In order to improve the high temperature oxidation and ablation resistance of C/C composites, ZrB2-ZrC-SiC ultra-high temperature composite ceramic coatings were prepared on C/C composites by laser cladding using Zr, B4C, and Si as raw materials. The microstructure of the coating was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Air isothermal oxidation (1600 °C, 80 min) and oxyacetylene flame ablation (2400 kW/m2, 300 s) were used to evaluate the high-temperature oxidation and ablation properties of the coating, respectively. The results show that the microstructure of laser cladding coating is a totem of black and white. The white part is mainly the first solidified high melting point ZrB2 phase, and the black part is the latter solidified eutectic structure, which is mainly composed of ZrB2(ZrB12)-ZrC or ZrB2(ZrB12)-SiC two phases. After oxidation at 1600 °C and 80 min, the coating is mainly composed of ZrO2 and ZrSiO4 phases, and ZrSiO4 is basically distributed among ZrO2 particles. The high temperature oxidation and ablation properties of the coating are better than the C/C composite matrix, and the mass ablation rate of the coating is about 1/4 of the latter.

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A tubular desalination still is designed with surface modification by hydrophilic and wrapped absorbent material. This paper discusses the mechanism of heat and mass transfer inside the modified system, carries out the experiments of constant temperature and constant power heating, and the water yield of the tubular desalination still before and after surface hydrophilic / water absorption modification is obtained. The experimental results show that, water yield rate of the still is linearly proportional to the operation temperature. The water yield rate of the modification tubular still is up to 297 ml•h -1 when temperature is 85 °C, almost 25 % higher than that of the smooth tube. When the constant power (150 W) is used to heat for 12 h, the total water yield and the Performance Ratio of the modification tubular still are 2057.7 ml and 0.72, respectively, improved by 30.9 % when compared with that of the smooth tube.