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Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the flue gas from two types of waste incinerators (municipal solid waste incinerators and hazardous waste incinerators) the most commonly used in China were investigated in this study. The PCDD/F emissions from the stack gas of the waste incinerators showed a large variation from 0.016 to 0.29 ng I-TEQ m -3 with an average value of 0.103 ng I-TEQ m -3 . The emission factors of PCDD/Fs were in the range of 0.056-0.607 µg I-TEQ t -1 (average 0.235 µg I-TEQ t -1 ) for municipal solid waste incinerators (MSWIs) and 0.07-3.27 µg I-TEQ t -1 (average 1.03 µg I-TEQ t -1 ) for hazardous waste incinerators (HWIs), respectively. It was estimated that 10.2-88.0 mg I-TEQ (average 35.0 mg I-TEQ) and 1.13-53.0 mg I-TEQ (average 17.1 mg I-TEQ) of PCDD/Fs were annually released to the atmosphere, respectively from MSWIs and HWIs. The level and congener patterns of 17 species of PCDD/Fs in the ambient air and in soil samples around the MSWIs and HWIs were investigated to evaluate the influence of PCDD/F emission on the environment. The PCDD/F concentrations in the ambient air from the 5 MSWIs and 4 HWIs ranged from 0.088 to 13.9 pg I-TEQ m -3 with an average value of 0.185 pg I-TEQ m -3 . The soil samples in the vicinity of MSWIs and HWIs presented concentrations between 0.68 and 16.0 ng I-TEQ kg −1 with an average value of 3.98 ng I-TEQ kg -1 . This study showed that PCDD/F emission from the incineration plants had an obvious impact on the surrounding ambient air.

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Novel luminescent vesicles with enhanced emission were successfully achieved for the first time by an amphiphilic europium complex through its spontaneously self-assembly in an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]­PF6). The complex was prepared by europium ions coordinated with terpyridine ligands, which were modified with the hydrophilic ethoxy chains. The enhanced absolute quantum yield and prolonged fluorescence lifetime of complex in vesicles were observed because of the effective shielding of the quench effects caused by both solvent and complex concentration. Compared to the aggregates formed in other solvents, the vesicles obtained in [Bmim]­PF6 showed the best luminescence intensity with the quantum efficiency (37.74%) and luminescent emission lifetime (1.915 ms) both increased about 10 times more. Furthermore, this europium complex was designed to show unsaturated coordination, which made the vesicle luminescence easily quenched when contacting with water. The fluorescence sensing of water with this vesicle as probe was therefore possible, where several unique properties like high sensitivity, low detection limit (0.05 vol %), visible color change, and fast response had been observed. Such designed systems are expected to provide strategies to develop novel supramolecular aggregates in ionic liquids and offer guidance for luminescence detection with facile and wide applications.

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