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基于同质园栽培的21种淫羊藿属植物花部特征的分类学意义 被引量:2
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作者 易雪倩 何花 +2 位作者 曾罗 舒为杰 杨晓琛 《西北植物学报》 CAS CSCD 北大核心 2023年第8期1415-1426,共12页
以采自中国多地并同质园栽培于吉首大学种质资源圃的21种淫羊藿为研究材料,通过观测这些物种的花梗长、花直径、内萼片长宽、蜜距长、雌雄蕊长、花药长、花柱长、胚珠数、花粉大小及花粉量等16个花部特征数量性状和花序类型、有无蜜距... 以采自中国多地并同质园栽培于吉首大学种质资源圃的21种淫羊藿为研究材料,通过观测这些物种的花梗长、花直径、内萼片长宽、蜜距长、雌雄蕊长、花药长、花柱长、胚珠数、花粉大小及花粉量等16个花部特征数量性状和花序类型、有无蜜距、花瓣颜色、内萼片颜色、内萼片与花瓣相对长度及花粉颜色6个质量性状,并对其分类学意义进行探讨。结果表明,(1)21种淫羊藿内轮萼片花瓣状,4枚花瓣除无距淫羊藿外均特化成蜜距,但花部形态种间存在显著差异,尤其体现于花直径、内萼片长宽、蜜距长、雌蕊长、胚珠数、花粉量、花粉直径等特征。(2)主成分分析显示花直径、内萼片长、花药长、胚珠数和花粉直径等性状信息负荷量较大,在该属分类中起主要作用。(3)根据花部特征聚类分析,物种间区分良好,21物种可分为4支:第1支花小,花瓣短于内轮萼片,囊状距或兜状距;第2支花较大,花瓣远长于内轮萼片,长距状;第3支花小,花瓣没有特化形成蜜距;第4支花较小,花丝伸长明显,可达10 mm,花蜜距呈钻状。(4)依据所观察到的花部形态特征编写了淫羊藿属21种植物花部特征分种检索表。研究认为,基于同质园栽培下的淫羊藿属物种的花部特征具有分类学意义,可以为该属分类提供一定依据。 展开更多
关键词 淫羊藿属 同质园 花部特征 聚类分析 分类学意义
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Measurement of the fluidized velocity in gas-solid fluidized beds based on AE signal analysis by wavelet packet transform 被引量:8
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作者 WANG JingDai YANG YongRong +2 位作者 GE PengFei shu weijie HOU LinXi 《Science China Chemistry》 SCIE EI CAS 2007年第2期284-289,共6页
An energy distribution theory was presented based on regular evolvement of energy fraction of acous-tic signals with fluidization velocity. Wavelet packet analysis was used in processing the acoustic sig-nals originat... An energy distribution theory was presented based on regular evolvement of energy fraction of acous-tic signals with fluidization velocity. Wavelet packet analysis was used in processing the acoustic sig-nals originated from particle impact on the wall of a fluidized bed. A new criterion of judging incipient fluidization(Umf) velocity and minimum turbulent velocity(Umt) was proposed according to the energy distribution theory. Experiments were performed with five groups of high density polyethylene(PE) particles and one bimodal PE to acquire incipient fluidization velocity and minimum turbulent velocity by using the criterion. The feasibility of this method in obtaining characteristic fluidization parameters was further verified by comparing it to results from the pressure drop method and the empirical value from industry. 展开更多
关键词 fluidized BED minimum FLUIDIZATION VELOCITY minimum TURBULENT VELOCITY acoustic emission WAVELET PACKET transform
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