Thi-Cuc Le, Pallavi Gajanan Barhate, Kai-Jing Zhen, Manisha Mishra, David. Y. H. Pui, Chuen-Jinn Tsai
{"title":"Optimization of sampling conditions to minimize sampling errors of both PM <sub>2.5</sub> mass and its semi-volatile inorganic ion concentrations","authors":"Thi-Cuc Le, Pallavi Gajanan Barhate, Kai-Jing Zhen, Manisha Mishra, David. Y. H. Pui, Chuen-Jinn Tsai","doi":"10.1080/02786826.2023.2265454","DOIUrl":"https://doi.org/10.1080/02786826.2023.2265454","url":null,"abstract":"ABSTRACTThe accurate measurement of PM2.5 and its inorganic matters (IMs) is crucial for compliance monitoring and understanding particle formation. However, semi-volatile IMs (SVIMs) like NH4+, NO3− and Cl− tend to evaporate from particles, causing sampling artifacts. The evaporation loss occurs due to many factors making the quantitative prediction difficult. This study aimed to investigate the evaporation loss of SVIMs in PM2.5 under different sampling conditions. In the field tests, when a normal single Teflon filter sampler (STF), which is like a Federal Reference Method (FRM) sampler, was used to sample PM2.5 at ambient conditions, a significant SVIM evaporation loss was observed, resulting in negative biases for total IMs (-25.68 ± 3.25%) and PM2.5 concentrations (-9.87 ± 4.27%). But if PM2.5 was sampled by a chilled Teflon filter sampler (CTF) at 4 0C following aerosol dehumidification so that relative humidity (RH) was controlled to within the 10-20% range (RHd), evaporation loss was minimized with a bias of < ±10% for both total IMs and PM2.5 based on the reference data. When RHd is below 10%, both IMs and PM2.5 are under-measured, but only PM2.5 is over-measured when RHd is >20%. A model considering predictable saturation ratios for NH4+, NO3− and Cl− under various pressure drop, temperature and RH conditions was developed to predict accurately the actual concentrations of PM2.5 and its SVIMs for the STF. Additionally, the ISORROPIA-II model predicted SVIMs effectively for the CTF. In summary, using the CTF at optimized sampling conditions can achieve accurate measurement of both SVIMs and PM2.5 concentrations simultaneously.DisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also. AcknowledgementsThis work was supported by the Ministry of Science and Technology, Taiwan (contract MOST 111-2221-E-A49-057-MY3), the Ministry of Education, the Higher Education Sprout Project of National Yang Ming Chiao Tung University, and the Academic-Industry Research Hub of People and Earth (AIR HoPE).Disclosure statementThe authors report there are no competing interests to declare.","PeriodicalId":7474,"journal":{"name":"Aerosol Science and Technology","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135346718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Ana C. Morales, Brianna N. Peterson, Steven A. Sharpe, Shelby M. Huston, Jay M. Tomlin, Felipe A. Rivera-Adorno, Ryan C. Moffet, Alla Zelenyuk, Alexander Laskin
{"title":"Multi-modal Chemical Characterization of Highly Viscous Submicrometer Organic Particles.","authors":"Ana C. Morales, Brianna N. Peterson, Steven A. Sharpe, Shelby M. Huston, Jay M. Tomlin, Felipe A. Rivera-Adorno, Ryan C. Moffet, Alla Zelenyuk, Alexander Laskin","doi":"10.1080/02786826.2023.2266494","DOIUrl":"https://doi.org/10.1080/02786826.2023.2266494","url":null,"abstract":"AbstractDistinguishing highly viscous organic particles within complex mixtures of atmospheric aerosol and accurate descriptions of their composition, size distributions, and mixing states are challenges at the forefront of aerosol measurement science and technology. Here, we present results obtained from complementary single-particle measurement techniques employed for the in-depth characterization of highly viscous particles. We demonstrate advantages and synergy of this multi-modal particle characterization approach based on the analysis of individual viscous particles formed in the air-discharged waste produced by a common sewer pipe rehabilitation technology. Using oil immersion flow microscopy, we investigate particle size distributions and morphology of colloidal components present in field-collected aqueous waste condensates. We compare these results with corresponding measurements of viscous particles formed in drying droplets of the aerosolized discharged waste. The colloidal components and viscous particles were found to be approximately 10 µm and 0.5 µm, respectively. The aerosolized viscous particles exhibited a spherical morphology, while the colloidal particles appeared noticeably fractal, resembling fragments of a cured composite material. Chemical imaging of the viscous particles collected on substrates was performed using scanning electron microscopy and soft X-ray spectro-microscopy techniques. Through these methods, comprehensive description of these particles emerged, confirming their high solid-like viscosity, wide-ranging sizes, diverse carbon speciation with high degrees of oxygenation, and high organic volume fractions. The aerosolized viscous particles were further characterized using high-throughput single particle mass spectrometry. This technique provides real-time measurements of composition, size, and morphological metrics for large numbers of individual particles, enabling the identification of their distinct mass spectrometric signatures.DisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":7474,"journal":{"name":"Aerosol Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134974972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Meredith Schervish, Neil M Donahue, Manabu Shiraiwa
{"title":"Effects of volatility, viscosity, and non-ideality on particle–particle mixing timescales of secondary organic aerosols","authors":"Meredith Schervish, Neil M Donahue, Manabu Shiraiwa","doi":"10.1080/02786826.2023.2256827","DOIUrl":"https://doi.org/10.1080/02786826.2023.2256827","url":null,"abstract":"Different populations of aerosol are constantly mixed throughout the atmosphere. Large-scale models often assume no particle–particle mixing or fast mixing among aerosol populations, so that they stay externally mixed or instantaneously form internal mixtures. We apply the kinetic multilayer model of gas–particle interactions (KM-GAP) to simulate the evaporation of semi-volatile species from one particle population and partitioning into another population with various phase states and nonideal mixing conditions. We find that the particle–particle mixing timescale (τmix) is prolonged when the semi-volatile species transport to a population in which it is miscible, as more mass must be transported. Extremes of volatility prolong the τmix, as low-volatility species evaporate slowly, while high-volatility species condense slowly. When the bulk diffusivities of the two populations are greater than 10−15 cm2 s−1, semi-volatile species mix rapidly; otherwise, the τmix can be prolonged beyond 1 h. We apply KM-GAP to particle–particle mixing experiments of H-toluene SOA into D-toluene SOA and limonene SOA, showing that τmix is prolonged when toluene SOA is highly viscous, while initial partitioning of gas phase semi-volatile species from toluene SOA into limonene SOA is rapid because of the low viscosity of limonene SOA. Simulations of mixing toluene SOA and β-caryophyllene SOA indicate that the apparent discrepancy of limited mixing under conditions where both are predicted to have low viscosity are explained by limited miscibility of the semi-volatile components. Our study demonstrates that particle–particle mixing timescales are affected by a complex interplay among volatility, diffusion limitations, and non-ideal miscibility.","PeriodicalId":7474,"journal":{"name":"Aerosol Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134886879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Nicolas Castro, Qiang Wang, Jingjie Zhang, Weiling Li, Y. Pithawalla, Michael Oldham, Ali Rostami
{"title":"Application of a Physical Model of the Human Mouth and Throat to Study the Complex Dynamics of Inhaled Aerosols","authors":"Nicolas Castro, Qiang Wang, Jingjie Zhang, Weiling Li, Y. Pithawalla, Michael Oldham, Ali Rostami","doi":"10.1080/02786826.2023.2253302","DOIUrl":"https://doi.org/10.1080/02786826.2023.2253302","url":null,"abstract":"Abstract A unique adult human mouth/throat physical model has been developed to study e-cigarette aerosol dynamics during inhalation. The 3D printed physical model was created from the CT scan of a 28 yr. old healthy male. Internal walls of the physical model were lined with a thin layer of cotton gauze that can be saturated with water to replicate the high relative humidity conditions in a human Oral/Pharyngeal cavity. Aerosol hygroscopic growth and deposition inside the physical model from a cartomizer style e-cigarette using a prototype e-liquid formulation was determined by measuring cumulative aerosol mass from five puffs (gravimetric) and for individual constituents (propylene glycol, glycerol, and nicotine) from a single puff (GC/MS analysis). Measurements were taken at constant temperature of 37 °C under both wet and dry inner wall conditions for a for a 3-sec. 55 mL puff. The condition of holding aerosol inside the physical model without airflow for a duration of 3-sec. was also included. For the same puffing conditions of 3-sec puff of 55 mL and a 3-sec. puff hold time, dry wall conditions resulted in a mean aerosol mass loss of 20.9 ± 3.8%, while the total aerosol mass was increased by 150.9 ± 19% under wet wall condition when compared to total aerosol mass entering the physical model entrance. The dramatic increase is due to water vapor uptake by the aerosol particles when flowing through the wetted physical model. Aerosol evolution of individual chemical constituent analysis appeared to vary as a function of volatility.","PeriodicalId":7474,"journal":{"name":"Aerosol Science and Technology","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48850190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}