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Tan W, Zhu L, Mikoviny T, Nielsen CJ, Tang Y, Wisthaler A, Eichler P, Müller M, D'Anna B, Farren NJ, Hamilton JF, Pettersson JBC, Hallquist M, Antonsen S, Stenstrøm Y. Atmospheric Chemistry of 2-Amino-2-methyl-1-propanol: A Theoretical and Experimental Study of the OH-Initiated Degradation under Simulated Atmospheric Conditions. J Phys Chem A 2021; 125:7502-7519. [PMID: 34424704 PMCID: PMC8419843 DOI: 10.1021/acs.jpca.1c04898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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The OH-initiated
degradation of 2-amino-2-methyl-1-propanol [CH3C(NH2)(CH3)CH2OH, AMP] was
investigated in a large atmospheric simulation chamber, employing
time-resolved online high-resolution proton-transfer reaction-time-of-flight
mass spectrometry (PTR-ToF-MS) and chemical analysis of aerosol online
PTR-ToF-MS (CHARON-PTR-ToF-MS) instrumentation, and by theoretical
calculations based on M06-2X/aug-cc-pVTZ quantum chemistry results
and master equation modeling of the pivotal reaction steps. The quantum
chemistry calculations reproduce the experimental rate coefficient
of the AMP + OH reaction, aligning k(T) = 5.2 × 10–12 × exp (505/T) cm3 molecule–1 s–1 to the experimental value kexp,300K =
2.8 × 10–11 cm3 molecule–1 s–1. The theoretical calculations predict that
the AMP + OH reaction proceeds via hydrogen abstraction from the −CH3 groups (5–10%), −CH2– group,
(>70%) and −NH2 group (5–20%), whereas
hydrogen
abstraction from the −OH group can be disregarded under atmospheric
conditions. A detailed mechanism for atmospheric AMP degradation was
obtained as part of the theoretical study. The photo-oxidation experiments
show 2-amino-2-methylpropanal [CH3C(NH2)(CH3)CHO] as the major gas-phase product and propan-2-imine [(CH3)2C=NH], 2-iminopropanol [(CH3)(CH2OH)C=NH], acetamide [CH3C(O)NH2], formaldehyde (CH2O), and nitramine 2-methyl-2-(nitroamino)-1-propanol
[AMPNO2, CH3C(CH3)(NHNO2)CH2OH] as minor primary products; there is no experimental
evidence of nitrosamine formation. The branching in the initial H
abstraction by OH radicals was derived in analyses of the temporal
gas-phase product profiles to be BCH3/BCH2/BNH2 = 6:70:24. Secondary photo-oxidation products
and products resulting from particle and surface processing of the
primary gas-phase products were also observed and quantified. All
the photo-oxidation experiments were accompanied by extensive particle
formation that was initiated by the reaction of AMP with nitric acid
and that mainly consisted of this salt. Minor amounts of the gas-phase
photo-oxidation products, including AMPNO2, were detected
in the particles by CHARON-PTR-ToF-MS and GC×GC-NCD. Volatility
measurements of laboratory-generated AMP nitrate nanoparticles gave
ΔvapH = 80 ± 16 kJ mol–1 and an estimated vapor pressure of (1.3 ± 0.3)
× 10–5 Pa at 298 K. The atmospheric chemistry
of AMP is evaluated and a validated chemistry model for implementation
in dispersion models is presented.
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Affiliation(s)
- Wen Tan
- Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Liang Zhu
- Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Tomáš Mikoviny
- Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Claus J Nielsen
- Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Yizhen Tang
- Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Armin Wisthaler
- Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway.,Institute for Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria
| | - Philipp Eichler
- Institute for Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria
| | - Markus Müller
- Institute for Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria
| | - Barbara D'Anna
- Aix Marseille Université, CNRS, LCE, UMR 7376, 13331 Marseille, France
| | - Naomi J Farren
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York YO10 5DD, U.K
| | - Jacqueline F Hamilton
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York YO10 5DD, U.K
| | - Jan B C Pettersson
- Atmospheric Science, Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg, Sweden
| | - Mattias Hallquist
- Atmospheric Science, Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg, Sweden
| | - Simen Antonsen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway
| | - Yngve Stenstrøm
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway
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Lian X, Huang J, Zhang L, Liu C, Liu X, Wang L. Environmental Indicator for COVID-19 Non-Pharmaceutical Interventions. GEOPHYSICAL RESEARCH LETTERS 2021; 48:e2020GL090344. [PMID: 33612878 PMCID: PMC7883230 DOI: 10.1029/2020gl090344] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 05/07/2023]
Abstract
A novel coronavirus (COVID-19) has caused viral pneumonia worldwide, posing a major threat to international health. Our study reports that city lockdown is an effective way to reduce the number of new cases and the nitrogen dioxide (NO2) concentration can be used as an environmental lockdown indicator to evaluate the effectiveness of lockdown measures. The airborne NO2 concentration steeply decreased over the vast majority of COVID-19-hit areas since the lockdown. The total number of newly confirmed cases reached an inflection point about two weeks since the lockdown and could be reduced by about 50% within 30 days of the lockdown. The stricter lockdown will help newly confirmed cases to decline earlier and more rapidly, and at the same time, the reduction rate of NO2 concentration will increase. Our research results show that NO2 satellite observations can help decision makers effectively monitor and manage non-pharmaceutical interventions in the epidemic.
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Affiliation(s)
- Xinbo Lian
- Collaborative Innovation Center for Western Ecological SafetyCollege of Atmospheric SciencesLanzhou UniversityLanzhouChina
| | - Jianping Huang
- Collaborative Innovation Center for Western Ecological SafetyCollege of Atmospheric SciencesLanzhou UniversityLanzhouChina
- CAS Center for Excellence in Tibetan Plateau Earth SciencesBeijingChina
| | - Li Zhang
- Collaborative Innovation Center for Western Ecological SafetyCollege of Atmospheric SciencesLanzhou UniversityLanzhouChina
| | - Chuwei Liu
- Collaborative Innovation Center for Western Ecological SafetyCollege of Atmospheric SciencesLanzhou UniversityLanzhouChina
| | - Xiaoyue Liu
- Collaborative Innovation Center for Western Ecological SafetyCollege of Atmospheric SciencesLanzhou UniversityLanzhouChina
| | - Lina Wang
- Gansu Province Environmental Monitoring CenterLanzhouChina
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Chemical Characteristics of PM2.5 and Water-Soluble Organic Nitrogen in Yangzhou, China. ATMOSPHERE 2019. [DOI: 10.3390/atmos10040178] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Chemical characterization of fine atmospheric particles (PM2.5) is important for effective reduction of air pollution. This work analyzed PM2.5 samples collected in Yangzhou, China, during 2016. Ionic species, organic matter (OM), elemental carbon (EC), and trace metals were determined, and an Aerodyne soot-particle aerosol mass spectrometer (SP-AMS) was introduced to determine the OM mass, rather than only organic carbon mass. We found that inorganic ionic species was dominant (~52%), organics occupied about 1/4, while trace metals (~1%) and EC (~2.1%) contributed insignificantly to the total PM2.5 mass. Water-soluble OM appeared to link closely with secondary OM, while water-insoluble OM correlated well with primary OM. The PM2.5 concentrations were relatively low during summertime, while its compositions varied little among different months. Seasonal variations of water-soluble organic nitrogen (WSON) concentrations were not significant, while the mass contributions of WSON to total nitrogen were remarkably high during summer and autumn. WSON was found to associate better with secondary sources based on both correlation analyses and principle component analyses. Analyses of potential source contributions to WSON showed that regional emissions were dominant during autumn and winter, while the ocean became relatively important during spring and summer.
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