105 results on '"Kang, Sungah"'
Search Results
2. Impact of HO2/RO2 ratio on highly oxygenated α-pinene photooxidation products and secondary organic aerosol formation potential.
- Author
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Baker, Yarê, Kang, Sungah, Wang, Hui, Wu, Rongrong, Xu, Jian, Zanders, Annika, He, Quanfu, Hohaus, Thorsten, Ziehm, Till, Geretti, Veronica, Bannan, Thomas J., O'Meara, Simon P., Voliotis, Aristeidis, Hallquist, Mattias, McFiggans, Gordon, Zorn, Sören R., Wahner, Andreas, and Mentel, Thomas F.
- Subjects
PINENE ,ORGANIC products ,AEROSOLS ,HYDROGEN peroxide ,PEROXY radicals ,PHOTOOXIDATION - Abstract
Highly oxygenated molecules (HOMs) from the atmospheric oxidation of biogenic volatile organic compounds are important contributors to secondary organic aerosol (SOA). Organic peroxy radicals (RO 2) and hydroperoxy radicals (HO 2) are key species influencing the HOM product distribution. In laboratory studies, experimental requirements often result in overemphasis on RO 2 cross-reactions compared to reactions of RO 2 with HO 2. We analyzed the photochemical formation of HOMs from α -pinene and their potential to contribute to SOA formation under high (≈1 /1) and low (≈1 /100) HO2/RO2 conditions. As HO2/RO2 > 1 is prevalent in the daytime atmosphere, sufficiently high HO2/RO2 is crucial to mimic atmospheric conditions and to prevent biases by low HO2/RO2 on the HOM product distribution and thus SOA yield. Experiments were performed under steady-state conditions in the new, continuously stirred tank reactor SAPHIR-STAR at Forschungszentrum Jülich. The HO2/RO2 ratio was increased by adding CO while keeping the OH concentration constant. We determined the HOM's SOA formation potential, considering its fraction remaining in the gas phase after seeding with (NH 4)2 SO 4 aerosol. An increase in HO2/RO2 led to a reduction in SOA formation potential, with the main driver being a ∼ 60 % reduction in HOM-accretion products. We also observed a shift in HOM-monomer functionalization from carbonyl to hydroperoxide groups. We determined a reduction of the HOM's SOA formation potential by ∼ 30 % at HO2/RO2 ≈1 /1 compared to HO2/RO2 ≈ 1/100. Particle-phase observations measured a similar decrease in SOA mass and yield. Our study shows that too low HO2/RO2 ratios compared to the atmosphere can lead to an overestimation of SOA yields. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Comparison of isoprene chemical mechanisms under atmospheric night-time conditions in chamber experiments: evidence of hydroperoxy aldehydes and epoxy products from NO3 oxidation
- Author
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Carlsson, Philip T. M., Vereecken, Luc, Novelli, Anna, Bernard, François, Brown, Steven S., Brownwood, Bellamy, Cho, Changmin, Crowley, John N., Dewald, Patrick, Edwards, Peter M., Friedrich, Nils, Fry, Juliane L., Hallquist, Mattias, Hantschke, Luisa, Hohaus, Thorsten, Kang, Sungah, Liebmann, Jonathan, Mayhew, Alfred W., Mentel, Thomas, Reimer, David, Rohrer, Franz, Shenolikar, Justin, Tillmann, Ralf, Tsiligiannis, Epameinondas, Wu, Rongrong, Wahner, Andreas, Kiendler-Scharr, Astrid, and Fuchs, Hendrik
- Subjects
Atmospheric Science ,ddc:550 ,Life Science - Abstract
The gas-phase reaction of isoprene with the nitrate radical (NO3) was investigated in experiments in the outdoor SAPHIR chamber under atmospherically relevant conditions specifically with respect to the chemical lifetime and fate of nitrato-organic peroxy radicals (RO2). Observations of organic products were compared to concentrations expected from different chemical mechanisms: (1) the Master Chemical Mechanism, which simplifies the NO3 isoprene chemistry by only considering one RO2 isomer; (2) the chemical mechanism derived from experiments in the Caltech chamber, which considers different RO2 isomers; and (3) the FZJ-NO3 isoprene mechanism derived from quantum chemical calculations, which in addition to the Caltech mechanism includes equilibrium reactions of RO2 isomers, unimolecular reactions of nitrate RO2 radicals and epoxidation reactions of nitrate alkoxy radicals. Measurements using mass spectrometer instruments give evidence that the new reactions pathways predicted by quantum chemical calculations play a role in the NO3 oxidation of isoprene. Hydroperoxy aldehyde (HPALD) species, which are specific to unimolecular reactions of nitrate RO2, were detected even in the presence of an OH scavenger, excluding the possibility that concurrent oxidation by hydroxyl radicals (OH) is responsible for their formation. In addition, ion signals at masses that can be attributed to epoxy compounds, which are specific to the epoxidation reaction of nitrate alkoxy radicals, were detected. Measurements of methyl vinyl ketone (MVK) and methacrolein (MACR) concentrations confirm that the decomposition of nitrate alkoxy radicals implemented in the Caltech mechanism cannot compete with the ring-closure reactions predicted by quantum chemical calculations. The validity of the FZJ-NO3 isoprene mechanism is further supported by a good agreement between measured and simulated hydroxyl radical (OH) reactivity. Nevertheless, the FZJ-NO3 isoprene mechanism needs further investigations with respect to the absolute importance of unimolecular reactions of nitrate RO2 and epoxidation reactions of nitrate alkoxy radicals. Absolute concentrations of specific organic nitrates such as nitrate hydroperoxides would be required to experimentally determine product yields and branching ratios of reactions but could not be measured in the chamber experiments due to the lack of calibration standards for these compounds. The temporal evolution of mass traces attributed to product species such as nitrate hydroperoxides, nitrate carbonyl and nitrate alcohols as well as hydroperoxy aldehydes observed by the mass spectrometer instruments demonstrates that further oxidation by the nitrate radical and ozone at atmospheric concentrations is small on the timescale of one night (12 h) for typical oxidant concentrations. However, oxidation by hydroxyl radicals present at night and potentially also produced from the decomposition of nitrate alkoxy radicals can contribute to their nocturnal chemical loss.
- Published
- 2023
4. Secondary organic aerosol reduced by mixture of atmospheric vapours
- Author
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McFiggans, Gordon, Mentel, Thomas F., Wildt, Jürgen, Pullinen, Iida, Kang, Sungah, Kleist, Einhard, Schmitt, Sebastian, Springer, Monika, Tillmann, Ralf, Wu, Cheng, Zhao, Defeng, Hallquist, Mattias, Faxon, Cameron, Le Breton, Michael, Hallquist, Åsa M., Simpson, David, Bergström, Robert, Jenkin, Michael E., Ehn, Mikael, Thornton, Joel A., Alfarra, M. Rami, Bannan, Thomas J., Percival, Carl J., Priestley, Michael, Topping, David, and Kiendler-Scharr, Astrid
- Published
- 2019
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5. Supplementary material to "Application of fuzzy c-means clustering for analysis of chemical ionization mass spectra: insights into the gas-phase chemistry of NO3-initiated oxidation of isoprene"
- Author
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Wu, Rongrong, primary, Zorn, Sören, additional, Kang, Sungah, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, and Mentel, Thomas F., additional
- Published
- 2023
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6. Application of fuzzy c-means clustering for analysis of chemical ionization mass spectra: insights into the gas-phase chemistry of NO3-initiated oxidation of isoprene
- Author
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Wu, Rongrong, primary, Zorn, Sören, additional, Kang, Sungah, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, and Mentel, Thomas F., additional
- Published
- 2023
- Full Text
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7. Comparison of isoprene chemical mechanisms under atmospheric night-time conditions in chamber experiments : Evidence of hydroperoxy aldehydes and epoxy products from NO3 oxidation
- Author
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Carlsson, Philip T.M., Vereecken, Luc, Novelli, Anna, Bernard, François, Brown, Steven S., Brownwood, Bellamy, Cho, Changmin, Crowley, John N., Dewald, Patrick, Edwards, Peter M., Friedrich, Nils, Fry, Juliane L., Hallquist, Mattias, Hantschke, Luisa, Hohaus, Thorsten, Kang, Sungah, Liebmann, Jonathan, Mayhew, Alfred W., Mentel, Thomas, Reimer, David, Rohrer, Franz, Shenolikar, Justin, Tillmann, Ralf, Tsiligiannis, Epameinondas, Wu, Rongrong, Wahner, Andreas, Kiendler-Scharr, Astrid, Fuchs, Hendrik, Carlsson, Philip T.M., Vereecken, Luc, Novelli, Anna, Bernard, François, Brown, Steven S., Brownwood, Bellamy, Cho, Changmin, Crowley, John N., Dewald, Patrick, Edwards, Peter M., Friedrich, Nils, Fry, Juliane L., Hallquist, Mattias, Hantschke, Luisa, Hohaus, Thorsten, Kang, Sungah, Liebmann, Jonathan, Mayhew, Alfred W., Mentel, Thomas, Reimer, David, Rohrer, Franz, Shenolikar, Justin, Tillmann, Ralf, Tsiligiannis, Epameinondas, Wu, Rongrong, Wahner, Andreas, Kiendler-Scharr, Astrid, and Fuchs, Hendrik
- Abstract
The gas-phase reaction of isoprene with the nitrate radical (NO3) was investigated in experiments in the outdoor SAPHIR chamber under atmospherically relevant conditions specifically with respect to the chemical lifetime and fate of nitrato-organic peroxy radicals (RO2). Observations of organic products were compared to concentrations expected from different chemical mechanisms: (1) the Master Chemical Mechanism, which simplifies the NO3 isoprene chemistry by only considering one RO2 isomer; (2) the chemical mechanism derived from experiments in the Caltech chamber, which considers different RO2 isomers; and (3) the FZJ-NO3 isoprene mechanism derived from quantum chemical calculations, which in addition to the Caltech mechanism includes equilibrium reactions of RO2 isomers, unimolecular reactions of nitrate RO2 radicals and epoxidation reactions of nitrate alkoxy radicals. Measurements using mass spectrometer instruments give evidence that the new reactions pathways predicted by quantum chemical calculations play a role in the NO3 oxidation of isoprene. Hydroperoxy aldehyde (HPALD) species, which are specific to unimolecular reactions of nitrate RO2, were detected even in the presence of an OH scavenger, excluding the possibility that concurrent oxidation by hydroxyl radicals (OH) is responsible for their formation. In addition, ion signals at masses that can be attributed to epoxy compounds, which are specific to the epoxidation reaction of nitrate alkoxy radicals, were detected. Measurements of methyl vinyl ketone (MVK) and methacrolein (MACR) concentrations confirm that the decomposition of nitrate alkoxy radicals implemented in the Caltech mechanism cannot compete with the ring-closure reactions predicted by quantum chemical calculations. The validity of the FZJ-NO3 isoprene mechanism is further supported by a good agreement between measured and simulated hydroxyl radical (OH) reactivity. Nevertheless, the FZJ-NO3 isoprene mechanism needs further investigations
- Published
- 2023
8. Impact of HO2/RO2 ratio on highly oxygenated α-pinene photooxidation products and secondary organic aerosol formation potential.
- Author
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Baker, Yarê, Kang, Sungah, Wang, Hui, Wu, Rongrong, Xu, Jian, Zanders, Annika, He, Quanfu, Hohaus, Thorsten, Ziehm, Till, Geretti, Veronica, Bannan, Thomas J., O'Meara, Simon P., Voliotis, Aristeidis, Hallquist, Mattias, McFiggans, Gordon, Zorn, Sören R., Wahner, Andreas, and Mentel, Thomas
- Subjects
PINENE ,ORGANIC products ,AEROSOLS ,HYDROGEN peroxide ,PEROXY radicals ,PHOTOOXIDATION - Abstract
Highly oxygenated molecules (HOM) from the atmospheric oxidation of biogenic volatile organic compounds are important contributors to secondary organic aerosol (SOA). Organic peroxy radicals (RO
2 ) and hydroperoxy radicals (HO2 ) are key species influencing the HOM product distribution. In laboratory studies experimental requirements often result in overemphasis of RO2 cross-reactions compared to reactions of RO2 with HO2 . We analyzed the photochemical formation of HOMs from α-pinene and their potential to contribute to SOA formation under high (≈1/1) and low (≈1/100) HO2 /RO2 conditions. As HO2 /RO2 > 1 is prevalent in the daytime atmosphere, sufficiently high HO2 /RO2 is crucial to mimic atmospheric conditions and to prevent biases by low HO2 /RO2 on the HOM product distribution and thus SOA yield. Experiments were performed under steady-state conditions in the new, continuously stirred tank reactor SAPHIR-STAR at Forschungszentrum Jülich. The HO2 /RO2 ratio was increased by adding CO, while keeping the OH concentration constant. We determined the HOM's SOA formation potential, considering their fraction remaining in the gas phase after seeding with (NH4 )2 SO4 aerosol. Increase of HO2 /RO2 led to a reduction in SOA formation potential, with the main driver being a ≈60 % reduction in HOM-accretion products. We also observed a shift in HOM-monomer functionalization from carbonyl to hydroperoxide groups. We determined a reduction of the HOM's SOA formation potential by ≈30 % at HO2 /RO2 ≈1/1. Particle phase observations measured an about according decrease in SOA mass and yield. Our study showed that too low HO2 /RO2 ratios compared to the atmosphere can lead to an overestimation of SOA yields. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
9. Supplementary material to "Formation of highly oxygenated organic molecules from the oxidation of limonene by OH radical: significant contribution of H-abstraction pathway"
- Author
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Luo, Hao, primary, Vereecken, Luc, additional, Shen, Hongru, additional, Kang, Sungah, additional, Pullinen, Iida, additional, Hallquist, Mattias, additional, Fuchs, Hendrik, additional, Wahner, Andreas, additional, Kiendler-Scharr, Astrid, additional, Mentel, Thomas F., additional, and Zhao, Defeng, additional
- Published
- 2022
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10. Formation of highly oxygenated organic molecules from the oxidation of limonene by OH radical: significant contribution of H-abstraction pathway
- Author
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Luo, Hao, primary, Vereecken, Luc, additional, Shen, Hongru, additional, Kang, Sungah, additional, Pullinen, Iida, additional, Hallquist, Mattias, additional, Fuchs, Hendrik, additional, Wahner, Andreas, additional, Kiendler-Scharr, Astrid, additional, Mentel, Thomas F., additional, and Zhao, Defeng, additional
- Published
- 2022
- Full Text
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11. Unexpected significance of a minor reaction pathway in daytime formation of biogenic highly oxygenated organic compounds
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Shen, Hongru, primary, Vereecken, Luc, additional, Kang, Sungah, additional, Pullinen, Iida, additional, Fuchs, Hendrik, additional, Zhao, Defeng, additional, and Mentel, Thomas F., additional
- Published
- 2022
- Full Text
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12. Identification of highly oxygenated organic molecules and their role in aerosol formation in the reaction of limonene with nitrate radical
- Author
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Guo, Yindong, primary, Shen, Hongru, additional, Pullinen, Iida, additional, Luo, Hao, additional, Kang, Sungah, additional, Vereecken, Luc, additional, Fuchs, Hendrik, additional, Hallquist, Mattias, additional, Acir, Ismail-Hakki, additional, Tillmann, Ralf, additional, Rohrer, Franz, additional, Wildt, Jürgen, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Zhao, Defeng, additional, and Mentel, Thomas F., additional
- Published
- 2022
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- View/download PDF
13. Application of fuzzy c-means clustering for analysis of chemical ionization mass spectra: insights into the gas-phase chemistry of NO3-initiated oxidation of isoprene.
- Author
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Wu, Rongrong, Zorn, Sören, Kang, Sungah, Kiendler-Scharr, Astrid, Wahner, Andreas, and Mentel, Thomas F.
- Subjects
ANALYTICAL chemistry ,CHEMICAL ionization mass spectrometry ,MASS spectrometry ,CHEMICAL processes ,CLUSTER analysis (Statistics) ,CHEMICAL properties - Abstract
Oxidation of volatile organic compounds (VOCs) can lead to the formation of secondary organic aerosol, a significant component of atmospheric fine particles, which can affect air quality, human health, and climate change. However, current understanding of the formation mechanism of SOA is still incomplete, which is not only due to the complexity of the chemistry, but also relates to analytical challenges in SOA precursor detection and quantification. Recent instrumental advances, especially the developments of high-resolution time-of-flight chemical ionization mass spectrometry (CIMS), greatly enhanced the capability to detect low- and extremely low-volatility organic molecules (L/ELVOCs). Although detection and characterization of low volatility vapors largely improved our understanding of SOA formation, analyzing and interpreting complex mass spectrometric data remains a challenging task. This necessitates the use of dimension-reduction techniques to simplify mass spectrometric data with the purpose of extracting chemical and kinetic information of the investigated system. Here we present an approach by using fuzzy c -means clustering (FCM) to analyze CIMS data from chamber experiments aiming to investigate the gas-phase chemistry of nitrate radical initiated oxidation of isoprene. The performance of FCM was evaluated and validated. By applying FCM various oxidation products were classified into different groups according to their chemical and kinetic properties, and the common patterns of their time series were identified, which gave insights into the chemistry of the system investigated. The chemical properties are characterized by elemental ratios and average carbon oxidation state, and the kinetic behaviors are parameterized with generation number and effective rate coefficient (describing the average reactivity of a species) by using the gamma kinetic parameterization model. In addition, the fuzziness of FCM algorithm provides a possibility to separate isomers or different chemical processes species are involved in, which could be useful for mechanism development. Overall FCM is a well applicable technique to simplify complex mass spectrometric data, and the chemical and kinetic properties derived from clustering can be utilized to understand the reaction system of interest. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
14. Formation of highly oxygenated organic molecules from the oxidation of limonene by OH radical: significant contribution of H-abstraction pathway.
- Author
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Luo, Hao, Vereecken, Luc, Shen, Hongru, Kang, Sungah, Pullinen, Iida, Hallquist, Mattias, Fuchs, Hendrik, Wahner, Andreas, Kiendler-Scharr, Astrid, Mentel, Thomas F., and Zhao, Defeng
- Subjects
LIMONENE ,RADICALS (Chemistry) ,PEROXY radicals ,CHEMICAL ionization mass spectrometry ,MOLECULES ,STRUCTURE-activity relationships ,NITRATE reductase - Abstract
Highly oxygenated organic molecules (HOMs) play a pivotal role in the formation of secondary organic aerosol (SOA). Therefore, the distribution and yields of HOMs are fundamental to understand their fate and chemical evolution in the atmosphere, and it is conducive to ultimately assess the impact of SOA on air quality and climate change. In this study, gas-phase HOMs formed from the reaction of limonene with OH radicals in photooxidation were investigated with SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction chamber), using a time-of-flight chemical ionization mass spectrometer with nitrate reagent ion (NO 3- -CIMS). A large number of HOMs, including monomers (C 9–10) and dimers (C 17–20), were detected and classified into various families. Both closed-shell products and open-shell peroxy radicals (RO 2) were identified under low NO (0.06–0.1 ppb) and high NO conditions (17 ppb). C 10 monomers are the most abundant HOM products and account for over 80 % total HOMs. Closed-shell C 10 monomers were formed from a two peroxy radical family, C 10 H 15 O x⚫ (x=6 –15) and C 10 H 17 O x⚫ (x=6 –15), and their respective termination reactions with NO, RO 2 , and HO 2. While C 10 H 17 O x⚫ is likely formed by OH addition to C 10 H 16 , the dominant initial step of limonene plus OH, C 10 H 15 O x⚫ , is likely formed via H abstraction by OH. C 10 H 15 O x⚫ and related products contributed 41 % and 42 % of C 10 HOMs at low and high NO, demonstrating that the H-abstraction pathways play a significant role in HOM formation in the reaction of limonene plus OH. Combining theoretical kinetic calculations, structure–activity relationships (SARs), data from the literature, and the observed RO 2 intensities, we proposed tentative mechanisms of HOM formation from both pathways. We further estimated the molar yields of HOMs to be 1.97-1.06+2.52 % and 0.29-0.16+0.38 % at low and high NO, respectively. Our study highlights the importance of H abstraction by OH and provides the yield and tentative pathways in the OH oxidation of limonene to simulate the HOM formation and assess the role of HOMs in SOA formation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
15. Comparison of isoprene chemical mechanisms at atmospheric night-time conditions in chamber experiments: Evidence of hydroperoxy aldehydes and epoxy products from NO3 oxidation
- Author
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Carlsson, Philip T. M., primary, Vereecken, Luc, additional, Novelli, Anna, additional, Bernard, François, additional, Brown, Steven S., additional, Brownwood, Bellamy, additional, Cho, Changmin, additional, Crowley, John N., additional, Dewald, Patrick, additional, Edwards, Peter M., additional, Friedrich, Nils, additional, Fry, Juliane L., additional, Hallquist, Mattias, additional, Hantschke, Luisa, additional, Hohaus, Thorsten, additional, Kang, Sungah, additional, Liebmann, Jonathan, additional, Mayhew, Alfred W., additional, Mentel, Thomas, additional, Reimer, David, additional, Rohrer, Franz, additional, Shenolikar, Justin, additional, Tillmann, Ralf, additional, Tsiligiannis, Epameinondas, additional, Wu, Rongrong, additional, Wahner, Andreas, additional, Kiendler-Scharr, Astrid, additional, and Fuchs, Hendrik, additional
- Published
- 2022
- Full Text
- View/download PDF
16. Unexpected significance of a minor reaction pathway in daytime formation of biogenic highly oxygenated organic compounds
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Shen, Hongru, Vereecken, Luc, Kang, Sungah, Pullinen, Iida, Fuchs, Hendrik, Zhao, Defeng, Mentel, Thomas F., Shen, Hongru, Vereecken, Luc, Kang, Sungah, Pullinen, Iida, Fuchs, Hendrik, Zhao, Defeng, and Mentel, Thomas F.
- Abstract
Secondary organic aerosol (SOA), formed by oxidation of volatile organic compounds, substantially influence air quality and climate. Highly oxygenated organic molecules (HOMs), particularly those formed from biogenic monoterpenes, contribute a large fraction of SOA. During daytime, hydroxyl radicals initiate monoterpene oxidation, mainly by hydroxyl addition to monoterpene double bonds. Naturally, related HOM formation mechanisms should be induced by that reaction route, too. However, for a-pinene, the most abundant atmospheric monoterpene, we find a previously unidentified competitive pathway under atmospherically relevant conditions: HOM formation is predominately induced via hydrogen abstraction by hydroxyl radicals, a generally minor reaction pathway. We show by observations and theoretical calculations that hydrogen abstraction followed by formation and rearrangement of alkoxy radicals is a prerequisite for fast daytime HOM formation. Our analysis provides an accurate mechanism and yield, demonstrating that minor reaction pathways can become major, here for SOA formation and growth and related impacts on air quality and climate.
- Published
- 2022
17. A Four Carbon Organonitrate as a Significant Product of Secondary Isoprene Chemistry
- Author
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Tsiligiannis, Epameinondas, Wu, Rongrong, Lee, Ben H., Salvador, Christian Mark, Priestley, Michael, Carlsson, Philip T.M., Kang, Sungah, Novelli, Anna, Vereecken, Luc, Fuchs, Hendrik, Mayhew, Alfred W., Hamilton, Jacqueline F., Edwards, Peter M., Fry, Juliane L., Brownwood, Bellamy, Brown, Steven S., Wild, Robert J., Bannan, Thomas J., Coe, Hugh, Allan, James, Surratt, Jason D., Bacak, Asan, Artaxo, Paul, Percival, Carl, Guo, Song, Hu, Min, Wang, Tao, Mentel, Thomas F., Thornton, Joel A., Hallquist, Mattias, Tsiligiannis, Epameinondas, Wu, Rongrong, Lee, Ben H., Salvador, Christian Mark, Priestley, Michael, Carlsson, Philip T.M., Kang, Sungah, Novelli, Anna, Vereecken, Luc, Fuchs, Hendrik, Mayhew, Alfred W., Hamilton, Jacqueline F., Edwards, Peter M., Fry, Juliane L., Brownwood, Bellamy, Brown, Steven S., Wild, Robert J., Bannan, Thomas J., Coe, Hugh, Allan, James, Surratt, Jason D., Bacak, Asan, Artaxo, Paul, Percival, Carl, Guo, Song, Hu, Min, Wang, Tao, Mentel, Thomas F., Thornton, Joel A., and Hallquist, Mattias
- Abstract
Oxidation of isoprene by nitrate radicals (NO3) or by hydroxyl radicals (OH) under high NOx conditions forms a substantial amount of organonitrates (ONs). ONs impact NOx concentrations and consequently ozone formation while also contributing to secondary organic aerosol. Here we show that the ONs with the chemical formula C4H7NO5 are a significant fraction of isoprene-derived ONs, based on chamber experiments and ambient measurements from different sites around the globe. From chamber experiments we found that C4H7NO5 isomers contribute 5%–17% of all measured ONs formed during nighttime and constitute more than 40% of the measured ONs after further daytime oxidation. In ambient measurements C4H7NO5 isomers usually dominate both nighttime and daytime, implying a long residence time compared to C5 ONs which are removed more rapidly. We propose potential nighttime sources and secondary formation pathways, and test them using a box model with an updated isoprene oxidation scheme.
- Published
- 2022
18. A Four Carbon Organonitrate as a Significant Product of Secondary Isoprene Chemistry
- Author
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Tsiligiannis, Epameinondas, primary, Wu, Rongrong, additional, Lee, Ben H., additional, Salvador, Christian Mark, additional, Priestley, Michael, additional, Carlsson, Philip T. M., additional, Kang, Sungah, additional, Novelli, Anna, additional, Vereecken, Luc, additional, Fuchs, Hendrik, additional, Mayhew, Alfred W., additional, Hamilton, Jacqueline F., additional, Edwards, Peter M., additional, Fry, Juliane L., additional, Brownwood, Bellamy, additional, Brown, Steven S., additional, Wild, Robert J., additional, Bannan, Thomas J., additional, Coe, Hugh, additional, Allan, James, additional, Surratt, Jason D., additional, Bacak, Asan, additional, Artaxo, Paul, additional, Percival, Carl, additional, Guo, Song, additional, Hu, Min, additional, Wang, Tao, additional, Mentel, Thomas F., additional, Thornton, Joel A., additional, and Hallquist, Mattias, additional
- Published
- 2022
- Full Text
- View/download PDF
19. Supplementary material to "Identification of highly oxygenated organic molecules and their role in aerosol formation in the reaction of limonene with nitrate radical"
- Author
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Guo, Yindong, primary, Shen, Hongru, additional, Pullinen, Iida, additional, Luo, Hao, additional, Kang, Sungah, additional, Vereecken, Luc, additional, Fuchs, Hendrik, additional, Hallquist, Mattias, additional, Acir, Ismail-Hakki, additional, Tillmann, Ralf, additional, Rohrer, Franz, additional, Wildt, Jürgen, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Zhao, Defeng, additional, and Mentel, Thomas F., additional
- Published
- 2022
- Full Text
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20. Highly oxygenated organic molecule (HOM) formation in the isoprene oxidation by NO3 radical
- Author
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Zhao, Defeng, Pullinen, Iida, Kiendler-Scharr, Astrid, Wahner, Andreas, Kang, Sungah, Vereecken, Luc, Mentel, Thomas F., Fuchs, Hendrik, Schrade, Stephanie, Wu, Rongrong, Acir, Ismail-Hakki, Tillmann, Ralf, Rohrer, Franz, Wildt, Jürgen, and Guo, Yindong
- Subjects
ddc:550 - Abstract
Highly oxygenated organic molecules (HOM) are found to play an important role in the formation and growth of secondary organic aerosol (SOA). SOA is an important type of aerosol with significant impact on air quality and climate. Compared with the oxidation of volatile organic compounds by ozone (O3) and hydroxyl radical (OH), HOM formation in the oxidation by nitrate radical (NO3), an important oxidant at nighttime and dawn, has received less attention. In this study, HOM formation in the reaction of isoprene with NO3 was investigated in the SAPHIR chamber (Simulation of Atmospheric PHotochemistry In a large Reaction chamber). A large number of HOM, including monomers (C5), dimers (C10), and trimers (C15), both closed-shell compounds and open-shell peroxy radicals (RO2), were identified and were classified into various series according to their formula. Their formation pathways were proposed based on the peroxy radicals observed and known mechanisms in the literature, which were further constrained by the time profiles of HOM after sequential isoprene addition to differentiate first- and second-generation products. HOM monomers containing one to three N atoms (1–3N-monomers) were formed, starting with NO3 addition to carbon double bond, forming peroxy radicals, followed by autoxidation. 1N-monomers were formed by both the direct reaction of NO3 with isoprene and of NO3 with first-generation products. 2N-monomers (e.g., C5H8N2On(n=7–13), C5H10N2On(n=8–14)) were likely the termination products of C5H9N2On⚫, which was formed by the addition of NO3 to C5-hydroxynitrate (C5H9NO4), a first-generation product containing one carbon double bond. 2N-monomers, which were second-generation products, dominated in monomers and accounted for ∼34 % of all HOM, indicating the important role of second-generation oxidation in HOM formation in the isoprene + NO3 reaction under our experimental conditions. H shift of alkoxy radicals to form peroxy radicals and subsequent autoxidation (“alkoxy–peroxy” pathway) was found to be an important pathway of HOM formation. HOM dimers were mostly formed by the accretion reaction of various HOM monomer RO2 and via the termination reactions of dimer RO2 formed by further reaction of closed-shell dimers with NO3 and possibly by the reaction of C5–RO2 with isoprene. HOM trimers were likely formed by the accretion reaction of dimer RO2 with monomer RO2. The concentrations of different HOM showed distinct time profiles during the reaction, which was linked to their formation pathway. HOM concentrations either showed a typical time profile of first-generation products, second-generation products, or a combination of both, indicating multiple formation pathways and/or multiple isomers. Total HOM molar yield was estimated to be 1.2 %-0.7%+1.3%, which corresponded to a SOA yield of ∼3.6 % assuming the molecular weight of C5H9NO6 as the lower limit. This yield suggests that HOM may contribute a significant fraction to SOA yield in the reaction of isoprene with NO3.
- Published
- 2021
21. Highly Oxygenated Organic Nitrates Formed from NO3 Radical-Initiated Oxidation of β-Pinene
- Author
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Shen, Hongru, primary, Zhao, Defeng, additional, Pullinen, Iida, additional, Kang, Sungah, additional, Vereecken, Luc, additional, Fuchs, Hendrik, additional, Acir, Ismail-Hakki, additional, Tillmann, Ralf, additional, Rohrer, Franz, additional, Wildt, Jürgen, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, and Mentel, Thomas F., additional
- Published
- 2021
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22. Chemical characterisation of benzene oxidation products under high- And low-NOx conditions using chemical ionisation mass spectrometry
- Author
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Priestley, Michael, Bannan, Thomas J., Breton, Michael, Worrall, Stephen D., Kang, Sungah, Pullinen, Iida, Schmitt, Sebastian, Tillmann, Ralf, Kleist, Einhard, Zhao, Defeng, Wildt, Jürgen, Garmash, Olga, Mehra, Archit, Bacak, Asan, Shallcross, Dudley E., Kiendler-Scharr, Astrid, Hallquist, Åsa M., Ehn, Mikael, Coe, Hugh, Percival, Carl J., Hallquist, Mattias, Mentel, Thomas F., McFiggans, Gordon, INAR Physics, and Institute for Atmospheric and Earth System Research (INAR)
- Subjects
ddc:550 ,114 Physical sciences - Abstract
Aromatic hydrocarbons are a class of volatile organic compounds associated with anthropogenic activity and make up a significant fraction of urban volatile organic compound (VOC) emissions that contribute to the formation of secondary organic aerosol (SOA). Benzene is one of the most abundant species emitted from vehicles, biomass burning and industry. An iodide time-of-flight chemical ionisation mass spectrometer (ToF-CIMS) and nitrate ToF-CIMS were deployed at the Jülich Plant Atmosphere Chamber as part of a series of experiments examining benzene oxidation by OH under high- and low-NOx conditions, where a range of organic oxidation products were detected. The nitrate scheme detects many oxidation products with high masses, ranging from intermediate volatile organic compounds (IVOCs) to extremely low volatile organic compounds (ELVOCs), including C12 dimers. In comparison, very few species with C≥6 and O≥8 were detected with the iodide scheme, which detected many more IVOCs and semi-volatile organic compounds (SVOCs) but very few ELVOCs and low volatile organic compounds (LVOCs). A total of 132 and 195 CHO and CHON oxidation products are detected by the iodide ToF-CIMS in the low- and high-NOx experiments respectively. Ring-breaking products make up the dominant fraction of detected signal and 21 and 26 of the products listed in the Master Chemical Mechanism (MCM) were detected. The time series of highly oxidised (O≥6) and ring-retaining oxidation products (C6 and double-bond equivalent = 4) equilibrate quickly, characterised by a square form profile, compared to MCM and ring-breaking products which increase throughout oxidation, exhibiting sawtooth profiles. Under low-NOx conditions, all CHO formulae attributed to radical termination reactions of first-generation benzene products, and first-generation auto-oxidation products are observed. Several N-containing species that are either first-generation benzene products or first-generation auto-oxidation products are also observed under high-NOx conditions. Hierarchical cluster analysis finds four clusters, of which two describe photo-oxidation. Cluster 2 shows a negative dependency on the NO2/NOx ratio, indicating it is sensitive to NO concentration and thus likely to contain NO addition products and alkoxy-derived termination products. This cluster has the highest average carbon oxidation state (OSC‾) and the lowest average carbon number. Where nitrogen is present in a cluster member of cluster 2, the oxygen number is even, as expected for alkoxy-derived products. In contrast, cluster 1 shows no dependency on the NO2/NOx ratio and so is likely to contain more NO2 addition and peroxy-derived termination products. This cluster contains fewer fragmented species, as the average carbon number is higher and OSC‾ lower than cluster 2, and more species with an odd number of oxygen atoms. This suggests that clustering of time series which have features pertaining to distinct chemical regimes, for example, NO2/NOx perturbations, coupled with a priori knowledge, can provide insight into identification of potential functionality.
- Published
- 2021
23. Molecular composition and volatility of multi-generation products formed from isoprene oxidation by nitrate radical
- Author
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Wu, Rongrong, primary, Vereecken, Luc, additional, Tsiligiannis, Epameinondas, additional, Kang, Sungah, additional, Albrecht, Sascha R., additional, Hantschke, Luisa, additional, Zhao, Defeng, additional, Novelli, Anna, additional, Fuchs, Hendrik, additional, Tillmann, Ralf, additional, Hohaus, Thorsten, additional, Carlsson, Philip T. M., additional, Shenolikar, Justin, additional, Bernard, François, additional, Crowley, John N., additional, Fry, Juliane L., additional, Brownwood, Bellamy, additional, Thornton, Joel A., additional, Brown, Steven S., additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Hallquist, Mattias, additional, and Mentel, Thomas F., additional
- Published
- 2021
- Full Text
- View/download PDF
24. Highly oxygenated organic molecule (HOM) formation in the isoprene oxidation by NO<sub>3</sub> radical
- Author
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Zhao, Defeng, primary, Pullinen, Iida, additional, Fuchs, Hendrik, additional, Schrade, Stephanie, additional, Wu, Rongrong, additional, Acir, Ismail-Hakki, additional, Tillmann, Ralf, additional, Rohrer, Franz, additional, Wildt, Jürgen, additional, Guo, Yindong, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Kang, Sungah, additional, Vereecken, Luc, additional, and Mentel, Thomas F., additional
- Published
- 2021
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25. Comparison of isoprene chemical mechanisms at atmospheric night-time conditions in chamber experiments: Evidence of hydroperoxy aldehydes and epoxy products from NO3 oxidation.
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Carlsson, Philip T. M., Vereecken, Luc, Novelli, Anna, Bernard, François, Brown, Steven S., Brownwood, Bellamy, Cho, Changmin, Crowley, John N., Dewald, Patrick, Edwards, Peter M., Friedrich, Nils, Fry, Juliane L., Hallquist, Mattias, Hantschke, Luisa, Hohaus, Thorsten, Kang, Sungah, Liebmann, Jonathan, Mayhew, Alfred W., Mentel, Thomas, and Reimer, David
- Subjects
ISOPRENE ,OXIDATION ,ALDEHYDES ,EPOXY resins ,NITRATES - Abstract
The gas-phase reaction of isoprene with the nitrate radical (NO
3 ) was investigated in experiments in the outdoor SAPHIR chamber at atmospherically relevant conditions specifically with respect to the chemical lifetime and fate of nitrato-organic peroxy radicals (RO2 ). Observations of organic products were compared to concentrations expected from different chemical mechanisms: (1) The Master Chemical Mechanism, which simplifies the NO3 isoprene chemistry by only considering one RO2 conformer. (2) The chemical mechanism derived from experiments in the CalTech chamber, which considers different RO2 conformers. (3) The FZJ-NO3 isoprene mechanism derived from quantum chemical calculations, which in addition to the CalTech mechanism includes equilibrium reactions of RO2 conformers, unimolecular reactions of nitrate RO2 radicals and epoxidation reactions of nitrate alkoxy radicals. Measurements using mass spectrometer instruments give evidence that the new reactions pathways predicted by quantum chemical calculations play a role in the NO3 oxidation of isoprene. Hydroperoxy aldehydes (HPALD), which are specific for unimolecular reactions of nitrate RO2 , were detected even in the presence of an OH scavenger excluding the possibility that concurrent oxidation by hydroxyl radicals (OH) is responsible for their formation. In addition, epoxy compounds, which are specific for the epoxidation reaction of nitrate alkoxy radicals, were detected. Measurements of methyl vinyl ketone (MVK) and methacrolein (MACR) concentrations confirm that the decomposition of nitrate alkoxy radicals implemented in the CalTech mechanism cannot compete with the ring-closure reactions predicted by quantum-chemical calculations. The validity of the FZJ-NO3 isoprene mechanism is further supported by an accurate simulation of the measured hydroxyl radical (OH) reactivity. Nevertheless, the FZJ-NO3 isoprene mechanism needs further investigations with respect to the absolute importance of unimolecular reactions of nitrate RO2 and epoxidation reactions of nitrate alkoxy radicals. Absolute concentrations of specific organic nitrates such as nitrate hydroperoxides would be required to experimentally determine product yields and branching ratios of reactions but could not be measured in the chamber experiments due to the lack of calibration standards for these compounds. The temporal evolution of mass traces attributed to products species such as nitrate hydroperoxides, nitrate carbonyl, nitrate alcohols as well as hydroperoxy aldehydes observed by the mass spectrometer instruments demonstrates that further oxidation by the nitrate radical and ozone at atmospheric concentrations is not relevant on the typical time scale of one night (12 hours). However, oxidation by hydroxyl radicals present at night and potentially also produced from the decomposition of nitrate alkoxy radicals can contribute to their nocturnal chemical loss. [ABSTRACT FROM AUTHOR]- Published
- 2022
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- View/download PDF
26. Chemical characterisation of benzene oxidation products under high- and low-NO<sub><i>x</i></sub> conditions using chemical ionisation mass spectrometry
- Author
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Priestley, Michael, primary, Bannan, Thomas J., additional, Le Breton, Michael, additional, Worrall, Stephen D., additional, Kang, Sungah, additional, Pullinen, Iida, additional, Schmitt, Sebastian, additional, Tillmann, Ralf, additional, Kleist, Einhard, additional, Zhao, Defeng, additional, Wildt, Jürgen, additional, Garmash, Olga, additional, Mehra, Archit, additional, Bacak, Asan, additional, Shallcross, Dudley E., additional, Kiendler-Scharr, Astrid, additional, Hallquist, Åsa M., additional, Ehn, Mikael, additional, Coe, Hugh, additional, Percival, Carl J., additional, Hallquist, Mattias, additional, Mentel, Thomas F., additional, and McFiggans, Gordon, additional
- Published
- 2021
- Full Text
- View/download PDF
27. Chemical characterisation of benzene oxidation products under high and low NOx conditions using chemical ionisation mass spectrometry
- Author
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Priestley, Michael, Bannan, Thomas J., Breton, Michael, Worrall, Stephen D., Kang, Sungah, Pullinen, Iida, Schmitt, Sebastian, Tillmann, Ralf, Kleist, Einhard, Zhao, Defeng, Wildt, Jürgen, Garmash, Olga, Mehra, Archit, Bacak, Asan, Shallcross, Dudley E., Halquist, Åsa, Ehn, Mikael, Kiendler-Scharr, Astrid, Mentel, Thomas F., McFiggans, Gordon, Halquist, Mattias, Coe, Hugh, and Percival, Carl J.
- Abstract
Aromatic hydrocarbons are a class of volatile organic compounds associated with anthropogenic activity and make up a significant fraction of urban VOC emissions that contribute to the formation of secondary organic aerosol (SOA). Benzene is one of the most abundant species emitted from vehicles, biomass burning and industry. An iodide time of flight chemical ionisation mass spectrometer (ToF-CIMS) and nitrate ToF-CIMS were deployed at the Jülich plant chamber as part of a series of experiments examining benzene oxidation by OH under high and low NOx conditions, where a range of organic oxidation products were detected. The nitrate scheme detects many oxidation products with high masses ranging from intermediate volatile organic compounds (IVOC) to extremely low volatile organic compounds (ELVOC), including C12 dimers. In comparison, very few species with C≥6 and O≥8 were detected with the iodide scheme, which detected many more IVOC and semi volatile organic compounds (SVOC) but very few ELVOC and low volatile organic compounds (LVOC). 132 and 195 CHO and CHON oxidation products are detected by the iodide ToF-CIMS in the low and high NOx experiments respectively. Ring breaking products make up the dominant fraction of detected signal (89–91 %). 21 and 26 of the products listed in the master chemical mechanism (MCM) were detected and account for 6.4–7.3 % of total signal. The time series of highly oxidised (O≥6) and ring retaining oxidation products (C6 and double bond equivalent = 4) equilibrate quickly characterised by a square form profile, compared to MCM and ring breaking products which increase throughout oxidation exhibiting saw tooth profiles. Under low NOx conditions, all CHO formulae attributed to radical termination reactions of 1st generation benzene products and 1st generation autoxidation products are observed, and one exclusively 2nd generation autoxidation product is also measured (C6H8O8). Several N containing species that are either 1st generation benzene products or 1st generation autoxidation products are also observed under high NOx conditions. Hierarchical cluster analysis finds four cluster of which two describe photo-oxidation. Cluster 2 shows a negative dependency on the NO2/NOx ratio indicating it is sensitive to NO concentration thus likely to contain NO addition products and alkoxy derived termination products. This cluster has the highest average carbon oxidation state (OSc) and the lowest average carbon number and where nitrogen is present in cluster member, the oxygen number is even, as expected for alkoxy derived products. In contrast, cluster 1 shows no dependency on the NO2/NOx ratio and so is likely to contain more NO2 addition and peroxy derived termination products. This cluster contains less fragmented species, as the average carbon number is higher and OSc lower than cluster 2, and more species with an odd number of oxygen atoms. This suggests clustering of time series which have features pertaining to distinct chemical regimes e.g. NO2/NOx perturbations, coupled with a priori knowledge, can provide insight into identification of potential functionality.
- Published
- 2020
28. New insights into the gas-phase oxidation of isoprene by the nitrate radical from experiments in the atmospheric simulation chamber SAPHIR
- Author
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Carlsson, Philip, Dewald, Patrick, Shenolikar, Justin, Friedrich, Nils, Crowley, John, Brown, Steven, Bernard, François, Zhou, Li, Fry, Juliane, Brownwood, Bellamy, Hallquist, Mattias, Tsiligiannis, Epameinondas, Kangmin, Xu, Holzinger, Rupert, Fuchs, Hendrik, Vereecken, Luc, Novelli, Anna, Bohn, Birger, Rohrer, Franz, Mentel, Thomas, Cho, Changmin, Edwards, Peter, Hantschke, Luisa, Kang, Sungah, Reimer, David, Tillmann, Ralf, Wedel, Sergej, Wu, Rongrong, Max Planck Institute for Chemistry (MPIC), Max-Planck-Gesellschaft, Cancer Research and Biostatistics, Cancer Research Center, Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut des Sciences de l'Ingénierie et des Systèmes (INSIS), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association, Institute for Integrative Biology [Zürich] (IBZ), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), and Centre de recherche de l'école primaire
- Subjects
chemistry.chemical_classification ,Ozonolysis ,Radical ,Photochemistry ,Trace gas ,chemistry.chemical_compound ,[CHIM.GENI]Chemical Sciences/Chemical engineering ,Hydroperoxyl ,chemistry ,Nitrate ,13. Climate action ,[CHIM]Chemical Sciences ,Reactivity (chemistry) ,Alkyl ,Isoprene - Abstract
Experiments at a set of atmospherically relevant conditions were performed in the simulation chamber SAPHIR, investigating the oxidation of isoprene by the nitrate radical (NO3). An extremely comprehensive set of instruments detected trace gases, radicals, aerosol properties and hydroxyl (OH) and NO3 radical reactivity. The chemical conditions in the chamber were varied to change the fate of the peroxy radicals (RO2) formed after the reaction between NO3 and isoprene from either mainly recombining with other RO2 or mainly reacting with hydroperoxyl radicals (HO2). These major atmospheric pathways for RO2 radicals lead to the formation of organic nitrate compounds which then have different atmospheric fates. The experimental concentration profiles are compared to box model calculations using both the current Master Chemical Mechanism (MCM) as well as recently available literature data alongside new quantum chemical calculations. The discussion here focusses on the resulting RO2 distribution and deviations in the predictions of early products and total alkyl nitrate yields for the different chemical conditions. Preliminary results for instance show too high night time losses of alkyl nitrates due to ozonolysis in the current MCM.
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- 2020
29. Impact of NOx on secondary organic aerosol (SOA) formation from α-pinene and β-pinene photooxidation: the role of highly oxygenated organic nitrates
- Author
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Pullinen, Iida, Schmitt, Sebastian, Tillmann, Ralf, Wildt, Jürgen, Wu, Cheng, Zhao, Defeng, Wahner, Andreas, Kiendler-Scharr, Astrid, Kang, Sungah, Sarrafzadeh, Mehrnaz, Schlag, Patrick, Andres, Stefanie, Kleist, Einhard, Mentel, Thomas F., Rohrer, Franz, and Springer, Monika
- Subjects
ddc:550 - Abstract
The formation of organic nitrates (ONs) in the gas phase and their impact on mass formation of secondary organic aerosol (SOA) was investigated in a laboratory study for α-pinene and β-pinene photooxidation. Focus was the elucidation of those mechanisms that cause the often observed suppression of SOA mass formation by NOx, and therein the role of highly oxygenated multifunctional molecules (HOMs). We observed that with increasing NOx concentration (a) the portion of HOM organic nitrates (HOM-ONs) increased, (b) the fraction of accretion products (HOM-ACCs) decreased, and (c) HOM-ACCs contained on average smaller carbon numbers.Specifically, we investigated HOM organic nitrates (HOM-ONs), arising from the termination reactions of HOM peroxy radicals with NOx, and HOM permutation products (HOM-PPs), such as ketones, alcohols, or hydroperoxides, formed by other termination reactions. Effective uptake coefficients γeff of HOMs on particles were determined. HOMs with more than six O atoms efficiently condensed on particles (γeff>0.5 on average), and for HOMs containing more than eight O atoms, every collision led to loss. There was no systematic difference in γeff for HOM-ONs and HOM-PPs arising from the same HOM peroxy radicals. This similarity is attributed to the multifunctional character of the HOMs: as functional groups in HOMs arising from the same precursor HOM peroxy radical are identical, vapor pressures should not strongly depend on the character of the final termination group. As a consequence, the suppressing effect of NOx on SOA formation cannot be simply explained by replacement of terminal functional groups by organic nitrate groups.According to their γeff all HOM-ONs with more than six O atoms will contribute to organic bound nitrate (OrgNO3) in the particulate phase. However, the fraction of OrgNO3 stored in condensable HOMs with molecular masses > 230 Da appeared to be substantially higher than the fraction of particulate OrgNO3 observed by aerosol mass spectrometry. This result suggests losses of OrgNO3 for organic nitrates in particles, probably due to hydrolysis of OrgNO3 that releases HNO3 into the gas phase but leaves behind the organic rest in the particulate phase. However, the loss of HNO3 alone could not explain the observed suppressing effect of NOx on particle mass formation from α-pinene and β-pinene.Instead we can attribute most of the reduction in SOA mass yields with increasing NOx to the significant suppression of gas phase HOM-ACCs, which have high molecular mass and are potentially important for SOA mass formation at low-NOx conditions.
- Published
- 2020
30. Supplementary material to "Molecular composition and volatility of multi-generation products formed from isoprene oxidation by nitrate radical"
- Author
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Wu, Rongrong, primary, Vereecken, Luc, additional, Tsiligiannis, Epameinondas, additional, Kang, Sungah, additional, Albrecht, Sascha R., additional, Hantschke, Luisa, additional, Zhao, Defeng, additional, Novelli, Anna, additional, Fuchs, Hendrik, additional, Tillmann, Ralf, additional, Hohaus, Thorsten, additional, Carlsson, Philip T. M., additional, Shenolikar, Justin, additional, Bernard, François, additional, Crowley, John N., additional, Fry, Juliane L., additional, Brownwood, Bellamy, additional, Thornton, Joel A., additional, Brown, Steven S., additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Hallquist, Matthias, additional, and Mentel, Thomas F., additional
- Published
- 2020
- Full Text
- View/download PDF
31. Molecular composition and volatility of multi-generation products formed from isoprene oxidation by nitrate radical
- Author
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Wu, Rongrong, primary, Vereecken, Luc, additional, Tsiligiannis, Epameinondas, additional, Kang, Sungah, additional, Albrecht, Sascha R., additional, Hantschke, Luisa, additional, Zhao, Defeng, additional, Novelli, Anna, additional, Fuchs, Hendrik, additional, Tillmann, Ralf, additional, Hohaus, Thorsten, additional, Carlsson, Philip T. M., additional, Shenolikar, Justin, additional, Bernard, François, additional, Crowley, John N., additional, Fry, Juliane L., additional, Brownwood, Bellamy, additional, Thornton, Joel A., additional, Brown, Steven S., additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Hallquist, Matthias, additional, and Mentel, Thomas F., additional
- Published
- 2020
- Full Text
- View/download PDF
32. Supplementary material to "Highly oxygenated organic molecules (HOM) formation in the isoprene oxidation by NO3 radical"
- Author
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Zhao, Defeng, primary, Pullinen, Iida, additional, Fuchs, Hendrik, additional, Schrade, Stephanie, additional, Wu, Rongrong, additional, Acir, Ismail-Hakki, additional, Tillmann, Ralf, additional, Rohrer, Franz, additional, Wildt, Jürgen, additional, Guo, Yindong, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Kang, Sungah, additional, Vereecken, Luc, additional, and Mentel, Thomas F., additional
- Published
- 2020
- Full Text
- View/download PDF
33. Highly oxygenated organic molecules (HOM) formation in the isoprene oxidation by NO3 radical
- Author
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Zhao, Defeng, primary, Pullinen, Iida, additional, Fuchs, Hendrik, additional, Schrade, Stephanie, additional, Wu, Rongrong, additional, Acir, Ismail-Hakki, additional, Tillmann, Ralf, additional, Rohrer, Franz, additional, Wildt, Jürgen, additional, Guo, Yindong, additional, Kiendler-Scharr, Astrid, additional, Wahner, Andreas, additional, Kang, Sungah, additional, Vereecken, Luc, additional, and Mentel, Thomas F., additional
- Published
- 2020
- Full Text
- View/download PDF
34. Impact of NO<sub><i>x</i></sub> on secondary organic aerosol (SOA) formation from <i>α</i>-pinene and <i>β</i>-pinene photooxidation: the role of highly oxygenated organic nitrates
- Author
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Pullinen, Iida, primary, Schmitt, Sebastian, additional, Kang, Sungah, additional, Sarrafzadeh, Mehrnaz, additional, Schlag, Patrick, additional, Andres, Stefanie, additional, Kleist, Einhard, additional, Mentel, Thomas F., additional, Rohrer, Franz, additional, Springer, Monika, additional, Tillmann, Ralf, additional, Wildt, Jürgen, additional, Wu, Cheng, additional, Zhao, Defeng, additional, Wahner, Andreas, additional, and Kiendler-Scharr, Astrid, additional
- Published
- 2020
- Full Text
- View/download PDF
35. Chemical characterisation of benzene oxidation products under high and low NOx conditions using chemical ionisation mass spectrometry
- Author
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Priestley, Michael, primary, Bannan, Thomas J., additional, Le Breton, Michael, additional, Worrall, Stephen D., additional, Kang, Sungah, additional, Pullinen, Iida, additional, Schmitt, Sebastian, additional, Tillmann, Ralf, additional, Kleist, Einhard, additional, Zhao, Defeng, additional, Wildt, Jürgen, additional, Garmash, Olga, additional, Mehra, Archit, additional, Bacak, Asan, additional, Shallcross, Dudley E., additional, Halquist, Åsa, additional, Ehn, Mikael, additional, Kiendler-Scharr, Astrid, additional, Mentel, Thomas F., additional, McFiggans, Gordon, additional, Halquist, Mattias, additional, Coe, Hugh, additional, and Percival, Carl J., additional
- Published
- 2020
- Full Text
- View/download PDF
36. Supplementary material to "Chemical characterisation of benzene oxidation products under high and low NOx conditions using chemical ionisation mass spectrometry"
- Author
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Priestley, Michael, primary, Bannan, Thomas J., additional, Le Breton, Michael, additional, Worrall, Stephen D., additional, Kang, Sungah, additional, Pullinen, Iida, additional, Schmitt, Sebastian, additional, Tillmann, Ralf, additional, Kleist, Einhard, additional, Zhao, Defeng, additional, Wildt, Jürgen, additional, Garmash, Olga, additional, Mehra, Archit, additional, Bacak, Asan, additional, Shallcross, Dudley E., additional, Halquist, Åsa, additional, Ehn, Mikael, additional, Kiendler-Scharr, Astrid, additional, Mentel, Thomas F., additional, McFiggans, Gordon, additional, Halquist, Mattias, additional, Coe, Hugh, additional, and Percival, Carl J., additional
- Published
- 2020
- Full Text
- View/download PDF
37. Nighttime to daytime transition of the oxidation products of isoprene by NO3 radicals
- Author
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Tsiligiannis, Epameinondas, primary, Wu, Rongrong, additional, Kang, Sungah, additional, Hantschke, Luisa, additional, Thornton, Joel, additional, Fuchs, Hendrik, additional, Mentel, Thomas, additional, and Hallquist, Mattias, additional
- Published
- 2020
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38. The effect of NOx on formation of Highly Oxidized Multifunctional Molecules and SOA formation in photochemical system of α-pinene and β-pinene
- Author
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Kang, Sungah, primary, Mentel, Thomas, additional, Pullinen, Iida, additional, Springer, Monika, additional, Kleist, Einhard, additional, Schmitt, Sebastian, additional, Wu, Cheng, additional, Proff, Silvia, additional, Vereecken, Luc, additional, Wildt, Jürgen, additional, and Kiendler-Scharr, Astrid, additional
- Published
- 2020
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39. Supplementary material to "Impact of NOx on secondary organic aerosol (SOA) formation from α-pinene and β-pinene photo-oxidation: the role of highly oxygenated organic nitrates"
- Author
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Pullinen, Iida, primary, Schmitt, Sebastian, additional, Kang, Sungah, additional, Sarrafzadeh, Mehrnaz, additional, Schlag, Patrick, additional, Andres, Stefanie, additional, Kleist, Einhard, additional, Mentel, Thomas F., additional, Rohrer, Franz, additional, Springer, Monika, additional, Tillmann, Ralf, additional, Wildt, Jürgen, additional, Wu, Cheng, additional, Zhao, Defeng, additional, Wahner, Andreas, additional, and Kiendler-Scharr, Astrid, additional
- Published
- 2020
- Full Text
- View/download PDF
40. Impact of NOx on secondary organic aerosol (SOA) formation from α-pinene and β-pinene photo-oxidation: the role of highly oxygenated organic nitrates
- Author
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Pullinen, Iida, primary, Schmitt, Sebastian, additional, Kang, Sungah, additional, Sarrafzadeh, Mehrnaz, additional, Schlag, Patrick, additional, Andres, Stefanie, additional, Kleist, Einhard, additional, Mentel, Thomas F., additional, Rohrer, Franz, additional, Springer, Monika, additional, Tillmann, Ralf, additional, Wildt, Jürgen, additional, Wu, Cheng, additional, Zhao, Defeng, additional, Wahner, Andreas, additional, and Kiendler-Scharr, Astrid, additional
- Published
- 2020
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41. Measurements of hydroperoxy radicals (HO<sub>2</sub>) at atmospheric concentrations using bromide chemical ionisation mass spectrometry
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Albrecht, Sascha R., primary, Novelli, Anna, additional, Hofzumahaus, Andreas, additional, Kang, Sungah, additional, Baker, Yare, additional, Mentel, Thomas, additional, Wahner, Andreas, additional, and Fuchs, Hendrik, additional
- Published
- 2019
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42. Highly Oxygenated Organic Nitrates Formed from NO3Radical-Initiated Oxidation of β-Pinene
- Author
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Shen, Hongru, Zhao, Defeng, Pullinen, Iida, Kang, Sungah, Vereecken, Luc, Fuchs, Hendrik, Acir, Ismail-Hakki, Tillmann, Ralf, Rohrer, Franz, Wildt, Jürgen, Kiendler-Scharr, Astrid, Wahner, Andreas, and Mentel, Thomas F.
- Abstract
The reactions of biogenic volatile organic compounds (BVOC) with the nitrate radicals (NO3) are major night-time sources of organic nitrates and secondary organic aerosols (SOA) in regions influenced by BVOC and anthropogenic emissions. In this study, the formation of gas-phase highly oxygenated organic molecules-organic nitrates (HOM-ON) from NO3-initiated oxidation of a representative monoterpene, β-pinene, was investigated in the SAPHIR chamber (Simulation of Atmosphere PHotochemistry In a large Reaction chamber). Six monomer (C = 7–10, N = 1–2, O = 6–16) and five accretion product (C = 17–20, N = 2–4, O = 9–22) families were identified and further classified into first- or second-generation products based on their temporal behavior. The time lag observed in the peak concentrations between peroxy radicals containing odd and even number of oxygen atoms, as well as between radicals and their corresponding termination products, provided constraints on the HOM-ON formation mechanism. The HOM-ON formation can be explained by unimolecular or bimolecular reactions of peroxy radicals. A dominant portion of carbonylnitrates in HOM-ON was detected, highlighting the significance of unimolecular termination reactions by intramolecular H-shift for the formation of HOM-ON. A mean molar yield of HOM-ON was estimated to be 4.8% (−2.6%/+5.6%), suggesting significant HOM-ON contributions to the SOA formation.
- Published
- 2021
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- View/download PDF
43. Molecular composition and volatility of multi-generation products formed from isoprene oxidation by nitrate radical.
- Author
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Wu, Rongrong, Vereecken, Luc, Tsiligiannis, Epameinondas, Kang, Sungah, Albrecht, Sascha R., Hantschke, Luisa, Zhao, Defeng, Novelli, Anna, Fuchs, Hendrik, Tillmann, Ralf, Hohaus, Thorsten, Carlsson, Philip T. M., Shenolikar, Justin, Bernard, François, Crowley, John N., Fry, Juliane L., Brownwood, Bellamy, Thornton, Joel A., Brown, Steven S., and Kiendler-Scharr, Astrid
- Abstract
Isoprene oxidation by nitrate radical (NO
3 ) is a potentially important source of secondary organic aerosol (SOA). It is suggested that the second or later-generation products are the more substantial contributors to SOA. However, there are few studies investigating the multi-generation chemistry of isoprene-NO3 reaction, and information about the volatility of different isoprene nitrates, which is essential to evaluate their potential to form SOA and determine their atmospheric fate, is rare. In this work, we studied the reaction between isoprene and NO3 in the SAPHIR chamber (Jülich) under near atmospheric conditions. Various oxidation products were measured by a high-resolution time-of-flight chemical ionization mass spectrometer using Br− as the reagent ion. They are grouped into monomers (C4 - and C5 -products), and dimers (C10 -products) with 1–3 nitrate groups according to their chemical composition. Most of the observed products match expected termination products observed in previous studies, but some compounds such as monomers and dimers with three nitrogen atoms were rarely reported in the literature as gas-phase products from isoprene oxidation by NO3 . Possible formation mechanisms for these compounds are proposed. The multi-generation chemistry of isoprene and NO3 is characterized by taking advantages of the time behavior of different products. In addition, the vapor pressures of diverse isoprene nitrates are calculated by different parametrization methods. An estimation of the vapor pressure is also derived from their condensation behavior. According to our results, isoprene monomers belong to intermediate volatility or semi-volatile organic compounds and thus have little effect on SOA formation. In contrast, the dimers are expected to have low or extremely low volatility, indicating that they are potentially substantial contributors to SOA. However, the monomers constitute 80 % of the total explained signals on average, while the dimers contribute less than 2 %, suggesting that the contribution of isoprene NO3 oxidation to SOA by condensation should be low under atmospheric conditions. We expect a SOA mass yield of about 5 % from the wall loss and dilution corrected mass concentrations, assuming that all of the isoprene dimers in the low- or extremely low-volatility organic compound (LVOC or ELVOC) range will condense completely. [ABSTRACT FROM AUTHOR]- Published
- 2020
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44. Chemical characterisation of benzene oxidation products under high and low NOx conditions using chemical ionisation mass spectrometry.
- Author
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Priestley, Michael, Bannan, Thomas J., Breton, Michael Le, Worrall, Stephen D., Kang, Sungah, Pullinen, Iida, Schmitt, Sebastian, Tillmann, Ralf, Kleist, Einhard, Zhao, Defeng, Wildt, Jürgen, Garmash, Olga, Mehra, Archit, Bacak, Asan, Shallcross, Dudley E., Halquist, Åsa, Ehn, Mikael, Kiendler-Scharr, Astrid, Mentel, Thomas F., and McFiggans, Gordon
- Abstract
Aromatic hydrocarbons are a class of volatile organic compounds associated with anthropogenic activity and make up a significant fraction of urban VOC emissions that contribute to the formation of secondary organic aerosol (SOA). Benzene is one of the most abundant species emitted from vehicles, biomass burning and industry. An iodide time of flight chemical ionisation mass spectrometer (ToF-CIMS) and nitrate ToF-CIMS were deployed at the Jülich plant chamber as part of a series of experiments examining benzene oxidation by OH under high and low NO
x conditions, where a range of organic oxidation products were detected. The nitrate scheme detects many oxidation products with high masses ranging from intermediate volatile organic compounds (IVOC) to extremely low volatile organic compounds (ELVOC), including C12 dimers. In comparison, very few species with C≥6 and O≥8 were detected with the iodide scheme, which detected many more IVOC and semi volatile organic compounds (SVOC) but very few ELVOC and low volatile organic compounds (LVOC). 132 and 195 CHO and CHON oxidation products are detected by the iodide ToF-CIMS in the low and high NOx experiments respectively. Ring breaking products make up the dominant fraction of detected signal (89-91 %). 21 and 26 of the products listed in the master chemical mechanism (MCM) were detected and account for 6.4-7.3 % of total signal. The time series of highly oxidised (O≥6 ) and ring retaining oxidation products (C6 and double bond equivalent = 4) equilibrate quickly characterised by a square form profile, compared to MCM and ring breaking products which increase throughout oxidation exhibiting saw tooth profiles. Under low NOx conditions, all CHO formulae attributed to radical termination reactions of 1st generation benzene products and 1st generation autoxidation products are observed, and one exclusively 2nd generation autoxidation product is also measured (C6 H8 O8 ). Several N containing species that are either 1st generation benzene products or 1st generation autoxidation products are also observed under high NOx conditions. Hierarchical cluster analysis finds four cluster of which two describe photo-oxidation. Cluster 2 shows a negative dependency on the NO2 /NOx ratio indicating it is sensitive to NO concentration thus likely to contain NO addition products and alkoxy derived termination products. This cluster has the highest average carbon oxidation state (OSc ) and the lowest average carbon number and where nitrogen is present in cluster member, the oxygen number is even, as expected for alkoxy derived products. In contrast, cluster 1 shows no dependency on the NO2 /NOx ratio and so is likely to contain more NO2 addition and peroxy derived termination products. This cluster contains less fragmented species, as the average carbon number is higher and OSc lower than cluster 2, and more species with an odd number of oxygen atoms. This suggests clustering of time series which have features pertaining to distinct chemical regimes e.g. NO2 /NOx perturbations, coupled with a priori knowledge, can provide insight into identification of potential functionality. [ABSTRACT FROM AUTHOR]- Published
- 2020
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45. Measurements of hydroperoxy radicals (HO2) at atmospheric concentrations using bromide chemical ionization mass spectrometry
- Author
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Albrecht, Sascha R., primary, Novelli, Anna, additional, Hofzumahaus, Andreas, additional, Kang, Sungah, additional, Baker, Yare, additional, Mentel, Thomas, additional, Wahner, Andreas, additional, and Fuchs, Hendrik, additional
- Published
- 2018
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46. Hollow and Microporous Zn–Porphyrin Networks: Outer Shape Dependent Ammonia Sensing by Quartz Crystal Microbalance
- Author
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Park, Joon Hyun, primary, Ko, Ju Hong, additional, Hong, Seokjo, additional, Shin, Young Jun, additional, Park, Nojin, additional, Kang, Sungah, additional, Lee, Sang Moon, additional, Kim, Hae Jin, additional, and Son, Seung Uk, additional
- Published
- 2015
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47. Hollow Microporous Organic Networks Bearing Triphenylamines and Anthraquinones: Diffusion Pathway Effect in Visible Light-Driven Oxidative Coupling of Benzylamines
- Author
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Ko, Ju Hong, primary, Kang, Narae, additional, Park, Nojin, additional, Shin, Hee-Won, additional, Kang, Sungah, additional, Lee, Sang Moon, additional, Kim, Hae Jin, additional, Ahn, Tae Kyu, additional, and Son, Seung Uk, additional
- Published
- 2015
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48. Engineering of Sn–porphyrin networks on the silica surface: sensing of nitrophenols in water
- Author
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Ko, Ju Hong, primary, Moon, Jong Hun, additional, Kang, Narae, additional, Park, Joon Hyun, additional, Shin, Hee-Won, additional, Park, Nojin, additional, Kang, Sungah, additional, Lee, Sang Moon, additional, Kim, Hae Jin, additional, Ahn, Tae Kyu, additional, Lee, Jin Yong, additional, and Son, Seung Uk, additional
- Published
- 2015
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49. Hollow and sulfonated microporous organic polymers: versatile platforms for non-covalent fixation of molecular photocatalysts
- Author
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Park, Nojin, primary, Kang, Daye, additional, Ahn, Min Cheol, additional, Kang, Sungah, additional, Lee, Sang Moon, additional, Ahn, Tae Kyu, additional, Jaung, Jae Yun, additional, Shin, Hee-Won, additional, and Son, Seung Uk, additional
- Published
- 2015
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50. Template synthesis of hollow MoS2–carbon nanocomposites using microporous organic polymers and their lithium storage properties
- Author
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Jin, Jaewon, primary, Kim, Bolyong, additional, Kim, Mincheol, additional, Park, Nojin, additional, Kang, Sungah, additional, Lee, Sang Moon, additional, Kim, Hae Jin, additional, and Son, Seung Uk, additional
- Published
- 2015
- Full Text
- View/download PDF
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