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In this paper, carbon materials with solid and hollow sphere morphologies, have been prepared by reduction of hexachlorobenzene with metallic sodium at temperatures of 400-500°C for 6-10h. Characterized by XRD, TEM, SAED and Raman spectrum, the composition and morphology of the products are confirmed. The possible formation mechanism has also been proposed.

The theoretical model of the solidification process of a shell-and-tube ice storage (STIS) device with longitudinal fins is established. The liquid fraction, the energy-discharging rate and the ice storage ratio are investigated, with particular focus on the effects of the fin structure parameters on the solidification process. Furthermore, the temperature and the streamline distributions are discussed to reveal the mechanism of the solidification process in the STIS device and the negative effect of natural convection (NC). It is indicated that the solidification process of the STIS device is dominated by the heat transfer via the fins at the beginning, and then by the heat transfer at the water-ice interface. The ice storage is negatively affected by the NC, for the reason that the water with a higher temperature stays in the lower part of the STIS device and the temperature gradient at the water-ice interface is small. The ice storage performance can be enhanced by increasing the fin structure parameters, including height, thickness and number.

Nanocrystalline CuO with shuttle-morphology has been prepared conventionally by a microwave irradiation heating technique from an aqueous system in the presence of Cu(CH3COO)2• H2O and NaOH at room temperature. The X-ray powder diffraction pattern indicates that the product is indicated that the product was pure monoclinic phase of CuO. Further characterized by transmission electron microscopy, selected area electron diffraction, X-ray photoelectron spectroscopy and Raman spectra, the component of the products were confirmed.