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西南喀斯特区不同土地利用梯田优先流定量分析
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作者 司琴 余佳峻 +3 位作者 高泽超 张帅普 付智勇 徐勤学 《中国农村水利水电》 北大核心 2023年第8期191-197,共7页
为探明不同土地利用类型条件下优先流入渗的定量特征,以西南喀斯特地区梯田的园地、耕地和林地为研究对象,通过表置式环式入渗仪和亮蓝进行染色入渗试验,对梯田上不同土地利用类型的优先流和基质流进行了定量划分,并对其入渗速率和累积... 为探明不同土地利用类型条件下优先流入渗的定量特征,以西南喀斯特地区梯田的园地、耕地和林地为研究对象,通过表置式环式入渗仪和亮蓝进行染色入渗试验,对梯田上不同土地利用类型的优先流和基质流进行了定量划分,并对其入渗速率和累积入渗量进行了对比研究。结果表明:①基质流是该地区梯田土壤入渗的主要部分。②在整个入渗过程中,园地和耕地的优先流渗透率都大于林地,达到稳定入渗时,耕地和园地的优先流入渗率分别是林地的1.87和1.80倍,累积入渗量是林地的1.2和1.3倍。③从染色渗透深度来看,耕地的优先流运动深度可达32.1 cm,明显大于园地(25.5 cm)和林地(15.7 cm),即与林地相比,园地和耕地具有更好的孔隙发育,优先流现象更明显。④不同土地利用方式的土壤质地显著影响优先流入渗率和入渗量的大小。研究结果可深化对西南喀斯特梯田入渗过程的认识,并对防控西南喀斯特地区水土流失具有一定指导意义。 展开更多
关键词 西南喀斯特区 梯田 土地利用类型 优先流 入渗
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Flood risk assessment of check dams in the Wangmaogou watershed on the Loess Plateau of China
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作者 gao ze-chao SHI Peng +4 位作者 LI Zhan-bin LI Peng BAI Lu-lu JIA Yi-li CUI Lin-zhou 《Journal of Mountain Science》 SCIE CSCD 2023年第12期3631-3647,共17页
Check dams have been widely used in China’s Loess Plateau region due to their effectiveness in erosion and flood control.However,the safety and stability of the check dam decrease with the operation process,which inc... Check dams have been widely used in China’s Loess Plateau region due to their effectiveness in erosion and flood control.However,the safety and stability of the check dam decrease with the operation process,which increases the probability of dam failure during flood events and threatens local residents’ life and property.Thus,this study simulated flood process of the check dam failure in the Wangmaogou watershed in Yulin City,Shaanxi Province,China,calculated different types of inundation losses based on the flood inundation area within the watershed,and determined the number of key flood protection check dams by classifying the flood risk levels of the check dams.The results showed that 5 dams in the watershed were subject to overtopping during different rainfall return periods,which was related to their flood discharge capacity.Dam failure flood process showed a rapid growth trend followed by slow decrease,and the time of flood peak advanced with increase in the return period.After harmonization of evaluation scales,the magnitude of flood inundation losses can be ranked as:economic losses(212.409 million yuan) > life losses(10.368 million yuan) > ecological losses(6.433 million yuan).The risk value for both individual dams and the whole dam system decreases as the return period increases.The number of key flood protection check dams in the Wangmaogou watershed was 2,3,3,3,4,and 5 for floods with return periods of 10,20,30,50,100,and 200 years,respectively.The results provided a theoretical basis for the safe operation and risk evaluation of check dams in the Loess Plateau Hills watershed. 展开更多
关键词 Check dam Return period Flood control risk Dam failure Inundation loss
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2m级SiC轻量化主镜的边缘切向剪切支撑设计与优化 被引量:4
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作者 高则超 王富国 +2 位作者 丁良 魏梦琦 王瑞 《科学技术与工程》 北大核心 2018年第27期130-134,共5页
基于2m口径望远镜工程化应用的需求,在轴向支撑采用18点Whiffletree结构的基础上,展开对大口径侧向支撑方案的设计与优化,达到理想支撑效果的目的。针对一个直径2030 mm的轻量化主镜,采用12个边缘离散支撑点;运用侧向均匀承重支撑思想... 基于2m口径望远镜工程化应用的需求,在轴向支撑采用18点Whiffletree结构的基础上,展开对大口径侧向支撑方案的设计与优化,达到理想支撑效果的目的。针对一个直径2030 mm的轻量化主镜,采用12个边缘离散支撑点;运用侧向均匀承重支撑思想选择支撑点的位置;引用修正的边缘切向剪切支撑公式优化支撑力的角度;并进行敏感性分析。结果表明:镜面变形为23.15nm;系统一阶模态为12.6Hz。可见该设计方案满足2m级SiC轻量化主镜的支撑要求。 展开更多
关键词 侧向支撑 均匀承重 边缘切向剪切 轻量化主镜
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