摘要
报道了太原城区空气颗粒物中多环芳烃(PAHs)化合物的稳定碳同位素组成特征,并讨论了多环芳烃的来源。气相色谱/燃烧系统/同位素质谱(GC/C/IRMS)分析表明,PAHs的1δ3C值在非采暖季为-25.1‰^-27.2‰,采暖季为-23.8‰^-28.6‰。统计表明,不同采样点的样品中PAHs的δ13C区别不明显(0.2‰<σ<0.9‰)。两个季节四环多芳香烃化合物荧蒽、芘和苯并(a)蒽的1δ3C没有明显的区别,δ13C的范围为-23.8‰^-25.9‰。随着分子量的增大其化合物的碳同位素组成富集13C的能力减小,非采暖季的苯并(a)芘、茚并(1,2,3-cd)芘和苯并(ghi)苝的1δ3C值分别为-27.2‰-、26.5‰和-25.4‰,采暖季为-26.1‰-、28.6‰和-24.1‰。利用二元复合同位素模型,估算了机动车尾气和煤的燃烧对太原城区苯并(a)芘、茚并(1,2,3-cd)芘和苯并(ghi)苝的贡献,机动车尾气排放对苯并(a)芘、茚并(1,2,3-cd)芘和苯并(ghi)苝的贡献率分别为50%、44%和35%;煤的燃烧产生的烟尘对其贡献为50%、56%和65%,太原市城区五环和六环多环芳烃污染是机动车排放和煤的燃烧为主的复合性污染。
Carbon isotopic compositions and apportion sources of atmospheric polycyclic aromatic hydrocarbons （PAHs） in the urban area of Taiyuan are reported. Carbon isotope ratios were measured with GC-C-irMS. δ^13C values of atmospheric PAHs range from -25.1‰ to -27.2‰ in non-heating season and from -23.8‰ to -28.6‰ in heating season. Statistic results show that δ^13C values of atmospheric PAHs are similar at different sample sites （0.2‰ 〈 σ 〈0.9‰）. δ^13C values of 4-ring compounds are similar in heating and no-heating seasons, ranged from-23.8‰ -25.9‰. With the increase of molecular weight, 5, 6-ring compounds are more depleted in ^13C.δ^13C values of benzo[a]pyrene, indeno[1,2,3-cd]pyrene, and benzo[ghi] perylene are-27.2‰, -26.5‰ and -25.4‰ in non-heating season respectively, and -26.1‰, -28.6‰ and -24.1‰ in heating season respectively. Isotope mass balance calculations using a two-end model show that approximately 46 %, 50 % and 60 % of benzo[a] pyrene, indeno[1,2,3-cd] pyrene and benzo[ghi] perylene might be derived from automobile exhausts , and 54%,50% and 40% from soot of coal combustion. Obviously, it is important to control the soot of coal combustion and automobile exhausts in order to reduce the atmospheric PAHs in urban area of Taiyuan.
出处
《太原理工大学学报》
CAS
北大核心
2007年第6期503-506,共4页
Journal of Taiyuan University of Technology
基金
山西省自然科学基金资助项目(20051019)
太原理工大学创新基金资助项目(2005)
关键词
碳同位素
多环芳烃
空气颗粒物
源解析
太原
carbon isotope
polycyclic aromatic hydrocarbons
atmospheric particles
sources apportionment
Taiyuan
