Based on on-line single particle aerosol mass spectrometry （SPAMS） with high time resolution, the sources of atmospheric fine particu- late matter in Nan＇ao County were analyzed. The results showed that during the ...Based on on-line single particle aerosol mass spectrometry （SPAMS） with high time resolution, the sources of atmospheric fine particu- late matter in Nan＇ao County were analyzed. The results showed that during the monitoring period from March 24 to 27 in 2015, the primary source of fine particulate matter in Nao＇ao County was motor vehicle exhaust, that is, 24.7% of fine particulates were from motor vehicle exhaust, followed by biomass burning （17.2%）, fire coal （17.2%）, and sea salt （13.3%）. The proportions of fire coal and sea salt revealed the peculiarity of sources of atmospheric fine particulate matter in Nan＇ao County. Therefore, it is suggested that some measures should be adopted to limit tourist traffic to reduce the adverse impact of motor vehicle exhaust on ambient air quality in Nan＇ao County.展开更多
目的 了解黄精叶绿茶主要香气成分,探明黄精叶绿茶和龙井绿茶的香气成分差异。方法 采用全二维气相色谱-飞行时间质谱法(comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry,GC×GC-TOF MS)分析...目的 了解黄精叶绿茶主要香气成分,探明黄精叶绿茶和龙井绿茶的香气成分差异。方法 采用全二维气相色谱-飞行时间质谱法(comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry,GC×GC-TOF MS)分析两种绿茶香气成分组成与相对含量。结果 两种绿茶共鉴定出332种成分,归属为醇、酮、饱和烷烃、烯烃、醛、酯、吡嗪、芳烃、酸、胺、醚、环氧烷、环烷烃、酚、呋喃、呋喃酮、酰胺、吡咯啉、酸酐、硫化物、卤代烃、含氮化合物、含氧化合物、杂环化合物、氮氧化物等26类化合物。黄精叶绿茶鉴定出225种挥发性成分,龙井绿茶鉴定出200种挥发性成分,共有成分93种。醇类均为含量最高的种类,占黄精叶绿茶香气总含量的26.47%,占龙井绿茶香气总含量的30.94%。黄精叶绿茶的醛类含量仅次于醇类,占21.75%,而龙井绿茶的烯烃类含量仅次于醇类,占14.33%。结论 38种挥发性化合物在二者中相对含量较高,其中戊醇、苯甲醇、苯甲醛在黄精叶绿茶中相对含量较高,对其香气品质可能具有直接影响。与之不同的是,龙井绿茶中反式-2-戊烯-1-醇、(R)-1-甲基-5-(1-甲基乙烯基)环己烯等挥发性化合物相对含量较高。同时相对含量不高的低阈值挥发性化合物也可能是形成黄精叶绿茶香型的关键香气(如α-紫罗兰酮等)。这有利于后续深入研究黄精叶绿茶香气成分的化学组成,为黄精叶制成茶叶提供数据支持。展开更多
基金Supported by the Science and Technology Funding Project of Shantou City,China([2015]106)
文摘Based on on-line single particle aerosol mass spectrometry （SPAMS） with high time resolution, the sources of atmospheric fine particu- late matter in Nan＇ao County were analyzed. The results showed that during the monitoring period from March 24 to 27 in 2015, the primary source of fine particulate matter in Nao＇ao County was motor vehicle exhaust, that is, 24.7% of fine particulates were from motor vehicle exhaust, followed by biomass burning （17.2%）, fire coal （17.2%）, and sea salt （13.3%）. The proportions of fire coal and sea salt revealed the peculiarity of sources of atmospheric fine particulate matter in Nan＇ao County. Therefore, it is suggested that some measures should be adopted to limit tourist traffic to reduce the adverse impact of motor vehicle exhaust on ambient air quality in Nan＇ao County.
