Journal of Atmospheric Chemistry最新文献

{"title":"Seasonal and annual trends of carbonaceous species of PM10 over a megacity Delhi, India during 2010–2017","authors":"S. K. Sharma,&nbsp;T. K. Mandal,&nbsp;A. Sharma,&nbsp; Saraswati,&nbsp;Srishti Jain","doi":"10.1007/s10874-018-9379-y","DOIUrl":"https://doi.org/10.1007/s10874-018-9379-y","url":null,"abstract":"<p>PM₁₀ samples were collected to characterize the seasonal and annual trends of carbonaceous content in?PM₁₀ at an urban site of megacity Delhi, India from January 2010 to December 2017. Organic carbon (OC) and elemental carbon (EC) concentrations were quantified by thermal-optical transmission (TOT) method of PM₁₀ samples collected at Delhi. The average concentrations of PM₁₀, OC, EC and TCA (total carbonaceous aerosol) were 222?±?87 (range: 48.2–583.8?μg?m^?3), 25.6?±?14.0 (range: 4.2–82.5?μg?m^?3), 8.7?±?5.8 (range: 0.8–35.6?μg?m^?3) and 54.7?±?30.6?μg?m^?3 (range: 8.4–175.2?μg?m^?3), respectively during entire sampling period. The average secondary organic carbon (SOC) concentration ranged from 2.5–9.1 μg?m^?3 in PM₁₀, accounting from 14 to 28% of total OC mass concentration of PM₁₀. Significant seasonal variations were recorded in concentrations of PM₁₀, OC, EC and TCA with maxima during winter and minima during monsoon seasons. In the present study, the positive linear trend between OC and EC were recorded during winter (<i>R</i>^<i>2</i>?=?0.53), summer (<i>R</i>^<i>2</i>?=?0.59) and monsoon (<i>R</i>^<i>2</i>?=?0.78) seasons. This behaviour suggests the contribution of similar sources and common atmospheric processes in both the fractions. OC/EC weight?ratio suggested that vehicular emissions, fossil fuel combustion and biomass burning could be the major sources of carbonaceous aerosols of PM₁₀ at the megacity Delhi, India. Trajectory analysis indicates that the air mass approches to the sampling site is mainly from Indo Gangetic plain (IGP) region (Uttar Pradesh, Haryana and Punjab etc.), Thar desert, Afghanistan, Pakistan and surrounding areas.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 3","pages":"305 - 318"},"PeriodicalIF":2.0,"publicationDate":"2018-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-018-9379-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4274503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Size-resolved characteristics of inorganic ionic species in atmospheric aerosols at a regional background site on the South African Highveld","authors":"Andrew D. Venter,&nbsp;Pieter G. van Zyl,&nbsp;Johan P. Beukes,&nbsp;Jan-Stefan Swartz,&nbsp;Miroslav Josipovic,&nbsp;Ville Vakkari,&nbsp;Lauri Laakso,&nbsp;Markku Kulmala","doi":"10.1007/s10874-018-9378-z","DOIUrl":"https://doi.org/10.1007/s10874-018-9378-z","url":null,"abstract":"<p>Aerosols consist of organic and inorganic species, and the composition and concentration of these species depends on their sources, chemical transformation and sinks. In this study an assessment of major inorganic ions determined in three aerosol particle size ranges collected for 1?year at Welgegund in South Africa was conducted. SO₄^2? and ammonium (NH₄⁺) dominated the PM₁ size fraction, while SO₄^2? and nitrate (NO₃) dominated the PM_1–2.5 and PM_2.5–10 size fractions. SO₄^2? had the highest contribution in the two smaller size fractions, while NO₃^? had the highest contribution in the PM_2.5–10 size fraction. SO₄^2? and NO₃^? levels were attributed to the impacts of aged air masses passing over major anthropogenic source regions. Comparison of inorganic ion concentrations to levels thereof within a source region influencing Welgegund, indicated higher levels of most species within the source region. However, the comparative ratio of SO₄^2? was significantly lower due to SO₄^2? being formed distant from SO₂ emissions and submicron SO₄^2? having longer atmospheric residencies. The PM at Welgegund was determined to be acidic, mainly due to high concentrations of SO₄^2?. PM₁ and PM_1–2.5 fractions revealed a seasonal pattern, with higher inorganic ion concentrations measured from May to September. Higher concentrations were attributed to decreased wet removal, more pronounced inversion layers trapping pollutants, and increases in household combustion and wild fires during winter. Back trajectory analysis also revealed higher concentrations of inorganic ionic species corresponding to air mass movements over anthropogenic source regions.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 3","pages":"285 - 304"},"PeriodicalIF":2.0,"publicationDate":"2018-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-018-9378-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4953856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trace ambient levels of particulate mercury and its sources at a rural site near Delhi","authors":"Anita Kumari,&nbsp;Umesh Kulshrestha","doi":"10.1007/s10874-018-9377-0","DOIUrl":"https://doi.org/10.1007/s10874-018-9377-0","url":null,"abstract":"<p>Atmospheric particle-bound mercury levels were measured in PM₁₀ aerosols (HgP) at a rural site (Mahasar, Haryana) during winter 2014–15 and summer 2015. The PM₁₀ HgP was determined by?using Differential Pulse Anodic Stripping Voltammetry through standard addition methods while the trace metals were determined by using an Atomic Absorption Spectroscopy. The mass concentrations of HgP varied from 591 to 1533?pg/m³ with an average of 1009?±?306?pg/m³ during the winter, while the mass concentrations of HgP varied from 43 to 826?pg/m³ with an average of 320?±?228?pg/m³ during the summer. However, it is difficult to assess whether these levels are harmful or not because there is no standard value available as National Ambient Air Quality Standard. The higher concentrations of HgP during winters were possibly due to favourable local meteorological conditions for the stagnation of particulate matter in the lower atmosphere and the increased emissions from existing natural or anthropogenic sources, regional sources and long-range transportation. Relatively low concentrations of HgP during summer might be due to increased mixing heights as well as scavenging effect because some light to heavy rain events were observed during summer time sampling. However, among other metals determined, the concentration of HgP was the lowest during both the seasons. The study may be useful in assessing the health impacts of PM₁₀ HgP and other metals.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 4","pages":"335 - 355"},"PeriodicalIF":2.0,"publicationDate":"2018-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-018-9377-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4937306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive study on the surface chemistry of particulate matter collected from Jeddah, Saudi Arabia","authors":"Asim Jilani,&nbsp;Syed Zajif Hussain,&nbsp;Mohd Hafiz Dzarfan Othman,&nbsp;Usama Zulfiqar,&nbsp;Muhammad Bilal Shakoor,&nbsp;Imran Ullah Khan,&nbsp;Javed Iqbal,&nbsp;Attieh A. Al-Ghamdi,&nbsp;Ahmed Alshahrie","doi":"10.1007/s10874-018-9376-1","DOIUrl":"https://doi.org/10.1007/s10874-018-9376-1","url":null,"abstract":"<p>In this work, the X-ray Photoelectron Spectroscopy (XPS) technique is utilized to analyze the surface chemical composition of particulate matter (PM) which was collected from various locations at Jeddah, Saudi Arabia. The main elements found on the surface of PM are carbon (C), oxygen (O) and silicon (Si) with combined percentage of 89.4–94.9 while traces of nitrogen (N), calcium (Ca), aluminum (Al), sodium (Na), chlorine (Cl), manganese (Mg), and sulfur (S) were also present. The analyzed XPS chemical state of C, O and Si was further used to determine their bonding with other elements occurring over the surface of PM. Carbon was found in the form of carbides (18.86%), fluorides (2.39%) and carbonates (78.75%); oxygen was observed as oxides (21.05%) and hydroxides (73.42%) of other metals; and silicon was detected as silicones (12.16%), nitrides (82.53%) and silicates (5.25%). The particle size of a PM is also of great concern for health issues, and thus has been investigated by the Field Emission Scanning Electron Microscope (FESEM). The Energy Dispersive X-ray Spectroscopy (EDS) was employed for cross verification of detected elements by XPS.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 3","pages":"271 - 283"},"PeriodicalIF":2.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-018-9376-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4253641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insignificant impact of freezing and compaction on iron solubility in natural snow","authors":"Pami Mukherjee,&nbsp;Mihaela Glamoclija,&nbsp;Yuan Gao","doi":"10.1007/s10874-018-9375-2","DOIUrl":"https://doi.org/10.1007/s10874-018-9375-2","url":null,"abstract":"<p>To explore the freezing effect on iron (Fe) solubility in natural environments, especially in Polar regions, event based freshly fallen snow samples were collected at Newark, New Jersey on the US East Coast for two consecutive winter seasons (2014–2015 and 2015–2016). These samples were analyzed for the concentrations of soluble iron (Fe_sol) using UV-Vis Spectroscopy and filterable iron (Fe_fil) and total iron (Fe_tot) using Atomic Absorption Spectroscopy. The average fractional solubility of the Fe_sol (the portion that passes through a 0.22?μm pore-size filter) with respect to the total Fe in the samples was 23.3?±?12.2%, with the majority of the soluble Fe being present as Fe(III). Approximately 48.5% of the total Fe existed as Fe_fil (the portion that passes through 0.45?μm pore size filter media). No significant correlation was found between the soluble ionic species and soluble Fe. Six snow events were kept frozen for 10?days, and analyzed in periodic intervals to study the post-freezing modification in Fe solubility. Events 1 and 2 showed increasing trend in the soluble Fe concentrations; however, the events 5, 6, 7, and 8 showed no noticeable increments. The pattern shown in Events 1 and 2 is associated with high fraction of Fe_fil and one unit pH drop, suggesting that the freeze-induced modification in Fe solubility could be linked with the amount of Fe_fil and the acidity change in the samples. To further investigate the freeze-induced compaction of particles, samples from three events 6, 7, and 10 were analyzed by SEM-STEM-EDS microscopy, and the results showed that due to freezing, in general, the particles in the ice-melt counterparts tend to compact and cluster and form larger aggregates compared to the particles in snow-melt. These results show, despite the freeze-induced compaction in snow was observed from STEM images, the snow freezing might not have significant effect in increasing Fe solubility from materials in the snow. These results further suggest that freezing process with fresh snow in high-latitude regions may not impose significant modification on Fe solubility in snow.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 3","pages":"247 - 270"},"PeriodicalIF":2.0,"publicationDate":"2018-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-018-9375-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4762017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Re-examine the APEC blue in Beijing 2014","authors":"Ting Wang,&nbsp;Pucai Wang,&nbsp;François Hendrick,&nbsp;Michel Van Roozendael","doi":"10.1007/s10874-018-9374-3","DOIUrl":"https://doi.org/10.1007/s10874-018-9374-3","url":null,"abstract":"<p>APEC blue was coined to describe the impact of short-term curbs on air pollution during the Asian-Pacific Economic Cooperation (APEC) Summit organized in Beijing in November 2014 and has been a hot topic among both general public and scientific sector in China. The consensus that gaseous agents NO₂ and SO₂ are greatly reduced in response to the control and restriction strategies implemented during the Summit period is shared by earlier literature. However, the re-examination of APEC blue conducted in the present study comes to a more contrasted conclusion. The remarkable drop in NO₂ abundances is confirmed in terms of both surface concentration and vertical column, whereas corresponding SO₂ changes are found to be marginal and not statistically significant, indicating that the decline of SO₂ was more tied to natural or random variability rather than externally forced. To explain the contrasted responses of NO₂ and SO₂ during the APEC summit, short-term variations of these species are further placed in the context of a longer term perspective, which reveals a striking contrast in the pathways of the secular tendency in NO₂ and SO₂ emissions and corresponding measured abundances of both pollutants. On the one hand, NO₂ emissions exhibit a sharp rise by 30–50% from 2006-2010 to 2011–2014; on the other hand, SO₂ emissions have undergone a gradual decrease in the last decade and have currently returned to their pre-2000 level. Therefore, short-term control measures are expected to be more effective in reducing the levels of NO₂ than SO₂.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 2","pages":"235 - 246"},"PeriodicalIF":2.0,"publicationDate":"2018-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-018-9374-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4891983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbonaceous and inorganic species in PM10 during wintertime over Giridih, Jharkhand (India)","authors":"S. K. Sharma,&nbsp;T. K. Mandal,&nbsp;A. K. De,&nbsp;N. C. Deb,&nbsp;Srishti Jain,&nbsp;Mohit Saxena,&nbsp;S. Pal,&nbsp;A. K. Choudhuri,&nbsp; Saraswati","doi":"10.1007/s10874-017-9373-9","DOIUrl":"https://doi.org/10.1007/s10874-017-9373-9","url":null,"abstract":"<p>Ambient concentrations of organic carbon (OC), elemental carbon (EC) and water soluble inorganic ionic components (WSIC) of PM₁₀ were studied at Giridih, Jharkhand, a sub-urban site near the Indo Gangatic Plain (IGP) of India during two consecutive winter seasons (November 2011–February 2012 and November 2012–February 2013). The abundance of carbonaceous and water soluble inorganic species of PM₁₀ was recorded at the study site of Giridih. During winter 2011–12, the average concentrations of PM₁₀, OC, EC and WSIC were 180.2?±?46.4; 37.2?±?6.2; 15.2?±?5.4 and 18.0?±?5.1?μg m^?3, respectively. Similar concentrations of PM₁₀, OC, EC and WSIC were also recorded during winter 2012–13. In the present case, a positive linear trend is observed between OC and EC at sampling site of Giridih indicates the coal burning, as well as dispersed coal powder and vehicular emissions may be the source of carbonaceous aerosols. The principal components analysis (PCA) also identifies the contribution of coal burning??+?soil dust, vehicular emissions?+?biomass burning and seconday aerosol to PM₁₀ mass concentration at the study site. Backward trajectoy and potential source contributing function (PSCF) analysis indicated that the aerosols being transported to Giridih from upwind IGP (Punjab, Haryana, Uttar Pradesh and Bihar) and surrounding region.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 2","pages":"219 - 233"},"PeriodicalIF":2.0,"publicationDate":"2017-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-017-9373-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4834784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of brown carbon constituents of benzene secondary organic aerosol aged with ammonia","authors":"Mingqiang Huang,&nbsp;Jun Xu,&nbsp;Shunyou Cai,&nbsp;Xingqiang Liu,&nbsp;Weixiong Zhao,&nbsp;Changjin Hu,&nbsp;Xuejun Gu,&nbsp;Li Fang,&nbsp;Weijun Zhang","doi":"10.1007/s10874-017-9372-x","DOIUrl":"https://doi.org/10.1007/s10874-017-9372-x","url":null,"abstract":"<p>Nitrogen-containing organic compounds (NOC) formed from secondary organic aerosols (SOA) age via reaction with reduced nitrogen species are a vital class of brown carbon compounds. NOC compounds from ammonia (NH₃) gas-aging of benzene SOA were investigated in present study, and the experiments were performed by irradiating benzene/CH₃ONO/NO/NH₃ air mixtures in a home-made smog chamber. The particulate NOC products of aged benzene SOA in the presence of NH₃ were measured by UV-Vis spectrophotometer, attenuated total reflectance-Fourier transform infrared (ATR-FTIR), and aerosol laser time-of-flight mass spectrometer (ALTOFMS) coupled with Fuzzy C-Means (FCM) clustering algorithm, respectively. Experimental results demonstrated that NH₃ has significant promotion effect on benzene SOA formation. Organic ammonium salts, such as ammonium glyoxylate, ammonium 6-oxo-2,4-hexadienoiclate, which are formed from NH₃ reactions with gaseous organic acids were detected as the major particulate NOC products of NH₃-aged benzene SOA. 1H–imidazole, 1H–imidazole-2-carbaldehyde and other imidazole products via the heterogeneous reactions between NH₃ and dialdehydes of benzene SOA were successfully detected as important brown carbon constituents. The formation of imidazole products suggests that some ambient particles contained organonitrogen compounds may be come from this mechanism. The results of this study may provide valuable information for discussing NH₃ deposition and SOA aging mechanisms.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 2","pages":"205 - 218"},"PeriodicalIF":2.0,"publicationDate":"2017-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-017-9372-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5131663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of precursor emissions on ground level ozone concentration during summer season in Poland","authors":"Kinga Wałaszek,&nbsp;Maciej Kryza,&nbsp;Małgorzata Werner","doi":"10.1007/s10874-017-9371-y","DOIUrl":"https://doi.org/10.1007/s10874-017-9371-y","url":null,"abstract":"<p>Three online coupled chemical transport model simulations were analyzed for three summer months of 2015 in Poland. One of them was run with default emission inventory, the other two with NO_x and VOC emissions reduced by 30%, respectively. Obtained ozone concentrations were evaluated with data from air quality measurement stations and ozone sensitivity to precursor emissions was estimated by ozone concentration differences between simulations and with the use of indicator ratios. They were calculated based on modeled mixing ratios of ozone, total reactive nitrogen and its components, nitric acid and hydrogen peroxide. The results show that the model overestimates ozone concentrations with the largest errors in the morning and evening, which is primarily related to the way vertical mixing is resolved by the model. Better model performance for ozone is achieved in rural than urban environment, as PBL and mixing mechanisms play more significant role in urban areas. Modeled ozone shows mixed sensitivity to precursor concentrations, similarly to other European regions, but indicator ratios have different values than are found in literature, particularly H₂O₂/HNO₃ is larger than in southern Europe. However, indicator ratios often differ between locations and transition values need to be established individually for a given region.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 2","pages":"181 - 204"},"PeriodicalIF":2.0,"publicationDate":"2017-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-017-9371-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4911519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water-soluble inorganic ions of size-differentiated atmospheric particles from a suburban site of Mexico City","authors":"Telma Castro,&nbsp;Oscar Peralta,&nbsp;Dara Salcedo,&nbsp;José Santos,&nbsp;María I. Saavedra,&nbsp;María L. Espinoza,&nbsp;Alejandro Salcido,&nbsp;Ana-Teresa Celada-Murillo,&nbsp;Susana Carreón-Sierra,&nbsp;Harry Álvarez-Ospina,&nbsp;Giovanni Carabali,&nbsp;Valter Barrera,&nbsp;Sasha Madronich","doi":"10.1007/s10874-017-9369-5","DOIUrl":"https://doi.org/10.1007/s10874-017-9369-5","url":null,"abstract":"<p>During the MILAGRO campaign, March 2006, eight-stage cut impactors were used to sample atmospheric particles at Tecámac (T1 supersite), towards the northeast edge of the Mexico City Metropolitan Area, collecting fresh local emissions and aged pollutants produced in Mexico City. Particle samples were analyzed to determine total mass concentrations of Ca²⁺, Mg²⁺, NH₄\u0000 ⁺, K⁺, Cl^?, SO₄\u0000 ^2?, and NO₃\u0000 ^?. Average concentrations were 22.1?±?7.2?μg m^?3 for PM₁₀ and 18.3?±?6.2?μg m^?3 for PM_1.8. A good correlation between PM₁₀ and PM_1.8, without influence from wind patterns, indicates that local emissions are more important than the city’s pollution transported to the site, despite the fact that Tecámac is just 40?km away from Mexico City. A lack of diurnal patterns in the PM_2.5/PM_1.8 ratio supports this conclusion. The inorganic composition of particles suggests that vehicles, soil resuspension, and industries are the main pollutant sources. Finally, the particles were found to be neutralized, in agreement with observations in the Mexico City Metropolitan Area.</p>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"75 2","pages":"155 - 169"},"PeriodicalIF":2.0,"publicationDate":"2017-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s10874-017-9369-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4815866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}