Daughter Decays Faster than the Parent l 2 2(t)=A1(0) 2 入1t (入2-入1)t 入2-入1 42()→410)x2-x1 入1t transient equilibrium: daughter's decay rate is limited by the decay rate of the parent N<<A2, A(t)→A、N82-A 2 Ait c A1(0) 入1t The activity of the daughter approaches that of the parent. This extreme case is known as secular equilibriun(久期平衡)Daughter Decays Faster than the Parent λI < λ2, transient equilibrium: daughter's decay rate is limited by the decay rate of the parent. λI << λ2, The activity of the daughter approaches that of the parent. This extreme case is known as secular equilibrium(久期平衡)