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Yuan Z, Gao S, Wang Y, Li J, Hou C, Guo L. Prediction of PM2.5 time series by seasonal trend decomposition-based dendritic neuron model. Neural Comput Appl 2023; 35:15397-15413. [PMID: 37273913 PMCID: PMC10107594 DOI: 10.1007/s00521-023-08513-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 03/21/2023] [Indexed: 06/06/2023]
Abstract
The rapid industrial development in the human society has brought about the air pollution, which seriously affects human health. PM2.5 concentration is one of the main factors causing the air pollution. To accurately predict PM2.5 microns, we propose a dendritic neuron model (DNM) trained by an improved state-of-matter heuristic algorithm (DSMS) based on STL-LOESS, namely DS-DNM. Firstly, DS-DNM adopts STL-LOESS for the data preprocessing to obtain three characteristic quantities from original data: seasonal, trend, and residual components. Then, DNM trained by DSMS predicts the residual values. Finally, three sets of feature quantities are summed to obtain the predicted values. In the performance test experiments, five real-world PM2.5 concentration data are used to test DS-DNM. On the other hand, four training algorithms and seven prediction models were selected for comparison to verify the rationality of the training algorithms and the accuracy of the prediction models, respectively. The experimental results show that DS-DNM has the more competitive performance in PM2.5 concentration prediction problem.
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Affiliation(s)
- Zijing Yuan
- Faculty of Engineering, University of Toyama, Toyama-shi, 930-8555 Japan
| | - Shangce Gao
- Faculty of Engineering, University of Toyama, Toyama-shi, 930-8555 Japan
| | - Yirui Wang
- Engineering and Computer Science, Ningbo University, Zhejiang, 315221 China
| | - Jiayi Li
- Faculty of Engineering, University of Toyama, Toyama-shi, 930-8555 Japan
| | - Chunzhi Hou
- Faculty of Engineering, University of Toyama, Toyama-shi, 930-8555 Japan
| | - Lijun Guo
- Engineering and Computer Science, Ningbo University, Zhejiang, 315221 China
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2
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Black Carbon in Bulgaria—Observed and Modelled Concentrations in Two Cities for Two Months. ATMOSPHERE 2022. [DOI: 10.3390/atmos13020213] [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
Black carbon (BC) is one of the particulate matter (PM) components that both affects human health and contributes to climate change. In this study, we present the preliminary results of the investigation of BC concentrations in PM2.5 for two Bulgarian cites—Sofia and Burgas. The parallel PM2.5 samplings were organized in October 2020 and January 2021. The Multi-Wavelength Absorption Black carbon Instrument (MABI) was used for the evaluation of light-absorbing carbon. In addition, we compared the observed BC and PM2.5 values to modelled ones and analyzed the spatial distribution over the country, using data from advanced operational chemical transport models (CTM)—the European (regional) air quality system established at the Copernicus Atmosphere Monitoring Service (CAMS). Generally, the observed BC and PM2.5 values were higher in January than in October for both cities. In October, the model underestimated the observed BC concentrations (Sofia—2.44 μg.m−3, Burgas—1.63 μg.m−3) by 17% and 51%. In January 2021, the observed monthly BC concentrations were higher (Sofia—3.62 μg.m−3, Burgas—1.75 μg.m−3), and the bias of the model was less than that in October, with an overestimation of 22% for Sofia. The relative bias for PM2.5 in October (17% for Sofia and −6% for Burgas) was less than the relative bias in January when the model underestimated PM2.5 monthly mean concentrations by 20% (Sofia) and 42% (Burgas). In addition, we also elaborate on two episodes with high observed BC concentrations in view of the meteorological conditions.
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3
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The Spatial and Temporal Distributions of Absorbing Aerosols over East Asia. REMOTE SENSING 2017. [DOI: 10.3390/rs9101050] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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4
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Zenone T, Hendriks C, Brilli F, Fransen E, Gioli B, Portillo-Estrada M, Schaap M, Ceulemans R. Interaction between isoprene and ozone fluxes in a poplar plantation and its impact on air quality at the European level. Sci Rep 2016; 6:32676. [PMID: 27615148 PMCID: PMC5018846 DOI: 10.1038/srep32676] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 08/10/2016] [Indexed: 11/09/2022] Open
Abstract
The emission of isoprene and other biogenic volatile organic compounds from vegetation plays an important role in tropospheric ozone (O3) formation. The potentially large expansion of isoprene emitting species (e.g., poplars) for bioenergy production might, therefore, impact tropospheric O3 formation. Using the eddy covariance technique we have simultaneously measured fluxes isoprene, O3 and of CO2 from a poplar (Populus) plantation grown for bioenergy production. We used the chemistry transport model LOTOS-EUROS to scale-up the isoprene emissions associated with the existing poplar plantations in Europe, and we assessed the impact of isoprene fluxes on ground level O3 concentrations. Our findings suggest that isoprene emissions from existing poplar-for-bioenergy plantations do not significantly affect the ground level of O3 concentration. Indeed the overall land in Europe covered with poplar plantations has not significantly changed over the last two decades despite policy incentives to produce bioenergy crops. The current surface area of isoprene emitting poplars-for-bioenergy remains too limited to significantly enhance O3 concentrations and thus to be considered a potential threat for air quality and human health.
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Affiliation(s)
- Terenzio Zenone
- Department of Biology, Centre of Excellence on Plant and Vegetation Ecology (PLECO), University of Antwerp, B-2610 Wilrijk, Belgium
| | - Carlijn Hendriks
- TNO, Department of Climate, Air and Sustainability, P.O. Box 80015, 3508 TA, Utrecht, the Netherlands
| | - Federico Brilli
- National Research Council, Institute of Agro-Environmental and Forest Biology (IBAF-CNR), Via Salaria Km 29,300 - 00016 Monterotondo Scalo, Roma, Italy.,National Research Council, Institute for Sustainable Plant Protection (IPSP-CNR), Via Madonna del piano 10, 50017, Sesto Fiorentino, Italy
| | - Erik Fransen
- StatUa Centre for Statistics, University of Antwerp, Prinsstraat 13, B-2000 Antwerp, Belgium
| | - Beniamio Gioli
- National Research Council, Institute of Biometeorology (IBIMET-CNR), Via G. Caproni 8, 50145, Firenze, Italy
| | - Miguel Portillo-Estrada
- Department of Biology, Centre of Excellence on Plant and Vegetation Ecology (PLECO), University of Antwerp, B-2610 Wilrijk, Belgium
| | - Martijn Schaap
- TNO, Department of Climate, Air and Sustainability, P.O. Box 80015, 3508 TA, Utrecht, the Netherlands
| | - Reinhart Ceulemans
- Department of Biology, Centre of Excellence on Plant and Vegetation Ecology (PLECO), University of Antwerp, B-2610 Wilrijk, Belgium
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Hendriks C, Kuenen J, Kranenburg R, Scholz Y, Schaap M. A shift in emission time profiles of fossil fuel combustion due to energy transitions impacts source receptor matrices for air quality. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2015; 17:510-524. [PMID: 25594282 DOI: 10.1039/c4em00444b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Effective air pollution and short-lived climate forcer mitigation strategies can only be designed when the effect of emission reductions on pollutant concentrations and health and ecosystem impacts are quantified. Within integrated assessment modeling source-receptor relationships (SRRs) based on chemistry transport modeling are used to this end. Currently, these SRRs are made using invariant emission time profiles. The LOTOS-EUROS model equipped with a source attribution module was used to test this assumption for renewable energy scenarios. Renewable energy availability and thereby fossil fuel back up are strongly dependent on meteorological conditions. We have used the spatially and temporally explicit energy model REMix to derive time profiles for backup power generation. These time profiles were used in LOTOS-EUROS to investigate the effect of emission timing on air pollutant concentrations and SRRs. It is found that the effectiveness of emission reduction in the power sector is significantly lower when accounting for the shift in the way emissions are divided over the year and the correlation of emissions with synoptic situations. The source receptor relationships also changed significantly. This effect was found for both primary and secondary pollutants. Our results indicate that emission timing deserves explicit attention when assessing the impacts of system changes on air quality and climate forcing from short lived substances.
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Affiliation(s)
- Carlijn Hendriks
- TNO, Department of Climate, Air and Sustainability, P.O. Box 80015, 3508 TA, Utrecht, The Netherlands.
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Avino P, Manigrasso M, Rosada A, Dodaro A. Measurement of organic and elemental carbon in downtown Rome and background area: physical behavior and chemical speciation. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2015; 17:300-315. [PMID: 25341186 DOI: 10.1039/c4em00471j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A significant portion of the particulate matter is the total carbonaceous fraction (or total carbon, TC), composed of two main fractions, elemental carbon (EC) and organic carbon (OC), which shows a large variety of organic compounds, e.g. aliphatic, aromatic compounds, alcohols, acids, etc. In this paper, TC, EC and OC concentrations determined in a downtown Rome urban area are discussed considering the influence of meteorological conditions on the temporal-spatial aerosol distribution. Similar measurements were performed at ENEA Casaccia, an area outside Rome, which is considered as the ome background. Since 2000, TC, EC and OC measurements have been performed by means of an Ambient Carbon Particulate Monitor equipped with a NDIR detector. The EC and OC concentrations trends are compared with benzene and CO trends, which are specific indicators of autovehicular traffic, for identifying the primary EC and OC contributions and the secondary OC fraction origin. Further, a chemical investigation is reported for investigating how the main organic (i.e., n-alkanes, n-alkanoic acids, polyaromatic hydrocarbons and nitro-polyaromatic hydrocarbons) and inorganic (i.e., metals, ions) fractions vary their levels during the investigated period in relationship to new regulations and/or technological innovations.
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Affiliation(s)
- Pasquale Avino
- DIT, INAIL settore Ricerca, via IV Novembre 144, 00187 Rome, Italy.
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7
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Cao JJ, Shen ZX, Chow JC, Watson JG, Lee SC, Tie XX, Ho KF, Wang GH, Han YM. Winter and summer PM2.5 chemical compositions in fourteen Chinese cities. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2012; 62:1214-26. [PMID: 23155868 DOI: 10.1080/10962247.2012.701193] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
UNLABELLED PM2.5 in 14 of China's large cities achieves high concentrations in both winter and summer with averages > 100 microg m(-3) being common occurrences. A grand average of 15 microg m(-3) was found for all cities, with a minimum of 27 microg m(-3) measured at Qingdao during summer and a maximum of 356 microg m(-3) at Xi 'an during winter. Both primary and secondary PM2.5 are important contributors at all of the cities and during both winter and summer. While ammonium sulfate is a large contributor during both seasons, ammonium nitrate contributions are much larger during winter. Lead levels are still high in several cities, reaching an average of 1.68 microg m(-3) in Xi 'an. High correlations of lead with arsenic and sulfate concentrations indicate that much of it derives from coal combustion, rather than leaded fuels, which were phased out by calendar year 2000. Although limited fugitive dust markers were available, scaling of iron by its ratios in source profiles shows -20% of PM2.5 deriving from fugitive dust in most of the cities. Multipollutant control strategies will be needed that address incomplete combustion of coal and biomass, engine exhaust, and fugitive dust, as well as sulfur dioxide, oxides of nitrogen, and ammonia gaseous precursors for ammonium sulfate and ammonium nitrate. IMPLICATIONS PM2.5 mass and chemical composition show large contributions from carbon, sulfate, nitrate, ammonium, and fugitive dust during winter and summer and across fourteen large cities. Multipollutant control strategies will be needed that address both primary PM2.5 emissions and gaseous precursors to attain China's recently adopted PM2.5 national air quality standards.
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Affiliation(s)
- Jun-Ji Cao
- Key Lab of Aerosol, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi 'an, China.
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Hu Y, Odman MT, Russell AG. Top-down analysis of the elemental carbon emissions inventory in the United States by inverse modeling using Community Multiscale Air Quality model with decoupled direct method (CMAQ-DDM). ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009jd011987] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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9
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Hidy GM. Surface-level fine particle mass concentrations: from hemispheric distributions to megacity sources. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2009; 59:770-789. [PMID: 19645262 DOI: 10.3155/1047-3289.59.7.770] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Since 1990, basic knowledge of the "chemical climate" of fine particles, has greatly improved from Junge's compilation from the 1960s. A worldwide baseline distribution of fine particle concentrations on a synoptic scale of approximately 1000 km can be estimated at least qualitatively from measurements. A geographical distribution of fine particle characteristics is deduced from a synthesis of a variety of disparate data collected at ground level on all continents, especially in the northern hemisphere. On the average, the regional mass concentrations range from 1 to 80 microg/m3, with the highest concentrations in regions of high population density and industrialization. Fine particles by mass on a continental and hemispheric spatial scale are generally dominated by non-sea salt sulfate (0.2 to approximately 20 microg/m3, or approximately 25%) and organic carbon (0.2-> 10 microg/m3, or approximately 25%), with lesser contributions of ammonium, nitrate, elemental carbon, and elements found in sea salt or soil dust. The crustal and trace metal elements contribute a varied amount to fine particle mass depending on location, with a larger contribution in marine conditions or during certain events such as dust storms or volcanic disturbances. The average distribution of mass concentration and major components depends on the proximity to areal aggregations of sources, most of which are continental in origin, with contributions from sea salt emissions in the marine environment. The highest concentrations generally are within or near very large population and industrial centers, especially in Asia, including parts of China and India, as well as North America and Europe. Natural sources of blowing dust, sea salt, and wildfires contribute to large, intermittent spatial-scale particle loadings beyond these ranges. A sampling of 10 megacities illustrates a range of characteristic particle composition, dependent on local and regional sources. Long-range transport of pollution from spatially aggregated sources over hundreds of kilometers creates persistent regional- and continental-scale gradients of mass concentration, sulfate, and carbon species especially in the northern hemisphere. Data are sparse in the southern hemisphere, especially beyond 45 degrees S, but are generally very low in mass concentrations.
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10
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Marmer E, Langmann B. Aerosol modeling over Europe: 1. Interannual variability of aerosol distribution. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd008113] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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Tsyro S, Simpson D, Tarrasón L, Klimont Z, Kupiainen K, Pio C, Yttri KE. Modeling of elemental carbon over Europe. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd008164] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Hitzenberger R, Ctyroky P, Berner A, Tursic J, Podkrajsek B, Grgić I. Size distribution of black (BC) and total carbon (TC) in Vienna and Ljubljana. CHEMOSPHERE 2006; 65:2106-13. [PMID: 16875711 DOI: 10.1016/j.chemosphere.2006.06.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2005] [Revised: 06/13/2006] [Accepted: 06/14/2006] [Indexed: 05/11/2023]
Abstract
During two campaigns in winter 2004, size segregated impactor samples (0.1-10 microm) and filter samples were taken in two Central European cities (Vienna, Austria and Ljubljana, Slovenia). The impactor samples were analyzed for major inorganic ions and short-chain organic acids, total carbon (TC) and black carbon (BC). Maximum concentrations of total mass were 71.6 microg m(-3) in Vienna and 73.1 microg m(-3) in Ljubljana. Minimum concentrations in Vienna were only half those in Ljubljana. The BC content of the aerosol was similar (ca. 8%), but the BC/TC ratio was higher in Vienna than in Ljubljana (0.39 vs. 0.29), reflecting the different contribution of diesel traffic emissions. The mass median diameters of the submicron size distributions of all major fractions (total mass, TC, BC and SO(4)(2-)) were smaller in Vienna (0.43 microm, 0.41 microm, 0.38 microm and 0.48 microm, respectively) than in Ljubljana (0.55 microm, 0.44 microm, 0.42 microm and 0.60 microm, respectively). Impactor/filter ratios for total mass were 0.79 in Vienna and 0.82 in Ljubljana, while the ratios for BC were 0.56 in Vienna and 0.49 in Ljubljana. An estimation of the mixing state of accumulation mode BC indicated that 33% and 37% of BC, respectively, are mixed externally to the aerosol in the accumulation size range in Vienna and Ljubljana.
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Affiliation(s)
- R Hitzenberger
- University of Vienna, Institute for Experimental Physics, Boltzmanngasse 5, A-1090 Vienna, Austria.
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13
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Hitzenberger R, Petzold A, Bauer H, Ctyroky P, Pouresmaeil P, Laskus L, Puxbaum H. Intercomparison of thermal and optical measurement methods for elemental carbon and black carbon at an urban location. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:6377-83. [PMID: 17120568 DOI: 10.1021/es051228v] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Despite intensive efforts during the past 20 years, no generally accepted standard method exists to measure black carbon (BC) or elemental carbon (EC). Data on BC and EC concentrations are method specific and can differ widely (e.g. Schmid et al., 2001, ten Brink et al., 2004). In this study, a comprehensive set of methods (both optical and thermal) is compared. Measurements were performed under urban background conditions in Vienna, Austria, a city heavily impacted by diesel emissions. Filter and impactor samples were taken during 3 weeks in summer 2002 and analyzed for EC with thermal methods: a modified Cachier method (Cachier et al., 1989), a thermal-optical method (Schmid et al., 2001), and the VDI method (VDI, 1996); for BC with optical methods: a filter transmission method and the integrating sphere method (Hitzenberger et al., 1996); and for total carbon (TC) with a combustion method (Puxbaum and Rendl, 1983). The online methods aethalometer (Hansen et al., 1984) and the multiangle absorption photometer MAAP (Petzold et al., 2002) to measure BC were also used. The average values of BC and EC obtained with the methods agreed within their standard deviations. A conversion table was set up to allow comparisons between data measured elsewhere under urban background conditions (with similar source characteristics) with different instruments. An approach to estimate the absorption coefficient from attenuation data is derived so that existing records of aethalometer data in urban environments may be used to obtain also the absorption coefficients.
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Affiliation(s)
- R Hitzenberger
- Institute for Experimental Physics, University of Vienna, Boltzmanng. 5, A-1090 Vienna, Austria.
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14
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Szidat S, Jenk TM, Synal HA, Kalberer M, Wacker L, Hajdas I, Kasper-Giebl A, Baltensperger U. Contributions of fossil fuel, biomass-burning, and biogenic emissions to carbonaceous aerosols in Zurich as traced by14C. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006590] [Citation(s) in RCA: 269] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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15
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Kondo Y, Komazaki Y, Miyazaki Y, Moteki N, Takegawa N, Kodama D, Deguchi S, Nogami M, Fukuda M, Miyakawa T, Morino Y, Koike M, Sakurai H, Ehara K. Temporal variations of elemental carbon in Tokyo. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006257] [Citation(s) in RCA: 144] [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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16
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Katrib Y, Biskos G, Buseck PR, Davidovits P, Jayne JT, Mochida M, Wise ME, Worsnop DR, Martin ST. Ozonolysis of Mixed Oleic-Acid/Stearic-Acid Particles: Reaction Kinetics and Chemical Morphology. J Phys Chem A 2005; 109:10910-9. [PMID: 16331935 DOI: 10.1021/jp054714d] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ozonolysis of mixed oleic-acid/stearic-acid (OL/SA) aerosol particles from 0/100 to 100/0 wt % composition is studied. The magnitude of the divergence of the particle beam inside an aerosol mass spectrometer shows that, in the concentration range 100/0 to 60/40, the mixed OL/SA particles are liquid prior to reaction. Upon ozonolysis, particles having compositions of 75/25 and 60/40 change shape, indicating that they have solidified during reaction. Transmission electron micrographs show that SA(s) forms needles. For particles having compositions of 75/25, 60/40, and greater SA content, the reaction kinetics exhibit an initial fast decay of OL for low O(3) exposure with no further loss of OL at higher O(3) exposures. For compositions from 50/50 to 10/90, the residual OL concentration remains at 28 +/- 2% of its initial value. The initial reactive uptake coefficient for O(3), as determined by OL loss, decreases linearly from 1.25 (+/-0.2) x 10(-3) to 0.60 (+/-0.15) x 10(-3) for composition changes of 100/0 to 60/40. At 50/50 composition, the uptake coefficient drops abruptly to 0.15 (+/-0.1) x 10(-3), and there are no further changes with increased SA content. These observations can be explained with a combination of three postulates: (1) Unreacted mixed particles remain as supersaturated liquids up to 60/40 composition, and the OL in this form rapidly reacts with O(3). (2) SA, as it solidifies, locks into its crystal structure a significant amount of OL, and this OL is completely inaccessible to O(3). (3) Accompanying crystallization, some stearic acid molecules connect as a filamentous network to form a semipermeable gel containing liquid OL but with a reduced uptake coefficient because of the decrease in molecular diffusivity in the gel. An individual particle of 50/50 to 90/10 is hypothesized as a combination of SA crystals having OL impurities (postulate 2) that are partially enveloped by an SA/OL gel (postulate 3) to explain (a) the abrupt drop in the uptake coefficient from 60/40 to 50/50 and (b) the residual OL content even after high ozone exposure. The results of this study, pointing out the important effects of particle phase, composition, and morphology on chemical reactivity, contribute to an improved understanding of the aging processes of atmospheric aerosol particles.
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Affiliation(s)
- Y Katrib
- Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
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Hakami A, Henze DK, Seinfeld JH, Chai T, Tang Y, Carmichael GR, Sandu A. Adjoint inverse modeling of black carbon during the Asian Pacific Regional Aerosol Characterization Experiment. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004jd005671] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. Hakami
- Departments of Chemical Engineering and Environmental Science and Engineering; California Institute of Technology; Pasadena California USA
| | - D. K. Henze
- Departments of Chemical Engineering and Environmental Science and Engineering; California Institute of Technology; Pasadena California USA
| | - J. H. Seinfeld
- Departments of Chemical Engineering and Environmental Science and Engineering; California Institute of Technology; Pasadena California USA
| | - T. Chai
- Center for Global and Regional Environmental Research; University of Iowa; Iowa City Iowa USA
| | - Y. Tang
- Center for Global and Regional Environmental Research; University of Iowa; Iowa City Iowa USA
| | - G. R. Carmichael
- Center for Global and Regional Environmental Research; University of Iowa; Iowa City Iowa USA
| | - A. Sandu
- Department of Computer Science; Virginia Polytechnic Institute and State University; Blacksburg Virginia USA
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