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花岗岩地区铁路深大竖井治水案例及治水效率分析
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作者 王唤龙 刘建兵 +1 位作者 杨昌宇 朱廷宇 《隧道建设(中英文)》 CSCD 北大核心 2021年第3期402-410,共9页
为研究铁路隧道竖井建井期间主要治水方案定量化选择的科学依据,从竖井建井方案定性选择的特点入手,依据高黎贡山隧道在火成岩地区竖井注浆堵水的实践,结合2个竖井建井期间2次地面预注浆、42次工作面注浆和47次壁后注浆的实测数据,统计... 为研究铁路隧道竖井建井期间主要治水方案定量化选择的科学依据,从竖井建井方案定性选择的特点入手,依据高黎贡山隧道在火成岩地区竖井注浆堵水的实践,结合2个竖井建井期间2次地面预注浆、42次工作面注浆和47次壁后注浆的实测数据,统计注浆堵水后井筒内的剩余漏水量,计算3种注浆措施后的堵水率。基于数据挖掘和决策方法,分析计算单一或多种堵水措施实施后的堵水率数学期望,提出一种满足数学期望的花岗岩地区竖井堵水定量化评价指标。计算结果表明,采用多种注浆方式组合的综合方案较单一注浆方案处理竖井涌水量的能力提高12~15倍。建议花岗岩地区竖井建井前或掘砌前应采取系统化的堵水措施,保证建井安全,改善井内施工环境。 展开更多
关键词 铁路隧道 竖井 堵水方案 治水效率 注浆
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Research on Anti-bacterial Effects of 5 Kinds of Chinese Herb Extracts on Ameromonas hydrophila in vitro 被引量:8
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作者 姜巨峰 王玉佩 李春艳 《Agricultural Science & Technology》 CAS 2010年第8期145-148,共4页
[Objective] The aim was to study the anti-bacterial effects of 5 kinds of Chinese herb extracts on Ameromonas hydrophila in vitro. [Method] in vitro anti-bacterial effects of 5 kinds of Chinese herb extracts like Gall... [Objective] The aim was to study the anti-bacterial effects of 5 kinds of Chinese herb extracts on Ameromonas hydrophila in vitro. [Method] in vitro anti-bacterial effects of 5 kinds of Chinese herb extracts like Galla Chinensis,Syzygium aromaticum,Salvia miltiorrhiza,Punica granatum L. and Terminalia chebula Retz on Ameromonas hydrophila were studied; furthermore,cure rates of the Chinese herb extracts with better anti-bacterial effects were determined to find out the optimal drug dosage. [Result] Under the same experimental conditions,Galla Chinensis,Punica granatum and Terminalia chebula Retz had relatively strong anti-bacterial effects on Ameromonas hydrophila,among them the anti-bacterial effect of Galla Chinensis was significantly higher than those of the others (P0.05). The optimal treatment dose of Galla Chinensis treating bacterial septicemia caused by Aeromonas hydrophila was that they were treated with medicated bath for 40 min by 0.5 mg/ml Galla Chinensis extract,and the cure rate was 100%. [Conclusion] The research provides a scientific drug basis for the control and prevention of outbreak bacterial diseases of fish. 展开更多
关键词 Chinese medicinal herb Galla Chinensis Ameromonas hydrophila Anti-bacterial effect Cure rate
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Measurement and Comparison of Urban Haze Governance Level and Efficiency based on the DPSIR Model:A Case Study of 31 Cities in North China 被引量:10
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作者 XIAO Qinlin TIAN Chao +2 位作者 WANG Yanjun LI Xiuqing XIAO Liming 《Journal of Resources and Ecology》 CSCD 2020年第6期549-561,共13页
In the decisive stage of developing of a moderately prosperous society in all aspects,hazy weather has become a major obstacle to the further advancement of China.Therefore,improving the level and efficiency of haze g... In the decisive stage of developing of a moderately prosperous society in all aspects,hazy weather has become a major obstacle to the further advancement of China.Therefore,improving the level and efficiency of haze governance has become essential.Based on the DPSIR model,this paper builds a haze governance level and efficiency index system using the entropy method and the super-efficiency data envelope-analysis(DEA)model to analyze the data for 31 cities in North China from 2007 to 2016.From the aspects of spatial differences and influence factors influencing the comparative analysis,the results are as follows.(1)During the investigation period,the level and efficiency of city haze governance in North China showed a trend of fluctuation and decline,with obvious stages in their characteristics.Haze governance efficiency is much higher than its level,and its mean value reaches the DEA level which indicates that it is effective.(2)A significant regional gradient difference occurs between these two aspects.The haze governance level presents a convex distribution pattern of"east low–middle high–west low",while the haze governance efficiency presents a concave distribution pattern of"east high–middle low–west high".(3)The regression results show that economic growth has a negative effect on both haze governance level and efficiency.By contrast,the industrial structure has a positive effect on haze governance level and efficiency,but the significance of its effect on these two is different.On this basis,policy suggestions are proposed for improving the level and efficiency of haze governance in various cities in North China. 展开更多
关键词 haze governance level haze governance efficiency entropy method super-efficiency DEA model
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