Journal of Aerosol Science最新文献

{"title":"Optimizing dry powder inhaler for laryngopharyngeal reflux: Effects of particle size and breathing technique","authors":"Shamudra Dey ,&nbsp;Aditya Jadcherla ,&nbsp;Nikki Johnston ,&nbsp;Jonathan M. Bock ,&nbsp;Guilherme J.M. Garcia","doi":"10.1016/j.jaerosci.2025.106641","DOIUrl":"10.1016/j.jaerosci.2025.106641","url":null,"abstract":"<div><div>Dry powder inhalers (DPIs) were designed to treat lung diseases, but are now being repurposed to address laryngopharyngeal reflux, a condition with no effective treatment. This study assessed how particle size and breathing technique affect DPI deposition on the laryngopharynx using computational fluid dynamics (CFD). Time-dependent airflow and particle transport simulations were performed using the <span><math><mrow><mi>k</mi><mo>−</mo><mi>ω</mi></mrow></math></span> turbulence model on a 3-dimensional airway model of a healthy adult. Regional doses were estimated for sinusoidal breathing profiles with different durations (short vs. long inhalation) and depths (shallow vs. forceful inhalation). Three DPIs were simulated assuming log-normal particle size distributions with mass median aerodynamic diameters <span><math><mrow><mo>(</mo><msub><mi>d</mi><mn>50</mn></msub><mo>)</mo></mrow></math></span> of 3 μm (DPI-1), 10 μm (DPI-2), or 50 μm (DPI-3) representing commercially available DPIs (DPI-1 and DPI-3) and a theoretical DPI optimized for laryngopharyngeal deposition (DPI-2). Particle size was the dominant factor with laryngopharyngeal doses of 5.3%, 20.3%, and 2.2% of the emitted dose for DPI-1, DPI-2, and DPI-3, respectively, with a normal inhalation (30L/min, 2s inhalation). Inhalation duration had a negligible impact on laryngopharyngeal dose for DPI-1 (short inhalation: 6.2%, long inhalation: 4.9%), DPI-2 (short inhalation: 20.6%, long inhalation: 20.3%) and DPI-3 (short inhalation: 1.9%, long inhalation: 2.3%). Similarly, inhalation depth had a negligible impact on the laryngopharyngeal dose for DPI-1 (shallow inhalation: 5.3%, medium inhalation: 5.8%, forceful inhalation: 6.5%), DPI-2 (shallow inhalation: 20.3%, medium inhalation: 20.0%, forceful inhalation: 21.4%) and DPI-3 (shallow inhalation: 2.2%, medium inhalation: 2.0%, forceful inhalation: 2.2%). In summary, our simulations suggest that particle size affects the laryngopharyngeal dose more significantly than the breathing technique with a mass median aerodynamic diameter of <span><math><mrow><msub><mi>d</mi><mn>50</mn></msub><mo>=</mo><mn>10</mn><mo>μ</mo><mi>m</mi></mrow></math></span> being predicted to maximize drug delivery to the laryngopharynx. Further studies are needed to validate these findings in larger cohorts.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106641"},"PeriodicalIF":3.9,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517876","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":"Performance investigation of machine learning for optical modeling of black carbon aerosols with different coatings and humidities","authors":"Donghui Zhou ,&nbsp;Jia Liu ,&nbsp;Jinbao Han ,&nbsp;Jianfei Luo ,&nbsp;Bo Yin","doi":"10.1016/j.jaerosci.2025.106639","DOIUrl":"10.1016/j.jaerosci.2025.106639","url":null,"abstract":"<div><div>Optical properties of black carbon (BC) aerosols are essential for assessing atmospheric radiation and climate change, but fast and accurate optical calculation for BC with complex structures is still a challenge. In this study, a quick optical modeling method for BC coated by different materials under various humidities is developed based on the multiple-sphere <em>T</em>-matrix (MSTM) simulation and support-vector-machine (SVM) algorithm. The typical closed-cell, coated-aggregate, and partially-coated BC models with BC monomers ranging from 50 to 2000 and BC volume fractions ranging from 0.05 to 0.70 are employed, and the relative errors (REs) and determination coefficients (R²) are used to investigate the prediction performance of optical properties based on SVM. Results show that the SVM predicted optical properties, such as optical efficiency, asymmetry factor, single scattering albedo, and lidar ratio, overall agree well with the properties simulated using MSTM. The prediction performance could be influenced by coating structure and morphological parameters, most of the values of REs and R² were smaller than about 20 % and larger than about 0.85, respectively. The relative humidities (RHs) and coating materials slightly deteriorate the performance of SVM. With RHs increasing from 0 % to 95 %, or the coatings become non-absorbing organic carbon (OC) and brown carbon (BrC), the largest REs increase to over 30 %, while most of the R² is still larger than 0.85. This study presented a promising optical modeling method for BC aerosols, and it could be further improved with the development of machine learning.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"189 ","pages":"Article 106639"},"PeriodicalIF":3.9,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144364563","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":"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}