Individual, unsupported scales of two male butterflies with dorsal blue and ventral green color were compared by
microscpectrometric measurements, optical and electronic microscopy. All the scales are colored by photonic band gap
type materials built of chitin (n = 1.58) and air. The different scales are characterized by different degrees of order from
fully ordered single crystalline blue scales of the Cyanophrys remus butterfly through polycrystalline green scales on the
ventral side of the same butterfly, to the most disordered dorsal blue scales of the Albulina metallica, where only the
distance of the first neighbors is constant. The different scale nanoarchitectures and their properties are compared.
The functionalization of carbon nanotubes (CNTs) is important both for composite - to improve load transfer between CNTs and matrix - and nanoelectronic applications - to interlink individual nanotubes in a network. Oposite to earlier results, complete coverage of CNT surface with functional groups was achieved. The distribution of functional groups on the nanotube surface was investigated using STM and TEM. The influence of functional groups on the electron density of states of the nanotubes was studied with scanning tunneling spectroscopy (STS).
We performed scanning tunneling microscopy (STM) measurements on few wall carbon nanotubes that exhibited changing diameter. Such change in the diameter may occur if non-hexagonal carbon ring configurations are introduced in the nanotube walls. A few-walled nanotube knee of 4 degrees, with different diameter values on the two sides of the knee was imaged by STM. Theoretical model structures  of single-wall carbon nanotubes show that a bend of 4 degrees may occur when a pentagonal and a heptagonal carbon ring is incorporated side by side in the hexagonal nanotube structure. Scanning tunneling spectroscopic (STS) measurements show that additional electronic states are present in the energy gap in the region where the bend occurs. We also performed STS measurements on a single-wall nanotube with conical tip. In agreement with theory, the results show that the energy gap in the tapered end is larger than in the nanotube.