气候变化领域集成服务门户(CCPortal): Detection of tar brown carbon with a single particle soot photometer (SP2)

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DOI	10.5194/acp-19-15673-2019
	Detection of tar brown carbon with a single particle soot photometer (SP2)
	Corbin J.C.; Gysel-Beer M.
发表日期	2019
ISSN	16807316
起始页码	15673
结束页码	15690
卷号	19 期号:24
英文摘要	We investigate the possibility that the refractory, infrared-light-Absorbing carbon particulate material known as "tarballs" or tar brown carbon (tar brC) generates a unique signal in the scattering and incandescent detectors of a single particle soot photometer (SP2). As recent studies have defined tar brC in different ways, we begin by reviewing the literature and proposing a material-based definition of tar. We then show that tar brC results in unique SP2 signals due to a combination of complete or partial evaporation, with no or very little incandescence. Only a subset of tar brC particles exhibited detectable incandescence (70 % by number); for these particles the ratio of incandescence to light scattering was much lower than that of soot black carbon (BC). At the time of incandescence the ratio of light scattering to incandescence from these particles was up to 2-fold greater than from soot (BC). In our sample, where the mass of tar was 3-fold greater than the mass of soot, this led to a bias of <5 % in SP2-measured soot mass, which is negligible relative to calibration uncertainties. The enhanced light scattering of tar is interpreted as being caused by tar being more amorphous and less graphitic than soot BC. The fraction of the tar particle which does incandesce was likely formed by thermal annealing during laser heating. These results indicate that laser-induced incandescence, as implemented in the SP2, is the only BC measurement technique which can quantify soot BC concentrations separately from tar while also potentially providing real-Time evidence for the presence of tar. In contrast, BC measurement techniques based on thermal-optical (EC: elemental carbon) and absorption (eBC: equivalent BC) measurements cannot provide such distinctions. The optical properties of our tar particles indicate a material similarity to the tar particles previously reported in the literature. However, more-and less-graphitized tar samples have also been reported, which may show stronger and weaker SP2 responses, respectively. . © 2019 BMJ Publishing Group. All rights reserved.
语种	英语
scopus关键词	absorption; black carbon; brown carbon; calibration; evaporation; light scattering; photometer; soot; tar
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/143951
作者单位	Metrology Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen, PSI 5232, Switzerland
推荐引用方式 GB/T 7714	Corbin J.C.,Gysel-Beer M.. Detection of tar brown carbon with a single particle soot photometer (SP2)[J],2019,19(24).
APA	Corbin J.C.,&Gysel-Beer M..(2019).Detection of tar brown carbon with a single particle soot photometer (SP2).Atmospheric Chemistry and Physics,19(24).
MLA	Corbin J.C.,et al."Detection of tar brown carbon with a single particle soot photometer (SP2)".Atmospheric Chemistry and Physics 19.24(2019).