【摘要】 以芘为探针，利用其在胶束中形成激基二聚体后，芘分子荧光自猝灭的特性，首次测定了十二烷基甜菜碱（Ｃ_１２Ｂｅ）在ｐＨ＝２．０和８．０时的聚集数，以及ＮａＣｌ浓度和表面活性剂复配对其聚集数的影响．当ＮａＣｌ浓度从０．１ｍｏｌ·Ｌ￣－１增加到０．８ｍｏｌ·Ｌ￣－１时，Ｃ_１２Ｂｅ的聚集数分别从１７８增加到２４１（ｐＨ＝２．０）和从１５１增加到２１０（ｐＨ＝８．０）．在ｐＨ＝２．０时，Ｃ_１２Ｂｅ／十二烷基磺酸钠（Ａｓ）复配体系的聚集数随Ａｓ的摩尔分数ｘ_ＡＳ的变化而变化。当ｘ_ＡＳ从０．０５到０．１时，聚集数从４０６增加到６２２；ｘ_ＡＳ从０．８到０．９５时，聚集数从９３１下降到３３９．当０．１＜ｘ_ＡＳ＜０．８时复配体系产生沉淀。当十六烷基三甲基溴化铵（ＣＴＡＢ）的摩尔分数ｘ_ＣＴＡＳ从０．１增加到０．７时，Ｃ_１２Ｂｅ／ＣＴＡＳ复配体系（ｐＨ＝８．０）的聚集数从２８０增加到６０７．更多还原

【Abstract】 Abstract The dynamic quenching of pyrene molecule by the excimer formation in micelles has been used to study the aggregation number（N） of aqueous micellar systems of dodecylbetaine （C₁2Be）,C₁2Be/sodium dodeyl sulfonate（As）and C₁2Be/centyltrimethylammonium bromide （CTAB ）.It is observed that at pH=2.0 and 8.0 the N of C₁2Be increased from 178 to 241 and from 151 to 210 respectively when the concentration of NaCl increased from 0.1mol·L￣-1 to 0.8mol·L￣-1. The N of C₁2Be/As system at pH= 2.0 varied with the variation of the molar ratio of As（x_AS）. The N increased from 406 to 622 when x_AS increased from 0.05 to 0.1, and decreased from 931 to 339 when x_AS increased from 0.8 to 0.95. Precipitation occured when 0.1<x_AS<0.8. At pH= 8. 0 the N of C₁2Be/CTAB system increased form 280 to 607 when the molar ratio of CFAB increased from 0.1 to 0.7.更多还原