用钙离子选择电极测定食品中钙

DETERMINATION OF CALCIUM IN FOOD WITH CALCIUM ION SELETIVE ELECTRODE

当离子强度调节剂为０．１ｍｏｌ·Ｌ－１ＫＣｌ，溶液ｐＨ值为５时，在２．５ｍｌ０．０２ｍｏｌ·Ｌ－１的磺基水杨酸存在下，测定Ｃａ２＋离子的最低浓度为１．０×１０－５ｍｏｌ·Ｌ－１．该法适用于食品中钙的测定，与ＥＤＴＡ络合滴定法结果相吻合．测定的相对平均偏差为４％．

The morphology,component distribution and activity of catalysts containing Zirconium were studied by means of SEM and micro reactor. The results show that the morphology of co precipitation catalyst containig Zirconium exists in amorphism and the distribution of Cu, Zn and Zr component is fair even. The catalysts prepared by various methods have various surface areas,Zirconium distribution and activity. The better Zirconium distribution, the higher the activity of catalyst. The morphology and cmponent distribution of catalyst after being reduced don't obviously chang