【摘要】 乙醇对 DBC-偶氮氯膦与钙的显色反应有明显的增效作用。在40%乙醇存在下,显色反应的 pH 范围加宽,试剂空白值稳定,工作曲线的线性范围扩大,灵敏度提高40%以上。用双波长分光光度法测定时,线性关系得到改善,灵敏度进一步提高。拟定了天然水中钙的直接测定法,结果满意。更多还原

【Abstract】 Ethanol has enhancement effect on colour reaction of calcium with DBC-chlorophosphonazo.In the presence of 40% ethanol,pH range of the colour reaction is expanded and absorbance of reagent blank is stable,linear range of the working curve is obviously expanded and sensitivity is increased by a factor of 1/2.4.By means of dual-wavelength spectrophotometry,the linear relationship is improved and sensitivity is further increased.A method has been developed for direct determination of calcium in natural water with satisfactory results.更多还原