In order to explore the best extraction technology of flavonoids from Maoyanberry tea, the extraction conditions of flavonoids from Maoyanberry tea were optimized by using the method of single factor and response surface. The results showed that the optimal extraction conditions were as follows: Ethanol volume fraction 80%, liquid?solid ratio 25 mL/g, water bath temperature 85 ℃, water bath time 40 min. Under these conditions, the yield of flavonoids was 162.72 mg/g, which was close to the predicted value of the model, indicating that the optimized method was reasonable and feasible.

The Bi2Sr2CaCu2O8+δ(Bi-2212) superconducting powders were synthesized by Pechini method. The samples were prepared with metal nitrates as starting materials, ethylene diamine tetracetic acid (EDTA) as chelating agent and ethylene glycol as cross-linking agent. The effect of EDTA amount, ethylene glycol amount, oil bath temperature and time during gel processes on the crystallnity and superconductivity of Bi-2212 powders were investigated. The X-ray diffraction (XRD) was employed to investigate the phase purity and crystallnity. The resistance measurements were carried out with a conventional four-probe method. The results showed that phase purity is slightly affected by different gel processes. But the crystallnity and electrical conductivity of Bi-2212 phase changes obviously as shown by the XRD patterns and R-T curves. The difference of its critical transition temperature Tc,0 is 7.3 K.