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斜拉-连续梁协作体系桥静力特性研究 被引量:3
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作者 曹前进 赵青 任炜 《洛阳理工学院学报(自然科学版)》 2021年第2期22-28,共7页
近几年,桥梁结构不断优化,斜拉和连续梁桥相互组合的桥梁——斜拉-连续协作体系桥作为一种新型结构逐渐出现,它兼有斜拉桥和连续梁桥的共同优势。为了体现出斜拉-连续梁协作体系的优越性,依托某斜拉-连续梁结构桥梁工程,通过MIDAS CIVI... 近几年,桥梁结构不断优化,斜拉和连续梁桥相互组合的桥梁——斜拉-连续协作体系桥作为一种新型结构逐渐出现,它兼有斜拉桥和连续梁桥的共同优势。为了体现出斜拉-连续梁协作体系的优越性,依托某斜拉-连续梁结构桥梁工程,通过MIDAS CIVIL有限元软件模拟对比斜拉桥、连续梁、桥斜拉-连续协作体系桥3种结构成桥阶段的静力特性数据,包括弯矩、变形等。实验数据表明,在同等跨度下,无论是工程量、成本还是受力情况,斜拉-连续协作体系桥都有一定的优越性,协作体系的挠度值位于斜拉桥和连续梁桥之间,表明协作体系是位于柔性和刚性之间的一种比较理想的新型桥梁结构。 展开更多
关键词 斜拉-连续梁协作体系 斜拉桥 连续梁桥 静力特性
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Local-scale patterns of genetic variation in coexisting floating-leaved Nymphoides peltata and submerged Myriophyllum spicatum in Donghu Lake
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作者 cao qianjin HU Feiyang LIU Na 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第6期1825-1834,共10页
Coexisting floating-leaved and submerged plants experience similar environmental changes but may evolve different patterns of genetic variation.To compare local-scale genetic variation,we collected samples of floating... Coexisting floating-leaved and submerged plants experience similar environmental changes but may evolve different patterns of genetic variation.To compare local-scale genetic variation,we collected samples of floating-leaved Nymphoides peltata and submerged Myriophyllum spicatum coexisting in a disturbed urban lake in China.At the subpopulation level,using microsatellites,M.spicatum had higher clonal diversity than N.peltata.M.spicatum had 28.4%multilocus genotypes(MLGs)shared between subpopulations,but N.peltata had only one MLG shared between two adjacent subpopulations.N.peltata displayed more genetic variation between subpopulations than within subpopulations,but the reverse was true for M.spicatum.Principal components and Bayesian cluster analyses showed that individuals from each subpopulation of N.peltata tended to have relatively close genetic relationships.For M.spicatum,individuals from each subpopulation were genetically scattered with those from other subpopulations.Our results imply that in unpredictable adverse environments M.spicatum may be less subjected to local-deme extinction than N.peltata because of genetically diverse clones at the subpopulation level.This characteristic means that following adverse events,M.spicatum may rapidly restore subpopulation distributions via recolonization and intense gene flow among subpopulations. 展开更多
关键词 aquatic plants life forms microsatellites clonal diversity eutrophic lake
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