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1.
Since the majority of schools are housed in buildings dating from the 1960s and 1970s, a comprehensive construction and renovation program of school buildings has been carried out to improve the educational conditions in Korea. However, classrooms and computer rooms, with pressed wood desks, chairs and furnishings, as well as construction materials, might have negative effects on the indoor air quality. Furthermore, most schools have naturally ventilated classrooms. The purpose of this study was to characterize the concentrations of different indoor air pollutants within Korean schools and to compare their indoor levels within schools according to the age of school buildings. Indoor and outdoor air samples of carbon monoxide (CO), carbon dioxide (CO(2)), particulate matter (PM(10)), total microbial count (TBC), total volatile organic compounds (TVOCs) and formaldehyde (HCHO) were obtained during summer, autumn and winter from three sites; a classroom, a laboratory and a computer classroom at 55 different schools. The selection of the schools was based on the number of years since the schools had been constructed. The problems causing indoor air pollution at the schools were chemicals emitted by building materials or furnishings, and insufficient ventilation rates. The I/O ratio for HCHO was 6.32 during the autumn, and the indoor HCHO concentrations (mean = 0.16 ppm) in schools constructed within 1 year were significantly higher than the Korean Indoor Air Standard, indicating that schools have indoor sources of HCHO. Therefore, increasing the ventilation rate by means of a mechanical system and the use of low-emission furnishings can play key roles in improving the indoor air quality within schools.  相似文献   

2.
To devise and implement strategies to manage the quality of urban air, a metropolis needs air pollution data on which an air quality management plan can be formulated. Although air pollutants can come from several sources, many reports suggest that nitrogen dioxide from motor vehicle emissions is the major contributor to air pollution in cities. Since vehicles stop or move slowly through traffic intersections, concentrations of nitrogen dioxide (NO(2)) are expected to be relatively high at these sites. Inexpensive Ogawa passive samplers were placed at selected traffic intersections in the Durban Metropolis to trap the NO(2) which was then analysed by a sensitive laboratory-based method. The data obtained by this method was compared with data from sophisticated system comprising an active sampler cum on-line chemiluminescence detector. The sampling was done over a twelve month period to cover all seasons. Statistical analysis of the data showed that there was no significant difference between the means for the two methods. This study has established that an Ogawa passive sampler may be used as an economical and reliable collector for NO(2) in ambient air under varying climatic conditions. Further, the analysis method using a UV-Visible spectrophotometer was sensitive enough to detect NO(2) at the 10-20 ppb level. The cost of the method should be well within the budgets of most municipalities and it would motivate them to develop policies to alleviate traffic congestion.  相似文献   

3.
Environmental management involves controlling various forms of pollution to levels that do not pose a threat to the health of the people and the environment in general. This paper presents a framework to analyze sources of local air pollution in cities. Using an OLS model, an investigation is performed of the relationship among the concentrations of air pollutants [more precisely, concentrations of sulfur dioxide (SO2), dust, nitric oxide (NO), nitrogen dioxide (NO2), carbon oxide (CO) and ozone (O3)], economic activities, and meteorology. Time series analysis leads to a model, that explains a high degree of the variance in the air pollution data. The model is applied to daily time series from three measurement stations in innsbruck, Austria. Estimation results of the model generally fit with the expected relations. Space heating influences SO2, dust, and NO, while NO2 levels are primarily affected by traffic. These results also indicate interdependent relations among the pollutants NO, NO2, O3, and CO; O3 levels depend on temperature and sunshine.  相似文献   

4.
于秋冬两季,利用法国生产的自动监测仪对重庆市城区7条交通主干道的近地面空气质量进行了监测。结果表明:在监测期间,各个监测点PM1o是首要污染物,并且秋季比冬季污染严重,7条道路的日平均浓度为0.419mg/m^3,最大浓度为0.687mg/m^3,最大超标率为3.58倍;而NO2和SO2在冬季比秋季污染严重,NO2最高浓度是0.126mg/m^3,平均浓度是0.089mg/m^3,S02最高浓度是0.333mg/m^3,平均浓度是0.216mg/m^3,表明交通干道空气污染严重。  相似文献   

5.
Nitrous oxide is a greenhouse gas, and NO and NO2 play a key role in atmospheric chemistry. Nitrous oxide, NO, and NO2 fluxes from fertilized soils were measured six times per day by an automated flux monitoring system for one year, beginning on 21 May 1998. Pac choi (Brassica spp.) was cultivated for two months, and the plots were left fallow the remainder of the year. Two types of manure, poultry manure (PM) and swine manure (SM), and a chemical fertilizer, urea, were applied to the soil. The total amount of nitrogen applied in each case was 15 g N m(-2). The total fluxes from PM, SM, and urea for the year were 184, 61.3, and 44.8 mg N m(-2) for N2O, respectively; 9.95, 16.6, and 148 mg N m(-2) for NO, respectively; and -6.21, -7.23, and -7.84 mg N m(-2) for NO2, respectively. A negative correlation was found between the NO flux and the NO concentration of the chamber air just after the chamber was closed, when a flux from the atmosphere to soil was observed for 10 months. The mean gross NO production, the NO uptake rate constant, and the apparent compensation point for this period were 0.79 to 0.95 microg N m(-2) h(-1), 120 to 128 L m(-2) h(-1), and 5.65 to 7.35 ppbv, respectively.  相似文献   

6.
Methyl tertiary butyl ether (MTBE) was measured in air samples collected at hourly intervals near Blodgett Forest Research Station on the western slope of the Sierra Nevada, California, in July 1997, October 1998, and June through September 1999. Mixing ratios ranged from below the detection limit (< approximately 0.01 ppbv) to 0.5 ppbv, but were generally less than 0.3 ppbv. At these mixing ratios partitioning of MTBE into surface waters would lead to MTBE concentrations of less than 0.2 microg L(-1). As expected, MTBE mixing ratios were highly correlated with other anthropogenically emitted hydrocarbons. Based on the observed diurnal cycle of MTBE and its ratio to 2-methyl-butane (isopentane), we estimated the average regional daytime oxidant concentration to be (9 to 13) x 10(6) OH radicals per cubic centimeter, consistent with our earlier estimates for this region. Furthermore, MTBE ratios to toluene, another ubiquitous anthropogenic hydrocarbon, were generally consistent with regional transport and dilution, as well as atmospheric oxidation. Exceptions, pertaining to MTBE mixing ratios below or close to the detection limit, were associated with the influence of marine air masses that did not experience anthropogenic hydrocarbon input from California. With all these constraints in place, evidence for an additional atmospheric loss process, such as nonreversible deposition of MTBE, could not be established, and we conclude that any deposition is slow compared with removal from the atmosphere by the OH radical.  相似文献   

7.
An Electrical Low Pressure Impactor (ELPI) was used during spring and autumn 2003 in the centre of Strasbourg for the measurement of atmospheric aerosols size distribution. The concentration of NO(x) and SO(2) in air was simultaneously measured with specific analysers. Samples were collected in the range 0.007-10 microm in equivalent aerodynamic diameter size. Number distributions are representative of a pollution originating from urban traffic with a particle size distribution exhibiting a nucleation mode below 29 nm and an accumulation mode around 80 nm in size. A mean particle density equal to 39000+/-35000 total particles per cm(3) with a size ranging from 7 to 10 microm was obtained after a sampling period of 2 weeks in spring. About 86.9% of the number of particles have an aerodynamic diameter below 0.1 microm and 13.1% between 0.1 and 1 microm. Correlation coefficients between the number of particles impacted on each ELPI plate and gas concentrations (SO(2) and NO(x)) showed that the numbers of particles with diameter between 0.10 and 0.62 microm are highly related to the NO(x) concentration. This result indicates that particles are traffic induced since NO(x) is mainly emitted by cars as shown by measurements on various sites. Particles are less clearly correlated to the SO(2) concentration. Particle analysis on different ELPI plates for a sampling period of 2 weeks in autumn showed high level of soluble NO(3)(-), SO(4)(2-) and NH(4)(+) ions. Indeed, up to 90% b.w. of these three species were found in the particle range 0.1-1 microm. The formation of particulate NH(4)NO(3) is favoured by high NO(x) concentration, which induces the formation of gaseous HNO(3).  相似文献   

8.
The aim of the present study is to assess whether certain ecophysiological responses (contents of total phenols, total proanthocyanidins, and total and simple flavonols), in the needles of Aleppo pines (Pinus halepensis Mill.) may be valid bioindicators for the assessment of the air quality. Samples were taken at five natural sites polluted by various pollutants (NO, NO2, other NOx, SO2, and O3). The results show a decrease in total phenol concentrations with levels of nitrogen oxide pollutions (significant negative correlations between the total phenol concentrations and concentrations of NO, NO2, and other NOx). Total flavonoids (total flavonols and proanthocyanidins) are useful bioindicators for ozone pollution (significant negative correlations between total proanthocyanidins and the concentrations of ozone and significant positive correlations between total flavonols and the ozone pollution). Sulfur dioxide pollution is distinguished by low concentrations in quercetin, isorhamnetin, and kaempferol (significant negative correlations between these simple flavonols and the concentrations of SO2). This work confirms the strong interest of using the phenolic compounds of Pinus halepensis as biological indicators of air quality.  相似文献   

9.
Open road tolling (ORT) design has been considered as an effective means of smoothing highway traffic and reducing travel delay on toll highways. In this paper it is demonstrated that ORT can also achieve significant air quality benefits over the conventional toll plaza design. The near roadside carbon monoxide (CO) concentration levels can be reduced by up to 37%, and diesel particulate matter (DPM) emissions can decrease by as much as 58%. These large expected air quality benefits have great implications to the regional efforts of reducing mobile source air pollution toward achieving attainment status and healthier living environment.  相似文献   

10.
四川省城市环境空气质量及变化趋势   总被引:1,自引:0,他引:1  
邹军  杨柳 《四川环境》2010,29(4):50-53
本文根据2000~2009年四川省24个地级城市例行空气监测数据,按照《环境空气质量标准》(GB3095-1996)中的二级标准,采用综合污染指数法分析了四川省近10年环境空气质量的现状、变化趋势及影响因素。结果表明:从年际变化看,可吸入颗粒物浓度呈下降趋势,二氧化硫、二氧化氮浓度变化较平稳;年内变化显示,各污染物浓度季节变化明显,冬季污染最严重,污染程度由高到低的顺序为冬季、春季、秋季、夏季。全省综合污染指数呈下降趋势,空气污染程度得到了明显缓解,空气质量逐渐变好。  相似文献   

11.
Urbanization and development are associated with air pollution, including emissions of volatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene, and xylene (BTEX). For this study, we measured and investigated the outdoor concentrations of BTEX in Tehran, Iran. National Institute for Occupational Safety and Health (NIOSH, 1996) methods were applied to measure the concentrations of BTEX in winter and spring of 2015 at 46 air monitoring stations. BETX concentrations were also measured at 19 monitoring stations in June and July of 2003. In 2003, BTEX compound pollutants were observed at greater concentration in the eastern, central, and southern zones of Tehran than in other zones. The average concentrations of the BTEX compounds were 238 parts per billion (ppb), 130 ppb, 69 ppb, and 118 ppb, respectively, for benzene, toluene, ethylbenzene, and xylene. The benzene to toluene (B/T) ratios ranged from 0.8 to 3.2, which indicated that the gasoline used in the city was of poor quality at that time. In 2015, the BTEX concentrations in District 19 (south of Tehran) were higher than in the eastern and central regions, which included restricted “traffic zones” and the extensive development of public transportation systems. In the restricted traffic zones, only public vehicles, such as buses, taxis, ambulances, etc., and other authorized vehicles are allowed to operate. By ameliorating the quality of gasoline, encouraging the use of late model private cars, and development of subway and public transportation during the years between 2003 and 2015, the BTEX concentrations have fallen to levels that comply with Iran's air quality standards. The 2015 measurements revealed that the average concentrations of the BTEX compounds were 5.3, 9.2, 1.5, and 2.6 ppb, respectively. The B/T ratio fluctuated from 0.39 to 0.76, demonstrating the remarkable role that vehicle traffic plays in BTEX pollution.  相似文献   

12.
In autumn of 2008, the chemical characteristics of major secondary ionic aerosols at a suburban site in central Taiwan were measured during an annually occurring season of high pollution. The semicontinuous measurement system measured major soluble inorganic species, including NH(4)(+), NO(3)(-), and SO(4)(2-), in PM(10) with a 15 min resolution time. The atmospheric conditions, except for the influences of typhoons, were dominated by the local sea-land breeze with clear diurnal variations of meteorological parameters and air pollutant concentrations. To evaluate secondary aerosol formation at different ozone levels, daily ozone maximum concentration (O(3,daily max)) was used as an index of photochemical activity for dividing between the heavily polluted period (O(3,daily max) ≧80 ppb) and the lightly polluted period (O(3,daily max)<80 ppb). The concentrations of PM(10), NO(3)(-), SO(4)(2-), NH(4)(+) and total major ions during the heavily polluted period were 1.6, 1.9, 2.4, 2.7 and 2.3 times the concentrations during the lightly polluted period, respectively. Results showed that the daily maximum concentrations of PM(10) occurred around midnight and the daily maximum ozone concentration occurred during daytime. The average concentration of SO(2) was higher during daytime, which could be explained by the transportation of coastal industry emissions to the sampling site. In contrast, the high concentration of NO(2) at night was due to the land breeze flow that transport inland urban air masses toward this site. The simulations of breeze circulations and transitions were reflected in transports and distributions of these pollutants. During heavily polluted periods, NO(3)(-) and NH(4)(+) showed a clear diurnal variations with lower concentrations after midday, possibly due to the thermal volatilization of NH(4)NO(3) during daytime and transport of inland urban plume at night. The diurnal variation of PM(10) showed the similar pattern to that of NO(3)(-) and NH(4)(+) aerosols. This indicated that the formatted secondary aerosols in the inland urban area could be transported to the coastal area by the weak land breeze and deteriorated the air quality in the coastal area at night.  相似文献   

13.
基于模糊数学的大气环境质量综合评价   总被引:1,自引:0,他引:1  
魏毅 《四川环境》2012,31(3):61-64
鉴于大气环境质量评价中客观存在的不确定性和模糊性,运用模糊数学方法,选用SO2、NO2、PM10作为评价因子,参照大气环境质量标准,通过计算污染因子权重分配系数和隶属度对乌鲁木齐市2004年至2010年大气环境质量给出客观的评价,综合评价结果表明乌鲁木齐市总体大气环境质量为轻度污染(三级),但空气质量在逐年好转,SO2和PM10依然是乌鲁木齐市空气质量的制约因子,且NO2的权重在逐年上升。模糊综合评判考虑环境空气质量评价的模糊性,根据污染物浓度对各级别的贴近度考察污染物的级别,评价结果比较直观,可以细致准确的评价环境质量等级,评价结果基本可以反映环境空气污染的情况。  相似文献   

14.
Air pollution has become one of the main environmental concerns in China since the 1980s due to China's rapid economic growth and resultant pollution. However, it is difficult to directly evaluate the anthropogenic contribution to air pollution in China. The 2008 Olympic Games in Beijing provided a unique opportunity for testing the contribution of anthropogenic pollution because of the clean-up controls on air quality in Beijing enforced over the period of the Games. In this case study, we monitored the concentrations of major air pollutants before, during, and after the Olympics at a suburban site in Beijing. Atmospheric concentrations of PM10, PM2.5, NH3, NO2, SO2, and the particulate ions NH4+, NO3-, SO4(2-) Ca2+, Mg2+, and K+ all decreased during the Olympic period because of strict emission controls, compared with the same period from 2005 to 2007. For example, the average PM10 concentration (61 microg m(-3)) during the Olympics was only 37% of that (166 microg m(-3)) in the same month (August) from 2005 to 2007. However, just 1 mo and 1 yr after the Games had ended, mean concentrations of these pollutants had increased significantly again. This rapid "recovery' of air pollutant concentrations after the Olympics suggests that China needs to implement long-lasting decreases in its air pollution in Beijing and other major cities.  相似文献   

15.
In many regions of China, very rapid economic growth has been accompanied by air pollution caused by vehicle emissions. In one of these regions, the Pearl River Delta, the variations of ground-level ozone and its precursors were investigated. Overall, the ambient concentrations of NO(2) increased quickly between 1995 and 1996, but then slightly decreased due to stringent nitrogen oxide (NO(x)) emission controls. Nonetheless, ambient NO(2) levels in the Pearl River Delta remained high. The regional average concentrations of volatile organic compounds (VOCs) were 290 ppbC in summer and 190 ppbC in autumn. Local emissions and long-distance transportation of pollutants play important roles in the regional distribution of VOCs. Ambient O(3) production is significant in urban areas and also downwind of cities. The relative incremental reactivities (RIRs), determined by an observation-based model, showed that ground-level ozone formation in the Guangzhou urban area is generally limited by the concentrations of VOCs, but there are also measurable impacts of NO(x).  相似文献   

16.
This research explores the attitudes of children from different socioeconomic backgrounds toward consumption with the aim of establishing a framework for incorporating the subject of (responsible) consumption into the upper elementary school curriculum. This study draws upon the four-step methodological procedure, including consumption diaries, focus-group sessions, interviews, and concept mapping, conducted among 140 upper elementary school children in the Netherlands between September 2010 and January 2011. The consumption diaries, chronological documents recording purchase, use and waste of materials, were used both as analytical tools and the means to stimulate environmental awareness. Comparison of the clusters generated by concept mapping analysis shows that there are significant differences between attitudes of children from different socioeconomic backgrounds. While pupils from the “well-to-do” predominantly ethnically Dutch schools showed greater awareness of and concern about their own consumptive patterns, children from less economically advantaged and ethnically mixed schools demonstrated lower environmental awareness and concern. However, children from the disadvantaged schools demonstrated more pro-environmental consumptive behaviors associated with the money-saving activities.  相似文献   

17.
选取2013—2016年粤港澳大湾区11市大气主要污染物数据,采用社会网络分析法(SNA)对粤港澳大湾区大气污染的空间关联性进行实证研究。结果发现:①大湾区城际大气主要污染物的空间关联均呈现出较典型的网络结构特征。②城际大气污染存在明显的空间关联和空间溢出,各城市空间联系越来越密切。③大湾区大气污染空间网络具有稳定性特征,PM2.5和SO2的空间溢出得到有效控制,而PM10和NO2的空间溢出具有长期稳定性。④珠海、佛山、惠州、中山在大湾区城际大气污染空间关联网络中处于中心地位。⑤各城市在大气污染空间网络中存在明显的非均衡地位。  相似文献   

18.
农村中小学环境教育的几点思考   总被引:2,自引:0,他引:2  
中小学环境教育是基础教育的组成部分,首要任务是培养青少年爱护环境、保护环境的意识。在农村进行中小学环境教育,方式和方法要适合农村特点。为此,对农村中小学环境教育进行初步探讨,提出方法和措施。  相似文献   

19.
National reports along with numerous statewide studies indicate that the physical infrastructure of American schools is crumbling. At the same time there is emerging evidence that school building quality matters for children's academic achievement. We integrate two separate literatures that have demonstrated that low school building quality as well as high rates of student mobility each contribute to reduced academic achievement by showing that these two variables statistically interact. Elementary school children in 511 New York City public schools have lower achievement scores if they attend schools of poor structural quality and with high rates of student mobility. The significant main and interactive effects of school building quality and student mobility on standardized test scores occur independently of socioeconomic and racial composition of the school.  相似文献   

20.
利用衡水市环境监测站2005—2007年度大气例行检测的数据,对衡水市大气中主要污染物SO^2、NO^2、PM10体积质量值的逐日数据进行统计分析,得出了衡水市空气污染的现状和时间变化规律:(1)污染物体积质量值的月变化曲线呈槽型分布,非取暖期的空气状况明显好于取暖期,取暖期SO^2平均体积质量是非取暖期的2.45倍;(2)污染物体积质量值的日变化曲线基本为两高两低型,其中取暖期污染指数早晨出现极高值的时间比非取暖期明显偏晚;(3)污染物体积质量值的年变化表明了SO^2的体积质量在降低,而NO^2的体积质量却有了小幅增长。  相似文献   

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