【摘要】 本文研究了5-Br-PADAP与锌的显色反应,在pH=7.92—9.88氨性缓冲溶液和OP存在下,锌与该试剂形成1:2紫红色络合物,最大吸收波长为552nm,ε=1.3×10~5,锌含量在0—12μg/25ml范围符合比耳定律,并采用六偏磷酸钠、柠檬酸三铵和β-DTCPA等掩蔽荊,消除干扰,本法能应用于直按测定水库水和海水中锌,结果比较满意。更多还原

【Abstract】 In ammonia-ammonium chloride buffer solution at pH 7.92-9.88, Zinc forms a stable complex with 2-(5-brome-2-pyridylazo)-5-diethyl-aminophe-nol(5-Br-PADAP) in the presence of a non-ionic surfactant polyethylenegly-col octylphenylester (OP) , exhibiting maximum absorption at 552nm, the molar absorption coefficient is 1.3×105 L·mol-1·cm-1, obeying Beer’s law in the range 0-12μg/25ml.The interfering ions, such as Cu( Ⅱ ),Pb(Ⅱ), Cd (Ⅱ),Fe (Ⅲ) , Al (Ⅲ) , Ca (Ⅱ) , Mg (Ⅱ) etc, can be masked with masking reagents. The method can be applied to the determination of trace amount of zinc in natural water samples.更多还原