[Study on the Preparation of Ba3Si6O9N4 : Eu(2+) Phosphor and the Characterization of Their Luminescence Properties].

Ba3Si6O9N4 : Eu(2+) phosphors were synthesized by two-step synthesis processes based on high temperature solid phase using BaSiO3 as a precursor. The influence mechanism of the Eu(2+) doping concentration to the luminescence properties of Ba3Si6O9N4 : Eu(2+) phosphors were mainly investigated. This paper made a comparison between the luminescence properties of Ba3Si6ON4 : Eu(2+) phosphors prepared by two-step processes and solid- state reaction method.

Unusual cold crystallization behavior in physically aged poly(L-lactide).

A comparative study of cold crystallization behavior in poly(L-lactide) (PLLA) annealed below and just above the glass transition temperature (T(g)) has been conducted. Annealing benefits the generation of local order and the subsequent cold crystallization process, which becomes significant in PLLA annealed just above T(g). Surprisingly, morphological observation reveals high density nuclei in PLLA annealed below T(g), contrary to its relatively slow crystallization kinetics.