Performance of an Aerodyne Aerosol Mass Spectrometer (AMS) during Intensive Campaigns in China in the Summer of 2006
An Aerodyne quadrupole aerosol mass spectrometer (AMS) was deployed in China in the summer of 2006. The measurements were made in the Pearl River Delta region in July 2006 (PRD campaign) and also in Beijing in August-September 2006 (CAREBEIJING campaign). The AMS successfully measured size-resolved chemical composition of submicron non-refractory aerosol (vaporized at 600°C in vacuum) with a time resolution of 10 min, although some quantification issues have been identified. We observed extremely large signals at m/z 39 (39K+) and 41 (41K+), which significantly exceeded m/z 28 (N+2) signals. We also found large signals of m/z 85 (85Rb+), 87 (87Rb+), and 133 (Cs+). Laboratory experiments suggest that the large enhancement of K+ could have been due to the presence of K-containing particles in ambient air. The interferences of alkali metals at m/z 41, 85, 87, and 133 were significant and need to be corrected for better quantification of organic aerosol. The AMS measurements are compared with other, collocated measurements: a particle-into-liquid sampler combined with an ion chromatograph (PILS-IC), a Sunset Laboratory semi-continuous carbonaceous aerosol analyzer, and a Berner impactor sampler followed by off-line ion chromatography analysis (for major inorganic ions). We have found good agreement between the AMS and the other instruments when we assume an AMS particle collection efficiency (CE) of 0.5 for the PRD data and CE = 1.0 for the CAREBEIJING data. These results suggest that the AMS CE could be significantly different in different locations. Possible factors affecting the variability in the CE values are discussed.
No References for this article.
No Supplementary Data.
Document Type: Research Article
Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan
Institute of Low Temperature Science, Hokkaido University, Sapporo, Hokkaido, Japan
Mechanical and Aeronautical Engineering, University of California, Davis, California, USA
Leibniz Institute for Tropospheric Research, Leipzig, Germany
College of Environmental Sciences, Peking University, Beijing, China
Publication date: 2009-03-01
More about this publication?