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Abstract: Multi-walled carbon nanotube (MWNT) reinforced carbon matrix (MWNT/C) composites have been explored using mesophase pitch as carbon matrix precursor in the present work. Results show that carbon nanotubes (CNTs)can enhance the mechanical properties of carbon matrix significantly. The maximal increment of the bending strength and stiffness of the composites, compared with the carbon matrix, are 147% and 400%, respectively. Whereas the highest in-plane thermal conductivity of the composites is 86 W m−1 K−1 which much lower than that of carbon matrix (253 W m−1 K−1).At the same time the electrical resistivity of the composites is much higher than that of matrix. It is implicated that CNTs seem to play the role of thermal/electrical barrier in the composites. FSEM micrograph of the fracture surface for the composites shows that the presence of CNTs restrains the crystallite growth of carbon matrix, which is one of factors that improve mechanical properties and decrease the conductive properties of the composites. The defects and curved shape of CNTs are also the affecting factors on the conductive properties of the composites. [Copyright &y& Elsevier]

Abstract: WO3·0.33H2O nanoplates have been synthesized with p-nitrobenzoic acid as a structure-directing agent through a facile hydrothermal method. The obtained products were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The SEM results showed that most of the products had a hexagonal morphology with a lateral size of 500–1000nm and a thickness of ∼80nm. The XRD result showed that the products were orthorhombic WO3·0.33H2O. The photocatalytic and gas-sensing properties of the WO3·0.33H2O nanoplates were studied. The products exhibited a high degradation activity for methylene blue (MB) under ultraviolet light irradiation, and a high sensitivity to cyclohexene. The facile preparation method and the improved properties derived from the plate-shaped nanostructures are significant in the synthesis and future applications of functional nanomaterials. [Copyright &y& Elsevier]