methods of preparing functionalized graphene nanoribbons by (1) exposing a plurality of carbon nanotubes to an alkali metal source in the presence of an aprotic solvent, wherein the exposing opens the carbon nanotubes; and (2) exposing the opened carbon nanotubes to an electrophile to form functionalized graphene nanoribbons. Such methods may also include a step of exposing the opened carbon nanotubes to a protic solvent in order to quench any reactive species on the opened carbon nanotubes. Further embodiments of the present invention pertain to graphene nanoribbons formed by the methods of the present invention. Additional embodiments of the present invention pertain to nanocomposites and fibers containing the aforementioned graphene nanoribbons.

Apparatuses for manipulating a color displayed by an article of wear comprising iron oxide colloidal nanocrystals arranged within chains are described, The apparatus includes (a) a magnetic field source, wherein a strength of a magnetic field generated by the magnetic field source is tunable to control the color displayed by the article of wear, and (b) an energy source, wherein energy generated by the energy source is applied to at least some of the chains of nanocrystals to soften materials within the article of wear immediately surrounding the chains of nanocrystals to which the energy is applied.

A process of producing a yarn, ribbon or sheet comprising nanofibers that includes infiltrating a liquid into the yarn, ribbon or sheet and evaporating the liquid from the yarn, ribbon, or sheet to strengthen the yarn, ribbon or sheet. The yarn, ribbon, or sheet can be formed by solid-state draw from a carbon nanotube forest.