Aerosol Science and Engineering最新文献

{"title":"Retrieval of Broadband Optical Properties from Ambient Aerosols Measurements Using Inverse Mie Calculations","authors":"Aiswarya Saseendran,&nbsp;Shebin John,&nbsp;Anoop Pakkattil,&nbsp;Arun P. Thomas,&nbsp;Sushmitha Adiga,&nbsp;Jun Chen,&nbsp;Claudio Mazzoleni,&nbsp;Deepa Viswanath,&nbsp;Ravi Varma","doi":"10.1007/s41810-021-00128-z","DOIUrl":"10.1007/s41810-021-00128-z","url":null,"abstract":"<div><p>The role of atmospheric aerosols in earth’s radiative balance is crucial. A thorough knowledge about the spectral optical properties of various types of aerosols is necessary to quantify the net radiative forcing produced by aerosol–light interactions. In this study, we exploited an open-source inverse algorithm based on the Python—PyMieScatt survey iteration method, to retrieve the wavelength dependent Mie-equivalent complex refractive indices of ambient aerosols. This method was verified by obtaining the broadband complex refractive indices of monodisperse polystyrene latex spheres and polydisperse common salt aerosols, using laboratory data collected with a supercontinuum broadband cavity enhanced extinction spectrometer operating in the 420–540 nm wavelength range. Field measurements of ambient aerosol were conducted using a similar cavity enhanced extinction spectrometer (IBBCEES) operating in the wavelength range of 400–550 nm, a multi-wavelength aethalometer, and a scanning mobility particle sizer, in Changzhou city, People’s Republic of China. The absorption coefficients for the entire wavelength range were retrieved using the absorption Ångström exponents calculated from a pair of measured absorption coefficients at known wavelengths. The survey iteration method takes scattering and absorption coefficients, wavelength, and size distributions as inputs; and it calculates the Mie-equivalent wavelength dependent complex refractive index (RI = <i>n</i> ± <i>ik</i>) and estimated errors. The retrieved field RI values ranged from 1.66 ≤ <i>n</i> ≤ 1.80 to 1.65 ≤ <i>n</i> ≤ 1.86 and from 0.036 ≤ <i>k</i> ≤ 0.038 to 0.062 ≤ <i>k</i> ≤ 0.067 in the wavelength range (400–550 nm), for low and high aerosol loading conditions, respectively. Additionally, we derived the spectral dependencies of scattering and absorption coefficients along with the <i>n</i> and <i>k</i> Ångström exponents (<i>AE</i>). The <i>nAE</i> and <i>kAE</i> estimated values suggest a stronger wavelength dependence for aerosol light scattering compared to absorption, and a decreasing trend for the spectrally dependent single scattering albedo during both loading conditions. The extremum of errors in the retrieved <i>n</i> and <i>k</i> values were quantified by considering (a) uncertainties in input parameters in the broad spectral region (400–550 nm), (b) using CAPS extinction values at 530 nm and (c) an estimated size distribution incorporating the coarse particles (at 530 nm).</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50043060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indoor Air Quality Monitoring of Urban and Rural Households of a North Indian City During Cooking Hours","authors":"Deeksha Shukla,&nbsp;Venkatesh Dutta","doi":"10.1007/s41810-021-00126-1","DOIUrl":"10.1007/s41810-021-00126-1","url":null,"abstract":"<div><p>The present study aims to study the indoor and outdoor air quality in an urban center and its immediate rural areas. The measurements of particulate matter (PM₁₀ and PM_2.5) and the Air Quality Index (AQI) during cooking hours in the morning, daytime, and evening, using a real-time portable air sampler were performed as a part of the study. Five residential colonies in urban and rural localities of a North Indian city Lucknow, covering a total of sixty households (HHs), were selected for detailed sampling over a period of two months (February and March 2018). A major difference in the cooking pattern was observed in urban and rural localities in terms of the use of cooking fuels. The average indoor PM_2.5 concentrations in urban and rural HHs were 115.4 µg/m³ and 337.2 µg/m³, respectively. These values were 1.3 and 7.8 times higher than the outdoor PM_2.5 concentration levels. Similarly, the average indoor PM₁₀ concentrations in urban and rural HHs were 178.3 µg/m³ and 362.4 µg/m³, respectively. These values were 1.2 and 4.8 times higher than the outdoor levels. The average AQI be the highest (368.8) for rural indoors, primarily due to biomass burning, and the lowest (84.9) for rural outdoors during the sampling period. A majority (&gt; 70%) of the rural HHs, with women being the most susceptible groups for the exposure, reported ailments like prolonged coughing and eye irritation during cooking hours, while urban HHs were relatively better off. The difference in the indoor and outdoor urban and rural air quality was observed to be the least during the daytime and evening, indicating the variations in emission patterns during the cooking hours. It is expected that the outcome of this study will help in taking progressive measures to reduce the emission of particulate matter while cooking, especially in vulnerable rural households.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50035537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response of the Equatorial Atlantic Cold Tongue to Stratospheric Aerosol Geoengineering","authors":"Y. W. Pomalegni,&nbsp;C. Y. Da-Allada,&nbsp;Z. Sohou,&nbsp;E. Baloïtcha,&nbsp;E. A. Alamou,&nbsp;F. M. Awo,&nbsp;F. Bonou,&nbsp;I. Biao,&nbsp;E. Obada,&nbsp;J. E. Zandagba,&nbsp;S. Tilmes,&nbsp;P. J. Irvine","doi":"10.1007/s41810-021-00127-0","DOIUrl":"10.1007/s41810-021-00127-0","url":null,"abstract":"<div><p>By increasing Earth-atmosphere system albedo, Stratospheric Aerosol Geoengineering (SAG) using sulfur dioxide is an artificial potential means, with the goal to mitigate the global warming effects. In this study, we used the simulations from Geoengineering Large Ensemble project realized under the climate change scenario of Representative Concentration Pathway 8.5 (RCP8.5), to investigate the potential impact of SAG on the Sea Surface Temperature (SST) in Equatorial Atlantic Cold Tongue (EACT) and the physical processes driving these changes. Results reveal that in the EACT region, under RCP8.5, SST warms significantly (compared to present‐day climate) with a maximum of 1.7 °C in July, and this increase in SST is mainly due to the local processes related to the weakening of vertical mixing at the base of the mixed layer. This reduction of the vertical mixing is associated to the diminution of the vertical shear from July to April and to the increase of ocean stratification from May to June. However, under SAG, SST decreases significantly throughout the year (compared to present‐day climate) with a maximum cooling of − 0.4 °C in the cold tongue period (May–June). This SST cooling is mainly associated with the non-local processes related to intensification of the westerly equatorial Atlantic wind stress. Finally, results show that the use of SAG to offset all global warming under RCP8.5 results in a slight over compensation of SST in the EACT region.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s41810-021-00127-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50034129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Etched Silicon Substrate on Structural, Morphological, and Optical Properties of Deposited ZnO Films via DC Sputtering","authors":"B. Abdallah,&nbsp;R. Hussin,&nbsp;W. Zetoune","doi":"10.1007/s41810-021-00122-5","DOIUrl":"10.1007/s41810-021-00122-5","url":null,"abstract":"<div><p>In this work, ZnO films are deposited by magnetron sputtering [using direct current (DC)], on polished silicon substrate Si(100) (non-etched), etched for 1 min, 5 min, 10 min and 15 min. The effect of etched silicon substrate on structural, morphological, and optical properties of ZnO films has been investigated. A new nanostructure can be obtained by mean of modification in morphology of substrate. The etching of the substrate was effectuated by means of dry plasma at different time and they compared with non-etched substrates. AFM and SEM images have been used to investigate the morphology behaviors of ZnO films growth on etched and non-etched silicon substrates. Optical properties were studied in details, photoluminescence (PL) showed that the intensity of ZnO films have been increased by increasing the substrate etching time from 0 to 15 min, which were associated with the crystallographic properties [for (002) orientation] using X-ray diffraction (XRD). That may be related to the decrease of grain size and roughness morphology increasing with the etching time. FTIR and MicroRaman spectra of films show vibrational modes characteristic of ZnO materials and they were related with morphology and structural of the films. In addition, the variation of ethylene glycol contact angle data (ECA) related to roughness of the ZnO films deposited on etched Si substrate at different times were studied. The ZnO films on etched substrate were interesting in optoelectronic purpose as well as for gas sensor in future work of our team.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s41810-021-00122-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50511237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational Fluid Dynamics Optimization of an Extraoral Vacuum Aerosol Cup for Airborne Disease Control in Dental Offices","authors":"Peter Liu","doi":"10.1007/s41810-021-00121-6","DOIUrl":"10.1007/s41810-021-00121-6","url":null,"abstract":"<div><p>Droplet and aerosol transmission of COVID-19 are the most important concerns in dental clinics, due to the generation of large amounts of infected aerosol and droplets mixed with patient’s saliva during the procedures. The current approach to prevent airborne disease transmission is an extraoral aerosol suction unit: a stand-alone vacuum module with a segmented arm and cup. Despite the need for disease control in dental offices, these units are rarely seen due to the loud noise produced by vacuum, bulky size, and high cost. This paper describes the aerodynamic design optimization of an affordable, 3D printable, Extraoral Vacuum Aerosol Cup (EVAC) that can be directly connected to existing standard 7/16″ central vacuum high-volume evacuator (HVE) valves used for intraoral saliva absorption in a dental office. These HVEs are typically unsuitable for extraoral suction due to their low vacuum force. However, they can be used for extraoral suction, if the cup attachment is aerodynamically optimized for maximum suction efficiency. Fifteen different designs of EVAC are proposed and their suction processes were simulated with computational fluid dynamics. Droplets of various sizes are released to mimic the droplets produced during dental operation. The suction performances of EVACs with different sizes and shapes were compared to find out the designs with optimal performance. Prototypes of the optimized EVAC are 3D printed and tested at a dental office. Development and manufacturing of such a device will largely reduce the COVID-19 infection risk, thus improving the safety protection for both patients and doctors at dental offices.</p><h3>Graphic abstract</h3>\u0000 <div><figure><div><div><picture><source><img></source></picture></div></div></figure></div>\u0000 </div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50522142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Theoretical Model of RGB Attenuation of Solar Radiation Components Under Strong Aerosol Pollution of the Atmosphere","authors":"Y. N. Aliyeva,&nbsp;K. A. Mammadova,&nbsp;A. N. Huseynova","doi":"10.1007/s41810-021-00120-7","DOIUrl":"10.1007/s41810-021-00120-7","url":null,"abstract":"<div><p>The urgency and significance of the formulation of the problem of creating a generalized model of attenuation of solar radiation in the visible range in the polluted atmosphere of large industrial cities has been substantiated. To build our own new model of attenuation of RGB components of solar radiation, we used the well-known theoretical position that with an increase in the average attenuation coefficient in the range from purely Rayleigh scattering to light scattering in strong fog, the ratio of partial attenuation coefficients of red/green and blue/green colors tends to unity. A mathematical model of attenuation of RGB components of solar radiation in a polluted atmosphere is proposed. It is shown that the proposed mathematical model allows changing all light components in attenuated solar radiation by selecting just one indicator of this model.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50473037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Air Quality at Public Transportation Stations/Stops: Contribution of Light Rail Transit to Reduce Air Pollution","authors":"Addis Bikis,&nbsp;Digvijay Pandey","doi":"10.1007/s41810-021-00119-0","DOIUrl":"10.1007/s41810-021-00119-0","url":null,"abstract":"<div><p>Air pollution from cars, vans and other different motor cars had observed in higher concentrations at public transportation stations. Now a day’s air pollutants from public transportation, industry, cooking from firewood and dust production alongside main roads in Addis Ababa is increasing and affecting human health. Individuals who live and work close to streets seem to have an expanded occurrence and openness to medical issues related to transportation air contamination. Appropriately, the Addis Ababa Light Rail Transit was the main current mass transit framework in Ethiopia just as in Sub Saharan Africa launched in 2015. Thus, this study aimed to know the air quality at LRT, bus, taxi and mixed stations through an air tracking device, and health effect at sampled public transportation stations. Air quality data include particulate matter (PM_2.5, PM₁₀), air quality index (AQI), carbon dioxide (CO₂), humidity and temperature with a half-hour observation through Air-Visual pro for every 24 purposively sampled stations from North to South LRT line. The average measured air quality indicated that higher than 35 μg/m³ PM_2.5 and 100 AQI, which is unhealthy. Regards to this, 30 persons were questioned at all stations. Seven hundred twenty (720) persons in total to know the health effect of those living/working in and around the stations. The findings indicated that out of 720 respondents, 324 (45%) have experienced to air quality-related diseases residing and working proximity to the stations. These suggested that the aged vehicles, land-use, dust and design of bus-stop shelter for waiting passengers have increased exposure to vehicles air pollution. Consequently, peoples are exposing to air quality-related respiratory diseases particularly unhealthy for sensitive groups.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s41810-021-00119-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50481879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring Air Quality in Nigeria: The Case of Center for Atmospheric Research-National Space Research and Development Agency (CAR-NASRDA)","authors":"Francis Olawale Abulude,&nbsp;Ifeoluwa Ayodeji Abulude","doi":"10.1007/s41810-021-00116-3","DOIUrl":"10.1007/s41810-021-00116-3","url":null,"abstract":"<div><p>Satellite is used to track air quality around the world to provide people with free air quality data. The data are released by global networks. A good example is the CAR-NASRDA network that provides real-time particulate matter data. The data (PM₁, PM_2.5, PM₁₀, temperature, and humidity) from CAR were used in the study. The data were obtained on NASRDA website, and cover a period of 5–7 months. The range results are depicted as follows: Lagos—PM₁ (15.98–604.09 µg/m³), PM_2.5 (23.23–847.75 µg/m³), PM₁₀ (25–753.8 µg/m³), temperature (80–109 °F), and relative humidity (12–77%); Osun—PM₁ (6.53–164.1 µg/m³), PM_2.5 (9.1–236.6 µg/m³), PM₁₀ (9.95–260.68 µg/m³), temperature (73.1–108.24 ^oF), and relative humidity (4.9–72%); Delta—PM₁ (8.23–273 µg/m³), PM_2.5 (12.11–487.36 µg/m³), PM₁₀ (12.96–552.51 µg/m³), temperature (74.62–109.59 °F), and relative humidity (10.7–60.85%); Kebbi—PM₁ (0–5373.5 µg/m³), PM_2.5 (µg/m³), PM₁₀ (µg/m³), temperature (6–125 °F), and relative humidity (0–49%), and FCT—PM₁ (0–847.84 µg/m³), PM_2.5 (0–1146.73 µg/m³), PM₁₀ (0–831 µg/m³), temperature (66–115 °F), and humidity (2–90%). When compared to international benchmarks, the findings are noticeably higher in this case. It has been discovered that PM values, temperature and relative humidity are correlated.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50001760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ozone Gas Inhibits SARS-CoV-2 Transmission and Provides Possible Control Measures","authors":"Junji Cao,&nbsp;Yecheng Zhang,&nbsp;Quanjiao Chen,&nbsp;Maosheng Yao,&nbsp;Rongjuan Pei,&nbsp;Yun Wang,&nbsp;Yang Yue,&nbsp;Yu Huang,&nbsp;Jing Wang,&nbsp;Wuxiang Guan","doi":"10.1007/s41810-021-00118-1","DOIUrl":"10.1007/s41810-021-00118-1","url":null,"abstract":"<div><p>The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused millions of deaths currently. Mounting effective responses to the pandemic have become top priorities for governments around the world. Laboratory experiments have confirmed for the first time that fumigation with ozone (O₃) at low O₃ doses (7500–15,000 μg m⁻³·min) can inhibit the SARS-CoV-2 and inactivate the virus at high O₃ doses (129,000 μg m⁻³·min). The RNA copy number of SARS-CoV-2 significantly decreased (95.9–97.7% reduction) when exposed to O₃ at a low concentration of 250 μg m⁻³ for 30 and 60 min. A significant negative relationship between the numbers of confirmed SARS-CoV-2 cases and ambient O₃ in Chinese cities indicated that the spread of SARS-CoV-2 may have been inhibited by high O₃. An analysis of data from Chongqing showed that the transmission of COVID-19 increased when the O₃ mixing ratios in the air were relatively low, and transmission decreased when O₃ increased. Based on these findings, we also propose a new Safety O₃ Emission (SOE) method to increase indoor O₃ to levels (&lt; 160 μg m⁻³) that inhibit the transmission of the SARS-CoV-2 but are not harmful for humans. This could serve as timely and low-cost solution for suppressing COVID-19 outbreaks throughout the world.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41810-021-00118-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50089239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overview and Seasonality of PM10 and PM2.5 in Guayaquil, Ecuador","authors":"Daniel Moran-Zuloaga,&nbsp;Wilson Merchan-Merchan,&nbsp;Emilio Rodríguez-Caballero,&nbsp;Philip Hernick,&nbsp;Julio Cáceres,&nbsp;Mauricio H. Cornejo","doi":"10.1007/s41810-021-00117-2","DOIUrl":"10.1007/s41810-021-00117-2","url":null,"abstract":"<div><p>The focus of this study is the assessment of total suspended particles (TSP) and particulate matter (PM) with various aerodynamic diameters in ambient air in Guayaquil, a city in Ecuador that features a tropical climate. The urban annual mean concentrations of TSP (Total Suspended Particles), and particle matter (PM) with various aerodynamic diameters such as: PM₁₀, PM_2.5 and PM₁ are 31 ± 14 µg m⁻³, 21 ± 9 µg m⁻³, 7 ± 2 µg m⁻³ and 1 ± 1 µg m⁻³, respectively. Air mass studies reveal that the city receives a clean Southern Ocean breeze. Backward trajectory analysis show differences between wet and dry seasons. During the dry season, most winds come from the south and southwest, while air masses from the peri urban may contribute as pollutant sources during the wet season. Although mean values of PM₁₀ and PM_2.5 were below dangerous levels, our year-round continuous monitoring study reveals that maximum values often surpassed those permissible limits allowed by the Ecuadorian norms. A cluster analysis shows four main paths in which west and southwest clusters account for more than 93% of the pollution. Total vertical column of NO₂ shows the pollution footprint is strongest during the dry season, as opposed to the wet season. A microscopic morphological characterization of ambient particles within the city during the wet and the dry season reveals coarse mode particles with irregular and rounded shapes. Particle analysis reveals that samples are composed of urban dust, anthropogenic and organic debris during the dry season while mainly urban dust during the wet season.</p></div>","PeriodicalId":36991,"journal":{"name":"Aerosol Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41810-021-00117-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50064660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}