In the Wenchuan Earthquake area,many co-seismic landslides formed blocking-dams in debris flow channels. This blocking and bursting of landslide dams amplifies the debris flow scale and results in severe catastrophes....In the Wenchuan Earthquake area,many co-seismic landslides formed blocking-dams in debris flow channels. This blocking and bursting of landslide dams amplifies the debris flow scale and results in severe catastrophes. The catastrophic debris flow that occurred in Qipan gully(Wenchuan,Southwest China) on July 11,2013 was caused by intense rainfall and upstream cascading bursting of landslide dams. To gain an understanding of the processes of dam bursting and subsequent debris flow scale amplification effect,we attempted to estimate the bursting debris flow peak discharges along the main gully and analyzed the scale amplification process. The results showed that the antecedent and triggering rainfalls for 11 July debris flow event were 88.0 mm and 21.6 mm,respectively. The event highlights the fact that lower rainfall intensity can trigger debris flows after the earthquake. Calculations of the debris flow peak discharge showed that the peak discharges after the dams-bursting were 1.17–1.69 times greater than the upstream peak discharge. The peak discharge at the gully outlet reached 2553 m^3/s which was amplified by 4.76 times in comparison with the initial peak discharge in the upstream. To mitigate debris flow disasters,a new drainage channel with a trapezoidal V-shaped cross section was proposed. The characteristic lengths(h1 and h2) under optimal hydraulic conditions were calculated as 4.50 m and 0.90 m,respectively.展开更多
Economy globalization inevitably requires financial globalization. The interest rate （IR） is decided by the market, which will bring about IR risks to commercial banks （CBs）. This paper discusses the inevitability...Economy globalization inevitably requires financial globalization. The interest rate （IR） is decided by the market, which will bring about IR risks to commercial banks （CBs）. This paper discusses the inevitability of fulfilling market IR in China and what IR risks Chinese CBs have to burden. It also analyzes the formation causes of IR risks from the exterior and the interior aspects.展开更多
The comprehensive control efficiency for the formation potentials（FPs） of a range of regulated and unregulated halogenated disinfection by-products（DBPs）（including carbonaceous DBPs（C-DBPs）, nitrogenous DBPs（N...The comprehensive control efficiency for the formation potentials（FPs） of a range of regulated and unregulated halogenated disinfection by-products（DBPs）（including carbonaceous DBPs（C-DBPs）, nitrogenous DBPs（N-DBPs）, and iodinated DBPs（I-DBPs）） with the multiple drinking water treatment processes, including pre-ozonation, conventional treatment（coagulation–sedimentation, pre-sand filtration）, ozone-biological activated carbon（O_3-BAC） advanced treatment, and post-sand filtration, was investigated. The potential toxic risks of DBPs by combing their FPs and toxicity values were also evaluated.The results showed that the multiple drinking water treatment processes had superior performance in removing organic/inorganic precursors and reducing the formation of a range of halogenated DBPs. Therein, ozonation significantly removed bromide and iodide,and thus reduced the formation of brominated and iodinated DBPs. The removal of organic carbon and nitrogen precursors by the conventional treatment processes was substantially improved by O_3-BAC advanced treatment, and thus prevented the formation of chlorinated C-DBPs and N-DBPs. However, BAC filtration leads to the increased formation of brominated C-DBPs and N-DBPs due to the increase of bromide/DOC and bromide/DON.After the whole multiple treatment processes, the rank order for integrated toxic risk values caused by these halogenated DBPs was haloacetonitriles（HANs）》haloacetamides（HAMs） 〉haloacetic acids（HAAs） 〉 trihalomethanes（THMs） 〉 halonitromethanes（HNMs） 》I-DBPs（I-HAMs and I-THMs）. I-DBPs failed to cause high integrated toxic risk because of their very low FPs. The significant higher integrated toxic risk value caused by HANs than other halogenated DBPs cannot be ignored.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant No.41572302)the Funds for Creative Research Groups of China (Grant No.41521002)
文摘In the Wenchuan Earthquake area,many co-seismic landslides formed blocking-dams in debris flow channels. This blocking and bursting of landslide dams amplifies the debris flow scale and results in severe catastrophes. The catastrophic debris flow that occurred in Qipan gully(Wenchuan,Southwest China) on July 11,2013 was caused by intense rainfall and upstream cascading bursting of landslide dams. To gain an understanding of the processes of dam bursting and subsequent debris flow scale amplification effect,we attempted to estimate the bursting debris flow peak discharges along the main gully and analyzed the scale amplification process. The results showed that the antecedent and triggering rainfalls for 11 July debris flow event were 88.0 mm and 21.6 mm,respectively. The event highlights the fact that lower rainfall intensity can trigger debris flows after the earthquake. Calculations of the debris flow peak discharge showed that the peak discharges after the dams-bursting were 1.17–1.69 times greater than the upstream peak discharge. The peak discharge at the gully outlet reached 2553 m^3/s which was amplified by 4.76 times in comparison with the initial peak discharge in the upstream. To mitigate debris flow disasters,a new drainage channel with a trapezoidal V-shaped cross section was proposed. The characteristic lengths(h1 and h2) under optimal hydraulic conditions were calculated as 4.50 m and 0.90 m,respectively.
文摘Economy globalization inevitably requires financial globalization. The interest rate （IR） is decided by the market, which will bring about IR risks to commercial banks （CBs）. This paper discusses the inevitability of fulfilling market IR in China and what IR risks Chinese CBs have to burden. It also analyzes the formation causes of IR risks from the exterior and the interior aspects.
基金supported by the National Major Science and Technology Project of China (No.2015ZX07406-004)
文摘The comprehensive control efficiency for the formation potentials（FPs） of a range of regulated and unregulated halogenated disinfection by-products（DBPs）（including carbonaceous DBPs（C-DBPs）, nitrogenous DBPs（N-DBPs）, and iodinated DBPs（I-DBPs）） with the multiple drinking water treatment processes, including pre-ozonation, conventional treatment（coagulation–sedimentation, pre-sand filtration）, ozone-biological activated carbon（O_3-BAC） advanced treatment, and post-sand filtration, was investigated. The potential toxic risks of DBPs by combing their FPs and toxicity values were also evaluated.The results showed that the multiple drinking water treatment processes had superior performance in removing organic/inorganic precursors and reducing the formation of a range of halogenated DBPs. Therein, ozonation significantly removed bromide and iodide,and thus reduced the formation of brominated and iodinated DBPs. The removal of organic carbon and nitrogen precursors by the conventional treatment processes was substantially improved by O_3-BAC advanced treatment, and thus prevented the formation of chlorinated C-DBPs and N-DBPs. However, BAC filtration leads to the increased formation of brominated C-DBPs and N-DBPs due to the increase of bromide/DOC and bromide/DON.After the whole multiple treatment processes, the rank order for integrated toxic risk values caused by these halogenated DBPs was haloacetonitriles（HANs）》haloacetamides（HAMs） 〉haloacetic acids（HAAs） 〉 trihalomethanes（THMs） 〉 halonitromethanes（HNMs） 》I-DBPs（I-HAMs and I-THMs）. I-DBPs failed to cause high integrated toxic risk because of their very low FPs. The significant higher integrated toxic risk value caused by HANs than other halogenated DBPs cannot be ignored.
