DOI: 10.1016/j.atmosenv.2014.02.024
Scopus记录号: 2-s2.0-84895772084
论文题名: Using total OH reactivity to assess isoprene photooxidation via measurement and model
作者: Nölscher A ; C ; , Butler T ; , Auld J ; , Veres P ; , Muñoz A ; , Taraborrelli D ; , Vereecken L ; , Lelieveld J ; , Williams J
刊名: Atmospheric Environment
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 89 起始页码: 453
结束页码: 463
语种: 英语
英文关键词: Hydroxyl radical
; Isoprene photooxidation
; Mainz isoprene mechanism extended MIME
; Master chemical mechanism MCM 3.2
; Total OH reactivity
Scopus关键词: Atmospheric chemistry
; Degradation
; Ketones
; Oxidation
; Photooxidation
; Sun
; Uncertainty analysis
; Hydroxyl radicals
; Isoprene photooxidations
; Mainz isoprene mechanism extended MIME
; Master chemical mechanism
; Total OH reactivities
; Isoprene
; acrolein
; formaldehyde
; hydroxyl group
; isoprene
; ketone
; methacrolein
; methylvinyl ketone
; unclassified drug
; anthropogenic effect
; atmospheric chemistry
; atmospheric modeling
; biogenic emission
; hydroxyl radical
; isoprene
; oxidant
; photooxidation
; analytic method
; article
; degradation kinetics
; oxidation
; photooxidation
; priority journal
; proton transfer reaction
; time of flight mass spectrometry
; Comunidad Valencia
; Spain
Scopus学科分类: Environmental Science: Water Science and Technology
; Earth and Planetary Sciences: Earth-Surface Processes
; Environmental Science: Environmental Chemistry
英文摘要: The Tropics provide a reactive atmospheric environment with high levels of biogenic emissions, rapidly growing anthropogenic influence, high solar radiation and temperature levels. The major reactive biogenic emission is isoprene which reacts rapidly with the primary daytime oxidant OH, the hydroxyl radical. This key photooxidation process has recently been the focus of several experimental and computational studies. A novel isoprene degradation mechanism was recently proposed (MIME) supplementing the commonly used MCM 3.2 scheme. This study examined the photooxidation of isoprene in the controlled conditions of the Valencia atmospheric reaction chamber, EUPHORE (EUropean PHOto. REactor). Besides the detection of isoprene and its major oxidation products formaldehyde, methyl vinyl ketone (MVK) and methacrolein (MACR), the total loss rate of OH (total OH reactivity) was measured. The total OH reactivity was compared to the individual measurements of isoprene and its oxidation products to assess the significant contributors to the overall OH loss rate. Measured total OH reactivity showed excellent agreement to the calculation based on individual compounds detected by a Proton- Transfer- Reaction- Time- Of- Flight- Mass- Spectrometer (PTR-TOF-MS). On average 97% of the measured total OH reactivity could be explained by isoprene and its major oxidation products.Total OH reactivity was also compared to various isoprene degradation schemes to evaluate known mechanisms. The MCM 3.2 isoprene mechanism reproduced the temporal degradation of total OH reactivity (and isoprene) reasonably well with a 57% (and 95%) agreement within the model uncertainties and a linear curve fit slope of 0.69 (and 1.02) for a model to measurement correlation. Large discrepancies between modeled values and all observed compounds were found for the recent isoprene oxidation scheme in MIME. Possible mechanistic reasons are discussed and improvements proposed. The subsequently modified version of MIME differed from the measured total OH reactivity only about 12% at the end of the experiment and represented best the overall temporal profile (linear curve fit slope of correlation: 0.95). © 2014 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/81196
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Atmospheric Chemistry, Max Planck-Institute for Chemistry, Mainz, Germany; Institute for Advanced Sustainability Studies, Potsdam, Germany; Instituto Universitario CEAM-UMH, Paterna, Valencia, Spain; Department of Chemistry and Biochemistry, University of Windsor, Windsor, Canada; NOAA Earth System Research Laboratory, Boulder, United States
Recommended Citation:
Nölscher A,C,, Butler T,et al. Using total OH reactivity to assess isoprene photooxidation via measurement and model[J]. Atmospheric Environment,2014-01-01,89