Journal of Aerosol Science最新文献_第2页

Characterization of highly conducting ionic liquid (EMI-BF4)mEMIn+ nanoclusters injected into dielectrics to produce compound electrosprays

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106493

Carlos Larriba-Andaluz , Juan Fernández de la Mora

Electrospraying of dielectric liquids presents unique challenges compared to conducting liquids, as it requires external charge injection. This manuscript further explores the Charge Injection Atomization (CIA) technique, which employs two concentric capillaries to create a compound electrospray. The inner liquid is an ionic liquid (IL), which injects nanodrops and perhaps also ions into the dielectric. The evaporation of the dielectric liberates these charged particles into the gas phase, where they are analyzed with a Differential Mobility Analyzer (DMA). The mobility spectra show very narrow peaks of high mobility (corresponding to ions) and broader, lower mobility peaks representing IL nanodrops. In this work, the effects of both the ionic liquid and dielectric flow rates on droplet diameter and charge are thoroughly studied. Through a simple assumption that the mobility of the droplets agrees with Stokes-Millikan and the condition that the droplets are spherical of known density, the diameter and mass over charge,

m / z

are determined, revealing average

m / z

values ranging from 7 to 90 kDa and diameters from 3 to 35 nm. The charge density of the droplets seems to suggest that they are charged to a fraction between 50 and 100% of the Rayleigh limit and are affected mostly by the ionic liquid flow rate as expected. Given the broad interest of IL, the controlled size production of nanoclusters in dielectrics can have important implications in synthesis and catalysis, polymer chemistry, electrochemistry, microemulsions and biotechnology.

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引用次数: 0

Use of electric field to enhance collection of ultrafine particles using quartz crystal microbalance

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106495

Nichakran Vichayarom , Kata Jaruwongrungsee , Panich Intra , Thi-Cuc Le , Chuen-Jinn Tsai , John Morris , Racha Dejchanchaiwong , Perapong Tekasakul

In the present study, a Quartz Crystal Microbalance (QCM) technique was used in conjunction with an electric field to measure particle mass concentration of ultrafine particles (UFPs). Using Sauerbrey's equation, particle mass concentration can be estimated from the QCM frequency change. An electric field enhanced particle collection efficiency on the QCM surface, focusing on particle sizes ranging from 30 to 300 nm in aerodynamic diameter. Polydisperse NaCl was used to investigate the relationship between particle mass concentration and two key parameters - collection efficiency and mass sensitivity. Data were obtained using the Scanning Mobility Particle Sizer (SMPS). Particle concentrations were varied from 23.3 to 522.8 μg/m³ for applied voltages from 0 to 1 kV at 5 L/min flow. The optimal condition was achieved at 1 kV at a concentration of 23.3 μg/m³, where total collection efficiencies were between 90.3 and 99.5%. The mass accumulated on the QCM surface was linear with the frequency shift measured by a QCM detector, yielding the mass sensitivity of 0.177 μg/Hz. Based on the minimum frequency shift and general concentration of atmospheric UFPs, the QCM detector is appropriate for hourly measurement. This was confirmed by a good agreement between the predicted particle mass deposition by the mass sensitivity of the QCM and the measured one with a linear fit (

r^{2}

= 0.997).

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引用次数: 0

Algorithm for improving the sizing accuracy in real-time bioaerosol single particle mass spectrometer

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106501

Shaoyong Li , Lingjun Tang , Jingzhen Li , Zhanming Su , Zhengxu Huang , Mei Li , Wei Gao , Xue Li , Guohua Zhang , Lei Li

The newly developed bioaerosol single particle mass spectrometer (Bio-SPAMS) has been innovatively designed for its optical sizing system. The first laser beam in the previous single particle mass spectrometer was split into near distance double beams, similar to the design of APS (Aerodynamic Particle Sizer) and SBS-LIBS (Single Beam Splitting-Laser Induced Breakdown Spectroscopy). All the particles focused by the aerodynamic lens can be sized and got number concentration statistic. However, due to the imperfect beam quality and the large scattering intensity of the large-sized particles, there may be some noise in the scattered signals, particle diameter measured by this sizing system was often larger than actual value if the same trigger threshold was set. In this study, when measuring PSL microspheres with diameters of 1.9, 3.1, and 4.9 μm, the identification rates of the fixed threshold algorithm were only 75.25%, 55.26%, and 0.27%, respectively. To address such issue, we developed a dynamic threshold waveform recognition algorithm based on field programmable gate array (FPGA), which could process the photoelectric signals collected by a photomultiplier tube (PMT) in real time. The algorithm can dynamically adjust the trigger threshold of the collected scattered signals and accurately calculate the interval time between the near distance double beam. For PSL microspheres with diameters of 1.9, 3.1, and 4.9 μm, the accuracy of the dynamic threshold algorithm increased by 19.09%, 25.72%, and 88.20%, respectively. This algorithm effectively solves the problem of particle sizing deviation, and improves the particle size measurement accuracy of the bioaerosol mass spectrometer in a wide particle size range from 0.3–6 μm.

{"title":"Algorithm for improving the sizing accuracy in real-time bioaerosol single particle mass spectrometer","authors":"Shaoyong Li , Lingjun Tang , Jingzhen Li , Zhanming Su , Zhengxu Huang , Mei Li , Wei Gao , Xue Li , Guohua Zhang , Lei Li","doi":"10.1016/j.jaerosci.2024.106501","DOIUrl":"10.1016/j.jaerosci.2024.106501","url":null,"abstract":"<div><div>The newly developed bioaerosol single particle mass spectrometer (Bio-SPAMS) has been innovatively designed for its optical sizing system. The first laser beam in the previous single particle mass spectrometer was split into near distance double beams, similar to the design of APS (Aerodynamic Particle Sizer) and SBS-LIBS (Single Beam Splitting-Laser Induced Breakdown Spectroscopy). All the particles focused by the aerodynamic lens can be sized and got number concentration statistic. However, due to the imperfect beam quality and the large scattering intensity of the large-sized particles, there may be some noise in the scattered signals, particle diameter measured by this sizing system was often larger than actual value if the same trigger threshold was set. In this study, when measuring PSL microspheres with diameters of 1.9, 3.1, and 4.9 μm, the identification rates of the fixed threshold algorithm were only 75.25%, 55.26%, and 0.27%, respectively. To address such issue, we developed a dynamic threshold waveform recognition algorithm based on field programmable gate array (FPGA), which could process the photoelectric signals collected by a photomultiplier tube (PMT) in real time. The algorithm can dynamically adjust the trigger threshold of the collected scattered signals and accurately calculate the interval time between the near distance double beam. For PSL microspheres with diameters of 1.9, 3.1, and 4.9 μm, the accuracy of the dynamic threshold algorithm increased by 19.09%, 25.72%, and 88.20%, respectively. This algorithm effectively solves the problem of particle sizing deviation, and improves the particle size measurement accuracy of the bioaerosol mass spectrometer in a wide particle size range from 0.3–6 μm.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"184 ","pages":"Article 106501"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143155339","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

Photophoretic forces in coated-hollow microspheres

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106510

D.J.S. Pereira, M.R.O. Panão

Photophoresis is a phenomenon that generates thermally induced forces on microparticles immersed in a gas when exposed to a light beam such as a laser. Enhancing photophoretic forces depends on the alignment of the geometrical, thermal, and optical properties of the particles. The hypothesis explored here considers coated hollow microspheres to be a promising approach to this challenge. Therefore, we first present a photophoresis model for a three-layered microsphere in the slip-flow regime by applying Navier–Stokes equations with corrected boundary conditions. The numerical approaches used to compute the heat source function

q_{g}

consider the Lorenz–Mie theory, and validate the results with those of previous studies. When applied to a copper-coated glass bubble, the model analyzes the photophoretic force as a function of the coating thickness considering several shell thicknesses. The results indicate that nanometric-scale coatings initially enhance the force to a maximum, beyond which the high thermal conductivity of copper leads to a reduction in the force. For coatings with thicknesses above

100

nm, the force becomes insensitive to the shell thickness, demonstrating the dominance of copper in optical and thermal phenomena. Suppose that the fabrication of an optimal coating thickness cannot be precisely achieved. This study suggests depositing excess coating to ensure higher photophoretic forces, thereby providing a framework for optimizing the microparticle design in photophoretic applications. Future work will include validation through experiments and finding analytical solutions for integrals associated with internal heat generation using the Lorenz–Mie theory, which holds great promise for advancing our understanding of photophoresis.

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引用次数: 0

Study on the atomization characteristics of gel by liquid carbon dioxide

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106496

Changchun Liu , Shuang Peng , Xue Du , Pengzhi Wu , Yushan Li , Zairong Feng

Super absorbent polymer (SAP) gel materials have emerged as a focal point of research in the firefighting domain, owing to their remarkable water retention capabilities and inherent flexibility. However, due to the high viscosity of the gel material, it is usually treated with a medium atomization method. Liquid CO₂ has a very high expansion coefficient, and when released, it can effectively drive away oxygen in the fire area. With the development of carbon capture and utilization (CCU) technology, more and more CO₂ being stored in liquid form in cylinders, making it meaningful to explore using liquid CO₂ as a medium for atomizing the gel. This paper proposes using the liquid CO₂ as the atomization medium and designs a hybrid atomization system. The system utilizes the large amount of energy released when liquid carbon dioxide turns into gas, thereby enhancing the atomization effect for high-viscosity fluids and helping to carry out carbon capture and utilization (CCU) work simultaneously. The influences of the inlet diameter of liquid CO₂ (d₀), the number of outlet holes of mixed liquid (N_holes), and the gel concentration (C) on the atomization characteristics of the gel jet were investigated. The research results indicate that with an increase in d₀, the spray range, spray width, and spray cone angle increase correspondingly, while the spray particle sizes D₃₂ and Dv90 decrease accordingly. With an increase in N_holes, the spray range and the particle sizes D₃₂ and Dv90 show an increasing trend, while the spray cone angle and spray width decrease correspondingly. As the gel concentration increases, the spray range, spray width, and spray cone angle decrease, while the particle sizes D₃₂ and Dv90 increase accordingly.

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引用次数: 0

Feasibility of online optical diagnostics during gas-phase synthesis of few-layer graphene based on elastic light scattering measurements

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106497

Halil İbrahim Yazıcı , Christof Schulz , Kyle J. Daun

Gas-phase synthesis is a promising method for scalable production of high-quality free-standing few-layer graphene (FLG) particles. This study assesses the feasibility of elastic light scattering in characterizing particle morphology and distinguishing FLG from soot-like particles that may also be produced concurrently during gas-phase synthesis. FLG particle morphology is modeled based on tomographic electron microscopy images of FLG particles produced within a plasma reactor, whereas synthetic soot particles are generated via a cluster–cluster aggregation algorithm based on morphological parameters typical of flame soot. Light scattering properties of ensembles of synthetic FLG and soot particles are simulated via the discrete dipole approximation (DDA) and the multi-sphere T-matrix method, respectively. Angle-resolved scattering properties of ensembles of FLG and soot particles are analyzed to evaluate the feasibility of scattering-based diagnostics and identify potential measurement configurations for characterizing particle morphology. Overall, certain scattering properties, especially the depolarization ratio, are observed to be sensitive to the distinctive morphological aspects of FLG and soot, which highlights the promise of light scattering-based diagnostics for characterizing morphology during gas-phase synthesis of FLG.

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引用次数: 0

Capture of wind-blown particles during transport through a vegetative barrier

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106517

Mohammad Jabarifar, Jeffrey S. Marshall

This study presents an efficient computational method for predicting the capture by vegetative barriers of wind-blown particles, such as sand, snowflakes, and exhaust from vehicular exhaust. The method assumes that the vegetative barrier is composed of a line of trees, where synthetic trees are formed using a network of cylindrical elements representing branches and needles, as is typical of pines and other evergreen vegetation. Computational fluid dynamics simulations are employed to determine the average wind velocity at the front of the vegetation and to calculate the particle flux entering the vegetative barrier. The vegetative barrier is treated as a heterogeneous filter medium, and an efficient method is used to compute the capture efficiency and penetration of particles into the vegetation. The particle capture computation method employs an estimate of the single fiber efficiency for each cylindrical branch/needle element based on models for finite Reynolds number particle capture from the literature. The method was employed for different vegetative barriers, which were characterized by varying porosities to assess their impact on particle capture efficiency. The proposed prediction approach is important for assessing effectiveness of vegetative barriers for protection of roadways from blowing snow and dust and for estimation of rate of vehicular pollution damage to roadside trees.

{"title":"Capture of wind-blown particles during transport through a vegetative barrier","authors":"Mohammad Jabarifar, Jeffrey S. Marshall","doi":"10.1016/j.jaerosci.2024.106517","DOIUrl":"10.1016/j.jaerosci.2024.106517","url":null,"abstract":"<div><div>This study presents an efficient computational method for predicting the capture by vegetative barriers of wind-blown particles, such as sand, snowflakes, and exhaust from vehicular exhaust. The method assumes that the vegetative barrier is composed of a line of trees, where synthetic trees are formed using a network of cylindrical elements representing branches and needles, as is typical of pines and other evergreen vegetation. Computational fluid dynamics simulations are employed to determine the average wind velocity at the front of the vegetation and to calculate the particle flux entering the vegetative barrier. The vegetative barrier is treated as a heterogeneous filter medium, and an efficient method is used to compute the capture efficiency and penetration of particles into the vegetation. The particle capture computation method employs an estimate of the single fiber efficiency for each cylindrical branch/needle element based on models for finite Reynolds number particle capture from the literature. The method was employed for different vegetative barriers, which were characterized by varying porosities to assess their impact on particle capture efficiency. The proposed prediction approach is important for assessing effectiveness of vegetative barriers for protection of roadways from blowing snow and dust and for estimation of rate of vehicular pollution damage to roadside trees.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"184 ","pages":"Article 106517"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143155338","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

Field calibration and performance evaluation of low-cost sensors for monitoring airborne PM in the occupational mining environment

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106519

Abhishek Penchala , Aditya Kumar Patra , Namrata Mishra , Samrat Santra

Surface mining operations emit particulate matter (PM) with varying sizes and compositions, adversely affecting the health of mine workers and adjoining communities. Measurements for regulatory compliance at present are obtained by bulky instruments, which are costly and provide data averaged over a period of time. Recently, low-cost PM sensors (LCPMS) have been increasingly used in indoor and outdoor environments for monitoring real-time PM concentrations with high spatial and temporal resolution. No comprehensive study has been undertaken to evaluate the performance of LCPMS when exposed to uncontrolled high dust concentrations prevailing in the occupational mining environment. The study aimed to achieve this by deploying three sensors (OPC N3, SPS30, and SDS011) in a highly mechanized surface coal mine. A comparative assessment of these sensors has been conducted by calibrating them against a research-grade reference instrument in uncontrolled indoor, outdoor, and mining environments. The performance of OPC N3 and SPS30 sensors was found to be good, with high linearity (R² = 0.90 – 0.99) and precision (CV = 2 – 6%). Incorporating the monitored local meteorological conditions and PM proportions improved the performance of the applied calibration models. The decision tree-based regression model performed better (R² = 0.95 – 99; RMSE = 0.8 – 11.4; MAE = 0.4 – 5.3) compared to the multiple linear model in accurately predicting reference equivalent PM mass concentration measurements. The comprehensive performance evaluation of LCPMS in this study highlights its potential applications in the different occupational environments particularly for monitoring the personal exposure of industry workers.

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引用次数: 0

Optimization of nozzle geometry for virtual impaction across more than one decade in particle size

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106516

Li Li , Mckenna E. Relling , Susmita Islam , Yaakov Y. Knobloch , Stephanie M. Eilts , Bernard A. Olson , Christopher J. Hogan Jr. , Tomoya Tamadate

Virtual Impactors (VIs) are devices used to inertially concentrate particles from a larger set of sample flow streamlines to a smaller fraction of minor flow streamlines. Ideally, a VI would function for particles across a wide size range, from submicrometer to supermicrometer diameters. However, pushing VI operation to concentrate submicrometer particles typically leads to inlet losses, as well as overfocusing and internal losses, for supermicrometer particles. Here, we utilized a combination of particle trajectory calculations and experiments to design a round-nozzle VI capable of concentrating submicrometer particles while maintaining performance for particles approaching 10

μ m

in diameter. First, we simulated particle trajectories in more than 140 test nozzle geometries, varying inlet length, diameter, angle, and concavity. Simulating atmospheric pressure upstream, and nozzle Mach numbers exceeding 0.3 (compressible flow), nozzles were then ”Scored” based on their ability to inertially focus particles in the 100 nm to 10

μ m

diameter range to the inner 10% of their area, at the nozzle outlet. Subsequently, we used two high-scoring nozzle geometries to design and contruct single nozzle VIs, which were experimentally tested with monodisperse particles in the 100 nm - 10

μ m

diameter range. Based on these measurements, a nozzle geometry capable of functioning for particles down below 500 nm while maintaining the ability to concentrate particles above 5

μ m

was then utilized in designing a single-stage, 16-nozzle VI. Operating with a sample flow of 40

L \min^{- 1}

and a minor flow of 1.2

L \min^{- 1}

, the multinozzle VI enables concentration increases by a factor in excess of 25 across more than a decade in particle diameter.

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引用次数: 0

Respiratory particle super-emissive Italian words and effect of articulation manner during children speaking

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

Journal of Aerosol Science

Pub Date : 2025-02-01 DOI: 10.1016/j.jaerosci.2024.106514

Elisa Caracci , Giorgio Buonanno , Rossella Avignone , Luca Stabile

Speaking represents one of the most occurrence respiratory activities influencing the airborne transmission of respiratory pathogens. To date, the positive correlation between the amplitude of human speech and respiratory particles emitted is proven, but information about the effect of articulation manner on the respiratory particle emission is weakly investigated. The few existing studies involves adults and languages other than Italian. To fill this gap of knowledge, this study analyzed the words affecting the most the respiratory particle emission, here named “super-emissive”, and the effect of the articulation manner of consonants on disyllabic words. To achieve this goal, 10 children reading an Italian phonetically balanced word list (at “speaking” and “loudly speaking” voice intensity levels) were analyzed. The findings of this study are of great interest since that, for the first time, are focused on children during Italian speaking. The main results evidence that some words exceed the average concentration level within a given speech compared to others. This can be due to the word length, as in “Nabucodonosor” in which several phonemes fall into the unit of time, but also can be dependent on the articulation manner of consonants. Indeed, an in-depth analysis of disyllabic words containing the same type of consonants revealed that affricates due to their composition, as in “ciccio”, are responsible for the highest emission of respiratory particles respect to nasals, fricatives, approximants and occlusives.

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引用次数: 0