基于荧光信号的大气生物气溶胶测量方法探讨  

Discussion of the measurement method of ambient bioaerosols based on fluorescent signal

作　　者：任怡[1] 黄晓锋[1] 王志彬 孙天乐 孙杰 张明棣 何凌燕[1] REN Yi;HUANG Xiao-feng;WANG Zhi-bin;SUN Tian-le;SUN Jie;ZHANG Ming-di;HE Ling-yan(Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China;Multiphase Chemistry Department, Max-Planck Institute for Chemistry,Mainz 55128, Germany;Shenzhen Environmental Monitoring Center, Shenzhen 518049, China)

机构地区：[1]北京大学深圳研究生院城市人居环境科学与技术实验室,广东深圳518055 [2]马克斯-普朗克研究所化学研究所,德国美因茨55128 [3]深圳市环境监测中心站,广东深圳518049

出　　处：《中国环境科学》2017年第8期2848-2854,共7页China Environmental Science

基　　金：深圳市科技计划

摘　　要：使用双波段荧光生物气溶胶检测仪(WIBS-4A)于2015年夏季在深圳城市点进行了大气在线观测,得到3个不同荧光通道上(FL1、FL2和FL3)的荧光粒子数浓度分别是0.41cm^(-3),0.61cm^(-3)和0.24cm^(-3).根据荧光阈值将粒子分为7种类型,其中Type B和Type ABC是最丰富的类型,数浓度均值分别是0.214cm^(-3)和0.202cm^(-3).不同类型粒子日变化不同,总体表现为日间低值,晚间高值的特征.Type ABC粒子粒径峰值主要出现在2.2μm,其余粒子主要峰值集中在1.1μm.进一步讨论了非生物成分对生物气溶胶监测的影响,利用黑碳、乙腈和m/z44等污染来源示踪物与不同类型荧光粒子的相关分析和主成分分析,发现多种粒子受到不同非生物性成分的影响,但Type C受到的影响很小,平均浓度为0.016cm^(-3),可能代表真实的生物气溶胶浓度水平.本研究表明在城市环境中,非生物性化合物对基于荧光检测的生物气溶胶结果有较大影响.A Wideband Integrated Bioaerosol Spectrometer(WIBS)was operated continuously from August1to August31in2015at an urban sampling site in Shenzhen,China.The average number concentrations of the three fluorescent channels,i.e.,FL1,FL2and FL3,were0.41,0.61and0.24cm-3,respectively.The fluorescent aerosol particles(FAPs)was further divided into seven types according to their fluorescence thresholds.The mean number concentrations of the two dominant types,i.e.,Type B and Type BC,were0.214cm-3and0.202cm-3.Different diurnal variations of fluorescent particles was also observed,but they generally showed a low value in the daytime and a high value at night.Most of the number size distributions of FAPs showed a peak at1.1μm except Type ABC,whose peak was at2.2μm.In order to discuss the influence of non-biological fluorescence components on bioaerosol measurement,the correlation analysis and principal component analysis among black carbon,acetonitrile,m/z44,and different FAP types were applied.The results showed that most of the FAP types were interfered by different non-biological components,but Type C showed a weak correlation with all the pollution source markers.The mean number concentration of Type C was0.016cm-3,which could be a more reliable value for the real bioaerosols.This study found that non-biological fluorescent components had a large influence on the measurement of bioaerosols based on the fluorescence detection in urban environment.

关 键 词：生物气溶胶 荧光 WIBS 非生物荧光成分 

分 类 号：X513[环境科学与工程—环境工程]