Multi-faceted Studies on Highly Oxidized Organic Molecules MUSHROOM

高度氧化有机分子蘑菇的多方面研究

• 批准号: 2743356
• 金额: --
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2743356
• 关键词: Multi; faceted; Studies; Highly; Oxidized

"Highly oxidized organic molecules (HOMs) are a key set of compounds in the atmosphere that have attracted considerable recent attention.1 The low volatility of these compounds means that they have an important role in aerosol formation and growth with a consequent impact on air quality and climate.HOMs can be formed from simple organic species by a process known as auto-oxidation. For butane this could consist of the following chemistry. The initial radical formed (R), reacts with oxygen to give CH3CH2CH2CH2O2 (RO2). Now there is a competition between bimolecular reactions of RO2 with a range of atmospheric species (e.g. NO, NO2, HO2, RO2) and an internal abstraction to give a hydroperoxy radical CH3CHCH2CH2OOH. This process can then be repeated (addition of O2 to the carbon centre radical and internal abstraction) gradually introducing more functionality into the molecule and reducing the volatility.The proposers are well-placed to study this chemistry. The mechanism of auto-oxidation was developed within combustion chemistry and Seakins has studied such chemistry in dimethylether combustion, and brings expertise in laboratory kinetics of combustion and atmospheric chemistry.2-3 This component of the project will look at individual or small groups of elementary reactions. All three proposers are involved in the operation of the Highly Instrumented Reactor for Atmospheric Chemistry (HIRAC) which is another approach to obtaining kinetic information but with a complementary focus on the whole system rather than individual reactions. Heard is the PI on a NERC proposal looking at RO2 chemistry and Stone and Heard have particular expertise in monitoring RO2 species.4-5 The main focus of the project will be laboratory studies of gas phase species, but there will be scope to gain additional experience in modelling, calculations, fieldwork and aerosol chemistry depending on the interests of the student and how the project develops.1. Bianchi, F.; Kurten, T.; Riva, M.; Mohr, C.; Rissanen, M. P.; Roldin, P.; Berndt, T.; Crounse, J. D.; Wennberg, P. O.; Mentel, T. F.; Wildt, J.; Junninen, H.; Jokinen, T.; Kulmala, M.; Worsnop, D. R.; Thornton, J. A.; Donahue, N.; Kjaergaard, H. G.; Ehn, M., Highly oxygenated organic molecules (hom) from gas-phase autoxidation involving peroxy radicals: A key contributor to atmospheric aerosol. Chem. Rev. 2019, 119 (6), 3472-3509.2. Eskola, A. J.; Carr, S. A.; Shannon, R. J.; Wang, B.; Blitz, M. A.; Pilling, M. J.; Seakins, P. W.; Robertson, S. H., Analysis of the kinetics and yields of OH radical production from the CH3OCH2 + O2 reaction in the temperature range 195-650 K: An experimental and computational study. J. Phys. Chem. A 2014, 118 (34), 6773-6788.3. Glowacki, D. R.; Lockhart, J.; Blitz, M. A.; Klippenstein, S. J.; Pilling, M. J.; Robertson, S. H.; Seakins, P. W., Interception of excited vibrational quantum states by O2 in atmospheric association reactions. Science 2012, 337 (6098), 1066-1069.4. Onel, L.; Brennan, A.; Seakins, P. W.; Whalley, L.; Heard, D. E., A new method for atmospheric detection of the CH3O2 radical. Atmos. Meas. Tech. 2017, 10 (10), 3985-4000.5. Mir, Z. S.; Lewis, T. R.; Onel, L.; Blitz, M. A.; Seakins, P. W.; Stone, D., CH2OO criegee intermediate UV absorption cross-sections and kinetics of CH2OO + CH2OO and CH2OO + i as a function of pressure. PCCP 2020, 22 (17), 9448-9459."

“高度氧化的有机分子（HOM）是大气中一组重要的化合物，近年来引起了相当大的关注。1这些化合物的低挥发性意味着它们在气溶胶的形成和增长中起着重要作用，从而对空气质量和气候产生影响。HOM可以由简单的有机物种通过称为自动氧化的过程形成。对于丁烷，这可能包括以下化学物质。最初形成的自由基（R）与氧反应生成CH 3CH 2CH 2CH 2 O2（RO 2）。现在，RO 2与一系列大气物种（例如NO，NO2，HO 2，RO 2）的双分子反应和内部提取之间存在竞争，以产生氢过氧自由基CH 3CHCH 2CH 2 OOH。然后重复这个过程（将O2加入碳中心基团和内部提取），逐渐向分子中引入更多的官能团并降低挥发性。自动氧化的机理是在燃烧化学中发展起来的，Seakins研究了二甲醚燃烧中的这种化学，并带来了燃烧和大气化学实验室动力学方面的专业知识。所有三个提议者都参与了大气化学高级仪器反应堆的运行，这是获得动力学信息的另一种方法，但补充重点是整个系统，而不是个别反应。Heard是NERC关于RO 2化学的提案的PI，Stone和Heard在监测RO 2物种方面具有特殊的专业知识。4 -5该项目的主要重点将是气相物种的实验室研究，但根据学生的兴趣和项目的发展情况，将有机会获得建模，计算，现场工作和气溶胶化学方面的额外经验。比安奇;库尔滕，T.; Riva，M.;莫尔，C。; Rissanen，M. P的; Roldin，P.; Berndt，T.; Crounse，J. D.; Wennberg，P. O.; Mentel，T. F.地; Wildt，J.; Junninen，H.; Jokinen，T.; Kulmala，M.;沃斯诺普D。的R.;桑顿，J. A.; Donahue，N.; Kjaergaard，H. G.地; Ehn，M.，来自涉及过氧自由基的气相自氧化的高含氧有机分子（HOM）：大气气溶胶的关键贡献者。2019，119（6），3472-3509.2。Eskola，A. J.道：卡尔，S.一、香农河，巴西-地J.道：Wang，B.; Blitz，M.一、Pilling，M. J.道：Seakins，PW;罗伯逊，S。H、195-650 K温度范围内CH 3 OCH 2 + O2反应产生OH自由基的动力学和产率分析：实验和计算研究。J. Phys.Chem.A2014，118（34），6773-6788.3. Glowacki，D.的R.;洛克哈特，J。Blitz，M.一、Klippenstein，S. J.道：Pilling，M. J.道：罗伯逊，S。H.的; Seakins，P.W.，大气缔合反应中O2对激发振动量子态的拦截。Science 2012，337（6098），1066-1069.4.奥内尔湖; Brennan，A.; Seakins，PW;沃利，L.;听到了D E、大气中CH 3 O2自由基检测的新方法大气层。Meas. Tech. 2017，10（10），3985-4000.5. Mir，Z. S.的;刘易斯，T.的R.;奥内尔湖; Blitz，M.一、Seakins，PW;斯通，D.，CH_2OO分子筛中间紫外吸收截面和CH_2OO + CH_2OO和CH_2OO + i的动力学随压力的变化。PCCP 2020，22（17），9448-9459。"