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1.
An evaluation of air pollution at the Bily Kriz mountains in the Czech Republic is given. Annual daily concentrations of sulphur dioxide (SO2), nitrogen oxides (NOx), particulate matter of size 10 mm (PM10) and ozone (O3) measured in the years 1994–2000 are presented. Air pollution at Bily Kriz is assessed with the reference to the European Union Directives and the standards adopted by the Czech Republic. In general, the concentrations of air pollutants were lower in 1996 for ozone and decreased for SO2, NOx and PM10 from 1994. The daily values of SO2 and PM10 exceeded the European Union limits in approximately 0.0% and 5.5% of cases, respectively. The values of ozone exceeded the limits for the considered period.  相似文献   

2.
A long-term study of measurement of concentration of NOx, SO2 and TSP pollutants have been done in a port and harbour region in India. Monthly measurements of gaseous and particulate pollutants were made at six monitoring stations from January 1997 to December 2000. Meteorological data was also simultaneously collected. In this study, the relationship between monitored ambient air quality data and meteorological factors, such as wind speed, temperature, is statistically analysed, using the SPSS package. The monthly mean concentrations of NOx, SO2 and TSP were in the range of 19.5–59.0 μg/m3, 8.6–51.3 μg/m3 and 88.2–199.3 μg/m3, respectively. The results show that TSP is strongly correlated with NOx and SO2 with a correlation coefficient of 0.83 and 0.82, respectively. The correlation coefficients for TSP, NOx, and SO2 with wind are –0.78, –0.78, and –0.88, respectively.  相似文献   

3.
This paper presents a statistical model that is able to predict carbon monoxide (CO) concentrations as a function of meteorological conditions and various air quality parameters. The experimental work was conducted in an urban atmosphere, where the emissions from cars are prevalent. A mobile air pollution monitoring laboratory was used to collect data, which were divided into two groups: a development group and a testing group. Only the development dataset was used for developing the model. The model was determined by using a stepwise multiple regression modelling procedure. Thirteen independent variables were selected as inputs: non-methane hydrocarbon (NMHC), methane (CH4), suspended dust, carbon dioxide (CO2), nitrogen oxide (NO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), wind speed, wind direction, temperature, relative humidity and solar energy. It was found that NO has the most effect on the predicted CO concentration. The contribution of NO to the CO concentration variations was 91.3%. Adding in the terms for NO2), NMHC and CH4 improved the model by only a further 2.3%. The derived model was shown to be statistically significant, and model predictions and experimental observations were shown to be consistent.  相似文献   

4.
The ambient air concentrations and fluxes of various anionic species were sampled by MOUDI, TSP and dry deposition plates at a traffic sampling site in Taichung, central Taiwan. In the sampling period, from September to December 2000, the ambient air particle concentrations (PM1, PM2.5, PM10 and TSP) were lower in the September than in the other three months (October to December). The reason is that the northwest wind brought more particles (diameter less than 10 μm) and the higher wind speed caused higher dry deposition fluxes and TSP concentrations in the last three months. The anion species percentages of TSP were 0.24%, 13.7%, 0.52%, 12.0%, 18.9'% and 54.6% for F-, Cl-, Br-, NO2-, NO3- and SO42-, respectively. The results revealed that SO42-, NO3-, Cl- and NO2- were the dominant species at the traffic sampling site. The ion-size distributions of Cl-, NO2- and NO3- were unimodal, the main peak being between 3.2 and 5.6 μm. In contrast, the size distribution of SO42- was bimodal, with the main peaks in the particle size ranges 0.32.0.56 μm and 3.2.5.6 μm. The ambient average particle dry deposition flux was 6.28 μg/m2/s, and the dry deposition fluxes were 0.01, 94.6, 0.05, 34.7, 72.2 and 376.4 ng/m2/s for F-, Cl-, Br-, NO2-, NO3- and SO42-, respectively. The dry deposition velocities were 3.10, 0.03, 3.67, 0.05, 1.54, 2.03 and 3.67 cm/s for F-, Cl-, Br-, NO2-, NO3- and SO42-, respectively.  相似文献   

5.
Concentrations of ambient suspended particulates were measured at Tzu Yun Yen temple (120°, 34′ 10”E; 24°, 16′, 12”N), using a Universal sampler and dry deposition plates. The temple is a characteristic incense-burning and semi-open sampling site. PM2.5 concentrations for Period 1 (average 901μg/m3) were higher than those for Period 2 (average 701μg/m3). Results for average PM2.5-10concentrations showed equal distributions in Period 1 and Period 2. Average ratios of PM2.5/ PM10 were higher in Period 1 (74%) than Period 2 (71%). In addition, the suspended particulate (PM10) elements concentrations during Zhong Yuan Jie, and the first and 15th days of nong li for each month (Chinese lunar calendar) were all higher than during non-Zhong Yuan Jie and non-first and non-15th days. Furthermore, the dry deposition velocities of manganese in fine particulates (PM2.5) and suspended particulates (PM10) were 1.43 and 0.751cm/s, respectively, and the dry deposition velocities of cadmium in fine particulates (PM2.5) and suspended particulates (PM10) were 1.86 and 0.991cm/s, respectively.  相似文献   

6.
The air quality in the industrial area and surroundings of the city of Paulinia (state of Sao Paulo, Brazil) has been investigated by analysing the concentration of air pollutants (SO2, PM10, NO, NO2, CO and ozone) and identifying the main sources of air pollution. A mobile pollutant monitoring unit was used to collect the data at five different sites from November 2000 to July 2002. Critical pollutants were determined based on air quality standards, and sources were identified by principal component analysis. Photochemical reactions play an important role in Paulinia's air pollution: three out of five monitored sites showed levels exceeding the standard air quality of ozone. SO2 and PM10 appeared as pollutants deserving special attention. All the monitored sites showed vehicles and industrial plants (which release SO2) to be significant sources of pollution. Depending on the location, ozone was related mainly with vehicular or industrial sources.  相似文献   

7.
The CMB8 model was applied for source apportionment of particulate matter in Bangkok area. The 24 h of ambient data were collected and analysed for elemental composition during December 1996 to January 1997 by high volume air samplers at a station in Bangkok, Thailand. Seven source profiles and the average mass concentrations of 42 ambient data were used to run the chemical mass balance (CMB8) model. The source apportionment by CMB8 gave similar results comparing with factor analysis – multiple regression (FA–MR) model of the same data. The results revealed that major sources of particulate matter in Bangkok were: soil (33%), road dust (33%) and automobile (15%). The minor source contributions were: sea salt (4.34%), refuse incineration and biomass burning (0.84%), steel mill (0.62%) and fuel oil combustion (0.35%). The lack of source profile for biomass or open burning in Bangkok resulted in much lower predicted contribution of this source when compared to that from FA–MR. When apply this CMB8 model with daily ambient data, the result revealed that one fourth of daily CMB8 source apportionment had high value of 2 (>4). These exceedance values of Chi2 also point out that one of the selected sources (biomass burning) may not be the true contributing sources. Presumably, accurate biomass burning source profile is needed to improve the CMB calculation of source contributions for particulate matter in Bangkok metropolitan area.  相似文献   

8.
In order to comply in 2010 with the emission ceilings proposed by European commission under the convention on transboundary air pollution, Greece has to develop and implement a cohesive strategy affecting all the sectors of the economy. The RAINS model was used for the evaluation of the environmental and economic impacts arising from the use of a number of control technologies under alternative energy scenarios. To this purpose a number of modifications regarding the input databases of RAINS were made. The analysis clearly reveals that the reduction of SO2 emissions can be achieved in a lower cost compared to the reduction of NOx emissions. Moreover, the complementarity of CO2 abatement policies and the SO2/NOx abatement policies is also accented.  相似文献   

9.
Atmospheric acid aerosols were sampled by two annular denuder systems (ADS) and a micro-orifice uniform deposit impactor (MOUDI) at a traffic site in central Taiwan. Theoretical analysis showed that the relative artifact for HNO3 gas sampling was about 0.53 when the initial HNO3 concentration was under 0.2 µg/m³ and should be considered carefully. The concentrations of gaseous acid at the traffic sampling site were higher than those in the other study. The size distributions of acid aerosols were unimodal for Cl-, NO2-, and NO3-, and bimodal for SO42-. The dominant acid ions in particles less than 18 µm were SO42-, NO3-, NO2- and Cl-.  相似文献   

10.
Roadside particulate levels (PM10) at 30 locations throughout the Kathmandu Valley, Nepal are reported. There were seven sampling cycles from January to December 1999. PM10 levels ranged between 1000 and 6000 μ/m3 for 1-h sampling. There was no consistent trend in PM10 levels with respect to monitoring cycle, average precipitation or wind speed. There is no WHO guideline for PM10 (no safe exposure threshold), but the EPA 24-h standard is 150 μ/m3. The major sources of roadside PM10 include dust re-suspension from vehicular movement and human activity, and particulate emissions from old vehicles. Other sources of PM10 in the valley include cement and brick factories. Studies are currently being conducted to determine the lead content of PM10 from roadside samples. Additional studies are warranted to assess the potential adverse human health effects of acute or chronic exposure to high particulate levels reported in this study.  相似文献   

11.
Studies of air quality predictors based on neural networks   总被引:1,自引:0,他引:1  
In recent years, urban air pollution has emerged as an acute problem because of its negative effect on health and living conditions. Regional air quality problems, in general, are linked to violations of specified air quality standards. The current study aims to find neural network based air quality predictors, which can work with a limited number of datasets and are robust enough to handle data with noise and errors. A number of available variations of neural network models, such as the Recurrent Network Model (RNM), the Change Point Detection Model with RNM (CPDM), the Sequential Network Construction Model (SNCM), the Self Organising Feature Model (SOFM), and the Moving Window Model (MWM), were implemented using MATLAB software for predicting air quality. Developed models were run to simulate and forecast based on the annual average data for 15 years from 1985 to 1999 for seven parameters, viz. VOC, NOx, CO, SO2, PM10, PM2.5 and NH3 for one county of California, USA. The models were fitted with first nine years of data to predict data for remaining six years. The models, in general, could predict air quality patterns with modest accuracy. However, the SOFM model performed extremely well in comparison with the other models for predicting long-term (annual) data.  相似文献   

12.
During the last decade, there has been worldwide concern with global climate change, which has been induced by greenhouse gases (GHGs) due to the use of fossil fuels. The CO2 emissions from fossil fuel combustion have been identified as the single most significant source of GHG emissions into the atmosphere. Realising the need to control and regulate emissions of pollutants, the objective of the present study estimates the trend of CO2, SO2 and NOx between the periods 1991-92 and 1996-97. An input-output structural decomposition analysis approach is used to determine their sources of change. It also provides a set of alternative scenarios for the year 2001-2 and 2006-7. The sources of changes in the amount of CO2, SO2 and NOx emissions are categorised into four factors: the ecoefficiency, the structure of production, the structure of demand, and the volume of demand. Results indicate that the electricity sector contributes more towards direct, as well as indirect, emission coefficients. The petroleum product sector also contributes more in this respect. The dominant role is played by the structure of demand and the volume of demand.  相似文献   

13.
This paper assesses CO2 mitigation strategies in Delhi and Mumbai against the dynamics of local pollutants. After testing against techno-economic feasibility, compressed natural gas (CNG) technology, four-stroke two-wheelers and battery-operated vehicles (BOV) were selected as candidate options for Mumbai and Delhi. Multiple constrained optimisation for finding out the optimal mix of vehicles to meet the travel demand under the business-as-usual scenario for the period of CO2 mitigation targets of 5, 10, 15, 20, 25% resulted in reduced stock of diesel and petrol vehicles, with the reduction spanning over different points of the above time period. In the case of Mumbai, battery-operated three-wheelers dominated the vehicular mix, with the share of CNG vehicles remaining at a standard level. CO2 reduction targets did not influence the CNG option significantly. CO2 mitigation influenced the dynamics of local pollutants considerably in both Delhi and Mumbai. In Delhi, TSP and SOx reduction levels against the CO2 mitigation target were found to be significant. In Mumbai, the percentage reduction in local pollution (TSP in particular) was higher than the target CO2 reduction. Local pollutants other than TSP and SOx showed an increasing trend against the CO2 mitigation strategies in Delhi. In the case of Mumbai, all non-target pollutants showed a falling trend against the CO2 mitigation strategies, though insignificantly for pollutants other than TSP and SOx.  相似文献   

14.
A series of transition metal oxide catalysts (Zn, Ti, Cu, Ni, Fe and V) supported on Al2O3 and SiO2 were prepared using the incipient wetness impregnation method. Their performances on NO reduction and CO oxidation followed the sequence of TiO2 > CuO/ZnO > CuO > ZnO. TiO2 supported on SiO2 was more active than that on Al2O3, while ZnO had the opposite performances. The activities of CuO/Al2O3 and ZnO/SiO2 were both decreased with the calcination temperature increasing because the sintering and agglomerations of catalysts were occurred at high temperature.  相似文献   

15.
A statistical analysis of ozone (O3) concentrations and meteorological parameters was performed to determine the relationship between meteorological changes and ambient O3 concentrations in the Southeast United States. The correlation between average daily maximum O3 concentration and various meteorological variables was analysed on a monthly basis from April through October during 1980-1994. The correlations were strongest during the summer months, particularly June, July, and August. Analysis of long term O3 concentration trends indicates increasing trends during the 1980s and decreasing trends during the early 1990s.  相似文献   

16.
The treatment of Zn(II)-bearing wastewater by immobilised Sulfate Reducing Bacteria (SRB) sludge beads of inner cohesive nutrient source was investigated, by which the traditional problems in SRB methods were resolved. The mechanism and kinetics model on Zn(II) removal were studied. The results showed that SO42− was reduced to S2− on the surface of SRB sludge beads, and Zn(II) precipitated outside beads. The effect of internal diffusion could be neglected, and the chemical reaction was the rate determining step. The reaction kinetics was followed by Micaelis-Menten formula, and the constants, Ks and vmax were 8.99 mg⋅L−1 and 0.018 mg⋅L−1⋅s−1, respectively.  相似文献   

17.
The changes in dissolved organic carbon (DOC), N-NO3, N-NH4 and P-PO4 concentrations in response to fluctuations in the groundwater table were investigated in the peatlands of Biebrza National Park and some of its surrounding sites. The lowering of the groundwater table during summer time was accompanied by an increase in P-PO4 and N-NH4 concentrations, and in some cases they were exceptionally high compared with undisturbed water. Concentrations of both nutrients correlated with groundwater levels. Decreasing the groundwater level promoted higher concentrations of both nutrients. Nevertheless, elevated concentrations of P-PO4 and N-NH4 occurred in groundwater during the summer months when the outflow of water from peatland was slow. The N-NO3 and DOC concentrations did not change markedly with the lowering of groundwater table or during different seasons.  相似文献   

18.
This paper focuses the application of a measurement technique for determining atmospheric C2–C6 hydrocarbons after canister sampling and analysis by gas chromatography/flame ionisation detection (GC/FID), as well of an adsorption-sampling technique for C6–C11 compounds and GC/FID analysis after thermal desorption and cryogenic concentration. Tens of samples collected at Giesta, a rural area located 20 km to the SE of the coastal Portuguese city of Aveiro, were analysed. The characterisation of C2 C11 hydrocarbons is presented, considering seasonal variations, diurnal cycles, the influence of air masses and different photochemical conditions. Ratios between hydrocarbons and principal components analysis were applied to differentiate between biogenic and anthropogenic sources.  相似文献   

19.
In recent years, the rapid increase in population density has caused increases in the consumption of fuel, and the outdoor air quality has deteriorated in the crowded urban areas of Turkey. Erzurum, a city in the eastern part of Turkey, is influenced by air pollutants such as SO2 and suspended particles. It is known that, in general, the air pollution concentrations have a close relationship with meteorological factors. In this study, the relationship between outdoor air quality data and meteorological factors, such as wind speed, rainfall, temperature, sunshine hours and relative humidity, is statistically analysed, using the code SPSS. According to the results obtained through multiple linear regression analysis, there are moderate levels of correlation between SO2 and particle concentrations and meteorological factors in Erzurum.  相似文献   

20.
The present paper describes the application of the CALMET meteorological model and CALPUFF plume dispersion model to the Yatagan district to study the impact of Yatagan Power Plant emissions on the SO2 levels on December 2000 in the region. Results indicate that SO2 concentrations over the city depend strongly on advected emissions from the power plant and on the local variation of the wind field and limited vertical mixing conditions. It is found that South Westerly and light winds and the night time surface inversion layers lead to accumulation of pollutants coming from the power plant over the Yatagan district. The results are compared with the observations obtained from Local Environmental Authorities of Mugla. The simulation results indicate that the maximum ground level concentrations were found northeast from the source, which agrees with the measurements, but differ in terms of magnitudes.  相似文献   

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