In recent years, near-nano (submicron) and nanostructured materials have attracted increasingly more attention from the materials community. Nanocrystalline materials are characterized by a microstructural length or grain size of up to about 100 nm. Materials having grain size of 0.1 to 0.3 mm are classified as submicron materials. Nanocrystalline materials exhibit various shapes or forms, and ...

We measured the phonon density of states (DOS) of nanocrystalline Fe by resonant inelastic nuclear g-ray scattering. The nanophase material shows large distortions in its phonon DOS. We attribute the high energy distortion to lifetime broadening. A damped harmonic oscillator model for the phonons provides a low quality factor, Qu, averaging about 5, but the longitudinal modes may have been broa...

Nanocrystalline diamond films have attracted considerable attention because they have a low coefficient of friction and a low electron emission threshold voltage. In this paper, the author reviews the plasma-enhanced chemical vapor deposition (PE-CVD) of nanocrystalline diamond and mainly focuses on the growth of nanocrystalline diamond by low-pressure PE-CVD. Nanocrystalline diamond particles ...

Unique macrostructures known as spun carbon-nanotube fibers (CNT yarns) can be manufactured from vertically aligned forests of multiwalled carbon nanotubes (MWCNTs). These yarns behave as semiconductors with room-temperature conductivities of about 5 x 10(2) S cm(-1). Their potential use as, for example, microelectrodes in medical implants, wires in microelectronics, or lightweight conductors i...

Abstract: Mg2Ni alloy and Mg2Ni–x wt% TiO2 (x = 3, 5 and 10 wt %) composites are prepared by mechanical alloying. The produced alloy and composites are characterized as the particles with nanocrystalline/amorphous structure. The effects of TiO2 on hydrogen storage properties are investigated using anodic polarization and electrochemical impedance spectroscopy. It is demonstrated that the initia...

A low cost and scalable powder-based method for producing nanoporous Ni is demonstrated, the only processing by-product water vapor. This achieved by creating a metal–matrix composite of NiO that then reduced under dilute hydrogen to create pure with nanocrystalline structure nanoscale porosity. The technique demonstrated in loose powder thin bulk compacts centimeter dimensions. These can withs...

Nanocrystalline fluorinated silicon films are studied by using Raman spectroscopy, electron paramagnetic resonance, Fourier-transformed infrared spectroscopy, atomic force microscopy, nonlinear laser spectroscopy, and photoluminescence. Electrical properties of nanocrystalline silicon and amorphous silicon films were compared. The field-assisted migration of point defects is dramatic for durabi...

Nanocrystalline materials have experienced a great deal of attention in recent years, largely due to their impressive array of physical properties. In particular, nanocrystalline mechanical behavior has been of interest, as incredible strengths are predicted when grain size is reduced to the nanometer range. The vast majority of research to this point has focused on quantifying and understandin...

For the first time this study reported the success of using nanocrystalline hexagonal close-packed (hcp) nickel (Ni) modified composite graphite (CG) electrode (hcp-nano Ni/CG) for the electrocatalytic oxidation of glycerol in alkaline medium (0.1 M KOH). The hcp-nano Ni/CG electrode had an improve response and specificity on the electrocatalytic oxidation of glycerol over the bare CG. The elec...

          Ag-Cu solid solutions prepared via ball milling process were subsequently milled for 30 h and investigated by X-ray diffraction technique for Cu-20%Ag, Cu-3.64%Ag and Cu-80%Ag. It was noted that the solid solubility level increased by increasing initial solute content in composition. Results showed peak positions of silver and copper changed with milling time. By heating up to 700 K, ...