Journal of Aerosol Science最新文献_第3页

Carrier gas-driven compositional variations of platinum-tungsten nanoparticles generated by spark ablation

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-20 DOI: 10.1016/j.jaerosci.2025.106538

Nina Zábojníková , Viliam Vretenár , Ján Híveš , Tomáš Němec

Bimetallic nanoparticles are of interest in various catalytic applications as cost-effective replacements for precious metal catalysts. Ongoing research is aimed at developing new techniques to produce nanoparticles with precise control of their composition, size, and structure. In this study, we investigated the tuning of the composition of platinum–tungsten bimetallic nanoparticles by spark ablation. Using pure electrodes, the spark ablation method offers the possibility of forming mixed nanoparticles and adjusting their size and composition by modifying the carrier gas mixture. Morphological, structural, and compositional characterizations by High-Angle Annular Dark-Field (HAADF) and Bright Field (BF) imaging in Scanning Transmission Electron Microscopy (STEM) and Energy Dispersive X-ray (EDX) microanalysis were used to evaluate the nanoparticle size distribution and the ratio of Pt to W, whereas interlayer d-spacings were quantified using the Selected Area Electron Diffraction (SAED) technique. Similar to previous studies that have demonstrated homogeneous internal nanoparticle mixing with different electrodes, we observed that the nanoparticles generated from the monometallic electrodes were mixed mostly homogeneously. Additionally, we demonstrate that the use of platinum as the initial anode and tungsten as the initial cathode in a nitrogen atmosphere can promote the formation of core-shell nanostructures. A theoretical model of electrode ablation was developed using the current and voltage discharge profiles to estimate the composition of the synthesized nanoparticles. The modeling revealed a longer period between platinum electrode evaporation and tungsten electrode evaporation during spark discharges as a potential reason for core-shell formation.

{"title":"Carrier gas-driven compositional variations of platinum-tungsten nanoparticles generated by spark ablation","authors":"Nina Zábojníková , Viliam Vretenár , Ján Híveš , Tomáš Němec","doi":"10.1016/j.jaerosci.2025.106538","DOIUrl":"10.1016/j.jaerosci.2025.106538","url":null,"abstract":"<div><div>Bimetallic nanoparticles are of interest in various catalytic applications as cost-effective replacements for precious metal catalysts. Ongoing research is aimed at developing new techniques to produce nanoparticles with precise control of their composition, size, and structure. In this study, we investigated the tuning of the composition of platinum–tungsten bimetallic nanoparticles by spark ablation. Using pure electrodes, the spark ablation method offers the possibility of forming mixed nanoparticles and adjusting their size and composition by modifying the carrier gas mixture. Morphological, structural, and compositional characterizations by High-Angle Annular Dark-Field (HAADF) and Bright Field (BF) imaging in Scanning Transmission Electron Microscopy (STEM) and Energy Dispersive X-ray (EDX) microanalysis were used to evaluate the nanoparticle size distribution and the ratio of Pt to W, whereas interlayer d-spacings were quantified using the Selected Area Electron Diffraction (SAED) technique. Similar to previous studies that have demonstrated homogeneous internal nanoparticle mixing with different electrodes, we observed that the nanoparticles generated from the monometallic electrodes were mixed mostly homogeneously. Additionally, we demonstrate that the use of platinum as the initial anode and tungsten as the initial cathode in a nitrogen atmosphere can promote the formation of core-shell nanostructures. A theoretical model of electrode ablation was developed using the current and voltage discharge profiles to estimate the composition of the synthesized nanoparticles. The modeling revealed a longer period between platinum electrode evaporation and tungsten electrode evaporation during spark discharges as a potential reason for core-shell formation.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106538"},"PeriodicalIF":3.9,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101789","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}

引用次数: 0

Effect of concentration and sizes of solid particles in slurry droplets on their collision behavior in gas

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-19 DOI: 10.1016/j.jaerosci.2025.106537

A.G. Islamova, P.P. Tkachenko, P.A. Strizhak

Experimental research findings are reported on the effect of concentrations and sizes of particles, as well as the sizes of initial droplets containing these particles, on the characteristics of their collisions in gas. Droplets of liquid containing bituminous coal particles with a size of 60–120 μm and MS-VP-A9 glass microspheres with a size of 20–120 μm were utilized. The particle concentration ranged from 0.01% to 1%. The patterns of collisions of low-concentration slurry droplets have been recorded. Four collision regimes of droplets have been distinguished: bounce, coalescence, separation and disruption. The characteristics of secondary liquid fragments (child droplets) have been determined. Conditions of coalescence, bounce, separation and disruption of slurry droplets, as well as their secondary atomization for subsequent intensification of physicochemical processes have been defined. Guidelines have been provided for using the research findings in industrial applications with variable Weber numbers and impact angles.

引用次数: 0

Investigation and simulation of droplet breakup and iron oxide nanoparticle formation in spray-flame synthesis

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-18 DOI: 10.1016/j.jaerosci.2025.106535

Ivan Skenderović, Frank Einar Kruis

Particle formation from an iron-based precursor dissolved in ethanol and 2-ethylhexanoic acid was studied via population balance simulations of the SpraySyn burner. Monte-Carlo population balance modeling was used to estimate droplet evaporation and breakup, while particle nucleation and growth were calculated using a pivot method. To investigate common particle formation pathways a precursor chemistry model was formulated and discussed for the cases of instantaneous and absent thermal decomposition in the liquid phase. Following this, the droplet breakup time was calculated to determine when precursor and particle transfer into the gas phase occurs. The simulation results show good agreement with experimental data from literature for different precursor concentrations. However, in the cases where thermal decomposition is absent in the liquid phase, the model underestimates particle size and polydispersity. The primary conclusion is that nanoparticles smaller than 10 nm most likely formed in the liquid phase. Moreover, particle formation in the liquid phase increases polydispersity through the formation of an accumulation mode near the droplet surface.

{"title":"Investigation and simulation of droplet breakup and iron oxide nanoparticle formation in spray-flame synthesis","authors":"Ivan Skenderović, Frank Einar Kruis","doi":"10.1016/j.jaerosci.2025.106535","DOIUrl":"10.1016/j.jaerosci.2025.106535","url":null,"abstract":"<div><div>Particle formation from an iron-based precursor dissolved in ethanol and 2-ethylhexanoic acid was studied via population balance simulations of the SpraySyn burner. Monte-Carlo population balance modeling was used to estimate droplet evaporation and breakup, while particle nucleation and growth were calculated using a pivot method. To investigate common particle formation pathways a precursor chemistry model was formulated and discussed for the cases of instantaneous and absent thermal decomposition in the liquid phase. Following this, the droplet breakup time was calculated to determine when precursor and particle transfer into the gas phase occurs. The simulation results show good agreement with experimental data from literature for different precursor concentrations. However, in the cases where thermal decomposition is absent in the liquid phase, the model underestimates particle size and polydispersity. The primary conclusion is that nanoparticles smaller than 10 nm most likely formed in the liquid phase. Moreover, particle formation in the liquid phase increases polydispersity through the formation of an accumulation mode near the droplet surface.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106535"},"PeriodicalIF":3.9,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101791","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}

引用次数: 0

Atmospheric implications of fumaric acid - Water binary clusters

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-18 DOI: 10.1016/j.jaerosci.2025.106524

Neba Lovette Ambe , Olivier Holtomo , Ayiseh Frederick Tandong , David Afungchui

Fumaric acid (FA) is amongst the most abundant low molecular-weight dicarboxylic acids in the atmosphere and is present in atmospheric aerosols. However, the climate implications of fumaric acid in the presence of water (W) are not yet known. In the present study, the structures and thermodynamics of the most stable isomers of FA(H₂O)_n (n = 1–10) are investigated using APF-D/6-311+G(d, p) and benchmarked with ωB97X-D/6–311++G(3df,3pd). The atmospheric abundance and IR spectra of these complexes are calculated alongside the use of the narrow-band model (NBM) to estimate the radiative forcing efficiencies (RE) of hydrates. Optical properties such as Rayleigh light scattering intensities for natural and polarized light were then calculated. The clusters FA(H₂O)_n are held together by strong hydrogen bonds formed between the water molecules and the carboxylic acid functional group. The binding free energies of the most stable clusters of n = 1–5 are negative and decrease with cluster size while for n = 6–10, they are positive. Cluster concentration decreases with relative humidity (RH) with the smaller clusters dominating at all investigated RH. These clusters show high evaporation rates at 298K and 1atm. Also, the radiative forcing efficiencies of FA(H₂O)_n = 1-10 are positive and increase with cluster size. This major part of the radiative forcing occurs within the atmospheric window region 250–1500 cm⁻¹. Analysis of the Rayleigh scattering properties showed that the Rayleigh scattering intensity is enhanced upon the increase of the number of water molecules in the cluster. Therefore in the atmosphere, FA(H₂O)_n = 1-10 induces a scattering which reduces its overall heating effect on the earth.

{"title":"Atmospheric implications of fumaric acid - Water binary clusters","authors":"Neba Lovette Ambe , Olivier Holtomo , Ayiseh Frederick Tandong , David Afungchui","doi":"10.1016/j.jaerosci.2025.106524","DOIUrl":"10.1016/j.jaerosci.2025.106524","url":null,"abstract":"<div><div>Fumaric acid (FA) is amongst the most abundant low molecular-weight dicarboxylic acids in the atmosphere and is present in atmospheric aerosols. However, the climate implications of fumaric acid in the presence of water (W) are not yet known. In the present study, the structures and thermodynamics of the most stable isomers of FA(H<sub>2</sub>O)<sub>n</sub> (n = 1–10) are investigated using APF-D/6-311+G(d, p) and benchmarked with ωB97X-D/6–311++G(3df,3pd). The atmospheric abundance and IR spectra of these complexes are calculated alongside the use of the narrow-band model (NBM) to estimate the radiative forcing efficiencies (RE) of hydrates. Optical properties such as Rayleigh light scattering intensities for natural and polarized light were then calculated. The clusters FA(H<sub>2</sub>O)<sub>n</sub> are held together by strong hydrogen bonds formed between the water molecules and the carboxylic acid functional group. The binding free energies of the most stable clusters of n = 1–5 are negative and decrease with cluster size while for n = 6–10, they are positive. Cluster concentration decreases with relative humidity (RH) with the smaller clusters dominating at all investigated RH. These clusters show high evaporation rates at 298K and 1atm. Also, the radiative forcing efficiencies of FA(H<sub>2</sub>O)<sub>n = 1-10</sub> are positive and increase with cluster size. This major part of the radiative forcing occurs within the atmospheric window region 250–1500 cm<sup>−1</sup>. Analysis of the Rayleigh scattering properties showed that the Rayleigh scattering intensity is enhanced upon the increase of the number of water molecules in the cluster. Therefore in the atmosphere, FA(H<sub>2</sub>O)<sub>n = 1-10</sub> induces a scattering which reduces its overall heating effect on the earth.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106524"},"PeriodicalIF":3.9,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101792","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}

引用次数: 0

Optimized reconstruction of adhesion force distribution from resuspension measurements using the Rock’n’Roll model

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-17 DOI: 10.1016/j.jaerosci.2025.106539

R. Almog , D. Ben Shlomo , S. Sevilia , S. Elisha , I. Salame , B. Parizer , K. Szajna , D. Wrana , F. Krok , E. Fattal , V. Babin , Z. Klausner , R. Berkovich

Resuspension, a widely studied phenomenon for decades due to its environmental, industrial, and health impacts, is gaining renewed interest, especially for inhalable particles (smaller than 10 μm) posing health risks. Models describing particle resuspension from surfaces evaluate the fraction of resuspended particles by using their adhesion distribution as input. However, measuring adhesion in the microscale can be a challenging and expensive task, as it requires special skills and instrumentation, such as Atomic Force Microscopy. In this study, we suggest an inverse-by-optimization approach to estimate the adhesion distributions from a measured resuspension curve as an optimization process. Our algorithm utilizes the widely used Rock'n’Roll (RnR) resuspension model to calculate numerical resuspension curves from adhesion distributions. The calculated resuspension curves are compared to a measured resuspension curve based on their degree of agreement, as indicated by the Root Mean Squared Error (RMSE) statistic. The optimization process aims to find a theoretical curve that provides a minimal RMSE value. The parameters that yield the best fit determine the optimal adhesion distribution that represents the particles' interaction with the surface. We evaluated our algorithm using the dataset from Reeks and Hall (2001), which enabled us to accurately assess the adhesion distribution they had employed. Then the algorithm was used to estimate the adhesion distribution from resuspension measurements that we conducted for this study. These were performed in a specially designed wind duct where 8 μm diameter glass colloids of were resuspended from a glass surface. The application of this algorithm to our measured resuspension curves resulted in an adhesion distribution with a median adhesion force value of ∼1400 nN. This value lies within the range of reported measurements of adhesion between glass colloidal spheres and glass surface.

{"title":"Optimized reconstruction of adhesion force distribution from resuspension measurements using the Rock’n’Roll model","authors":"R. Almog , D. Ben Shlomo , S. Sevilia , S. Elisha , I. Salame , B. Parizer , K. Szajna , D. Wrana , F. Krok , E. Fattal , V. Babin , Z. Klausner , R. Berkovich","doi":"10.1016/j.jaerosci.2025.106539","DOIUrl":"10.1016/j.jaerosci.2025.106539","url":null,"abstract":"<div><div>Resuspension, a widely studied phenomenon for decades due to its environmental, industrial, and health impacts, is gaining renewed interest, especially for inhalable particles (smaller than 10 μm) posing health risks. Models describing particle resuspension from surfaces evaluate the fraction of resuspended particles by using their adhesion distribution as input. However, measuring adhesion in the microscale can be a challenging and expensive task, as it requires special skills and instrumentation, such as Atomic Force Microscopy. In this study, we suggest an inverse-by-optimization approach to estimate the adhesion distributions from a measured resuspension curve as an optimization process. Our algorithm utilizes the widely used Rock'n’Roll (RnR) resuspension model to calculate numerical resuspension curves from adhesion distributions. The calculated resuspension curves are compared to a measured resuspension curve based on their degree of agreement, as indicated by the Root Mean Squared Error (<em>RMSE</em>) statistic. The optimization process aims to find a theoretical curve that provides a minimal <em>RMSE</em> value. The parameters that yield the best fit determine the optimal adhesion distribution that represents the particles' interaction with the surface. We evaluated our algorithm using the dataset from Reeks and Hall (2001), which enabled us to accurately assess the adhesion distribution they had employed. Then the algorithm was used to estimate the adhesion distribution from resuspension measurements that we conducted for this study. These were performed in a specially designed wind duct where 8 μm diameter glass colloids of were resuspended from a glass surface. The application of this algorithm to our measured resuspension curves resulted in an adhesion distribution with a median adhesion force value of ∼1400 nN. This value lies within the range of reported measurements of adhesion between glass colloidal spheres and glass surface.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106539"},"PeriodicalIF":3.9,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101786","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}

引用次数: 0

Transfer function and transmission measurements of the Perez differential mobility analyzer (DMA) at moderate sheath flow rates

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-17 DOI: 10.1016/j.jaerosci.2025.106534

Yiliang Liu , Michel Attoui , Sebastian Holm , Arttu Yli-Kujala , Runlong Cai , Yang Chen , Juha Kangasluoma

The newly developed Perez Differential Mobility Analyzer (DMA) provides high size resolution for viral particles and similarly sized particles. In this study, we measured its transfer function and transmission at moderate sheath flow rates (from 20 to 100 L min⁻¹) to extend its application for the measurement of broader sized particles. Two DMAs—a Perez Fat DMA and a Perez Thin DMA, were first calibrated using tetraheptylammonium bromide monomer (THA⁺) at sheath flow rates ranging from 100 to 400 L min⁻¹. Subsequently, a tandem Perez DMA setup was constructed. The former DMA was operated at high sheath/aerosol flow rate ratios to classify metal particles sized between 10 and 30 nm with a high resolution. The latter DMA was operated at moderate sheath flow rates ranging from 20 to 100 L min⁻¹. Particles classified by the former DMA were assumed monodispersed and used to calibrate the latter one. The measured transfer function for 10 nm particles was only slightly broader than the theoretical transfer function, with broadening factors of f_σ = 1.39 for the Perez Thin DMA and 1.28 for the Perez Fat DMA. The Perez Thin DMA exhibited higher resolutions than the Perez Fat DMA. For 20 nm particles, the Perez Thin DMA achieved a size resolution exceeding 8 at a sheath/aerosol flow rate ratio of 20/2 and over 11 when the ratio increased to 100/5. The penetration efficiencies of 10–30 nm particles were higher than 72.6%, with the Perez Fat DMA having higher penetration efficiencies than the Perez Thin DMA. Decreasing penetration efficiencies were observed under higher sheath flow rates, likely due to minor flow turbulence and changes in the electric field at the DMA outlet, which contributed to particle losses. After calibration, the Perez Fat DMA was adapted to measure the size distributions and charging properties of metal particles produced in a wire generator. At moderate sheath flow rates, Perez DMAs provide an extended size measurement range, high size resolution, and excellent penetration efficiency.

{"title":"Transfer function and transmission measurements of the Perez differential mobility analyzer (DMA) at moderate sheath flow rates","authors":"Yiliang Liu , Michel Attoui , Sebastian Holm , Arttu Yli-Kujala , Runlong Cai , Yang Chen , Juha Kangasluoma","doi":"10.1016/j.jaerosci.2025.106534","DOIUrl":"10.1016/j.jaerosci.2025.106534","url":null,"abstract":"<div><div>The newly developed Perez Differential Mobility Analyzer (DMA) provides high size resolution for viral particles and similarly sized particles. In this study, we measured its transfer function and transmission at moderate sheath flow rates (from 20 to 100 L min<sup>−1</sup>) to extend its application for the measurement of broader sized particles. Two DMAs—a Perez Fat DMA and a Perez Thin DMA, were first calibrated using tetraheptylammonium bromide monomer (THA⁺) at sheath flow rates ranging from 100 to 400 L min⁻<sup>1</sup>. Subsequently, a tandem Perez DMA setup was constructed. The former DMA was operated at high sheath/aerosol flow rate ratios to classify metal particles sized between 10 and 30 nm with a high resolution. The latter DMA was operated at moderate sheath flow rates ranging from 20 to 100 L min⁻<sup>1</sup>. Particles classified by the former DMA were assumed monodispersed and used to calibrate the latter one. The measured transfer function for 10 nm particles was only slightly broader than the theoretical transfer function, with broadening factors of <em>f</em><sub><em>σ</em></sub> = 1.39 for the Perez Thin DMA and 1.28 for the Perez Fat DMA. The Perez Thin DMA exhibited higher resolutions than the Perez Fat DMA. For 20 nm particles, the Perez Thin DMA achieved a size resolution exceeding 8 at a sheath/aerosol flow rate ratio of 20/2 and over 11 when the ratio increased to 100/5. The penetration efficiencies of 10–30 nm particles were higher than 72.6%, with the Perez Fat DMA having higher penetration efficiencies than the Perez Thin DMA. Decreasing penetration efficiencies were observed under higher sheath flow rates, likely due to minor flow turbulence and changes in the electric field at the DMA outlet, which contributed to particle losses. After calibration, the Perez Fat DMA was adapted to measure the size distributions and charging properties of metal particles produced in a wire generator. At moderate sheath flow rates, Perez DMAs provide an extended size measurement range, high size resolution, and excellent penetration efficiency.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106534"},"PeriodicalIF":3.9,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101794","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}

引用次数: 0

Dimensional analysis for jet diameter prediction in electrospray: Integrating electric field and process parameters

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-17 DOI: 10.1016/j.jaerosci.2025.106540

Jorge A. Estrada-Díaz, Ingrid B. Aguilar-Meza, Daniel Olvera-Trejo, Alex Elías-Zúñiga, Oscar Martínez-Romero

In electrospray, understanding the formation of the Taylor cone and liquid jet is required for predicting the droplet size during liquid breakup. Existing models have not assessed the effect of the electric field and its interaction with process parameters and material properties, which is particularly relevant when needle-electrode experimental setups vary. This study proposes a mathematical model and experimentally validates the prediction of jet diameter through dimensional analysis, clarifying the strong relationship between dependent and independent dimensionless groups, and observing interactions among process parameters such as wetting diameter, flow, and electric field, reflecting the effects of applied voltage and needle-electrode arrangement, as well as material properties such as surface tension, electrical conductivity, dielectric constant, and viscosity. The derived mathematical expression for jet diameter prediction demonstrated an average error of 5% when tested with ethylene glycol, effectively addressing the influence of electric field and process parameters on the proposed scaling laws.

{"title":"Dimensional analysis for jet diameter prediction in electrospray: Integrating electric field and process parameters","authors":"Jorge A. Estrada-Díaz, Ingrid B. Aguilar-Meza, Daniel Olvera-Trejo, Alex Elías-Zúñiga, Oscar Martínez-Romero","doi":"10.1016/j.jaerosci.2025.106540","DOIUrl":"10.1016/j.jaerosci.2025.106540","url":null,"abstract":"<div><div>In electrospray, understanding the formation of the Taylor cone and liquid jet is required for predicting the droplet size during liquid breakup. Existing models have not assessed the effect of the electric field and its interaction with process parameters and material properties, which is particularly relevant when needle-electrode experimental setups vary. This study proposes a mathematical model and experimentally validates the prediction of jet diameter through dimensional analysis, clarifying the strong relationship between dependent and independent dimensionless groups, and observing interactions among process parameters such as wetting diameter, flow, and electric field, reflecting the effects of applied voltage and needle-electrode arrangement, as well as material properties such as surface tension, electrical conductivity, dielectric constant, and viscosity. The derived mathematical expression for jet diameter prediction demonstrated an average error of 5% when tested with ethylene glycol, effectively addressing the influence of electric field and process parameters on the proposed scaling laws.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106540"},"PeriodicalIF":3.9,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101788","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}

引用次数: 0

Kinetic model of heterogeneous growth onto organic particles in supersaturated water environments

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-16 DOI: 10.1016/j.jaerosci.2025.106541

Xin Wang, Qi Zhang, Tong Zhang, Shoujie Yan, Lin Liu, Luying Yang

Submicrometer organic particulate matter (PM2.5) is a significant pollutant in industrial environments that poses a severe threat to the product quality and physical wellbeing of production personnel. Water vapor phase transition is a particle growth mechanism through the nucleation of organic particles by a supersaturated steam field and the formation of droplet embryos in the active part of the particle surface, which promotes the growth of organic particles and reduces the suspended concentration of organic particles in the plant environment. This study establishes a kinetic model for the heterogeneous nucleation of submicrometer organic matter particles under water vapor conditions. Considering the particle surface roughness, condensation mechanism, and three-phase line long-force correction, the model introduces a correction of the orientation force of the droplet embryo on the surface of the organic particles. Using polyalphaolefin as a representative organic particle, this study investigated the influence of condensation mechanisms on the radius of droplet embryos, the effect of the saturation ratio on the radius of the droplet embryo, and variations in the nucleation barrier and nucleation rate. The results indicate that the kinetic model of organic particulate matter modified with orientation force exhibits a higher rate of liquid droplet embryo formation than conventional particle kinetic models. Furthermore, as the saturation ratio increases, the critical nucleation free energy decreases, rendering the nucleation barrier easier to overcome. A negative correlation exists between the nucleation rate and nucleation barrier, with an optimal value for the saturation ratio.

{"title":"Kinetic model of heterogeneous growth onto organic particles in supersaturated water environments","authors":"Xin Wang, Qi Zhang, Tong Zhang, Shoujie Yan, Lin Liu, Luying Yang","doi":"10.1016/j.jaerosci.2025.106541","DOIUrl":"10.1016/j.jaerosci.2025.106541","url":null,"abstract":"<div><div>Submicrometer organic particulate matter (PM2.5) is a significant pollutant in industrial environments that poses a severe threat to the product quality and physical wellbeing of production personnel. Water vapor phase transition is a particle growth mechanism through the nucleation of organic particles by a supersaturated steam field and the formation of droplet embryos in the active part of the particle surface, which promotes the growth of organic particles and reduces the suspended concentration of organic particles in the plant environment. This study establishes a kinetic model for the heterogeneous nucleation of submicrometer organic matter particles under water vapor conditions. Considering the particle surface roughness, condensation mechanism, and three-phase line long-force correction, the model introduces a correction of the orientation force of the droplet embryo on the surface of the organic particles. Using polyalphaolefin as a representative organic particle, this study investigated the influence of condensation mechanisms on the radius of droplet embryos, the effect of the saturation ratio on the radius of the droplet embryo, and variations in the nucleation barrier and nucleation rate. The results indicate that the kinetic model of organic particulate matter modified with orientation force exhibits a higher rate of liquid droplet embryo formation than conventional particle kinetic models. Furthermore, as the saturation ratio increases, the critical nucleation free energy decreases, rendering the nucleation barrier easier to overcome. A negative correlation exists between the nucleation rate and nucleation barrier, with an optimal value for the saturation ratio.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106541"},"PeriodicalIF":3.9,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102225","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}

引用次数: 0

Mechanical properties of bare and coated soot aggregates probed by atomic force microscopy

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2025-01-03 DOI: 10.1016/j.jaerosci.2024.106523

Ashoka Karunarathne , Egor V. Demidov , Ali Hasani , Alexei F. Khalizov

Soot from incomplete combustion of carbonaceous materials is a major constituent of atmospheric aerosols. Individual soot particles are aggregates of primary carbon spherules connected together by carbon necks. Freshly released soot aggregates have lacey fractal morphology, but in the atmosphere they undergo compaction, induced by capillary forces exerted by liquid coatings that act against the covalent, cohesive and friction forces between the carbon spherules. Since compaction alters the optical properties and atmospheric lifetime of soot, an ability to model this process is important for predicting the soot’s environmental impacts. To inform and validate our recently developed discrete element method (DEM) model of a soot aggregate, we employed force spectroscopy by atomic force microscopy to measure the forces and other mechanical properties related to the bonding between the spherules in the individual soot aggregates. Fractal and compact aggregates, both bare and with liquid coatings were examined. We observed a characteristic sawtooth pattern on force–displacement curves and collected statistics on bonding forces within individual fractal aggregates, as they were fractured and unraveled. Contrary to fractal aggregates, compact aggregates could not be unraveled due to multiple cohesive interactions between spherules. An increase in bonding forces and energies due to capillarity was observed in coated aggregates. The sawtooth pattern was interpreted with the help of a simple conceptual model and the rigorous DEM model was used to show that only one or two necks need to be fractured for a fractal aggregate to yield, and that mechanical failure will most likely be in shear.

{"title":"Mechanical properties of bare and coated soot aggregates probed by atomic force microscopy","authors":"Ashoka Karunarathne , Egor V. Demidov , Ali Hasani , Alexei F. Khalizov","doi":"10.1016/j.jaerosci.2024.106523","DOIUrl":"10.1016/j.jaerosci.2024.106523","url":null,"abstract":"<div><div>Soot from incomplete combustion of carbonaceous materials is a major constituent of atmospheric aerosols. Individual soot particles are aggregates of primary carbon spherules connected together by carbon necks. Freshly released soot aggregates have lacey fractal morphology, but in the atmosphere they undergo compaction, induced by capillary forces exerted by liquid coatings that act against the covalent, cohesive and friction forces between the carbon spherules. Since compaction alters the optical properties and atmospheric lifetime of soot, an ability to model this process is important for predicting the soot’s environmental impacts. To inform and validate our recently developed discrete element method (DEM) model of a soot aggregate, we employed force spectroscopy by atomic force microscopy to measure the forces and other mechanical properties related to the bonding between the spherules in the individual soot aggregates. Fractal and compact aggregates, both bare and with liquid coatings were examined. We observed a characteristic sawtooth pattern on force–displacement curves and collected statistics on bonding forces within individual fractal aggregates, as they were fractured and unraveled. Contrary to fractal aggregates, compact aggregates could not be unraveled due to multiple cohesive interactions between spherules. An increase in bonding forces and energies due to capillarity was observed in coated aggregates. The sawtooth pattern was interpreted with the help of a simple conceptual model and the rigorous DEM model was used to show that only one or two necks need to be fractured for a fractal aggregate to yield, and that mechanical failure will most likely be in shear.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106523"},"PeriodicalIF":3.9,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102219","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}

引用次数: 0

A high performance differential mobility analyzer for the masses

IF 3.9 3区环境科学与生态学 Q2 ENGINEERING, CHEMICAL

Journal of Aerosol Science

Pub Date : 2024-12-30 DOI: 10.1016/j.jaerosci.2024.106522

Juan Fernandez de la Mora , Jerzy Kozlovski

A hand-held Differential Mobility Analyzer (DMA) weighting 4 kg is developed to operate laminarly at many hundreds of L/min, while covering at unusually high resolution the 1–200 nm size range. Coupled with a small and efficient portable vacuum cleaner pump requiring no cooling, a resolving power of 10 or more is obtained at mobility diameters above 1.4 nm. The resolving power at 200 nm is between 40 and 60. Certain design compromises have been made to enable the wide adoption of this instrument in conventional aerosol measurements, making it comparable to broadly used contemporary commercial DMAs in portability, complexity, and cost. Yet, the high flow rate capability provides drastic advantages in resolution, sensitivity and size range over more conventional DMAs. This DMA is nevertheless inferior in resolution to more specialized instruments developed for studies of either nanoparticles or viruses. The inner electrode is a 1° half-angle cone accelerating mildly the flow. Critical dimensions in mm are: outer radius R₂ = 19.58; inner radius at the outlet slit R₁ = 14.34; axial distance between slits L = 85.94.

{"title":"A high performance differential mobility analyzer for the masses","authors":"Juan Fernandez de la Mora , Jerzy Kozlovski","doi":"10.1016/j.jaerosci.2024.106522","DOIUrl":"10.1016/j.jaerosci.2024.106522","url":null,"abstract":"<div><div>A hand-held Differential Mobility Analyzer (DMA) weighting 4 kg is developed to operate laminarly at many hundreds of L/min, while covering at unusually high resolution the 1–200 nm size range. Coupled with a small and efficient portable vacuum cleaner pump requiring no cooling, a resolving power of 10 or more is obtained at mobility diameters above 1.4 nm. The resolving power at 200 nm is between 40 and 60. Certain design compromises have been made to enable the wide adoption of this instrument in conventional aerosol measurements, making it comparable to broadly used contemporary commercial DMAs in portability, complexity, and cost. Yet, the high flow rate capability provides drastic advantages in resolution, sensitivity and size range over more conventional DMAs. This DMA is nevertheless inferior in resolution to more specialized instruments developed for studies of either nanoparticles or viruses. The inner electrode is a 1° half-angle cone accelerating mildly the flow. Critical dimensions in mm are: outer radius R<sub>2</sub> = 19.58; inner radius at the outlet slit R<sub>1</sub> = 14.34; axial distance between slits L = 85.94.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106522"},"PeriodicalIF":3.9,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102201","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}

引用次数: 0