Digital plant canopy imager and photosynthesis analyzer system were used to analyze thecharacteristics of canopy structure, photosynthetic physiology and micro-environmentalfactors at R4-R5 stage in different yielding...Digital plant canopy imager and photosynthesis analyzer system were used to analyze thecharacteristics of canopy structure, photosynthetic physiology and micro-environmentalfactors at R4-R5 stage in different yielding soybean cultivars or lines with differentmaturities. The results showed that the common characteristics of high yielding soybeancultivars were high LAI, uniform foliage distribution in all horizontal directions, lessvariance of photosynthetic rate between top and bottom leaves in canopy and relativelyhigher photosynthetic rate of the whole canopy. All these characters combined in allresulted in higher canopy photosynthetic productivity, and pod number, seed number andseed weight per plant, especially pod and seed number in top and middle canopy wereincreased. The characters of high yielding canopy varied among maturities. Light interceptionwas more important to early cultivars. Less foliage inclination angle was benefit tointercept more solar energy during yield formation. As late soybean cultivars had a moreclosure canopy and higher LAI, greater foliage inclination angle in all layers of highyielding canopy made more solar radiation penetrate into canopy, which was beneficial toyield formation.展开更多
粒子加速器的工作性能受电子云效应的严重影响,二次电子产额(Secondary electron yield,SEY)是评判电子云效应的重要参数。利用激光刻蚀技术加工真空室内表面可以有效抑制真空室内二次电子发射,缓解电子云效应。无氧铜材料凭借其高电导...粒子加速器的工作性能受电子云效应的严重影响,二次电子产额(Secondary electron yield,SEY)是评判电子云效应的重要参数。利用激光刻蚀技术加工真空室内表面可以有效抑制真空室内二次电子发射,缓解电子云效应。无氧铜材料凭借其高电导率、高热导率和良好的辐射屏蔽性能成为建造新一代粒子加速器真空室的首选材料。由于粒子加速器真空室的建造周期长,在其制造、安装、调试过程中,刻蚀部件将不可避免地面临长期储存的问题。为研究大气贮存对刻蚀部件二次电子发射的影响,文章采用激光刻蚀技术对无氧铜材料进行表面处理,测试并分析刻蚀前后样品的表面特性与SEY。在样品贮存期间,定期对刻蚀样品进行SEY测试。结果表明,随着贮存时间的延长,刻蚀无氧铜的SEY逐渐升高。表面化学状态的变化是造成SEY上升的主要原因。文章将为未来加速器的真空室表面处理提供一种可行方法,为激光刻蚀部件的贮存方法提供实验支撑。展开更多
基金This research was granted by Heilongjiang Province Natural Science Foundation for Outstanding Young Scientist Award(JT01-02)a part of Knowledge Innovation Project from Chinese Academy of Sciences(KZCX2-SW-416-3).
文摘Digital plant canopy imager and photosynthesis analyzer system were used to analyze thecharacteristics of canopy structure, photosynthetic physiology and micro-environmentalfactors at R4-R5 stage in different yielding soybean cultivars or lines with differentmaturities. The results showed that the common characteristics of high yielding soybeancultivars were high LAI, uniform foliage distribution in all horizontal directions, lessvariance of photosynthetic rate between top and bottom leaves in canopy and relativelyhigher photosynthetic rate of the whole canopy. All these characters combined in allresulted in higher canopy photosynthetic productivity, and pod number, seed number andseed weight per plant, especially pod and seed number in top and middle canopy wereincreased. The characters of high yielding canopy varied among maturities. Light interceptionwas more important to early cultivars. Less foliage inclination angle was benefit tointercept more solar energy during yield formation. As late soybean cultivars had a moreclosure canopy and higher LAI, greater foliage inclination angle in all layers of highyielding canopy made more solar radiation penetrate into canopy, which was beneficial toyield formation.
文摘粒子加速器的工作性能受电子云效应的严重影响,二次电子产额(Secondary electron yield,SEY)是评判电子云效应的重要参数。利用激光刻蚀技术加工真空室内表面可以有效抑制真空室内二次电子发射,缓解电子云效应。无氧铜材料凭借其高电导率、高热导率和良好的辐射屏蔽性能成为建造新一代粒子加速器真空室的首选材料。由于粒子加速器真空室的建造周期长,在其制造、安装、调试过程中,刻蚀部件将不可避免地面临长期储存的问题。为研究大气贮存对刻蚀部件二次电子发射的影响,文章采用激光刻蚀技术对无氧铜材料进行表面处理,测试并分析刻蚀前后样品的表面特性与SEY。在样品贮存期间,定期对刻蚀样品进行SEY测试。结果表明,随着贮存时间的延长,刻蚀无氧铜的SEY逐渐升高。表面化学状态的变化是造成SEY上升的主要原因。文章将为未来加速器的真空室表面处理提供一种可行方法,为激光刻蚀部件的贮存方法提供实验支撑。
