Synthesis, Characterization and Luminescence Properties of Rare Earth Complexes with Bis(Pyridinyl-Amide)

A ligand, N^1, N^4-di （ pyridin-2-yl ） succi- namide （L） and its lanthanide（ IH ） complexes （RE = La, Eu, Tb, Gd, Yb ） were synthesized and characterized in detail. The results indicate that the composition of the binary complexes is determined as [ REL （H2O）2（NO3）2] NO3, that the complexes are 1 ： 1 electrolytes in DMF, and that the Tb^3＋ complex has brightly green fluorescence in a solid state. At the same time, the energy levels of the excited triplet states for the six ligands were determined to be 22989 -1 cm . The fact that the ligand sensitize Tb^3＋ complexes was explained by the relative energy gap between the lowest triplet energy level of the ligand （T） and ^5Dj of Tb^3＋ or Eu^3＋ . When 2000 cm^-1 〈 △E（T-^5D4） 〈 3000 cm^-1, the luminescent intensity of the Tb^3＋ complex is stronger. When 3000 cm^-1〈 △E （T-^5D1）, the luminescent intensity of the Eu^3＋ complex is weak- er or close to nil. This means that the triplet energy level of the ligand is a chief factor that dominates RE^3＋ luminescence.

三联体类半带滤波器组的设计方法

文中提出了一种由3个内核所定义的三联体类半带滤波器组的设计方法。采用了Lagrange半带滤波器组和Remez算法,具体地给出了分解滤波器的设计和重构滤波器的设计。带参数的Bernstein多项式用于构造内核。该滤波器组结构有完全重构,正则性等优点。确定Bernstein多项式的自由参数是利用最小二乘法得到。采用了两个实例,对实例进行了具体对比和分析。得出了这种设计方法很灵活,比较容易设计出不同性能的滤波器组。