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二元地基基坑抽水试验及数值分析 被引量:2
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作者 段衍伟 李守德 王保田 《水利与建筑工程学报》 2014年第1期125-129,共5页
秦淮河船闸地基土呈典型的二元结构地基形式,由于地质勘察阶段试验井位置选取、已有渗流通道以及影响半径取值等影响因素的存在使得地质勘查阶段渗透系数的计算值与以往的工程实践经验数值差距较大,为了更加准确的描述现场的水文地质条... 秦淮河船闸地基土呈典型的二元结构地基形式,由于地质勘察阶段试验井位置选取、已有渗流通道以及影响半径取值等影响因素的存在使得地质勘查阶段渗透系数的计算值与以往的工程实践经验数值差距较大,为了更加准确的描述现场的水文地质条件,为工程降水设计、施工提供准确的水文地质参数,利用抽水试验得到的数据,对现场的地基土建立空间轴对称模型,根据建立的地基土层观测井模型以及远端孔压计所测得的水位对模型扩大分析,反算了地基土的渗透系数,一定程度上降低了影响半径以及经验公式中假设带来的一些误差以及现场基坑范围内管涌通道的影响,通过对比得到地基土的渗透系数都小于地质勘察阶段所得到的渗透系数更加接近工程实践经验数值,对基坑的涌水量进行了更加准确的定量,对工程实践有一定的指导意义。 展开更多
关键词 基坑降水 抽水试验 数值模拟 渗透系数
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基于能量守恒原理滑石板岩质边坡滑坡速度分析
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作者 郝晓平 段衍伟 唐博 《科技和产业》 2021年第1期175-178,共4页
针对云南省金沙江两家人水电站滑石板边坡拉裂区岩体,考虑滑坡体下滑过程中与坡下已有堆积体发生冲击碰撞的作用,基于能量守恒的原理,依据滑坡体锁固段储能方式的不同,计算了滑坡遽发时的速度,并且依次分析了滑坡下滑各阶段速度和加速... 针对云南省金沙江两家人水电站滑石板边坡拉裂区岩体,考虑滑坡体下滑过程中与坡下已有堆积体发生冲击碰撞的作用,基于能量守恒的原理,依据滑坡体锁固段储能方式的不同,计算了滑坡遽发时的速度,并且依次分析了滑坡下滑各阶段速度和加速度的变化,得出了滑坡体下滑的最终速度;考虑到初始启滑速度及其与坡下堆积体的冲击碰撞作用在预测滑坡的速度及堆积规模方面不可忽略,可为其他滑坡速度的预测和滑坡后减灾防灾综合分析提供参考。 展开更多
关键词 滑坡参数 滑坡速度 冲击碰撞 堆积规模
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Chemical constituents isolated from the aerial parts of Swertia pseudochinensis and their potential neuroprotective effects 被引量:2
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作者 Ke Xiang Qi He +4 位作者 Yanmei Chen Dongxin Yang Yanwei Duan Hua Li Lixia Chen 《Acupuncture and Herbal Medicine》 2021年第1期59-64,共6页
Objective:Swertia pseudochinensis,an annual herb of the genus Swertia in the family Gentianaceae.Some constituents and extracts from the Swertia genus have been recently reported to possess neuroprotective effects,sug... Objective:Swertia pseudochinensis,an annual herb of the genus Swertia in the family Gentianaceae.Some constituents and extracts from the Swertia genus have been recently reported to possess neuroprotective effects,suggesting their potential utility in the prevention and treatment of Parkinson disease(PD).The aim of this work is to identify the chemical constituents and evaluate the potential biological activists of Swertia pseudochinensis.Methods:The phytochemicals from the aerial parts of S.pseudochinensis were isolated and purified by silica gel,Sephadex LH-20 gel,semi-preparative high-performance liquid chromatography,and identified by the spectroscopic methods.All compounds were evaluated for their potential neuroprotective effects against 1-methyl-4-phenylpyridinium-induced apoptosis in the SH-SY5Y human neuroblastoma cell line using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay.Then,we performed an enrichment analysis using the Database for Annotation,Visualization,and Integrated Discovery and investigated the mechanisms by which bellidifolin regulates neurodegenerative disease.Results:Two new anthraquinone,1,5,6-trimethoxy-2-hydroxy-3-methy-anthraquinone(1)and 1,5,6,8-tetramethoxy-2-hydroxy-3-methyanthraquinone(2),together with nine known including 7-O-b-d-glucopyranosyl-1,8-dihydroxy-3-methoxyxanthone(3),gentisin(4),swertianolin(5),bellidifolin(6),gentiacaulein(7),norswertianolin(8),5-O-b-d-glucopyranosyl-1,3,8-trihydroxyapatone(9),1-hydroxy-3,5,8-trimethoxyxanthone(10),and aurantio-obtusin(11),were isolated and compounds 6–8 and 10 exhibited neuroprotective effects at a concentration of 50mmol/L.Among them,bellidifolin showed significant protective activity,and might have potential as a neuroprotective agent for the treatment of PD,possibly by acting on oxidative damage and reactive oxygen species.Conclusions:These findings indicate that further research on the genus Swertia and its bioactive constituents toward neurodegenerative disorders could be extremely rewarding. 展开更多
关键词 ANTHRAQUINONE Neuroprotective effect Parkinson disease Swertia pseudochinensis XANTHONE
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