ACS ES&T Air最新文献

{"title":"","authors":"Rachel O’Brien*, Hongmin Yu, Natalie Warren, Claire Robinson, Christopher Y. Lim, Carolyn E. Jordan, Bruce E. Anderson, Jesse H. Kroll and Christopher D. Cappa, ","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 5","pages":"XXX-XXX XXX-XXX"},"PeriodicalIF":0.0,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acsestair.4c00270","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144452535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"Jie Zhang*, Tianyu Zhu, Qi Zhang, Nga L. Ng, Alexandra Catena, Margaret J. Schwab, Jorge Gonzalez-Cruz, Shan Zhou, Jianzhong Xu, Julia Stuart, Amanda Teora, Dirk Felton and James J. Schwab, ","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 5","pages":"XXX-XXX XXX-XXX"},"PeriodicalIF":0.0,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acsestair.4c00260","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144452536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating Aerial Data Preanalysis Schemes and Site-Level Methane Emission Aggregation Methods at Liquefied Natural Gas Facilities","authors":"Olga Khaliukova*,&nbsp;Yuanrui Zhu,&nbsp;William S. Daniels,&nbsp;Arvind P. Ravikumar,&nbsp;Gregory B. Ross,&nbsp;Selina A. Roman-White,&nbsp;Fiji C. George and Dorit M. Hammerling,&nbsp;","doi":"10.1021/acsestair.4c0030110.1021/acsestair.4c00301","DOIUrl":"https://doi.org/10.1021/acsestair.4c00301https://doi.org/10.1021/acsestair.4c00301","url":null,"abstract":"<p >Methane observations at liquefied natural gas (LNG) facilities play an important role in characterizing methane emissions from the natural gas supply chain. The large size and complexity of LNG facilities make quantifying emissions with ground-based monitoring systems challenging, making aerial platforms one of the preferred methods for detecting and estimating methane emissions at these sites. However, aerial measurements typically provide a snapshot of emissions at a given instance, necessitating further analytical steps to infer both annualized emissions and the range of possible emissions at different instances in time. This study uses aerial measurements at two U.S. LNG facilities from a Quantification, Monitoring, Reporting, and Verification project to characterize the distribution of temporally averaged emissions (i.e., annualized inventories) and possible site-level emissions at any given point in time (“instantaneous emissions”). The former provides uncertainty on the aerial measurement component of measurement-informed annual inventories, while the latter helps contextualize future snapshot measurements, such as those from aerial surveys or high-resolution satellite platforms, at LNG facilities. We find that instantaneous emissions may fall well outside of the distribution describing uncertainty in the annual inventory. We also compare different preanalysis schemes for aerial data, as existing literature does not provide a clear consensus on methods for doing so, especially at LNG facilities. We find the persistence assumption to be the most critical preanalysis factor.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 6","pages":"1009–1019 1009–1019"},"PeriodicalIF":0.0,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Uptake of Exogenous Volatile Organic Compounds Enhances the NO2-to-HONO Conversion on Soot","authors":"Xinyuan Zhao,&nbsp;Qiang Wang*,&nbsp;Peng Zhang*,&nbsp;Yonghong Wang*,&nbsp;Shuying Li,&nbsp;Zhanyu Su,&nbsp;Jun Liu,&nbsp;Biwu Chu,&nbsp;Qingxin Ma,&nbsp;Yujing Mu and Hong He,&nbsp;","doi":"10.1021/acsestair.5c0007210.1021/acsestair.5c00072","DOIUrl":"https://doi.org/10.1021/acsestair.5c00072https://doi.org/10.1021/acsestair.5c00072","url":null,"abstract":"<p >Heterogeneous reduction of nitrogen dioxides (NO₂) on soot has been suggested to be a source of nitrous oxide (HONO) in the atmosphere. However, conventional wisdom says that the contribution of NO₂ reduction on soot to HONO formation is limited due to the rapid deactivation of surface reductive sites in the atmosphere. On the contrary, we show that adsorbed anthropogenic and biogenic volatile organic compounds (VOCs), collectively called exogenous VOCs (EVOCs), can persistently promote the heterogeneous conversion of NO₂ to HONO on soot. The surface uptake of NO₂ driven by H₂O, coupled with the hydrogen reduction of NO₂ supported by EVOCs on elemental carbon (EC), is proposed to be the key pathway causing the persistent production of HONO. Furthermore, field observation conducted during biomass burning seasons in the North China Plain also showed that the presence of EVOCs promotes HONO production significantly. Our results imply that the continuous adsorption and conversion of EVOCs on soot surfaces may have a remarkable enhancing impact on the persistent conversion of NO₂ to HONO in the atmosphere.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 6","pages":"1107–1114 1107–1114"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct Observation of Liquid–Liquid Phase Separation and Core–Shell Morphology of PM2.5 Collected from Three Northeast Asian Cities and Implications for N2O5 Hydrolysis","authors":"Mijung Song*,&nbsp;Ying Li,&nbsp;Changjoon Seong,&nbsp;Hang Yang,&nbsp;Kyoung-Soon Jang,&nbsp;Zhijun Wu,&nbsp;Ji Yi Lee,&nbsp;Atsushi Matsuki and Joonyoung Ahn,&nbsp;","doi":"10.1021/acsestair.5c0004310.1021/acsestair.5c00043","DOIUrl":"https://doi.org/10.1021/acsestair.5c00043https://doi.org/10.1021/acsestair.5c00043","url":null,"abstract":"<p >The morphologies of aerosol particles significantly influence atmospheric processes, including heterogeneous chemistry. This study presents direct observations of liquid–liquid phase separation and the morphologies of PM_2.5 filter extracts collected from Seoul, Beijing, and Noto during autumn 2023. The PM_2.5 samples covered both polluted and clean environments and were predominantly organic-rich. Optical microscopy revealed that real-world samples from these cities underwent phase transitions with changing relative humidity and primarily existed in either two-liquid or three-phase states, while fully homogeneous or nonliquid states were rare. Moreover, a core–shell morphology, consisting of an organic shell and inorganic core, was frequently observed in the PM_2.5 samples. Calculations confirmed that the viscosity of the organic shell ranges from ∼10¹ Pa s in Seoul (liquid-like) to ∼10⁶ Pa s in Beijing (semisolid). As the shell becomes more viscous, the diffusivity of N₂O₅ decreases, thereby lowering the N₂O₅ uptake coefficient by 1–3 orders of magnitude and significantly restricting N₂O₅ uptake. These results highlight the crucial role of aerosol morphology in heterogeneous chemistry, as the organic-rich outer phase can significantly modify the reactive uptake coefficients and gas–particle interactions.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 6","pages":"1079–1088 1079–1088"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential Errors in CMAQ NO:NO2 Ratios and Upper Tropospheric NO2 Impacting the Interpretation of TROPOMI Retrievals","authors":"Abiola S. Lawal,&nbsp;T. Nash Skipper,&nbsp;Cesunica E. Ivey,&nbsp;Daniel L. Goldberg,&nbsp;Jennifer Kaiser and Armistead G. Russell*,&nbsp;","doi":"10.1021/acsestair.4c0019810.1021/acsestair.4c00198","DOIUrl":"https://doi.org/10.1021/acsestair.4c00198https://doi.org/10.1021/acsestair.4c00198","url":null,"abstract":"<p >Although Chemical Transport Models (CTMs) such as the Community Multiscale Air Quality Model (CMAQ) have been used in linking observations of trace gases to emissions and developing vertical column distributions, there remain consistent biases between CTM simulations and satellite retrievals. Simulated tropospheric NO₂ vertical column densities (VCDs) are generally higher over areas with large NO_<i>x</i> sources when compared with retrievals, while an opposite bias is found over low NO_<i>x</i> regions. Artificial (i.e., numerical) dilution in the model, where emissions are mathematically dispersed uniformly within the originating CTM grid, can impact modeled NO:NO₂ ratios, while lower CTM VCD levels often observed over rural areas can be attributed to missing emission sources of NO_<i>x</i> or flawed horizontal/vertical transport. Potential causes of both low and high biases are assessed in this study using CMAQ and Tropospheric Monitoring Instrument (TROPOMI) NO₂ retrievals. It was found that more detailed modeling of NO_<i>x</i> plumes to assess the NO:NO₂ ratio in two power plant plumes can mitigate the effect of artificial computational dilution, reducing the bias and overall differences in the observed vs modeled plumes (errors reduced by 30%). Adjustments of upper tropospheric NO₂ led to overall improvements, with a reduction in CMAQ bias (−43% to −29%) and improved spatial correlation (0.81 to 0.86). This study highlights the importance of having accurate modeled NO:NO₂ ratios when comparing models to retrievals and the impact of unintentional numerical dilution.</p><p >Underestimates of upper tropospheric NO₂ coupled with artificial mixing of NO_<i>x</i> emissions in chemical transport models can lead to low and high biases in simulated NO₂ vertical column densities when compared to satellite retrievals.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 6","pages":"998–1008 998–1008"},"PeriodicalIF":0.0,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsestair.4c00198","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential Errors in CMAQ NO:NO₂ Ratios and Upper Tropospheric NO₂ Impacting the Interpretation of TROPOMI Retrievals.","authors":"Abiola S Lawal, T Nash Skipper, Cesunica E Ivey, Daniel L Goldberg, Jennifer Kaiser, Armistead G Russell","doi":"10.1021/acsestair.4c00198","DOIUrl":"10.1021/acsestair.4c00198","url":null,"abstract":"<p><p>Although Chemical Transport Models (CTMs) such as the Community Multiscale Air Quality Model (CMAQ) have been used in linking observations of trace gases to emissions and developing vertical column distributions, there remain consistent biases between CTM simulations and satellite retrievals. Simulated tropospheric NO₂ vertical column densities (VCDs) are generally higher over areas with large NO _<i>x</i> sources when compared with retrievals, while an opposite bias is found over low NO _<i>x</i> regions. Artificial (i.e., numerical) dilution in the model, where emissions are mathematically dispersed uniformly within the originating CTM grid, can impact modeled NO:NO₂ ratios, while lower CTM VCD levels often observed over rural areas can be attributed to missing emission sources of NO _<i>x</i> or flawed horizontal/vertical transport. Potential causes of both low and high biases are assessed in this study using CMAQ and Tropospheric Monitoring Instrument (TROPOMI) NO₂ retrievals. It was found that more detailed modeling of NO _<i>x</i> plumes to assess the NO:NO₂ ratio in two power plant plumes can mitigate the effect of artificial computational dilution, reducing the bias and overall differences in the observed vs modeled plumes (errors reduced by 30%). Adjustments of upper tropospheric NO₂ led to overall improvements, with a reduction in CMAQ bias (-43% to -29%) and improved spatial correlation (0.81 to 0.86). This study highlights the importance of having accurate modeled NO:NO₂ ratios when comparing models to retrievals and the impact of unintentional numerical dilution.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 6","pages":"998-1008"},"PeriodicalIF":0.0,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12172011/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144328326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Germicidal UV Air Disinfection Devices on Indoor Air Quality in an Unoccupied Aged Care Facility","authors":"Emily Barnes Franklin*,&nbsp;Amanda Wheeler,&nbsp;Jason Ward,&nbsp;Caleb Mynard,&nbsp;Dylan Lynton,&nbsp;Ruhi Humphries,&nbsp;James Harnwell,&nbsp;Vinay Menon,&nbsp;Jason Monty,&nbsp;Michelle Delaire,&nbsp;Suman Majumdar,&nbsp;Simon Joosten,&nbsp;Lidia Morawska and Erin Dunne*,&nbsp;","doi":"10.1021/acsestair.4c0032210.1021/acsestair.4c00322","DOIUrl":"https://doi.org/10.1021/acsestair.4c00322https://doi.org/10.1021/acsestair.4c00322","url":null,"abstract":"<p >The COVID-19 pandemic has precipitated renewed interest in germicidal ultraviolet (GUV) for indoor air disinfection. However, UV-C radiation from these devices can produce indoor air pollutants including ozone, oxygenated volatile organic compounds (OVOCs), and ultrafine particles. A month-long study of indoor air quality effects of GUV was undertaken in an unoccupied aged care facility in Melbourne, Australia under both mechanical ventilation (∼3 air changes h^–1) and natural ventilation (∼1 h^–1) conditions. Upper room GUV-254 and whole room GUV-222 devices were tested. GUV-222 produced ∼670 μg/h of ozone resulting in &lt;1 ppb enhancements in indoor ozone. GUV-222 also produced small increases in OVOCs, particularly acetic acid and methanol, that were &lt;1 ppb with mechanical ventilation, and &lt;2 ppb with natural ventilation. Small acetaldehyde enhancements (∼0.1 ppb) were associated with GUV-254. GUV was not associated with changes in indoor particles. GUV-222 and -254 initiated OVOC enhancements were insensitive to indoor ozone but exhibited strong temperature and humidity sensitivities, suggesting UV-initiated surface chemistry rather than gas phase chemistry as the key driver of GUV OVOC enhancements. Overall, ventilation and changes in outdoor pollutants had substantial effects, while GUV produced small but measurable effects on indoor air quality in a real-world urban setting.</p><p >Germicidal UV indoor air cleaners are an airborne pathogen spread mitigation option but can produce air pollutants. GUV produced small but measurable effects on indoor air quality, largely driven by surface chemistry, when deployed an unoccupied aged care facility.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 6","pages":"1042–1054 1042–1054"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsestair.4c00322","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gaseous and Particulate Emissions from a Small Business Jet Using Conventional Jet A-1 and a 30% SAF Blend","authors":"Lukas Durdina*,&nbsp;Zachary C. J. Decker,&nbsp;Jacinta Edebeli,&nbsp;Curdin Spirig,&nbsp;Tobias Frischknecht,&nbsp;Julien G. Anet,&nbsp;Benjamin T. Brem,&nbsp;Frithjof Siegerist and Theo Rindlisbacher,&nbsp;","doi":"10.1021/acsestair.5c0005310.1021/acsestair.5c00053","DOIUrl":"https://doi.org/10.1021/acsestair.5c00053https://doi.org/10.1021/acsestair.5c00053","url":null,"abstract":"<p >Small turbofan engines (&lt;26.7 kN thrust) are unregulated for gaseous and particulate emissions, with emissions data largely absent from public databases. Yet, their environmental impact is likely increasing. This study examines emissions from a representative small turbofan engine on a Cessna Citation 560XL. It focuses on nonvolatile particulate matter (nvPM), gaseous pollutants, and volatile organic compounds (VOCs). Ground-level measurements were conducted using a standardized system with conventional Jet A-1 and a 30% blend of synthesized paraffinic kerosene from hydroprocessed esters and fatty acids (HEFA-SPK). This sustainable aviation fuel (SAF) blend reduced the nvPM mass and number emission indices (EIs) by ∼35% and ∼20% at idle, with diminishing effects at higher thrust. Estimated nvPM number EIs at cruise decreased by ∼10%, suggesting a similar reduction in contrail ice particle concentrations at the predicted nvPM number EIs. While CO, HC, and NO_<i>x</i> emissions remained unchanged, SO₂ emissions decreased proportionally to the fuel sulfur content. VOC analysis showed lower emissions of complex unsaturated hydrocarbons. These findings highlight SAF’s potential to mitigate climate and air quality impacts. They also reveal discrepancies in estimated emissions from small turbofan engines and underscore limitations in existing models that predict fuel composition effects on nvPM emissions.</p><p >This study reports gaseous and nonvolatile particulate emissions of a popular small jet aircraft fueled with fossil Jet A-1 and a 30% biofuel blend. The findings highlight the potential of sustainable aviation fuels to reduce harmful emissions and inform future predictive models for small, unregulated turbofan engines.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 5","pages":"967–978 967–978"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsestair.5c00053","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143921388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioaerosol Emission Characteristics from Laboratory Burns","authors":"Abu Sayeed Md Shawon,&nbsp;Alejandro Gutierrez and Katherine B. Benedict*,&nbsp;","doi":"10.1021/acsestair.4c0031010.1021/acsestair.4c00310","DOIUrl":"https://doi.org/10.1021/acsestair.4c00310https://doi.org/10.1021/acsestair.4c00310","url":null,"abstract":"<p >Combustion processes can aerosolize and transport particles both from nonbiological and biological origin, with the latter termed bioaerosol particle (BAP). Previous work has shown an increase in the level of BAP in smoke plumes. The mechanism of their emission, whether from combustion of biological material or coemission with dust and soil from fire-driven winds, has yet to be examined. We carried out a series of controlled combustion experiments to understand the role of vegetation type and combustion conditions in the direct emission of BAP. The fuels we used included broadleaf, evergreen, and grass. We measured the emitted fluorescent BAP using a wideband integrated bioaerosol system (WIBS), and we measured the viability of filter-collected BAP using flow cytometry. Our measurements showed that the size and absolute concentration of the fluorescent BAP, and the viability of the BAP emitted during combustion, depend on the combustion conditions. In addition, the type of fuel impacted the type of emitted fluorescent BAP fraction relative to the total concentration of the emitted aerosol.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 5","pages":"857–867 857–867"},"PeriodicalIF":0.0,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143921187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}