Oyun-Erdene Otgonbyamba, G. Ganbat, Ser-Od Khuyag, Enkhjargal Altangerel, Bilguun Ganbold, Altangadas Bayanjargal, Altangerel Bat-Erdene, Bataa Chuluunbaatar, B. Badrakh, S. Batbaatar
This study presents levels of volatile organic compounds (VOCs) measured indoors for the first time in Ulaanbaatar, Mongolia, and quantifies the health risk for children emphasizing the urgent need to improve control for indoor VOCs sources. The 583 samples collected at 144 sites, including new buildings, old apartments, schools, workplaces, kindergartens, baishin, and Mongolian traditional gers , hospitals, schools, and shopping centers are analyzed. Formaldehyde was detected in 95.7% of the samples, while benzene was in 24.2%. The levels of benzene, toluene, and xylene in new and old buildings and apartments exceed the recommended values of AGÖF for volatile organic compounds in indoor air. The probabilistic Monte Carlo simulation method was used to estimate the risk exposure of four types of VOCs (benzene, formaldehyde, toluene, and m,p-xylene) to the health of the study population. The risk of cancer for benzene and formaldehyde is high in the age group of 7 months–4 years, m,p-xylene, and toluene show non-cancer risk in this age group.
{"title":"Health Risk Assessment of Volatile Organic Compounds for Children in Indoor Air, Ulaanbaatar, Mongolia","authors":"Oyun-Erdene Otgonbyamba, G. Ganbat, Ser-Od Khuyag, Enkhjargal Altangerel, Bilguun Ganbold, Altangadas Bayanjargal, Altangerel Bat-Erdene, Bataa Chuluunbaatar, B. Badrakh, S. Batbaatar","doi":"10.4209/aaqr.230028","DOIUrl":"https://doi.org/10.4209/aaqr.230028","url":null,"abstract":"This study presents levels of volatile organic compounds (VOCs) measured indoors for the first time in Ulaanbaatar, Mongolia, and quantifies the health risk for children emphasizing the urgent need to improve control for indoor VOCs sources. The 583 samples collected at 144 sites, including new buildings, old apartments, schools, workplaces, kindergartens, baishin, and Mongolian traditional gers , hospitals, schools, and shopping centers are analyzed. Formaldehyde was detected in 95.7% of the samples, while benzene was in 24.2%. The levels of benzene, toluene, and xylene in new and old buildings and apartments exceed the recommended values of AGÖF for volatile organic compounds in indoor air. The probabilistic Monte Carlo simulation method was used to estimate the risk exposure of four types of VOCs (benzene, formaldehyde, toluene, and m,p-xylene) to the health of the study population. The risk of cancer for benzene and formaldehyde is high in the age group of 7 months–4 years, m,p-xylene, and toluene show non-cancer risk in this age group.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70296727","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}
This study aims to estimate the amount of air pollutants emitted from heavy industrial facilities in North Korea. The heavy industry sector in North Korea was classified according to the South Korean definition, and the air pollutant emissions that it generated were estimated for 2017. Emissions of carbon monoxide (CO), nitrogen oxides (NO x ), and sulfur oxides (SO x ) by the heavy industry sector in North Korea were 22, 73, and 31%, respectively, of those in South Korea’ air pollutant emissions. Moreover, the CO, NO x , and SO x emissions comprised 0.6, 124, and 24%, respectively, of the total air pollutant emission in North Korea estimated from the Emissions Database for Global Atmospheric Research version 5.0 (EDGAR v5.0). Geographically, the NO x emissions were concentrated in the western part of North Korea, while CO and SO x were concentrated in North Hamgyong Province.
{"title":"Estimation of Air Pollutant Emissions from Heavy Industry Sector in North Korea","authors":"Y. Lee, Y. Kim, M. Yeo","doi":"10.4209/aaqr.230066","DOIUrl":"https://doi.org/10.4209/aaqr.230066","url":null,"abstract":"This study aims to estimate the amount of air pollutants emitted from heavy industrial facilities in North Korea. The heavy industry sector in North Korea was classified according to the South Korean definition, and the air pollutant emissions that it generated were estimated for 2017. Emissions of carbon monoxide (CO), nitrogen oxides (NO x ), and sulfur oxides (SO x ) by the heavy industry sector in North Korea were 22, 73, and 31%, respectively, of those in South Korea’ air pollutant emissions. Moreover, the CO, NO x , and SO x emissions comprised 0.6, 124, and 24%, respectively, of the total air pollutant emission in North Korea estimated from the Emissions Database for Global Atmospheric Research version 5.0 (EDGAR v5.0). Geographically, the NO x emissions were concentrated in the western part of North Korea, while CO and SO x were concentrated in North Hamgyong Province.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70297065","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}
Optical remote sensing of PM2.5 concentration complements ground-based in situ sampler observations and depends on aerosol extinction-to-mass conversion and meteorological factors. Based on Mie scattering theory, we derived a non-linear analytical expression among the PM2.5 mass concentration, aerosol extinction coefficient, and hygroscopic factor. We analyzed 1-year data of aerosol size distribution, PM2.5, visibility, and relative humidity (RH) and refined the exponential factors for improving PM2.5 estimated from the aerosol extinction coefficient in Hefei, China. Aerosol size distribution data on adjacent days were used to approximate the hygroscopic factors of the aerosols. The measured PM2.5 in 2020 was used to refine the exponential factors relevant to the large aerosol extinction coefficient and RH in the analytical function. Next, we evaluated the derived PM2.5 from aerosol extinction with the tapered element oscillating microbalance (TEOM), which independently observed PM2.5 in January 2021; their comparisons indicated good consistency and strong correlation with a linear correlation coefficient of R2=0.76. Finally, by applying the analytical function of PM2.5 and aerosol extinction, we obtained the spatial and vertical distribution of PM2.5 from the NASA/CALIPSO-observed aerosol extinction profiles, which showed reasonable agreement and good correlation with the TEOM-measured PM2.5 in several major cities in Anhui Province, China.
{"title":"Analysis of Non-linear Relationship of PM2.5 Mass Concentration with Aerosol Extinction Coefficient and RH in Hefei, China","authors":"Yinan Chen, Shiguo Zhang, Yonghua Wu, Kee Yuan, Jian Huang, Dongfeng Shi, Shunxing Hu","doi":"10.4209/aaqr.230139","DOIUrl":"https://doi.org/10.4209/aaqr.230139","url":null,"abstract":"Optical remote sensing of PM2.5 concentration complements ground-based in situ sampler observations and depends on aerosol extinction-to-mass conversion and meteorological factors. Based on Mie scattering theory, we derived a non-linear analytical expression among the PM2.5 mass concentration, aerosol extinction coefficient, and hygroscopic factor. We analyzed 1-year data of aerosol size distribution, PM2.5, visibility, and relative humidity (RH) and refined the exponential factors for improving PM2.5 estimated from the aerosol extinction coefficient in Hefei, China. Aerosol size distribution data on adjacent days were used to approximate the hygroscopic factors of the aerosols. The measured PM2.5 in 2020 was used to refine the exponential factors relevant to the large aerosol extinction coefficient and RH in the analytical function. Next, we evaluated the derived PM2.5 from aerosol extinction with the tapered element oscillating microbalance (TEOM), which independently observed PM2.5 in January 2021; their comparisons indicated good consistency and strong correlation with a linear correlation coefficient of R2=0.76. Finally, by applying the analytical function of PM2.5 and aerosol extinction, we obtained the spatial and vertical distribution of PM2.5 from the NASA/CALIPSO-observed aerosol extinction profiles, which showed reasonable agreement and good correlation with the TEOM-measured PM2.5 in several major cities in Anhui Province, China.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135059410","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}
Emissions of total particulate matter (TPM) from stationary combustion sources consist of both filterable particulate matter (FPM) and condensable particulate matter (CPM). According to the study's findings, CPM emissions contributed significantly to the overall concentration of TPM. Therefore, there has been a growing focus on the physicochemical properties and control strategy of CPM. Firstly, this paper systematically reviewed the formation, composition, characteristics, and methods of removing CPM. Secondly, integrating the current removal methods, a cold electrode electrostatic precipitator (CE-ESP) based on the synergistic effect of multi-field coupled force on CPM coagulation and removal was put forward and installed. Thirdly, case studies of CE-ESP on CPM removal were conducted in a municipal solid waste incineration plant and a coal-fired power plant. The results showed that the removal efficiency of CPM could reach as high as 93%. The CE-ESP had a significant removal effect on both organic and inorganic substances in CPM.
{"title":"New Insights into the Synergistic Effect on Condensable Particulate Matter Based on the Formation, Characteristics and Removal","authors":"Wenting Liu, Xin Wang, Bowen Zhao, Jianyi Lu","doi":"10.4209/aaqr.230145","DOIUrl":"https://doi.org/10.4209/aaqr.230145","url":null,"abstract":"Emissions of total particulate matter (TPM) from stationary combustion sources consist of both filterable particulate matter (FPM) and condensable particulate matter (CPM). According to the study's findings, CPM emissions contributed significantly to the overall concentration of TPM. Therefore, there has been a growing focus on the physicochemical properties and control strategy of CPM. Firstly, this paper systematically reviewed the formation, composition, characteristics, and methods of removing CPM. Secondly, integrating the current removal methods, a cold electrode electrostatic precipitator (CE-ESP) based on the synergistic effect of multi-field coupled force on CPM coagulation and removal was put forward and installed. Thirdly, case studies of CE-ESP on CPM removal were conducted in a municipal solid waste incineration plant and a coal-fired power plant. The results showed that the removal efficiency of CPM could reach as high as 93%. The CE-ESP had a significant removal effect on both organic and inorganic substances in CPM.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136005101","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}
Aerosol acidity is an important parameter in aerosol science that affects many chemical reactions in the atmosphere, and it is often estimated using chemical thermodynamic models. The Extended Aerosol Inorganic Model IV (E-AIM IV) is frequently used for this purpose; however, due to the limited number of available direct measurement methods of aerosol acidity, there is still a certain degree of uncertainty with regard to how accurately the simulation results reflect reality. In this study, a new pH testing paper method for the direct measurement of aerosol pH is used to measure the pH (pHmeas) of aerosol particle samples. Based on the data of the ionic constituents of the samples, the E-AIM IV model is then used to estimate aerosol pH (pHest). This study provides a comparison of pHmeas and pHest, revealing that the relationship is satisfactorily approximated by a simple linear regression of pHest = 1.05pHmeas + 0.38 (R2 = 0.90). The strong correlation and slope very close to unity indicate that the pH testing paper method corroborates the outputs of the E-AIM IV model.
{"title":"Comparison of Aerosol Acidity Based on a Direct Measurement Method and a Chemical Thermodynamic Model","authors":"Qinping Song, Kazuo Osada","doi":"10.4209/aaqr.230096","DOIUrl":"https://doi.org/10.4209/aaqr.230096","url":null,"abstract":"Aerosol acidity is an important parameter in aerosol science that affects many chemical reactions in the atmosphere, and it is often estimated using chemical thermodynamic models. The Extended Aerosol Inorganic Model IV (E-AIM IV) is frequently used for this purpose; however, due to the limited number of available direct measurement methods of aerosol acidity, there is still a certain degree of uncertainty with regard to how accurately the simulation results reflect reality. In this study, a new pH testing paper method for the direct measurement of aerosol pH is used to measure the pH (pHmeas) of aerosol particle samples. Based on the data of the ionic constituents of the samples, the E-AIM IV model is then used to estimate aerosol pH (pHest). This study provides a comparison of pHmeas and pHest, revealing that the relationship is satisfactorily approximated by a simple linear regression of pHest = 1.05pHmeas + 0.38 (R2 = 0.90). The strong correlation and slope very close to unity indicate that the pH testing paper method corroborates the outputs of the E-AIM IV model.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135653426","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}
Airborne microorganisms are associated with human health and awareness of the important influence of nano-sized extracellular vesicles (EVs) on health has risen. Thus, we analyzed the micro-sized microbes (m-MBs) and nano-sized microbial EVs (n-MEVs) of outdoor and indoor air through a field study in Seoul, Korea. We conducted 16S rDNA-based metagenomic analysis of m-MBs and n-MEVs in outdoor airborne dust (OAD), indoor airborne dust (IAD), and indoor dust from carpets (IDC). The dominant taxa in OAD were altered depending upon the outside environment, such as sunny, haze, and rainy. Also, dominant taxa in IAD and IDC were changed depending on the outside environment. In addition, there were differences of microbiome composition and diversity between the m-MB and n-MEV in OAD, IAD, and IDC. m-MB in OAD were more correlated with that of IDC, whereas n-MEVs in OAD were more related to those in IAD. Thus, indoor bioaerosols can be affected by different source according to bioaerosol size. Additionally, risk of bioaerosols can be different according to dominant taxa, and therefore we suggested that further study for risk of dominant taxa according to environments is necessary. We suggested that nano-sized microbial EVs should be included as parameters to manage air quality
{"title":"Composition Analysis of Airborne Microbiota in Outdoor and Indoor Based on Dust Separated by Micro-sized and Nano-sized","authors":"Jinho Yang, J. Seo, Y. Jee, Yoon Kim, J. Sohn","doi":"10.4209/aaqr.210231","DOIUrl":"https://doi.org/10.4209/aaqr.210231","url":null,"abstract":"Airborne microorganisms are associated with human health and awareness of the important influence of nano-sized extracellular vesicles (EVs) on health has risen. Thus, we analyzed the micro-sized microbes (m-MBs) and nano-sized microbial EVs (n-MEVs) of outdoor and indoor air through a field study in Seoul, Korea. We conducted 16S rDNA-based metagenomic analysis of m-MBs and n-MEVs in outdoor airborne dust (OAD), indoor airborne dust (IAD), and indoor dust from carpets (IDC). The dominant taxa in OAD were altered depending upon the outside environment, such as sunny, haze, and rainy. Also, dominant taxa in IAD and IDC were changed depending on the outside environment. In addition, there were differences of microbiome composition and diversity between the m-MB and n-MEV in OAD, IAD, and IDC. m-MB in OAD were more correlated with that of IDC, whereas n-MEVs in OAD were more related to those in IAD. Thus, indoor bioaerosols can be affected by different source according to bioaerosol size. Additionally, risk of bioaerosols can be different according to dominant taxa, and therefore we suggested that further study for risk of dominant taxa according to environments is necessary. We suggested that nano-sized microbial EVs should be included as parameters to manage air quality","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70290545","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}
The outbreak of COVID-19 pandemic in northern Taiwan led to the implementation of Level 3 alert measures during 2021 and thereby impacted the air quality significantly, which provided an unprecedented opportunity to better understand the control strategies on air pollutants in the future. This study investigated the variations in sources, chemical characteristics and human health risks of PM2.5 comprehensively. The PM2.5 mass concentrations decreased from pre-alert to Level 3 alert by 49.4%, and the inorganic ions, i.e., NH4+, NO3- and SO42-, dropped even more by 71%, 90% and 52%, respectively. Nonetheless, organic matter (OM) and elemental carbon (EC) simply decreased by 36% and 13%, which caused the chemical composition of PM2.5 to change so that the carbonaceous matter in PM2.5 dominated instead of the inorganic ions. Correlation-based hierarchical clustering analysis further showed that PM2.5 was clustered with carbonaceous matter during the Level 3 alert, while that clustered with inorganic ions during both pre-alert and post-alert periods. Moreover, 6 sources of PM2.5 were identified by positive matrix factorization (PMF), in which secondary nitrate (i.e., aging traffic aerosols) exhibited the most significant decrease and yet primary traffic-related emissions, dominated by carbonaceous matter, changed insignificantly. This implied that secondary traffic-related aerosols could be easily controlled when traffic volume declined, while primary traffic source needs more efforts in the future, especially for the reduction of carbonaceous matter. Therefore, cleaner energy for vehicles is still needed. Assessments of both carcinogenic risk and non-carcinogenic risk induced by the trace elements in PM2.5 showed insignificant decrease, which can be attributed to the factories that did not shut down during Level 3 alert. This study serves as a metric to underpin the mitigation strategies of air pollution in the future and highlights the importance of carbonaceous matter for the reduction in PM2.5.
{"title":"Implications of the Improvement in Atmospheric Fine Particles: A Case Study of COVID-19 Pandemic in Northern Taiwan","authors":"Chuanqun Huang, Yi-Ru Ko, Tzu-Chi Lin, Yu-Hsiang Cheng, Yu-Cheng Chen, Y. Ting","doi":"10.4209/aaqr.220329","DOIUrl":"https://doi.org/10.4209/aaqr.220329","url":null,"abstract":"The outbreak of COVID-19 pandemic in northern Taiwan led to the implementation of Level 3 alert measures during 2021 and thereby impacted the air quality significantly, which provided an unprecedented opportunity to better understand the control strategies on air pollutants in the future. This study investigated the variations in sources, chemical characteristics and human health risks of PM2.5 comprehensively. The PM2.5 mass concentrations decreased from pre-alert to Level 3 alert by 49.4%, and the inorganic ions, i.e., NH4+, NO3- and SO42-, dropped even more by 71%, 90% and 52%, respectively. Nonetheless, organic matter (OM) and elemental carbon (EC) simply decreased by 36% and 13%, which caused the chemical composition of PM2.5 to change so that the carbonaceous matter in PM2.5 dominated instead of the inorganic ions. Correlation-based hierarchical clustering analysis further showed that PM2.5 was clustered with carbonaceous matter during the Level 3 alert, while that clustered with inorganic ions during both pre-alert and post-alert periods. Moreover, 6 sources of PM2.5 were identified by positive matrix factorization (PMF), in which secondary nitrate (i.e., aging traffic aerosols) exhibited the most significant decrease and yet primary traffic-related emissions, dominated by carbonaceous matter, changed insignificantly. This implied that secondary traffic-related aerosols could be easily controlled when traffic volume declined, while primary traffic source needs more efforts in the future, especially for the reduction of carbonaceous matter. Therefore, cleaner energy for vehicles is still needed. Assessments of both carcinogenic risk and non-carcinogenic risk induced by the trace elements in PM2.5 showed insignificant decrease, which can be attributed to the factories that did not shut down during Level 3 alert. This study serves as a metric to underpin the mitigation strategies of air pollution in the future and highlights the importance of carbonaceous matter for the reduction in PM2.5.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70294499","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}
Due to the increase in human activities and the application of nanotechnology, people's exposure to nano and submicron particles is increasing. Conventional particle separation technologies, such as electrostatic precipitators, cyclone, wet washing, and filtration method, cannot work well. In addition, the fiber diameter and pore size of the traditional fiber filter material is too large, and the bulk density is difficult to control. Nanofiber membranes have a large surface area, small pore size and high porosity. The nanofiber membranes prepared by electrospinning technology are easy to intercept submicron and nanoparticles. Furthermore, the electrospinning technology is simple to operate, makes fibers of various materials easy, and is convenient for assembly and replacement. The most common bacteria are Escherichia coli, which harms the ecological environment and human health. Therefore, this study used bacteria and particles as the target pollutants and controlled by prepared nanostructured materials doped with metals and ions. In order to improve the treatment efficiency of particles and bacteria, this study added various metals and ions to nylon 6 nanofibers and explored the antibacterial and filterability of artificial fibrils. Different operation parameters, such as types of metal, types of ion, metal and concentration, and surface velocity, were also investigated to prepare various fibers to make the best performance fiber. In addition, the best-operating conditions could be obtained through a filtration test. Different salts, metals and metal ions with different concentrations, three metal oxides (TiO 2 , CeO 2 , and ZnO) and three ions (Ag + , K + , and Na + ) were used to test the filtration performance of various particle sizes for the best metal ion concentration, best filtration and bacterial removal performance. The experimental results show that the filtration efficiency of the composite fiber can reach 99%, and the composite fiber sprayed with a self-made antibacterial liquid has the best antibacterial ability.
{"title":"Particle Removal and Antibacterial of Nanofiber Doped with Metal and Ions Prepared by Electrospinning","authors":"Yinglu Jiang, RD Hope Tamboboy Cayron, Yu-Chen Cheng, Chang-Tang Chang","doi":"10.4209/aaqr.220342","DOIUrl":"https://doi.org/10.4209/aaqr.220342","url":null,"abstract":"Due to the increase in human activities and the application of nanotechnology, people's exposure to nano and submicron particles is increasing. Conventional particle separation technologies, such as electrostatic precipitators, cyclone, wet washing, and filtration method, cannot work well. In addition, the fiber diameter and pore size of the traditional fiber filter material is too large, and the bulk density is difficult to control. Nanofiber membranes have a large surface area, small pore size and high porosity. The nanofiber membranes prepared by electrospinning technology are easy to intercept submicron and nanoparticles. Furthermore, the electrospinning technology is simple to operate, makes fibers of various materials easy, and is convenient for assembly and replacement. The most common bacteria are Escherichia coli, which harms the ecological environment and human health. Therefore, this study used bacteria and particles as the target pollutants and controlled by prepared nanostructured materials doped with metals and ions. In order to improve the treatment efficiency of particles and bacteria, this study added various metals and ions to nylon 6 nanofibers and explored the antibacterial and filterability of artificial fibrils. Different operation parameters, such as types of metal, types of ion, metal and concentration, and surface velocity, were also investigated to prepare various fibers to make the best performance fiber. In addition, the best-operating conditions could be obtained through a filtration test. Different salts, metals and metal ions with different concentrations, three metal oxides (TiO 2 , CeO 2 , and ZnO) and three ions (Ag + , K + , and Na + ) were used to test the filtration performance of various particle sizes for the best metal ion concentration, best filtration and bacterial removal performance. The experimental results show that the filtration efficiency of the composite fiber can reach 99%, and the composite fiber sprayed with a self-made antibacterial liquid has the best antibacterial ability.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70294573","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}
Yu-hua Li, Sheng-Hua Yang, C. Yuan, Huazhen Shen, C. Hung
Volatile organic compounds (VOCs) are air pollutants associated with health problem. Paints mixed with photocatalytic (PC) materials are considered to be effective in the removal of VOCs. Therefore, this investigation aimed to produce a novel visible induced photocatalyst component in paint. The synthesized photocatalysts (i.e., Ag-TiO 2 and Fe-TiO 2 ) were self-prepared by sol-gel method and further used to produce paints. The effects of the paints on VOC (i.e., acetone) degradation under the irradiation of visible light were tested in a batch PC reactor and an environmental chamber. In order to evaluate the control effect of VOCs using the paint, a simulated test was conducted in a real room. The results of batch experiments showed that the degradation efficiencies of acetone by the paints were lower than that by the related photocatalysts. The paints made of 3% Fe-TiO 2 and 1% Ag-TiO 2 achieved the highest acetone degradation efficiency of 32.7 and 21.3%, respectively. The degradation test conducted in the environmental chamber indicated that the degradation efficiencies of acetone were 24.9, 46.2, and 32.4% for the paints made of TiO 2 , 3% Fe-TiO 2 and 1% Ag-TiO 2 , respectively. It was evidently provided that the paint made of 3% Fe-TiO 2 could effectively degrade organic pollutants in indoor environments.
挥发性有机化合物(VOCs)是与健康问题相关的空气污染物。涂料与光催化(PC)材料混合被认为是有效的去除挥发性有机化合物。因此,本研究旨在制备一种新型的涂料可见光诱导光催化剂。采用溶胶-凝胶法制备了ag - tio2和fe - tio2光催化剂,并将其用于涂料的制备。在间歇式PC反应器和环境箱中测试了涂料在可见光照射下对VOC(即丙酮)降解的影响。为了评价该涂料对VOCs的控制效果,在实际室内进行了模拟试验。批量实验结果表明,涂料对丙酮的降解效率低于相关光催化剂。由3% fe - tio2和1% ag - tio2组成的涂料对丙酮的降解效率最高,分别为32.7%和21.3%。在环境室中进行的降解试验表明,对于由tio2、3% fe - tio2和1% ag - tio2制成的涂料,丙酮的降解效率分别为24.9%、46.2和32.4%。结果表明,含3% fe - tio2的涂料能有效降解室内环境中的有机污染物。
{"title":"Photocatalytic Degradation of Gaseous Acetone by Photocatalysts with Visible Light and their Potential Applications in Painting","authors":"Yu-hua Li, Sheng-Hua Yang, C. Yuan, Huazhen Shen, C. Hung","doi":"10.4209/aaqr.220358","DOIUrl":"https://doi.org/10.4209/aaqr.220358","url":null,"abstract":"Volatile organic compounds (VOCs) are air pollutants associated with health problem. Paints mixed with photocatalytic (PC) materials are considered to be effective in the removal of VOCs. Therefore, this investigation aimed to produce a novel visible induced photocatalyst component in paint. The synthesized photocatalysts (i.e., Ag-TiO 2 and Fe-TiO 2 ) were self-prepared by sol-gel method and further used to produce paints. The effects of the paints on VOC (i.e., acetone) degradation under the irradiation of visible light were tested in a batch PC reactor and an environmental chamber. In order to evaluate the control effect of VOCs using the paint, a simulated test was conducted in a real room. The results of batch experiments showed that the degradation efficiencies of acetone by the paints were lower than that by the related photocatalysts. The paints made of 3% Fe-TiO 2 and 1% Ag-TiO 2 achieved the highest acetone degradation efficiency of 32.7 and 21.3%, respectively. The degradation test conducted in the environmental chamber indicated that the degradation efficiencies of acetone were 24.9, 46.2, and 32.4% for the paints made of TiO 2 , 3% Fe-TiO 2 and 1% Ag-TiO 2 , respectively. It was evidently provided that the paint made of 3% Fe-TiO 2 could effectively degrade organic pollutants in indoor environments.","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70295059","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}
Zhen Liu, Da-Ren Chen, Q. Niu, Desmond Asiedu Mensah, Z. Ji
Electret media have the advantage of enhancing the particle collection efficiency while keeping/reducing the media pressure drop by the electrostatic mechanisms in addition to the mechanical ones. This study investigated the effect of operational pressure on the filtration performance of electret filter media. Experiments was conducted at the pressures in the range of 0.33–3 atm and using DMA-classified particles ranging in electrical mobility sizes of 10–600 nm. The penetration of particles in the neutral, singly charged and Fuchs’ bipolar charge states of two electret media (both charged and discharged) were measured. The single fiber efficiency due to the induced and Coulombic forces, i.e., η In and η C , were obtained. It is found that both efficiencies are a function of the filtration pressure (i
{"title":"Particle Collection of Electret Media under Different Filtration Pressures","authors":"Zhen Liu, Da-Ren Chen, Q. Niu, Desmond Asiedu Mensah, Z. Ji","doi":"10.4209/aaqr.220405","DOIUrl":"https://doi.org/10.4209/aaqr.220405","url":null,"abstract":"Electret media have the advantage of enhancing the particle collection efficiency while keeping/reducing the media pressure drop by the electrostatic mechanisms in addition to the mechanical ones. This study investigated the effect of operational pressure on the filtration performance of electret filter media. Experiments was conducted at the pressures in the range of 0.33–3 atm and using DMA-classified particles ranging in electrical mobility sizes of 10–600 nm. The penetration of particles in the neutral, singly charged and Fuchs’ bipolar charge states of two electret media (both charged and discharged) were measured. The single fiber efficiency due to the induced and Coulombic forces, i.e., η In and η C , were obtained. It is found that both efficiencies are a function of the filtration pressure (i","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70295100","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}