The current wastewater treatment method shows low efficiency in treating wastewater with high concentrations of chemical mechanical pulp (CMP). Therefore, a chlorine dioxide Pretreatment Anaerobic Treatment (DPAT) was developed and applied to treat the CMP wastewater to obtain higher efficiency, obtaining the following results: The biodegradability of CMP wastewater improved after chlorine dioxide pretreatment. The COD of wastewater treated with chlorine dioxide was reduced from 5634 mg/L to 660 mg/L. The removal rate for chemical oxygen demand (COD) was 88.29%, 29.13% higher than the common anaerobic treatment. The reasons for the high efficiency of the DPAT treatment were that chlorine dioxide pretreatment removed the toxic substances in the original wastewater and thereby promoted the proliferation and growth of the anaerobe. The results show that pretreatment with chlorine dioxide can effectively enhance the biodegradability of high-concentration CMP wastewater. Therefore, DPAT treatment of high-concentration CMP wastewater is beneficial to environmental protection.

Flavonoid complexes have more biological activities than parent flavonoids, including antioxidant, anticancer, antibacterial, and many others. Selenium is an essential trace element for human body. Therefore, a quercetin-Se complex was synthesized and analyzed in this paper, getting the results as following: (1) A light-yellow product was obtained with the max yield of 30.30 %. (2) The complex molecule contains two quercetin units and a selenoxyl group, called selenious acid acyl diquercetin. (3) It has a strong antioxidant activity with a maximum DPPH scavenging rate of 97.71 %. In addition, we prepared a skin cream containing 1 % quercetin selenium complex, and it has excellent antioxidant activity with a DPPH scavenging rate of 82.4 %. Therefore, the generated selenious acid acyl diquercetin is a potential antioxidant material for skin care products.