The relation between contents of cerium and impurity lead or bismuth to their activity coefficient in Ag, Cu and Zn-base alloy was calculated and analyzed by us
The SiO2 adsorbing YF3, Y2 (CO3) 3, Y2 (C2O4) 3 and YPO4, respectively, formed four systems of particle materials: SiO2·YF3, SiO2·Y2 (CO3)3, SiO2·