【摘要】 本文用流动注射分析分光光度法测定Ａｌ＿２Ｏ＿３中的ＳｉＯ＿２，利用硅与钼酸铵生成硅钼黄，而后在ｐＨ为１．４～１．７之间和抗坏血酸还原剂生成硅蓝（ε＝２．００×１０￣４）这一特性，在波长λ＝７６０ｎｍ处测定，测定速度为１２０样／ｈ，在ｏ～２０μｇ／ｍＬ浓度范围内服从比尔定律，其检出下限为０．３２２μｇ／ｍＬ与手工法相比，该法分析结果的精密度和重现性都比较好。更多还原

【Abstract】 he paper reports a FIA spectropho-tometric method for the determination ofSiO₂ in Al₂O₃,based on the reaction of sili-con with ammonium molybdate to form the molybdosilicate yellow which is then reducedby ascorbic acid to form molybdenum blue.The absorption maximum of molybdosilicateblue is at 760nm with a molar absorptivity ε=2.00 × 10￣4L·.mol￣（-1）· cm￣（-1）. The sam-pling frequency is 120/s, Beer’s law isobeyed in the concentration range of 0～20μg/mL with a detection limit of 0.322μg/mL.更多还原