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Climate change,ambient air pollution,and students'mental health
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作者 Jing-Xuan Wang Xin-Qiao Liu 《World Journal of Psychiatry》 SCIE 2024年第2期204-209,共6页
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
关键词 Climate change ambient air pollution Mental health Energy structure Public policy Sustainable development
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Low ambient temperature and air pollution are associated with hospitalization incidence of coronary artery disease:Insights from a cross-sectional study in Northeast China
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作者 Rui Jiang Lingling Xu +4 位作者 Yue Liu Guangna Zhao Chun Xing Youyuan Li Yongchen Wang 《Frigid Zone Medicine》 2023年第4期232-241,I0007-I0013,共17页
Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for asso... Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for associations between meteorological changes and hospitalization incidences related to CAD and its subtypes,especially in cold regions.This study aimed to systematically investigate the relationship between exposure to meteorological changes,air pollutants,and hospitalization for CAD in cold regions.Methods:We conducted a cross-sectional study using hospitalization records of 86,483 CAD patients between January 1,2009,and December 31,2019.Poisson regression analysis,based on generalized additive models,was applied to estimating the influence of hospitalization for CAD.Results:Significant associations were found between low ambient temperature[-10℃,RR=1.65;95%CI:(1.28-2.13)]and the incidence of hospitalization for CAD within a lag of 0-14 days.Furthermore,O_(3)[95.50μg/m^(3),RR=12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.Furthermore,O_(3)[95.50μg/m^(3),RR=1.12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.The effect curve of CAD hospitalization incidence significantly increased at lag days 2 and 4 when NO_(2)and O_(3)concentrations were higher,with a pronounced effect at 7 days,dissipating by lag 14 days.No significant associations were observed between exposure to PM,SO_(2),air pressure,humidity,or wind speed and hospitalization incidences due to CAD and its subtypes.Conclusion:Our findings suggest a positive correlation between short-term exposure to low ambient temperatures or air pollutants(O_(3)and NO_(2))and hospitalizations for CAD,STEMI,and NSTEMI.These results could aid the development of effective preparedness strategies for frequent extreme weather events and support clinical and public health practices aimed at reducing the disease burden associated with current and future abnormal weather events. 展开更多
关键词 meteorological changes ambient temperature air pollution coronary heart disease Poisson regression analysis
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Exploring the relationship between ambient sulfur dioxide and semen quality parameters:A systematic review and meta-analysis
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作者 Seyed Sobhan Bahreiny Mojtaba Aghaei +3 位作者 Mohammad Reza Dabbagh Hamid Ghorbani Moslem Javidan Reza Mohammadpour Fard 《Asian pacific Journal of Reproduction》 CAS 2024年第1期12-21,共10页
Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality parameters.Methods:A systematic literature search was conducted to identify relevant studies investigating the as... Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality parameters.Methods:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality parameters.This search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and Scopus.Pooled effect estimates with 95%confidence intervals(CI)were calculated using percent changes(PC).The meta-analysis included seven studies with 6711 participants and 15087 semen samples.Results:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality parameters.In particular,SO2 exposure was associated with a significant decrease in progressive motility(PC=0.032;95%CI:-0.063 to-0.001;P=0.044)and sperm concentration(PC=-0.020;95%CI:-0.036 to-0.005;P=0.012).However,no statistically significant associations were observed for total sperm count(PC=-0.038;95%CI:-0.079 to 0.003;P=0.070),seminal fluid volume(PC=-0.009;95%CI:-0.048 to-0.030;P=0.662)and sperm motility(PC=-0.17;95%CI:-0.363 to 0.022;P=0.830).In addition,the results of the subgroup analysis revealed specific variables that were associated with the decrease in relevant sperm parameters.Conclusions:This systematic review and meta-analysis provides compelling evidence supporting a consistent negative association between exposure to ambient SO2 and semen quality parameters. 展开更多
关键词 Semen quality Sulfur dioxide ambient air pollution META-ANALYSIS
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Association between Ambient Air Pollution and Hospital Emergency Admissions for Respiratory and Cardiovascular Diseases in Beijing: a Time Series Study 被引量:19
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作者 ZHANG Ying WANG Shi Gong +6 位作者 MA Yu Xia SHANG Ke Zheng CHENG Yi Fan LI Xu NING Gui Cai ZHAO Wen Jing LI Nai Rong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第5期352-363,共12页
Objective To investigate the association between ambient air pollution and hospital emergency admissions in Beijing. Methods In this study, a semi-parametric generalized additive model (GAM) was used to evaluate the... Objective To investigate the association between ambient air pollution and hospital emergency admissions in Beijing. Methods In this study, a semi-parametric generalized additive model (GAM) was used to evaluate the specific influences of air pollutants (PM10, SO2, and NO2) on hospital emergency admissions with different lag structures from 2009 to 2011, the sex and age specific influences of air pollution and the modifying effect of seasons on air pollution to analyze the possible interaction. Results It was found that a 10μg/m3 increase in concentration of PMlo at lag 03 day, SO2 and NO2 at lag 0 day were associated with an increase of 0.88%, 0.76%, and 1.82% respectively in overall emergency admissions. A 10 lag/m3 increase in concentration of PM10, SO2 and NO2 at lag 5 day were associated with an increase of 1.39%, 1.56%, and 1.18% respectively in cardiovascular disease emergency admissions. For lag 02, a 10 μg/m3 increase in concentration of PM10, SO2 and NO2 were associated with 1.72%, 1.34%, and 2.57% increases respectively in respiratory disease emergency admissions. Conclusion This study further confirmed that short-term exposure to ambient air pollution was associated with increased risk of hospital emergency admissions in Beijing. 展开更多
关键词 ambient air pollution Time-series Hospital emergency admissions
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Simply air:Vanadium-catalyzed oxidative kinetic resolution of methyl o-chloromandelate by ambient air 被引量:1
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作者 Lu Yin Xian Jia +1 位作者 Xing Shu Li Albert S.C. Chan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期774-777,共4页
Vanadium-catalyzed oxidative kinetic resolution(OKR) of methyl o-chloromandelate 2a,key intermediate of the well-known oral antiplatelet agent(S)-clopidogrel,was achieved by ambient air for the first time.The air ... Vanadium-catalyzed oxidative kinetic resolution(OKR) of methyl o-chloromandelate 2a,key intermediate of the well-known oral antiplatelet agent(S)-clopidogrel,was achieved by ambient air for the first time.The air oxidation system,which was composed of vanadium and tridentate Schiff base ligands derived from amino alcohols and salicylaldehyde derivatives,afforded an efficient and economic approach to the target intermediate with high enantioselectivities(99%ee). 展开更多
关键词 ambient air Vanadium-catalyzed OKR Methyl o-chloromandelate Schiff base ligands
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Ambient Air Quality Surveillance and Indexing in and around Mining Clusters in Western Kachchh Region, Gujarat, India 被引量:1
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作者 B. Anjan Kumar Prusty 《Open Journal of Air Pollution》 2012年第2期22-30,共9页
Generation of baseline information about ambient air quality of any given region assumes significance, when the area is 1) an active mine site, 2) proposed to be mined out in future, and 3) industrialization in the ar... Generation of baseline information about ambient air quality of any given region assumes significance, when the area is 1) an active mine site, 2) proposed to be mined out in future, and 3) industrialization in the area is in fast pace. Ambient air quality monitoring (with respect to SPM, RPM, SO2, NOx and CO) was carried out in and around two mining complexes in western parts of Kachchh district in Gujarat to generate baseline air quality status of the area. This area has two major mine complexes and various large scale industrial projects (thermal power plants, cement plants and several ports and jetties) are also in pipeline. Ambient air sampling was carried out in eight locations within five km radial distance from two major mine sites, i.e. Panandhro and Mata-na-Madh, with four locations for each mine site. Air Quality Indexing was done for all the locations, since it is a simplest way for the prediction of ambient air quality status of any region with respect to industrial, residential and rural areas. Of the eight locations studied the air quality for six locations fell under fairly clean (Light Air Pollution, AQI 25-50) category, while the rest (rural areas in the region), had relatively better air quality and fell under clean (Clean Air, AQI 10-25) category. 展开更多
关键词 air QUALITY Index ambient air QUALITY MINING WESTERN KACHCHH
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Variation in Parameters of Ambient Air Quality in National Capital Territory (NCT) of Delhi (India) 被引量:1
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作者 Anunay A. Gour Santosh K. Singh +1 位作者 Sushil K. Tyagi Anubha Mandal 《Atmospheric and Climate Sciences》 2015年第1期13-22,共10页
Air Pollution is an escalating problem worldwide fuelled by increasing anthropogenic activities, speedy development, rapid industrialization, transportation, superfluous use of fossil fuel consumption, increasing glob... Air Pollution is an escalating problem worldwide fuelled by increasing anthropogenic activities, speedy development, rapid industrialization, transportation, superfluous use of fossil fuel consumption, increasing global power needs, etc. Also the diverse meteorological factors influence our environment to a great extent. Population explosion has led to remarkable increase in vehicular population. The use solely depends upon the lifestyle of the citizen. Any change in the lifestyle has a remarkable effect on the air we breathe. A comprehensive database for pollution levels from the year 2006 to 2010 was analyzed for a main traffic intersection and a non-traffic area in Delhi (India). The paper asserts that pollutant concentration levels on weekend are lower than those on weekdays (increase on Sundays with respect to weekdays is CO 2.98 times, PM2.5 1.18 times, NO 1.62 times, NO2 5.76 times, SO2 1.27 times and O3 1.15 times). The pollution levels have been found to attenuate on public holidays and weekends. Pollution can hence be related to the weekly cycle of human activities. Pollutions due to vehicular emissions on roads, rails, air or water all serve as major sources of pollution. Hence, viably possible solutions for pollution control can also be achieved by controlling the magnitude of traffic flow on roads. 展开更多
关键词 ambient air Quality Emission SEASONAL VARIATION WEEKEND Effect DELHI
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Influence of the ambient air temperature on the electrical contact reliability of electromagnetic relay 被引量:2
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作者 YAO Fang ZHENG Jian-rong HUANG Zhang-wu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期485-489,共5页
The dynamic contact resistances of HH52P electromagnetic relays are measured under different ambient air tem- perature. Their diagnostic parameters are extracted and determined. It is found that the ambient air temper... The dynamic contact resistances of HH52P electromagnetic relays are measured under different ambient air tem- perature. Their diagnostic parameters are extracted and determined. It is found that the ambient air temperature obviously influ- ences some parameters. In order to research its influence on the electrical contact reliability of electromagnetic relay, the statistic analysis is applied to study the static contact resistance, the max of the dynamic contact resistance and the bounce time. It is found that the ambient air temperature regularly influences the three parameters. Thoroughly, the phenomenon is studied and analyzed in the point of material science so as to probe into the essential matter of it. 展开更多
关键词 周围空气温度 电磁式继电器 电气插头 回跳时间
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Ambient air temperature effects on the temperature of sewage sludge composting process
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作者 HUANG Qi-fei CHEN Tong-bin +1 位作者 GAO Ding HUANG Ze-chun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期1004-1007,共4页
Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled... Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1 : 0 : 1 and 3 : 1 : 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process: composting temperature changed 2.4-6.5℃ when ambient air temperature changed 13℃. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process: composting temperature changed 0.75-1.3℃ when ambient air temperature changed 8-15℃. Hysteresis effect was observed in composting temperature's responses to ambient air temperature. When the ventilation capability of pile was excellent(at a volume ratio of 1:0:1), the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate(at a volume ratio of 3:1:2), the hysteresis time was IonQ and ranging 1.9-3.1 h. 展开更多
关键词 sewage sludge COMPOSTING ambient air temperature HYSTERESIS
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Analysis of the Ambient Air Quality of Tarlac City: Baseline Data for Environmental Management Plan 被引量:1
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作者 Xyris Gerard A. Fernandez Lolita V. Sicat Maria Elena D. David 《材料科学与工程(中英文A版)》 2011年第1X期64-70,共7页
关键词 环境管理计划 空气质量分析 基准数据 空气污染物 环境空气监测 城市中心 呼吸系统疾病 总悬浮微粒
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Measurement of air kerma rate and ambient dose equivalent rate using the G(E) function with hemispherical CdZnTe detector
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作者 Ping Huang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期71-77,共7页
Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation dete... Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation detectors such as cerium chloride doped with lanthanum bromide(LaBr_3(Ce)), thallium doped with cesium iodide(sI(Tl)), thallium doped with sodium iodide(NaI(Tl)),and high-purity germanium(HPGe) primarily use the spectroscopy-dose rate function(G(E)) to achieve the accurate measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)). However, the spectroscopy-dose rate function has been rarely measured for a CZT detector. In this study, we performed spectrum measurement using a hemispherical CZT detector in a radiation protection standards laboratory. The spectroscopy-dose rate function G(E) of the CZT detector was calculated using the least-squares method combined with the standard dose rate at the measurement position. The results showed that the hemispherical CZT detector could complete the measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)) by using the G(E) function at energies between 48 keV and 1.25 MeV, and the relative intrinsic errors were, respectively, controlled within ± 2. 3 and ± 2. 1%. 展开更多
关键词 CDZNTE Spectroscopy-dose RATE G(E) FUNCTION air kerma RATE ambient DOSE equivalent RATE Relative intrinsic error
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Overview on Air Pollution Control Promoting the Improvement of Ambient Air Quality in Tianjin
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作者 Dong Yanping Wang Xin +1 位作者 Liu Wei Zhu Qiujun 《Meteorological and Environmental Research》 CAS 2017年第4期69-72,共4页
To improve ambient air quality and return citizens blue sky and white clouds,national and local administrative departments all issue corresponding countermeasures to strictly prevent and control air pollution,reduce t... To improve ambient air quality and return citizens blue sky and white clouds,national and local administrative departments all issue corresponding countermeasures to strictly prevent and control air pollution,reduce total pollutant emission,and improve environmental management level. In this paper,taking Tianjin as an example,change situation of regional air pollution and its prevention and control management situation were summarized. 展开更多
关键词 ambient air quality air POLLUTION COUNTERMEASURES Environmental management
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Ambient Air Pollution and Pulmonary Tuberculosis in Malaysia
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作者 Mohd Hatta Abdul Mutalip Tee Guat Hiong +5 位作者 Stefanie Ebelt Sarnat Mohd Hazrin Hashim Noor Aliza Lodz Sayan Pan Mohd Shahrul Mohd Nadzir Asmah Razali 《Health》 2018年第12期1634-1649,共16页
Introduction: The possible impact of ambient air pollution exposure on the development of active tuberculosis (TB) remains obscure. This study investigated the potential role of ambient air pollution in activating pul... Introduction: The possible impact of ambient air pollution exposure on the development of active tuberculosis (TB) remains obscure. This study investigated the potential role of ambient air pollution in activating pulmonary TB (PTB) compared to extrapulmonary TB (EPTB). Materials and Methods: Data on TB cases were obtained from national surveillance data in Malaysia during 2013 and air pollution data were obtained from 52 air-monitoring stations around the country for the 3-year period of 2011-2013. Analyses were performed to estimate the odds of PTB vs. EPTB with changes in the 3-year (2011-2013) average Air Pollutant Index (API) and specific ambient air pollutants. Results: Results showed that the 95th-percentile of API levels during 2011-2013 was moderate and it was not associated with PTB. However, the odds of active PTB compared to EPTB was significantly elevated with the 95th-percentile levels for particulate matter with an aerodynamic diameter of 10 μm or less (aOR = 1.006, 95% CI: 1.002, 1.011), p-value Conclusions: These results provide suggestive evidence of the effects of ambient air pollution on development of active pulmonary TB compared to extrapulmonary TB. Additional research on the impacts of ambient air pollution on TB is warranted. 展开更多
关键词 ambient air POLLUTION air POLLUTANT Index PULMONARY TB MALAYSIA
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Effects of Using Wind Guiding Nets to Improve Prevailing Ambient Wind on Direct Air-cooled Condensers 被引量:1
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作者 YANG Jianguo LIU Da ZHANG Zhaoying JU Xiaoli 《中国电机工程学报》 EI CSCD 北大核心 2012年第2期I0001-I0020,共20页
关键词 直接空冷凝汽器 环境风场 风网 入口流量 冷凝器风扇 质量流率 倒灌风 空气
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Assessment of Gaseous and Particulate Pollutants in the Ambient Air in Al Mirfa City, United Arab Emirates
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作者 Entisar Al Katheeri Fadi Al Jallad Muthanna Al Omar 《Journal of Environmental Protection》 2012年第7期640-647,共8页
From 2007-2009, National Energy and Water Research Center (NEWRC) on behalf of Abu Dhabi Water and Electricity Authority (ADWEA) conducted a long term baseline study of nitrogen dioxide (NO2), carbon monoxide (CO), su... From 2007-2009, National Energy and Water Research Center (NEWRC) on behalf of Abu Dhabi Water and Electricity Authority (ADWEA) conducted a long term baseline study of nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), ozone (O3) and particulate matter 2, SO2, and 8 hour average of CO were within the acceptable levels of 400, 300 and 30,000 μg/m3 respectively, whereas the levels of O3 as 8 hour average (3) and PM10 (3) occasionally exceeded the FEA permissible limits during the study period. Seasonal variation based on three years data reveals that the highest concentration of NO2 and SO2 were during winter and for CO and O3 during summer months. Results indicate that the levels of SO2 and CO were significantly controlled and improved while the fuel combustion of Al Mirfa power plant had increased from 2007 to 2009. Dust has significantly impact on the air quality by elevated levels of PM10 exceed in several instances associated with regional sand- storm during the monitoring period. 展开更多
关键词 ambient air Quality Monitoring SEASONAL VARIATIONS SANDSTORM
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The Health Cost of Ambient Air Pollution in Lagos
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作者 Lelia Croitoru Jiyoun Christina Chang Joseph Akpokodje 《Journal of Environmental Protection》 2020年第9期753-765,共13页
Globally, air pollution is a significant cause of death, illness and social discomfort. The problem is particularly severe in Nigeria, the country with the highest number of premature deaths due to ambient particulate... Globally, air pollution is a significant cause of death, illness and social discomfort. The problem is particularly severe in Nigeria, the country with the highest number of premature deaths due to ambient particulate matter pollution in Sub Saharan region. It is especially worrying in Lagos, the country’s commercial capital and one of the world’s fastest growing megacities. Despite growing concerns about its deadly impacts, there is currently no reliable monetary estimate of the effects of ambient air pollution, nor a comprehensive control plan in Lagos. Using available ground-level monitored data and the most recent valuation techniques, this paper estimates that in 2018 alone, ambient fine particulate matter (PM2.5) caused about 11,200 premature deaths, and generated a health cost of US$2.1 billion in Lagos. This is equivalent to about 2.1 percent of Lagos’ GDP in the same year. These results call for an urgent plan of action to improve air quality in the city, with primary focus on the main pollution sources: road transport, industrial emissions, and power generation. 展开更多
关键词 ambient air Pollution VALUATION Health Cost
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Trace Metals in Fine and Respirable Ambient Air Particulates on Trinidad’s West Coast
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作者 Himawatee Baboolal Derrick Balladin Samantha Chadee 《Journal of Geoscience and Environment Protection》 2020年第6期61-81,共21页
The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline... The paper analyzed the concentrations of trace metals in fine and respirable particulates (fine-PM<sub>1</sub> and PM<sub>2.5</sub>;respirable-PM<sub>10</sub>) to determine baseline concentrations in the ambient air and the factors impacting its distribution such as land use and time of year when levels may be concerning to public health. Measurements of particulates along with meteorological parameters were made at four sites over the heavily populated west coast of Trinidad (10<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">&#176</span></span>32'N, 61<span style="font-size:10.0pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">&#176</span></span>18'W) during March ’15-May ’16, representing rural, urban, mixed background and industrial land uses. The study found mean levels of trace metals to be highest at the industrial and urban stations. Public health exceedances (referenced to the Canadian AAQ public health standards <a href="#ref23">(Ontario-MoE, 2012)</a>) were measured for beryllium, cadmium, chromium, iron, manganese and nickel (in PM<sub>10</sub>). Iron, manganese and nickel, most associated with particulates at the industrial station, were in frequent exceedance. Beryllium—concentrated in coarse PM (PM<sub>2.5-10</sub>) with only a single measured exceedance at the mixed background station likely poses minimal threat to the health of the nearby population. Cadmium—concentrated in fine PM which peaked once only at the rural station was likely due to an irregular event within a narrow timeframe during the time of sampling. Iron and manganese were frequently above the Canadian public health threshold, but predominated in the coarse PM fraction, suggesting localised sources. Nickel, concentrated in the fine PM fraction, was frequently in exceedance particularly at the industrial station. Cadmium and nickel are genotoxic and should be regulated in order to reduce the burden of toxic carcinogens to which the population can be exposed. 展开更多
关键词 ambient air Pollution Fine and Respirable Particulates Trace Metals
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An Analysis of Ambient Air Quality Conditions Over Delhi, India From 2004 to 2009
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作者 Jhumoor Biswas Era Upadhyay +1 位作者 Mugdha Nayak Anil Kumar Yadav 《Atmospheric and Climate Sciences》 2011年第4期214-224,共11页
We analyzed 1-hour, 8-hour and 24-hour averaged criteria pollutants (NO2, SO2, CO, PM22.5, and PM10) during 2004 - 2009 at three observational sites i.e. Income Tax Office (ITO), Sirifort and Delhi College of Engineer... We analyzed 1-hour, 8-hour and 24-hour averaged criteria pollutants (NO2, SO2, CO, PM22.5, and PM10) during 2004 - 2009 at three observational sites i.e. Income Tax Office (ITO), Sirifort and Delhi College of Engineering (DCE) in Delhi, India. The analysis reveals increased pollutant concentrations at the urban ITO site as compared to the other two sites, suggesting the need to better locate hot spots in designing the monitoring network. There is also significant year to year variation in the design value trends of criteria pollutants at these three sites, which may be attributed to meteorological variations and local-level emission fluctuations. Correlations among criteria pollutants vary annually and spatially from site to site, indicating the heterogeneous nature of air mix. The annual ratios of CO/NOx are considerably higher than SO2/NOx confirming that vehicular source emissions are the primary contributors to air pollution in Delhi. The seasonal analysis of criteria pollutants reveals relatively higher concentrations in winter because of limited pollutant dispersion and lower concentrations during the monsoon period (rainy season). The diurnal averages of criteria pollutants reveal that vehicular emissions strongly influence temporal variations of these pollutants. Weekdays and weekend diurnal averages do not show noticeable differences. 展开更多
关键词 ambient air Quality Status CRITERIA POLLUTANTS Data ANALYSIS
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Studies on Interrelations among SO<sub>2</sub>, NO<sub>2</sub>and PM<sub>10</sub>Concentrations and Their Predictions in Ambient Air in Kolkata
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作者 Sayanti Kar Phalguni Mukherjee 《Open Journal of Air Pollution》 2012年第2期42-50,共9页
In this paper we have first of all studied the interrelations among the concentrations of SO2, NO2 and PM10 and then predicted their future level of concentrations in the ambient air of Kolkata. The data collected fro... In this paper we have first of all studied the interrelations among the concentrations of SO2, NO2 and PM10 and then predicted their future level of concentrations in the ambient air of Kolkata. The data collected from West Bengal Pollution Control Board website have been used to construct second degree, third degree and four degree polynomial equations using MATLAB software. Since a curve in a small interval can be approximated by a line segment in that small interval, we have observed that better result can be achieved if we replace the curves piece meal wise in small intervals by line segments during January-April, May-August and September-December months. The multiple regression equations among the aforesaid three parameters have been established to predict the value of each parameter in terms of the remaining two. A further improvement in terms of reducing the number of dependent variables has been made using the results of correlation coefficients. Finally, we have predicted the value of each parameter in terms of only one dependent variable. 展开更多
关键词 ambient air Multiple Correlation-Coefficients KOLKATA
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Observation of selective surface element substitution in FeTe_(0.5)Se_(0.5) superconductor thin film exposed to ambient air by synchrotron radiation spectroscopy
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作者 张念 刘晨 +7 位作者 赵佳丽 雷涛 王嘉鸥 钱海杰 吴蕊 颜雷 郭海中 奎热西 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期540-545,共6页
A systematic investigation of oxidation on a superconductive Fe Te_(0.5)Se_(0.5)thin film,which was grown on Nb-doped SrTiO_3(001) by pulsed laser deposition,has been carried out.The sample was exposed to ambien... A systematic investigation of oxidation on a superconductive Fe Te_(0.5)Se_(0.5)thin film,which was grown on Nb-doped SrTiO_3(001) by pulsed laser deposition,has been carried out.The sample was exposed to ambient air for one month for oxidation.Macroscopically,the exposed specimen lost its superconductivity due to oxidation.The specimen was subjected to in situ synchrotron radiation photoelectron spectroscopy(PES) and x-ray absorption spectroscopy(XAS) measurements following cycles of annealing and argon ion etching treatments to unravel what happened in the electronic structure and composition after exposure to air.By the spectroscopic measurements,we found that the as-grown FeTe_(0.5)Se_(0.5)superconductive thin film experienced an element selective substitution reaction.The oxidation preferentially proceeds through pumping out the Te and forming Fe–O bonds by O substitution of Te.In addition,our results certify that in situ vacuum annealing and low-energy argon ion etching methods combined with spectroscopy are suitable for depth element and valence analysis of layered structure superconductor materials. 展开更多
关键词 11 iron-based superconductor oxidation mechanism in ambient air selective surface element substitution synchrotron radiation spectroscopy
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