Methods The stress-relaxation curve of PN powder was measured using Micro Powder Characterizer (MPC-100), and compared with that of frequent-using excipients to find out the most similar curve.

• 方法 利用粉体压缩特性分析仪，建立常用辅料应力缓和曲线数据库，比较三七粉的应力缓和曲线与常用辅料曲线的相似度；