2. The 2, 6 dipicrylamino 3, 5 dinitro pyridine(PYX)
pureness reference material had been certificated by potentiometric method.
用电位滴定法对2,6-双(苦氨基)-3,5-二硝基吡啶(PYX)标准物质的纯度进行测定。
3. Unusual shapes, flamboyant colors, elaborate handcraft, and delicate design show its rustic
pureness, free romance and ancient culture.
其造型夸张,色彩艳丽,做工精简,智用灵巧,具有质朴纯真、自由浪漫、古风犹存的特征。