Journal of Aerosol Science最新文献

{"title":"A direct and theoretically consistent method for the calculation of the settling speed of prolate spheroidal particles in the atmosphere","authors":"Sylvain Mailler ,&nbsp;Sotirios Mallios","doi":"10.1016/j.jaerosci.2025.106613","DOIUrl":"10.1016/j.jaerosci.2025.106613","url":null,"abstract":"<div><div>We propose a new method for calculating the settling speed of aerosol particles with prolate shape in the atmosphere. This method takes into account the known theoretical results on the speed–force relationships for prolate spheroids moving in a fluid, and the results in Mallios et al. (2021) regarding the orientation of prolate particles settling in the atmosphere. Unlike other studies, we focus not on the resistance problem (calculating the aerodynamic force as a function of speed) but on the mobility problem (calculate terminal velocity as a function of the external force). The result of this approach is a set of equations that permit to directly calculate the settling speed of a prolate particle in the atmosphere as a function of its shape and characteristics, which is a very important quantity in atmospheric science since the settling speed of a falling particle is a key factor to determine its lifetime in the atmosphere. With this approach, we show that the settling speed is reduced by up to 20% for particles with aspect ratio 4 compared to same-volume spheres. We compare the results of the present study to CFD results of Sanjeevi et al. (2022) and to laboratory measurements of Bhowmick et al. (2024), the latter comparison showing that the estimates for settling speed from our method is within <span><math><mrow><mo>±</mo><mn>5</mn><mtext>%</mtext></mrow></math></span> compared to the measured value. Finally, since calculating the terminal speed of settling particles is an important issue in atmospheric modeling, we provide a Fortran module implementing the method described in the present study.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106613"},"PeriodicalIF":3.9,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144469944","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":"Announcement of the 2024 Journal of Aerosol Science Excellence in Research Award Recipient","authors":"Chris Hogan (Editor-in-Chief, Journal of Aerosol Science)","doi":"10.1016/j.jaerosci.2025.106640","DOIUrl":"10.1016/j.jaerosci.2025.106640","url":null,"abstract":"","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106640"},"PeriodicalIF":3.9,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144469943","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":"Stochastic asymmetric bronchial tree models for population-scale variability in dosimetry","authors":"Debjit Kundu,&nbsp;Mahesh V. Panchagnula","doi":"10.1016/j.jaerosci.2025.106622","DOIUrl":"10.1016/j.jaerosci.2025.106622","url":null,"abstract":"<div><div>Pulmonary drug delivery has emerged as a preferred mode of drug administration due to its high effectiveness and reduced side effects compared to other methods. Drugs delivered in this manner can be classified into two classes. Some drugs target the lung tissue and are absorbed in the upper airways. Others aim to reach the deep lung, where they are absorbed into the bloodstream to produce systemic effects elsewhere in the body. The efficacy of drug delivery for both would depend on the regional deposition fraction. Various factors such as particle size, inhalation rate, etc. influence the deposition outcomes. More importantly, the trajectories of inhaled particles depend on the unique geometry of each person’s respiratory tract. Variation in lung anatomy is one of the main reasons why different people respond to inhaled medications differently. In addition, several diseases modify the geometry of the airways, leading to altered particle deposition patterns. Therefore, understanding and predicting regional deposition patterns of inhaled drugs becomes crucial for optimizing drug delivery strategies. To that end, we have developed a <em>stochastic asymmetric multi-path model</em> of the human airways. The tracheobronchial airways were generated based on Hess-Murray’s law and stochastic asymmetric branching. Symmetric and alveolated acinar sub-trees were attached to the terminal bronchioles. Through Monte-Carlo simulations, we report the extent, distribution and inter-subject variability in inhaled particle deposition as a function of several key parameters - <em>branching asymmetry, particle size, breathing rate and bronchoconstriction</em>. We show how particle size influences the deposition of particles, how asymmetry generally reduces deposition (barring certain exceptions) and how bronchoconstriction reduces deposition in the deep lung while increasing it in the upper airways. These insights will prove useful in determining drug dosages as well as design and choice of delivery devices such as inhalers and nebulizers.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106622"},"PeriodicalIF":3.9,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144469952","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":"Direct inversion for bidimensional distributions of aerosol characteristics","authors":"Timothy A. Sipkens,&nbsp;Joel C. Corbin","doi":"10.1016/j.jaerosci.2025.106636","DOIUrl":"10.1016/j.jaerosci.2025.106636","url":null,"abstract":"<div><div>Aerosol classifiers allow particle populations to be described in terms of mass, mobility diameter, or aerodynamic diameter distributions. When this classification is combined with a second layer of classification, a bidimensional distribution can be retrieved that provides additional insights into the distribution of aerosol properties. Bidimensional distributions are often transformed from extensive quantities related to the measurement (e.g., particle mass) to intensive ones that provide more intuitive insights of particle morphology (e.g., effective density or black-carbon mass fraction). Further, most extensive properties are highly correlated with one another (e.g., particle mass and mobility diameter). This complicates inversion, resulting in retrieved distributions that are considerably broader than the true distribution. In this work, we show that these problems can be solved using a single analysis step to compute distributions-of-interest, phrased in terms of intensive properties. This yields a <em>direct</em> inversion scheme that (1) avoids the need for post-processing to retrieve common distributions-of-interest; (2) reduces the correlation between the aerosol properties for which the bidimensional distribution is defined; (3) makes regularization easier and more objective; and (4) improves the minimum resolvable distribution width by up to 96 %. The approach is demonstrated using both simulated distributions (phantoms) and experimental data.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106636"},"PeriodicalIF":3.9,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144492167","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":"Investigation of the morphology and optical properties of graphene oxide for online diagnostics","authors":"Horace I. Looi ,&nbsp;Halil I. Yazici ,&nbsp;Joel C. Corbin ,&nbsp;Rym Mehri ,&nbsp;Timothy A. Sipkens ,&nbsp;Kyle J. Daun","doi":"10.1016/j.jaerosci.2025.106637","DOIUrl":"10.1016/j.jaerosci.2025.106637","url":null,"abstract":"<div><div>Graphene oxide (GO) particles have a wide and growing range of applications. They may also be converted to reduced graphene oxide (rGO) particles, which are increasingly used in energy storage devices like batteries and supercapacitors. However, the downstream functionality of GO and rGO particles depends strongly on their morphology, which is highly variable depending on the synthesis process. Here, we report morphological and optical properties for GO particles in the aerosol phase. These include the mobility diameter, effective density (0.93 ± 0.06 g/cm³), mass–mobility exponent (2.97 ± 0.06), Angstrom absorption exponent (2.48 between 370 nm and 950 nm), mass absorption cross-section (0.99 ± 0.22 m² g⁻¹), and mass scattering cross-section. Although this study reports measurements on re-aerosolized GO powder, the demonstrated techniques and measured properties serve as a foundation for in-reactor optical diagnostics that may allow for online control of the synthesis processes enabling the ability to control and characterize the functionality of downstream particles</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106637"},"PeriodicalIF":3.9,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144510885","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":"In-vitro visualization of aerosol deposition by laser-induced fluorescence in a human airway model","authors":"Stefanie Gürzing ,&nbsp;Anja Lena Thiebes ,&nbsp;Christian Gabriel Cornelissen ,&nbsp;Stefan Jockenhoevel ,&nbsp;Manuel Reddemann","doi":"10.1016/j.jaerosci.2025.106634","DOIUrl":"10.1016/j.jaerosci.2025.106634","url":null,"abstract":"<div><div>This study presents the first <em>in-vitro</em> visualization of aerosol deposition from the trachea up to the 10th bifurcation in a transparent airway model. The airway model simulates a representative respiratory tract of the left lower lobe and consists of all 23 generations of a human lung. Laser- induced fluorescence (LIF) was used to investigate the temporal and spatial deposition behavior of aerosols generated by a jet nebulizer along the representative airway. The <em>in-situ</em> measured LIF signal correlates to the amount of deposited aerosol during spontaneous breathing. By the means of LIF-image post-processing the temporal course of the LIF signal in each of the first eight bifurcations is correlated to the main aerosol deposition mechanisms, i.e. inertial impaction and gravitational settling, in the conductive airways. Depending on the time point in the respiratory cycle either one of both deposition mechanisms dominates the current aerosol deposition. The spatial analysis over eight subsequent bifurcations shows the diminishing influence of the inertial deposition mechanism over deeper bifurcations. Further, the duration of gravitational settling decreases over the bifurcations depending on the accompanying airway diameters of each bifurcation. The introduction of the dimensionless Froude number allows the comparison of the measured aerosol deposition to existing research and demonstrates that the proposed threshold limit in literature of Froude &lt;5 matches well to the gravitational settling regime observed in the transparent airway. For Froude &gt;5 mainly the inertial impaction is observed as mechanism for aerosol deposition in this set-up. An error analysis is performed for evaluating the influence of the low relative humidity of the inhaled air on the aerosol evaporation and deposition. This feasibility study shows the capability of the measurement method in combination with the airway model to resolve the aerosol deposition up to the eighth bifurcation. In future, this analysis should be extended to higher airway generations by microscopic LIF imaging to evaluate the deposition mechanisms in all 23 generations of the transparent airway model.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106634"},"PeriodicalIF":3.9,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144469942","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":"Parabolic flow tube reactor for tandem DMA studies of cluster ion evaporation kinetics: Design, theoretical data inversion, and preliminary results for ionic liquid nanodrops","authors":"J. Fernandez de la Mora,&nbsp;C. Luebbert,&nbsp;L.J. Perez-Lorenzo","doi":"10.1016/j.jaerosci.2025.106625","DOIUrl":"10.1016/j.jaerosci.2025.106625","url":null,"abstract":"<div><div>We seek to infer single-molecule evaporation rates from airborne ionic liquid clusters mobility-selected on a first DMA, flowing through a heated tube, with the ratio of product to parent fluxes determined on a second DMA. We connect theoretically the measured flux ratio to the reaction rate <em>k</em> via separation of variables, by assuming parabolic flow at large Peclet number (<em>Pe</em>). To minimize the non-parabolic entry flow region, we operate at moderate Reynolds numbers (∼150), resulting in a limited <em>Pe</em>. We identify practical conditions with small entry length and negligible finite-<em>Pe</em> corrections for the full (elliptic) non-reactive problem, which is numerically manageable despite the non-orthogonal eigenfunctions. We argue that moderate <em>Pe</em> corrections for the reactive problem are also small. The parent species problem is analogous to the nonreactive Graetz problem, though including the dimensionless first order reaction rate <em>K</em> as a free parameter. The product species problem involves an extra diffusivity ratio <em>γ</em> and non-standard functions, efficiently calculated by the computer program Mathematica. All other calculations involve diagonal matrices, enabling covering all the relevant range of dimensionless parameters: 1≤<em>K</em> ≤ 100; 1≤γ ≤ 1.4; arbitrary tube length <em>x</em>. These numerical results are condensed into tables for interpolations, enabling the quick inference of reaction constants from experimental data. The procedure is used to invert experimental data yielding the volatility of clusters of the ionic liquid EMI-FAP having diameters smaller than 3 nm. The approach is limited to situations where only one or two reaction products form.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106625"},"PeriodicalIF":3.9,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306255","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-frequency photothermal interferometry of single aerosol particles","authors":"Felix W. Stollberger ,&nbsp;Michael J. Gleichweit ,&nbsp;Ruth Signorell ,&nbsp;Alexander Bergmann","doi":"10.1016/j.jaerosci.2025.106621","DOIUrl":"10.1016/j.jaerosci.2025.106621","url":null,"abstract":"<div><div>The frequency dependence of photothermal and photoacoustic signals provides information on evaporation, condensation, and heat transfer processes in aerosol particles. Performing such measurements at the single particle level increases accuracy and provides access to various particle properties. Previously, this was not possible due to the resonant acoustic signal amplification required in photoacoustics, which restricted usable modulation frequencies to a single value. In this study, we introduce the use of multi-frequency photothermal interferometry (n<span><math><mi>ω</mi></math></span>-PTI) on single, optically trapped particles and experimentally investigate the frequency dependence of the photothermal signal. The observed signal and its dependence on the optical and thermophysical properties of the particle and the interferometer probe beam are analyzed by an accompanying theoretical model. Our measurements prove the applicability of the presented method and indicate a stronger frequency dependence of the photothermal amplitude from single particles than previously observed in bulk measurements. Furthermore, we were able to decouple the contributions from the particle temperature and the thermal wave propagation and examine their frequency dependencies individually. Finally, we analyzed the direct influence of the particle on the measured signal and showed the potential of frequency-resolved photothermal measurements to study thermophysical parameters or optical properties at the single particle level in the Knudsen transition regime.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106621"},"PeriodicalIF":3.9,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306253","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":"Dynamic of infectious aerosols generated by cough from patients with pulmonary tuberculosis","authors":"Taline Canto Tristão ,&nbsp;Mariana Abou Mourad Ferreira ,&nbsp;Pedro Sousa de Almeida Júnior ,&nbsp;Luiz Guilherme Schmidt Castellani ,&nbsp;Manuela Negrelli Brunetti ,&nbsp;Edward C. Jones-López ,&nbsp;Kevin P. Fennelly ,&nbsp;Michael R. Barer ,&nbsp;Carlos Henrique Fantecelle ,&nbsp;Saulo Almeida Morellato ,&nbsp;David Jamil Hadad ,&nbsp;Jerrold J. Ellner ,&nbsp;Reynaldo Dietze ,&nbsp;Moisés Palaci","doi":"10.1016/j.jaerosci.2025.106633","DOIUrl":"10.1016/j.jaerosci.2025.106633","url":null,"abstract":"<div><div>Tuberculosis (TB) is an ancient disease transmitted through aerosols frequently generated by coughing and it is still unknown whether there is variability in cough aerosol output throughout the day and whether this may impact patients’ infectivity categorization. To study the dynamic of infectious aerosols generated by cough, we conducted a cross-sectional study on pulmonary TB patients (n = 16) who had their cough-generated aerosols sampled twice daily for two consecutive days for the Cough Aerosol Sampling System (CASS) assay. Most patients were classified as Variable Low Producers and Variable High Producers (n = 10; 62.5 %), followed by Negative Producers (n = 4; 25 %) and Consistent Producers (n = 2; 12.5 %). Additionally, most recovered bacilli (88.7 %) within a respiratory aerosol size range. Although the time of collection did not appear to impact on aerosol infectivity, performing CASS with multiple samples allowed for more accurate detection and distinction among aerosol producers.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106633"},"PeriodicalIF":3.9,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144280573","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":"Concurrent supersaturation of C2-C4 alcohols and water in a Condensation Particle Counter (CPC) to measure naturally charged flame-formed carbonaceous aerosols smaller than 3 nm","authors":"Farnaz Khosravi ,&nbsp;Gregory S. Lewis ,&nbsp;Arantzazu Eiguren Fernandez ,&nbsp;Francesco Carbone","doi":"10.1016/j.jaerosci.2025.106626","DOIUrl":"10.1016/j.jaerosci.2025.106626","url":null,"abstract":"<div><div>Combustion emissions impact air pollution, and the development of advanced tools to detect and monitor increasingly smaller flame-formed aerosols is vital for implementing ever-more effective air-quality regulations and reducing the environmental impact of combustion applications. Condensation Particle Counters (CPCs) can detect both charged and neutral aerosols in very low number concentrations and are of widespread use in atmospheric metrology thanks to their relative portability, affordability, and simplicity of operation. Still, their detection efficiency is influenced by the size, charge state, and morphology of the aerosols to be detected, in addition to their composition, which influences their wettability by the condensing fluid(s). As a result, calibrations are necessary to characterize the detection efficiency of a CPC, especially for flame-formed carbonaceous aerosols smaller than 3 nm, which can have quite polydisperse composition and properties. In this study, two-component (<em>fluid</em>-Water) CPCs resulting from coupling a Water CPC (WCPC) with a <em>saturator</em> inlet operated with either n-butanol (nBA), iso-propanol (IPA), or ethanol (EtOH) are characterized for the detection of naturally charged carbonaceous aerosols formed in an incipiently sooting premixed flame. Khosravi et al. (2023) operated the <em>saturator</em> inlet with Diethylene Glycol (DEG) and showed that the concurrent supersaturations of water and DEG (i.e., any <em>fluid</em> with <em>Le</em> &gt; 1) established in the DEG-WCPC (i.e., any <em>fluid</em>-WCPC) enhance the detection of materials smaller than 3 nm. The results herein demonstrate that the nBA-WCPC, the IPA-WCPC, and the EtOH-WCP have not only comparable or even superior (surely in the case of the IPA-WCPC) performances in terms of the minimum sizes detectable with 50 % efficiency but also the advantages of minimal needs for cleaning the optics and composition-independent and steeper profiles of the size-dependent detection efficiency compared to the DEG-WCPC. This is the case even though the lengths of the CPC stages have not been optimized yet for using the tested C2-C4 alcohols in the <em>saturator</em> inlet. In particular, the use of EtOH as a performant CPC working fluid is the first-of-a-kind, with the EtOH-WCPC already achieving the steepest detection efficiency profiles, a feature attractive for studies requiring sizing resolution, and having the largest room for performance improvements.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106626"},"PeriodicalIF":3.9,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144330601","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}