Estimating the secondary organic aerosol contribution to PM2.5 using the EC tracer method
Estimating the secondary organic aerosol contribution to PM2.5 using the EC tracer method
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DOI：
10.1080/02786820390229084
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发表时间：
2004-01-01
影响因子：
5.2
通讯作者：
Turpin, B
中科院分区：
文献类型：
--
作者：
Cabada, JC;Pandis, SN;Turpin, B
为了估算二次有机气溶胶的浓度，在匹兹堡空气质量研究(PAQS)中，应用EC示踪方法对不同碳质气溶胶采样器进行了一系列测量。在2001年夏季密集期间(2001年7月1日至8月4日)收集了高分辨率测量(2-6小时)和日平均浓度，并用于分析。由于采样伪影和采样周期的不同，PAQS过程中使用的不同采样器所测得的OC和EC浓度存在差异，提出了一种系统的方法来区分SOA对环境OC水平有显著贡献的时段和有机碳和元素碳浓度以初级排放为主的时段。臭氧被用作光化学活动的指示器，以确定该地区可能产生二次有机气溶胶的时期。燃烧源(CO、NO和NOx)的气态示踪剂被用来识别大多数有机碳主要存在的时期。以初级排放为主的时期被用来建立初级有机碳和EC之间的关系，EC是2001年7月不同组测量的初级燃烧产生的碳的示踪剂。据估计，2001年7月宾夕法尼亚州西部约35%的有机碳浓度是次要来源。
The EC tracer method is applied to a series of measurements by different carbonaceous aerosol samplers in the Pittsburgh Air Quality Study (PAQS) in order to estimate the concentration of secondary organic aerosol. High-resolution measurements (2-6 h) and daily averaged concentrations were collected during the summer 2001 intensive (1 July to 4 August 2001) and are used for the analysis. The various samplers used during PAQS show differences in the measured concentrations of OC and EC due to the different sampling artifacts and sampling periods.A systematic approach for the separation of periods where SOA contributes significantly to the ambient OC levels from the periods where organic and elemental carbon concentrations are dominated by primary emissions is proposed. Ozone is used as an indicator of photochemical activity to identify periods of probable secondary organic aerosol production in the area. Gaseous tracers of combustion sources (CO, NO, and NOx) are used to identify periods where most of the OC is primary. Periods dominated by primary emissions are used to establish the relationship between primary OC and EC, a tracer for primary combustion-generated carbon for the different sets of measurements for July 2001. Around 35% of the organic carbon concentration in Western Pennsylvania during July of 2001 is estimated to be secondary in origin.