Exposure to air pollutants such as PM_(10),PM_(2.5),PM_(0.1),O_(3),CO,NO2,and SO_(2),and biological pollutants are important factors causing the evolution and furtherance of obstructive lung diseases(OLD),including as...Exposure to air pollutants such as PM_(10),PM_(2.5),PM_(0.1),O_(3),CO,NO2,and SO_(2),and biological pollutants are important factors causing the evolution and furtherance of obstructive lung diseases(OLD),including asthma and chronic obstructive pulmonary disease(COPD).Asthma is the most frequent chronic inflammatory airway disease,characterized by breathlessness,wheezing,chest tightness,and cough,together with the presence of exaggerated expiratory airflow fluctuation that varies over time.COPD is a heterogeneous lung condition characterized by chronic respiratory symptoms such as dyspnea,cough,expectoration,and/or exacerbations due to abnormalities of the airways and/or alveoli that cause persistent,often progressive,airflow obstruction.Understanding the molecular mechanisms and cellular processes based on the development of OLD on exposure to air pollutants will provide insights into the solution of pathogenesis,prevention,and treatment of these conditions.The molecular mechanisms and cellular process involved in signal transduction pathway plays a role in the binding of extracellular signaling molecules and ligands to receptors placed on the cell surface or on the inner side cell that trigger inflammation that occurs,especially when something important enters the cell to bring into a cascade response.This binding then alters the cell metabolism,shape,and gene expression in the airway.This review aimed to reveal the effect of air pollutants on the molecular mechanisms and cellular processes involved in the signal transduction pathways in OLD.展开更多
Emissions of air pollutants and greenhouse gases into the atmosphere in Antarctica from power plants with diesel generators(the main sources of energy at Antarctic research stations and the main stationary sources of ...Emissions of air pollutants and greenhouse gases into the atmosphere in Antarctica from power plants with diesel generators(the main sources of energy at Antarctic research stations and the main stationary sources of anthropogenic emissions in the Antarctic)were assessed.A bottom-up approach was used to compile an emission inventory for the Antarctic.This involved estimating emissions at various spatial levels by sequentially aggregating estimate emissions from point emission sources.This is the first time this approach has been proposed and used.Emissions of CO2,NOx,particulate matter(PM10),and CO in the modern period were estimated at the research station,geographic region,natural domain,biogeographic region,continent section,and whole continent scales.Yearly emissions are presented here,but the approach allows emissions at different averaging periods to be estimated.This means mean or maximum yearly,monthly,daily,or hourly emissions can be estimated.The estimates could be used to model pollutant transmission and dispersion,assess the impacts of pollutants,and develop emission forecasts for various scenarios.展开更多
Removal of air pollutants, such as nitrogen and sulphur containing compounds from a model oil (dodecane) was studied. An ionic liquid (1-ethyl-3-methylimidazolium chloride [C2mim] [Cl]) was used as an extractant. Liqu...Removal of air pollutants, such as nitrogen and sulphur containing compounds from a model oil (dodecane) was studied. An ionic liquid (1-ethyl-3-methylimidazolium chloride [C2mim] [Cl]) was used as an extractant. Liquid-liquid extraction by using 1-ethyl-3-methylimidazolium chloride [C2mim] [Cl] was found to be a very promising method for the removal of N- and S-compounds. This was evaluated by using a model oil (dodecane) with indole as a neutral nitrogen compound and pyridine as a basic nitrogen compound. Dibenzothiophene (DBT) was used as a sulphur compound. An extraction capacity of up to 90 wt% was achieved for the model oil containing pyridine, while only 76 wt% of indole in the oil was extracted. The extraction capacity of a model sulphur compound DBT was found to be up to 99 wt%. Regeneration of the spent ionic liquid was carried out with toluene back-extraction. A 1:1 toluene-to-IL wt ratio was performed at room temperature. It was observed that, for the spent ionic liquid containing DBT as a model compound more than 85 wt% (corresponding 3852 mg/kg) could be removed from the oil. After the second regeneration cycle, 86 wt% of the DBT was recovered from the ionic liquid to toluene. In the case of indole as the nitrogen containing species, more than 99 wt%, (corresponding to 2993 mg/kg) of the original indole was transferred from the model oil to the ionic liquid. After the first-regeneration cycle of the spent ionic liquid, 54 wt% of the indole–in-IL was transferred to toluene. Thus, both extractions of nitrogen and sulphur model compounds were successfully carried out from model oil and the back-extraction of these compounds from the ionic liquids to toluene demonstrated the proved the concept of the regeneration point of view.展开更多
Atmosphere is the basic environmental element on which human beings depend for survival and development,and its environmental quality is directly related to sustainable socio-economic development.China is currently in...Atmosphere is the basic environmental element on which human beings depend for survival and development,and its environmental quality is directly related to sustainable socio-economic development.China is currently in a period of accelerated urbanization,accompanied by industrialization and urbanization bringing environmental pollution problems more and more prominent.Therefore,it is particularly important to strengthen the management of atmospheric quality and improve the level of atmospheric environment.To this end,the spatial and temporal distribution characteristics of AQI and six types of air pollutants in eight prefecture-level cities were analysed and studied using the month-by-month air quality monitoring data of Sichuan Province from 2017 to 2021.The results show that:(1)according to the Ambient Air Quality Standards,Chengdu,Mianyang,Zigong,Luzhou and Deyang do not meet the concentration limits of PM_(2.5),Zigong and Suining do not meet the concentration limits of PM_(10),Chengdu does not meet the concentration limits of NO_(2),and all eight cities meet the concentration limits of NO_(2)and SO_(2).(2)The seasonal concentration changes of PM_(2.5),PM_(10)and NO_(2)have the same characteristics,showing that they are winter>spring>autumn>summer.The seasonal concentration changes of CO are winter>autumn>spring>summer;the seasonal concentration changes of SO_(2)are winter>spring>summer>autumn;the seasonal concentration changes of O_(3)are summer>spring>autumn>winter.展开更多
The presence of temperature inversions (TI), concentration of air pollutants (AP) and meteorological variables (MV) affect the welfare of the population, creating public health problems (acute respiratory diseases ARD...The presence of temperature inversions (TI), concentration of air pollutants (AP) and meteorological variables (MV) affect the welfare of the population, creating public health problems (acute respiratory diseases ARDs, among others). The Guadalajara Metropolitan Zone (GMZ) experiences high levels of air pollution, which associated with the presence of temperature inversions and meteorological variations is conducive to the incidence of ARDs in children. The aim of this work is to evaluate the TI, MV, AP and their influence on the ARDs in children under five years in the GMZ from 2003 to 2007. In this period, the moderate and strong TI are the most frequent presenting from November to May. The AP shows a variable behavior during the year and between years, with the highest concentration of particles less than 10 microns (PM10), followed by ozone (O3), nitrogen dioxide (NO2), nitrogen oxides (NOX), carbon monoxide (CO) and sulfur dioxide (SO2), the most affected areas are the southeast of the GMZ. Annual arithmetic mean is 213,510 ± 41,209 ARDs consultations. The most important diseases are acute respiratory infections (98.0%), followed by pneumonia and bronchopneumonia (1.1%), asthma and status asthmaticus (0.5%) and streptococcal pharyngitis and tonsillitis (0.4%). Months with most inquiries were from October to March, mainly in the southeast, south and center of the city, coinciding with high levels of AP. Statistical analysis shows that the TI have significant correlation with ARDs in three years, temperature (Temp) in two, relative humidity (RH) in two, wind speed (WS) in three, wind direction (WD) in two, while that air pollutants NOX and NO2 showed significant correlation with ARDs throughout the period. CO and SO2 showed significance in two years, while the PM10 and O3 in one.展开更多
BACKGROUND Gastroesophageal reflux disease(GERD)is a highly prevalent disease of the upper gastrointestinal tract,and it is associated with environmental and lifestyle habits.Due to an increasing interest in the envir...BACKGROUND Gastroesophageal reflux disease(GERD)is a highly prevalent disease of the upper gastrointestinal tract,and it is associated with environmental and lifestyle habits.Due to an increasing interest in the environment,several groups are studying the effects of meteorological factors and air pollutants(MFAPs)on disease development.AIM To identify MFAPs effect on GERD-related medical utilization.METHODS Data on GERD-related medical utilization from 2002 to 2017 were obtained from the National Health Insurance Service of Korea,while those on MFAPs were obtained from eight metropolitan areas and merged.In total,20071900 instances of GERD-related medical utilizations were identified,and 200000 MFAPs were randomly selected from the eight metropolitan areas.Data were analyzed using a multivariable generalized additive Poisson regression model to control for time trends,seasonality,and day of the week.RESULTS Five MFAPs were selected for the prediction model.GERD-related medical utilization increased with the levels of particulate matter with a diameter≤2.5μm(PM2.5)and carbon monoxide(CO).S-shaped and inverted U-shaped changes were observed in average temperature and air pollutants,respectively.The time lag of each variable was significant around nine days after exposure.CONCLUSION Using five MFAPs,the final model significantly predicted GERD-related medical utilization.In particular,PM2.5 and CO were identified as risk or aggravating factors for GERD.展开更多
The world maritime transportation is suffering a large increase in recent years and as a result of this increased on global trade, there is a consequent increase in waterway transportation and demand for fossil fuels,...The world maritime transportation is suffering a large increase in recent years and as a result of this increased on global trade, there is a consequent increase in waterway transportation and demand for fossil fuels, resulting in emissions of air pollutants. Consequently, the impact of transport emissions on climate change was put on the list of priorities. It has a high fuel demand as a result of continuous use of main engines for propulsion, electricity and heat production. The highest exposure levels of air pollution are found in ports and near them because most of the world fleet is positioned in these areas. The port of Rio de Janeiro city, in the Southeast Brazilian coastal, is inserted in the Guanabara Bay (GB), where the breezes recirculate pollutants in Metropolitan Region of Rio de Janeiro (MRRJ). Therefore, the aim of this research was to use the Brazilian Regional Atmospheric Modeling System (BRAMS) to generate the wind fields in the MRRJ and to calculate the trajectories of pollutants emitted on GB related to the waterway transportation, using a 3D kinematic trajectories model. Results demonstrated that for the periods analysed, the Central and west areas in the coastal region of the Rio de Janeiro city were the local most affected in the summer. In winter the trajectories reached the cities of the Rio de Janeiro and Duque de Caxias. Both in summer and winter, the trajectories followed towards the South Atlantic Ocean in the morning. Conclusions about this study show the need of decision-making process for better management of waterway transportation sector, improving the harmful effects on air quality in cities located in coastal regions.展开更多
During the last decades, air pollution has become a serious environmental hazard. Its impact on public health and safety, as well as on the ecosystem, has been dramatic. Forecasting the levels of air pollution to main...During the last decades, air pollution has become a serious environmental hazard. Its impact on public health and safety, as well as on the ecosystem, has been dramatic. Forecasting the levels of air pollution to maintain the climatic conditions and environmental protection becomes crucial for government authorities to develop strategies for the prevention of pollution. This study aims to evaluate the atmospheric air pollution of the city of Zahleh located in the geographic zone of Bekaa. The study aims to determine a relationship between variations in ambient particulate concentrations during a short time. The data was collected from June 2017 to June 2018. In order to predict the Air Quality Index (AQI), Naïve, Exponential Smoothing, TBATS (a forecasting method to model time series data), and Seasonal Autoregressive Integrated Moving Average (SARIMA) models were implemented. The performance of these models for predicting air quality is measured using the Mean Absolute Error (MAE), the Root Mean Square Error (RMSE), and the Relative Error (RE). SARIMA model is the most accurate in prediction of AQI (RMSE = 38.04, MAE = 22.52 and RE = 0.16). The results reveal that SARIMA can be applied to cities like Zahleh to assess the level of air pollution and to prevent harmful impacts on health. Furthermore, the authorities responsible for controlling the air quality may use this model to measure the level of air pollution in the nearest future and establish a mechanism to identify the high peaks of air pollution.展开更多
Traffic-related air pollution is an alarming source of pollutants exposure and consequently to the development of several adverse health effects. Otherwise, green spaces are reported to improve health status. Although...Traffic-related air pollution is an alarming source of pollutants exposure and consequently to the development of several adverse health effects. Otherwise, green spaces are reported to improve health status. Although, in an urban scenario most of these areas are located near air pollutants sources, as vehicle fleet. Thus, the aim of the present study was to determine, during one year, the levels of nitrogen dioxide (NO2) and ozone (O3) in the main parks from Porto Alegre—Brazil. This study focused on three urban parks: Germania, Moinhos de Vento and Marinha do Brasil Park. Nitrogen dioxide and ozone measurements were accessed by passive monitoring in four campaigns including all seasons and performed at distances of 0 m, 15 m, 30 m, 45 m, 60 m and 75 m from the main road at each park. NO2 and O3 concentration among the parks was not different (p > 0.05), as well as the mean concentration of NO2 and O3 of all parks in the six sites did not differ (p > 0.05). However, season 1 and 3 showed increased NO2 and O3 concentration. Temperature were decreased in season 1 and 3 (p p > 0.05). Traffic flow was higher in Moinhos de Vento Park and Marinha do Brasil Park compared to Germania Park (p 2 and O3 concentration in urban parks from Porto Alegre.展开更多
This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle ...This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle air pollutants in downtown Beijing in 2021 was established,and the impact of these emissions on air quality was simulated and quantified,and different emission reduction control scenarios were proposed to evaluate their environmental improvement effects and explore measures to mitigate the impact of pollution emissions.The results show that the high traffic flow and the structure of the motor vehicle emissions in downtown Beijing are the main causes of severe motor vehicle pollution.Monitoring data shows that traffic flow in central Beijing is dominated by small passenger vehicles,while the vehicle mix is better than in other regions,with 72.0%of vehicles meeting"National V"or higher emission standards.However,to achieve higher air quality goals,further reducing vehicle emissions is necessary.Based on dynamic traffic flow,the average daily emissions of nitrogen oxides(NOX),particulate matters(PM_(2.5))and volatile organic compounds(VOC)from motor vehicles in central Beijing are 17.7 tons,0.6 tons and 14.0 tons,respectively,accounting for 23.0%of the city’s average daily motor vehicle emissions.If a zero-emission zone for motor vehicles were implemented in central Beijing,the annual average emission level of pollutants will be reduced by 10.4%to 21.0%.The designation of ultra-low emission zones for motor vehicles could be effective in improving the air quality in the center of Beijing.展开更多
Red mud,as a solid waste produced during the alumina production,can cause severe ecoenvironmental pollution and health risks to human.Therefore,the resourcing of this type of solid waste is an effective way for the su...Red mud,as a solid waste produced during the alumina production,can cause severe ecoenvironmental pollution and health risks to human.Therefore,the resourcing of this type of solid waste is an effective way for the sustainable development.This paper reviews the recent progress on red mud-based catalysts for the removal of typical air pollutants,such as the catalytic reduction of nitrogen oxides(NO_(x))by NH_(3)(NH_(3)-SCR)and the catalytic oxidation of CO and volatile organic compounds(VOCs).The factors influencing the catalytic performance and the structure–activity relationship have been discussed.Future prospects and directions for the development of such catalysts are also proposed.This review would benefit for the high value-added utilizations of red mud in mitigating atmospheric pollutions.展开更多
A variety of methods based on air quality models,including tracer methods,the bruteforce method(BFM),decoupled direct method(DDM),high-order decoupled direct method(HDDM),response surface models(RSMs)and so on forth,h...A variety of methods based on air quality models,including tracer methods,the bruteforce method(BFM),decoupled direct method(DDM),high-order decoupled direct method(HDDM),response surface models(RSMs)and so on forth,have been widely used to study the transport of air pollutants.These methods have good applicability for the transport of air pollutants with simple formation mechanisms.However,differences in research conclusions on secondary pollutants with obvious nonlinear characteristics have been reported.For example,the tracer method is suitable for the study of simpli?ed scenarios,while HDDM and RSMs are more suitable for the study for nonlinear pollutants.Multiple observation techniques,including conventional air pollutant observation,lidar observation,air sounding balloons,vehicle-mounted and ship-borne technology,aerial surveys,and remote sensing observations,have been utilized to investigate air pollutant transport characteristics with time resolution as high as 1 sec.In addition,based on a multi-regional input-output model combined with emission inventories,the transfer of air pollutant emissions can be evaluated and applied to study the air pollutant transport characteristics.Observational technologies have advantages in temporal resolution and accuracy,while modeling technologies are more?exible in spatial resolution and research plan setting.In order to accurately quantify the transport characteristics of pollutants,it is necessary to develop a research method for interactive veri?cation of observation and simulation.Quantitative evaluation of the transport of air pollutants from different angles can provide a scienti?c basis for regional joint prevention and control.展开更多
Over the past decade,the emission standards and fuel standards in Beijing have been upgraded twice,and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles.Through the f...Over the past decade,the emission standards and fuel standards in Beijing have been upgraded twice,and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles.Through the formulation and implementation of these policies,the emissions of carbon monoxide(CO),volatile organic compounds(VOCs),nitrogen oxides(NO_(x)),and fine particulate matter(PM_(2.5))in 2019 were 147.9,25.3,43.4,and 0.91 kton in Beijing,respectively.The emission factor method was adopted to better understand the emissions characteristics of primary air pollutants from combustion engine vehicles and to improve pollution control.In combination with the air quality improvement goals and the status of social and economic development during the 14th Five-Year Plan period in Beijing,different vehicle pollution control scenarios were established,and emissions reductions were projected.The results show that the emissions of four air pollutants(CO,VOCs,NO_(x),and PM_(2.5))fromvehicles in Beijing decreased by an average of 68% in 2019,compared to their levels in 2009.The contribution of NOx emissions from diesel vehicles increased from 35% in 2009 to 56% in 2019,which indicated that clean and energy-saving diesel vehicle fleets should be further improved.Electric vehicle adoption could be an important measure to reduce pollutant emissions.With the further upgrading of vehicle structure and the adoption of electric vehicles,it is expected that the total emissions of the four vehicle pollutants can be reduced by 20%-41% by the end of the 14th Five-Year Plan period.展开更多
Air pollutant concentration is a function of emission rates and meteorology.To accurately evaluate the effect of control measures,the meteorological covariate must be corrected from the observations.This study quantif...Air pollutant concentration is a function of emission rates and meteorology.To accurately evaluate the effect of control measures,the meteorological covariate must be corrected from the observations.This study quantified the impacts of emission abatement and meteorological condition on the interannual variations of SO_(2),NO_(2),CO,O_(3),PM_(10) and PM_(2.5) concentrations in 31 major Chinese cities using an optimized machine learning-based meteorological normalization technique.Overall,the annual average concentrations of SO_(2),NO_(2),CO,PM_(10)and PM_(2.5)were reduced by 86%,51%,99%,86% and 88%from 2015 to 2020,respectively,in the studied cities,attributable to their emission reductions.However,the concentration of O_(3) was found with no significant decrease with the reduction of precursors.Emission abatement notably improved air quality between 2015 and 2018.Such a decline in emissions tended to progressively slow down since 2018.Overall,the meteorological conditions in 2016–2017 and 2018–2019 were unfavorable for a better air quality,while it became favorable in 2020–2021.Specifically,emission abatement in 2021 further lowered the concentrations of SO_(2),NO_(2),CO,and PM_(2.5),while the emission of PM_(10) increased.And changes in precursors emissions worsened O_(3) air quality.To meet the demand of improving air quality,more aggressive abatement measures need to be formulated to synergistically reduce NOx,volatile organic compounds,and coarse particles.展开更多
A numerical physio-chemical model of the NO_(x)-O_(3) photochemical cycle in the near-wake region of an isolated residential/office building has been presented in this study.The investigation delves into the dispersio...A numerical physio-chemical model of the NO_(x)-O_(3) photochemical cycle in the near-wake region of an isolated residential/office building has been presented in this study.The investigation delves into the dispersion of reactive air pollutants through the lens of fluid phenomenology and its impact on chemical reactivity,formation,transport,deposition,and removal.Computational fluid dynamics(CFD)simulations were conducted for the ground-point-source(GES)and roof-pointsource(RES)scenarios.Results show that the Damköhler number(Da),which quantifies pollutants’physio-chemical timescales,displays a strong inverse proportionality with the magnitude and spread of NO–increasing Da reduces human exposure to the toxic NO and NO_(2) substantially.When different wind directions were considered,the dispersion range of NO exhibited varying shrinking directions as Da increased.Furthermore,as Da increases,the concentration ratio KNO_(2)/KNO_(x),which quantifies the production of NO_(2) resulting from NO depletion,forms sharp high-low gradients near emission sources.For GES,the dispersion pattern is governed by the fluid’s phenomenological features.For RES,the intoxicated area emanates from the building’s leading-edge,with the lack of shielding inhibiting pollutant interactions in the near-wake,resulting in scant physio-chemical coupling.The NO_(2)/NO_(x) distribution follows a self-similar,stratified pattern,exhibiting consistent layering gradients and attributing to the natural deposition of the already-reacted pollutants rather than in-situ reactions.In the end,building design guidelines have been proposed to reduce pedestrian and resident exposure to NO_(x)-O_(3).展开更多
Maintaining a steady power supply requires accurate forecasting of solar irradiance,since clean energy resources do not provide steady power.The existing forecasting studies have examined the limited effects of weathe...Maintaining a steady power supply requires accurate forecasting of solar irradiance,since clean energy resources do not provide steady power.The existing forecasting studies have examined the limited effects of weather conditions on solar radiation such as temperature and precipitation utilizing convolutional neural network(CNN),but no comprehensive study has been conducted on concentrations of air pollutants along with weather conditions.This paper proposes a hybrid approach based on deep learning,expanding the feature set by adding new air pollution concentrations,and ranking these features to select and reduce their size to improve efficiency.In order to improve the accuracy of feature selection,a maximum-dependency and minimum-redundancy(mRMR)criterion is applied to the constructed feature space to identify and rank the features.The combination of air pollution data with weather conditions data has enabled the prediction of solar irradiance with a higher accuracy.An evaluation of the proposed approach is conducted in Istanbul over 12 months for 43791 discrete times,with the main purpose of analyzing air data,including particular matter(PM10 and PM25),carbon monoxide(CO),nitric oxide(NOX),nitrogen dioxide(NO_(2)),ozone(O₃),sulfur dioxide(SO_(2))using a CNN,a long short-term memory network(LSTM),and MRMR feature extraction.Compared with the benchmark models with root mean square error(RMSE)results of 76.2,60.3,41.3,32.4,there is a significant improvement with the RMSE result of 5.536.This hybrid model presented here offers high prediction accuracy,a wider feature set,and a novel approach based on air concentrations combined with weather conditions for solar irradiance prediction.展开更多
The impact of global climate change and air pollution on mental health has become a crucial public health issue.Increased public awareness of health,advancements in medical diagnosis and treatment,the way media outlet...The impact of global climate change and air pollution on mental health has become a crucial public health issue.Increased public awareness of health,advancements in medical diagnosis and treatment,the way media outlets report environmental changes and the variation in social resources affect psychological responses and adaptation methods to climate change and air pollution.In the context of climate change,extreme weather events seriously disrupt people's living environments,and unstable educational environments lead to an increase in mental health issues for students.Air pollution affects students'mental health by increasing the incidence of diseases while decreasing contact with nature,leading to problems such as anxiety,depression,and decreased cognitive function.We call for joint efforts to reduce pollutant emissions at the source,improve energy structures,strengthen environmental monitoring and governance,increase attention to the mental health issues of students,and help student groups build resilience;by establishing public policies,enhancing social support and adjusting lifestyles and habits,we can help students cope with the constantly changing environment and maintain a good level of mental health.Through these comprehensive measures,we can more effectively address the challenges of global climate change and air pollution and promote the achievement of the United Nations Sustainable Development Goals.展开更多
Nairobi County experiences rapid industrialization and urbanization that contributes to the deteriorating state of air quality, posing a potential health risk to its growing population. Currently, in Nairobi County, m...Nairobi County experiences rapid industrialization and urbanization that contributes to the deteriorating state of air quality, posing a potential health risk to its growing population. Currently, in Nairobi County, most air quality monitoring stations use low-cost, inaccurate monitors prone to defects. The study’s objective was to map Nairobi County’s air quality using freely available remotely sensed imagery. The Air Pollution Index (API) formula was used to characterize the air quality from cloud-free Landsat satellite images i.e., Landsat 5 TM, Landsat 7 ETM+, and Landsat 8 OLI from Google Earth Engine. The API values were computed based on vegetation indices namely NDVI, TVI, DVI, and the SWIR1 and NIR bands on the QGIS platform. Qualitative accuracy assessment was done using sample points drawn from residential, industrial, green spaces, and traffic hotspot categories, based on a passive-random sampling technique. In this study, Landsat 5 API imagery for 2010 provided a reliable representation of local conditions but indicated significant pollution in green spaces, with recorded values ranging from -143 to 334. The study found that Landsat 7 API imagery in 2002 showed expected results with the range of values being -55 to 287, while Landsat 8 indicated high pollution levels in Nairobi. The results emphasized the importance of air quality factors in API calibration and the unmatched spatial coverage of satellite observations over ground-based monitoring techniques. The study recommends the recalibration of the API formula for characteristic regions, exploring newer satellite sensors like those onboard Landsat 9 and Sentinel 2, and involving key stakeholders in a discourse to develop a suitable Kenyan air quality index.展开更多
The thermal internal boundary layer(TIBL) is associated with coastal pollution dispersion,which can result in high concentrations of air pollutants near the surface of the Earth. In this study, boundary layer height d...The thermal internal boundary layer(TIBL) is associated with coastal pollution dispersion,which can result in high concentrations of air pollutants near the surface of the Earth. In this study, boundary layer height data which were obtained using a ceilometer were used to assess the effect of the TIBL on atmospheric pollutants in Qinhuangdao, a coastal city in North China.A TIBL formed on 33% of summer days. When a TIBL formed, the sunshine duration was 2.4 hr longer, the wind speed was higher, the wind direction reflected a typical sea breeze, and the boundary layer height was lower from 9:00 LT to 20:00 LT compared to days without a TIBL. If no TIBL formed, the average concentrations of PM_(2.5) and PM_(10) decreased with increasing boundary layer height. However, when a TIBL was observed, the average concentrations of PM_(2.5) and PM_(10) increased with increasing boundary layer height. Because the air from the sea is clean, PM_(2.5) and PM_(10) concentrations reached minimums in the daytime at 16:00 LT. After16:00 LT, the PM_(2.5) and PM_(10) concentrations increased rapidly on days when a TIBL formed,which indicated that the TIBL leads to the rapid accumulation of atmospheric pollutants in the evening. Therefore, the maximum concentrations of particulate matters were larger when a TIBL formed compared to when no TIBL was present during the night. These results indicate that it is suitable for outdoor activities in the daytime on days with a TIBL in coastal cities.展开更多
Indoor air pollutants impact human health,comfort and productivity.The method of photocatalysis has been applied mainly in flow reactors and little information is available on indoor air pollutant removal in airtight ...Indoor air pollutants impact human health,comfort and productivity.The method of photocatalysis has been applied mainly in flow reactors and little information is available on indoor air pollutant removal in airtight reactors.In the paper,experiments were carried out to remove formaldehyde(HCHO),ammonia(NH_3) and volatile organic compounds(VOCs)in the airtight and ventilated chambers.Results demonstrated that 90.4%of HCHO,92.3%of NH_3 and 57.9%of VOCs were removed in the amine adsorption process,while 67.5% (hereinbefore,these are the mass fraction)of HCHO,60.0%of NH_3,and 61.2%of VOCs were removed in the photocatalytic process.However,ozone-assisted photocatalytic process showed great potential to degrade indoor air pollutants in the ventilated chamber.Factors and mechanisms of the photocatalytic degradation of HCHO, NH_3 and VOCs were also discussed.展开更多
基金the funding provided by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(NRF-2020R1A2C1006506).
文摘Exposure to air pollutants such as PM_(10),PM_(2.5),PM_(0.1),O_(3),CO,NO2,and SO_(2),and biological pollutants are important factors causing the evolution and furtherance of obstructive lung diseases(OLD),including asthma and chronic obstructive pulmonary disease(COPD).Asthma is the most frequent chronic inflammatory airway disease,characterized by breathlessness,wheezing,chest tightness,and cough,together with the presence of exaggerated expiratory airflow fluctuation that varies over time.COPD is a heterogeneous lung condition characterized by chronic respiratory symptoms such as dyspnea,cough,expectoration,and/or exacerbations due to abnormalities of the airways and/or alveoli that cause persistent,often progressive,airflow obstruction.Understanding the molecular mechanisms and cellular processes based on the development of OLD on exposure to air pollutants will provide insights into the solution of pathogenesis,prevention,and treatment of these conditions.The molecular mechanisms and cellular process involved in signal transduction pathway plays a role in the binding of extracellular signaling molecules and ligands to receptors placed on the cell surface or on the inner side cell that trigger inflammation that occurs,especially when something important enters the cell to bring into a cascade response.This binding then alters the cell metabolism,shape,and gene expression in the airway.This review aimed to reveal the effect of air pollutants on the molecular mechanisms and cellular processes involved in the signal transduction pathways in OLD.
文摘Emissions of air pollutants and greenhouse gases into the atmosphere in Antarctica from power plants with diesel generators(the main sources of energy at Antarctic research stations and the main stationary sources of anthropogenic emissions in the Antarctic)were assessed.A bottom-up approach was used to compile an emission inventory for the Antarctic.This involved estimating emissions at various spatial levels by sequentially aggregating estimate emissions from point emission sources.This is the first time this approach has been proposed and used.Emissions of CO2,NOx,particulate matter(PM10),and CO in the modern period were estimated at the research station,geographic region,natural domain,biogeographic region,continent section,and whole continent scales.Yearly emissions are presented here,but the approach allows emissions at different averaging periods to be estimated.This means mean or maximum yearly,monthly,daily,or hourly emissions can be estimated.The estimates could be used to model pollutant transmission and dispersion,assess the impacts of pollutants,and develop emission forecasts for various scenarios.
文摘Removal of air pollutants, such as nitrogen and sulphur containing compounds from a model oil (dodecane) was studied. An ionic liquid (1-ethyl-3-methylimidazolium chloride [C2mim] [Cl]) was used as an extractant. Liquid-liquid extraction by using 1-ethyl-3-methylimidazolium chloride [C2mim] [Cl] was found to be a very promising method for the removal of N- and S-compounds. This was evaluated by using a model oil (dodecane) with indole as a neutral nitrogen compound and pyridine as a basic nitrogen compound. Dibenzothiophene (DBT) was used as a sulphur compound. An extraction capacity of up to 90 wt% was achieved for the model oil containing pyridine, while only 76 wt% of indole in the oil was extracted. The extraction capacity of a model sulphur compound DBT was found to be up to 99 wt%. Regeneration of the spent ionic liquid was carried out with toluene back-extraction. A 1:1 toluene-to-IL wt ratio was performed at room temperature. It was observed that, for the spent ionic liquid containing DBT as a model compound more than 85 wt% (corresponding 3852 mg/kg) could be removed from the oil. After the second regeneration cycle, 86 wt% of the DBT was recovered from the ionic liquid to toluene. In the case of indole as the nitrogen containing species, more than 99 wt%, (corresponding to 2993 mg/kg) of the original indole was transferred from the model oil to the ionic liquid. After the first-regeneration cycle of the spent ionic liquid, 54 wt% of the indole–in-IL was transferred to toluene. Thus, both extractions of nitrogen and sulphur model compounds were successfully carried out from model oil and the back-extraction of these compounds from the ionic liquids to toluene demonstrated the proved the concept of the regeneration point of view.
基金Supported by Physical and Chemical Characteristics and Source Analysis of Atmospheric Particulate Matter in Lhasa,Tibet(21677116)National Natural Science Foundation of China,National Key Research&Development Program of China(2019YFC1904101)。
文摘Atmosphere is the basic environmental element on which human beings depend for survival and development,and its environmental quality is directly related to sustainable socio-economic development.China is currently in a period of accelerated urbanization,accompanied by industrialization and urbanization bringing environmental pollution problems more and more prominent.Therefore,it is particularly important to strengthen the management of atmospheric quality and improve the level of atmospheric environment.To this end,the spatial and temporal distribution characteristics of AQI and six types of air pollutants in eight prefecture-level cities were analysed and studied using the month-by-month air quality monitoring data of Sichuan Province from 2017 to 2021.The results show that:(1)according to the Ambient Air Quality Standards,Chengdu,Mianyang,Zigong,Luzhou and Deyang do not meet the concentration limits of PM_(2.5),Zigong and Suining do not meet the concentration limits of PM_(10),Chengdu does not meet the concentration limits of NO_(2),and all eight cities meet the concentration limits of NO_(2)and SO_(2).(2)The seasonal concentration changes of PM_(2.5),PM_(10)and NO_(2)have the same characteristics,showing that they are winter>spring>autumn>summer.The seasonal concentration changes of CO are winter>autumn>spring>summer;the seasonal concentration changes of SO_(2)are winter>spring>summer>autumn;the seasonal concentration changes of O_(3)are summer>spring>autumn>winter.
文摘The presence of temperature inversions (TI), concentration of air pollutants (AP) and meteorological variables (MV) affect the welfare of the population, creating public health problems (acute respiratory diseases ARDs, among others). The Guadalajara Metropolitan Zone (GMZ) experiences high levels of air pollution, which associated with the presence of temperature inversions and meteorological variations is conducive to the incidence of ARDs in children. The aim of this work is to evaluate the TI, MV, AP and their influence on the ARDs in children under five years in the GMZ from 2003 to 2007. In this period, the moderate and strong TI are the most frequent presenting from November to May. The AP shows a variable behavior during the year and between years, with the highest concentration of particles less than 10 microns (PM10), followed by ozone (O3), nitrogen dioxide (NO2), nitrogen oxides (NOX), carbon monoxide (CO) and sulfur dioxide (SO2), the most affected areas are the southeast of the GMZ. Annual arithmetic mean is 213,510 ± 41,209 ARDs consultations. The most important diseases are acute respiratory infections (98.0%), followed by pneumonia and bronchopneumonia (1.1%), asthma and status asthmaticus (0.5%) and streptococcal pharyngitis and tonsillitis (0.4%). Months with most inquiries were from October to March, mainly in the southeast, south and center of the city, coinciding with high levels of AP. Statistical analysis shows that the TI have significant correlation with ARDs in three years, temperature (Temp) in two, relative humidity (RH) in two, wind speed (WS) in three, wind direction (WD) in two, while that air pollutants NOX and NO2 showed significant correlation with ARDs throughout the period. CO and SO2 showed significance in two years, while the PM10 and O3 in one.
基金Gachon University Gil Medical Center,No.FRD2018-17 and No.FRD2019-11.
文摘BACKGROUND Gastroesophageal reflux disease(GERD)is a highly prevalent disease of the upper gastrointestinal tract,and it is associated with environmental and lifestyle habits.Due to an increasing interest in the environment,several groups are studying the effects of meteorological factors and air pollutants(MFAPs)on disease development.AIM To identify MFAPs effect on GERD-related medical utilization.METHODS Data on GERD-related medical utilization from 2002 to 2017 were obtained from the National Health Insurance Service of Korea,while those on MFAPs were obtained from eight metropolitan areas and merged.In total,20071900 instances of GERD-related medical utilizations were identified,and 200000 MFAPs were randomly selected from the eight metropolitan areas.Data were analyzed using a multivariable generalized additive Poisson regression model to control for time trends,seasonality,and day of the week.RESULTS Five MFAPs were selected for the prediction model.GERD-related medical utilization increased with the levels of particulate matter with a diameter≤2.5μm(PM2.5)and carbon monoxide(CO).S-shaped and inverted U-shaped changes were observed in average temperature and air pollutants,respectively.The time lag of each variable was significant around nine days after exposure.CONCLUSION Using five MFAPs,the final model significantly predicted GERD-related medical utilization.In particular,PM2.5 and CO were identified as risk or aggravating factors for GERD.
文摘The world maritime transportation is suffering a large increase in recent years and as a result of this increased on global trade, there is a consequent increase in waterway transportation and demand for fossil fuels, resulting in emissions of air pollutants. Consequently, the impact of transport emissions on climate change was put on the list of priorities. It has a high fuel demand as a result of continuous use of main engines for propulsion, electricity and heat production. The highest exposure levels of air pollution are found in ports and near them because most of the world fleet is positioned in these areas. The port of Rio de Janeiro city, in the Southeast Brazilian coastal, is inserted in the Guanabara Bay (GB), where the breezes recirculate pollutants in Metropolitan Region of Rio de Janeiro (MRRJ). Therefore, the aim of this research was to use the Brazilian Regional Atmospheric Modeling System (BRAMS) to generate the wind fields in the MRRJ and to calculate the trajectories of pollutants emitted on GB related to the waterway transportation, using a 3D kinematic trajectories model. Results demonstrated that for the periods analysed, the Central and west areas in the coastal region of the Rio de Janeiro city were the local most affected in the summer. In winter the trajectories reached the cities of the Rio de Janeiro and Duque de Caxias. Both in summer and winter, the trajectories followed towards the South Atlantic Ocean in the morning. Conclusions about this study show the need of decision-making process for better management of waterway transportation sector, improving the harmful effects on air quality in cities located in coastal regions.
文摘During the last decades, air pollution has become a serious environmental hazard. Its impact on public health and safety, as well as on the ecosystem, has been dramatic. Forecasting the levels of air pollution to maintain the climatic conditions and environmental protection becomes crucial for government authorities to develop strategies for the prevention of pollution. This study aims to evaluate the atmospheric air pollution of the city of Zahleh located in the geographic zone of Bekaa. The study aims to determine a relationship between variations in ambient particulate concentrations during a short time. The data was collected from June 2017 to June 2018. In order to predict the Air Quality Index (AQI), Naïve, Exponential Smoothing, TBATS (a forecasting method to model time series data), and Seasonal Autoregressive Integrated Moving Average (SARIMA) models were implemented. The performance of these models for predicting air quality is measured using the Mean Absolute Error (MAE), the Root Mean Square Error (RMSE), and the Relative Error (RE). SARIMA model is the most accurate in prediction of AQI (RMSE = 38.04, MAE = 22.52 and RE = 0.16). The results reveal that SARIMA can be applied to cities like Zahleh to assess the level of air pollution and to prevent harmful impacts on health. Furthermore, the authorities responsible for controlling the air quality may use this model to measure the level of air pollution in the nearest future and establish a mechanism to identify the high peaks of air pollution.
基金support funding from Fundacao de Amparo a Pesquisa do Estado do Rio Grande do Sul(FAPERGS).
文摘Traffic-related air pollution is an alarming source of pollutants exposure and consequently to the development of several adverse health effects. Otherwise, green spaces are reported to improve health status. Although, in an urban scenario most of these areas are located near air pollutants sources, as vehicle fleet. Thus, the aim of the present study was to determine, during one year, the levels of nitrogen dioxide (NO2) and ozone (O3) in the main parks from Porto Alegre—Brazil. This study focused on three urban parks: Germania, Moinhos de Vento and Marinha do Brasil Park. Nitrogen dioxide and ozone measurements were accessed by passive monitoring in four campaigns including all seasons and performed at distances of 0 m, 15 m, 30 m, 45 m, 60 m and 75 m from the main road at each park. NO2 and O3 concentration among the parks was not different (p > 0.05), as well as the mean concentration of NO2 and O3 of all parks in the six sites did not differ (p > 0.05). However, season 1 and 3 showed increased NO2 and O3 concentration. Temperature were decreased in season 1 and 3 (p p > 0.05). Traffic flow was higher in Moinhos de Vento Park and Marinha do Brasil Park compared to Germania Park (p 2 and O3 concentration in urban parks from Porto Alegre.
基金supported by the National Key Research and Development Program of China (No.2022YFC3800403)the Foundation of Beijing Municipal Research Institute of EcoEnvironmental Protection (No.Y2022-007)。
文摘This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle air pollutants in downtown Beijing in 2021 was established,and the impact of these emissions on air quality was simulated and quantified,and different emission reduction control scenarios were proposed to evaluate their environmental improvement effects and explore measures to mitigate the impact of pollution emissions.The results show that the high traffic flow and the structure of the motor vehicle emissions in downtown Beijing are the main causes of severe motor vehicle pollution.Monitoring data shows that traffic flow in central Beijing is dominated by small passenger vehicles,while the vehicle mix is better than in other regions,with 72.0%of vehicles meeting"National V"or higher emission standards.However,to achieve higher air quality goals,further reducing vehicle emissions is necessary.Based on dynamic traffic flow,the average daily emissions of nitrogen oxides(NOX),particulate matters(PM_(2.5))and volatile organic compounds(VOC)from motor vehicles in central Beijing are 17.7 tons,0.6 tons and 14.0 tons,respectively,accounting for 23.0%of the city’s average daily motor vehicle emissions.If a zero-emission zone for motor vehicles were implemented in central Beijing,the annual average emission level of pollutants will be reduced by 10.4%to 21.0%.The designation of ultra-low emission zones for motor vehicles could be effective in improving the air quality in the center of Beijing.
基金supported by the National Natural Science Foundation of China(Nos.21876009,21677008)National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2019A18)the Fundamental Research Funds for the Central Universities(Nos.JD2110,PY2103).
文摘Red mud,as a solid waste produced during the alumina production,can cause severe ecoenvironmental pollution and health risks to human.Therefore,the resourcing of this type of solid waste is an effective way for the sustainable development.This paper reviews the recent progress on red mud-based catalysts for the removal of typical air pollutants,such as the catalytic reduction of nitrogen oxides(NO_(x))by NH_(3)(NH_(3)-SCR)and the catalytic oxidation of CO and volatile organic compounds(VOCs).The factors influencing the catalytic performance and the structure–activity relationship have been discussed.Future prospects and directions for the development of such catalysts are also proposed.This review would benefit for the high value-added utilizations of red mud in mitigating atmospheric pollutions.
基金supported by the National Key R&D Program of China(No.2018YFC0213200)。
文摘A variety of methods based on air quality models,including tracer methods,the bruteforce method(BFM),decoupled direct method(DDM),high-order decoupled direct method(HDDM),response surface models(RSMs)and so on forth,have been widely used to study the transport of air pollutants.These methods have good applicability for the transport of air pollutants with simple formation mechanisms.However,differences in research conclusions on secondary pollutants with obvious nonlinear characteristics have been reported.For example,the tracer method is suitable for the study of simpli?ed scenarios,while HDDM and RSMs are more suitable for the study for nonlinear pollutants.Multiple observation techniques,including conventional air pollutant observation,lidar observation,air sounding balloons,vehicle-mounted and ship-borne technology,aerial surveys,and remote sensing observations,have been utilized to investigate air pollutant transport characteristics with time resolution as high as 1 sec.In addition,based on a multi-regional input-output model combined with emission inventories,the transfer of air pollutant emissions can be evaluated and applied to study the air pollutant transport characteristics.Observational technologies have advantages in temporal resolution and accuracy,while modeling technologies are more?exible in spatial resolution and research plan setting.In order to accurately quantify the transport characteristics of pollutants,it is necessary to develop a research method for interactive veri?cation of observation and simulation.Quantitative evaluation of the transport of air pollutants from different angles can provide a scienti?c basis for regional joint prevention and control.
基金supported by the National Natural Science Foundation of China (No.21806012)Beijing Municipal Science and Technology Project (No.Z181100005418015)
文摘Over the past decade,the emission standards and fuel standards in Beijing have been upgraded twice,and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles.Through the formulation and implementation of these policies,the emissions of carbon monoxide(CO),volatile organic compounds(VOCs),nitrogen oxides(NO_(x)),and fine particulate matter(PM_(2.5))in 2019 were 147.9,25.3,43.4,and 0.91 kton in Beijing,respectively.The emission factor method was adopted to better understand the emissions characteristics of primary air pollutants from combustion engine vehicles and to improve pollution control.In combination with the air quality improvement goals and the status of social and economic development during the 14th Five-Year Plan period in Beijing,different vehicle pollution control scenarios were established,and emissions reductions were projected.The results show that the emissions of four air pollutants(CO,VOCs,NO_(x),and PM_(2.5))fromvehicles in Beijing decreased by an average of 68% in 2019,compared to their levels in 2009.The contribution of NOx emissions from diesel vehicles increased from 35% in 2009 to 56% in 2019,which indicated that clean and energy-saving diesel vehicle fleets should be further improved.Electric vehicle adoption could be an important measure to reduce pollutant emissions.With the further upgrading of vehicle structure and the adoption of electric vehicles,it is expected that the total emissions of the four vehicle pollutants can be reduced by 20%-41% by the end of the 14th Five-Year Plan period.
基金supported by the National Key R&D Program of China (Grant No. 2022YFC3703001)the China Postdoctoral Science Foundation (Grant No. 2022T150334)the National Natural Science Foundation of China (Grant Nos. 42177085 & 42177465)。
文摘Air pollutant concentration is a function of emission rates and meteorology.To accurately evaluate the effect of control measures,the meteorological covariate must be corrected from the observations.This study quantified the impacts of emission abatement and meteorological condition on the interannual variations of SO_(2),NO_(2),CO,O_(3),PM_(10) and PM_(2.5) concentrations in 31 major Chinese cities using an optimized machine learning-based meteorological normalization technique.Overall,the annual average concentrations of SO_(2),NO_(2),CO,PM_(10)and PM_(2.5)were reduced by 86%,51%,99%,86% and 88%from 2015 to 2020,respectively,in the studied cities,attributable to their emission reductions.However,the concentration of O_(3) was found with no significant decrease with the reduction of precursors.Emission abatement notably improved air quality between 2015 and 2018.Such a decline in emissions tended to progressively slow down since 2018.Overall,the meteorological conditions in 2016–2017 and 2018–2019 were unfavorable for a better air quality,while it became favorable in 2020–2021.Specifically,emission abatement in 2021 further lowered the concentrations of SO_(2),NO_(2),CO,and PM_(2.5),while the emission of PM_(10) increased.And changes in precursors emissions worsened O_(3) air quality.To meet the demand of improving air quality,more aggressive abatement measures need to be formulated to synergistically reduce NOx,volatile organic compounds,and coarse particles.
基金The work described in this paper was supported by the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.C7064-18G)Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.16207118 and No.16211821)+2 种基金This work is also partly supported by the Natural Science Foundation of Chongqing,China(Project No.cstc2019jcyj-msxmX0565 and No.cstc2020jcyj-msxmX0921)the Key Project of Technological Innovation and Application Development in Chongqing(Project No.cstc2019jscxgksbX0017)the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Project No.311020001).
文摘A numerical physio-chemical model of the NO_(x)-O_(3) photochemical cycle in the near-wake region of an isolated residential/office building has been presented in this study.The investigation delves into the dispersion of reactive air pollutants through the lens of fluid phenomenology and its impact on chemical reactivity,formation,transport,deposition,and removal.Computational fluid dynamics(CFD)simulations were conducted for the ground-point-source(GES)and roof-pointsource(RES)scenarios.Results show that the Damköhler number(Da),which quantifies pollutants’physio-chemical timescales,displays a strong inverse proportionality with the magnitude and spread of NO–increasing Da reduces human exposure to the toxic NO and NO_(2) substantially.When different wind directions were considered,the dispersion range of NO exhibited varying shrinking directions as Da increased.Furthermore,as Da increases,the concentration ratio KNO_(2)/KNO_(x),which quantifies the production of NO_(2) resulting from NO depletion,forms sharp high-low gradients near emission sources.For GES,the dispersion pattern is governed by the fluid’s phenomenological features.For RES,the intoxicated area emanates from the building’s leading-edge,with the lack of shielding inhibiting pollutant interactions in the near-wake,resulting in scant physio-chemical coupling.The NO_(2)/NO_(x) distribution follows a self-similar,stratified pattern,exhibiting consistent layering gradients and attributing to the natural deposition of the already-reacted pollutants rather than in-situ reactions.In the end,building design guidelines have been proposed to reduce pedestrian and resident exposure to NO_(x)-O_(3).
文摘Maintaining a steady power supply requires accurate forecasting of solar irradiance,since clean energy resources do not provide steady power.The existing forecasting studies have examined the limited effects of weather conditions on solar radiation such as temperature and precipitation utilizing convolutional neural network(CNN),but no comprehensive study has been conducted on concentrations of air pollutants along with weather conditions.This paper proposes a hybrid approach based on deep learning,expanding the feature set by adding new air pollution concentrations,and ranking these features to select and reduce their size to improve efficiency.In order to improve the accuracy of feature selection,a maximum-dependency and minimum-redundancy(mRMR)criterion is applied to the constructed feature space to identify and rank the features.The combination of air pollution data with weather conditions data has enabled the prediction of solar irradiance with a higher accuracy.An evaluation of the proposed approach is conducted in Istanbul over 12 months for 43791 discrete times,with the main purpose of analyzing air data,including particular matter(PM10 and PM25),carbon monoxide(CO),nitric oxide(NOX),nitrogen dioxide(NO_(2)),ozone(O₃),sulfur dioxide(SO_(2))using a CNN,a long short-term memory network(LSTM),and MRMR feature extraction.Compared with the benchmark models with root mean square error(RMSE)results of 76.2,60.3,41.3,32.4,there is a significant improvement with the RMSE result of 5.536.This hybrid model presented here offers high prediction accuracy,a wider feature set,and a novel approach based on air concentrations combined with weather conditions for solar irradiance prediction.
文摘The impact of global climate change and air pollution on mental health has become a crucial public health issue.Increased public awareness of health,advancements in medical diagnosis and treatment,the way media outlets report environmental changes and the variation in social resources affect psychological responses and adaptation methods to climate change and air pollution.In the context of climate change,extreme weather events seriously disrupt people's living environments,and unstable educational environments lead to an increase in mental health issues for students.Air pollution affects students'mental health by increasing the incidence of diseases while decreasing contact with nature,leading to problems such as anxiety,depression,and decreased cognitive function.We call for joint efforts to reduce pollutant emissions at the source,improve energy structures,strengthen environmental monitoring and governance,increase attention to the mental health issues of students,and help student groups build resilience;by establishing public policies,enhancing social support and adjusting lifestyles and habits,we can help students cope with the constantly changing environment and maintain a good level of mental health.Through these comprehensive measures,we can more effectively address the challenges of global climate change and air pollution and promote the achievement of the United Nations Sustainable Development Goals.
文摘Nairobi County experiences rapid industrialization and urbanization that contributes to the deteriorating state of air quality, posing a potential health risk to its growing population. Currently, in Nairobi County, most air quality monitoring stations use low-cost, inaccurate monitors prone to defects. The study’s objective was to map Nairobi County’s air quality using freely available remotely sensed imagery. The Air Pollution Index (API) formula was used to characterize the air quality from cloud-free Landsat satellite images i.e., Landsat 5 TM, Landsat 7 ETM+, and Landsat 8 OLI from Google Earth Engine. The API values were computed based on vegetation indices namely NDVI, TVI, DVI, and the SWIR1 and NIR bands on the QGIS platform. Qualitative accuracy assessment was done using sample points drawn from residential, industrial, green spaces, and traffic hotspot categories, based on a passive-random sampling technique. In this study, Landsat 5 API imagery for 2010 provided a reliable representation of local conditions but indicated significant pollution in green spaces, with recorded values ranging from -143 to 334. The study found that Landsat 7 API imagery in 2002 showed expected results with the range of values being -55 to 287, while Landsat 8 indicated high pollution levels in Nairobi. The results emphasized the importance of air quality factors in API calibration and the unmatched spatial coverage of satellite observations over ground-based monitoring techniques. The study recommends the recalibration of the API formula for characteristic regions, exploring newer satellite sensors like those onboard Landsat 9 and Sentinel 2, and involving key stakeholders in a discourse to develop a suitable Kenyan air quality index.
基金supported by the National Key R&D Program of China(No.2017YFC 0210000)the National Natural Science Foundation of China(Nos.41230642 and 41705113)the Beijing Municipal Science and Technology Project(No.ZL171100000617002)
文摘The thermal internal boundary layer(TIBL) is associated with coastal pollution dispersion,which can result in high concentrations of air pollutants near the surface of the Earth. In this study, boundary layer height data which were obtained using a ceilometer were used to assess the effect of the TIBL on atmospheric pollutants in Qinhuangdao, a coastal city in North China.A TIBL formed on 33% of summer days. When a TIBL formed, the sunshine duration was 2.4 hr longer, the wind speed was higher, the wind direction reflected a typical sea breeze, and the boundary layer height was lower from 9:00 LT to 20:00 LT compared to days without a TIBL. If no TIBL formed, the average concentrations of PM_(2.5) and PM_(10) decreased with increasing boundary layer height. However, when a TIBL was observed, the average concentrations of PM_(2.5) and PM_(10) increased with increasing boundary layer height. Because the air from the sea is clean, PM_(2.5) and PM_(10) concentrations reached minimums in the daytime at 16:00 LT. After16:00 LT, the PM_(2.5) and PM_(10) concentrations increased rapidly on days when a TIBL formed,which indicated that the TIBL leads to the rapid accumulation of atmospheric pollutants in the evening. Therefore, the maximum concentrations of particulate matters were larger when a TIBL formed compared to when no TIBL was present during the night. These results indicate that it is suitable for outdoor activities in the daytime on days with a TIBL in coastal cities.
基金the National Natural Science Foundation of China(No.21177087)the Shanghai Environmental Protection Bureau(SEPB)Program(No.09-26)
文摘Indoor air pollutants impact human health,comfort and productivity.The method of photocatalysis has been applied mainly in flow reactors and little information is available on indoor air pollutant removal in airtight reactors.In the paper,experiments were carried out to remove formaldehyde(HCHO),ammonia(NH_3) and volatile organic compounds(VOCs)in the airtight and ventilated chambers.Results demonstrated that 90.4%of HCHO,92.3%of NH_3 and 57.9%of VOCs were removed in the amine adsorption process,while 67.5% (hereinbefore,these are the mass fraction)of HCHO,60.0%of NH_3,and 61.2%of VOCs were removed in the photocatalytic process.However,ozone-assisted photocatalytic process showed great potential to degrade indoor air pollutants in the ventilated chamber.Factors and mechanisms of the photocatalytic degradation of HCHO, NH_3 and VOCs were also discussed.
