近年来,极端暴雨增加导致城市内涝愈发严重,而合理布设低影响开发(low impact development,LID)设施可以有效地缓解城市内涝问题。该文提出了一种基于溢流点位上游追踪(overflow point upstream tracking,OPUT)的LID设施布设方法。运用...近年来,极端暴雨增加导致城市内涝愈发严重,而合理布设低影响开发(low impact development,LID)设施可以有效地缓解城市内涝问题。该文提出了一种基于溢流点位上游追踪(overflow point upstream tracking,OPUT)的LID设施布设方法。运用暴雨洪水管理模型(storm water management model,SWMM)构建排水模型,模拟不同重现期管网溢流,采用OPUT方法确定需要布设LID设施的雨水子汇水区,与传统全范围等比例(traditional full range equal proportion,FREP)的LID设施布设方法结果进行对比。结果显示:从缓解内涝方面来看,OPUT方法和FREP方法节点溢流体积削减百分比在单位布设LID设施面积下均随着重现期增大而减小。从径流削减方面来看,在不同的重现期下,2种方法对径流体积和径流峰值流量的削减情况在单位布设LID设施面积下是不同的,OPUT方法对径流体积的削减在重现期较大时效果更好,对径流峰值流量的削减随着重现期的增大呈上升趋势并接近FREP方法。从经济方面来考虑,当2种方法对节点溢流的削减效果近似一致时,OPUT方法和FREP方法成本均随着重现期的增大而增加且OPUT方法的成本均小于FREP方法的。可见对于缓解内涝的LID设施布设需求,OPUT方法具有更佳的内涝缓解效果和经济性。展开更多
The active sites for hydrogenation over Ru/SBA‐15catalysts were identified using in situ Fourier‐transform infrared spectroscopy.The amount of active sites was proportional to the interfacial circumference of the Ru...The active sites for hydrogenation over Ru/SBA‐15catalysts were identified using in situ Fourier‐transform infrared spectroscopy.The amount of active sites was proportional to the interfacial circumference of the Ru particles.In contrast,the rate of hydrogen spillover from Ru to the support was inversely proportional to the size of the Ru metal particles.Consequently,a catalyst with small Ru metal particles has a high rate of hydrogen spillover but a low density of active sites,whereas one with large Ru particles has a low rate of hydrogen spillover but a high density of active sites.The formation of these active sites is probably an intermediate step in hydrogen spillover.展开更多
文摘近年来,极端暴雨增加导致城市内涝愈发严重,而合理布设低影响开发(low impact development,LID)设施可以有效地缓解城市内涝问题。该文提出了一种基于溢流点位上游追踪(overflow point upstream tracking,OPUT)的LID设施布设方法。运用暴雨洪水管理模型(storm water management model,SWMM)构建排水模型,模拟不同重现期管网溢流,采用OPUT方法确定需要布设LID设施的雨水子汇水区,与传统全范围等比例(traditional full range equal proportion,FREP)的LID设施布设方法结果进行对比。结果显示:从缓解内涝方面来看,OPUT方法和FREP方法节点溢流体积削减百分比在单位布设LID设施面积下均随着重现期增大而减小。从径流削减方面来看,在不同的重现期下,2种方法对径流体积和径流峰值流量的削减情况在单位布设LID设施面积下是不同的,OPUT方法对径流体积的削减在重现期较大时效果更好,对径流峰值流量的削减随着重现期的增大呈上升趋势并接近FREP方法。从经济方面来考虑,当2种方法对节点溢流的削减效果近似一致时,OPUT方法和FREP方法成本均随着重现期的增大而增加且OPUT方法的成本均小于FREP方法的。可见对于缓解内涝的LID设施布设需求,OPUT方法具有更佳的内涝缓解效果和经济性。
基金supported by the National Natural Science Foundation of China(21303163)the Natural Science Foundation of Zhejiang Province(LY13B030006,LY17B060006)+1 种基金the Qianjiang Talent Project in Zhejiang Province(QJD1302011)the Scientific Research Fund of Zhejiang Provincial Education Department(Y201328681)~~
文摘The active sites for hydrogenation over Ru/SBA‐15catalysts were identified using in situ Fourier‐transform infrared spectroscopy.The amount of active sites was proportional to the interfacial circumference of the Ru particles.In contrast,the rate of hydrogen spillover from Ru to the support was inversely proportional to the size of the Ru metal particles.Consequently,a catalyst with small Ru metal particles has a high rate of hydrogen spillover but a low density of active sites,whereas one with large Ru particles has a low rate of hydrogen spillover but a high density of active sites.The formation of these active sites is probably an intermediate step in hydrogen spillover.