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Targino AC, Moreno FL, Krecl P, Cardoso JV. Significant differences in black and brown carbon concentrations at urban and suburban sites. Heliyon 2023; 9:e18418. [PMID: 37520949 PMCID: PMC10374922 DOI: 10.1016/j.heliyon.2023.e18418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/16/2023] [Accepted: 07/17/2023] [Indexed: 08/01/2023] Open
Abstract
Light-absorbing carbonaceous particles (LAC) may cause and/or exacerbate non-communicable diseases, interfere with the Earth's radiative balance, darken urban buildings and impair vistas. In this study, we explored the temporal behaviour of LAC concentrations measured at wavelengths of 370 nm (brown carbon, BrC) and 880 nm (black carbon, BC) at two sites of a mid-sized city in Brazil. We observed sharp changes in LAC concentrations at the city centre site in response to variations in traffic volume. The highest concentrations were observed when winds originated from both the city core and from the direction of the bus terminal. The suburban site exhibited a notably uniform diurnal pattern and consistently lower LAC concentrations throughout the day. Nevertheless, substantial increases during the evening led to mean BrC and BC concentrations (2.6 and 2.2 μg m-3, respectively) comparable to daytime peaks observed in the city centre (3 μg m-3 and 2.5 μg m-3). This phenomenon was attributed to the burning of residential waste and overgrown vegetation in nearby vacant lots. Moreover, the highest concentrations coincided with periods of low wind speeds, usually linked to non-buoyant plumes from point sources. BrC concentrations surpassed BC concentrations, even at the city centre site. Not only was the Ångström absorption exponent (Å370/880) larger at the suburban site compared to the city centre (95th percentiles of 1.73 and 1.38, respectively), but it also exhibited a wider span. Overall, the combined LAC and Å370/880 data indicated that i) biomass burning is a major source of LAC at the suburban site; ii) at the city centre, bare BC particles may become internally mixed with BrC from biomass or fossil fuel emissions and enhance absorption at lower wavelengths. The occurrence of LAC peaks outside the evening rush hours suggests that other sources but on-road vehicular emissions may contribute to the deterioration of the air quality in the urban core. Tackling air quality across the urban perimeter requires targeting other potential sources but traffic emissions.
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Ceolato R, Bedoya-Velásquez AE, Fossard F, Mouysset V, Paulien L, Lefebvre S, Mazzoleni C, Sorensen C, Berg MJ, Yon J. Black carbon aerosol number and mass concentration measurements by picosecond short-range elastic backscatter lidar. Sci Rep 2022; 12:8443. [PMID: 35589746 PMCID: PMC9120489 DOI: 10.1038/s41598-022-11954-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 04/19/2022] [Indexed: 11/21/2022] Open
Abstract
Black carbon aerosol emissions are recognized as contributors to global warming and air pollution. There remains, however, a lack of techniques to remotely measure black carbon aerosol particles with high range and time resolution. This article presents a direct and contact-free remote technique to estimate the black carbon aerosol number and mass concentration at a few meters from the emission source. This is done using the Colibri instrument based on a novel technique, referred to here as Picosecond Short-Range Elastic Backscatter Lidar (PSR-EBL). To address the complexity of retrieving lidar products at short measurement ranges, we apply a forward inversion method featuring radiometric lidar calibration. Our method is based on an extension of a well-established light-scattering model, the Rayleigh-Debye-Gans for Fractal-Aggregates (RDG-FA) theory, which computes an analytical expression of lidar parameters. These parameters are the backscattering cross-sections and the lidar ratio for black carbon fractal aggregates. Using a small-scale Jet A-1 kerosene pool fire, we demonstrate the ability of the technique to quantify the aerosol number and mass concentration with centimetre range-resolution and millisecond time-resolution.
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Affiliation(s)
- Romain Ceolato
- ONERA, The French Aerospace Lab, Toulouse University, 31055, Toulouse, France.
| | | | - Frédéric Fossard
- ONERA, The French Aerospace, Paris-Saclay University, CNRS, Laboratoire d'étude des microstructures, 92322, Châtillon, France
| | - Vincent Mouysset
- ONERA, The French Aerospace Lab, Toulouse University, 31055, Toulouse, France
| | - Lucas Paulien
- ONERA, The French Aerospace Lab, Toulouse University, 31055, Toulouse, France
| | | | - Claudio Mazzoleni
- Physics Department, Michigan Technological University, Houghton, MI, USA
| | - Christopher Sorensen
- Department of Physics, Kansas State University, 1228 N. 17th St., Manhattan, KS, 66506-2601, USA
| | - Matthew J Berg
- Department of Physics, Kansas State University, 1228 N. 17th St., Manhattan, KS, 66506-2601, USA
| | - Jérôme Yon
- CNRS, CORIA, INSA Rouen, UNIROUEN, Normandie University, 76000, Rouen, France
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Characteristics and Aging of Traffic-Emitted Particles with Sulfate and Organic Compound Formation in Urban Air. ATMOSPHERE 2022. [DOI: 10.3390/atmos13040608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Traffic is a major source of anthropogenic aerosol in urban atmosphere. In this study, aerosol particles were measured with a TEM-EDX system at the roadside of a main road in the northwestern part of Beijing, China, under clear and hazy conditions. Soot, organic, sulfur-rich (S-rich), mineral, and metal particles, as well as the mixtures, were frequently encountered in aerosols. Under hazy conditions, S-rich particles coated with organic matter (S-OM particles) accounted for most of the total particles (15% to 24%), followed by soot particles (18% to 21%), organic particles (17% to 21%), non-mixed S-rich particles (10% to 18%), and S-rich particles with soot-, mineral-, or metal-inclusions (here referred to as S-inclusion particles) (11% to 15%). Under clear conditions, non-mixed S-rich and organic particles were dominant components, while mineral and soot particles were secondary components, among which, ~14% of the total particles had a sulfate core or OM coating; inclusions of mixture particles were often mixed with sulfate cores. In the sulfate core–OM shell structure particles, the ratio of core diameter to the whole particle diameter was ~0.52 under hazy conditions and ~0.60 under clear conditions, indicating a substantial sulfate and organic formation on the particles. Soot particles accounted for 18% to 21% of the total particles. The relative growth of aged soot particles was higher under hazy conditions than under clear conditions. In sum, particles from traffic emissions on a main urban road aged with the formation of sulfate and organic matter.
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Su R, Jin X, Zhao W, Wu X, Zhai F, Li Z. Rutin ameliorates the promotion effect of fine particulate matter on vascular calcification in calcifying vascular cells and ApoE -/- mice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 234:113410. [PMID: 35279519 DOI: 10.1016/j.ecoenv.2022.113410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 03/05/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
Atmospheric PM2.5 exposure greatly contributes to the incidence of and mortality from cardiovascular disease (CVD). Owing to the crucial role of vascular calcification in the progression of CVD, it is imperative to elucidate the effects of PM2.5 on vascular calcification to understand the toxic mechanisms of haze-induced CVD. However, the effects of PM2.5 exposure on vascular calcification and the underlying molecular mechanisms are still unclear. In this work, the in vitro and in vivo models were used to illuminate the effects of PM2.5 on vascular calcification. We found that PM2.5 promoted the deposition of hydroxyapatite in calcifying vascular cells. Moreover, hydroxyapatite deposition was significantly enhanced by 3.5 times compared with those in the control group in aortas of ApoE-/- mice after exposure winter PM2.5 (1.5 mg/kg b.w.), accompanied by activation of the OPG/RANKL pathway and inflammatory cytokines' expressions. Moreover, PM2.5-induced reactive oxygen species (ROS) generation was observed. NAC, an ROS inhibitor, observably alleviated the promotion effects of PM2.5 on vascular calcification. Furthermore, rutin effectively prevented vascular calcification by regulating the OPG/RANKL pathway. Our results suggest that PM2.5 play an important role in the occurrence and development of vascular calcification, and that rutin has an antagonistic effect on it.
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Affiliation(s)
- Ruijun Su
- Department of Biology, Taiyuan Normal University, Taiyuan 030619, China
| | - Xiaoting Jin
- School of Public Health, Qingdao University, Qingdao 266071, China
| | - Wenjing Zhao
- Department of Biology, Taiyuan Normal University, Taiyuan 030619, China
| | - Xiaoying Wu
- Department of Biology, Taiyuan Normal University, Taiyuan 030619, China
| | - Feihong Zhai
- Department of Biology, Taiyuan Normal University, Taiyuan 030619, China
| | - Zhuoyu Li
- Institutes of Biomedical Sciences, Shanxi University, Taiyuan 030006, China; Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China.
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Su B, Zhang G, Zhuo Z, Xie Q, Du X, Fu Y, Wu S, Huang F, Bi X, Li X, Li L, Zhou Z. Different characteristics of individual particles from light-duty diesel vehicle at the launching and idling state by AAC-SPAMS. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126304. [PMID: 34329016 DOI: 10.1016/j.jhazmat.2021.126304] [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: 03/11/2021] [Revised: 05/15/2021] [Accepted: 05/31/2021] [Indexed: 06/13/2023]
Abstract
The rapid development of cities and economic prosperity greatly motivates the growth of vehicular exhaust particles, especially the diesel-exhausted particles from the large fleet of passenger and freight, which present profound implications on climate, air quality, and biological health (e.g., pulmonary, autoimmune and cardiovascular diseases). As important physiochemical properties of atmospheric aerosols, however, the mixing state and effective density of individual particles emitted from diesel-powered vehicles under different driving conditions and their environmental implications remain uncertain. Here, a single-particle aerosol mass spectrometer (SPAMS) was used to investigate the chemical composition and vacuum aerodynamic diameter (Dva), along with the aerodynamic diameter (Da) from an aerodynamic aerosol classifier (AAC), to determine the effective density of primary particles emitted from a light- duty diesel vehicle (LDDV) under the launching and idling engine states. Interestingly, the particle types and effective density appear to vary significantly with the engine status. A single particle type of Ca-rich particles, named Na-Ca-PAH, was predominant in the idling state, whose chemical components may be affected by the lubricants and incomplete combustion, contributing to a higher effective density (0.66 ± 0.21 g cm-3). In contrast, launching particles exhibited a lower effective density (0.34 ± 0.17 g cm-3) because of the substantial elemental carbon (EC). In addition, the effective density depends not only on the particle size but also on the chemical components with various abundances. EC and Ca play opposite roles in the effective density of LDDV emissions. Notably, a higher proportion of polycyclic aromatic hydrocarbons (PAHs) was observed in the idling particles, contributing to 78 ± 1.2%. Given the high contribution to these PAH-containing particles in the idling state, indispensable precautions should be taken at bus stops or waiting for pedestrians. This study provides more comprehensive insights into the initial characteristics of LDDV particles due to the launching and idling states, which is beneficial for improving the model results of source apportionment and understanding its environmental behavior regarding human health.
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Affiliation(s)
- Bojiang Su
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
| | - Guohua Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou 510640, PR China
| | - Zeming Zhuo
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
| | - Qinhui Xie
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
| | - Xubing Du
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
| | - YuZhen Fu
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Si Wu
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
| | - Fugui Huang
- Guangzhou Hexin Analytical Instrument Limited Company, Guangzhou 510530, PR China
| | - Xinhui Bi
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou 510640, PR China
| | - Xue Li
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
| | - Lei Li
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China.
| | - Zhen Zhou
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, PR China
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Ott EJE, Kucinski TM, Dawson JN, Freedman MA. Use of Transmission Electron Microscopy for Analysis of Aerosol Particles and Strategies for Imaging Fragile Particles. Anal Chem 2021; 93:11347-11356. [PMID: 34370455 DOI: 10.1021/acs.analchem.0c05225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
For over 25 years, transmission electron microscopy (TEM) has provided a method for the study of aerosol particles with sizes from below the optical diffraction limit to several microns, resolving the particles as well as smaller features. The wide use of this technique to study aerosol particles has contributed important insights about environmental aerosol particle samples and model atmospheric systems. TEM produces an image that is a 2D projection of aerosol particles that have been impacted onto grids and, through associated techniques and spectroscopies, can contribute additional information such as the determination of elemental composition, crystal structure, and 3D particle structures. Soot, mineral dust, and organic/inorganic particles have all been analyzed using TEM and spectroscopic techniques. TEM, however, has limitations that are important to understand when interpreting data including the ability of the electron beam to damage and thereby change the structure and shape of particles, especially in the case of particles composed of organic compounds and salts. In this paper, we concentrate on the breadth of studies that have used TEM as the primary analysis technique. Another focus is on common issues with TEM and cryogenic-TEM. Insights for new users on best practices for fragile particles, that is, particles that are easily susceptible to damage from the electron beam, with this technique are discussed. Tips for readers on interpreting and evaluating the quality and accuracy of TEM data in the literature are also provided and explained.
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Affiliation(s)
- Emily-Jean E Ott
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Theresa M Kucinski
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Joseph Nelson Dawson
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Miriam Arak Freedman
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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7
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Granum B, Oftedal B, Agier L, Siroux V, Bird P, Casas M, Warembourg C, Wright J, Chatzi L, de Castro M, Donaire D, Grazuleviciene R, Småstuen Haug L, Maitre L, Robinson O, Tamayo-Uria I, Urquiza J, Nieuwenhuijsen M, Slama R, Thomsen C, Vrijheid M. Multiple environmental exposures in early-life and allergy-related outcomes in childhood. ENVIRONMENT INTERNATIONAL 2020; 144:106038. [PMID: 32854059 PMCID: PMC8768577 DOI: 10.1016/j.envint.2020.106038] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/10/2020] [Accepted: 08/03/2020] [Indexed: 05/15/2023]
Abstract
INTRODUCTION Early onset and high prevalence of allergic diseases result in high individual and socio-economic burdens. Several studies provide evidence for possible effects of environmental factors on allergic diseases, but these are mainly single-exposure studies. The exposome provides a novel holistic approach by simultaneously studying a large set of exposures. The aim of the study was to evaluate the association between a broad range of prenatal and childhood environmental exposures and allergy-related outcomes in children. MATERIAL AND METHODS Analyses of associations between 90 prenatal and 107 childhood exposures and allergy-related outcomes (last 12 months: rhinitis and itchy rash; ever: doctor-diagnosed eczema and food allergy) in 6-11 years old children (n = 1270) from the European Human Early-Life Exposome cohort were performed. Initially, we used an exposome-wide association study (ExWAS) considering the exposures independently, followed by a deletion-substitution-addition selection (DSA) algorithm considering all exposures simultaneously. All the exposure variables selected in the DSA were included in a final multi-exposure model using binomial general linear model (GLM). RESULTS In ExWAS, no exposures were associated with the outcomes after correction for multiple comparison. In multi-exposure models for prenatal exposures, lower distance of residence to nearest road and higher di-iso-nonyl phthalate level were associated with increased risk of rhinitis, and particulate matter absorbance (PMabs) was associated with a decreased risk. Furthermore, traffic density on nearest road was associated with increased risk of itchy rash and diethyl phthalate with a reduced risk. DSA selected no associations of childhood exposures, or between prenatal exposures and eczema or food allergy. DISCUSSION This first comprehensive and systematic analysis of many environmental exposures suggests that prenatal exposure to traffic-related variables, PMabs and phthalates are associated with rhinitis and itchy rash.
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Affiliation(s)
- Berit Granum
- Norwegian Institute of Public Health, Oslo, Norway.
| | | | - Lydiane Agier
- Team of Environmental Epidemiology, IAB, Institute for Advanced Biosciences, Inserm, CNRS, CHU-Grenoble-Alpes, University Grenoble-Alpes, Grenoble, France
| | - Valerie Siroux
- Team of Environmental Epidemiology, IAB, Institute for Advanced Biosciences, Inserm, CNRS, CHU-Grenoble-Alpes, University Grenoble-Alpes, Grenoble, France
| | - Philippa Bird
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford UK
| | - Maribel Casas
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Charline Warembourg
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - John Wright
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford UK
| | - Leda Chatzi
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, USA; Department of Social Medicine, University of Crete, Greece; Department of Genetics & Cell Biology, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Montserrat de Castro
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - David Donaire
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Regina Grazuleviciene
- Department of Environmental Sciences, Vytauto Didziojo Universitetas, Kaunas, Lithuania
| | | | - Lea Maitre
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Oliver Robinson
- ISGlobal, Barcelona, Spain; MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, United Kingdom
| | | | | | - Mark Nieuwenhuijsen
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Remy Slama
- Team of Environmental Epidemiology, IAB, Institute for Advanced Biosciences, Inserm, CNRS, CHU-Grenoble-Alpes, University Grenoble-Alpes, Grenoble, France
| | | | - Martine Vrijheid
- ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
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The Ångström Exponent and Single-Scattering Albedo of Black Carbon: Effects of Different Coating Materials. ATMOSPHERE 2020. [DOI: 10.3390/atmos11101103] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In this work, the absorption Ångström exponent (AAE), extinction Ångström exponent (EAE), and single-scattering albedo (SSA) of black carbon (BC) with different coating materials are numerically investigated. BC with different coating materials can provide explanations for the small AAE, small EAE, and large AAE observed in the atmosphere, which is difficult to be explained by bare BC aggregate models. The addition of organic carbon (OC) does not necessarily increase AAE due to the transformation of BC morphologies and the existence of non-absorbing OC. The addition of coating materials does also not necessarily decrease EAE. While the addition of coating materials can increase the total size of BC-containing particles, the effective refractive index can be modified by introducing the coating materials, so increases the EAE. We found that it is not possible to differentiate between thinly- and heavily-coated BC based on EAE or AAE alone. On the other hand, SSA is much less sensitive to the size and can provide much more information for distinguishing heavily-coated BC from thinly-coated BC. For BC with different coating materials and mixing states, AAE, EAE, and SSA show rather different sensitivities to particle size and composition ratios, and their spectral-dependences also exhibit distinct differences. Different AAE and EAE trends with BC/OC ratio were also found for BC with different coating materials and mixing states. Furthermore, we also found empirical fittings for AAE, EAE, SSA, and optical cross-sections, which may be useful for retrieving the size information based on the optical measurements.
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Liu L, Mishchenko MI. Modeling study of scattering and absorption properties of tar-ball aggregates. APPLIED OPTICS 2019; 58:8648-8657. [PMID: 31873356 DOI: 10.1364/ao.58.008648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 10/08/2019] [Indexed: 06/10/2023]
Abstract
Atmospheric tar balls (TBs) form an important class of atmospheric brown carbon (BrC) particulates. The morphology of the individual TBs is typically described as amorphous and nearly spherical. However, several studies reported observations of TBs aggregated with other aerosols or agglomerations consisting of up to tens of individual TBs. We use the superposition $T$T-matrix method to compute the scattering matrix elements and optical cross sections for a variety of TB aggregates, each of which is composed of a number of monomers whose sizes follow a lognormal distribution. The results for a TB aggregate can differ fundamentally from those calculated for two simplified models commonly used in climate modeling; viz., the external mixture of TBs and the respective volume-equivalent sphere model. Clustering of individual TBs into an aggregate can either enhance or weaken absorption depending on the wavelength, the monomer size, and how absorptive the BrC material is. In the case of strongly absorptive BrC, aggregation results in enhanced absorption only at 1064 nm, while at 355 and 532 nm TB aggregates become less effective absorbers relative to the corresponding external mixtures. The effect of aggregation is always to increase the single-scattering albedo and asymmetry parameter, sometimes more than tenfold. The significant scattering-matrix differences between a TB aggregate, the "equivalent" external mixture, and the volume-equivalent sphere model demonstrate the failure of the conventional Lorenz-Mie theory to represent the scattering properties of morphologically complex BrC aerosols. We show that TB aggregates can help explain exceptionally strong and spectrally dependent lidar depolarization ratios reported in several recent studies.
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10
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Bhandari J, China S, Chandrakar KK, Kinney G, Cantrell W, Shaw RA, Mazzoleni LR, Girotto G, Sharma N, Gorkowski K, Gilardoni S, Decesari S, Facchini MC, Zanca N, Pavese G, Esposito F, Dubey MK, Aiken AC, Chakrabarty RK, Moosmüller H, Onasch TB, Zaveri RA, Scarnato BV, Fialho P, Mazzoleni C. Extensive Soot Compaction by Cloud Processing from Laboratory and Field Observations. Sci Rep 2019; 9:11824. [PMID: 31413342 PMCID: PMC6694138 DOI: 10.1038/s41598-019-48143-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/29/2019] [Indexed: 11/09/2022] Open
Abstract
Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models.
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Affiliation(s)
- Janarjan Bhandari
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA.
| | - Swarup China
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Kamal Kant Chandrakar
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
| | - Greg Kinney
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
| | - Will Cantrell
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
| | - Raymond A Shaw
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
| | - Lynn R Mazzoleni
- Atmospheric Sciences Program and Department of Chemistry, Michigan Technological University, Houghton, MI, USA
| | - Giulia Girotto
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
| | - Noopur Sharma
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Kyle Gorkowski
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA
- Atmospheric and Oceanic Sciences, McGill University, Montreal, Canada
- Earth & Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | | | - Stefano Decesari
- Institute of Atmospheric Sciences and Climate (CNR-ISAC), Rome, Italy
| | | | - Nicola Zanca
- Institute of Atmospheric Sciences and Climate (CNR-ISAC), Rome, Italy
- Department of Chemistry and Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Helsinki, Finland
| | - Giulia Pavese
- Institute of Methodologies for Environmental Analysis (CNR-IMAA), Rome, Italy
| | | | - Manvendra K Dubey
- Earth & Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Allison C Aiken
- Earth & Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Rajan K Chakrabarty
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | | | | | - Rahul A Zaveri
- Pacific Northwest National Laboratory, Richland, WA, USA
| | | | - Paulo Fialho
- Instituto de Investigação em Vulcanologia e Avaliação de Riscos - IVAR, University of Azores, Azores, Portugal
| | - Claudio Mazzoleni
- Atmospheric Sciences Program and Department of Physics, Michigan Technological University, Houghton, MI, USA.
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Yuan Q, Xu J, Wang Y, Zhang X, Pang Y, Liu L, Bi L, Kang S, Li W. Mixing State and Fractal Dimension of Soot Particles at a Remote Site in the Southeastern Tibetan Plateau. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8227-8234. [PMID: 31251592 DOI: 10.1021/acs.est.9b01917] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The mixing state and fractal dimension (Df) of soot particles are two major factors affecting their absorption capacity and their climate effects. Here we investigated these factors of soot particles found in a typical valley of the southeastern Tibetan Plateau where wood burning in local villages was one major source of soot particles. Our motivation revealed Df and the aging property of soot particles in remote air and discussed their regional climatic implications. We found that 64% of total analyzed particles by number were soot-bearing particles and most of them aged with sulfate or organic coating. The Df sequence is bare-like soot (1.75 ± 0.08) < partly coated soot (1.82 ± 0.05) < embedded soot (1.88 ± 0.05). The aging process enlarged the overall size of the soot-bearing particles and increased the compactness of soot. Soot aging critically depended on high relative humidity (RH) during nighttime. Besides emission sources and coating processes, the coating aerosol phase under different RHs is another important factor affecting the soot Df.
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Affiliation(s)
- Qi Yuan
- Department of Atmospheric Sciences, School of Earth Sciences , Zhejiang University , Hangzhou 310027 , Zhejiang , China
| | - Jianzhong Xu
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources , Chinese Academy of Sciences (CAS) , Lanzhou 730000 , Gansu , China
| | - Yuanyuan Wang
- Department of Atmospheric Sciences, School of Earth Sciences , Zhejiang University , Hangzhou 310027 , Zhejiang , China
| | - Xinghua Zhang
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources , Chinese Academy of Sciences (CAS) , Lanzhou 730000 , Gansu , China
| | - Yuner Pang
- Department of Atmospheric Sciences, School of Earth Sciences , Zhejiang University , Hangzhou 310027 , Zhejiang , China
| | - Lei Liu
- Department of Atmospheric Sciences, School of Earth Sciences , Zhejiang University , Hangzhou 310027 , Zhejiang , China
| | - Lei Bi
- Department of Atmospheric Sciences, School of Earth Sciences , Zhejiang University , Hangzhou 310027 , Zhejiang , China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources , Chinese Academy of Sciences (CAS) , Lanzhou 730000 , Gansu , China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences , Beijing 100101 , China
| | - Weijun Li
- Department of Atmospheric Sciences, School of Earth Sciences , Zhejiang University , Hangzhou 310027 , Zhejiang , China
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Chen C, Enekwizu OY, Fan X, Dobrzanski CD, Ivanova EV, Ma Y, Gor GY, Khalizov AF. Single Parameter for Predicting the Morphology of Atmospheric Black Carbon. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:14169-14179. [PMID: 30462499 DOI: 10.1021/acs.est.8b04201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Black carbon (BC) from fuel combustion is an effective light absorber that contributes significantly to direct climate forcing. The forcing is altered when BC combines with other substances, which modify its mixing state and morphology, making the evaluation of its atmospheric lifetime and climate impact a challenge. To elucidate the associated mechanisms, we exposed BC aerosol to supersaturated vapors of different chemicals to form thin coatings and measured the coating mass required to induce the restructuring of BC aggregates. We found that studied chemicals fall into two distinct groups based on a single dimensionless parameter, χ, which depends on the diameter of BC monomer spheres and the coating material properties, including vapor supersaturation, molar volume, and surface tension. We show that when χ is small (low-volatility chemicals), the highly supersaturated vapor condenses uniformly over aggregates, including convex monomers and concave junctions in between monomers, but when χ is large (intermediate-volatility chemicals), junctions become preferred. The aggregates undergo prompt restructuring when condensation in the junctions dominates over condensation on monomer spheres. For a given monomer diameter, the coating distribution is mostly controlled by vapor supersaturation. The χ factor can be incorporated straightforwardly into atmospheric models to improve simulations of BC aging.
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Affiliation(s)
- Chao Chen
- College of Resources and Environment , Chengdu University of Information Technology , Chengdu 610225 , China
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control , Nanjing University of Information Science & Technology , Nanjing 210044 , China
- Department of Chemistry and Environmental Science , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
| | - Ogochukwu Y Enekwizu
- Department of Chemical and Materials Engineering , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
| | - Xiaolong Fan
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control , Nanjing University of Information Science & Technology , Nanjing 210044 , China
- Department of Chemistry and Environmental Science , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
| | - Christopher D Dobrzanski
- Department of Chemical and Materials Engineering , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
| | - Ella V Ivanova
- Saint-Petersburg State University , 7-9 Universitetskaya nab. , Saint-Petersburg , Russian Federation 199034
| | - Yan Ma
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control , Nanjing University of Information Science & Technology , Nanjing 210044 , China
| | - Gennady Y Gor
- Department of Chemical and Materials Engineering , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
| | - Alexei F Khalizov
- Department of Chemistry and Environmental Science , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
- Department of Chemical and Materials Engineering , New Jersey Institute of Technology , Newark , New Jersey 07102 , United States
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Lin L, Chen G, Yan J, Tang R, Yuan X, Yin Z, Zhang R. A factor analysis of landscape metrics of particles deposited on leaf surface. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:28391-28402. [PMID: 30083903 DOI: 10.1007/s11356-018-2804-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 07/19/2018] [Indexed: 06/08/2023]
Abstract
Particulate matter in the airborne environment is one of the top environmental concerns, as well as reasons of deaths and diverse diseases. Urban green infrastructure can improve the air quality by mitigating particulate matters from airborne environment and provide high spatial monitoring of particles by means of leaf particles as indicators. Three common species in Beijing (ailanthus, ash, and willow) were chosen to represent three different leaf characteristics. Then, we analyzed the correlation relationship of the particle metrics at landscape, class, and patch levels and implemented the principal components analysis and factor analysis. Firstly, at landscape level, metrics are mostly correlated with each other and the correlation relationship of metrics of ailanthus and willow were stronger than that of ash, which has coarse-texture leaves without hair. At class level, most of the metrics were correlated and the correlation relationship of metrics of ailanthus, whose leaves have microgrooves without hair, was weaker than that of ash and willow. At patch level, judging from proximity, the distance between particles from the same range was smaller for particles with complicated shape. Secondly, particles from four ranges were analyzed separately. The shape complexity of particles decreased and increased as the area increased respectively for PM1 (diameter ≤ 1 μm) and large particles (diameter ≥ 10 μm). Two principle components were identified for landscape and class levels respectively. These results will be useful for the in-depth understanding of the particles deposited on the leaf surface.
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Affiliation(s)
- Lin Lin
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Guojian Chen
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jingli Yan
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- Department of Botany and Plant Sciences, University of California-Riverside, 900 University Ave, Riverside, CA, 92521, USA
| | - Rongli Tang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- Chongqing Academy of Agricultural Sciences, Chongqing, China
| | - Xiu Yuan
- Institutes of Science and Development, Chinese Academy of Sciences, Beijing, China
| | - Zhe Yin
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Rui Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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14
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Evolution of Multispectral Aerosol Absorption Properties in a Biogenically-Influenced Urban Environment during the CARES Campaign. ATMOSPHERE 2017. [DOI: 10.3390/atmos8110217] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Bharti SK, Kumar D, Anand S, Poonam, Barman SC, Kumar N. Characterization and morphological analysis of individual aerosol of PM 10 in urban area of Lucknow, India. Micron 2017; 103:90-98. [PMID: 29031165 DOI: 10.1016/j.micron.2017.09.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 09/01/2017] [Accepted: 09/03/2017] [Indexed: 10/18/2022]
Abstract
Airborne particulate matters were collected during the period of October 2015 to September 2016 in Lucknow at different sampling sites. The annual mean concentration of particulate matter was found to be relatively higher than the limits prescribed by National ambient air quality standards (NAAQS), United State Environmental Protection Agency (USEPA) and World Health Organization (WHO). Particulate matters were studied for morphological analysis, elemental composition and functional group variability with the help of Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS) followed by Fourier Transform Infrared spectroscopy (FTIR). Morphological characteristics viz. particle count, aspect ratio, circulatory, roundness, equivalent spherical diameter (ESD) and surface area revealed that the particles were perfectly spherical to irregular in shape. Based on the morphology and elemental composition, four clusters of a particulates namely organic particle with inorganic inclusion, soot, tar balls and aluminosilicates were found. FTIR spectra revealed the presence of sulfate, bisulfate, particulate water, silicate, ammonium, aliphatic carbon, aliphatic alcohol, carbonyl and organic nitrates.
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Affiliation(s)
- Sushil Kumar Bharti
- Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, Uttar Pradesh, India
| | - Dhananjay Kumar
- Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, Uttar Pradesh, India
| | - Sangeeta Anand
- Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, Uttar Pradesh, India
| | - Poonam
- Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, Uttar Pradesh, India
| | - Shymal Chandra Barman
- Environmental Monitoring Division, Indian Institute of Toxicology Research, Mahatma Gandhi Marg, Lucknow, 226 001, Uttar Pradesh, India
| | - Narendra Kumar
- Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, Uttar Pradesh, India.
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Effect of Thermodenuding on the Structure of Nascent Flame Soot Aggregates. ATMOSPHERE 2017. [DOI: 10.3390/atmos8090166] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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17
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18
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Monthly and Diurnal Variation of the Concentrations of Aerosol Surface Area in Fukuoka, Japan, Measured by Diffusion Charging Method. ATMOSPHERE 2017. [DOI: 10.3390/atmos8070114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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19
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Laskin A, Gilles MK, Knopf DA, Wang B, China S. Progress in the Analysis of Complex Atmospheric Particles. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2016; 9:117-43. [PMID: 27306308 DOI: 10.1146/annurev-anchem-071015-041521] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This article presents an overview of recent advances in field and laboratory studies of atmospheric particles formed in processes of environmental air-surface interactions. The overarching goal of these studies is to advance predictive understanding of atmospheric particle composition, particle chemistry during aging, and their environmental impacts. The diversity between chemical constituents and lateral heterogeneity within individual particles adds to the chemical complexity of particles and their surfaces. Once emitted, particles undergo transformation via atmospheric aging processes that further modify their complex composition. We highlight a range of modern analytical approaches that enable multimodal chemical characterization of particles with both molecular and lateral specificity. When combined, these approaches provide a comprehensive arsenal of tools for understanding the nature of particles at air-surface interactions and their reactivity and transformations with atmospheric aging. We discuss applications of these novel approaches in recent studies and highlight additional research areas to explore the environmental effects of air-surface interactions.
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Affiliation(s)
- Alexander Laskin
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354;
| | - Mary K Gilles
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Daniel A Knopf
- Institute for Terrestrial and Planetary Atmospheres, School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794
| | - Bingbing Wang
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354;
| | - Swarup China
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354;
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Factors Controlling the Variation of Aerosol Surface Area Concentrations Measured by a Diffusion Charger in Fukuoka, Japan. ATMOSPHERE 2016. [DOI: 10.3390/atmos7030033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Zhang R, Kook S. Influence of fuel injection timing and pressure on in-flame soot particles in an automotive-size diesel engine. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8243-8250. [PMID: 24933154 DOI: 10.1021/es500661w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The current understanding of soot particle morphology in diesel engines and their dependency on the fuel injection timing and pressure is limited to those sampled from the exhaust. In this study, a thermophoretic sampling and subsequent transmission electron microscope imaging were applied to the in-flame soot particles inside the cylinder of a working diesel engine for various fuel injection timings and pressures. The results show that the number count of soot particles per image decreases by more than 80% when the injection timing is retarded from -12 to -2 crank angle degrees after the top dead center. The late injection also results in over 90% reduction of the projection area of soot particles on the TEM image and the size of soot aggregates also become smaller. The primary particle size, however, is found to be insensitive to the variations in fuel injection timing. For injection pressure variations, both the size of primary particles and soot aggregates are found to decrease with increasing injection pressure, demonstrating the benefits of high injection velocity and momentum. Detailed analysis shows that the number count of soot particles per image increases with increasing injection pressure up to 130 MPa, primarily due to the increased small particle aggregates that are less than 40 nm in the radius of gyration. The fractal dimension shows an overall decrease with the increasing injection pressure. However, there is a case that the fractal dimension shows an unexpected increase between 100 and 130 MPa injection pressure. It is because the small aggregates with more compact and agglomerated structures outnumber the large aggregates with more stretched chain-like structures.
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Affiliation(s)
- Renlin Zhang
- School of Mechanical and Manufacturing Engineering, the University of New South Wales , Sydney, New South Wales 2052, Australia
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