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Different mass concentrations of Al2O3, SiO2, CuO nanofluids were made by using two-step method with the three types of base fluids deionized water, ethanol and ethylene glyco. The suspension stability of nanofluids and its effect by adding anion and cation surfactants through sedimentation method were studied. The results show that ehylene glycol is as the base fluid, the suspension stability of nanofluids with DW as the base fluid is worst. The suspension stability of Al2O3, SiO2, CuO nanofluids is significantly improved by addition of appropriate dosage of adding anion and cation surfactants for different base fluids. The effect of HTAB is better than that of SDBS.

The laser shot peening has the widely application prospect in aircraft structural parts repairment. The influence of laser shot peening parameters on the surface hardness and surface roughness has guiding significance for laser shot peening process. The variation law of surface hardness and surface roughness in the peening area of 7075 aluminum alloy were obtained based on the experiment research. The results show that the surface hardness improves effectively after laser shot peening, and the maximum hardness is 205.4HV, which is improved by 19.49% compared with the original hardness. Besides, the surface roughness of the rough specimen decreases; whereas, those of the smooth specimen increases after laser shot peening. However, both the surface hardness and surface roughness tend to be saturated when the impact times exceeds 3 times or the overlap rate exceeds 50%. Therefore, a good repairment effect can be obtained with 3 impact times and 50% overlap rate for the 7075 aluminum alloy specimen.

Hierarchical bis(8-hydroxyquinoline) nickel(NiQ2) complex has been synthesized with a facile method in a mixed solvent system at 120 °C for 12 h. The molecular formula of the products is speculated by the C, H and N element analysis and thermal gravimetric analysis, and Fourier-transformation infrared spectroscopy was also utilized to measure its structure, which further confirm the molecular formula of the products. The observation of field emission scanning electron microscopy shows that the morphology of bis(8-hydroxyquinoline) nickel complex is flower-like structure. According to the result, it is found that the photoluminescence of bis(8-hydroxyquinoline) nickel complex is stronger than that of 8-hydroxyquinoline, which indicate that inorganic elements played key roles in their luminescence properties.

Tris(8-hydroxyquinoline) bismuth complex has been synthesized with a facile method in a mixed solvent system containing bismuth nitrate and 8-hydroxyquinolineat at room temperature. The molecular formula of the products is speculated by the C, H and N element analysis and thermal gravimetric analysis, and FTIR was also utilized to measure the structure, which further confirms the molecular formula of the products. The observation of FESEM and TEM shows that the morphology of tris(8-hydroxyquinoline) bismuth complexes is rod-like structure. The results of photoluminescence emission indicate that inorganic element plays key roles in the luminescence property. According to the results, we found that the photoluminescence of tris-(8-hydroxyquinoline) bismuth is stronger than that of 8-hydroxyquinoline.