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
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
目的研究刹车制动来源颗粒物对机体的潜在危害。方法研磨刹车片颗粒、硫化锑颗粒,小鼠通过气管灌注暴露1个月后,观察肺、心脏、肝等内脏器官病理改变,同时用流式细胞术分析外周血巨噬细胞和自然调节T淋巴细胞(regulatory T cell,Treg)...目的研究刹车制动来源颗粒物对机体的潜在危害。方法研磨刹车片颗粒、硫化锑颗粒,小鼠通过气管灌注暴露1个月后,观察肺、心脏、肝等内脏器官病理改变,同时用流式细胞术分析外周血巨噬细胞和自然调节T淋巴细胞(regulatory T cell,Treg)的变化。结果刹车片颗粒及硫化锑颗粒暴露小鼠肺泡壁外源物质沉积,血管周围出现明显的炎症细胞浸润并随着暴露浓度的增加而加重,同时可出现心脏血管炎症和微血栓以及肝细胞肿胀等病理改变;Treg细胞减少,硫化锑组和低剂量刹车片组巨噬细胞增加,同时M2型巨噬细胞比例下调。结论刹车片颗粒及其成分硫化锑颗粒暴露对小鼠肺、心脏、肝等脏器具有不同程度的毒性作用,并对免疫系统造成了影响,提示刹车来源的空气污染存在潜在健康危害。展开更多
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.
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.
文摘目的研究刹车制动来源颗粒物对机体的潜在危害。方法研磨刹车片颗粒、硫化锑颗粒,小鼠通过气管灌注暴露1个月后,观察肺、心脏、肝等内脏器官病理改变,同时用流式细胞术分析外周血巨噬细胞和自然调节T淋巴细胞(regulatory T cell,Treg)的变化。结果刹车片颗粒及硫化锑颗粒暴露小鼠肺泡壁外源物质沉积,血管周围出现明显的炎症细胞浸润并随着暴露浓度的增加而加重,同时可出现心脏血管炎症和微血栓以及肝细胞肿胀等病理改变;Treg细胞减少,硫化锑组和低剂量刹车片组巨噬细胞增加,同时M2型巨噬细胞比例下调。结论刹车片颗粒及其成分硫化锑颗粒暴露对小鼠肺、心脏、肝等脏器具有不同程度的毒性作用,并对免疫系统造成了影响,提示刹车来源的空气污染存在潜在健康危害。
