天然水中Ca^(2+)的双波长分光光度法测定

Determination of Ca^(2+) in Natural Water by Dual-Wavelength Spectrophotometry

依据胶体颗粒与入射光有A=φε^(-2)λ^(-ε)关系,又φε^(-6)与CaC_2O_4-乙醇胶体体系中的Ca^(2+)浓度呈正相关,φ、ε分别为胶粒的粒数函数和粒径函数。选择两个测定波长λ_1和λ_2,解联立方程,计算φ和ε,由φ和ε求Ca^(2+)浓度。方法的线性范围为0～20μg/ml,最低检出浓度为0.4μg/ml。

Optical behaviour of colloidal particles A=ψε^(-2)λ^(-3),both wavelengths were chose as optical quantitative determination of Ca^(2+) from CaC_2O_4. Relation of ψε^(-6) withCa^(2+) concentration was linear, and ψ and ε were functions of colloidal particles and diameter of particles respectively. Range of linear relation was 0-20 μg/ml and detection limit of Ca^(2+) was 0.4 μg/ml.