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Aluminum/carbon nanotube composite is a promising candidate material for aerospace applications owing to its high strength-to-weight ratio. Because of the low density of carbon nanotubes (CNTs), their dispersion is difficult in molten metal. We investigated induction melting, a fairly distinct approach to facilitate the dispersion of CNTs in molten aluminum. The nanocomposites were characterized using scanning electron microscopy, X-ray diffraction, transmission electron microscopy and mechanical testing. Refinement in crystallite size (∼320 nm) and increase in lattice strain (∼3.24 × 10 −3 ) were observed in the composites. A simultaneous increase in yield strength (∼77%), tensile strength (∼52%), ductility (∼44%) and hardness (∼45%) was observed. Induction melting appeared to be a potential method to fabricate aluminum-CNTs composites.

TiO 2 nanoparticles were synthesized at room temperature by chemical precipitation method and were then heated at 120, 300, 600 and 900 °C temperatures. The phase transition and crystallite size variation were determined by X-rays diffraction (XRD) analysis. The surface area, pore volume and pore size were measured using Brunauer-Emmet-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods. The optical activity of heat treated and non-heat treated samples were carried out by diffuse reflectance (DR) spectroscopy. Four different methods were used to calculate band gap energy. The results obtained from thermogravimetric and differential thermal gravimetric (TG/TDG) analyses and Fourier transform infra-red (FTIR) spectroscopy agreed with each other. Agar well diffusion method has been applied to explore the antibacterial activity of nanoparticles against different bacterial strains such as Bacillus subtilis, Staphylococcus Aureus, Escherichia coli and Pseudomonas Aeruginosa. It was observed that TiO 2 nanoparticles heated at 120 °C displayed maximum antibacterial activity while those heated at higher temperature showed no activity against the examined bacteria.

Using first-principles theory and further verified by the experimental results, we have studied the electronic structure, mechanical and thermal properties of La 2 B 2 O 7 (B=Zr, Sn, Hf and Ge) pyrochlore. It is shown that the La 2 B 2 O 7 pyrochlore are charge-transfer-type insulators with the strong ionic bonding. The calculated band gap of La 2 Zr 2 O 7 , La 2 Sn 2 O 7 , La 2 Hf 2 O 7 , and La 2 Ge 2 O 7 are 4.01, 3.05, 3.13 and 2.42 eV, respectively. The elastic constants, hardness, shear modulus, bulk modulus, Young's modulus and Poisson's ratio of La 2 B 2 O 7 compounds were investigated systematically. Anisotropic elastic and thermal properties of La 2 B 2 O 7 compounds were discussed by using Zener's indexes (A Z) and universal elastic anisotropic index (A U). The sound velocities along [100], [110] and [111] directions were calculated for each La 2 B 2 O 7 compounds. Both Clark's model and Cahill's model were used to evaluate the minimum thermal conductivity of all compounds. According to the Clark's model, when the temperature is much higher than Debye temperature, the minimum thermal conductivity of La