对来自浙江、福建境内石杉科植物蛇足石杉(H up erz ia serra ta)、柳叶马尾杉(P h legm ariurus cryp tom eri-anus)10个不同地理居群的石杉总碱含量进行了测定,并基于紫外光谱,对它们的表型分化进行了除趋势对应分析。结果表明:①石...对来自浙江、福建境内石杉科植物蛇足石杉(H up erz ia serra ta)、柳叶马尾杉(P h legm ariurus cryp tom eri-anus)10个不同地理居群的石杉总碱含量进行了测定,并基于紫外光谱,对它们的表型分化进行了除趋势对应分析。结果表明:①石杉科这两种植物叶片的石杉总碱含量普遍高于茎中的含量;②来自浙江磐安的蛇足石杉居群的叶、茎石杉总碱含量都明显高于其它居群。可以选择该居群作为栽培蛇足石杉的种源;③DCA排序发现,产自磐安的蛇足石杉样品,特别是叶的提取液,其紫外光谱明显不同于其它样品,表明紫外光谱法能够用于鉴别石杉总碱含量较高的蛇足石杉药材。展开更多
The reflected group delay from a multilayer structure comprising a one-dimensional photonic crystal coated with a bulk Dirac semimetal(BDS)separated by a spacer layer is investigated theoretically.It is shown that the...The reflected group delay from a multilayer structure comprising a one-dimensional photonic crystal coated with a bulk Dirac semimetal(BDS)separated by a spacer layer is investigated theoretically.It is shown that the group delay of the reflected beam in this structure can be significantly negatively enhanced and switched from negative to positive.The enhanced group delay originates from the steep phase change caused by the excitation of the optical Tamm state at the interface between the BDS and spacer layer.Moreover,positive and negative group delays can be actively tuned through the Fermi energy and the relaxation time of the BDS.We believe that this enhanced and tunable delay scheme has important research significance for the fabrication of optical delay devices.展开更多
文摘对来自浙江、福建境内石杉科植物蛇足石杉(H up erz ia serra ta)、柳叶马尾杉(P h legm ariurus cryp tom eri-anus)10个不同地理居群的石杉总碱含量进行了测定,并基于紫外光谱,对它们的表型分化进行了除趋势对应分析。结果表明:①石杉科这两种植物叶片的石杉总碱含量普遍高于茎中的含量;②来自浙江磐安的蛇足石杉居群的叶、茎石杉总碱含量都明显高于其它居群。可以选择该居群作为栽培蛇足石杉的种源;③DCA排序发现,产自磐安的蛇足石杉样品,特别是叶的提取液,其紫外光谱明显不同于其它样品,表明紫外光谱法能够用于鉴别石杉总碱含量较高的蛇足石杉药材。
基金Project supported by the Scientific research project of Zhejiang Provincial Department of Education(Grant No.Y202250547)the Scientific Research Project ofWenzhou University of Technology(Grant No.ky202205)the Hunan Provincial Natural Science Foundation of China(Grant No.2022JJ30394).
文摘The reflected group delay from a multilayer structure comprising a one-dimensional photonic crystal coated with a bulk Dirac semimetal(BDS)separated by a spacer layer is investigated theoretically.It is shown that the group delay of the reflected beam in this structure can be significantly negatively enhanced and switched from negative to positive.The enhanced group delay originates from the steep phase change caused by the excitation of the optical Tamm state at the interface between the BDS and spacer layer.Moreover,positive and negative group delays can be actively tuned through the Fermi energy and the relaxation time of the BDS.We believe that this enhanced and tunable delay scheme has important research significance for the fabrication of optical delay devices.
