中国科学院青藏高原研究所机构知识库
Advanced  
ITPCAS OpenIR  > 图书馆  > 期刊论文
学科主题: 地理学::自然地理学
题名: Overview of VOC emissions and chemistry from PTR-TOF-MS measurements during the SusKat-ABC campaign: high acetaldehyde, isoprene and isocyanic acid in wintertime air of the Kathmandu Valley
作者: Sarkar, C (Sarkar, Chinmoy)1; Sinha, V (Sinha, Vinayak)1; Kumar, V (Kumar, Vinod)1; Rupakheti, M (Rupakheti, Maheswar)2, 3; Panday, A (Panday, Arnico)4; Mahata, KS (Mahata, Khadak S.)2; Rupakheti, D (Rupakheti, Dipesh)5; Kathayat, B (Kathayat, Bhogendra)3; Lawrence, MG (Lawrence, Mark G.)2
通讯作者: Sinha, V
刊名: ATMOSPHERIC CHEMISTRY AND PHYSICS
发表日期: 2016
卷: 16, 期:6, 页:3979-4003
收录类别: SCI
合作性质: 国际
文章类型: Article
英文摘要: The Kathmandu Valley in Nepal suffers from severe wintertime air pollution. Volatile organic compounds (VOCs) are key constituents of air pollution, though their specific role in the valley is poorly understood due to insufficient data. During the SusKat-ABC (Sustainable Atmosphere for the Kathmandu Valley-Atmospheric Brown Clouds) field campaign conducted in Nepal in the winter of 2012-2013, a comprehensive study was carried out to characterise the chemical composition of ambient Kathmandu air, including the determination of speciated VOCs, by deploying a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) - the first such deployment in South Asia. In the study, 71 ion peaks (for which measured ambient concentrations exceeded the 2 sigma detection limit) were detected in the PTR-TOF-MS mass scan data, highlighting the chemical complexity of ambient air in the valley. Of the 71 species, 37 were found to have campaign average concentrations greater than 200 ppt and were identified based on their spectral characteristics, ambient diel profiles and correlation with specific emission tracers as a result of the high mass resolution (maEuro-a center dot aEuro-Delta maEuro-aEuro parts per thousand > aEuro-4200) and temporal resolution (1aEuro-min) of the PTR-TOF-MS. The concentration ranking in the average VOC mixing ratios during our wintertime deployment was acetaldehyde (8.8 ppb) > methanol (7.4 ppb) > acetone + propanal (4.2 ppb) > benzene (2.7 ppb) > toluene (1.5 ppb) > isoprene (1.1 ppb) > acetonitrile (1.1 ppb) > C8-aromatics ( aEuro parts per thousand 1 ppb) > furan ( aEuro parts per thousand 0.5 ppb)aEuro-aEuro parts per thousand > aEuro-C9-aromatics (0.4 ppb). Distinct diel profiles were observed for the nominal isobaric compounds isoprene (maEuro-a center dot aEuro-zaEuro-aEuro parts per thousand= aEuro-69.070) and furan (maEuro-a center dot aEuro-zaEuro-aEuro parts per thousand= aEuro-69.033). Comparison with wintertime measurements from several locations elsewhere in the world showed mixing ratios of acetaldehyde ( aEuro parts per thousand aEuro-9 ppb), acetonitrile ( aEuro parts per thousand aEuro-1 ppb) and isoprene ( aEuro parts per thousand aEuro-1 ppb) to be among the highest reported to date. Two 'new' ambient compounds, namely formamide (maEuro-a center dot aEuro-zaEuro-aEuro parts per thousand= aEuro-46.029) and acetamide (maEuro-a center dot aEuro-zaEuro-aEuro parts per thousand= aEuro-60.051), which can photochemically produce isocyanic acid in the atmosphere, are reported in this study along with nitromethane (a tracer for diesel exhaust), which has only recently been detected in ambient studies. Two distinct periods were selected during the campaign for detailed analysis: the first was associated with high wintertime emissions of biogenic isoprene and the second with elevated levels of ambient acetonitrile, benzene and isocyanic acid from biomass burning activities. Emissions from biomass burning and biomass co-fired brick kilns were found to be the dominant sources for compounds such as propyne, propene, benzene and propanenitrile, which correlated strongly with acetonitrile (r(2) > 0.7), a chemical tracer for biomass burning. The calculated total VOC OH reactivity was dominated by acetaldehyde (24.0 %), isoprene (20.2 %) and propene (18.7 %), while oxygenated VOCs and isoprene collectively contributed to more than 68 % of the total ozone production potential.
Based on known secondary organic aerosol (SOA) yields and measured ambient concentrations in the Kathmandu Valley, the relative SOA production potential of VOCs were benzeneaEuro-aEuro parts per thousand > aEuro-naphthaleneaEuro-aEuro parts per thousand > aEuro-tolueneaEuro-aEuro parts per thousand > aEuro-xylenesaEuro-aEuro parts per thousand > aEuro-monoterpenesaEuro-aEuro parts per thousand > trimethylbenzenesaEuro-aEuro parts per thousand > aEuro-styreneaEuro-aEuro parts per thousand > aEuro-isoprene. The first ambient measurements from any site in South Asia of compounds with significant health effects such as isocyanic acid, formamide, acetamide, naphthalene and nitromethane have been reported in this study. Our results suggest that mitigation of intense wintertime biomass burning activities, in particular point sources such biomass co-fired brick kilns, would be important to reduce the emission and formation of toxic VOCs (such as benzene and isocyanic acid) in the Kathmandu Valley.
语种: 英语
WOS记录号: WOS:000374702300016
Citation statistics:
内容类型: 期刊论文
URI标识: http://ir.itpcas.ac.cn/handle/131C11/7868
Appears in Collections:图书馆_期刊论文

Files in This Item:
File Name/ File Size Content Type Version Access License
V.16(6) 3979-4003 2016.pdf(6928KB)期刊论文作者接受稿开放获取View 联系获取全文

作者单位: 1.Indian Inst Sci Educ & Res Mohali, Dept Earth & Environm Sci, Sect 81, Manauli Po 140306, Punjab, India
2.Inst Adv Sustainabil Studies, Berliner Str 130, D-14467 Potsdam, Germany
3.Himalayan Sustainabil Inst HIMSI, Kathmandu, Nepal
4.Int Ctr Integrated Mt Dev ICIMOD, Khumaltar, Lalitpur, Nepal
5.Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100101, Peoples R China

Recommended Citation:
Sarkar, C ,Sinha, V ,Kumar, V ,et al. Overview of VOC emissions and chemistry from PTR-TOF-MS measurements during the SusKat-ABC campaign: high acetaldehyde, isoprene and isocyanic acid in wintertime air of the Kathmandu Valley[J]. ATMOSPHERIC CHEMISTRY AND PHYSICS,2016,16(6):3979-4003.
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Sarkar, C (Sarkar, Chinmoy)]'s Articles
[Sinha, V (Sinha, Vinayak)]'s Articles
[Kumar, V (Kumar, Vinod)]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Sarkar, C (Sarkar, Chinmoy)]‘s Articles
[Sinha, V (Sinha, Vinayak)]‘s Articles
[Kumar, V (Kumar, Vinod)]‘s Articles
Related Copyright Policies
Null
Social Bookmarking
Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit
文件名: V.16(6) 3979-4003 2016.pdf
格式: Adobe PDF
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.

 

 

Valid XHTML 1.0!
Copyright © 2007-2017  中国科学院青藏高原研究所 - Feedback
Powered by CSpace