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Composition-dependent optical transitions and 2.0 μm emission properties of Ho~(3+) in xGeO_2-(80-x)TeO_2-9.5ZnF_2-10NaF-0.5Ho_2O_3 glasses 总被引:1,自引:0,他引:1
Ho3+ doped glasses with various compositions xGeO2-(80-x)TeO2-9.5ZnF2-10NaF-0.5Ho2O3(x=0,10,20,30,40,50,60,70 and80) were prepared by a melt-quenching technique.The composition-dependent optical transition properties of Ho3+ were investigated in theframework of Judd-Ofelt theory.The emission cross sections for 5I7→5I8 transition of Ho3+ in these glasses were calculated according toMcCumber theory,and their compositional dependence was discussed.A simple method was proposed in calculating the emission cross ... 相似文献
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综述了各种纱线张力测量传感器的优缺点,发明了一种全新的扭转型张力转角传感器,基于霍尔效应原理和独特的机械结构研制的一种高精度的纱线张力测量传感器.机械结构部分主要以游丝产生回复力,使传感器转轴能准确而平稳地回到起始位置点. 相似文献
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大体积混凝土开裂的问题是建筑施工中一个普遍性的技术问题。裂缝一旦形成,特别是基础贯穿裂缝出现在重要的结构部位,危害极大,它会降低结构的耐久性,削弱构件的承载力,同时可能会危害到建筑物的安全使用。本文分析大体积混凝土裂缝的产生原因,然后通过实际案例提出具体的防裂措施。 相似文献
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