中文摘要：

以对二甲氨基苯甲腈（DMABN）为探针,测定它在表面活性剂（C12TABr、SDS、C12E23、C12-3-C12·2Br）水溶液中的第二重荧光强度（Ia）和对应的特征波长（λa）对表面活性剂浓度（c）曲线,由Ia-c曲线的转折点或λa-c曲线对应的一阶导数极小点可以获得临界胶团浓度（cmc）.由于C12-3-C12·2Br在水溶液中强烈聚集,利用λa-c曲线还可以获得其胶团结构松散度的信息.

英文摘要：

With p-N,N-dimethylaminobenzonitrile（DMABN）as a probe,the variations of the intensity of its second fluorescence emission（Ia）and the corresponding characteristic wavelength（λa）with the surfactant concentration（c）,here the examined surfactants（C12TABr,SDS,C12E23,and C12-3-C12·2Br）,were measured by Hitachi F4500 fluorescence spectrophotometer.The results showed that both the break point on the Ia-c curve and the minimum of the derivative variation corresponding to the λa-c curve agreed very well with the critical micelle concentration（cmc）of the surfactant in aqueous solution as measured by surface tension technique.Due to strong aggregation of C12-3-C12·2Br in aqueous solution,the information about loose micellar structure could be obtained by its λa-c curve.