Particle emission during manufacturing processes, whether chemical, physical or mechanical can represent a serious danger for environment and for occupational safety. Especially machining processes, particle emission ...Particle emission during manufacturing processes, whether chemical, physical or mechanical can represent a serious danger for environment and for occupational safety. Especially machining processes, particle emission could have an important impact on shop floor air quality and might jeopardise workers’ health. It is therefore important to find ways of reducing the particle emission at the source of manufacturing processes. To do so, there is a need to know the size, the quantity and the distribution of particles produced by processes currently used in industry. In this study, investigations are done to compare the particle emission (PM2.5) when polishing two granites (black and white). The black granite contained low Si concentration (about 10% Si) and the white granite contained high Si concentration (about 50% Si). Particle emission was monitored using the DustTrak II equipment with 2.5 μm impactor. The particle grain size was evaluated using X-ray diffraction techniques. Machining conditions leading to the generation of finer particles were identified.展开更多
The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM 2.5 showed an increasing trend. To understand pollution characteristics of PM 2.5 and its relationship...The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM 2.5 showed an increasing trend. To understand pollution characteristics of PM 2.5 and its relationship with the meteorological conditions in Beijing, a one-year monitoring of PM 2.5 mass concentration and correspondent meteorological parameters was performed in Beijing in 2001. The PM 2.5 levels in Beijing were very high, the annual average PM 2.5 concentration in 2001 was 7 times of the National Ambient Air Quality Standards proposed by US EPA. The major chemical compositions were organics, sulfate, crustals and nitrate. It was found that the mass concentrations of PM 2.5 were influenced by meteorological conditions. The correlation between the mass concentrations of PM 2.5 and the relative humidity was found. And the correlation became closer at higher relative humidity. And the mass concentrations of PM 2.5 were negtive-correlated to wind speeds, but the correlation between the mass concentration of PM 2.5 and wind speed was not good at stronger wind.展开更多
The particle matter,particularly the suspended particle matter(PM≤2.5)in the air is not only a risk factor for human health,but also affects the survival and physiological features of plants.Plants show advantages in...The particle matter,particularly the suspended particle matter(PM≤2.5)in the air is not only a risk factor for human health,but also affects the survival and physiological features of plants.Plants show advantages in the adsorption of particle matter,while the factors,such as the leaf shape,leaf distribution density and leaf surface microstructure,such as grooves,folds,stomata,flocculent projections,micro-roughness,long fuzz,short pubescence,wax and secretory products,appeared to play an important role determing their absorption capacity.In this paper,the research progress on the capture or adsorption of atmospheric particles was summarized,and the forest vegetation and woody plants were discuessed.In addition,special attentions were paid to the effect of haze-fog weather on greenhouse plant,the different responses of plant leaves to dust particles and suspended particles,as well as the effect of suspended particles on morphological change of plants.In the future,research should focus on the mechanism of the influence of particulate matter on plants.More advanced effective and convenient research methods like spectral detection method also need to be developed.This paper may provide reference for future studies on plants’response to haze and particle matter.展开更多
The Brussels Capital Region has difficulties in meeting the stringent EU daily limit value for PM10 in all its measuring sites. Postponing the attainment of the deadline was not granted by the EU Commission, mainly du...The Brussels Capital Region has difficulties in meeting the stringent EU daily limit value for PM10 in all its measuring sites. Postponing the attainment of the deadline was not granted by the EU Commission, mainly due to insufficient judged measures to reduce road traffic emissions. However, a thorough analysis of the data makes clear that neither the particle mass concentration (PM10 and PM2.5) nor the particle number concentration are specific metrics for evaluating the particle pollution originated by traffic. In fact, increased formation of secondary aerosol, together with adverse meteorological conditions and the (re) suspension of the coarser fraction are by far the three main explanations for the numerous PM10 exceeding values. From our experience, amongst the particles measured, only the results for Black Carbon (BC), mainly present in the lower submicron range, are reflective of the direct influence of local traffic. Measured at two traffic sites along with PM mass and number concentrations, the data for Black Carbon show a striking correlation with nitrogen monoxide, a parameter strongly related with the proximity of the local traffic. The correlation factor between Black Carbon data and NO or NOX is much higher than between Black Carbon and the PM mass or number concentration. Therefore the assessment of traffic related particles should consider Black Carbon rather than PM10 or PM2.5.展开更多
In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples...In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry（ICP-MS）.Then chemical mass balance（CMB） model and factor analysis（FA） method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan.展开更多
Despite international efforts to limit worker exposure to coal dust,it continues to impact the health of thousands of miners across Europe.Airborne coal dust has been studied to improve risk models and its control to ...Despite international efforts to limit worker exposure to coal dust,it continues to impact the health of thousands of miners across Europe.Airborne coal dust has been studied to improve risk models and its control to protect workers.Particle size distribution analyses shows that using spraying systems to suppress airborne dusts can reduce particulate matter concentrations and that coals with higher ash yields produce finer dust.There are marked chemical differences between parent coals and relatively coarse deposited dusts(up to _(500)μm,DD_(500)).Enrichments in Ca,K,Ba,Se,Pb,Cr,Mo,Ni and especially As,Sn,Cu,Zn and Sb in the finest respirable dust fractions could originate from:(i)mechanical machinery wear;(ii)variations in coal mineralogy;(iii)coal fly ash used in shotcrete,and carbonates used to reduce the risk of explosions.Unusual enrichments in Ca in mine dusts are attributed to the use of such concrete,and elevated K to raised levels of phyllosilicate mineral matter.Sulphur concentrations are higher in the parent coal than in the DD_(500),probably due to relatively lower levels of organic matter.Mass concentrations of all elements observed in this study remained below occupational exposure limits.展开更多
Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Ar...Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Araraquara City (Southeast Brazil) is surrounded by sugar-cane plantations, which are burned to facilitate the harvesting;this process causes environmental pollution due to the large amounts of soot that are released into the atmosphere. In this work, the elemental composition of PM2.5 was studied in two scenarios, namely in sugar-cane harvesting (HV) and in non-harvesting (NHV) seasons. The sampling strategy included one campaign in each season. PM2.5 was collected using a dichotomous sampler (10 L·min-1, 24 h) with PTFE filters. Information concerning the bulk elemental concentration was provided by energy-dispersive X-ray fluorescence. Enrichment factor analysis indicated that S, Cl, K, Cr, Ni, Cu, Zn, As, Cd and Pb were highly enriched relative to their crustal ratios (to Al). Principal component analysis was used to get some insight about the sources of the elements. Principal component 1 (PC1) explained 30.5% of data variance. The elements that had high loading (>0.7) were: S, Cr, As, and Pb;these are associated with combustion of fossil fuels. In principal component 2 (PC2), Cl, Cu, Zn, and Cd showed high loadings;these elements are associated with biomass burning. The Ni concentration found is three times larger than the threshold of risk for lung cancer, as recommended by the World Health Organization.展开更多
This paper describes the evaluation of trace element composition of atmospheric aerosol particles (PM<sub>2.5</sub> and PM<sub>10</sub>) and their influence on air quality in the largest indust...This paper describes the evaluation of trace element composition of atmospheric aerosol particles (PM<sub>2.5</sub> and PM<sub>10</sub>) and their influence on air quality in the largest industrial area of Abidjan city, C?te d’Ivoire. Multi-week sampling was conducted in an urban site (industrial area) in Abidjan from April 2018 to July 2019. The mean mass concentration was 48.83 ± 15.24 μg/m<sup>3</sup> for PM<sub>2.5</sub> and 77.34 ± 10.91 μg/m<sup>3</sup> for PM<sub>10</sub>, with significant temporal variability. The average ratio of PM<sub>2.5</sub>/PM<sub>10</sub> was 0.64 ± 0.21. The concentration of BC in PM<sub>2.5</sub> and PM<sub>10</sub> was respectively 52.32 ± 7.48 μg/m<sup>3</sup> and 52.26 ± 12.07 μg/m<sup>3</sup>. Twenty-two elements: Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Zr and Pb were analysed by Energy Dispersive X-ray Fluorescence (EDXRF). Elemental composition data were modeled using principal component analysis (PCA) with varimax rotation to determine two (2) and four (4) dominant source categories contributing to PM<sub>2.5</sub> and PM<sub>10</sub> respectively. In the case of fine particles PM<sub>2.5</sub>, the possible sources were Industrial activities and non-exhaust emissions, exhaust emissions. The PM<sub>10</sub> sources were industrial activities and non-exhaust emissions, industrial processes, mineral dust, and waste combustion.展开更多
文摘Particle emission during manufacturing processes, whether chemical, physical or mechanical can represent a serious danger for environment and for occupational safety. Especially machining processes, particle emission could have an important impact on shop floor air quality and might jeopardise workers’ health. It is therefore important to find ways of reducing the particle emission at the source of manufacturing processes. To do so, there is a need to know the size, the quantity and the distribution of particles produced by processes currently used in industry. In this study, investigations are done to compare the particle emission (PM2.5) when polishing two granites (black and white). The black granite contained low Si concentration (about 10% Si) and the white granite contained high Si concentration (about 50% Si). Particle emission was monitored using the DustTrak II equipment with 2.5 μm impactor. The particle grain size was evaluated using X-ray diffraction techniques. Machining conditions leading to the generation of finer particles were identified.
文摘The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM 2.5 showed an increasing trend. To understand pollution characteristics of PM 2.5 and its relationship with the meteorological conditions in Beijing, a one-year monitoring of PM 2.5 mass concentration and correspondent meteorological parameters was performed in Beijing in 2001. The PM 2.5 levels in Beijing were very high, the annual average PM 2.5 concentration in 2001 was 7 times of the National Ambient Air Quality Standards proposed by US EPA. The major chemical compositions were organics, sulfate, crustals and nitrate. It was found that the mass concentrations of PM 2.5 were influenced by meteorological conditions. The correlation between the mass concentrations of PM 2.5 and the relative humidity was found. And the correlation became closer at higher relative humidity. And the mass concentrations of PM 2.5 were negtive-correlated to wind speeds, but the correlation between the mass concentration of PM 2.5 and wind speed was not good at stronger wind.
基金This work was funded under the auspices of the National Natural Science Foundation for Young Scientists of China(31801259)the Science and Technology Development Project of Jilin Province(20170204020NY).
文摘The particle matter,particularly the suspended particle matter(PM≤2.5)in the air is not only a risk factor for human health,but also affects the survival and physiological features of plants.Plants show advantages in the adsorption of particle matter,while the factors,such as the leaf shape,leaf distribution density and leaf surface microstructure,such as grooves,folds,stomata,flocculent projections,micro-roughness,long fuzz,short pubescence,wax and secretory products,appeared to play an important role determing their absorption capacity.In this paper,the research progress on the capture or adsorption of atmospheric particles was summarized,and the forest vegetation and woody plants were discuessed.In addition,special attentions were paid to the effect of haze-fog weather on greenhouse plant,the different responses of plant leaves to dust particles and suspended particles,as well as the effect of suspended particles on morphological change of plants.In the future,research should focus on the mechanism of the influence of particulate matter on plants.More advanced effective and convenient research methods like spectral detection method also need to be developed.This paper may provide reference for future studies on plants’response to haze and particle matter.
文摘The Brussels Capital Region has difficulties in meeting the stringent EU daily limit value for PM10 in all its measuring sites. Postponing the attainment of the deadline was not granted by the EU Commission, mainly due to insufficient judged measures to reduce road traffic emissions. However, a thorough analysis of the data makes clear that neither the particle mass concentration (PM10 and PM2.5) nor the particle number concentration are specific metrics for evaluating the particle pollution originated by traffic. In fact, increased formation of secondary aerosol, together with adverse meteorological conditions and the (re) suspension of the coarser fraction are by far the three main explanations for the numerous PM10 exceeding values. From our experience, amongst the particles measured, only the results for Black Carbon (BC), mainly present in the lower submicron range, are reflective of the direct influence of local traffic. Measured at two traffic sites along with PM mass and number concentrations, the data for Black Carbon show a striking correlation with nitrogen monoxide, a parameter strongly related with the proximity of the local traffic. The correlation factor between Black Carbon data and NO or NOX is much higher than between Black Carbon and the PM mass or number concentration. Therefore the assessment of traffic related particles should consider Black Carbon rather than PM10 or PM2.5.
基金Supported by the Natural Basic Research Program of China(No.2005CB422207)the Fund of Eco-enviromental Impacts and Protection in Devoloping and Utilizing of Oil-shale Resources(No.OSR-01-06)
文摘In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry（ICP-MS）.Then chemical mass balance（CMB） model and factor analysis（FA） method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan.
基金European Commission Research Fund for Coal and Steel(Grant Agreement Number–754205)Generalitat de Catalunya(SGR41).Centre of Excellence Severo Ochoa—Spanish Ministry of Science and Innovation(Project CEX2018-000794-S).
文摘Despite international efforts to limit worker exposure to coal dust,it continues to impact the health of thousands of miners across Europe.Airborne coal dust has been studied to improve risk models and its control to protect workers.Particle size distribution analyses shows that using spraying systems to suppress airborne dusts can reduce particulate matter concentrations and that coals with higher ash yields produce finer dust.There are marked chemical differences between parent coals and relatively coarse deposited dusts(up to _(500)μm,DD_(500)).Enrichments in Ca,K,Ba,Se,Pb,Cr,Mo,Ni and especially As,Sn,Cu,Zn and Sb in the finest respirable dust fractions could originate from:(i)mechanical machinery wear;(ii)variations in coal mineralogy;(iii)coal fly ash used in shotcrete,and carbonates used to reduce the risk of explosions.Unusual enrichments in Ca in mine dusts are attributed to the use of such concrete,and elevated K to raised levels of phyllosilicate mineral matter.Sulphur concentrations are higher in the parent coal than in the DD_(500),probably due to relatively lower levels of organic matter.Mass concentrations of all elements observed in this study remained below occupational exposure limits.
文摘Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Araraquara City (Southeast Brazil) is surrounded by sugar-cane plantations, which are burned to facilitate the harvesting;this process causes environmental pollution due to the large amounts of soot that are released into the atmosphere. In this work, the elemental composition of PM2.5 was studied in two scenarios, namely in sugar-cane harvesting (HV) and in non-harvesting (NHV) seasons. The sampling strategy included one campaign in each season. PM2.5 was collected using a dichotomous sampler (10 L·min-1, 24 h) with PTFE filters. Information concerning the bulk elemental concentration was provided by energy-dispersive X-ray fluorescence. Enrichment factor analysis indicated that S, Cl, K, Cr, Ni, Cu, Zn, As, Cd and Pb were highly enriched relative to their crustal ratios (to Al). Principal component analysis was used to get some insight about the sources of the elements. Principal component 1 (PC1) explained 30.5% of data variance. The elements that had high loading (>0.7) were: S, Cr, As, and Pb;these are associated with combustion of fossil fuels. In principal component 2 (PC2), Cl, Cu, Zn, and Cd showed high loadings;these elements are associated with biomass burning. The Ni concentration found is three times larger than the threshold of risk for lung cancer, as recommended by the World Health Organization.
文摘This paper describes the evaluation of trace element composition of atmospheric aerosol particles (PM<sub>2.5</sub> and PM<sub>10</sub>) and their influence on air quality in the largest industrial area of Abidjan city, C?te d’Ivoire. Multi-week sampling was conducted in an urban site (industrial area) in Abidjan from April 2018 to July 2019. The mean mass concentration was 48.83 ± 15.24 μg/m<sup>3</sup> for PM<sub>2.5</sub> and 77.34 ± 10.91 μg/m<sup>3</sup> for PM<sub>10</sub>, with significant temporal variability. The average ratio of PM<sub>2.5</sub>/PM<sub>10</sub> was 0.64 ± 0.21. The concentration of BC in PM<sub>2.5</sub> and PM<sub>10</sub> was respectively 52.32 ± 7.48 μg/m<sup>3</sup> and 52.26 ± 12.07 μg/m<sup>3</sup>. Twenty-two elements: Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Zr and Pb were analysed by Energy Dispersive X-ray Fluorescence (EDXRF). Elemental composition data were modeled using principal component analysis (PCA) with varimax rotation to determine two (2) and four (4) dominant source categories contributing to PM<sub>2.5</sub> and PM<sub>10</sub> respectively. In the case of fine particles PM<sub>2.5</sub>, the possible sources were Industrial activities and non-exhaust emissions, exhaust emissions. The PM<sub>10</sub> sources were industrial activities and non-exhaust emissions, industrial processes, mineral dust, and waste combustion.
