具有循环净化性能的纳米TiO_2/活性炭复合表面的构筑

目的构筑净化性能优异的纳米TiO_2/活性炭复合表面。方法采用溶凝胶模板法构筑球形表面,将乳化法制备的石蜡球和复合活性炭的纳米TiO_2溶胶挤压成形,温和处理后形成规则稳定的球形表面。使用SEM、XRD和FTIR进行表面微观结构、形貌和物相检测,采用X射线断层扫描对球形表面结构进行重构和球面特征分析。分析测定了不同当量直径球形表面的样品对亚甲基蓝的净化效果。结果温和处理工艺维持了原始P25粉末的晶型和晶粒尺寸,溶凝胶模板法可以形成贯通、多面、多孔径的结构和簇状均匀表面。3DCT结果显示,活性炭的复合使样品形成了碳增强的TiO_2球形表面。构筑成功的纳米TiO_2复合活性炭样品,在8个周期的循环吸附-净化中可以完全将亚甲基蓝净化降解。平均当量直径为0.67mm的样品,在9个周期的净化反应中,净化率可以保持100%。结论溶凝胶模板法成功构筑了纳米TiO_2复合活性炭的球形连续表面,球形表面之间大的孔道连接和活性炭在纳米TiO_2颗粒之间的复合,可以提高传质效率,从而提高循环净化性能

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^