Nanotechnology

  2010 APR 26 - (VerticalNews.com) -- "In this work, the electrogravimetric behavior of copper electrodeposition on TiO2 electrodes was analyzed. Copper electrodeposition was carried out in 0.1 mol L-1 H2SO4 using several concentrations of CuSO4," scientists in Sao Carlos, Brazil report.

  "The voltammetric curve displays a redox processes. The first redox process occurs in the region of -0.30 at 0.1 V (vs. saturated calomel electrode, SCE) and it is related to bulk Cu electrodeposition and stripping. For this cathodic process, it was observed that the mass gain increases both as the sweep rate decreases and as the concentration of copper increases. The second redox process, which occurs between -0.1 V and 0.35 V (vs. SCE), the stripping charge (and mass) are independent of both sweep rate and CuSO4 concentration and, finally, there is a saturation charge (and saturation mass) as the deposition time is increased," wrote A.V. Rosario and colleagues ...read more

  2010 APR 26 - (VerticalNews.com) -- "Nanocrystalline films were directly prepared by spray deposition of a preformed polyol-based Ni0.8Zn0.2Fe2O4 sol on a moderately heated glass substrate. The microstructural and magnetic properties of these films are investigated by X-ray diffraction, scanning electron microscopy and magnetic measurements on a Super Quanducting Interference Devices magnetometer," investigators in Paris, France report ...read more

  2010 APR 26 - (VerticalNews.com) -- According to recent research from Sherbrooke, Canada, "We report on the effect of thermal annealing on the structural and mechanical properties of amorphous SiC thin films prepared by means of a polymer-source chemical vapor deposition process. The chemical bondings of the a-SiC:H films were systematically examined by means of Fourier transform infrared spectroscopy (FTIR)."

  "The film composition was measured by X-ray photoelectron spectroscopy, while X-ray reflectivity measurements were used to account for the film density variations caused by the post-annealing treatments over the 750-1200 degrees C range. In addition, their mechanical properties (hardness and Young's modulus) were investigated by using the nano-indentation technique. FTIR measurements revealed that not only the intensity of a-SIC absorption band linearly increases but also its position is found to shift to a higher wave number as a result of annealing. In addition, the bond density of Si C is found to increase from (101.6-224.5) x 10(21) bond center dot cm(-3) accompanied by a decrease of Si-H bond density from (2.58-0.46)x10(21) bond center dot cm(-3) as a result of increasing the annealing temperature (L) from 750 to 1200 degrees C. Annealing-induced film densification is confirmed, as the a-SIC film density is found to increase from 236 to similar to 2.75 g/cm(-3) when L is raised from 750 to 1200 degrees C. In addition, as T-a is increased from 750 to 1200 degrees C, both hardness and Young's modulus are found to increase from 15.5 to 17.6 GPa and 155 to 178 GPa, respectively," wrote Y. Awad and colleagues ...read more