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González AG, Bianco A, Boutorh J, Cheize M, Mailhot G, Delort AM, Planquette H, Chaumerliac N, Deguillaume L, Sarthou G. Influence of strong iron-binding ligands on cloud water oxidant capacity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 829:154642. [PMID: 35306063 DOI: 10.1016/j.scitotenv.2022.154642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 03/09/2022] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Iron (Fe) plays a dual role in atmospheric chemistry: it is involved in chemical and photochemical reactivity and serves as a micronutrient for microorganisms that have recently been shown to produce strong organic ligands. These ligands control the reactivity, mobility, solubility and speciation of Fe, which have a potential impact on Fe bioavailability and cloud water oxidant capacity. In this work, the concentrations of Fe-binding ligands and the conditional stability constants were experimentally measured for the first time by Competitive Ligand Exchange-Adsorptive Cathodic Stripping Voltammetry (CLE-ACSV) technique in cloud water samples collected at puy de Dôme (France). The conditional stability constants, which indicate the strength of the Fe-ligand complexes, are higher than those considered until now in cloud chemistry (mainly Fe-oxalate). To understand the effect of Fe complexation on cloud water reactivity, we used the CLEPS cloud chemistry model. According to the model results, we found that Fe complexation impacts the hydroxyl radical formation rate: contrary to our expectations, Fe complexation by natural organic ligands led to an increase in hydroxyl radical production. These findings have important impacts on cloud chemistry and the global iron cycle.
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Affiliation(s)
- Aridane G González
- Instituto de Oceanografía y Cambio Global, IOCAG, Universidad de Las Palmas de Gran Canaria, ULPGC, Spain; CNRS, Univ Brest, IRD, Ifremer, LEMAR, F-29280 Plouzane, France.
| | - Angelica Bianco
- Laboratoire de Météorologie Physique, UMR 6016, CNRS, Université Clermont Auvergne, 63178 Aubière, France.
| | - Julia Boutorh
- CNRS, Univ Brest, IRD, Ifremer, LEMAR, F-29280 Plouzane, France
| | - Marie Cheize
- CNRS, Univ Brest, IRD, Ifremer, LEMAR, F-29280 Plouzane, France
| | - Gilles Mailhot
- CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, Université Clermont Auvergne, F-63000 Clermont-Ferrand, France
| | - Anne-Marie Delort
- CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, Université Clermont Auvergne, F-63000 Clermont-Ferrand, France
| | | | - Nadine Chaumerliac
- Laboratoire de Météorologie Physique, UMR 6016, CNRS, Université Clermont Auvergne, 63178 Aubière, France
| | - Laurent Deguillaume
- Laboratoire de Météorologie Physique, UMR 6016, CNRS, Université Clermont Auvergne, 63178 Aubière, France; Observatoire de Physique du Globe de Clermont-Ferrand, UAR 833, CNRS, Université Clermont Auvergne, 63178 Aubière, France
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Giorio C, D'Aronco S, Di Marco V, Badocco D, Battaglia F, Soldà L, Pastore P, Tapparo A. Emerging investigator series: aqueous-phase processing of atmospheric aerosol influences dissolution kinetics of metal ions in an urban background site in the Po Valley. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:884-897. [PMID: 35611976 DOI: 10.1039/d2em00023g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Metals are an important atmospheric aerosol component; their impacts on health and the environment depend also on their solubility, dissolution kinetics and chemical form in which they are present in the aerosol (e.g., oxidation state, inorganic salt or oxide/hydroxide, organic complex). In this study, we investigated the impact of fog processing on the solubility and dissolution of metals in PM2.5 samples collected in an urban background site in Padova (Italy). For each sample, we determined the solubility and dissolution kinetics of 17 elements in a solution simulating fog water in the winter season in the Po Valley (pH 4.7, T 5 °C, and water content ∼0.5 g m-3). We also determined water-soluble inorganic and organic compounds having ligand properties. We used the model E-AIM IV to calculate the aerosol liquid water (ALW) content and pH, and we used the model Visual MinteQ to determine the speciation picture of the most important elements under conditions of both deliquescent aerosol (ALW and pH calculated using E-AIM IV, ambient temperature) and simulated fog. We found that the dissolution of Al, Cu, and Fe metal ions, predicted to be largely coordinated with organic compounds under fog conditions, was either immediate or considerably faster in samples collected on days with observed fog events compared with those collected on days having drier conditions. For readily soluble elements, such as As, Cd, Cr, Sr, and Zn, such an effect was not observed. Our study highlights the importance of coordination chemistry in atmospheric aerosol and fog in determining the bioavailability of particle-bound metals.
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Affiliation(s)
- Chiara Giorio
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB21EW, UK.
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Sara D'Aronco
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB21EW, UK.
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Valerio Di Marco
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Denis Badocco
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Francesco Battaglia
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB21EW, UK.
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Lidia Soldà
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Paolo Pastore
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Andrea Tapparo
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
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Tilgner A, Schaefer T, Alexander B, Barth M, Collett JL, Fahey KM, Nenes A, Pye HOT, Herrmann H, McNeill VF. Acidity and the multiphase chemistry of atmospheric aqueous particles and clouds. ATMOSPHERIC CHEMISTRY AND PHYSICS 2021; 21:10.5194/acp-21-13483-2021. [PMID: 34675968 PMCID: PMC8525431 DOI: 10.5194/acp-21-13483-2021] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The acidity of aqueous atmospheric solutions is a key parameter driving both the partitioning of semi-volatile acidic and basic trace gases and their aqueous-phase chemistry. In addition, the acidity of atmospheric aqueous phases, e.g., deliquesced aerosol particles, cloud, and fog droplets, is also dictated by aqueous-phase chemistry. These feedbacks between acidity and chemistry have crucial implications for the tropospheric lifetime of air pollutants, atmospheric composition, deposition to terrestrial and oceanic ecosystems, visibility, climate, and human health. Atmospheric research has made substantial progress in understanding feedbacks between acidity and multiphase chemistry during recent decades. This paper reviews the current state of knowledge on these feedbacks with a focus on aerosol and cloud systems, which involve both inorganic and organic aqueous-phase chemistry. Here, we describe the impacts of acidity on the phase partitioning of acidic and basic gases and buffering phenomena. Next, we review feedbacks of different acidity regimes on key chemical reaction mechanisms and kinetics, as well as uncertainties and chemical subsystems with incomplete information. Finally, we discuss atmospheric implications and highlight the need for future investigations, particularly with respect to reducing emissions of key acid precursors in a changing world, and the need for advancements in field and laboratory measurements and model tools.
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Affiliation(s)
- Andreas Tilgner
- Atmospheric Chemistry Department (ACD), Leibniz Institute for Tropospheric Research (TROPOS), Leipzig 04318, Germany
| | - Thomas Schaefer
- Atmospheric Chemistry Department (ACD), Leibniz Institute for Tropospheric Research (TROPOS), Leipzig 04318, Germany
| | - Becky Alexander
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195, USA
| | - Mary Barth
- Atmospheric Chemistry Observation & Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO 80307, USA
| | - Jeffrey L. Collett
- Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523, USA
| | - Kathleen M. Fahey
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC 27711, USA
| | - Athanasios Nenes
- School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland
- Institute for Chemical Engineering Sciences, Foundation for Research and Technology Hellas, Patras 26504, Greece
| | - Havala O. T. Pye
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC 27711, USA
| | - Hartmut Herrmann
- Atmospheric Chemistry Department (ACD), Leibniz Institute for Tropospheric Research (TROPOS), Leipzig 04318, Germany
| | - V. Faye McNeill
- Department of Chemical Engineering, Columbia University, New York, NY 10027, USA
- Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, USA
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4
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Gong H, Cheng C, Li M, Yang S, Zhou Q, Zhong QE, Zhang Y, Xie Y, Zhou Z. The enhanced mixing states of oxalate with metals in single particles in Guangzhou, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 783:146962. [PMID: 33866183 DOI: 10.1016/j.scitotenv.2021.146962] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 04/01/2021] [Accepted: 04/01/2021] [Indexed: 06/12/2023]
Abstract
Recently, internal mixing states of oxalate with metals in single particles have been reported from field studies, yet the role of metals in the formation processes of oxalate remains unclear due to the diversity of chemical components and complex atmospheric environment. In this study, the mixing states of oxalate with five metals, including zinc (Zn), copper (Cu), lead (Pb), vanadium (V) and iron (Fe) were investigated in Guangzhou, China. It was found that 55% of oxalate-containing particles were internally mixed with these metals. The number fraction of oxalate in the metal-containing particles ranged from 5.4-26%, which is much higher than that in the total detected particles (4.0%), indicating significant enrichment of oxalate in the metal-containing particles. Enhanced oxalate production was found in the Fe- and V-containing particles based on distinctly higher relative peak area (RPA) ratios of oxalate to its precursors compared to the total particles, possibly due to enhanced aqueous phase reactions in the Fe- and V-containing particles. However, enrichment of oxalate in the Zn-, Pb-, and Cu-containing particles was possibly associated with complexation of gas phase oxalic acid with the metals, as indicated by the small increase in RPA ratios in these particles. On the other hand, the internal mixing of oxalate with metals was found to provide a way of efficient photolysis of oxalate-metal complexes, which led to a decrease in oxalate after sunrise in the metal-containing particles. In this study, the enhanced mixing states of oxalate with metals have revealed the important role of metals in the production and degradation of oxalate, providing insights for the evaluation of metals in the formation processes of organic aerosol in field studies, which is beneficial to the further study of air pollution in metal emission areas.
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Affiliation(s)
- Haifeng Gong
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China
| | - Chunlei Cheng
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China.
| | - Mei Li
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China.
| | - Suxia Yang
- Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China; Institute for Environment and Climate Research, Jinan University, Guangzhou 510632, China
| | - Qianni Zhou
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China
| | - Qi En Zhong
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China
| | - Yao Zhang
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China
| | - Yutong Xie
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China
| | - Zhen Zhou
- Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollution Jinan University, Guangzhou 510632, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China
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5
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Sciscenko I, Arques A, Varga Z, Bouchonnet S, Monfort O, Brigante M, Mailhot G. Significant role of iron on the fate and photodegradation of enrofloxacin. CHEMOSPHERE 2021; 270:129791. [PMID: 33556815 DOI: 10.1016/j.chemosphere.2021.129791] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/20/2021] [Accepted: 01/24/2021] [Indexed: 05/27/2023]
Abstract
Enrofloxacin (ENR) belongs to the fluoroquinolone (FQ) antibiotics family, which are contaminants of emerging concern frequently found in effluents. Although many works studying photo-Fenton process for FQ degradation have been reported, there are no reports analysing in deep the effect of iron complexation, as well as other metals, towards FQs' photolysis, which, evidently, also contributes in the overall degradation of the pollutant. Therefore, in this work, we report a comparative study between the photochemical fate of ENR and its complex with Fe(III) under simulated sunlight irradiation. In addition, the effect of dissolved oxygen, self-sensitization process, and H2O2 addition on the studied photochemical systems are also investigated. Results indicate that, for free and iron-complexed ENR, singlet oxygen (1O2) is generated from the interaction of its triplet state with ground state oxygen. Half-life time (t1/2) of ENR under sun simulated conditions is estimated to be around 22 min, while complexation with iron enhances its photostability, leading to a t1/2 of 2.1 h. Such finding indicates that at least the presence of iron, might notably increase the residence time of these pollutants in the environment. Eventually, only with the addition of H2O2, the FQ-iron complex is efficiently degraded due to photo-Fenton process even at circumneutral pH values due to the high stability of the formed complex. Finally, after LC/FT-ICR MS analysis, 39 photoproducts are detected, of which the 14 most abundant ones are identified. Results indicate that photoproducts formation is pH and iron dependent.
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Affiliation(s)
- Iván Sciscenko
- Departamento de Ingeniería Textil y Papelera, Universitat Politècnica de València, Alcoy, Spain
| | - Antonio Arques
- Departamento de Ingeniería Textil y Papelera, Universitat Politècnica de València, Alcoy, Spain
| | - Zsuzsanna Varga
- Laboratoire de Chimie Moléculaire - CNRS / Ecole Polytechnique, IP Paris, 91128, Palaiseau, France
| | - Stephane Bouchonnet
- Laboratoire de Chimie Moléculaire - CNRS / Ecole Polytechnique, IP Paris, 91128, Palaiseau, France
| | - Olivier Monfort
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France; Comenius University in Bratislava, Faculty of Natural Sciences, Department of Inorganic Chemistry, Ilkovicova 6, Mlynska Dolina, 84215, Bratislava, Slovakia
| | - Marcello Brigante
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - Gilles Mailhot
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France.
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6
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Butler A, Harder T, Ostrowski AD, Carrano CJ. Photoactive siderophores: Structure, function and biology. J Inorg Biochem 2021; 221:111457. [PMID: 34010741 DOI: 10.1016/j.jinorgbio.2021.111457] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 12/17/2022]
Abstract
It is well known that bacteria and fungi have evolved sophisticated systems for acquiring the abundant but biologically inaccessible trace element iron. These systems are based on high affinity Fe(III)-specific binding compounds called siderophores which function to acquire, transport, and process this essential metal ion. Many hundreds of siderophores are now known and their numbers continue to grow. Extensive studies of their isolation, structure, transport, and molecular genetics have been undertaken in the last three decades and have been comprehensively reviewed many times. In this review we focus on a unique subset of siderophores that has only been recognized in the last 20 years, namely those whose iron complexes display photoactivity. This photoactivity, which typically results in the photooxidation of the siderophore ligand with concomitant reduction of Fe(III) to Fe(II), seemingly upsets the siderophore paradigm of forming and transporting only extremely stable Fe(III) complexes into microbial cells. Here we review their structure, synthesis, photochemistry, photoproduct coordination chemistry and explore the potential biological and ecological consequences of this photoactivity.
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Affiliation(s)
- Alison Butler
- Department of Chemistry and Biochemistry University of California, Santa Barbara, CA 93106 United States
| | - Tilmann Harder
- Department of Biology and Chemistry, University of Bremen, and Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Germany
| | | | - Carl J Carrano
- Department of Chemistry and Biochemistry, San Diego State University, United States.
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7
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Meng J, Li Z, Zhou R, Chen M, Li Y, Yi Y, Ding Z, Li H, Yan L, Hou Z, Wang G. Enhanced photochemical formation of secondary organic aerosols during the COVID-19 lockdown in Northern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 758:143709. [PMID: 33223177 PMCID: PMC7666554 DOI: 10.1016/j.scitotenv.2020.143709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/02/2020] [Accepted: 11/09/2020] [Indexed: 05/09/2023]
Abstract
To eliminate the spread of a novel coronavirus breaking out in the end of 2019 (COVID-19), the Chinese government has implemented a nationwide lockdown policy after the Chinese lunar New Year of 2020, resulting in a sharp reduction in air pollutant emissions. To investigate the impact of the lockdown on aerosol chemistry, the number fraction, size distribution and formation process of oxalic acid (C2) containing particles and its precursors were studied using a single particle aerosol mass spectrometer (SPAMS) at the urban site of Liaocheng in the North China Plain (NCP). Our results showed that five air pollutants (i.e., PM2.5, PM10, SO2, NO2, and CO) decreased by 30.0-59.8% during the lockdown compared to those before the lockdown, while O3 increased by 63.9% during the lockdown mainly due to the inefficient titration effect of O3 via NO reduction. The increased O3 concentration can boost the atmospheric oxidizing capacity and further enhance the formation of secondary organic aerosols, thereby significantly enhancing the C2 particles and its precursors as observed during the lockdown. Before the lockdown, C2 particles were significantly originated from biomass burning emissions and their subsequent aqueous-phase oxidation. The hourly variation patterns and correlation analysis before the lockdown suggested that relative humidity (RH) and aerosol liquid water content (ALWC) played a key role in the formation of C2 particles and the increased aerosol acidity can promote the conversion of precursors such as glyoxal (Gly) and methyglyoxal (mGly) into C2 particles in the aqueous phase. RH and ALWC decreased sharply but O3 concentration and solar radiation increased remarkably during the lockdown, the O3-dominated photochemical pathways played an important role in the formation of C2 particles in which aerosol acidity was ineffective. Our study indicated that air pollution treatment sponges on a joint-control and balanced strategy for controlling numerous pollutants.
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Affiliation(s)
- Jingjing Meng
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Zheng Li
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Ruiwen Zhou
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Min Chen
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Yuanyuan Li
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Yanan Yi
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Zhijian Ding
- Key Laboratory of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200062, China
| | - Hongji Li
- College of Environmental Science and Engineering, Jilin Normal University, Siping 136000, China
| | - Li Yan
- Chinese Academy for Environmental Planning, Beijing 100012, China
| | - Zhanfang Hou
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Gehui Wang
- Key Laboratory of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200062, China.
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8
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Biswakarma J, Kang K, Schenkeveld WDC, Kraemer SM, Hering JG, Hug SJ. Catalytic effects of photogenerated Fe(II) on the ligand-controlled dissolution of Iron(hydr)oxides by EDTA and DFOB. CHEMOSPHERE 2021; 263:128188. [PMID: 33297154 DOI: 10.1016/j.chemosphere.2020.128188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 08/23/2020] [Accepted: 08/26/2020] [Indexed: 06/12/2023]
Abstract
Low bioavailability of iron due to poor solubility of iron(hydr)oxides limits the growth of microorganisms and plants in soils and aquatic environments. Previous studies described accelerated dissolution of iron(hydr)oxides under continuous illumination, but did not distinguish between photoreductive dissolution and non-reductive processes in which photogenerated Fe(II) catalyzes ligand-controlled dissolution. Here we show that short illuminations (5-15 min) accelerate the dissolution of iron(hydr)oxides by ligands during subsequent dark periods under anoxic conditions. Suspensions of lepidocrocite (Lp) and goethite (Gt) (1.13 mM) with 50 μM EDTA or DFOB were illuminated with UV-A light of comparable intensity to sunlight (pH 7.0, bicarbonate-CO2 buffered solutions). During illumination, the rate of Fe(II) production was highest with Gt-EDTA; followed by Lp-EDTA > Lp-DFOB > Lp > Gt-DFOB > Gt. Under anoxic conditions, photochemically produced Fe(II) increased dissolution rates during subsequent dark periods by factors of 10-40 and dissolved Fe(III) reached 50 μM with DFOB and EDTA. Under oxic conditions, dissolution rates increased by factors of 3-5 only during illumination. With DFOB dissolved Fe(III) reached 35 μM after 10 h of illumination, while with EDTA it peaked at 15 μM and then decreased to below 2 μM. The observations are explained and discussed based on a kinetic model. The results suggest that in anoxic bottom water of ponds and lakes, or in microenvironments of algal blooms, short illuminations can dramatically increase the bioavailability of iron by Fe(II)-catalyzed ligand-controlled dissolution. In oxic environments, photostable ligands such as DFOB can maintain Fe(III) in solution during extended illumination.
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Affiliation(s)
- Jagannath Biswakarma
- Swiss Federal Institute of Technology (ETH) Zurich, IBP, CH-8092, Zürich, Switzerland; Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600, Dübendorf, Switzerland
| | - Kyounglim Kang
- University of Vienna, Dept. of Environmental Geosciences, 1090, Vienna, Austria
| | - Walter D C Schenkeveld
- Copernicus Institute of Sustainable Development, Faculty of Geosciences, Utrecht University, 3584, CB Utrecht, the Netherlands
| | - Stephan M Kraemer
- University of Vienna, Dept. of Environmental Geosciences, 1090, Vienna, Austria
| | - Janet G Hering
- Swiss Federal Institute of Technology (ETH) Zurich, IBP, CH-8092, Zürich, Switzerland; Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600, Dübendorf, Switzerland; Swiss Federal Institute of Technology Lausanne (EPFL), ENAC, CH-1015, Lausanne, Switzerland
| | - Stephan J Hug
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600, Dübendorf, Switzerland.
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9
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Yang C, Zhang C, Luo X, Liu X, Cao F, Zhang YL. Isomerization and Degradation of Levoglucosan via the Photo-Fenton Process: Insights from Aqueous-Phase Experiments and Atmospheric Particulate Matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11789-11797. [PMID: 32897062 DOI: 10.1021/acs.est.0c02499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
So far, studies on the conversion of stereochemistry under photo-Fenton conditions and their atmospheric implication are still rare. Here, we found that the biomass burning marker, the chiral compound levoglucosan (L), undergoes oxidative degradation under photo-Fenton conditions and can be isomerized into mannosan (M) and galactosan (G) simultaneously. Among the formic acid, acetic acid, and oxalic acid in the degradation products of levoglucosan, it was found that the yield of formation of formic acid in the photo-Fenton pathway can be as high as 86%. It is worth noting that both levoglucosan and its isomers are present in the atmosphere and their concentrations are strongly correlated. At the same time, the range of their concentration ratios, L/(G + M), measured in the photo-Fenton experiments in the laboratory was found to agree well with that measured in atmospheric PM2.5 samples. However, the sources of L, G, and M in the atmosphere are complex, and the photo-Fenton reaction may be an essential pathway for the distribution of L, G, and M in the atmosphere.
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Affiliation(s)
- Chi Yang
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Chunyan Zhang
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Xiaosan Luo
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Xiaoyan Liu
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Fang Cao
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Yan-Lin Zhang
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
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Wu Y, Qiu T, Wang Y, Liu H, Sun W, Dong W, Mailhot G. Application of a microbial siderophore desferrioxamine B in sunlight/Fe 3+/persulfate system: from the radical formation to the degradation of atenolol at neutral pH. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:36782-36788. [PMID: 32572744 DOI: 10.1007/s11356-020-09692-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
The present work reported a modified persulfate activation process with a microbial siderophore named desferrioxamine B (DFOB). DFOB was a natural complexing agent and could complex with Fe3+ strongly. The photochemical reactivity of Fe(III)-DFOB was studied. Fe2+ and HO• were produced from Fe(III)-DFOB photolysis. Furthermore, the degradation of atenolol (ATL) was followed in light/persulfate (PS)/Fe(III)-DFOB system. The main oxidative radicals were SO4•- in this system. The results of pH effect showed that there was no obviously fluctuation on ATL degradation efficiency with the pH increased from 2.5 to 8.4. Moreover, kSO4•-,DFOB was determined by laser flash photolysis (LFP) experiments. DFOB had positive effect on Fe2+ formation but negative effect on ATL degradation due to the high react rate constant between DFOB and SO4•-. The effects of chloride and carbonate ion were also investigated. The results in this study proposed the reaction mechanism of the modified persulfate activation process, and it could be applied in neutral and weak-alkaline pH range.
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Affiliation(s)
- Yanlin Wu
- Department of Environmental Science & Engineering, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai, 200433, China.
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
- Institut de Chimie de Clermont-Ferrand, SIGMA Clermont, Université Clermont Auvergne, CNRS, F-63000, Clermont-Ferrand, France.
| | - Tian Qiu
- Department of Environmental Science & Engineering, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai, 200433, China
| | - Yu Wang
- Department of Environmental Science & Engineering, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai, 200433, China
| | - Huihui Liu
- Department of Environmental Science & Engineering, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai, 200433, China
| | - Weiqiang Sun
- Department of Environmental Science & Engineering, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai, 200433, China
| | - Wenbo Dong
- Department of Environmental Science & Engineering, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai, 200433, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Gilles Mailhot
- Institut de Chimie de Clermont-Ferrand, SIGMA Clermont, Université Clermont Auvergne, CNRS, F-63000, Clermont-Ferrand, France
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Zhang C, Yang C, Liu X, Cao F, Zhang YL. Insight into the photochemistry of atmospheric oxalate through hourly measurements in the northern suburbs of Nanjing, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 719:137416. [PMID: 32145492 DOI: 10.1016/j.scitotenv.2020.137416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/16/2020] [Accepted: 02/17/2020] [Indexed: 06/10/2023]
Abstract
Oxalate-iron is an integral part of the photochemical system in the atmosphere. Here, we combined high-resolution online observations and laboratory simulations to discuss the distribution of oxalate and oxalate-iron photochemical system in Nanjing atmosphere at the molecular level. The results show that the oxidation state of iron in the oxalate-iron photochemical system changes significantly and regularly. Among them, Fe (II)/Fe (III) is 3.82 during the day and 0.76 at night. At the same time, Cl- may accelerate the generation of hydroxyl radicals in the system and promote the photooxidation rate of oxalate. Oxalate can be converted into formate (C1) and acetate (C2) in the photochemical system, but <4% of degraded oxalate is converted, which means that the photochemical system may not be the main source of formate and acetate in the atmosphere. Besides, the ratio of C1/C2 < 1 in the conversion is opposite to the ratio of C1/C2 > 1 in the general secondary conversion, which means that not all ratio of C1/C2 in the photochemical pathway is >1. These results are beneficial for us to understand the effect of the oxalate-iron photochemical system on the distribution of oxalate in the atmosphere, and also help us to analyze the conversion of organics in the atmospheric aqueous phase.
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Affiliation(s)
- Chunyan Zhang
- Yale-NUIST Center on Atmospheric Environment, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Nanjing University of Information Science and Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China; School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Chi Yang
- Yale-NUIST Center on Atmospheric Environment, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Nanjing University of Information Science and Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China; School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Xiaoyan Liu
- Yale-NUIST Center on Atmospheric Environment, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Nanjing University of Information Science and Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China; School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Fang Cao
- Yale-NUIST Center on Atmospheric Environment, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Nanjing University of Information Science and Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China; School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Yan-Lin Zhang
- Yale-NUIST Center on Atmospheric Environment, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Nanjing University of Information Science and Technology, Nanjing 210044, China; Key Laboratory of Meteorological Disaster Ministry of Education (KLME), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China; School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China.
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Photochemistry of the Cloud Aqueous Phase: A Review. Molecules 2020; 25:molecules25020423. [PMID: 31968643 PMCID: PMC7024559 DOI: 10.3390/molecules25020423] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/12/2020] [Accepted: 01/16/2020] [Indexed: 11/19/2022] Open
Abstract
This review paper describes briefly the cloud aqueous phase composition and deeply its reactivity in the dark and mainly under solar radiation. The role of the main oxidants (hydrogen peroxide, nitrate radical, and hydroxyl radical) is presented with a focus on the hydroxyl radical, which drives the oxidation capacity during the day. Its sources in the aqueous phase, mainly through photochemical mechanisms with H2O2, iron complexes, or nitrate/nitrite ions, are presented in detail. The formation rate of hydroxyl radical and its steady state concentration evaluated by different authors are listed and compared. Finally, a paragraph is also dedicated to the sinks and the reactivity of the HO• radical with the main compounds found in the cloud aqueous phase. This review presents an assessment of the reactivity in the cloud aqueous phase and shows the significant potential impact that this medium can have on the chemistry of the atmosphere and more generally on the climate.
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Bianco A, Deguillaume L, Chaumerliac N, Vaïtilingom M, Wang M, Delort AM, Bridoux MC. Effect of endogenous microbiota on the molecular composition of cloud water: a study by Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Sci Rep 2019; 9:7663. [PMID: 31113999 PMCID: PMC6529453 DOI: 10.1038/s41598-019-44149-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 05/07/2019] [Indexed: 11/23/2022] Open
Abstract
A cloud water sample collected at the puy de Dôme observatory (PUY) has been incubated under dark conditions, with its endogenous microbiota at two different temperatures (5 and 15 °C), and the change in the molecular organic composition of this sample was analyzed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Microorganisms were metabolically active and strongly modified the dissolved organic matter since they were able to form and consume many compounds. Using Venn diagrams, four fractions of compounds were identified: (1) compounds consumed by microbial activity; (2) compounds not transformed during incubation; (3) compounds resulting from dark chemistry (i.e., hydrolysis and Fenton reactions) and, finally, (4) compounds resulting from microbial metabolic activity. At 15 °C, microorganisms were able to consume 58% of the compounds initially present and produce 266 new compounds. For this cloud sample, the impact of dark chemistry was negligible. Decreasing the temperature to 5 °C led to the more efficient degradation of organic compounds (1716 compounds vs. 1094 at 15 °C) but with the less important production of new ones (173). These transformations were analyzed using a division into classes based on the O/C and H/C ratios: lipid-like compounds, aliphatic/peptide-like compounds, carboxylic-rich alicyclic molecule (CRAM)-like structures, carbohydrate-like compounds, unsaturated hydrocarbons, aromatic structures and highly oxygenated compounds (HOCs). Lipid-like, aliphatic/peptide-like and CRAMs-like compounds were the most impacted since they were consumed to maintain the microbial metabolism. On the contrary, the relative percentages of CRAMs and carbohydrates increased after incubation.
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Affiliation(s)
- Angelica Bianco
- Université Clermont Auvergne, CNRS Laboratoire de Météorologie Physique, F-63000, Clermont-Ferrand, France.,CEA, DAM, DIF, F-91297, Arpajon, France
| | - Laurent Deguillaume
- Université Clermont Auvergne, CNRS Laboratoire de Météorologie Physique, F-63000, Clermont-Ferrand, France.
| | - Nadine Chaumerliac
- Université Clermont Auvergne, CNRS Laboratoire de Météorologie Physique, F-63000, Clermont-Ferrand, France
| | - Mickaël Vaïtilingom
- Université Clermont Auvergne, CNRS Laboratoire de Météorologie Physique, F-63000, Clermont-Ferrand, France.,Laboratoire de Recherche en Géosciences et Energies (LaRGE), Departement of Physics, Université des Antilles, Pointe-à-Pitre, France
| | - Miao Wang
- Université Clermont Auvergne, CNRS Laboratoire de Météorologie Physique, F-63000, Clermont-Ferrand, France
| | - Anne-Marie Delort
- Université Clermont Auvergne, CNRS, SIGMA-Clermont, Institut de Chimie de Clermont-Ferrand, F-63000, Clermont-Ferrand, France
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Årstøl E, Hohmann-Marriott MF. Cyanobacterial Siderophores-Physiology, Structure, Biosynthesis, and Applications. Mar Drugs 2019; 17:E281. [PMID: 31083354 PMCID: PMC6562677 DOI: 10.3390/md17050281] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 11/16/2022] Open
Abstract
Siderophores are low-molecular-weight metal chelators that function in microbial iron uptake. As iron limits primary productivity in many environments, siderophores are of great ecological importance. Additionally, their metal binding properties have attracted interest for uses in medicine and bioremediation. Here, we review the current state of knowledge concerning the siderophores produced by cyanobacteria. We give an overview of all cyanobacterial species with known siderophore production, finding siderophores produced in all but the most basal clades, and in a wide variety of environments. We explore what is known about the structure, biosynthesis, and cycling of the cyanobacterial siderophores that have been characterized: Synechobactin, schizokinen and anachelin. We also highlight alternative siderophore functionality and technological potential, finding allelopathic effects on competing phytoplankton and likely roles in limiting heavy-metal toxicity. Methodological improvements in siderophore characterization and detection are briefly described. Since most known cyanobacterial siderophores have not been structurally characterized, the application of mass spectrometry techniques will likely reveal a breadth of variation within these important molecules.
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Affiliation(s)
- Erland Årstøl
- Department of Biotechnology, PhotoSynLab, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Martin F Hohmann-Marriott
- Department of Biotechnology, PhotoSynLab, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
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Amato P, Besaury L, Joly M, Penaud B, Deguillaume L, Delort AM. Metatranscriptomic exploration of microbial functioning in clouds. Sci Rep 2019; 9:4383. [PMID: 30867542 PMCID: PMC6416334 DOI: 10.1038/s41598-019-41032-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 02/27/2019] [Indexed: 01/19/2023] Open
Abstract
Clouds constitute the uppermost layer of the biosphere. They host diverse communities whose functioning remains obscure, although biological activity potentially participates to atmospheric chemical and physical processes. In order to gain information on the metabolic functioning of microbial communities in clouds, we conducted coordinated metagenomics/metatranscriptomics profiling of cloud water microbial communities. Samples were collected from a high altitude atmospheric station in France and examined for biological content after untargeted amplification of nucleic acids. Living microorganisms, essentially bacteria, maintained transcriptional and translational activities and expressed many known complementary physiological responses intended to fight oxidants, osmotic variations and cold. These included activities of oxidant detoxification and regulation, synthesis of osmoprotectants/cryoprotectants, modifications of membranes, iron uptake. Consistently these energy-demanding processes were fueled by central metabolic routes involved in oxidative stress response and redox homeostasis management, such as pentose phosphate and glyoxylate pathways. Elevated binding and transmembrane ion transports demonstrated important interactions between cells and their cloud droplet chemical environments. In addition, polysaccharides, potentially beneficial for survival like exopolysaccharides, biosurfactants and adhesins, were synthesized. Our results support a biological influence on cloud physical and chemical processes, acting notably on the oxidant capacity, iron speciation and availability, amino-acids distribution and carbon and nitrogen fates.
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Affiliation(s)
- Pierre Amato
- Université Clermont Auvergne, CNRS, SIGMA Clermont, ICCF, F-63000, Clermont-Ferrand, France.
| | - Ludovic Besaury
- Université Clermont Auvergne, CNRS, SIGMA Clermont, ICCF, F-63000, Clermont-Ferrand, France
| | - Muriel Joly
- Université Clermont Auvergne, CNRS, SIGMA Clermont, ICCF, F-63000, Clermont-Ferrand, France
| | - Benjamin Penaud
- Université Clermont Auvergne, CNRS, SIGMA Clermont, ICCF, F-63000, Clermont-Ferrand, France
| | | | - Anne-Marie Delort
- Université Clermont Auvergne, CNRS, SIGMA Clermont, ICCF, F-63000, Clermont-Ferrand, France
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17
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Huang DD, Zhang Q, Cheung HHY, Yu L, Zhou S, Anastasio C, Smith JD, Chan CK. Formation and Evolution of aqSOA from Aqueous-Phase Reactions of Phenolic Carbonyls: Comparison between Ammonium Sulfate and Ammonium Nitrate Solutions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:9215-9224. [PMID: 29985589 DOI: 10.1021/acs.est.8b03441] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We investigate the effects of sulfate and nitrate on the formation and evolution of secondary organic aerosol formed in the aqueous phase (aqSOA) from photooxidation of two phenolic carbonyls emitted from wood burning. AqSOA was formed efficiently from the photooxidation of both syringaldehyde (C9H10O4) and acetosyringone (C10H12O4) in ammonium sulfate and ammonium nitrate solutions, with mass yields ranging from 30% to 120%. Positive matrix factorization on the organic mass spectra acquired by an Aerosol Mass Spectrometer revealed a combination of functionalization, oligomerization, and fragmentation processes in the chemical evolution of aqSOA. Functionalization and oligomerization dominated in the first 4 h of reaction, with phenolic oligomers and their derivatives significantly contributing to aqSOA formation; and oxidation of the first-generation products led to an abundance of oxygenated ring-opening products. Degradation rates of syringaldehyde and acetosyringone in nitrate solutions were 1.5 and 3.5 times faster than rates in sulfate solutions, and aqSOA yields in nitrate experiments are twice as high as in sulfate experiments. Nitrate likely promoted the reactions because it is a photolytic source of OH radicals, while sulfate is not, highlighting the importance of aerosol-phase nitrate in the formation of aqSOA by facilitating the photooxidation of organic precursors.
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Affiliation(s)
- Dan Dan Huang
- School of Energy and Environment , City University of Hong Kong , Kowloon , Hong Kong , P. R. China
- Shanghai Academy of Environmental Sciences , Shang Hai 200233 , China
| | - Qi Zhang
- Department of Environmental Toxicology , University of California , Davis , California 95616 , United States
| | - Heidi H Y Cheung
- Division of Environment , Hong Kong of University of Science and Technology , Kowloon , Hong Kong , P. R. China
| | - Lu Yu
- Department of Environmental Toxicology , University of California , Davis , California 95616 , United States
| | - Shan Zhou
- Department of Environmental Toxicology , University of California , Davis , California 95616 , United States
| | - Cort Anastasio
- Department of Land, Air, and Water Resources , University of California , Davis , California 95616 , United States
| | - Jeremy D Smith
- Department of Land, Air, and Water Resources , University of California , Davis , California 95616 , United States
| | - Chak K Chan
- School of Energy and Environment , City University of Hong Kong , Kowloon , Hong Kong , P. R. China
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