【摘要】 研究乙基罗丹明B 砷钼杂多酸 聚乙烯醇超高灵敏显色体系 ,提出痕量砷测量的新的高灵敏分光光度法 ,缔合物最大吸收位于 5 95nm ,表观摩尔吸光系数ε6 0 1=3.1 2× 1 0 6 L·mol-1·cm-1,是现有文献中利用水相光度法测定砷的最灵敏的方法 .并研究缔合物的组成和红外光谱 .本法直接用于合金钢中痕量砷的测定 ,获得满意结果 .更多还原

【Abstract】 According to investigation of a colour reaction of ethyl rhodamine B molybdoarsenic acid PVA systerm, a super sensitive spectrophtometric method for determination of trace of arsenic is reported. The maximum absorption wavelength of the ion associted compound is at 595 nm and its apparent molar absorptivity was found to be 3.12×10\+6 L\5mol\+\{-1\}\5cm\+\{-1\}. Beer′s law is obeyed in the range of 0 to 0.20 mg of As(V) per 25 L. The colour of the aqueous solution was stable for at least 1 h. The molar ratio of As(V) to ERB\++ in ion associate is established to be 1∶17. Infrared spectra shows that an ionic bond occurs between ERB\++ and H\[As(Mo\-2O\-7)\-6\]\+\{6-\} and that the structure of the dye molecule is not effected by the formation of the ion associate. Trace arsenic in water and in alloy steel can be determined directly by the proposed method with satisfactory results.更多还原