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作 者 ：何斌

期 刊 ：植物营养与肥料学报 1997年 3卷 1期 页码：66-71

关键词：铁测定；硫氰酸钾；邻菲啰啉；吐温-20；植物；分光光度法；

摘 要 ：本文研究了在吐温-20存在下，于硝酸介质中，铁（Ⅲ）与硫氰酸钾和邻菲啉的显色反应房件。结果表明，所形成的红色配合物的最大吸收波长为518nm，表观摩尔吸光系数为2.06×10⁴L·mol^-1·cm^-1，铁（Ⅲ）含量在0～50μg范围内服从比耳定律。本法具有操作简便，选择性高，重复性好等优点，可不经分离和掩蔽，直接用于植物中铁的测定，结果满意。

Abstract:It is reported that iron(Ⅲ) forms a red complex with potassium thiocyanate and 1,10-phenanthroilne in the presence of Tween-20 and in nitric acid solution. The absorption maximum wavelength of the complex is 518nm. and it‘s apparent mole absorptivity is 2. 06× 10⁴ L· mol^-1· cm^-1. Beer‘s law is obeyed for iron in the range of 0-50μ g/25mL,correlation coefficient is 0. 9999. The advantages of this method are simple operation. less time-consuming. high selectivity and repeatability. It has been applied to determine iron in plant with satisfactory results, without the need for preliminary separation and masking steps.

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