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Mukherjee A, Hartikainen A, Joutsensaari J, Basnet S, Mesceriakovas A, Ihalainen M, Yli-Pirilä P, Leskinen J, Somero M, Louhisalmi J, Fang Z, Kalberer M, Rudich Y, Tissari J, Czech H, Zimmermann R, Sippula O. Black carbon and particle lung-deposited surface area in residential wood combustion emissions: Effects of an electrostatic precipitator and photochemical aging. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 952:175840. [PMID: 39214360 DOI: 10.1016/j.scitotenv.2024.175840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 08/14/2024] [Accepted: 08/26/2024] [Indexed: 09/04/2024]
Abstract
Residential wood combustion (RWC) remains a significant global source of particulate matter (PM) emissions with adverse impacts on regional air quality, climate, and human health. The lung-deposited surface area (LDSA) and equivalent black carbon (eBC) concentrations have emerged as important metrics to assess particulate pollution. In this study we estimated combustion phase-dependent emission factors of LDSA for alveolar, tracheobronchial, and head-airway regions of human lungs and explored the relationships between eBC and LDSA in fresh and photochemically aged RWC emissions. Photochemical aging was simulated in an oxidative flow reactor at OH• exposures equivalent to 1.4 or 3.4 days in the atmosphere. Further, the efficiency of a small-scale electrostatic precipitator (ESP) for reducing LDSA and eBC from the wood stove was determined. For fresh emission eBC correlated extremely well with LDSA, but the correlation decreased after aging. Soot-dominated flaming phase showed the highest eBC dependency of LDSA whereas for ignition and char burning phases non-BC particles contributed strongly the LDSA. Deposition to the alveolar region contributed around 60 % of the total lung-deposition. The ESP was found as an effective method to mitigate particulate mass, LDSA, as well as eBC emissions from wood stoves, as they were reduced on average by 72%, 71%, and 69%, respectively. The reduction efficiencies, however, consistently dropped over the span of an experiment, especially for eBC. Further, the ESP was found to increase the sub-30 nm ultrafine particle number emissions, with implications for LDSA. The results of this study can be used for assessing the contribution of RWC to LDSA concentrations in ambient air.
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Affiliation(s)
- A Mukherjee
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland.
| | - A Hartikainen
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland.
| | - J Joutsensaari
- Department of Technical Physics, University of Eastern Finland, Kuopio 70210, Finland
| | - S Basnet
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - A Mesceriakovas
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - M Ihalainen
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - P Yli-Pirilä
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - J Leskinen
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - M Somero
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - J Louhisalmi
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - Z Fang
- Department of Earth and Planetary Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - M Kalberer
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | - Y Rudich
- Department of Earth and Planetary Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - J Tissari
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland
| | - H Czech
- Group of Comprehensive Molecular Analytics, Helmholtz Zentrum München, Neuherberg 85764, Germany; Department of Technical and Analytical Chemistry, University of Rostock, Rostock 18056, Germany
| | - R Zimmermann
- Group of Comprehensive Molecular Analytics, Helmholtz Zentrum München, Neuherberg 85764, Germany; Department of Technical and Analytical Chemistry, University of Rostock, Rostock 18056, Germany
| | - O Sippula
- Department of Environmental and Biological Science, University of Eastern Finland, Kuopio 70210, Finland; Department of Chemistry, University of Eastern Finland, Joensuu 80101, Finland.
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Zhang Z, Cheng Y, Liang L, Liu J. The Measurement of Atmospheric Black Carbon: A Review. TOXICS 2023; 11:975. [PMID: 38133376 PMCID: PMC10748019 DOI: 10.3390/toxics11120975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/16/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
Black Carbon (BC), the second-largest contributor to global warming, has detrimental effects on human health and the environment. However, the accurate quantification of BC poses a significant challenge, impeding the comprehensive assessment of its impacts. Therefore, this paper aims to critically review three quantitative methods for measuring BC: Thermal Optical Analysis (TOA), the Optical Method, and Laser-Induced Incandescence (LII). The determination principles, available commercial instruments, sources of deviation, and correction approaches associated with these techniques are systematically discussed. By synthesizing and comparing the quantitative results reported in previous studies, this paper aims to elucidate the underlying relationships and fundamental disparities among Elemental Carbon (EC), Equivalent Black Carbon (eBC), and Refractory Black Carbon (rBC). Finally, based on the current advancements in BC quantification, recommendations are proposed to guide future research directions.
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Affiliation(s)
- Zhiqing Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; (Z.Z.); (Y.C.)
| | - Yuan Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; (Z.Z.); (Y.C.)
| | - Linlin Liang
- State Key Laboratory of Severe Weather & Key Laboratory for Atmospheric Chemistry, Chinese Academy of Meteorological Sciences, Beijing 100081, China
| | - Jiumeng Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; (Z.Z.); (Y.C.)
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3
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Optical Characterization of Fresh and Photochemically Aged Aerosols Emitted from Laboratory Siberian Peat Burning. ATMOSPHERE 2022. [DOI: 10.3390/atmos13030386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Carbonaceous aerosols emitted from biomass burning influence radiative forcing and climate change. Of particular interest are emissions from high-latitude peat burning because amplified climate change makes the large carbon mass stored in these peatlands more susceptible to wildfires and their emission can affect cryosphere albedo and air quality after undergoing transport. We combusted Siberian peat in a laboratory biomass-burning facility and characterized the optical properties of freshly emitted combustion aerosols and those photochemically aged in an oxidation flow reactor (OFR) with a three-wavelength photoacoustic instrument. Total particle count increased with aging by a factor of 6 to 11 while the total particle volume either changed little (<8%) for 19 and 44 days of equivalent aging and increased by 88% for 61 days of equivalent aging. The aerosol single-scattering albedo (SSA) of both fresh and aged aerosol increased with the increasing wavelength. The largest changes in SSA due to OFR aging were observed at the shortest of the three wavelengths (i.e., at 405 nm) where SSA increased by less than ~2.4% for 19 and 44 days of aging. These changes were due to a decrease in the absorption coefficients by ~45%, with the effect on SSA somewhat reduced by a concurrent decrease in the scattering coefficients by 20 to 25%. For 61 days of aging, we observed very little change in SSA, namely an increase of 0.31% that was caused a ~56% increase in the absorption coefficients that was more than balanced by a somewhat larger (~71%) increase in the scattering coefficients. These large increases in the absorption and scattering coefficients for aging at 7 V are at least qualitatively consistent with the large increase in the particle volume (~88%). Overall, aging shifted the absorption toward longer wavelengths and decreased the absorption Ångström exponents, which ranged from ~5 to 9. Complex refractive index retrieval yielded real and imaginary parts that increased and decreased, respectively, with the increasing wavelength. The 405 nm real parts first increased and then decreased and imaginary parts decreased during aging, with little change at other wavelengths.
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He JJ, Hu QX, Jiang MN, Huang QX. Nanostructure and reactivity of soot particles from open burning of household solid waste. CHEMOSPHERE 2021; 269:129395. [PMID: 33385669 DOI: 10.1016/j.chemosphere.2020.129395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/15/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
The main purpose of this work was to quantify and characterize chemically and morphologically the emission of soot particles from the open burning of several common solid waste including paperboard, wood, peel, chemical fiber, polyethylene (PE) and polyvinyl chloride (PVC). The experiment was conducted in a laboratory-scale open-burning combustor with a dilution sampling system to obtain soot particles. The thermogravimetric profiles (TGA) showed an increasing order of oxidation reactivity: PE > PVC > fiber > paper ≈ peel > wood. High resolution transmission electron microscopy (HRTEM) images revealed more detailed information about the morphology and the particle size of soot aggregates. Subsequent quantification of nanostructure by fringe analysis showed that plastics generated soot particles with the looser carbon layers with higher tortuosity compared to the three kind of biomass. Raman spectroscopy further confirms the observed differences. In addition, wood soot exhibited the highest content of C-OH group (17.5%) among the six samples (X-Ray photoelectron spectroscopy, XPS), whereas PE and PVC soot exhibited the highest absorption peaks of aliphatic C-H groups (Fourier transform infrared spectroscopy, FTIR). Comparative analysis revealed that the interlayer distance was more important on the evaluation of reactivity than soot morphologies. The present work concluded that the physiochemical characteristics of soot particles releasing during open burning are strongly depending on waste composition and provided new data for the understanding of soot emissions from open burning.
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Affiliation(s)
- Jun-Jie He
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Qin-Xuan Hu
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Ming-Nan Jiang
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Qun-Xing Huang
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China; Alibaba-Zhejiang University Joint Research Institute of Frontier Technologies, China.
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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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6
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Criteria-Based Identification of Important Fuels for Wildland Fire Emission Research. ATMOSPHERE 2020. [DOI: 10.3390/atmos11060640] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Studies of the emissions from wildland fires are important for understanding the role of these events in the production, transport, and fate of emitted gases and particulate matter, and, consequently, their impact on atmospheric and ecological processes, and on human health and wellbeing. Wildland fire emission research provides the quantitative information needed for the understanding and management of wildland fire emissions impacts based on human needs. Recent work to characterize emissions from specific fuel types, or those from specific areas, has implicitly been driven by the recognition of the importance of those fuel types in the context of wildland fire science; however, the importance of specific fuels in driving investigations of biomass-burning emissions has not been made explicit thus far. Here, we make a first attempt to discuss the development and application of criteria to answer the question, “What are the most important fuels for biomass-burning emissions investigations to inform wildland fire science and management?” Four criteria for fuel selection are proposed: “(1) total emissions, (2) impacts, (3) availability and uncertainty, and (4) potential for future importance.” Attempting to develop and apply these criteria, we propose a list of several such fuels, based on prior investigations and the body of wildland-fire emission research.
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Farra YM, Eden MJ, Coleman JR, Kulkarni P, Ferris CF, Oakes JM, Bellini C. Acute neuroradiological, behavioral, and physiological effects of nose-only exposure to vaporized cannabis in C57BL/6 mice. Inhal Toxicol 2020; 32:200-217. [PMID: 32475185 DOI: 10.1080/08958378.2020.1767237] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Objective: The rapid increase of cannabis consumption reinforces the need to elucidate the health hazards of this practice. The presence of fine particulate matter in cannabis smoke and vapor poses a major concern, as it may contribute to cardiopulmonary disease. To facilitate the assessment of risks associated with cannabis inhalation, we developed and characterized a method for exposing mice to cannabis in a way that mimics the delivery of the drug to the airways of smokers. Materials and Methods: Cannabis (10.3% THC, 0.05% CBD) was vaporized to generate aerosols with a reproducible particle profile. Aerosols were acutely delivered to male, adult C57BL/6 mice via a nose-only exposure system. Serum THC levels were measured for increasing cannabis doses. Blood pressure and heart rate were recorded at baseline and following exposure. Behavioral response to cannabis inhalation in the open field was documented. Awake neurological activity upon cannabis exposure was monitored using BOLD fMRI.Results and Discussion: Cannabis aerosols contained particles with count median diameter of 243 ± 39 nm and geometric standard deviation of 1.56 ± 0.06. Blood serum THC levels increased linearly with aerosolized mass and peaked at 136 ± 5 ng/mL. Cannabis inhalation decreased heart rate and blood pressure but promoted anxiety-like behavior. Observed differences in BOLD activation volumes linked cannabis to increased awareness to sensory stimuli and reduced behavioral arousal.Conclusions: Quantified physiological, behavioral, and neurological responses served as validation for our mouse model of cannabis inhalation. Animal models of aerosol exposure will be instrumental for uncovering the health outcomes of chronic cannabis use.
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Affiliation(s)
- Yasmeen M Farra
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Matthew J Eden
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - James R Coleman
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA, USA
| | - Praveen Kulkarni
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA, USA
| | - Craig F Ferris
- Department of Psychology, Center for Translational NeuroImaging, Northeastern University, Boston, MA, USA
| | - Jessica M Oakes
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Chiara Bellini
- Department of Bioengineering, Northeastern University, Boston, MA, USA
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8
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Can the Aerosol Absorption Ångström Exponent Represent Aerosol Color in the Atmosphere: A Numerical Study. ATMOSPHERE 2020. [DOI: 10.3390/atmos11020187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The aerosol absorption Ångström exponent (AAE) is widely used to indicate aerosol absorption spectrum variations and is an important parameter for characterizing aerosol optical absorption properties. This study discusses the relationship between aerosol AAEs and their colors numerically. By combining light scattering simulations, a two-stream radiative transfer model, and an RGB (Red, Green, and Blue) color model, aerosol colors that can be sensed by human eyes are numerically generated with both the solar spectrum and human eye response taken into account. Our results indicate that the responses of human eyes to visible light might be more significant than the incident spectrum in the simulation of aerosol color in the atmosphere. Using the improved numerical simulation algorithm, we obtain the color change of absorption aerosols with different AAEs. When the AAE value is small, the color of the aerosol is generally black and gray. When the AAE value increases to approximately 2 and the difference between the light transmittances at wavelengths of 400 nm and 730 nm is greater than 0.2, the aerosol will appear brown or yellow.
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Mehadi A, Moosmüller H, Campbell DE, Ham W, Schweizer D, Tarnay L, Hunter J. Laboratory and field evaluation of real-time and near real-time PM 2.5 smoke monitors. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2020; 70:158-179. [PMID: 31403397 DOI: 10.1080/10962247.2019.1654036] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Increases in large wildfire frequency and intensity and a longer fire season in the western United States are resulting in a significant increase in air pollution, including concentrations of PM2.5 (particulate matter <2.5 µm in aerodynamic diameter) that pose significant health risks to nearby communities. During wildfires, government agencies monitor PM2.5 mass concentrations providing information and actions needed to protect affected communities; this requires continuously measuring instruments. This study assessed the performance of seven candidate instruments: (1) Met One Environmental beta attenuation monitor (EBAM), (2) Met One ES model 642 (ES642), (3) Grimm Environmental Dust Monitor 164 (EDM), (4) Thermo ADR 1500 (ADR), (5) TSI DRX model 8543 (DRX), (6) Dylos 1700 (Dylos), and (7) Purple Air II (PA-II) in comparison with a BAM 1020 (BAM) reference instrument. With the exception of the EBAM, all candidates use light scattering to determine PM2.5 mass concentrations. Our comparison study included environmental chamber and field components, with two of each candidate instrument operating next to the reference instrument. The chamber component involved 6 days of comparisons for biomass combustion emissions. The field component involved operating all instruments in an air monitoring station for 39.5 days with hourly average relative humidity (RH) ranging from 19% to 98%. Goals were to assess instrument precision and accuracy and effects of RH, elemental carbon (EC), and organic carbon (OC) concentrations. All replicate candidate instruments showed high hourly correlations (R2 ≥ 0.80) and higher daily average correlations (R2 ≥ 0.90), where all instruments correlated well (R2 ≥ 0.80) with the reference. The DRX and Purple Air overestimated PM2.5 mass concentrations by a factor of ~two. Differences between candidates and reference were more pronounced at higher PM2.5 concentrations. All optical instruments were affected by high RH and by the EC/OC ratio. Equations to convert candidate instruments data to FEM BAM type data are provided to enhance the usability of data from candidate instruments.Implications: This study tested the performance of seven candidate PM2.5 mass concentration measuring instruments in two settings - environmental chamber and field. The instruments were tested to determine their suitability for use during biomass combustion events and the effects of RH, PM mass concentrations, and concentrations of EC and OC on their performance. The accuracy and precision of each monitor and effect of RH, PM concentration, EC and OC concentrations are varied. The data show that most of these candidate instruments are suitable for measuring PM2.5 concentration during biomass combustions with a proper correction factor for each instrument type.
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Affiliation(s)
- Ahmed Mehadi
- Monitoring and Laboratory Division, California Air Resources Board, Sacramento, CA, USA
| | - Hans Moosmüller
- Desert Research Institute, Nevada System of Higher Education, Reno, NV, USA
| | - David E Campbell
- Desert Research Institute, Nevada System of Higher Education, Reno, NV, USA
| | - Walter Ham
- Monitoring and Laboratory Division, California Air Resources Board, Sacramento, CA, USA
| | - Donald Schweizer
- U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, Bishop, CA, USA
- Health Sciences Research Institute, University of California, Merced, CA, USA
| | - Leland Tarnay
- U.S. Department of Agriculture, Forest Service, Pacific Southwest Region Remote Sensing Lab, McClellan, CA, USA
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10
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Refractive Indices of Biomass Burning Aerosols Obtained from African Biomass Fuels Using RDG Approximation. ATMOSPHERE 2020. [DOI: 10.3390/atmos11010062] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Biomass burning (BB) aerosols contribute to climate forcing, but much is still unknown about the extent of this forcing, owing partially to the high level of uncertainty regarding BB aerosol optical properties. A key optical parameter is the refractive index (RI), which influences the absorbing and scattering properties of aerosols. This quantity is not measured directly, but it is obtained by fitting the measured scattering cross section and extinction cross section to a theoretical model using the RI as a fitting parameter. We used the Rayleigh–Debye–Gans (RDG) approximation to retrieve the complex RI of freshly emitted BB aerosol from two fuels (eucalyptus and olive) from Africa in the spectral range of 500–580 nm. Experimental measurements were carried out using cavity ring-down spectroscopy to measure extinction over the range of wavelengths of 500–580 nm and nephelometry to measure scattering at three wavelengths of 450, 550, and 700 nm for size-selected BB aerosol particles. The fuels were combusted in a tube furnace at a temperature of 800 °C, which is representative of the flaming stage of burning. Filter samples were collected and imaged using tunneling electron microscopy to obtain information on the morphology and size of the particles, which was used in the RDG calculations. The mean radii of the monomers were 27.8 and 31.5 nm for the eucalyptus and the olive fuels, respectively. The components of the retrieved complex RI were in the range of 1.31 ≤ n ≤ 1.56 and 0.045 ≤ k ≤ 0.468. The real and complex parts of the RI increase with increasing particle mobility diameter. The real part of the RI is lower, and the imaginary part is higher than what was recommended in literature for black carbon generated by propane or field measurements from fires of mixed wood samples. Fuel dependent results from controlled laboratory experiments can be used in climate modeling efforts and to constrain field measurements from biomass burning.
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11
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Characteristics of Spherical Organic Particles Emitted from Fixed-Bed Residential Coal Combustion. ATMOSPHERE 2019. [DOI: 10.3390/atmos10080441] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Residential coal combustion is one of the most significant sources of carbonaceous aerosols in the Highveld region of South Africa, significantly affecting the local and regional climate. This study investigated single coal-burning particles emitted when using different fire-ignition techniques (top-lit up-draft versus bottom-lit up-draft) and air ventilation rates (defined by the number of air holes above and below the fire grate) in selected informal braziers. Aerosol samples were collected on nucleopore filters at the Sustainable Energy Technology and Research Centre Laboratory, University of Johannesburg. The individual particles (~700) were investigated using a scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (EDX). Two distinct forms of spherical organic particles (SOPs) were identified, one less oxidized than the other. The particles were further classified into electronically dark and bright. The EDX analysis showed that 70% of the dark spherical organic particles had higher (~60%) relative oxygen content than in the bright SOPs. The morphology of spherical organic particles were quantified and classified into four categories: ~50% were bare single particles; ~35% particles were aggregated and formed diffusion accretion chains; 10% had inclusions, and 5% were deformed due to impaction on filter material during sampling. This study concludes that there are two distinct kinds of coal burning spherical organic particles and that dark SOPs are less volatile than bright SOPs. The authors also show that these spherical organic particles are similar in nature and characteristics to tar balls observed in biomass combustion and that they have the potential to absorb sunlight thereby affecting the earth’s radiative budget and climate. This study provides insights into the mixing states, morphology, and possible formation mechanisms of these organic particles from residential coal combustion in informal stoves.
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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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Contribution of Fine Particles to Air Emission at Different Phases of Biomass Burning. ATMOSPHERE 2019. [DOI: 10.3390/atmos10050278] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Particle size distribution in biomass smoke was observed for different burning phases, including flaming and smouldering, during the combustion of nine common Australian vegetation representatives. Smoke particles generated during the smouldering phase of combustions were found to be coarser as compared to flaming aerosols for all hard species. In contrast, for leafy species, this trend was inversed. In addition, the combustion process was investigated over the entire duration of burning by acquiring data with one second time resolution for all nine species. Particles were separately characterised in two categories: fine particles with dominating diffusion properties measurable with diffusion-based instruments (Dp < 200 nm), and coarse particles with dominating inertia (Dp > 200 nm). It was found that fine particles contribute to more than 90 percent of the total fresh smoke particles for all investigated species.
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14
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Trubetskaya A, Kling J, Ershag O, Attard TM, Schröder E. Removal of phenol and chlorine from wastewater using steam activated biomass soot and tire carbon black. JOURNAL OF HAZARDOUS MATERIALS 2019; 365:846-856. [PMID: 30481735 DOI: 10.1016/j.jhazmat.2018.09.061] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 08/28/2018] [Accepted: 09/23/2018] [Indexed: 05/13/2023]
Abstract
This study aims to demonstrate a novel method for removing toxic chemicals using soot produced from wood and herbaceous biomass pyrolyzed in a drop tube reactor and tire pyrolytic carbon black. The influence of ash content, nanostructure, particle size, and porosity on the filter efficiency of steam activated carbon materials was studied. It has been shown for the first time that steam activated soot and carbon black can remove phenol and chloride with filter efficiencies as high as 95%. The correlation of filter efficiency to material properties showed that the presence of alkali and steam activation time were the key parameters affecting filter efficiencies. This study shows that steam activated biomass soot and tire carbon black are promising alternatives for the cleaning of wastewater.
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Affiliation(s)
- Anna Trubetskaya
- School of Engineering and Ryan Institute, National University of Ireland, H91TK33 Galway, Ireland.
| | - Jens Kling
- Center for Electron Nanoscopy, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Olov Ershag
- Scandinavian Enviro Systems AB, Regnbågsgatan 8C, 41755 Göteborg, Sweden
| | - Thomas M Attard
- Green Chemistry Centre of Excellence, Department of Chemistry, The University of York, Heslington, York YO10 5DD, UK
| | - Elisabeth Schröder
- IKET, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
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15
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Sahu RK, Pervez S, Chow JC, Watson JG, Tiwari S, Panicker AS, Chakrabarty RK, Pervez YF. Temporal and spatial variations of PM 2.5 organic and elemental carbon in Central India. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2018; 40:2205-2222. [PMID: 29603086 DOI: 10.1007/s10653-018-0093-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 03/20/2018] [Indexed: 06/08/2023]
Abstract
This study describes spatiotemporal patterns from October 2015 to September 2016 for PM2.5 mass and carbon measurements in rural (Kosmarra), urban (Raipur), and industrial (Bhilai) environments, in Chhattisgarh, Central India. Twenty-four-hour samples were acquired once every other week at the rural and industrial sites. Twelve-hour daytime and nighttime samples were acquired either a once a week or once every other week at the urban site. Each site was equipped with two portable, battery-powered, miniVol air samplers with PM2.5 inlets. Annual average PM2.5 mass concentrations were 71.8 ± 27 µg m-3 at the rural site, 133 ± 51 µg m-3 at the urban site, and 244.5 ± 63.3 µg m-3 at the industrial site, ~ 2-6 times higher than the Indian Annual National Ambient Air Quality Standard of 40 µg m-3. Average monthly nighttime PM2.5 and carbon concentrations at the urban site were consistently higher than those of daytime from November 2015 to April 2016, when temperatures were low. Annual average total carbon (TC = OC + EC) at the urban (46.8 ± 23.8 µg m-3) and industrial (98.0 ± 17.2 µg m-3) sites also exceeded the Indian PM2.5 NAAQS. TC accounted for 30-40% of PM2.5 mass. Annual average OC ranged from 17.8 ± 6.1 µg m-3 at the rural site to 64 ± 9.4 µg m-3 at the industrial site, with EC ranging from 4.51 ± 2.2 to 34.01 ± 7.8 µg m-3. The average OC/EC ratio at the industrial site (1.88) was 18% lower than that at the urban site and 52% lower than that at the rural site. OC was attributed to 43.0% of secondary organic carbon (SOC) at the rural site, twice that estimated for the urban and industrial sites. Mortality burden estimates for PM2.5 EC are 4416 and 6196 excess deaths at the urban and industrial sites, respectively, during 2015-2016.
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Affiliation(s)
- Rakesh Kumar Sahu
- School of Studies in Chemistry, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, 492010, India
| | - Shamsh Pervez
- School of Studies in Chemistry, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, 492010, India.
| | - Judith C Chow
- Division of Atmospheric Sciences, Desert Research Institute, 2215 Raggio Parkway, Reno, NV, USA
- Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
| | - John G Watson
- Division of Atmospheric Sciences, Desert Research Institute, 2215 Raggio Parkway, Reno, NV, USA
- Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
| | - Suresh Tiwari
- Indian Institute of Tropical Meteorology Pune, New Delhi, 110 060, India
| | | | - Rajan K Chakrabarty
- Center for Aerosol Science and Engineering (CASE), Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, One Brookings Drive, St. Louis, MO, 63130, USA
| | - Yasmeen Fatima Pervez
- Department of Engineering Chemistry, CSIT, Kolihapuri, Durg, Chhattisgarh, 492010, India
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16
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Tóth Á, Hoffer A, Pósfai M, Ajtai T, Kónya Z, Blazsó M, Czégény Z, Kiss G, Bozóki Z, Gelencsér A. Chemical characterization of laboratory-generated tar ball particles. ATMOSPHERIC CHEMISTRY AND PHYSICS 2018. [DOI: 10.5194/acp-18-10407-2018] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract. The chemical properties of laboratory-generated tar ball (Lab-TB) particles
produced from dry distillate (wood tars) of three different wood species in
the laboratory were investigated by analytical techniques that had never been
used before for their characterization. The elemental compositions of
laboratory-generated tar balls (Lab-TBs) from three tree species were very
similar to one another and to those characteristic of atmospheric tar balls
(TBs) collected from the savanna fire during the SAFARI 2000 sampling
campaign. The O ∕ C and H ∕ C molar ratios of the generated Lab-TBs
were at the upper limit characteristic of soot particles. The Fourier
transform infrared spectroscopy (FT-IR) spectra of the generated Lab-TBs were
very similar to one another as well and also showed some similarity with
those of atmospheric humic-like substances (HULIS). The FT-IR measurements
indicated that Lab-TBs have a higher proportion of aromatic structure than
HULIS and the oxygen atoms of Lab-TBs are mainly found in hydroxyl and keto
functional groups. Whereas Raman activity was detected in the starting
materials of the Lab-TBs (wood tars) in the range of 1000–1800 cm−1,
the Raman spectra of TBs were dominated by two pronounced bands with
intensity maxima near 1580 (G band) and 1350 cm−1 (D band), indicating
the presence of sp2-hybridized carbon structures and disorder in them,
respectively. In the Py-GC-MS chromatograms of the Lab-TBs mostly aromatic
compounds (aromatic hydrocarbons, oxygenated aromatics and heterocyclic
aromatics) were identified in accordance with the results of Raman and FT-IR
spectroscopy. According to organic carbon ∕ elemental carbon
(OC ∕ EC) analysis using EUSAAR_2 thermal protocol, 22 % of the
total carbon content of Lab-TBs was identified as EC, contrary to
expectations based on the current understanding that negligible if any EC is
present in this sub-fraction of the brown carbon family. Our results suggest
that spherical atmospheric TBs with high C ∕ O molar ratios are closer to
BC in many of their properties than to weakly absorbing HULIS.
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17
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Castro A, Calvo AI, Blanco-Alegre C, Oduber F, Alves C, Coz E, Amato F, Querol X, Fraile R. Impact of the wood combustion in an open fireplace on the air quality of a living room: Estimation of the respirable fraction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 628-629:169-176. [PMID: 29432928 DOI: 10.1016/j.scitotenv.2018.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/25/2018] [Accepted: 02/01/2018] [Indexed: 06/08/2023]
Abstract
Presently, both in rural areas and in cities open fireplaces are still present and large quantities of wood are combusted every year. The present study aims to characterize aerosol size distribution, chemical composition and deposition in the human respiratory tract of particles emitted during the combustion of logs of oak in an open fireplace installed in the living room of a typical village house. CO2 and CO levels and aerosol size distribution have been continuously monitored and a PM10 sampler with two types of filters for chemical and microscopic analysis was also installed. The increment, between the operating periods and the indoor background, in the organic carbon and PM10 concentration due to the use of the fireplace is 15.7±0.6 (mean±standard deviation) and 58.5±6.2μgm-3, respectively. The two main polluting processes during the operation of the fireplace are the ignition with the subsequent refueling and the final cleaning of the residual ashes. In both phases mean values around 1800 particles cm-3 with CMD of 0.15μm were measured. However, while PM10 levels of 130±120μgm-3 were estimated for the ignition stage, values of 200±200μgm-3 were obtained during the final cleaning step. Assessment conducted according to ISO standard 7708:1995, demonstrated that a person who stays in a living room when an open fireplace is lit will inhale, on average, 217μgm-3 and 283μgm-3 during the ignition and the refueling stages, respectively. Subsequent refueling proved to be much less polluting. The ashes removal can also be very polluting and dangerous to health if there are hidden small incandescent embers among the ashes (estimated PM10 of 132μgm-3), reaching a CO2 level of 1940ppm and a dangerous level of CO of 132ppm.
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Affiliation(s)
- A Castro
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| | - C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - C Alves
- Centre for Environmental and Marine Studies (CESAM), Department of Environment and Planning, University of Aveiro, Aveiro 3810-193, Portugal
| | - E Coz
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, 28040, Madrid, Spain
| | - F Amato
- Institute of Environmental Assessment and Water Research, Spanish Research Council (IDAEA-CSIC), 08034 Barcelona, Spain
| | - X Querol
- Institute of Environmental Assessment and Water Research, Spanish Research Council (IDAEA-CSIC), 08034 Barcelona, Spain
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071 León, Spain
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18
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Hu T, Cao J, Zhu C, Zhao Z, Liu S, Zhang D. Morphologies and elemental compositions of local biomass burning particles at urban and glacier sites in southeastern Tibetan Plateau: Results from an expedition in 2010. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 628-629:772-781. [PMID: 29454217 DOI: 10.1016/j.scitotenv.2018.02.073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 02/07/2018] [Accepted: 02/07/2018] [Indexed: 06/08/2023]
Abstract
Many studies indicate that the atmospheric environment over the southern part of the Tibetan Plateau is influenced by aged biomass burning particles that are transported over long distances from South Asia. However, our knowledge of the particles emitted locally (within the plateau region) is poor. We collected aerosol particles at four urban sites and one remote glacier site during a scientific expedition to the southeastern Tibetan Plateau in spring 2010. Weather and backward trajectory analyses indicated that the particles we collected were more likely dominated by particles emitted within the plateau. The particles were examined using an electron microscope and identified according to their sizes, shapes and elemental compositions. At three urban sites where the anthropogenic particles were produced mainly by the burning of firewood, soot aggregates were in the majority and made up >40% of the particles by number. At Lhasa, the largest city on the Tibetan Plateau, tar balls and mineral particles were also frequently observed because of the use of coal and natural gas, in addition to biofuel. In contrast, at the glacier site, large numbers of chain-like soot aggregates (~25% by number) were noted. The morphologies of these aggregates were similar to those of freshly emitted ones at the urban sites; moreover, physically or chemically processed ageing was rarely confirmed. These limited observations suggest that the biomass burning particles age slowly in the cold, dry plateau air. Anthropogenic particles emitted locally within the elevated plateau region may thus affect the environment within glaciated areas in Tibet differently than anthropogenic particles transported from South Asia.
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Affiliation(s)
- Tafeng Hu
- Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Junji Cao
- Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
| | - Chongshu Zhu
- Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Zhuzi Zhao
- Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Suixin Liu
- Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Daizhou Zhang
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto 862-8502, Japan.
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19
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20
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Morphology, composition, and mixing state of primary particles from combustion sources - crop residue, wood, and solid waste. Sci Rep 2017; 7:5047. [PMID: 28698671 PMCID: PMC5505958 DOI: 10.1038/s41598-017-05357-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 05/26/2017] [Indexed: 11/08/2022] Open
Abstract
Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combustion released OM and S-rich particles. Interestingly, particles from hardwood (pear wood and bamboo) and softwood (cypress and pine wood) combustion were mainly soot and OM in the flaming phase, respectively. The combustion of foam boxes, rubber tires, and plastic bottles/bags in the flaming phase released large amounts of soot internally mixed with a small amount of OM, whereas the combustion of printed circuit boards and copper-core cables emitted large amounts of OM with Br-rich inclusions. In addition, the printed circuit board combustion released toxic metals containing Pb, Zn, Sn, and Sb. The results are important to document properties of primary particles from combustion sources, which can be used to trace the sources of ambient particles and to know their potential impacts in human health and radiative forcing in the air.
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21
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Montgomery JF, Rogak SN, Green SI, You Y, Bertram AK. Structural Change of Aerosol Particle Aggregates with Exposure to Elevated Relative Humidity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:12054-12061. [PMID: 26401688 DOI: 10.1021/acs.est.5b03157] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Structural changes of aggregates composed of inorganic salts exposed to relative humidity (RH) between 0 and 80% after formation at selected RH between 0 and 60% were investigated using a tandem differential mobility analyzer (TDMA) and fluorescence microscopy. The TDMA was used to measure a shift in peak mobility diameter for 100-700 nm aggregates of hygroscopic aerosol particles composed of NaCl, Na2SO4, (NH4)2SO4, and nonhygroscopic Al2O3 as the RH was increased. Aggregates of hygroscopic particles were found to shrink when exposed to RH greater than that during the aggregation process. The degree of aggregate restructuring is greater for larger aggregates and greater increases in RH. Growth factors (GF) calculated from mobility diameter measurements as low as 0.77 were seen for NaCl before deliquescence. The GF subsequently increased to 1.23 at 80% RH, indicating growth after deliquescence. Exposure to RH lower than that experienced during aggregation did not result in structural changes. Fluorescent microscopy confirmed that aggregates formed on wire surfaces undergo an irreversible change in structure when exposed to elevated RH. Analysis of 2D movement of aggregates shows a displacement of 5-13% compared to projected length of initial aggregate from a wire surface. Surface tension due to water adsorption within the aggregate structure is a potential cause of the structural changes.
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Affiliation(s)
- James F Montgomery
- Department of Mechanical Engineering, The University of British Columbia , Vancouver, Canada V6T 1Z4
| | - Steven N Rogak
- Department of Mechanical Engineering, The University of British Columbia , Vancouver, Canada V6T 1Z4
| | - Sheldon I Green
- Department of Mechanical Engineering, The University of British Columbia , Vancouver, Canada V6T 1Z4
| | - Yuan You
- Department of Chemistry, The University of British Columbia , Vancouver, Canada V6T 1Z1
| | - Allan K Bertram
- Department of Chemistry, The University of British Columbia , Vancouver, Canada V6T 1Z1
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22
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Gramsch E, Reyes E, Oyola P, Ma R, López G, Pérez P, Martínez R. Particle size distribution and its relationship to black carbon in two urban and one rural site in Santiago de Chile. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2014; 64:785-796. [PMID: 25122952 DOI: 10.1080/10962247.2014.890141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The size distribution of particles has been studied in three sites in the Metropolitan area of Santiago de Chile in the winter of 2009 and a comparison with black carbon was performed. Two sites are located near busy streets in Santiago and the other site is located in a rural area about 40 km west of Santiago with little influence from vehicles, but large influence from wood burning. The campaign lasted 1 or 2 weeks in each site. We have divided the particle size measurements into four groups (10-39 nm, 40-62 nm, 63-174 nm, and 175-700 nm) in order to compare with the carbon monitor. In the sites near the street, black carbon has a high correlation (R = 0.85) with larger particles (175-700 nm). The correlation decreased when black carbon was compared with smaller particles, having very small correlation with the smallest sizes (10-39 nm). In the rural site, black carbon also has a high correlation (R = 0.86) with larger particles (175-700 nm), but the correlation between black carbon and the finest particles (10-39 nm) decreases to near 0. These measurements are an indication that wood burning does not generate particles smaller than -50 nm. In the urban sites, particle size distribution is peaked toward smaller particles (10-39 nm) only during rush hours, but at other times, particles size distribution is peaked toward larger sizes. When solar radiation was high, evidence of secondary particle formation was seen in the rural site, but not in the urban sites. The correlation between the number of secondary particles and solar radiation was R2 = 0.46, indicating that it there may be other variables that play a role in ultrafine particle formation. Implications: A study of the size distribution of particles and black carbon concentration in two street sites and one rural site shows that in the last site the number of particles ultrafine particles (d < 40 nm) is 10 times lower but the number of larger particles is about 2 times lower. Thus, the rural site has less of the particles that are more dangerous to health. The number ofultrafine particles is mostly associated with traffic, while the number of larger particles is associated with wood burning and other sources. Wood burning does not generate particles smaller than -50 nm.
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23
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Lack DA, Moosmüller H, McMeeking GR, Chakrabarty RK, Baumgardner D. Characterizing elemental, equivalent black, and refractory black carbon aerosol particles: a review of techniques, their limitations and uncertainties. Anal Bioanal Chem 2014; 406:99-122. [PMID: 24297322 PMCID: PMC3877426 DOI: 10.1007/s00216-013-7402-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/18/2013] [Accepted: 09/25/2013] [Indexed: 12/05/2022]
Abstract
Elemental-, equivalent black- and refractory black-carbon are terms that have been defined in order to dissect the more general term, black carbon, into its component parts related to its specific chemical and optical properties and its impact on climate and health. Recent publications have attempted to clarify the meaning of these terms with respect to their environmental impact, particularly on climate. Here, we focus on the measurement aspects, reviewing the most commonly implemented techniques for the direct and indirect derivation of black carbon properties, their strengths, limitations, and uncertainties, and provide a non-exhaustive bibliography where the reader can find more detailed information. This review paper is designed as a guide for those wishing to learn about the current state of black carbon measurement instrumentation, how calibration is carried out, when one instrument may have the advantage over another, and where new techniques are needed to fill important knowledge gaps.
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Affiliation(s)
- Daniel A. Lack
- NOAA Earth System Research Laboratory, 325 Broadway, Boulder, CO 80305-3337 USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309 USA
| | | | - Gavin R. McMeeking
- Droplet Measurement Technologies, 2545 Central Avenue, Boulder, CO 80301 USA
| | | | - Darrel Baumgardner
- Droplet Measurement Technologies, 2545 Central Avenue, Boulder, CO 80301 USA
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24
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King S, Butcher AC, Rosenoern T, Coz E, Lieke K, de Leeuw G, Nilsson ED, Bilde M. Investigating primary marine aerosol properties: CCN activity of sea salt and mixed inorganic-organic particles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:10405-12. [PMID: 22809370 PMCID: PMC3462475 DOI: 10.1021/es300574u] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 07/13/2012] [Accepted: 07/18/2012] [Indexed: 05/22/2023]
Abstract
Sea spray particles ejected as a result of bubbles bursting from artificial seawater containing salt and organic matter in a stainless steel tank were sampled for size distribution, morphology, and cloud condensation nucleus (CCN) activity. Bubbles were generated either by aeration through a diffuser or by water jet impingement on the seawater surface. Three objectives were addressed in this study. First, CCN activities of NaCl and two types of artificial sea salt containing only inorganic components were measured to establish a baseline for further measurements of mixed organic-inorganic particles. Second, the effect of varying bubble residence time in the bulk seawater solution on particle size and CCN activity was investigated and was found to be insignificant for the organic compounds studied. Finally, CCN activities of particles produced from jet impingement were compared with those produced from diffuser aeration. Analyses indicate a considerable amount of organic enrichment in the jet-produced particles relative to the bulk seawater composition when sodium laurate, an organic surfactant, is present in the seawater. In this case, the production of a thick foam layer during impingement may explain the difference in activation and supports hypotheses that particle production from the two methods of generating bubbles is not equal.
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Affiliation(s)
- Stephanie
M. King
- Department
of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Andrew C. Butcher
- Department
of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Thomas Rosenoern
- Department
of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Esther Coz
- Departamento
de Medio Ambiente, CIEMAT,
E-28040 Madrid, Spain
| | - Kirsten
I. Lieke
- Department
of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Gerrit de Leeuw
- Climate
Change Unit, Finnish Meteorological Institute, FI-00560 Helsinki,
Finland
- Department
of Physics, University of Helsinki, FI-00560 Helsinki, Finland
- Department
of Air Quality and Climate, TNO Built Environment
and Geosciences, NL-3508 TA Utrecht, Netherlands
| | - E. Douglas Nilsson
- Department
of Applied Environmental Science, Stockholm
University, SE-11418 Stockholm, Sweden
| | - Merete Bilde
- Department
of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
- Phone: +45 35320329. E-mail:
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25
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Maruf Hossain AMM, Park S, Kim JS, Park K. Volatility and mixing states of ultrafine particles from biomass burning. JOURNAL OF HAZARDOUS MATERIALS 2012; 205-206:189-197. [PMID: 22244973 DOI: 10.1016/j.jhazmat.2011.12.061] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 12/16/2011] [Accepted: 12/21/2011] [Indexed: 05/31/2023]
Abstract
Fine and ultrafine carbonaceous aerosols produced from burning biomasses hold enormous importance in terms of assessing radiation balance and public health hazards. As such, volatility and mixing states of size-selected ultrafine particles (UFP) emitted from rice straw, oak, and pine burning were investigated by using volatility tandem differential mobility analyzer (VTDMA) technique in this study. Rice straw combustion produced unimodal size distributions of emitted aerosols, while bimodal size distributions from combustions of oak (hardwood) and pine (softwood) were obtained. A nearness of flue gas temperatures and a lower CO ratio of flaming combustion (FC) to smoldering combustion (SC) were characteristic differences found between softwood and hardwood. SC emitted larger mode particles in higher numbers than smaller mode particles, while the converse was true for FC. Rice straw open burning UFPs exhibited a volatilization behavior similar to that between FC and SC. In addition, internal mixing states were observed for size-selected UFPs in all biomasses for all combustion conditions, while external mixing states were only observed for rice straw combustion. Results for FC and open burning suggested there was an internal mixing of volatile organic carbon (OC) and non-volatile core (e.g., black carbon (BC)), while the SC in rice straw produced UFPs devoid of non-volatile core. Also, it was found that volatility of constituting OC in FC and SC particles was different.
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Affiliation(s)
- A M M Maruf Hossain
- School of Environmental Science & Engineering, Gwangju Institute of Science & Technology, Gwangju, Republic of Korea
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26
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Zhao S, Li Z, Zhou P. Ion chemistry and individual particle analysis of atmospheric aerosols over Mt. Bogda of eastern Tianshan Mountains, Central Asia. ENVIRONMENTAL MONITORING AND ASSESSMENT 2011; 180:409-426. [PMID: 21107902 DOI: 10.1007/s10661-010-1796-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2010] [Accepted: 11/09/2010] [Indexed: 05/30/2023]
Abstract
Aerosol samples were collected during the scientific expedition to Mt. Bogda in July-August, 2009. The major inorganic ions (Na( + ), NH⁺₄, K( + ), Mg(2 + ), Ca(2 + ), Cl( - ), SO²⁻₄, and NO⁻₃) of the aerosols were determined by ion chromatography. SO²⁻₄, NO⁻₃, and Ca(2 + ) were the dominate ions, with the mean concentrations of 0.86, 0.56, and 0.28 μg m⁻³, respectively. These mean ion concentrations were generally comparable with the background conditions in remote site of Xinjiang, while much lower than those in Ürümqi. Morphology and elemental compositions of 1,500 particles were determined by field emission scanning electron microscopy equipped with an energy dispersive X-ray spectrometer. Based on the morphology and elemental compositions, particles were classed into four major groups: soot (15.1%), fly ash (4.7%), mineral particles (78.9%), and little other matters (0.8% Fe-rich particles and 0.5% unrecognized particles). Presence of soot and fly ash particles indicated the influence of anthropogenic pollutions, while abundance mineral particles suggested that natural processes were the primary source of aerosols over this region, coinciding with the ionic analysis. Backward air mass trajectory analysis suggested that Ürümqi may contribute some anthropogenic pollution to this region, while the arid and semi-arid regions of Central Asia were the primary source.
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Affiliation(s)
- Shuhui Zhao
- State Key Laboratory of Cryospheric Sciences/Tianshan Glaciological Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
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Watson JG, Chow JC, Chen LWA, Lowenthal DH, Fujita EM, Kuhns HD, Sodeman DA, Campbell DE, Moosmüller H, Zhu D, Motallebi N. Particulate emission factors for mobile fossil fuel and biomass combustion sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:2384-2396. [PMID: 21458027 DOI: 10.1016/j.scitotenv.2011.02.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 02/23/2011] [Accepted: 02/25/2011] [Indexed: 05/30/2023]
Abstract
PM emission factors (EFs) for gasoline- and diesel-fueled vehicles and biomass combustion were measured in several recent studies. In the Gas/Diesel Split Study (GD-Split), PM(2.5) EFs for heavy-duty diesel vehicles (HDDV) ranged from 0.2 to ~2 g/mile and increased with vehicle age. EFs for HDDV estimated with the U.S. EPA MOBILE 6.2 and California Air Resources Board (ARB) EMFAC2007 models correlated well with measured values. PM(2.5) EFs measured for gasoline vehicles were ~two orders of magnitude lower than those for HDDV and did not correlate with model estimates. In the Kansas City Study, PM(2.5) EFs for gasoline-powered vehicles (e.g., passenger cars and light trucks) were generally <0.03 g/mile and were higher in winter than summer. EMFAC2007 reported higher PM(2.5) EFs than MOBILE 6.2 during winter, but not during summer, and neither model captured the variability of the measured EFs. Total PM EFs for heavy-duty diesel military vehicles ranged from 0.18±0.03 and 1.20±0.12 g/kg fuel, corresponding to 0.3 and 2 g/mile, respectively. These values are comparable to those of on-road HDDV. EFs for biomass burning measured during the Fire Laboratory at Missoula Experiment (FLAME) were compared with EFs from the ARB Emission Estimation System (EES) model. The highest PM(2.5) EFs (76.8±37.5 g/kg) were measured for wet (>50% moisture content) Ponderosa Pine needles. EFs were generally <20 g/kg when moisture content was <20%. The EES model agreed with measured EFs for fuels with low moisture content but underestimated measured EFs for fuel with moisture content >40%. Average EFs for dry chamise, rice straw, and dry grass were within a factor of three of values adopted by ARB in California's San Joaquin Valley (SJV). Discrepancies between measured and modeled emission factors suggest that there may be important uncertainties in current PM(2.5) emission inventories.
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Affiliation(s)
- John G Watson
- Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512, United States.
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Levin EJT, McMeeking GR, Carrico CM, Mack LE, Kreidenweis SM, Wold CE, Moosmüller H, Arnott WP, Hao WM, Collett JL, Malm WC. Biomass burning smoke aerosol properties measured during Fire Laboratory at Missoula Experiments (FLAME). ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013601] [Citation(s) in RCA: 133] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hand VL, Capes G, Vaughan DJ, Formenti P, Haywood JM, Coe H. Evidence of internal mixing of African dust and biomass burning particles by individual particle analysis using electron beam techniques. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd012938] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Monitoring Automotive Particulate Matter Emissions with LiDAR: A Review. REMOTE SENSING 2010. [DOI: 10.3390/rs2041077] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Cong Z, Kang S, Dong S, Liu X, Qin D. Elemental and individual particle analysis of atmospheric aerosols from high Himalayas. ENVIRONMENTAL MONITORING AND ASSESSMENT 2010; 160:323-35. [PMID: 19083111 DOI: 10.1007/s10661-008-0698-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 11/20/2008] [Indexed: 05/11/2023]
Abstract
Atmospheric aerosols were collected during the scientific expedition to Mt. Qomolangma (Everest) in May-June, 2005. The elemental concentrations of the aerosols were determined by inductively coupled plasma mass spectrometry. This yielded data for the concentration of 14 elements: Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, and Pb. The mean elemental concentrations were generally comparable with those from central Asia and the Arctic, while much higher than those from Antarctic. Size, morphology, and chemical composition of 900 individual aerosol particles were determined by scanning electron microscopy and energy-dispersive X-ray microanalysis. Based on morphology and elemental composition, the particles were clustered into eight groups: soot (8%), tar ball (3%), alumosilicates/silica (55%), calcium sulfate (16%), Ca/Mg carbonate (2%), Fe/Ti-rich particles (3%), Pb-rich particles (1%), and biological particles (12%). The sampling site, located at 6,520 m in the Himalayas, is particularly remote and located at high altitude. Nonetheless, high aerosol enrichment factors for copper, chromium, lead, nickel, vanadium, and zinc all suggest the influence of long-range transported pollution, while enrichment in calcium and the presence of alumino-silicates in individual particle analyses indicates a distinct mineral dust influence. The backward air mass trajectories showed that the northwestern part of India may contribute to the atmospheric aerosol in the central high Himalayas.
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Affiliation(s)
- Zhiyuan Cong
- Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing, 100085, China
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Petters MD, Carrico CM, Kreidenweis SM, Prenni AJ, DeMott PJ, Collett JL, Moosmüller H. Cloud condensation nucleation activity of biomass burning aerosol. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009jd012353] [Citation(s) in RCA: 185] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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McMeeking GR, Kreidenweis SM, Baker S, Carrico CM, Chow JC, Collett JL, Hao WM, Holden AS, Kirchstetter TW, Malm WC, Moosmüller H, Sullivan AP, Wold CE. Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009jd011836] [Citation(s) in RCA: 291] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chakrabarty RK, Moosmüller H, Arnott WP, Garro MA, Tian G, Slowik JG, Cross ES, Han JH, Davidovits P, Onasch TB, Worsnop DR. Low fractal dimension cluster-dilute soot aggregates from a premixed flame. PHYSICAL REVIEW LETTERS 2009; 102:235504. [PMID: 19658949 DOI: 10.1103/physrevlett.102.235504] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2008] [Indexed: 05/28/2023]
Abstract
Using a novel morphology segregation technique, we observed minority populations ( approximately 3%) of submicron-sized, cluster-dilute fractal-like aggregates, formed in the soot-formation window (fuel-to-air equivalence ratio of 2.0-3.5) of a premixed flame, to have mass fractal dimensions between 1.2 and 1.51. Our observations disagree with previous observations of a universal mass fractal dimension of approximately 1.8 for fractal-like aerosol aggregates formed in the dilute-limit via three-dimensional diffusion-limited cluster aggregation processes. A hypothesis is presented to explain this observation. Subject to verification of this hypothesis, it may be possible to control the fractal dimension and associated properties of aggregates in the cluster-dilute limit through application of a static electric field during the aggregation process.
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Affiliation(s)
- Rajan K Chakrabarty
- Desert Research Institute, Nevada System of Higher Education, Reno, NV 89512, USA.
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Li W, Shao L. Transmission electron microscopy study of aerosol particles from the brown hazes in northern China. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jd011285] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Petters MD, Parsons MT, Prenni AJ, DeMott PJ, Kreidenweis SM, Carrico CM, Sullivan AP, McMeeking GR, Levin E, Wold CE, Collett JL, Moosmüller H. Ice nuclei emissions from biomass burning. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jd011532] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lewis K, Arnott WP, Moosmüller H, Wold CE. Strong spectral variation of biomass smoke light absorption and single scattering albedo observed with a novel dual-wavelength photoacoustic instrument. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009699] [Citation(s) in RCA: 239] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Carrico CM, Petters MD, Kreidenweis SM, Collett JL, Engling G, Malm WC. Aerosol hygroscopicity and cloud droplet activation of extracts of filters from biomass burning experiments. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009274] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bein KJ, Zhao Y, Johnston MV, Wexler AS. Interactions between boreal wildfire and urban emissions. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd008910] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Obrist D, Moosmüller H, Schürmann R, Chen LWA, Kreidenweis SM. Particulate-phase and gaseous elemental mercury emissions during biomass combustion: controlling factors and correlation with particulate matter emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:721-727. [PMID: 18323093 DOI: 10.1021/es071279n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Mercury emissions from wildfires are significant natural sources of atmospheric mercury, but little is known about what controls speciation of emissions important to mercury deposition processes. The goal of this study was to quantify gaseous elemental mercury (GEM) and particulate-phase mercury (PHg) emissions from biomass combustion to identify key factors controlling the speciation. Emissions were characterized in an exhaust stack 17 m above fires using a gaseous mercury analyzer and quartz-fiber filters. Fuels included fresh and air-dried leaves, needles, and branches with different fuel moistures (9-95% of dry weight) and combustion properties (e.g., from < 10 to 90% of fire durations characterized by flaming phases). Fuel moisture was the overall driving factor defining emissions, with GEM being the dominant fraction (> or = 95%) in low moisture fuels and substantial PHg contributions--up to 50% of total mercury emissions--in fresh fuels. High PHg emissions were observed during smoldering combustion whereas flaming-dominated fires showed insignificant PHg emissions. PHg mass emissions were correlated with particulate matter (PM; r2 = 0.67), organic carbon (OC; r2 = 0.63) and sulfur (S; r2 = 0.46) mass emissions, but not with elemental carbon (EC) nor with the total mercury emissions. These data suggest that the formation of PHg involves similar processes as the formation of particulate OC, for example condensation of volatile species onto preexisting smoke particles during cooling and dilution. Based on the observed relationship between PM and OC mass concentrations and published emission inventories, we estimate global PHg emissions by wildfires of 4-5 Mg yr(-1).
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Affiliation(s)
- Daniel Obrist
- Division of Atmospheric Sciences, Desert Research Institute, Reno, Nevada, USA.
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Schichtel BA, Malm WC, Bench G, Fallon S, McDade CE, Chow JC, Watson JG. Fossil and contemporary fine particulate carbon fractions at 12 rural and urban sites in the United States. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd008605] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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