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881.
Heavy Metal Pollution of Surface Soil in the Thrace Region, Turkey   总被引:1,自引:0,他引:1  
Abstact Samples of surface soil were collected at 73 sites in the Thrace region, northwest part of Turkey. Two complementary analytical techniques, epithermal neutron activation analysis (ENAA) and atomic absorption spectrometry (AAS) with flame and graphite furnace atomization were used to determine 35 elements in the soil samples. Concentrations of As, Cd, Co, Cu, Mn, Ni, Pb and Zn were determined using AAS and GF AAS, and ENAA was used for the remaining 27 elements. Results for As, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu Eu, Fe, Hf, I, In, K, La, Mn, Mo, Na, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, Ti, U, V and Zn are reported for the first time for soils from this region. The results show that concentrations of most elements were little affected by the industrial and other anthropogenic activities performed in region. Except for distinctly higher levels of Pb, Cu, Cd and Zn in Istanbul district than the median values for the Thrace region, the observed distributions seem to be mainly associated with lithogenic variations. Spatial distributions of As, Cd, Cr, Cu, Ni, Pb and Zn were plotted in relation to the concentration values in soil using Geographic Information System (GIS) technology  相似文献   
882.
孙翠玲  辛红林  冯雪阳 《环境工程》2006,24(6):76-76,87
通过实验探讨了火焰原子吸收法测定痕量重金属的最佳条件和消除干扰液的使用,为准确测定其含量,提供了很好的经验。  相似文献   
883.
Washoff of road deposited sediment into storm drainsystems is one of the major contributors to nonpoint sourcepollution in urban fluvial networks. These sediments contain avariety of potentially toxic organic and inorganic contaminants.Road sediment from 13 locations in an urban (non-industrialized)drainage basin, and soil from 10 background (control) locationswere collected to assess total and labile fractions of Al, Co,Cu, Fe, Mn, Ni, Pb and Zn. Four digestions, of varying strength,were used to assess contaminant levels, these included: a totalfour-acid digestion, a microwave-assisted digestion withconcentrated nitric acid (USEPA Method 3051), a 0.5 M `cold' HCl,and a 0.05 M EDTA (pH 7). Road sediment data indicate that Al,Co, Fe, Mn and Ni were primarily lithogenic in origin, while Cu,Pb and Zn showed very significant anthropogenic signals, mostprobably from vehicle-related sources. Median Pb concentrationenrichment ratios for the EDTA extraction were about 42,indicating an extreme anthropogenic signal. The weak extractants(HCl and EDTA) are considered in this study to be superior intheir ability to characterize the degree of anthropogeniccontamination and should be utilized more widely in environmentalcontaminant studies.  相似文献   
884.
石家庄市大气颗粒物元素组分特征分析   总被引:2,自引:1,他引:1  
为研究石家庄市大气颗粒物的污染特征及其来源,于2013年4—5月在主城6区分别采集TSP、PM10和PM2.5颗粒物样品,利用ICP-MS分析其中的22种元素浓度。结果表明,石家庄市城区Ca、Fe元素在各粒径颗粒物中含量都较高,PM2.5中的S、K含量较高,PM10和TSP中Mg、Al的浓度相对较高。颗粒物的主要来源为燃煤尘、道路尘和建筑尘,TSP、PM10和PM2.5具有较好的统计相关性和同源性。  相似文献   
885.
采用4种微波消解体系对聚四氟乙烯(PTFE)材质滤膜采集的PM2.5样品进行消解,利用电感耦合等离子体质谱(ICP-MS)测定样品中Cr、Mn、Cu、As、Cd 5种重金属元素含量,并计算其空白加标和样品加标回收率,建立了测定PTFE材质滤膜采集的PM2.5样品中重金属元素的最优微波消解体系。结果表明,4种消解体系下,空白加标回收率和样品加标回收率均处于合理范围,分别为95.3%~116.3%和93.3%~118.5%。其中,HNO3放置过夜+H2O2消解体系具有空白值低、测定稳定性强、操作简便、绿色环保、对人体健康危害小等优点,能够满足大批量PM2.5样品中重金属总量的快速、高效、准确分析的要求。  相似文献   
886.
In order to evaluate the impact of atmospheric pollutants emitted by the industrial settlement of Milazzo (Italy) on agriculture, sulphur dioxide and ozone levels in air were monitored and the data were used to estimate yield losses of the most widespread cultures. Trace element concentrations in crops and soils were also detected and metabolic profiles of soil microbial communities were considered. Vibrio fischeri test was used to appraise airborne pollutant ecotoxicity and epidemiological studies on causes of death distribution were carried out to characterize health state of people living in the area. All the sampling points were selected in farms on the basis of a theoretical meteo-diffusive model of industrial air pollutants. Experimental SO2 and O3 values mainly exceeded the threshold established by Italian and EU regulations to protect vegetation and they correspond to estimated significant crop losses. Conversely toxic element residues in soils and in agroalimentary products were generally lower than the fixed values. SO2 and O3 concentrations, toxic element contents and ecotoxicity levels of airborne pollutants were not related only to industrial site emissions, while the fluctuations on metabolic profiles of soil microbial communities seem to agree with the predicted deposition of xenobiotic compounds from the industrial plants. The epidemiological study evidenced a better health state of populations living in the investigated area than in the Messina province and the Sicily region but, inside the area, males living in the municipalities closest to the industrial settlement exhibited a worst health state than those in the very far ones.  相似文献   
887.
大气预浓缩仪-GC/FPD测定环境空气中的痕量硫化物   总被引:1,自引:0,他引:1  
采用大气预浓缩仪-GC/FPD建立了环境空气中7种含硫化合物的测定方法。结果表明,经惰性化改造后的大气预浓缩仪-GC/FPD测定系统的基线低,对硫化物无残留。7种化合物的线性回归方程的相关系数均在0.995以上,高、中、低3种浓度的空白加标回收率分别为98.6%~105.3%、99.1%~103.7%、85.7%~99.7%,除硫化氢的相对标准偏差为10.9%外,其余6种含硫化合物的相对标准偏差可控制在6.9%以内。当进样体积为400 m L时,方法的检出限在0.10~1.1 ng/m3。CO2、H2O对实际样品的测定无干扰。因此,该方法能够满足目前监测工作的要求,更加适用于环境空气中痕量含硫化合物的测定。  相似文献   
888.
采用高分辨电感耦合等离子体质谱法测定地下水中14种稀土元素,并选择Rh作内标,可消除测定中的质谱干扰和非质谱干扰,使方法在0μg/L~100μg/L范围内线性良好。方法检出限为0.002μg/L~0.005μg/L,实际水样的加标回收率为80.0%~117%,RSD为2.1%~3.8%。  相似文献   
889.
A field study was conducted around two thermal power plants of India to quantify the changes in foliar elemental concentrations due to emission in a low rainfall tropical area. Sulphur dioxide and particulates were at high levels which may cause serious ecological effects. Emission from the power plants has altered the elemental concentrations in the leaves of evergreen and deciduous plants. The foliar total-S and SO4 2–-S levels were significantly higher in all the plants growing at polluted sites. However, the organic-S content was more or less unaltered. In evergreen plants, the SO4 2–-S content increased gradually from summer through winter, whereas in the deciduous plants there was a higher magnitude of increase after onset of new leaves during summer. With the increasing pollution load, foliar Ca2+ and K+ contents increased, whereas N content decreased. The reduction in N content was greater during summer in evergreen plants and during winter in deciduous plants. The plants growing closer to the power plants accumulated more trace elements (Mn, Fe, Cd, Pb and Ni) as compared to those growing at distant sites. In deciduous plants the leaf fall during winter lowered down the trace element  相似文献   
890.
采用微波消解-电感耦合等离子体质谱法测定水系沉积物中12种元素,通过优化试验相关条件消除质谱干扰和非质谱干扰对测定的影响,使方法在0μg/L~200μg/L范围内线性良好,当取样质量为0.25 g,定容体积为50 m L时,各元素的方法检出限为0.002 mg/kg~0.05 mg/kg。用该方法测定沉积物标准物质,6次测定结果均在标准值范围内,RSD为1.3%~6.1%,实际样品的加标回收率为83.0%~97.0%。  相似文献   
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