2008 DEC 29 - (VerticalNews.com) -- "Nanocrystalline Y2O3 powders with 18 nm crystallite size were sintered using spark plasma sintering (SPS) at different conditions between 1100 and 1600 degrees C. Dense specimens were fabricated at 100 MPa and 1400 degrees C for 5 min duration. A maximum in density was observed at 1400 degrees C. The grain size continuously increased with the SPS temperature into the micrometer size range," scientists writing in the Journal of the European Ceramic Society report ...read more

  2008 DEC 29 - (VerticalNews.com) -- According to recent research from Crawley, Australia, "In this study, mechanochemical reaction systems with H2WO4 as a precursor were investigated for the synthesis of nanoparticulate powders of WO3, ZnWO4, and dual-phase (ZnWO4)(x)(ZnO)(1-x). The objective was to establish whether mechanochemical processing can be used to manufacture high activity photocatalysts in the ZnO-WO3 system."

  "Milling and heat treatment of H2WO4 + 12NaCl was found to result in the formation of irregularly shaped platelets of a sodium tungstate rather than nanoparticles Of WO3. Powders of single-phase ZnWO4 and dual-phase (ZnWO4)(x)(ZnO)(1-x) were successfully synthesised by incorporating H2WO4 into the ZnCl2 + Na2CO3 + 4NaCl reactant mixture. The photocatalytic activity of these powders was evaluated using the spin-trapping technique with electron paramagnetic resonance spectroscopy. It was found that the photocatalytic activity decreased with the ZnWO4 content," wrote A. Dodd and colleagues, University of Western Australia ...read more

  2008 DEC 29 - (VerticalNews.com) -- According to recent research published in the Journal of the European Ceramic Society, "Hexagonal aluminum nitride (AlN) nanowires were fabricated by direct sublimation method without a catalyst layer. The obtained nanowires have diameters of about 30-100 nm and length up to tens of micrometers."

  "TEM observation indicates that these nanowires are single-crystalline and grow along [0 0 0 1] direction. It is thought that vapor-solid (VS) mechanism should be responsible for the growth of AlN nanowires. In addition, room temperature Raman scattering and photoluminescence spectra from AlN nanowires were studied," wrote M. Lei and colleagues, Technical University ...read more