三番“讲评”,三次提升

提高学生解题能力是数学教学的重要任务.许多教师只关注学生做题数量、类型与结果,认为只要学生大运动量做题、做各种类型的题,就可以提高解题速度与能力,而对于讲评并不十分关注,甚至对讲评的理解往往局限于分析学生的错误或提供解答,有时甚至把讲评变成公布分数与排列名次.     

Polarized Emission of an Eu^3＋ Doped Azo-Polymer Waveguide

We investigate the polarized emission behaviour of an Eu^3 doped azo-polymer waveguide. Affected by the azobenzene groups in the photoinduced orientation process by the 532nm linearly polarized laser, the ligands were realigned orderly perpendicular to the direction of the orientation direction. This leads to the polarized absorption and emission of the waveguide in the orientation direction. By an m-line apparatus based on the prism coupling technique, two guided propagation modes were observed in the waveguide, and the refractive index at 650hm in TE polarizations is 1. 7505.