Strain HG-7 was identified as Pseudomonas sp. through 16s rRNA gene sequence analysis. The aerobic denitrification ability of strain HG-7 was further proved by the existence of the napA and nirK genes. Further studies showed that the optimal carbon resources for strain HG-7 were sodium acetate and sodium succinate, the optimal C/N ratio was 6−10, and the suitable temperature was 26−30℃. At this condition, with an initial nitrate nitrogen of 100 mg/L, 98% of nitrate could be removed in 48 hours and the amount of nitrite accumulation was very small. Moreover, with nitrite as the sole nitrogen source, 100% of nitrite could be removed at lower nitrite concentration. But the nitrite nitrogen removal rate was about 40% when the nitrite concentration increased to 91.4 mg/L, indicating that high nitrite concentration was harmful for aerobic denitrification by strain HG-7. The strain HG-7 has great potential to be used for biological nitrogen removal, which was particularly significant for actual wastewater treatment processes.

The author derives the relationship between incidence angle and offset in the model where the overlaying layer is homogeneous and isotropic medium while the under-cladding layer is anisotropic. Based on the reflection coefficient expressions in Horizontal Transversely Isotropic medium (HTI medium) proposed by Ruger, and inverses the elastic parameters of layers. By comparing the results with other previous methods, it verifies the correctness of the new method and the superiority of the algorithm.

Star-shaped dendritic PbS nanocrystals have been synthesized by the reaction of lead acetate and thioacetamide in the presence of CTAB through a hydrothermal process at 80 ℃ for 5 h. XRD, TEM, SAED, SEM were used to characterize the products. The results show that the products were star-shaped dendritic PbS single crystals in cubic phase, and the six arms of the star extended along the six <100> directions. It has been found that the presence of the CTAB and the release rate of S^2- ions from the sulfur sources are crucial for the formation of the star-shaped dendritic PbS crystals.