Fabrication and Experimental Analysis of Axially Oriented Nanofibers.

A novel design of a laboratory built axially rotating collector (ARC) having capability to align electrospun nanofibers have been described. A detailed morphological comparison of such nanofibers orientation and their geometry is done using scanning electron microscopy (SEM). For comparison various polymeric solutions were electrospun on conventional static collector as well as ARC.

Functionalized low defect graphene nanoribbons and polyurethane composite film for improved gas barrier and mechanical performances.

A thermoplastic polyurethane (TPU) composite film containing hexadecyl-functionalized low-defect graphene nanoribbons (HD-GNRs) was produced by solution casting. The HD-GNRs were well distributed within the polyurethane matrix, leading to phase separation of the TPU. Nitrogen gas effective diffusivity of TPU was decreased by 3 orders of magnitude with only 0.

Fluorinated graphene oxide; a new multimodal material for biological applications.

Fluorinated graphene oxide (FGO) is reported for the first time as a magnetically responsive drug carrier that can serve both as a magnetic resonance imaging (MRI) and photoacoustic contrast agent, under preclinical settings, and as a type of photothermal therapy. Its hydrophilic nature facilitates biocompatibility. FGO as a broad wavelength absorber, with high charge transfer and strong non-linear scattering is optimal for NIR laser-induced hyperthermia.

Structure of excited-state transitions of individual semiconductor nanocrystals probed by photoluminescence excitation spectroscopy.

We perform for the first time photoluminescence excitation (PLE) studies of individual nanocrystals (NCs) that reveal the structure of excited-state transitions not obscured by ensemble averaging. Single-NC PLE spectra strongly deviate from a traditional idealized picture of sharp, quasiatomic resonances. We detect only a few relatively narrow transitions (3-4 meV) at the band edge, while at higher spectral energies, we observe a broad structureless feature separated from the band-edge peaks by a >50 meV "minigap.