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Study on the Morphological Differences of Four Carp Populations 被引量:1
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作者 李倩 凌去非 +2 位作者 王磊 王大鹏 佟广军 《Agricultural Science & Technology》 CAS 2011年第9期1270-1272,1282,共4页
[Objective] The aim was to discuss the morphological differences of four carp populations.[Method] Based on traditional morphological data(including countable and measurable characters) and framework data,the morpho... [Objective] The aim was to discuss the morphological differences of four carp populations.[Method] Based on traditional morphological data(including countable and measurable characters) and framework data,the morphological differences and phylogenesis of Yellow River carp population(YR),wild four-naris carp population(WF),farmed four-naris carp population(FF) and carp population from Suzhou section of Wusong River(WR) were studied by means of multivariate analysis.[Result] There was no significant difference(P〉0.05) in countable characters among four carp populations.Discriminant analysis showed the discriminating accuracy of YR,WF,FF and WR population were 87.5%,78.1%,73.5% and 96.8% respectively,and the synthetic discriminating accuracy of four populations was up to 83.7%.In addition,cluster analysis revealed that YR population and WF population clustered together,while FF population and WR population clustered together.Principal component analysis indicated that the morphological differences among four populations mainly came from the head,tail and vertical axis of fish.[Conclusion] The study could provide theoretical foundations for the purification and rejuvenation of rare four-naris carp. 展开更多
关键词 Four-naris carp MORPHOLOGY Multivariate analysis
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预激综合征合并心房纤颤的心电图分析 被引量:1
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作者 杜红梅 《中国医学创新》 CAS 2014年第29期33-35,共3页
目的:分析和探讨预激综合征合并心房纤颤的心电图特征及鉴别诊断。方法:分析9例预激综合征合并心房纤颤的心电图的心室率、RR间距的变化范围及QRs波的形态。结果:入选病例的心室率范围为160~230次/min,平均180次/min,当心室率〉... 目的:分析和探讨预激综合征合并心房纤颤的心电图特征及鉴别诊断。方法:分析9例预激综合征合并心房纤颤的心电图的心室率、RR间距的变化范围及QRs波的形态。结果:入选病例的心室率范围为160~230次/min,平均180次/min,当心室率〉180次/min时,各导联均看不到f波;RR问期的变化范围为210~760ms;QRS波群大多表现为完全预激图形,少数呈典型预激图形及正常QRS图形。结论:预激综合征合并心房纤颤的心电图特征为:极其快速的心室率、RR间期绝对不等、QRS波群宽大、形态多变。 展开更多
关键词 预激综合征 心房纤颤 RR间期绝对不等 QRS形态多变
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基于特征参数的井眼轨迹模式识别与分段方法
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作者 刘卫星 杨金显 《电子科技》 2022年第10期65-71,共7页
针对井眼轨迹形态多变而测斜模式单一所导致的井眼轨迹拟合偏离真实钻进轨迹问题,文中提出了基于特征参数的井眼轨迹分段和模式识别方法。该方法基于充分的理论分析建立井斜角、方位角随井深的3次b样条函数,得到能够决定井眼轨迹某点邻... 针对井眼轨迹形态多变而测斜模式单一所导致的井眼轨迹拟合偏离真实钻进轨迹问题,文中提出了基于特征参数的井眼轨迹分段和模式识别方法。该方法基于充分的理论分析建立井斜角、方位角随井深的3次b样条函数,得到能够决定井眼轨迹某点邻近形状的曲线特征参数。根据该特征参数,结合各种模型的特征参数,构建井眼模式识别评价指标和分段指标,并选出最符合实钻的井眼轨迹模型。为了验证所提方法的有效性,设计了样机模拟实钻实验。研究结果表明,基于特征参数的井眼轨迹模式识别与分段方法能够有效提高井眼轨迹拟合的精度。 展开更多
关键词 井眼轨迹 形态多变 单一轨迹模型 井斜角 特征参数 轨迹分段 轨迹模式识别 三次B样条
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Polymorph and morphology of CaCO_3 in relation to precipitation conditions in a bubbling system 被引量:2
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作者 Jian Sun Lisheng Wang Dongfang Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第9期1335-1342,共8页
Simulating the typical carbonation step in a mineral CO_2 sequestration, precipitated calcium carbonate(PCC) was prepared by bubbling CO_2 gas into a rich Ca solution. These carbonation reactions were conducted at thr... Simulating the typical carbonation step in a mineral CO_2 sequestration, precipitated calcium carbonate(PCC) was prepared by bubbling CO_2 gas into a rich Ca solution. These carbonation reactions were conducted at three p H ranges, namely 10.0–9.0, 9.0–8.0, and 8.0–7.0, in which temperature and CO_2 flow rate are additional experimental variables. The PCC obtained in experiments was examined by Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD). It was found that supersaturation determined by p H value and flow rate of CO_2 has significant influence on polymorph of PCC. Vaterite was preferably formed at high supersaturation, while dissolution of metastable vaterite and crystallization of calcite occurred at low supersaturation. High temperature is a critical factor for the formation of aragonite. At 70 °C, vaterite, calcite and aragonite were observed to coexist in PCC because transformation from vaterite to aragonite via calcite occurred at this temperature. Scanning electron microscopy(SEM) technology was performed on prepared PCC, and various morphologies consistent with polymorphs were observed. 展开更多
关键词 Precipitated calcium carbonate Rich Ca solution Bubbling CO2 pH range Polymorph Morphology
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The Evolution of Stinging Hairs and Other Characters in Nettle Family
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《Bulletin of the Chinese Academy of Sciences》 2015年第4期249-249,共1页
Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters(e.g.flower,achene.stipule,... Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters(e.g.flower,achene.stipule,bract)require a microscope for accurate determination.Meanwhile,most Uriiceae species have stinging hairs which make them more difficult to collect and identify.As a result,the infra-familial classification of Urticaceae has been controversial for more than a century.A research group led by Prof. 展开更多
关键词 Family familial controversial morphological bract diagnostic infra flower characters habit
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Photo-induced morphology transition of a multifunctional photochromic bisthienylethene molecule with switchable aggregation-induced emission 被引量:1
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作者 Sheng Wang Fang Wang +3 位作者 Chengpeng Li Teng Li Derong Cao Xiang Ma 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第10期1301-1306,共6页
A novel multifunctional molecule BTE-CNPH was designed and synthesized by connecting 2-(3′,5′-bis(trifluoromethyl)-biphenyl-4-yl)-2-cyanovinyl group to both side of the bisthienylethene(BTE), which exhibited excelle... A novel multifunctional molecule BTE-CNPH was designed and synthesized by connecting 2-(3′,5′-bis(trifluoromethyl)-biphenyl-4-yl)-2-cyanovinyl group to both side of the bisthienylethene(BTE), which exhibited excellent aggregation-induced emission(AIE) and bistable photochromism. High-contrast(>60) reversible fluorescence switching was achieved in the 1 D nanowires, solid of BTE-CNPH and also in a polymethyl methacrylate(PMMA) film loaded with 1% BTE-CNPH under the alternative irradiation by 365 nm and visible light. Interestingly, the nanowire-like assembly morphology of BTE-CNPH in aqueous tetrahydrofuran(THF) solution of specific concentration was observed to translate into amorphous pieces gradually upon prolonged irradiation by the 365 nm, accompanying with photo-tunable AIE emission. 展开更多
关键词 PHOTOCHROMISM bisthienylethene aggregation-induced emission
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