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Heavy Metal Distribution Map in Soil by Using GIS Techniques 被引量:1
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作者 M. Altan O. Ayyildiz S. Malkoc +1 位作者 B. Yazici S. Koparal 《Journal of Environmental Science and Engineering》 2011年第1期15-20,共6页
A detailed investigation was conducted to understand the contamination characteristics and distributions of heavy metal pollution in terms of contributions of the heavy metal concentrations as mg/kg ofCd, Cr, Cu, Ni, ... A detailed investigation was conducted to understand the contamination characteristics and distributions of heavy metal pollution in terms of contributions of the heavy metal concentrations as mg/kg ofCd, Cr, Cu, Ni, Zn, Pb, Fe and Mn in the urban soil in Eskisehir city center. The amount of these heavy metals were determined from 15 soil sample points collected within urban area and every sample point included 6 separated samples for chemical analyses. The results indicated that concentration values of all metals except Ni and Cr in soils were below the risky limit pollution values which are recommended by Turkey Ministry of Environment and Forestry in some sample points. Spatial distribution maps were created and recoded, in terms of these heavy metals concentrations as contribution to heavy metal pollution in soil, through Geographical Information Systems techniques. As a result, risky areas were modeled in terms of contamination of heavy metal and it is shown that, every different risky area can be interpreted based on buildings in city center quickly and easily. 展开更多
关键词 Heavy metal pollution in soil GIS generation recoded map pollution distribution.
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Prediction Flashover Voltage on Polluted Porcelain Insulator Using ANN
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作者 Ali Salem Rahisham Abd-Rahman +2 位作者 Waheed Ghanem Samir Al-Gailani Salem Al-Ameri 《Computers, Materials & Continua》 SCIE EI 2021年第9期3755-3771,共17页
This paper aims to assess the effect of dry band location of contaminated porcelain insulators under various flashover voltages due to humidity.Four locations of dry bands are proposed to be tested under different sev... This paper aims to assess the effect of dry band location of contaminated porcelain insulators under various flashover voltages due to humidity.Four locations of dry bands are proposed to be tested under different severity of contamination artificially produce using salt deposit density(SDD)sprayed on an insulator.Laboratory tests of polluted insulators under proposed scenarios have been conducted.The flashover voltage of clean insulators has been identified as a reference value to analyze the effect of contamination distribution and its severity.The dry band dimension has been taken into consideration in experimental tests.The flashover voltage has been predicted using an artificial neural network(ANN)technique based on the laboratory test data.The ANN approach is constructed with five input data(geometry the insulator and parameters of contamination)and flashover voltage as the output of the model.Results indicated that the pollution distribution based on the proposed scenario has a significant influence on the flashover voltage performances.Validation of the ANN model reveals that the relative error values between the experimental results and the prediction appeared to be within 5%.This indicates the significant efficiency of the ANN technique in predicting the flashover voltage insulator under test. 展开更多
关键词 INSULATOR pollution distribution artificial neural network dry band
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Pollutant concentrations and pollution loads in stormwater runoff from different land uses in Chongqing 被引量:35
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作者 Shumin Wang Qiang He +2 位作者 Hainan Ai Zhentao Wang Qianqian Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第3期502-510,共9页
To investigate the distribution of pollutant concentrations and pollution loads in stormwater runoff in Chongqing,six typical land use types were selected and studied from August 2009 to September 2011.Statistical ana... To investigate the distribution of pollutant concentrations and pollution loads in stormwater runoff in Chongqing,six typical land use types were selected and studied from August 2009 to September 2011.Statistical analysis on the distribution of pollutant concentrations in all water samples shows that pollutant concentrations fluctuate greatly in rainfall-runoff,and the concentrations of the same pollutant also vary greatly in different rainfall events.In addition,it indicates that the event mean concentrations (EMCs) of total suspended solids (TSS) and chemical oxygen demand (COD) from urban traffic roads (UTR) are significantly higher than those from residential roads (RR),commercial areas (CA),concrete roofs (CR),tile roofs (TRoof),and campus catchment areas (CCA);and the EMCs of total phosphorus (TP) and NH3-N from UTR and CA are 2.35-5 and 3 times of the class-III standard values specified in the Environmental Quality Standards for Surface Water (GB 3838-2002).The EMCs of Fe,Pb and Cd are also much higher than the class-III standard values.The analysis of pollution load producing coefficients (PLPC) reveals that the main pollution source of TSS,COD and TP is UTR.The analysis of correlations between rainfall factors and EMCs/PLPC indicates that rainfall duration is correlated with EMCs/PLPC of TSS for TRoof and TP for UTR,while rainfall intensity is correlated with EMCs/PLPC of TP for both CR and CCA.The results of this study provide a reference for better management of non-point source pollution in urban regions. 展开更多
关键词 urban land uses stormwater runoff pollution load pollutant concentration distribution
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Influence of haze pollution on water-soluble chemical species in PM2.5 and size-resolved particles at an urban site during fall 被引量:7
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作者 Geun-Hye Yu Yan Zhang +1 位作者 Sung-Yong Cho Seungshik Park 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第7期370-382,共13页
To investigate the influence of haze on the chemical composition and formation processes of ambient aerosol particles,PM_(2.5) and size-segregated aerosol particles were collected daily during fall at an urban site ... To investigate the influence of haze on the chemical composition and formation processes of ambient aerosol particles,PM_(2.5) and size-segregated aerosol particles were collected daily during fall at an urban site of Gwangju,Korea.During the study period,the total concentration of secondary ionic species(SIS) contributed an average of 43.9% to the PM_(2.5) ,whereas the contribution of SIS to the PM_(2.5) during the haze period was 62.3%.The NO_3 and SO^(2-)_4 concentrations in PM_(2.5) during the haze period were highly elevated,being 13.4 and 5.0 times higher than those during non-haze period,respectively.The PM,NO^-_3,SO^(2-)_4,oxalate,water-soluble organic carbon(WSOC),and humic-like substances(HULIS) had tri-modal size distributions peaks at 0.32,1.0,and 5.2 μm during the non-haze and haze periods.However,during the non-haze period they exhibited dominant size distributions at the condensation mode peaking at 0.32 μm,while on October 21 when the heaviest haze event occurred,they had predominant droplet mode size distributions peaking at 1.00 μm.Moreover,strong correlations of WSOC and HULIS with SO^(2-)_4,oxalate,and K+at particle sizes of 〈 1.8 μm indicate that secondary processes and emissions from biomass burning could be responsible for WSOC and HULIS formations.It was found that the factors affecting haze formation could be the local stable synoptic conditions,including the weak surface winds and high surface pressures,the long-range transportation of haze from eastern China and upwind regions of the Korean peninsula,as well as the locally emitted and produced aerosol particles. 展开更多
关键词 Haze pollution Size distribution Secondary ionic species Humic-like substances Stable synoptic conditions
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Aerosol size distributions during haze episodes in winter in Jinan, China 被引量:8
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作者 Yuwei Sun Xuehua Zhou Wenxing Wang 《Particuology》 SCIE EI CAS CSCD 2016年第5期77-85,共9页
Number concentrations and distributions of 10-10,000 nm particles in a large city (Jinan) in the North China Plain were measured in winter 2009. The mean number concentrations of nucleation mode (10-20 nm), Aitken... Number concentrations and distributions of 10-10,000 nm particles in a large city (Jinan) in the North China Plain were measured in winter 2009. The mean number concentrations of nucleation mode (10-20 nm), Aitken mode (20-100 nm), and accumulation mode (100-1000 nm) particles, as well as total particles were 925, 6898, 2476, and 10,299cm-3, respectively. Two severe haze episodes, with elevated concentrations caused by pollutants accumulating, were observed. Accumulation mode particle concen- trations were significantly higher during the episodes than on clear days, and nucleation mode particle concentrations were pronouncedly higher on clear days than during the episodes. The peaks of domi- nant number, surface area, and mass size distributions were around 30-50, 200-300, and 200-400 rim, respectively, both during the haze episodes and on clear days, but elevated mass and surface area con- centrations around 500-600 nm were also observed during the haze episodes, suggesting these particles had significant contributions to haze formation. These particles were probably formed through larger droplets in cloud and fog evaporating. Two new particle formation events, probably triggered by strong photochemical processes on clear days and significant traffic emissions during haze episode 2, were found. Significant insights were made into haze formation in a oolluted Chinese urban area. 展开更多
关键词 Aerosol size distributions Hazy and clear days Polluted city China
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Development of EMC-based empirical model for estimating spatial distribution of pollutant loads and its application in rural areas of Korea 被引量:1
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作者 Qitao Yi Hui Li +1 位作者 Jin-Woo Lee Youngchul Kim 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第9期1-11,共11页
An integrated approach to easily calculate pollutant loads from agricultural watersheds is suggested and verified in this research. The basic concepts of this empirical tool were based on the assumption that variation... An integrated approach to easily calculate pollutant loads from agricultural watersheds is suggested and verified in this research. The basic concepts of this empirical tool were based on the assumption that variations in event mean concentrations(EMCs) of pollutants from a given agricultural watershed during rainstorms were only attributable to the rainfall pattern.Fifty one sets of EMC values were obtained from nine different watersheds located in the rural areas of Korea, and these data were used to develop predictive tools for the EMCs in rainfall runoff. The results of statistical tests of these formulas show that they are fairly good in predicting actual EMC values of some parameters, and useful in terms of calculating pollutant loads for any rainfall event time span such as daily, weekly, monthly, and yearly. This model was further checked in for its field applicability in a reservoir receiving stormwater after a cleanup of the sediments, covering 17 consecutive rainfall events from 1 July to 15 August in2007. Overall the predicted values matched the observed values, indicating the feasibility of this empirical tool as a simple and useful solution in evaluating timely distribution of nonpoint source pollution loads from small rural watersheds of Korea. 展开更多
关键词 EMC Empirical model Nonpoint source pollution Spatial distribution
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