Journal of Aerosol Science最新文献

{"title":"Machine learning algorithm facilitates fast derivation of light-scattering properties of sea salt aerosol","authors":"Quan Lin ,&nbsp;Bingqi Yi ,&nbsp;Lei Bi ,&nbsp;Zhiyong Yang","doi":"10.1016/j.jaerosci.2025.106571","DOIUrl":"10.1016/j.jaerosci.2025.106571","url":null,"abstract":"<div><div>Accounting for the impacts of ambient relative humidity (RH) on the optical properties of sea salt aerosols usually requires complex and time-consuming light-scattering computations. To facilitate the process, this study employs machine learning algorithms to gain fast access to the single-scattering properties (including extinction efficiency, scattering efficiency, single-scattering albedo, and asymmetry factor) of sea salt aerosols at arbitrary particle sizes, RHs and wavelengths. The sea salt particles are modeled as either coated-spheres or homogeneous spheres depending on the ambient relative humidity, and their scattering properties are calculated using the invariant imbedding T-matrix method at selected sizes, wavelengths, and RHs to establish a data set for the training and validation purposes. Extensive tests using various machine learning methods and hyperparameter optimizations are implemented. It is demonstrated that the Gradient Boosting Decision Trees method optimized with Optuna tuning outperforms the other methods in predicting the scattering properties of sea salt aerosols. The developed model is promising for radiative transfer applications involving sea salt aerosols and similar approach could be potentially applied to the other scenarios where quick access to the aerosol optical properties is desirable.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"187 ","pages":"Article 106571"},"PeriodicalIF":3.9,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Dispersion of particles and airflow optimization for a semiconductor cleanroom","authors":"Chunli Tang ,&nbsp;Tianchi Liang ,&nbsp;Kambiz Vafai","doi":"10.1016/j.jaerosci.2025.106570","DOIUrl":"10.1016/j.jaerosci.2025.106570","url":null,"abstract":"<div><div>Electronic cleanrooms' airflow and particle behavior significantly impact product quality and energy consumption. The airflow and particle diffusion at different supply air velocities are calculated for a semiconductor cleanroom, well-validated against established data. An RNG k-ε model and discrete phase model (DPM) are employed to simulate airflow and particle transport. Transient distributions, residual counts, and removal times are compared for six air supply velocities ranging from 0.2 m/s to 0.12 m/s. The results indicate that vortices are easily generated in the corners formed by the walls and the ceiling edge. The local vortices result in a longer particle removal time. Under stable conditions, all particles released from the ceiling, walls 1, 2, 4, and the raised floor are removed from the cleanroom across six supply air velocities. Two particles released from wall 3 remain as residuals when the supply air velocity is reduced. The final residual particles are primarily located near equipment 6. When the supply air velocity decreases from 0.22 m/s to 0.16 m/s, the stable time remains at 14 min. However, it increases significantly to 17 min and 23 min at 0.14 m/s and 0.12 m/s, respectively. The addition of two Fan Filter Units (FFUs) in the corners of the ceiling enhances both airflow and particle diffusion, reducing removal times by 2–7 min across different air speeds. These results provide theoretical guidance for selecting supply air velocity and optimized the arrangement of FFUs and equipment.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106570"},"PeriodicalIF":3.9,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Comparative analysis of Eulerian and Lagrangian models for the simulation of fine and ultrafine particle dynamics in the wake of a heavy truck","authors":"Mokhtar Djeddou ,&nbsp;Aude Pérard-Lecomte ,&nbsp;Georges Fokoua ,&nbsp;Amine Mehel ,&nbsp;Anne Tanière","doi":"10.1016/j.jaerosci.2025.106568","DOIUrl":"10.1016/j.jaerosci.2025.106568","url":null,"abstract":"<div><div>Predicting the turbulent dispersion of particulate pollutants is essential for understanding and mitigating the environmental impact of road traffic emissions, particularly those from heavy vehicles. This study examines the behavior of low-inertia particles in the turbulent wake of a heavy truck, a region dominated by complex and inhomogeneous airflow that significantly influences pollutant dynamics. Numerical simulations were performed based on the RANS-SST <span><math><mrow><mi>k</mi><mi>ω</mi></mrow></math></span> model for carrier-phase flow characterization, and three different approaches were applied to model the dispersed phase, namely the Lagrangian eddy interaction model (EIM), the Eulerian diffusion-inertia model (DIM) and a scalar advection–diffusion equation. To assess the accuracy of these numerical models, experimental measurements were carried out in an open-circuit wind tunnel. Particle image velocimetry (PIV) was used to characterize airflow, while a low-pressure electric impactor (ELPI) measured particle concentrations.</div><div>While numerical simulations generally aligned with experimental data, the Lagrangian EIM model overestimated particle concentrations at the wake vortex periphery, highlighting some limitations in capturing particle-turbulence interactions in highly anisotropic and inhomogeneous flows. Conversely, the Eulerian DIM and scalar advection–diffusion models proved closer to the experimental results, reasonably reproducing low-inertia particle dispersion, where inertial effects were found to be negligible. These results underline the importance of selecting an appropriate combination of turbulence and particle models to simulate the dispersion of particulate pollutants, providing valuable information for improving forecasts of traffic-related pollution and its environmental and health impacts.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106568"},"PeriodicalIF":3.9,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"The fate of selected electronic nicotine delivery systems (ENDS) constituents in adolescents and young adults","authors":"Bahman Asgharian ,&nbsp;Owen Price ,&nbsp;Jeffry Schroeter ,&nbsp;Cissy Li ,&nbsp;Ryan M. Haskins ,&nbsp;Susan Chemerynski","doi":"10.1016/j.jaerosci.2025.106569","DOIUrl":"10.1016/j.jaerosci.2025.106569","url":null,"abstract":"<div><div>Electronic nicotine delivery systems (ENDS) use is prevalent among adolescents and young adults. While there have been several efforts to estimate the exposure and dose of ENDS puff constituents in adults, no study to date has focused on younger ENDS users. Given the non-uniformity of lung growth with age, the lungs of young people cannot be considered miniature versions of those of adults; in addition, breathing profiles and flow rates may substantially differ with age. Thus, inhalation dosimetry models developed for adults cannot be directly applied to youth without proper modifications. We extended a previously developed ENDS aerosol deposition model for adults to younger ages (10–21 years) by developing age-specific lung geometries based on available data on lung morphometry and using relationships such as the volume of the oral cavity of adults based on the relevant trachea dimensions, using relationships for volume of the oral cavity for inhaled puff volume, and functional residual capacity (FRC) at different ages. We then used the age-specific deposition model to predict the fate of an ENDS puff with selected constituents (nicotine, propylene glycol, vegetable glycerin, benzaldehyde, and vanillin). Model predictions showed similar patterns of deposition to those of adults in terms of droplet deposition versus vapor uptake. Total deposition and deposition per surface area of individual constituents in the lung decreased with age. The age-specific deposition model is a useful tool to predict lung deposition of ENDS aerosol constituents and compare results across different age groups.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106569"},"PeriodicalIF":3.9,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"The collision kernel of nanoparticles in homogeneous isotropic turbulence: Direct simulations and modelling","authors":"Maximilian Karsch,&nbsp;Andreas Kronenburg","doi":"10.1016/j.jaerosci.2025.106552","DOIUrl":"10.1016/j.jaerosci.2025.106552","url":null,"abstract":"<div><div>An accurate model for the collision kernel is essential to predict the growth dynamics of agglomerates in both, natural and industrial processes. In many cases, including the gas-phase synthesis of functional nanoparticles in flames, the model development is hampered by the coupled effects of turbulent shear and Brownian diffusion on the relative particle motion. In the present work, we perform detailed numerical simulations of spherical Brownian particles in homogeneous isotropic turbulence where their individual trajectories are directly resolved. In this way, particle pair statistics such as relative velocities, clustering profiles and, most importantly, the geometric collision rate are deduced for mono- and bidisperse systems.</div><div>Our results show that Brownian diffusion inhibits particle clustering by distributing particles more uniformly, resulting in an effective reduction of the radial distribution function. This behaviour is also observed in bidisperse particle populations where the reduction is shown to be controlled by the harmonic mean of both Peclet numbers. In addition, mean radial relative velocities are significantly enhanced when Brownian motion is considered and this increase is most evident at low Stokes and Peclet numbers. We further develop a semi-empirical model to predict the binary collision kernel by fitting suitable expressions to the simulation data. Lastly, an <em>a posteriori</em> analysis is carried out to demonstrate the model’s accuracy by comparing the results of the population balance calculations against independent simulations of coalescing particles. Using the present model, the error in the predicted particle number density could be reduced to around 23% while existing models from the literature deviate from the detailed simulation by a factor of 2.1 and more.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106552"},"PeriodicalIF":3.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143619976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Bipolar coagulation in bipolar electrosprays: Optimizing coagulation efficiency and hetero-agglomerate composition","authors":"Matthias Kawalek,&nbsp;Wolfgang Peukert,&nbsp;Christian Lübbert","doi":"10.1016/j.jaerosci.2025.106557","DOIUrl":"10.1016/j.jaerosci.2025.106557","url":null,"abstract":"<div><div>This work investigates the bipolar coagulation of oppositely charged nanoparticles, a few nanometers in size, generated by a bipolar electrospray. These particles form after highly charged droplets produced by the electrospray evaporate, carrying a fraction of the initial droplet charge. The particle charge fraction depends on the non-volatile volume fraction of the feed solution. However, during evaporation, ions and charged clusters form that carry the remaining droplet charge, competing with particle-particle coagulation and thus reducing coagulation efficiency. To enhance coagulation efficiency, the non-volatile volume fraction of the feed solution was increased by adding diethylene glycol (DEG). Additionally, the number of salt particles in the agglomerates was tuned by changing the conductivity ratio of the feed solutions. Experiments were conducted using glucose and sodium chloride particles as a model system for material based applications. Notably, glucose evaporates completely from the coagulated particles, making this system suitable for our tandem DMA setup with a tube furnace between the two DMAs. This setup allowed us to obtain 2D distributions containing information on agglomerate concentration and composition and to optimize coagulation efficiency.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106557"},"PeriodicalIF":3.9,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Multi-objective Bayesian optimization for the retrieval of aggregated aerosol structures from microscopic images","authors":"Abhishek Singh,&nbsp;Smruti Ranjan Jena,&nbsp;Abhishek Gupta,&nbsp;Thaseem Thajudeen","doi":"10.1016/j.jaerosci.2025.106556","DOIUrl":"10.1016/j.jaerosci.2025.106556","url":null,"abstract":"<div><div>Aerosol particles are increasingly recognized for their significant impacts on human health and climate. Often found in aggregated form, the morphology of these particles plays a crucial role in influencing their physicochemical properties. Owing to the sub-micron size, electron microscopy is the most commonly used technique to visualize the aggregated particles. In a prior study, we proposed a combination of forward modelling coupled with optimization techniques for the prediction of 3-dimensional structures from microscopic images. Here, we extend the methodology to a multi-objective optimization approach for the specific cases where aggregated particles are classified and sampled based on specific properties such as mobility diameter, aerodynamic diameter etc. The comparison of 2-dimensional features of the microscopic image with the projections of computationally generated aggregates forms the first objective function, while the comparison of the measured 3-dimensional property, mobility diameter, is used as the second objective function. The estimation of the mobility diameter often requires the calculation of the hydrodynamic radius (R_h) and the orientationally averaged projected area (PA), which can be computationally expensive for larger aggregates and for frequent calculations. Bayesian optimization is used for the retrieval process, as it can provide much faster convergence with significantly fewer function evaluations compared to metaheuristic algorithms. The multi-objective Bayesian optimization-based retrieval algorithm has been validated using synthetically generated and experimentally collected microscopic images. The process is found to be about 5–10 times faster than previously reported methods. The algorithm is further extended to retrieve aggregates with polydisperse and overlapping monomers. The retrieval process demonstrated strong accuracy, with fractal parameters showing around 10–15% error compared to the original values. This includes a mobility diameter difference of less than 10%, indicating high similarity between retrieved and input structures. Furthermore, tests are conducted on welding fume particles of varying mobility diameters, where retrieved structures consistently exhibited mobility diameters within a 10% difference from original values.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106556"},"PeriodicalIF":3.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"ToF-SIMS analyses of brake wear particles in human epithelial Caco-2 cells","authors":"Robin Rydbergh ,&nbsp;Lisa-Marie Witte ,&nbsp;Jonas Sjöblom ,&nbsp;Nathalie Scheers ,&nbsp;Amir Saeid Mohammadi ,&nbsp;Eric Voortman Landström ,&nbsp;Tore V. Vernersson ,&nbsp;Per Malmberg","doi":"10.1016/j.jaerosci.2025.106553","DOIUrl":"10.1016/j.jaerosci.2025.106553","url":null,"abstract":"<div><div>Air pollutants, especially fine particulate matter (diameter of &lt;2.5 μm), are associated with severe health risks including increased cardiopulmonary and lung cancer mortality and development of neurodegenerative diseases. This study introduces a novel methodology that begins with <em>in situ</em> particulate pollution collection, proceeds to exposing non-animal human epithelial cell models which are then analyzed through high spatial resolution mass spectrometry imaging to differentiate the chemistry of particles among exposed cells. During regular train operations, brake wear particles (BWP) are primarily generated from brake pad abrasion. For this work, a custom train brake rig was used to generate BWP, which were then introduced to human epithelial Caco-2 cells. First, the BWP size distributions were characterized using an Electrical Low-Pressure Impactor and particles ranging from 1.1 to 2.7 μm were collected with a gravimetric impactor. A suspension of these BWP, characterized by Dynamic Light Scattering, was added to Caco-2 cells cultured on coverslips. After incubation, the cells were washed and fixed by freeze-drying to preserve the epithelial structure. Subsequent analyses with SEM and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) established substantial, partially agglomerated, BWP deposits on the surface of the epithelial cellular structures. Further analysis of the ToF-SIMS data using Multivariate Curve Resolution-Alternating Least Squares, achieved a better separation of underlying chemical distributions. This enhanced image contrast facilitated the observation of particle-cell interactions. The results demonstrate the efficacy and potential of ToF-SIMS mass spectrometry imaging in distinguishing and potentially characterizing particle-cell interactions. This methodology may be further refined by incorporating complementary analytical techniques such as ICP-MS to better quantify metal content in particles and attempts with smaller particles might help assess cellular particle penetration and accumulation.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106553"},"PeriodicalIF":3.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143563692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Indoor air sampling for detection of viral nucleic acids","authors":"Lennart J. Justen ,&nbsp;Simon L. Grimm ,&nbsp;Kevin M. Esvelt ,&nbsp;William J. Bradshaw","doi":"10.1016/j.jaerosci.2025.106549","DOIUrl":"10.1016/j.jaerosci.2025.106549","url":null,"abstract":"<div><div>Detecting and monitoring airborne viruses is critical for mitigating the spread of infectious diseases and safeguarding public health. Indoor air sampling has emerged as a promising but underexplored approach to the surveillance of viral pathogens, complementing more established methods such as clinical diagnostics and wastewater-based epidemiology. Indoor air contains viral particles originating from human occupants through exhaled respiratory droplets, skin shedding, and resuspension of contaminated dust, making it a valuable target for viral biosurveillance. Although viruses typically account for less than 1% of total sequences in metagenomic data from air samples, a wide range of human-infecting viruses, including respiratory and skin-associated pathogens, can be detected using various capture mechanisms. This review provides a comprehensive examination of indoor air sampling for viral nucleic acid detection, focusing on the sources and composition of viruses indoors; sampling technologies; and strategies for effective implementation. We examine three complementary approaches to viral collection: active air sampling using dedicated collection devices; passive sampling primarily through settled dust analysis; and monitoring of building heating, ventilation, and air conditioning (HVAC) systems. For active sampling, we assess previously published results on the efficacy of filtration, impaction, impingement, cyclonic separation, electrostatic precipitation, and condensation for viral collection, highlighting challenges in optimizing sampling efficiency for submicrometer particles and recovering sufficient viral nucleic acids for analysis. For passive and HVAC-based approaches, we evaluate their potential for providing temporally-integrated, building-wide viral surveillance data while requiring minimal additional infrastructure. We examine potential strategies for implementing these approaches, particularly in airports and healthcare facilities. Future studies should focus on addressing such knowledge gaps, optimizing sampling methodologies, and developing best practices for integrating air sampling into public health surveillance systems.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"187 ","pages":"Article 106549"},"PeriodicalIF":3.9,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Condensational growth of spherical water droplets altered under external electric fields","authors":"D.N. Gabyshev","doi":"10.1016/j.jaerosci.2025.106554","DOIUrl":"10.1016/j.jaerosci.2025.106554","url":null,"abstract":"<div><div>The article explores the theoretical aspects of the growth of small water droplets by condensation in significant electric fields, commonly present in cumulonimbus and thunderstorm clouds. The research investigates the impact of exposure to electric fields on growth using a comprehensive thermodynamic approach, which incorporates various sources of the field, such as the cloud’s field, electrokinetic potential within the diffuse layer, droplet’s charge and polarisation. The model considers the anisotropy of field superposition and demonstrates analytical integration techniques across the droplet’s surface. Overall, the study expands our understanding of electric-field-driven droplet growth and corroborates prior findings of enhanced condensation.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"186 ","pages":"Article 106554"},"PeriodicalIF":3.9,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143563691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}