【摘要】 基于朗伯-比尔定律通常只适用于描述一定浓度范围内的染料吸光度随浓度的线性变化关系,研究了大范围浓度的天青1号、结晶紫、罗丹明B、荧光素和亚甲基蓝水溶液的最大吸收峰处吸光度与浓度的关系,获得它们的工作曲线。发现结晶紫和罗丹明B水溶液的工作曲线符合朗伯-比尔定律;而天青1号、荧光素和亚甲基蓝水溶液的工作曲线出现非线性现象。对此,从分子间相互作用、折射率、染料的光稳定性3方面解释了非线性关系出现的原因。分子间相互作用和折射率很可能导致较高浓度区间吸光度与浓度的非线性关系,同时染料的光稳定性可以解释一些染料溶液低浓度区间的非线性关系。更多还原

【Abstract】 Lambert-Beer’s law is usually limited to describe the linear relationship between the dye absorbance and the dye concentration in a certain concentration range. In this paper,we have investigated variances of the absorbance at the maximum absorption peak of Azure Ⅰ,Crystal Violet,Rhodamine B,Fluorescein and Methylene Blue in aqueous solution,respectively,with the dye concentration in a large range,and obtained the nonlinear calibration curves. Lambert-Beer’s law can describe calibration curves of Crystal Violet and Rhodamine B. While it cannot describe calibration curves of AzureⅠ,Fluorescein and Methylene Blue. The variations of intermolecular interaction,refractive index,and light stability have been used to explore the origin of the nonlinear relationship. Intermolecular interaction and refractive index result in the nonlinear relationship between absorbance and concentration of dyes in high concentration. Light stability result in the nonlinear relationship in low concentration. The nonlinear calibration curves obtained here can be used to precisely detect and analyze the dye concentration in aqueous solution.更多还原