Lotus (Nelumbo nucifera) leaves, a traditional Chinese medicinal herb, are rich in flavonoids.In an effort to thoroughly analyze their flavonoid components, macroporous resin chromatography coupled with HPLC-MS/MS was employed to simultaneously enrich and identify flavonoids from lotus leaves. Flavonoids extracted from lotus leaves were selectively enriched in the macroporous resin column, eluted subsequently as fraction II, and successively subjected to analysis with the HPLC-MS/MS and bioactivity assays. Altogether, fourteen flavonoids were identified, four of which were identified from lotus leaves for the first time, including quercetin 3-O-rhamnopyranosyl-(1→2)-glucopyranoside, quercetin 3-O-arabinoside, diosmetin 7-O-hexose, and isorhamnetin 3-O-arabinopyranosyl-(1→2)-glucopyranoside. Further bioactivity assays revealed that these flavonoids from lotus leaves possess strong antioxidant activity, and demonstrate very good potential to be explored as food supplements or even pharmaceutical products to improve human health.

The valve is an important control unit in all kinds of fluid conveying system, which has formed a series product. The design of the valve product follows the characteristic process, and there is a strong correlation between its components. Using knowledge engineering related theory and method, through mining and presentation about the field design knowledge and structure knowledge of the pressure valve, implements the pressure valve parametric variant design templates by using the top-down design and parametric design technology on the NX platform. It can greatly improve the design efficiency and quality through the rapid variant design of series of the valve with the template.