Intercomparison and evaluation of four semi-continuous PM2.5 sulfate instruments
Intercomparison and evaluation of four semi-continuous PM2.5 sulfate instruments
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DOI：
10.1016/s1352-2310(03)00351-0
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发表时间：
2003-08-01
影响因子：
5
通讯作者：
Demerjian, KL
中科院分区：
文献类型：
--
作者：
Drewnick, F;Schwab, JJ;Demerjian, KL
开发和评估时间分辨（分钟）测量技术来表征大气中环境气溶胶/颗粒物的物理和化学组成，对于我们加深对气溶胶过程科学、来源归因和人口暴露的理解至关重要。 2001 年夏季在纽约皇后区举行的 PMTACS-NY 活动期间，部署了各种在线气溶胶分析仪器以及气相和过滤采样技术。在这里，我们报告了四台半连续 PM2.5 硫酸盐仪器的相互比较，以及在同一地点收集的一组 6 小时和三组 24 小时过滤器测量对这些仪器的评估。半连续仪器包括气溶胶质谱仪、颗粒液体进样器与离子色谱仪、Rupprecht & Patashnick 硫酸盐监测仪 (R&P 8400S) 以及由哈佛大学公共卫生学院的 George Allen 开发并由我们中的一位 (J.J.S.) 在现场建造的连续硫酸盐监测仪。我们发现四个半连续仪器之间具有出色的几乎一对一的相关性，典型的多重 R 平方值 >0.9。此外，半连续数据与过滤器测量的相关性也是高度线性的（R-2 0.86-0.98），但半连续仪器仅回收过滤技术收集的硫酸盐质量的约85%。对于这种偏差最可能的解释是过滤器上的正采样伪影（收集直径大于 2.5 µm 的颗粒、过滤器上的氧化/冷凝过程）与半连续测量的负偏差（入口管线损失、低于约 0.1 µm 的小颗粒的收集效率有限）的组合。 (C) 2003 Elsevier Ltd. 保留所有权利。
The development and evaluation of time-resolved (minutes) measurement technologies to characterize the physical and chemical make up of ambient aerosols/particulate matter in the atmosphere are essential to our improved understanding of aerosol process science, source attribution, and population exposure. During the PMTACS-NY summer 2001 campaign in Queens/New York, a wide variety of on-line aerosol analysis instruments were deployed together with gas-phase and filter sampling techniques. Here, we report on the intercomparison of four semi-continuous PM2.5 sulfate instruments and evaluation of these instruments with one set of 6h and three sets of 24-h filter measurements, collected at the same site. The semi-continuous instruments were an aerosol mass spectrometer, a particle-into-liquid sampler coupled with ion chromatograph, a Rupprecht & Patashnick Sulfate Monitor (R&P 8400S), and a continuous sulfate monitor developed by George Allen at Harvard School of Public Health and built in the field by one of us (J.J.S.). We found an excellent almost one-to-one correlation between the four semi-continuous instruments with typical multiple R-squared values >0.9. In addition, the correlations of the semi-continuous data with the filter measurements are also highly linear (R-2 0.86-0.98) but the semi-continuous instruments recover only about 85% of the sulfate mass collected by the filter techniques. The most likely explanation for this deviation is a combination of positive sampling artifacts on the filters (collection of particles with diameter greater then 2.5 mum, oxidation/condensation processes on the filters) with negative biases of the semi-continuous measurements (inlet line losses, limited collection efficiency for small particles below ca. 0.1 mum). (C) 2003 Elsevier Ltd. All rights reserved.