Production of Aerosol paRticle orgAnic Matter in ClOUds: chamber and laboratory studies, mechanisms, modelling and iNTegration

云中气溶胶颗粒有机物质的产生：室和实验室研究、机制、建模和集成

• 批准号: 407135662
• 负责人: Professor Dr. Hartmut Herrmann
• 金额: --
• 依托单位: Leibniz-Institut für Troposphärenforschung e.V. (TROPOS)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407135662?language=en
• 关键词: Production; Aerosol; paRticle; orgAnic; Matter

Recently, chemical processes in clouds have been suggested to contribute substantially to organic aerosol particle mass. Recent evidence from the HCCT-2010 field study and the CUMULUS chamber study suggest that this organic mass production can be substantial and depends on the concentration of available organic precursor compounds in the gas phase. However, considerable uncertainties exist, e.g. with regards to the nature of the resulting aerosol particles which might be metastable and loose at least part of their OM content during the cloud droplet evaporation. Hence, PARAMOUNT is aimed at the investigation of cloud processes which are able to process organic constituents and produce organic aerosol particle mass. The project will focus on the multiphase chemistry of very relevant polyfunctional precursors such as polyfunctional carbonyls and acids. With these precursors, a combination of aqueous-phase laboratory and CESAM chamber studies will be undertaken to examine the multiphase cloud processing. Firstly, aqueous-phase laboratory studies will lay the groundwork with regard to kinetics and mechanisms of the multiphase processing of the mentioned compounds. Then, the suggested CESAM chamber experiments, which are central in PARAMOUNT, will focus on studying the organic mass production by the chemical in-cloud processing of these compounds one by one, grouped or with mixtures with all of them. The planned chamber studies will use different seeds and oxidant precursors to examine the organic mass production under different environmental and diurnal conditions. The organic mass increase during the cloud episodes will be investigated. Besides the organic mass formation, the partitioning of organic compounds under cloud conditions should be studied to evaluate possible enrichments of organic carbonyl compounds observed during the cloud field campaign HCCT-2010. The organic aerosol fraction will be analysed on-line by two Aerosol Mass Spectrometer instruments and the processing of the interstitial gas phase and the phase partitioning will be investigated by PTR-MS and the use of a mini CVI (counter virtual impactor) followed by off-line analysis. Finally, the performed CESAM experiments are being modelled with the complex multiphase chemistry mechanism MCM/CAPRAM. The multiphase modelling will be performed to both validate the mechanism and support the interpretation of the chamber experiments. Overall, the proposed project PARAMOUNT will be a scientific breakthrough for understanding of in-cloud processes clarifying the role of clouds for atmospheric organic aerosol mass production.

最近，云中的化学过程被认为对有机气溶胶粒子质量有很大的贡献。HCCT-2010实地研究和CANULUS室研究的最新证据表明，这种有机物质的大量生产可能是巨大的，并取决于气相中现有有机前体化合物的浓度。然而，存在相当大的不确定性，例如，关于所产生的气溶胶颗粒的性质，其可能是亚稳态的，并且在云滴蒸发期间至少部分地释放其OM含量。因此，PARAMOUNT的目的是研究能够处理有机成分并产生有机气溶胶粒子质量的云过程。该项目将侧重于非常相关的多官能前体，如多官能羰基化合物和酸的多相化学。利用这些前体，将进行水相实验室和CESAM室研究的组合，以检查多相云处理。首先，水相实验室研究将为上述化合物的多相处理的动力学和机理奠定基础。然后，建议的CESAM室实验，这是PARAMOUNT的核心，将重点研究这些化合物逐一，分组或与所有这些化合物的混合物进行化学云处理的有机大规模生产。计划中的室内研究将使用不同的种子和氧化剂前体，以检查在不同的环境和昼夜条件下的有机物质的大量生产。将调查云事件期间的有机质量增加。除了有机物质的形成外，还应研究有机化合物在云条件下的分配情况，以评估HCCT-2010云场活动期间观测到的有机羰基化合物可能的富集情况。将通过两台气溶胶质谱仪对有机气溶胶部分进行在线分析，并通过PTR-MS和使用微型CVI（计数器虚拟撞击器）对间隙气相的处理和相划分进行研究，然后进行离线分析。最后，所进行的CESAM实验正在与复杂的多相化学机制MCM/CAPRAM建模。将进行多相建模，以验证机制并支持腔室实验的解释。总的来说，拟议的项目PARAMOUNT将是一个科学突破，有助于了解云内过程，澄清云在大气有机气溶胶大规模生产中的作用。