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DOI	10.5194/acp-20-10149-2020
	Laboratory studies of fresh and aged biomass burning aerosol emitted from east African biomass fuels-Part 1: Optical properties
	Smith D.M.; Fiddler M.N.; Pokhrel R.P.; Bililign S.
发表日期	2020
ISSN	1680-7316
起始页码	10149
结束页码	10168
卷号	20 期号:17
英文摘要	An accurate measurement of the optical properties of aerosol is critical for quantifying the effect of aerosol on climate. Uncertainties persist and results of measurements vary significantly. Biomass burning (BB) aerosol has been extensively studied through both field and laboratory environments for North American fuels to understand the changes in optical and chemical properties as a function of aging. There is a need for a wider sampling of fuels from different regions of the world for laboratory studies. This work represents the first such study of the optical and chemical properties of wood fuel samples commonly used for domestic purposes in east Africa. In general, combustion temperature or modified combustion efficiency (MCE) plays a major role in the optical properties of the emitted aerosol. For fuels combusted with MCE of 0:974±0:015, which is referred to as flaming-dominated combustion, the single-scattering albedo (SSA) values were in the range of 0.287 to 0.439, while for fuels combusted with MCE of 0:878±0:008, which is referred to as smoldering-dominated combustion, the SSA values were in the range of 0.66 to 0.769. There is a clear but very small dependence of SSA on fuel type. A significant increase in the scattering and extinction cross section (with no significant change in absorption cross section) was observed, indicating the occurrence of chemistry, even during dark aging for smoldering-dominated combustion. This fact cannot be explained by heterogeneous oxidation in the particle phase, and we hypothesize that secondary organic aerosol formation is potentially happening during dark aging. After 12 h of photochemical aging, BB aerosol becomes highly scattering with SSA values above 0.9, which can be attributed to oxidation in the chamber. Aging studies of aerosol from flaming-dominated combustion were inconclusive due to the very low aerosol number concentration. We also attempted to simulate polluted urban environments by injecting volatile organic compounds (VOCs) and BB aerosol into the chamber, but no distinct difference was observed when compared to photochemical aging in the absence of VOCs. © 2020 Author(s).
语种	英语
scopus关键词	aerosol; albedo; biofuel; biomass burning; chemical property; combustion; laboratory method; optical property; volatile organic compound; East Africa
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/141126
作者单位	Department of Physics, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, United States; Applied Sciences and Technology Program, North Carolina A and T State University, Greensboro, NC 27411, United States; Department of Chemistry, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, United States; Department of Chemistry and Physics, Western Carolina University, Cullowhee, NC 28723, United States
推荐引用方式 GB/T 7714	Smith D.M.,Fiddler M.N.,Pokhrel R.P.,et al. Laboratory studies of fresh and aged biomass burning aerosol emitted from east African biomass fuels-Part 1: Optical properties[J],2020,20(17).
APA	Smith D.M.,Fiddler M.N.,Pokhrel R.P.,&Bililign S..(2020).Laboratory studies of fresh and aged biomass burning aerosol emitted from east African biomass fuels-Part 1: Optical properties.Atmospheric Chemistry and Physics,20(17).
MLA	Smith D.M.,et al."Laboratory studies of fresh and aged biomass burning aerosol emitted from east African biomass fuels-Part 1: Optical properties".Atmospheric Chemistry and Physics 20.17(2020).