ABSTRACT
Graphene covered metal nanoparticles constitute a novel type of hybrid material, which provides a unique platform to study plasmonic effects, surface-enhanced Raman scattering (SERS), and metal-graphene interactions at the nanoscale. Such a hybrid material is fabricated by transferring graphene grown by chemical vapor deposition onto closely spaced gold nanoparticles produced on a silica wafer. The morphology and physical properties of nanoparticle-supported graphene are investigated by atomic force microscopy, optical reflectance spectroscopy, scanning tunneling microscopy and spectroscopy (STM/STS), and confocal Raman spectroscopy. This study shows that the graphene Raman peaks are enhanced by a factor which depends on the excitation wavelength, in accordance with the surface plasmon resonance of the gold nanoparticles, and also on the graphene-nanoparticle distance which is tuned by annealing at moderate temperatures. The observed SERS activity is correlated with the nanoscale corrugation of graphene. STM and STS measurements show that the local density of electronic states in graphene is modulated by the underlying gold nanoparticles.
ABSTRACT
Families of organ donors are much more reluctant to approve donation of the corneas, face, and hands than of internal organs. The idea to "sacrifice" the face of a dead loved one is shocking to many. Moreover, most national laws, including Belgian laws, demand respect for the corpse. When mourners view an open coffin, visible parts such as the hands and face should appear normal. Hence, careful donor face reconstruction is required in a case of facial allotransplantation. We present a technique for donor face reconstruction that is both expedient and cost-effective. Instead of laboratory-cured silicone or acrylic polymers with internal and external coloration, an A-silicone impression material with a 2-minute set time and external colouring is used.
