多环芳烃由于具有三致（致癌、 致畸、 致突变）特性, 其在环境中的检测受到人们广泛关注。 利用时间分辨光谱技术, 研究了荧蒽乙醇溶液的荧光光谱随延时时间和门宽改变的特性。 研究了不同浓度荧蒽的时间分辨荧光光谱特性, 以原始浓度的荧蒽为初始溶液, 通过逐级稀释的方式, 最终将原始溶液稀释16倍, 拟合了不同稀释倍数下的荧蒽荧光强度衰减随延时时间变化的动力学曲线, 得到了不同浓度荧蒽的拟合荧光寿命。 研究结果表明, 荧蒽的荧光光谱特性与光谱仪探测器延时时间和门宽宽度密切相关。 固定延时时间, 随着光谱仪门宽宽度的变化, 荧蒽的荧光强度随着门宽的增大而逐渐增强。 固定门宽, 改变延时时间的过程中, 荧蒽的荧光强度随延时时间呈现先增大, 后减小的趋势。 荧蒽的荧光强度随延时时间的衰减过程符合指数衰减过程, 将荧蒽乙醇溶液进行逐级稀释, 荧蒽荧光强度与延时时间的衰减进行指数拟合后, 得到不同稀释倍数的荧蒽乙醇溶液的衰减动力学参数, 随着稀释倍数的增大, 拟合得到的荧蒽荧光寿命增大。 多环芳烃时间分辨光谱特征的研究, 可以为环境中多环芳烃的检测提供技术基础, 由于不同荧光物质具有特征的荧光寿命, 因此, 可以利用多环芳烃与环境中其他荧光物质的不同荧光寿命特性, 准确识别环境中的多环芳烃污染物。

Polycyclic Aromatic Hydrocarbons (PAHs) have been widely investigated in environmental field, for most of them are mutagenic (carcinogenic, teratogenic, mutagenic). The influence of delay time and gate width on the time-resolved fluorescence spectroscopy of fluoranthene in ethanol was studied in this paper. Furthermore, laser induced time-resolved fluorescence spectroscopy of fluoranthene with different concentration were also researched. According to the results, fluorescence kinetics decay curves and fluorescence lifetime of fluoranthene matched. The research results showed that there was closely relationship between the fluorescence spectrum of fluoranthene and the delay time and gate width of detector. When the delay time was fixed, the fluorescence intensity of fluoranthene grew increased as the gate width increased. When the gate width was fixed, the fluorescence intensity of fluoranthene increased first and then decreased with the delay time increases. The process of the attenuation of fluorescence intensity of fluoranthene with time delay conformed to the exponential decay process. The stepwise dilution of fluoranthene ethanol solution was also studied. With increasing dilution, the fitting of fluoranthene fluorescence lifetime increased. The results of this paper can provide a technical basis for the detection of PAHs in the environment, due to the different characteristics of the fluorescent substance having fluorescence lifetime.