Are glyoxal and methylglyoxal critical to the formation of a missing fraction of SOA (Secondary Organic Aerosol)?: (Pho-SOA).

乙二醛和甲基乙二醛对于 SOA（二次有机气溶胶）缺失部分的形成至关重要吗？：（Pho-SOA）。

基本信息

批准号：
NE/H021108/1
负责人：
Andrew Rickard
金额：
$ 43.67万
依托单位：
University of Leeds
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2011
资助国家：
英国
起止时间：
2011 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FH021108%2F1
关键词：
glyoxal methylglyoxal critical formation missing

项目摘要

Atmospheric aerosols are ubiquitous in the Earth's atmosphere. They are made up of complex colloidal mixtures of liquid and solid particulate matter and understanding their chemical and physical properties is crucial in elucidating their environmental and health impacts. However, despite much scientific effort over the last decade, the true impact of aerosols on the Earth's atmosphere is yet to be elucidated owing to large uncertainties and lack of fundamental knowledge on their sources, composition (hence physical properties) and formation mechanisms. Recent experimental findings indicate organic aerosols (OA) are predominantly secondary in nature and can account for a significant fraction (10-70%) of total ambient atmospheric aerosol. However, current models significantly underestimate SOA (Secondary Organic Aerosol) production and their rate of formation. Accretion or oligomerization reactions of light weight volatiles such as glyoxal (GLY, CHOCHO) and methylglyoxal (MGLY, CH3COCHO), which have been shown to be a potentially important source of global SOA, have been proposed to justify such disagreement. The magnitude, type (reversible or irreversible) and mechanism of particle growth owing to alfa-dicarbonyls are still substantial questions. The aim of this project is to quantitatively demonstrate the hypothesis that heterogeneous uptake of GLY and MGLY in aerosols can explain a significant fraction of the missing SOA in models. To address this, the project will carry out an extensive series of outdoor chamber experiments (in the highly instrumented European Photoreactor, EUPHORE) that will address the main limitations of previous studies. The experimental work will be supported by detailed chamber simulations using the Master Chemical Mechanism (MCM15). GLY or MGLY will either be introduced directly into the chamber or generated in-situ by the reaction of OH + alkynes. The chamber experiments will be carried out in the presence (and absence) of natural solar radiation in EUPHORE in order to investigate whether heterogeneous reactive uptake of these dicarbonyl compounds and SOA growth is photochemically activated (photosensitized) and relative humidity dependent. The gas and aerosol phase evolution of the precursor and oxidation products, together with HOx radicals (OH + HO2) will be monitored using novel chemical ionisation reaction (time-of-flight and quadrupole) mass spectrometry (CIR-MS), Aerosol Time of Flight Mass Spectrometry (ATOFMS), Fourier Transform Ion Cyclotron resonance Mass Spectrometry (FT-ICR-MS), liquid chromatography-ion trap mass spectrometry (LC-MSn) and laser induced fluorescence (LIF). Model sensitivity simulations using the MCM coupled to a representation of absorptive gas-to-aerosol partitioning incorporating parameterisations from the findings of this study, will be carried out in order to investigate the atmospheric implications of SOA formation via heterogeneous uptake of dicarbonyl compounds for urban environment where aromatics compounds (significant sources of dicarbonyls) have been proposed as key urban SOA sources.

大气气溶胶在地球大气中无处不在。它们由液体和固体颗粒物的复杂胶体混合物组成，了解它们的化学和物理特性对于阐明其环境和健康影响至关重要。然而，尽管过去十年来，尽管大量的不确定性以及对其来源缺乏基本知识，组成（因此）和形成机制，但气溶胶对地球大气的真正影响尚未得到阐明。最近的实验发现表明，有机气溶胶（OA）本质上是次要的，并且可以占周环总气溶胶的显着部分（10-70％）。但是，当前的模型大大低估了SOA（二级有机气溶胶）的生产及其形成速率。已经提出，已经提出，已经提出，已经提出，已经提出，已经提出，已经提出，已经提出，已经提出，已证明这种分歧是合理的。由于Alfa-Dicarbonyls，大小，类型（可逆或不可逆）和颗粒生长的机制仍然是重大的问题。该项目的目的是定量证明以下假设：气溶胶中的gly和mgly的异质吸收可以解释模型中缺少SOA的很大一部分。为了解决这个问题，该项目将进行一系列室外室内实验（在高度仪器的欧洲光电反应器，Euphore中），该实验将解决以前研究的主要局限性。实验工作将通过使用主化学机制（MCM15）的详细室模拟来支持。 Gly或Mgly将直接引入室，或者通过OH +炔烃的反应产生的原位。腔室实验将在自然太阳辐射的存在（和不存在）的euphore中进行，以研究这些二烷基化合物的异质反应性吸收和SOA生长是否在光化学上激活（光敏化）和相对湿度依赖于光化和SOA生长。前体和氧化产物的气体和气溶胶相的演变以及HOX自由基（OH + HO2）将使用新型的化学电离反应（飞行时间和四极杆）质谱法（CIR-MS），气溶胶时间的质谱（CIR-MS），Aerosol时间的时间来监测飞行质谱法（ATOFM），傅立叶转化离子回旋共振质谱法（FT-ICR-MS），液相色谱 - 离子陷阱质谱法（LC-MSN）和激光诱导的荧光（LIF）。模型灵敏度模拟使用MCM耦合到吸收性气体到摩塞溶性分区的表示，将从本研究的发现中进行纳入参数化，以研究通过对城市环境的多种化合物的异质吸收SOA形成的大气形成的含义在芳香族化合物（大量的dicarbonyls的重要来源）中，已经提出了作为关键的城市SOA来源。

项目成果

期刊论文数量（7）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Online and offline mass spectrometric study of the impact of oxidation and ageing on glyoxal chemistry and uptake onto ammonium sulfate aerosols.

DOI：
10.1039/c3fd00051f
发表时间：
2013-12
期刊：
Faraday discussions
影响因子：
3.4
作者：
J. Hamilton;M. Baeza_Romero;E. Finessi;R. Andrew;Rickard;R. Healy;S. Peppe;T. J. Adams;S. M
通讯作者：
J. Hamilton;M. Baeza_Romero;E. Finessi;R. Andrew;Rickard;R. Healy;S. Peppe;T. J. Adams;S. M

Instrument inter-comparison of glyoxal, methyl glyoxal and NO<sub>2</sub> under simulated atmospheric conditions

乙二醛、甲基乙二醛与NO的仪器比对