Absorption capability of chestnut shells for copper removal from aqueous solution

研究食品加工剩余物板栗壳对水中Cu2+的吸附性能,为其用于含铜废水的处理提供理论依据。【方法】研究吸附质溶液pH、Cu2+质量浓度、吸附剂用量、粒径、吸附温度和时间对板栗壳吸附Cu2+效果的影响,探讨吸剂和吸附剂循环利用次数对解吸和再生的影响;并采用穿透曲线和洗脱曲线对动态吸附进行了分析。【结果】吸附质溶液pH值为6、Cu2+起始质量浓度为20 mg/L、吸附剂粒径为0.25 mm时的吸附效果较好,该吸附为放热过程,升高温度虽然可以加快吸附进程,但却降低了吸附量和去除率。Na+和Ca2+对Cu2+的解吸置换能力较弱,0.1mol/L HCl可使96.1%的Cu2+得以解吸回收。通过Thomas模型预测,在固定床柱吸附条件下饱和吸附量为10.94mg/g。【结论】板栗壳对水中Cu2+的吸附性能较好,因而具有很好的应用前景

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies