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Abstract: Anatase TiO2 nanotubes and titanate nanotubes have been successfully synthesized via hydrothermal synthesis followed by post-treatment from titanium powder. The morphology and crystalline structure of the nanotubes are characterized in detail with transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) respectively. The nanotubes have an average outer diameter of around 9–10 nm and the inner diameter around 3–4 nm with several hundred nanometers in length. A mechanism for the anatase TiO2 nanotubes transformation has also been proposed. Nanotubes are formed during the solvent thermal process, and the compositions are changed by subsequent ionic exchange and dehydration under high temperature. These tubular materials can be very useful in the fields of photocatalysts, photoelectronics and energy-storage technologies. [Copyright &y& Elsevier]

Abstract: ZrO2–Y2O3–Al2O3 nanocrystalline powders have been synthesized using chemical coprecipitation method. Nano-powders were compacted uniaxially and densified in a muffle furnace. Densification studies showed that a fully dense pellet of ZrO2(3Y) and a 99% relative density for 5 mol% Al2O3 doped ZrO2(3Y) were obtained after sintering at 1200 °C. The presence of Al2O3 inhibits grain growth and suppresses the densification process. Full densification and the maximum microhardness of 17.8 GPa were achieved for the ZrO2(3Y)/5 mol% Al2O3 composites sintered at 1250 °C. [Copyright &y& Elsevier]

Abstract: Bulk Al2O3 dispersed ultrafine-grained (UFG) Cu matrix composite has been fabricated by self-propagating high-temperature synthesis (SHS) casting route. The microstructures and mechanical properties of the as-fabricated materials have been investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, and microhardness measurements and compression tests, respectively. The results show that the as-fabricated material has small amount of entrapped Al2O3 particles in uniform microstructure Cu having a grain size ranging from 200–500 nm with an elevated compressive yield stress (298 MPa) and an improved microhardness value (1.06 GPa). The possible strengthening mechanism of the product has been discussed. [Copyright &y& Elsevier]

Abstract: Micro-and nanoscale spherical anatase TiO2 films have been successfully prepared via evaporizing–deposition route. The morphology and the crystalline structure of the samples were characterized in more detail with field emission scanning electron microscopy (FE–SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. The TiO2 films with micro-and nanoscale surface structures can be constructed by simply adjusting the evaporation condition of TiCl4 in the air after being annealed. These surfaces can be turned from super-hydrophilic to super-hydrophobic after modification with a thin layer of hydrophobic silicone, mainly depending on the surface morphology. [Copyright &y& Elsevier]