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Liu D, Li X, Liu J, Wang F, Leng Y, Li Z, Lu P, Rose NL. Probing the occurrence, sources and cancer risk assessment of polycyclic aromatic hydrocarbons in PM 2.5 in a humid metropolitan city in China. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:902-914. [PMID: 38592781 DOI: 10.1039/d3em00566f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Fifty-two consecutive PM2.5 samples from December 2021 to February 2022 (the whole winter) were collected in the center of Chongqing, a humid metropolitan city in China. These samples were analysed for the 16 USEPA priority polycyclic aromatic hydrocarbons (16 PAHs) to explore their composition and sources, and to assess their cancer risks to humans. The total concentrations of the 16 PAHs (ng m-3) ranged from 16.45 to 174.15, with an average of 59.35 ± 21.45. Positive matrix factorization (PMF) indicated that traffic emissions were the major source (42.4%), followed by coal combustion/industrial emission (31.3%) and petroleum leakage/evaporation (26.3%). The contribution from traffic emission to the 16 PAHs increased from 40.0% in the non-episode days to as high as 46.2% in the air quality episode during the sampling period. The population attributable fraction (PAF) indicates that when the unit relative risk (URR) is 4.49, the number of lung cancer cases per million individuals under PAH exposure is 27 for adults and 38 for seniors, respectively. It was 5 for adults and 7 for seniors, when the URR is 1.3. The average incremental lifetime cancer risk (ILCR) for children, adolescents, adults and seniors was 0.25 × 10-6, 0.23 × 10-6, 0.71 × 10-6, and 1.26 × 10-6, respectively. The results of these two models complemented each other well, and both implied acceptable PAH exposure levels. Individual genetic susceptibility and exposure time were identified as the most sensitive parameters. The selection and use of parameters in risk assessment should be further deepened in subsequent studies to enhance the reliability of the assessment results.
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Affiliation(s)
- Decai Liu
- College of Environment and Ecology, Chongqing University, Chongqing 400030, China.
| | - Xingquan Li
- College of Environment and Ecology, Chongqing University, Chongqing 400030, China.
| | - Jiaxin Liu
- Chongqing University Cancer Hospital, Chongqing University, Chongqing 400030, China
| | - Fengwen Wang
- College of Environment and Ecology, Chongqing University, Chongqing 400030, China.
- Key Laboratory for Urban Atmospheric Environment Integrated Observation & Pollution Prevention and Control of Chongqing, Chongqing Academy of Eco-Environmental Sciences, Chongqing 401147, China
| | - Yan Leng
- Chongqing Dianjiang Middle School, Dianjiang, Chongqing, 408303, China
| | - Zhenliang Li
- Key Laboratory for Urban Atmospheric Environment Integrated Observation & Pollution Prevention and Control of Chongqing, Chongqing Academy of Eco-Environmental Sciences, Chongqing 401147, China
| | - Peili Lu
- College of Environment and Ecology, Chongqing University, Chongqing 400030, China.
| | - Neil L Rose
- Environmental Change Research Centre, University College London, Gower Street, London WC1E 6BT, UK
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Li LF, Chen Z, Liu P, Zhang YH. Direct Measurement of pH Evolution in Aerosol Microdroplets Undergoing Ammonium Depletion: A Surface-Enhanced Raman Spectroscopy Approach. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:6274-6281. [PMID: 35476405 DOI: 10.1021/acs.est.1c08626] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Accurately measuring the pH of atmospheric aerosols is a prerequisite for understanding the multiphase chemistry that profoundly affects the environment and climate systems. Despite the advancements of experimental techniques for in situ pH measurements in aerosols, current studies are limited to measuring the static pH of aerosol microdroplets with an unperturbed composition. This steady-state scenario, however, deviates from the real-world aerosols undergoing atmospheric aging reactions, specifically, those characterized with a spontaneous displacement of strong bases (or acids) with high volatility. Here, we introduce a continuous and in situ measurement of aerosol pH by using a 4-mercaptopyridine-functionalized silver nanoparticle probe and surface-enhanced Raman spectroscopy. We find that the ammonium depletion─a spontaneous displacement of ammonium by dicarboxylic acid salts─continuously acidifies aerosol water over time. The decaying trends of pH in the aerosols under various humidity conditions can be unified with a universal exponential function. Such an exponentially decaying function further indicates that the ammonium depletion reaction is a self-limiting process. Our technique can be applied to study the dynamic change of aerosol acidity during the complex atmospheric aging processes, toward elucidating their implications on atmospheric chloride, nitrate, and ammonium cycles.
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Affiliation(s)
- Lin-Fang Li
- Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Zhe Chen
- Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Pai Liu
- Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yun-Hong Zhang
- Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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3
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Source Apportionment and Toxic Potency of PM2.5-Bound Polycyclic Aromatic Hydrocarbons (PAHs) at an Island in the Middle of Bohai Sea, China. ATMOSPHERE 2022. [DOI: 10.3390/atmos13050699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) have attracted more attention because of their high atmospheric concentration and toxicity in recent decades. In this study, a total of 60 PM2.5 samples were collected from Beihuangcheng Island in Bohai Sea, China, from August 2017 to March 2018 for analyzing 16 congeners of PAHs (Σ16PAHs). Sources of PAHs were apportioned by a positive matrix factorization (PMF) model and the carcinogenic risk due to exposure to the PAHs was estimated by the toxicity equivalent of BaP (BaPeq). The results showed that the average concentration of Σ16PAHs was 35.3 ± 41.8 ng/m3. The maximum concentration of Σ16PAHs occurred in winter, followed by spring and autumn, and summer. The PMF modeling apportioned the PAHs into four sources, coal combustion, biomass burning, vehicle exhaust, and petroleum release, contributing 43.1%, 25.8%, 24.7%, and 6.39%, respectively. The average ΣBaPeq concentration was 2.32 ± 4.95 ng/m3 during the sampling period, and vehicle exhaust was the largest contributor. The finding indicates that more attention should be paid to reduce the emissions from coal combustion and vehicle exhaust because they were the largest contributors to the PAH concentration in PM2.5 and ΣBaPeq concentration, respectively.
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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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5
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Lei Z, Bliesner SE, Mattson CN, Cooke ME, Olson NE, Chibwe K, Albert JNL, Ault AP. Aerosol Acidity Sensing via Polymer Degradation. Anal Chem 2020; 92:6502-6511. [PMID: 32227877 DOI: 10.1021/acs.analchem.9b05766] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The acidity of atmospheric aerosols is a critical property that affects the chemistry and composition of the atmosphere. Many key multiphase chemical reactions are pH-dependent, impacting processes like secondary organic aerosol formation, and need to be understood at a single particle level due to differences in particle-to-particle composition that impact both climate and health. However, the analytical challenge of measuring aerosol acidity in individual particles has limited pH measurements for fine (<2.5 μm) and coarse (2.5-10 μm) particles. This has led to a reliance on indirect methods or thermodynamic modeling, which focus on average, not individual, particle pH. Thus, new approaches are needed to probe single particle pH. In this study, a novel method for pH measurement was explored using degradation of a pH-sensitive polymer, poly(ε-caprolactone), to determine the acidity of individual submicron particles. Submicron particles of known pH (0 or 6) were deposited on a polymer film (21-25 nm thick) and allowed to react. Particles were then rinsed off, and the degradation of the polymer was characterized using atomic force microscopy and Raman microspectroscopy. After degradation, holes in the PCL films exposed to pH 0 were observed, and the loss of the carbonyl stretch was monitored at 1723 cm-1. As particle size decreased, polymer degradation increased, indicating an increase in aerosol acidity at smaller particle diameters. This study describes a new approach to determine individual particle acidity and is a step toward addressing a key measurement gap related to our understanding of atmospheric aerosol impacts on climate and health.
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Affiliation(s)
- Ziying Lei
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Samuel E Bliesner
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Claire N Mattson
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Madeline E Cooke
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Nicole E Olson
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Kaseba Chibwe
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Julie N L Albert
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Andrew P Ault
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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6
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Pye HOT, Nenes A, Alexander B, Ault AP, Barth MC, Clegg SL, Collett JL, Fahey KM, Hennigan CJ, Herrmann H, Kanakidou M, Kelly JT, Ku IT, McNeill VF, Riemer N, Schaefer T, Shi G, Tilgner A, Walker JT, Wang T, Weber R, Xing J, Zaveri RA, Zuend A. The Acidity of Atmospheric Particles and Clouds. ATMOSPHERIC CHEMISTRY AND PHYSICS 2020; 20:4809-4888. [PMID: 33424953 PMCID: PMC7791434 DOI: 10.5194/acp-20-4809-2020] [Citation(s) in RCA: 155] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Acidity, defined as pH, is a central component of aqueous chemistry. In the atmosphere, the acidity of condensed phases (aerosol particles, cloud water, and fog droplets) governs the phase partitioning of semi-volatile gases such as HNO3, NH3, HCl, and organic acids and bases as well as chemical reaction rates. It has implications for the atmospheric lifetime of pollutants, deposition, and human health. Despite its fundamental role in atmospheric processes, only recently has this field seen a growth in the number of studies on particle acidity. Even with this growth, many fine particle pH estimates must be based on thermodynamic model calculations since no operational techniques exist for direct measurements. Current information indicates acidic fine particles are ubiquitous, but observationally-constrained pH estimates are limited in spatial and temporal coverage. Clouds and fogs are also generally acidic, but to a lesser degree than particles, and have a range of pH that is quite sensitive to anthropogenic emissions of sulfur and nitrogen oxides, as well as ambient ammonia. Historical measurements indicate that cloud and fog droplet pH has changed in recent decades in response to controls on anthropogenic emissions, while the limited trend data for aerosol particles indicates acidity may be relatively constant due to the semi-volatile nature of the key acids and bases and buffering in particles. This paper reviews and synthesizes the current state of knowledge on the acidity of atmospheric condensed phases, specifically particles and cloud droplets. It includes recommendations for estimating acidity and pH, standard nomenclature, a synthesis of current pH estimates based on observations, and new model calculations on the local and global scale.
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Affiliation(s)
- Havala O. T. Pye
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, USA
| | - Athanasios Nenes
- School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
- Institute for Chemical Engineering Sciences, Foundation for Research and Technology Hellas, Patras, GR-26504, Greece
| | - Becky Alexander
- Department of Atmospheric Science, University of Washington, Seattle, WA, 98195, USA
| | - Andrew P. Ault
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109-1055, USA
| | - Mary C. Barth
- National Center for Atmospheric Research, Boulder, CO, 80307, USA
| | - Simon L. Clegg
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - 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, NC, 27711, USA
| | - Christopher J. Hennigan
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD, 21250, USA
| | - Hartmut Herrmann
- Leibniz Institute for Tropospheric Research (TROPOS), Atmospheric Chemistry Department (ACD), Leipzig, 04318, Germany
| | - Maria Kanakidou
- Department of Chemistry, University of Crete, Voutes, Heraklion Crete, 71003, Greece
| | - James T. Kelly
- Office of Air Quality Planning & Standards, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, USA
| | - I-Ting Ku
- Department of Atmospheric Science, Colorado State University, Fort Collins, CO, 80523, USA
| | - V. Faye McNeill
- Department of Chemical Engineering, Columbia University, New York, NY, 10027, USA
| | - Nicole Riemer
- Department of Atmospheric Sciences, University of Illinois at Urbana-Champaign, Urbana-Champaign, Illinois, 61801, USA
| | - Thomas Schaefer
- Leibniz Institute for Tropospheric Research (TROPOS), Atmospheric Chemistry Department (ACD), Leipzig, 04318, Germany
| | - Guoliang Shi
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, Nankai University, Tianjin, 300071, China
| | - Andreas Tilgner
- Leibniz Institute for Tropospheric Research (TROPOS), Atmospheric Chemistry Department (ACD), Leipzig, 04318, Germany
| | - John T. Walker
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, USA
| | - Tao Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Rodney Weber
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Jia Xing
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Rahul A. Zaveri
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Andreas Zuend
- Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, H3A 0B9, Canada
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Tang S, Zhou X, Zhang J, Xue L, Luo Y, Song J, Wang W. Characteristics of water-soluble organic acids in PM 2.5 during haze and Chinese Spring Festival in winter of Jinan, China: concentrations, formations, and source apportionments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:12122-12137. [PMID: 31989492 DOI: 10.1007/s11356-020-07714-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 01/10/2020] [Indexed: 06/10/2023]
Abstract
PM2.5 aerosols from Jinan (36°256'N, 117°106'E) in the North China Plain region were investigated for water-soluble organic acids (WSOAs, i.e., oxalic acid, formic acid, acetic acid, methanesulfonic acid (MSA), and lactic acid) during 30 December 2016 to 21 February 2017. The average PM2.5 concentration was 168.77 μg/m3 with about 90.74% samples beyond the National Ambient Air Quality (NAAQ) standards (Grade II). The total concentration of the measured WSOAs averaged at 1.34 μg/m3, contributing to 0.80% of PM2.5 mass. In the observation, acetic acid was the most abundant WSOA, followed by oxalic acid, lactic acid, formic acid, and MSA. During the period, serious haze events frequently happened. The average concentrations of PM2.5 and every WSOA species were higher in haze than those in non-haze. The correlations among species suggested that WSOAs in haze had complicated sources and secondary pathways, especially aqueous-phase reactions which played an important role on WSOAs. The concentrations of WSOAs declined in the Spring Festival compared with those in the non-Spring Festival due to holiday effect. Fireworks burning during the Spring Festival had different influences on WSOAs with slight increases for acetic acid and lactic acid. Five source factors were identified by positive matrix factorization (PMF) model for five WSOAs, respectively, and the results revealed that secondary reactions were the main sources of WSOAs in haze.
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Affiliation(s)
- Shuting Tang
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China
| | - Xuehua Zhou
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China.
| | - Jingzhu Zhang
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China
| | - Likun Xue
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China
| | - Yuanyuan Luo
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China
| | - Jie Song
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China
| | - Wenxing Wang
- Environment Research Institute, Shandong University (Qingdao), Qingdao, 266237, Shandong, China
- Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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Chang P, Chen Z, Zhang Y, Liu Y. Direct measurement of aerosol pH in individual malonic acid and citric acid droplets under different relative humidity conditions via Raman spectroscopy. CHEMOSPHERE 2020; 241:124960. [PMID: 31590017 DOI: 10.1016/j.chemosphere.2019.124960] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/14/2019] [Accepted: 09/23/2019] [Indexed: 06/10/2023]
Abstract
Acidity of aerosol particles plays important roles in atmospheric chemistry, in turn, impacting climate system and public health. Current knowledge of acidity in atmosphere aerosols remains fairly scarce largely because of difficulty in direct measurement. On the other hand, indirect methods for estimating aerosol pH are often inconsistent with pH values predicted by thermodynamic models. Recently, a direct Raman spectroscopy method has been reported to determine pH values of acid-conjugate base equilibria systems based on Raman intensity of distinct characteristic peaks of conjugate acid-base pair. Nevertheless, for pure carboxylic acid aerosol particles, such as malonic acid (MA), characteristic peak of its conjugate base cannot be clearly observed in Raman spectra owing to small Ka value (weak acid dissociation constant), which leads to little dissociation of weak acid and low concentration of its conjugated base. As a result, pH of carboxylic acid particles cannot be directly determined by calibrating concentrations of acid and its conjugated base using the above-mentioned method. To address such an issue, we demonstrate a new approach for determining pH values of malonic acid (MA) and citric acid (CA) droplets under different relative humidity (RH) based on calibration curves. We measure Raman intensity ratios of acid solutions at different concentrations and their pH values to establish a calibration curve, and then using the intensity ratio of MA and CA droplets under different RH to determine aerosol particle pH based on calibration curves. Results have shown that aerosol pH of MA droplet decreases with a decreasing RH and pH values ranges from 1.03 to -0.12, when RH value is reduced from 90% to 26%, in good agreement with model prediction values. In addition, we also, for the first time, report pH values of CA droplets under different RH conditions and its pH values range from 1.13 to -0.74 when RH is reduced from 91% to 28%.
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Affiliation(s)
- Pianpian Chang
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, PR China
| | - Zhe Chen
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, PR China
| | - Yunhong Zhang
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, PR China.
| | - Yong Liu
- Department of Chemistry, University of Colorado Denver, Denver, CO, 80217, USA.
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9
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Chang D, Wang Z, Guo J, Li T, Liang Y, Kang L, Xia M, Wang Y, Yu C, Yun H, Yue D, Wang T. Characterization of organic aerosols and their precursors in southern China during a severe haze episode in January 2017. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 691:101-111. [PMID: 31319248 DOI: 10.1016/j.scitotenv.2019.07.123] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/07/2019] [Accepted: 07/08/2019] [Indexed: 06/10/2023]
Abstract
The rapid industrialization and economic development in the Pearl River Delta (PRD) region of southern China have led to a substantial increase in anthropogenic emissions and hence frequent haze pollution over the past two decades. In early January 2017, a severe regional haze pollution episode was captured in the PRD region, with a peak PM2.5 concentration of around 400μgm-3, the highest value ever reported at this site. During the haze episode, elevated concentrations of oxygenated volatile organic compounds (OVOCs, 33±16 ppbv) and organic matter (41±15μg m-3) were observed, indicating the enhanced roles of secondary organic aerosols (SOAs) in the formation of haze pollution. Water-soluble organic carbon (WSOC, 12.8±5.5μg C m-3) dominated the organic aerosols, with a WSOC/OC ratio of 0.63±0.12 and high correlation (R=0.85) with estimated secondary organic carbon (SOC), suggesting the predominance of a secondary origin of the measured organic aerosols during the haze episode. Four carboxylic acids (oxalic, acetic, formic, and pyruvic acids) were characterized in the aerosols (1.30±0.38μgm-3) and accounted for 3.6±1.2% of WSOC in carbon mass, with oxalic acid as the most abundant species. The simultaneous measurements of volatile organic compounds (VOCs), OVOCs, and organic acids in aerosols at this site provided an opportunity to investigate the relationship between the precursors and the products, as well as the potential formation pathways. Water-soluble aldehydes and ketones, predominantly produced via the oxidation of anthropogenic VOCs (mainly propane, toluene, n-butane, and m, p-xylene), were the main contributors of the organic acids. The formation of OVOCs is largely attributed to gas-phase photochemical oxidation, whereas the WSOC and dicarboxylic acids were produced from both photochemistry and nocturnal heterogeneous reactions. These findings provided further insights into the oxidation and evolution of organic compounds during the haze pollution episode.
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Affiliation(s)
- Di Chang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Zhe Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
| | - Jia Guo
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Tao Li
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China; School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Yiheng Liang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Lingyan Kang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Men Xia
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Yaru Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Chuan Yu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China; School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Hui Yun
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Dingli Yue
- Guangdong Environmental Monitoring Center, State Environmental Protection Key Laboratory of Regional Air Quality Monitoring, Guangzhou 510308, China
| | - Tao Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
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10
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Requia WJ, Jhun I, Coull BA, Koutrakis P. Climate impact on ambient PM 2.5 elemental concentration in the United States: A trend analysis over the last 30 years. ENVIRONMENT INTERNATIONAL 2019; 131:104888. [PMID: 31302483 DOI: 10.1016/j.envint.2019.05.082] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/06/2019] [Accepted: 05/31/2019] [Indexed: 05/02/2023]
Abstract
Weather impacts on the chemical composition of PM2.5 varies significantly over space and time given the diversity of particle components and the complex mechanisms governing particle formation and removal. In this study, we employed generalized additive models (GAMs) to estimate weather-associated changes in PM2.5 composition in the US during 1988-2017. We considered seven components of ambient PM2.5, which included elemental carbon (EC), organic carbon (OC), nitrate, sulfate, sodium, ammonium, and silicon. The impact of long-term weather changes on each PM2.5 component was defined in our study as "weather penalty". During our study period, temperature increased in four regions, including the Industrial Midwest and Northeast during the warm and cold season; and Upper Midwest and West in the cold season. Wind speed decreased in the both seasons. Relative humidity increased in the warm season and decreased in the cold season. The weather changes between 1988 and 2017 were associated with most PM2.5 components during both warm and cold seasons. The direction and the magnitude of the weather penalty varied considerably over the space and season. In the warm season, our findings suggest a nationwide weather penalty for EC, OC, nitrate, sulfate, sodium, ammonium, and silicon of 0.04, 0.21, 0.04, 0.35, -0.01, 0.05, and 0.01 μg/m3, respectively. In the cold season, the estimated total penalty was 0.04, 0.21, 0.06, 0.04, -0.01, -0.02, and 0.02 μg/m3, respectively.
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Affiliation(s)
- Weeberb J Requia
- Harvard University, Department of Environmental Health, School of Public Health, Boston, MA, United States.
| | - Iny Jhun
- Harvard University, Harvard Medical School, Boston, MA, United States
| | - Brent A Coull
- Harvard University, Department of Biostatistics, School of Public Health, Boston, MA, United States
| | - Petros Koutrakis
- Harvard University, Department of Environmental Health, School of Public Health, Boston, MA, United States
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11
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Temporal Variation and Chemical Components of Rural Ambient PM2.5 during Main Agricultural Activity Periods in the Black Soil Region of Northeast China. ATMOSPHERE 2019. [DOI: 10.3390/atmos10090510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Agricultural emissions are crucial to regional air quality in the autumn and spring due to the intense agricultural activities in Northeast China. However, information on rural ambient particulate matter (PM) in Northeast China is rare, limiting the accurate estimation of agricultural atmospheric particulate matter emissions. In this study, we monitored hourly ambient PM2.5 (PM with a diameter of less than 2.5 μm) concentrations and analyzed daily chemical components (i.e., water-soluble ions, trace elements, organic carbon, and element carbon) at a rural site in Northeast China during the autumn and spring and assessed the impact of agricultural activities on atmospheric PM2.5 concentrations. The results showed that the daily average concentrations of PM2.5 were 143 ± 109 (range: 39–539) μg m−3 from 19 October to 23 November 2017 (i.e., typical harvesting month) and 241 ± 189 (range: 97–976) μg m−3 from 1 April to 13 May 2018 (i.e., typical tilling month). In autumn, the ambient PM2.5 concentrations were high with a Southwest wind, while a Southeast wind caused high PM2.5 concentrations during spring in the rural site. The concentrations of selected water-soluble ions, trace elements, and carbonaceous fractions accounted for 33%, 4%, and 26% of PM2.5 mass concentrations, respectively, in autumn and for 10%, 5%, and 3% of PM2.5 mass concentrations, respectively, in spring. On the basis of the component analysis, straw burning, agricultural machinery, and soil dust driven by wind and tilling were the main contributors to high rural PM2.5 concentrations. In addition, the increasing coal combustion around the rural site was another important source of PM2.5.
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12
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Li X, Song H, Zhai S, Lu S, Kong Y, Xia H, Zhao H. Particulate matter pollution in Chinese cities: Areal-temporal variations and their relationships with meteorological conditions (2015-2017). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 246:11-18. [PMID: 30529935 DOI: 10.1016/j.envpol.2018.11.103] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/14/2018] [Accepted: 11/29/2018] [Indexed: 06/09/2023]
Abstract
As the second largest economy in the world, China experiences severe particulate matter (PM) pollution in many of its cities. Meteorological factors are critical in determining both areal and temporal variations in PM pollution levels; understanding these factors and their interactions is critical for accurate forecasting, comprehensive analysis, and effective reduction of this pollution. This study analyzed areal and temporal variations in concentrations of PM2.5, PM10, and PMcoarse (PM10 - PM2.5) and PM2.5 to PM10 ratios (PM2.5/PM10) and their relationships with meteorological conditions in 366 Chinese cities from January 1, 2015 to December 31, 2017. On the national scale, PM2.5 and PM10 decreased from 48 to 42 μg m-³ and from 88 to 84 μg m-³, respectively, and the annual mean concentrations were 45 μg m-³ (PM2.5) and 84 μg m-³ (PM10) during the time period (2015-2017). In most regions, largest PM concentrations occurred in winter. However, in northern China, in spring PMcoarse concentrations were highest due to dust. The PM2.5/PM10 ratio was higher in southern than in northern China. There were large regional disparities in PM diurnal variations. Generally, PM concentrations were negatively correlated with precipitation, relative humidity, air temperature, and wind speed, but were positively correlated with surface pressure. The sunshine duration showed negative and positive impacts on PM in northern and southern cities, respectively. Meteorological factors impacted particulates of different size differently in different regions and over different periods of time.
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Affiliation(s)
- Xiaoyang Li
- Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, Henan University, Kaifeng, Henan, 475004, China
| | - Hongquan Song
- Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, Henan University, Kaifeng, Henan, 475004, China; Institute of Urban Big Data, College of Environment and Planning, Henan University, Kaifeng, Henan, 475004, China; Henan Key Laboratory of Integrated Air Pollution Control and Ecological Security, Henan University, Kaifeng, Henan, 475004, China.
| | - Shiyan Zhai
- Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, Henan University, Kaifeng, Henan, 475004, China; Institute of Urban Big Data, College of Environment and Planning, Henan University, Kaifeng, Henan, 475004, China
| | - Siqi Lu
- College of Plant Science, Jilin University, Changchun, Jilin, 130062, China
| | - Yunfeng Kong
- Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, Henan University, Kaifeng, Henan, 475004, China; Institute of Urban Big Data, College of Environment and Planning, Henan University, Kaifeng, Henan, 475004, China
| | - Haoming Xia
- Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, Henan University, Kaifeng, Henan, 475004, China
| | - Haipeng Zhao
- Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, Henan University, Kaifeng, Henan, 475004, China; Institute of Urban Big Data, College of Environment and Planning, Henan University, Kaifeng, Henan, 475004, China
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13
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Zong Z, Tan Y, Wang X, Tian C, Fang Y, Chen Y, Fang Y, Han G, Li J, Zhang G. Assessment and quantification of NO x sources at a regional background site in North China: Comparative results from a Bayesian isotopic mixing model and a positive matrix factorization model. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:1379-1386. [PMID: 30138830 DOI: 10.1016/j.envpol.2018.08.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 07/13/2018] [Accepted: 08/08/2018] [Indexed: 06/08/2023]
Abstract
Regional sources of nitrogen oxides (NOx) in North China during summer were explored using both a Bayesian isotopic mixing model and a positive matrix factorization (PMF) model. Results showed that the nitrogen isotope (δ15N) composition of particulate nitrate (NO3-) varied between -8.9‰ and +14.1‰, while the oxygen isotope (δ18O) composition ranged from +57.4‰ to +93.8‰. Based on results from the Bayesian isotopic mixing model, the contribution of the hydroxyl radical (•OH) NOx conversion pathway showed clear diurnal fluctuation; values were higher during the day (0.53 ± 0.16) and lower overnight (0.42 ± 0.17). Values peaked at 06:00-12:00 and then decreased gradually until 00:00-06:00 the next day. Coal combustion (31.34 ± 9.04%) was the most significant source of NOx followed by biomass burning (25.74 ± 2.58%), mobile sources (23.83 ± 3.66%), and microbial processes (19.09 ± 5.21%). PMF results indicated that the contribution from mobile sources was 19.83%, slightly lower as compared to the Bayesian model (23.83%). The PMF model also reported a lower contribution from coal combustion (28.65%) as compared to the Bayesian model (31.34%); however, the sum of biomass burning and microbial processes in the Bayesian model (44.83%) was lower than the aggregate of secondary inorganic aerosol, sea salt, and soil dust in PMF model (51.52%). Overall, differences between the two models were minor, suggesting that this study provided a reasonable source quantification for NOx in North China during summer.
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Affiliation(s)
- Zheng Zong
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Yang Tan
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
| | - Xiaoping Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Chongguo Tian
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China.
| | - Yunting Fang
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning, 110164, China
| | - Yingjun Chen
- Key Laboratory of Cities' Mitigation and Adaptation to Climate Change in Shanghai (CMA), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Yin Fang
- Key Laboratory of Cities' Mitigation and Adaptation to Climate Change in Shanghai (CMA), College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Guangxuan Han
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
| | - Jun Li
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
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14
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Liu W, Xu Y, Liu W, Liu Q, Yu S, Liu Y, Wang X, Tao S. Oxidative potential of ambient PM 2.5 in the coastal cities of the Bohai Sea, northern China: Seasonal variation and source apportionment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 236:514-528. [PMID: 29428706 DOI: 10.1016/j.envpol.2018.01.116] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/05/2018] [Accepted: 01/31/2018] [Indexed: 05/19/2023]
Abstract
Emissions of air pollutants from primary and secondary sources in China are considerably higher than those in developed countries, and exposure to air pollution is main risk of public health. Identifying specific particulate matter (PM) compositions and sources are essential for policy makers to propose effective control measures for pollutant emissions. Ambient PM2.5 samples covered a whole year were collected from three coastal cities of the Bohai Sea. Oxidative potential (OP) was selected as the indicator to characterize associated PM compositions and sources most responsible for adverse impacts on human health. Positive matrix factorization (PMF) and multiple linear regression (MLR) were employed to estimate correlations of PM2.5 sources with OP. The volume- and mass-based dithiothreitol (DTTv and DTTm) activities of PM2.5 were significantly higher in local winter or autumn (p < 0.01). Spatial and seasonal variations in DTTv and DTTm were much larger than mass concentrations of PM2.5, indicated specific chemical components are responsible for PM2.5 derived OP. Strong correlations (r > 0.700, p < 0.01) were found between DTT activity and water-soluble organic carbon (WSOC) and some transition metals. Using PMF, source fractions of PM2.5 were resolved as secondary source, traffic source, biomass burning, sea spray and urban dust, industry, coal combustion, and mineral dust. Further quantified by MLR, coal combustion, biomass burning, secondary sources, industry, and traffic source were dominant contributors to the water-soluble DTTv activity. Our results also suggested large differences in seasonal contributions of different sources to DTTv variability. A higher contribution of DTTv was derived from coal combustion during the local heating period. Secondary sources exhibited a greater fraction of DTTv in summer, when there was stronger solar radiation. Traffic sources exhibited a prevailing contribution in summer, and industry contributed larger proportions in spring and winter. Future abatement priority of air pollution should reduce the sources contributing to OP of PM2.5.
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Affiliation(s)
- WeiJian Liu
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - YunSong Xu
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - WenXin Liu
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China.
| | - QingYang Liu
- Collaborative Innovation Center of Sustainable Forestry in Southern China of Jiangsu Province, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China.
| | - ShuangYu Yu
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Yang Liu
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Xin Wang
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Shu Tao
- Key Laboratory for Earth Surface and Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
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15
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Yu M, Guo Z, Wang X, Eglinton TI, Yuan Z, Xing L, Zhang H, Zhao M. Sources and radiocarbon ages of aerosol organic carbon along the east coast of China and implications for atmospheric fossil carbon contributions to China marginal seas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 619-620:957-965. [PMID: 29734641 DOI: 10.1016/j.scitotenv.2017.11.201] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/27/2017] [Accepted: 11/17/2017] [Indexed: 06/08/2023]
Abstract
Aerosol deposition is an important mechanism for the delivery of terrestrial organic carbon (OC) to marginal seas, but OC age characteristics of aerosols are not well constrained and their contributions to sediment OC burial have not been quantified. Total suspended particle samples were collected along the east coast of China at Changdao (CD), Qingdao (QD) and Huaniao Island (HNI), and were analyzed for total organic carbon (TOC) isotopes (13C and 14C) in order to bridge this information gap. TOC δ13C and Δ14C values ranged from -23.6 to -30.5‰, and -153 to -687‰, respectively, with the latter corresponding to 14C ages ranging from 1280 to 9260yr. Estimated contributions of fossil carbon to TOC based on 14C mass balance approach ranged from 26 to 73%, with strong seasonal variations in fossil carbon observed at CD. Fossil carbon at CD showed the highest proportion (73%) in winter, reflecting anthropogenic emissions and the lowest proportion (26%) in summer, caused by biomass contribution (annual ave., 52%±17%). In contrast, the fossil carbon at both QD (57-64%) and HNI (57-67%) dominated throughout the year, reflecting local anthropogenic influences and long-range transport. Mass balance estimates indicate that atmospheric deposition and riverine export accounted for 31% and 69% of fossil carbon inputs to the China marginal seas (CMS) respectively, with fossil carbon burial efficiencies approaching 100% in the CMS. On a global scale, an atmospheric fossil carbon deposition flux of 17.2TgCyr-1 was estimated, equivalent to 40% of the estimated fluvial flux to the ocean, and potentially accounting for 24-41% of fossil OC burial in marine sediments. Therefore, the atmospheric deposition constitutes an important source of fossil carbon to marine sediments, and could play a key role in regional and global scale OC budgets and biogeochemical cycles.
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Affiliation(s)
- Meng Yu
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Zhigang Guo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Fudan University, Shanghai, China
| | - Xuchen Wang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China
| | - Timothy Ian Eglinton
- Geological Institute, Department of Earth Sciences, ETH Zürich, 8092 Zürich, Switzerland
| | - Zineng Yuan
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China
| | - Lei Xing
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China
| | - Hailong Zhang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China
| | - Meixun Zhao
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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16
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Craig RL, Nandy L, Axson JL, Dutcher CS, Ault AP. Spectroscopic Determination of Aerosol pH from Acid–Base Equilibria in Inorganic, Organic, and Mixed Systems. J Phys Chem A 2017; 121:5690-5699. [DOI: 10.1021/acs.jpca.7b05261] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
| | - Lucy Nandy
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | | | - Cari S. Dutcher
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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17
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Singh A, Rastogi N, Patel A, Singh D. Seasonality in size-segregated ionic composition of ambient particulate pollutants over the Indo-Gangetic Plain: Source apportionment using PMF. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 219:906-915. [PMID: 27622841 DOI: 10.1016/j.envpol.2016.09.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 09/02/2016] [Accepted: 09/04/2016] [Indexed: 05/21/2023]
Abstract
Size-segregated particulate pollutants (PM<0.95, PM0.95-1.5, PM1.5-3.0, PM3.0-7.2 and PM>7.2) were collected over Patiala (30.33°N, 76.40°E; 250 m amsl), a semi-urban city located in northwestern Indo-Gangetic Plain (IGP), during October, 2012 to September, 2013. Mass concentration of total suspended particulates (TSP), derived by summation of particulate (aerosol) mass in different size range, varied from 88 to 387 μg m-3 with highest mass concentration (∼55% of total mass) in submicron size (PM<0.95) during the entire study period, which broadly reflects relative higher contribution of various anthropogenic sources (emissions from biomass and bio-fuel burning, vehicles, thermal power plants, etc) to ambient particles. Concentration of SO42-, NO3-, NH4+, K+ and Ca2+ exhibited large variability ranging from 0.52 to 40, 0.20 to 19, 0.14 to 12, 0.06 to 5.3 and 0.08 to 5.6 μg m-3, respectively, in different size ranges with varying size distribution for most of the species, except NH4+. A strong linear correlation (r = 0.97) between (SO42- + NO3-) and (K+ + NH4+) concentrations has been observed in submicron particles collected in different seasons, suggesting the formation of secondary inorganic salts. However, relatively poor correlation is observed in higher size ranges where significant correlation between (SO42- + NO3-) and (Ca2+ + Mg2+) has been observed. These observations indicate the acid neutralization by dust in coarser modes of particles. Chemical composition of submicron particulates (PM<0.95) in different seasons as well as for whole year was used to identify PM sources through the application of Positive Matrix Factorization (PMF, version 5.0) model. Based on annual data, PMF analyses suggests that six source factors namely biomass burning emission (24%), vehicular emission (22%), secondary organic aerosols (20%), power plant emission (13%), secondary inorganic aerosols (12%) and mineral dust (9%) contribute to PM<0.95 loading over the study region. Such studies are important in dispersion modeling, health impact assessment, and planning of pollution mitigation strategies.
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Affiliation(s)
- Atinderpal Singh
- Department of Physics, Punjabi University, Patiala, Punjab, India.
| | - Neeraj Rastogi
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat, India
| | - Anil Patel
- Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat, India
| | - Darshan Singh
- Department of Physics, Punjabi University, Patiala, Punjab, India
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18
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Fu P, Aggarwal SG, Chen J, Li J, Sun Y, Wang Z, Chen H, Liao H, Ding A, Umarji GS, Patil RS, Chen Q, Kawamura K. Molecular Markers of Secondary Organic Aerosol in Mumbai, India. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:4659-4667. [PMID: 27045808 DOI: 10.1021/acs.est.6b00372] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Biogenic secondary organic aerosols (SOA) are generally considered to be more abundant in summer than in winter. Here, polar organic marker compounds in urban background aerosols from Mumbai were measured using gas chromatography-mass spectrometry. Surprisingly, we found that concentrations of biogenic SOA tracers at Mumbai were several times lower in summer (8-14 June 2006; wet season; n = 14) than in winter (13-18 February 2007; dry season; n = 10). Although samples from less than 10% of the season are extrapolated to the full season, such seasonality may be explained by the predominance of the southwest summer monsoon, which brings clean marine air masses to Mumbai. While heavy rains are an important contributor to aerosol removal during the monsoon season, meteorological data (relative humidity and T) suggest no heavy rains occurred during our sampling period. However, in winter, high levels of SOA and their day/night differences suggest significant contributions of continental aerosols through long-range transport together with local sources. The winter/summer pattern of SOA loadings was further supported by results from chemical transport models (NAQPMS and GEOS-Chem). Furthermore, our study suggests that monoterpene- and sesquiterpene-derived secondary organic carbon (SOC) were more significant than those of isoprene- and toluene-SOC at Mumbai.
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Affiliation(s)
- Pingqing Fu
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
- Institute of Low Temperature Science, Hokkaido University , Sapporo 060-0819, Japan
| | - Shankar G Aggarwal
- Institute of Low Temperature Science, Hokkaido University , Sapporo 060-0819, Japan
- CSIR-National Physical Laboratory, New Delhi 110012, India
| | - Jing Chen
- SKLEG, Institute of Geochemistry, Chinese Academy of Sciences , Guiyang 550081, China
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences , Beijing 100101, China
| | - Jie Li
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
| | - Yele Sun
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
| | - Zifa Wang
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
| | - Huansheng Chen
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
| | - Hong Liao
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences , Beijing 100029, China
- School of Environmental Science and Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China
| | - Aijun Ding
- Institute for Climate and Global Change Research & School of Atmospheric Sciences, Nanjing University , Nanjing, 210093, China
| | - G S Umarji
- Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay , Mumbai, 400076, India
| | - R S Patil
- Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay , Mumbai, 400076, India
| | - Qi Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University , Beijing 100871, China
| | - Kimitaka Kawamura
- Institute of Low Temperature Science, Hokkaido University , Sapporo 060-0819, Japan
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19
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Rindelaub JD, Craig RL, Nandy L, Bondy AL, Dutcher CS, Shepson PB, Ault AP. Direct Measurement of pH in Individual Particles via Raman Microspectroscopy and Variation in Acidity with Relative Humidity. J Phys Chem A 2016; 120:911-7. [PMID: 26745214 DOI: 10.1021/acs.jpca.5b12699] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atmospheric aerosol acidity is an important characteristic of aqueous particles, which has been linked to the formation of secondary organic aerosol by catalyzing reactions of oxidized organic compounds that have partitioned to the particle phase. However, aerosol acidity is difficult to measure and traditionally estimated using indirect methods or assumptions based on composition. Ongoing disagreements between experiments and thermodynamic models of particle acidity necessitate improved fundamental understanding of pH and ion behavior in high ionic strength atmospheric particles. Herein, Raman microspectroscopy was used to determine the pH of individual particles (H2SO4+MgSO4) based on sulfate and bisulfate concentrations determined from νs(SO4(2-)) and νs(HSO4(-)), the acid dissociation constant, and activity coefficients from extended Debye-Hückel calculations. Shifts in pH and peak positions of νs(SO4(2-)) and νs(HSO4(-)) were observed as a function of relative humidity. These results indicate the potential for direct spectroscopic determination of pH in individual particles and the need to improve fundamental understanding of ion behavior in atmospheric particles.
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Affiliation(s)
- Joel D Rindelaub
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Rebecca L Craig
- Department of Chemistry, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Lucy Nandy
- Department of Mechanical Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Amy L Bondy
- Department of Chemistry, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Cari S Dutcher
- Department of Mechanical Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Paul B Shepson
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States.,Department of Earth, Atmospheric, and Planetary Sciences, Purdue University , West Lafayette, Indiana 47907, United States.,Purdue Climate Change Research Center , West Lafayette, Indiana 47907, United States
| | - Andrew P Ault
- Department of Chemistry, University of Michigan , Ann Arbor, Michigan 48109, United States.,Department of Environmental Health Sciences, University of Michigan , Ann Arbor, Michigan 48109, United States
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Spatial and temporal variation in fine particulate matter mass and chemical composition: the Middle East Consortium for Aerosol Research Study. ScientificWorldJournal 2014; 2014:878704. [PMID: 25045751 PMCID: PMC4090475 DOI: 10.1155/2014/878704] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 05/24/2014] [Indexed: 11/17/2022] Open
Abstract
Ambient fine particulate matter (PM2.5) samples were collected from January to December 2007 to investigate the sources and chemical speciation in Palestine, Jordan, and Israel. The 24-h PM2.5 samples were collected on 6-day intervals at eleven urban and rural sites simultaneously. Major chemical components including metals, ions, and organic and elemental carbon were analyzed. The mass concentrations of PM2.5 across the 11 sites varied from 20.6 to 40.3 μg/m3, with an average of 28.7 μg/m3. Seasonal variation of PM2.5 concentrations was substantial, with higher average concentrations (37.3 μg/m3) in the summer (April–June) months compared to winter (October–December) months (26.0 μg/m3) due mainly to high contributions of sulfate and crustal components. PM2.5 concentrations in the spring were greatly impacted by regional dust storms. Carbonaceous mass was the most abundant component, contributing 40% to the total PM2.5 mass averaged across the eleven sites. Crustal components averaged 19.1% of the PM2.5 mass and sulfate, ammonium, and nitrate accounted for 16.2%, 6.4%, and 3.7%, respectively, of the total PM2.5 mass. The results of this study demonstrate the need to better protect the health and welfare of the residents on both sides of the Jordan River in the Middle East.
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Wang X, Chen Y, Tian C, Huang G, Fang Y, Zhang F, Zong Z, Li J, Zhang G. Impact of agricultural waste burning in the Shandong Peninsula on carbonaceous aerosols in the Bohai Rim, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 481:311-316. [PMID: 24607395 DOI: 10.1016/j.scitotenv.2014.02.064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/11/2014] [Accepted: 02/15/2014] [Indexed: 06/03/2023]
Abstract
A total of 11 5PM2.5 samples were collected for analyzing organic carbon (OC) and elemental carbon (EC) at Tuoji Island (TI), China from November 2011 to December 2012. The results showed that annual arithmetical means of OC and EC concentrations were 3.8 ± 2.7 and 2.2 ± 2.2 μg m(-3), which contributed 8% and 4% of PM2.5 mass concentrations, respectively. High EC concentrations occurred in winter, contributed mainly by EC outflow from the northwest source region, while high OC concentrations were found during spring, attributed largely to biofuel burning in the Shandong Peninsula, and short distance and favorable transport from the peninsula to the TI. Agricultural waste open burning in the peninsula caused the largest variability of OC concentration in summer. Eliminating agricultural field burning in the peninsula can reduce at least one-third of concentration levels and half of northward transport fluxes of OC and EC in Bohai Rim in summer.
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Affiliation(s)
- Xiaoping Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
| | - Yingjun Chen
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
| | - Chongguo Tian
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Guopei Huang
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Yin Fang
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Fan Zhang
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Zheng Zong
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Jun Li
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
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Rastogi N, Singh A, Singh D, Sarin MM. Chemical characteristics of PM(2.5) at a source region of biomass burning emissions: evidence for secondary aerosol formation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2014; 184:563-569. [PMID: 24184378 DOI: 10.1016/j.envpol.2013.09.037] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/24/2013] [Accepted: 09/26/2013] [Indexed: 06/02/2023]
Abstract
A systematic study on the chemical characteristics of ambient PM2.5, collected during October-2011 to March-2012 from a source region (Patiala: 30.2°N, 76.3°E; 250 m amsl) of biomass burning emissions in the Indo-Gangetic Plain (IGP), exhibit pronounced diurnal variability in mass concentrations of PM2.5, NO3(-), NH4(+), K(+), OC, and EC with ~30-300% higher concentrations in the nighttime samples. The average WSOC/OC and SO4(2-)/PM2.5 ratios for the daytime (~0.65, and 0.18, respectively) and nighttime (0.45, and 0.12, respectively) samples provide evidence for secondary organic and SO4(2-) aerosol formation during the daytime. Formation of secondary NO3(-) is also evident from higher NH4NO3 concentrations associated with lower temperature and higher relative humidity conditions. The scattering species (SO4(2-) + NO3(-) + OC) contribute ~50% to PM2.5 mass during October-March whereas absorbing species (EC) contribute only ~4% in October-February and subsequently increases to ~10% in March, indicating significance of these species in regional radiative forcing.
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Affiliation(s)
- N Rastogi
- Geosciences Division, Physical Research Laboratory, Navrangpura, Ahmedabad 380009, India.
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Pan XL, Kanaya Y, Wang ZF, Taketani F, Tanimoto H, Irie H, Takashima H, Inomata S. Emission ratio of carbonaceous aerosols observed near crop residual burning sources in a rural area of the Yangtze River Delta Region, China. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd018357] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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