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1.
This study compared the variations in the mass of certain particles at an urban site, Washington, DC, and at a remote site, Shenandoah National Park, VA, in the eastern United States. Seven years (1991-1997) of Interagency Monitoring of Protected Visual Environments (IMPROVE) fine particulate matter (PM2.5), PM10, coarse fraction, SO4(2-), and total sulfur data were used for this study together with available meteorology/climatology data. Various statistical modeling and analysis procedures, including time series analysis, factor analysis, and regression modeling, were employed. Time series of the constituents were divided into four terms: the long-term mean, the intraannual perturbation, the interannual perturbation, and the synoptic perturbation. PM2.5 at the two sites made up approximately 72% of the total mass for PM10, and the coarse fraction made up the remaining 28%, on average. Thirty-one percent of the PM2.5 at the DC site and 42% at the Shenandoah site was SO4(2-), based on average data for the entire period. At the DC site, the two main contributors to the constituent mass were the long-term mean and the synoptic perturbation terms, and at the Shenandoah site, they were the long-term mean and the intra-annual perturbation terms. This suggested that the constituent mass at the two sites was affected by very different processes. The terms that provided the principal contribution to the constituent mass at the two sites were studied in detail. At the DC site, dew point trends, a climate variable, were the primary driver of the 7-year trends for PM2.5, PM10, the coarse fraction, and total sulfur, and SO2 emission trends were the primary driver of the trends for SO4(2-). SO2 emission trends influenced the trends for PM2.5 and total sulfur, appearing as the second term in the model, but only parameters dealing with climate trends had significant effects on the trends for PM10 and the coarse fraction. At the Shenandoah site, only parameters dealing with climate trends affected long-term particle trends.  相似文献   

2.
The present work describes the application of an analytical procedure, utilizing ultra performance liquid chromatography (UPLC) coupled with mass spectrometry instrumentation, for the determination of 253 multiclass pesticides, classified in six different groups. Solid phase extraction was applied for the isolation and pre-concentration of target compounds in water samples. Surface waters of the lakes located in Northern Greece (Volvi, Doirani, and Kerkini), were collected in two time periods (fall/winter 2010 and spring/summer 2011) and analyzed, applying the developed analytical methods. Spatial distribution of detected pesticides was visualized using interpolation methods and geographical information systems (GIS). Pesticides with maximum concentrations were amitrole, propoxur, simazine, chlorpyrifos, carbendazim, triazophos, disulfoton-sulfone, pyridaben, sebuthylazine, terbuthylazine, atrazine, atrazine-desethyl, bensulfuron-methyl, metobromuron, metribuzin, rotenone, pyriproxyfen, and rimsulfuron. In Lake Kerkini, mainly carbamates and triazines were determined at elevated concentrations, near the coastal point of the NW side of the lake. Seasonal variations were strong among the applied pesticide classes and determined concentrations, indicating the contribution of pesticide application patterns and rainfall. Lake Doirani exhibited organophosphate pesticides at higher concentrations mainly at coastal points, while triazines emerged as the main pollutant during spring sampling. Lake Volvi exhibited the highest pesticide concentrations, mostly triazines and ureas at the central part of the lake. The occurrence of extreme values and nonconstant seasonal variations indicated that the concentrations were increased disproportionately during the second sampling, as a result of the varying contribution of pollution sources right after the application period. In all cases, the total concentration of pesticides increased during the second sampling period.  相似文献   

3.
In order to elucidate the global distribution of dioxins and related compounds, such as PCDDs, PCDFs and coplanar PCBs, levels of these compounds were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters and open seas near Japan, Taiwan, Philippines, Indonesia, Seychelles and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Indian Ocean and the North Pacific Ocean. PCDDs, PCDFs and coplanar PCBs were detected in almost all the specimens collected from all the locations surveyed, indicating widespread contamination by these compounds in the marine environment. Higher concentrations of dioxins and coplanar PCBs were detected in the samples from temperate Asian regions, plausibly due to larger usage and anthropogenic generation in highly industrialized countries around the East China Sea and the South China Sea, such as Japan, Korea, Taiwan, Hong Kong and coastal China.  相似文献   

4.
2006-2007年采暖季、风沙季和非采暖季分别在抚顺市的6个采样点采集PM10样品,用等离子体原子发射光谱(ICP-AES)法测定样品中Ti、Al、Mn、Mg、Ca、Na、K、Cu、Zn、As、Pb、Cr、Ni、Co、Cd、Fe、V等17种元素的含量,并用地质累积指数对其污染状况进行初步评价。结果表明:(1)从PM10中元素在不同采样点的含量看,抚顺市PM10中Ti、Mn、Mg、Cu、Zn、Pb、Cr、Ni、Co这9种元素在各采样点间的差别较大;Al、Ca、Na、K、As、Cd、Fe、V这8种元素差别较小。(2)从PM10中元素在不同采样季的含量看,抚顺市PM10中Mn、Mg含量的季间差别较大,其余15种元素季间差别较小。(3)Zn、Cd污染较重;Ti、Al、Mg、Ca、Na、K、As、Fe和V污染较轻;其他6种元素在6个采样点和3个采样季污染程度差别较大。(4)水库采样点各元素污染级别均不是最高;新华采样点PM10中Cu、Zn、Pb、Cr、Ni、Co、Cd污染级别均较高。(5)3个采样季PM10中Cd、Zn污染均较重,属于重度或严重污染;在采暖季PM10中Cu、Pb、Cr的地质累积指数较风沙季、非采暖季大;在非采暖季PM10中Mn、Co受到的污染比采暖季和风沙季稍严重。  相似文献   

5.
Heavy metal pollution in China: Origin,pattern and control   总被引:21,自引:2,他引:21  
GOAL, SCOPE AND BACKGROUND: Heavy metal is among one of the pollutants, which cause severe threats to humans and the environment in China. The aim of the present review is to make information on the source of heavy metal pollution, distribution of heavy metals in the environment, and measures of pollution control accessible internationally, which are mostly published in Chinese. METHODS: Information from scientific journals, university journals and governmental releases are compiled focusing mainly on Cd, Cu, Pb and Zn. Partly Al, As, Cr, Fe, Hg, Mn and Ni a included also in part as well. RESULTS AND DISCUSSION: In soil, the average contents of Cd, Cu, Pb and Zn are 0.097, 22.6, 26.0 and 74.2 mg/kg, respectively. In the water of the Yangtze River Basin, the concentrations of Cd, Cu, Pb and Zn are 0.080, 7.91, 15.7 and 18.7 microg/L, respectively. In reference to human activities, the heavy metal pollution comes from three sources: industrial emission, wastewater and solid waste. The environment such as soil, water and air were polluted by heavy metals in some cases. The contents of Cd, Cu, Pb and Zn even reach 3.16, 99.3, 84.1 and 147 mg/kg, respectively, in the soils of a wastewater irrigation zone. These contaminants pollute drinking water and food, and threaten human health. Some diseases resulting from pollution of geological and environmental origin, were observed with long-term and non-reversible effects. CONCLUSIONS: In China, the geological background level of heavy metal is low, but with the activity of humans, soil, water, air, and plants are polluted by heavy metals in some cases and even affect human health through the food chain. RECOMMENDATIONS AND OUTLOOK: To remediate and improve environmental quality is a long strategy for the polluted area to keep humans and animals healthy. Phytoremediation would be an effective technique to remediate the heavy metal pollutions.  相似文献   

6.
The chemical and mineralogical composition of dry deposition in the western highlands of central and south Jordan at the end of the summer season 2000, reflect the composition of soils in addition to anthropogenic activities at these areas. Calcite predominated in the central region whereas calcite and quartz are the dominant minerals in south Jordan. The concentrations of Hg, Cr, Ni, Cu, Pb and Zn were higher in central Jordan, which might be attributed to higher anthropogenic activities than south. On the other hand, Fe, Mn, Ti, Ba, Sr, Y and Rb were higher in the south of Jordan reflecting the composition of soil at these sites. At Aqaba city, the only port of Jordan, where Cr, Cd, As and S were higher than other areas. This variation might be attributed to the contribution of phosphate dust in the atmosphere through handling processes.  相似文献   

7.
This study investigated the influence of angular exposure and distance from vehicular traffic on the diversity of epiphytic lichens and the bioaccumulation of traffic-related elements in a town of central Italy. An Index of Lichen Diversity (ILD) was calculated on the street-facing and the opposite side of road-lining trees and in a urban park 250 m away, and the content of selected trace elements (Al, Ba, Ce, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, V, and Zn) was determined in samples of the lichen Punctelia borreri (Sm.) Krog growing on tree bark, both on the exposed and opposite sides. ILD increases with distance from traffic emissions. However, at the site with vehicle traffic, non-nitrophilous lichens decreased while nitrophilous ones increased. The concentration of the traffic-related elements Ba, Cr, Cu, Mn, Sb, and Zn accumulated in thalli of P. borreri was higher on roadside trees than in trees from the urban park. ILD was not affected by the angular exposure to the road and the bioaccumulation of traffic-related elements was similar in lichens from the side of the bole exposed to traffic emissions and particulate resuspension and from the opposite side. The angular exposure in respect to the traffic source does not influence trace element accumulation. These results are important when using lichens for biomonitoring purposes, both for planning future studies and for the reliability of the interpretation of past surveys that do not report information about the angular exposure of the collected lichen material.  相似文献   

8.
Concentrations of individual polychlorinated biphenyls (PCBs) were determined in blubber, liver, kidney and brain tissues of 10 male harbour seals (Phoca vitulina) of different ages. The animals were found dead or dying on the southern coast of Norway in 1988 during the morbilli virus epizootic. Twenty-three PCB congeners were investigated in all tissues by capillary gas chromatography with electron capture detection and comparison with standards of the respective congeners (IUPAC numbers 28, 52, 74, 99, 101, 105, 110, 114, 118, 128, 138, 141, 149, 153, 156, 157, 170, 180, 183, 187, 194, 206 and 209). In addition, three toxic coplanar congeners (IUPAC numbers 77, 126 and 169) were investigated in the blubber samples. Total PCB (sum of the determined congeners) in kidney (12-60 nmol g(-1)), liver (12-90 nmol g(-1)) and blubber (10-79 nmol g(-1)) were similar on extractable lipid basis, while total PCB in brain lipid was about 1/10 (1.6-12 nmol g(-1)). The absolute concentrations of the individual congeners in brain lipid correlated poorly with the respective concentrations in each of the other tissues, while the individual congener concentrations in the lipid fractions of kidney, liver and blubber tended to correlate with each other. The relative concentrations of the sum of the most persistent congeners (PCB-99, -128, -138, -153, -170, -180, -187 and -194) correlated in all tissues, and an increase of the relative concentrations of these congeners, most distinct in blubber, with higher carcass weight, was shown. Also, total PCB in blubber correlated with carcass weight. When comparing the relative concentration patterns of individual congeners (per cent of total) in the four tissues, six congeners differed significantly between tissues, and the relative brain concentrations showed most deviation from the other tissues. The concentration of the coplanar PCBs was 1 : 1000-1 : 1000 of the total PCB concentration. The results demonstrate a lower accumulation together with a different concentration pattern in the brain as compared to other tissues.  相似文献   

9.
本文通过对高压脉冲电晕放电产生的等离子体活性物质对发动机尾气中的NO进行活化 ,研究其净化率与电压、频率、风速以及初始浓度的关系及其相互之间的影响 ,同时研究NO的产物NO2 随电压、频率、风速以及初始浓度的生成关系 ,实验表明 ,NO的净化率能够达到 5 0 %以上 ,在风速不大的条件下 ,NO转化的主要产物为NO2  相似文献   

10.
Four chiral HRGC column systems for the separation of selected organochlor pesticides and photoconversion products (heptachlor, cis- and trans-chlordane, o,p'-DDT, o,p'-DDD, and alpha-HCH) were tested. Cod hver oil and fish oil samples from different countries were comparatively analyzed. Of all these columns, the fourth was the most suitable one for the analysis of the selected compounds. The enantiomer ratios [ER] of cis-chlordane, trans-chlordane, photodieldrin, alpha-HCH, and o,p'-DDD in fish oils are nearly 1.0, while the ERs of the same substances are significantly different from 1.0 in cod liver oils. Contrary to that, the ER values of o,p'-DDT are remarkable different from 1 in the cod liver oils as well as in the fish oils.  相似文献   

11.
基于系统动力学模型的工业固废管理政策作用仿真   总被引:1,自引:0,他引:1  
基于系统动力学(SD)原理,首先对工业固体废弃物管理政策与其他各要素间的相互关系进行了分析,构建了因果关系图及流图;在此基础上建立了系统动力学(SD)方程,定义了激励因子和约束因子的概念,明确了其与系统其他各要素间的关系及相关参数的确定方法;最后以辽宁省为例进行实证研究,预测了辽宁省未来工业固体废弃物的产生量、综合利用量、处置量、排放量、贮存量、累积贮存量的变化趋势,对政府的激励和约束政策的变化对工业固体废弃物不同处理方式的作用效果进行了仿真。研究成果对政府科学制定政策,提高我国工业固体废弃物管理的研究水平具有重要理论与现实意义。  相似文献   

12.
Exclusive pristine values of As, Cd, Cr, Cu, Fe, Mn, Pb, and Zn in the Yangtze Estuary are calculated using principal components analysis (PCA) to probe the relationship between degrees of metal enrichment and their adverse biological effects. The results show that obvious differences in the degrees of metal enrichment exist when the enrichment factors are analyzed with reference background values on global, national, and local scales. Based on the low variability of aluminum, the exclusive metal background values in the estuary are obtained with PCA and are more likely to reflect the pristine contents of the abovementioned metals in the Yangtze Estuary. For the six most common metals (As, Cd, Cr, Cu, Pb, and Zn), significant correlations exist between the enrichment factors and their adverse biological effects. Arsenic shows the highest potential to cause adverse effects despite its general lack of enrichment. However, Cd is the most conservative element and is not likely to cause biological effects in the estuary.  相似文献   

13.
油气吸附剂及其改性方法   总被引:2,自引:1,他引:1  
吸附剂的性能对油气吸附分离的效果起着决定性的作用。介绍了活性炭、活性炭纤维、疏水硅胶和疏水沸石等油气吸附剂的吸附性能及改性工艺,提出了吸附剂的改性、复合吸附剂的使用、配套吸附器的开发、新型吸附剂对油气的吸附及解吸工艺将是今后研究的重点。  相似文献   

14.
Size distribution (fine and coarse fraction) and solubility distribution (extracted and residual fraction) of 20 elements (As, Ba, Be, Cd, Co, Cu, Fe, Li, Mn, Pb, Ni, Rb, S, Sb, Se, Sn, Sr, Ti, Tl, V) in atmospheric particulate matter (PM) were determined during a 5-year field study carried out in the Po Valley (peri-urban area of Ferrara, in Northern Italy). By studying the contribution of the two size fractions and the two solubility fractions to the atmospheric concentration of each element, it was possible to obtain interesting information about the variability of PM sources, to assess the role played by atmospheric stability in determining pollution episodes, and to obtain an estimate of the bio-accessible fraction. Atmospheric stability is confirmed to be one of the main causes of atmospheric pollution in this area and is to be responsible for the pronounced winter increase in both PM and elemental concentration. Long-range transport of natural and polluted air masses caused temporary increases in PM and elemental concentration, while local industrial emission seemed to play a secondary role. Regulated elements were well below their concentration limit, but many toxic elements were in the form of fine particles and soluble chemical species, more accessible to the environment, and the human body.  相似文献   

15.
废弃黑木耳菌糠特征及环境影响分析   总被引:1,自引:0,他引:1  
应用傅里叶变换红外光谱(FTIR)对废弃黑木耳菌糠的分子结构进行表征,结果表明,其含有纤维素、半纤维素、-NH及-COOH等基团。废弃黑木耳菌糠的热稳性能通过热重/微商热重(TG/DTG)进行证实,热分析表明废弃黑木耳菌糠中含有一定的吸附水和结合水,热稳定性良好。表面形貌和元素分布通过扫描电子显微镜(SEM)、电子显微镜(EM)及能谱(EDS)进行解释,废弃黑木耳菌糠表面粗糙而松散,纤维素和菌丝体互相缠绕,其O、C、N、Ca的质量分数为96.24%,Mg、K、S、P、Si、Na、Al的质量分数为3.76%。此外,对废弃黑木耳菌糠的pH、吸水倍率及N、P、K含量进行了测定,其pH为5.14,吸水倍率为466%,N为10.66mg/g,P为2.11mg/g,K为2.61mg/g。并对废弃黑木耳菌糠可能对大气、水及土壤产生的环境影响进行了分析。通过对废弃黑木耳菌糠特征系统的研究和环境影响行为的深入分析,为其综合利用和环境保护提供了理论依据。  相似文献   

16.
Vehicle gaseous emissions (NO, CO, CO2, and hydrocarbon [HC]) and driver's particle exposures (particulate matter < 1 microm [PM1], < 2.5 microm [PM2.5], and < 10 microm [PM10]) were measured using a mobile laboratory to follow a wide variety of vehicles during very heavy traffic congestion in Macao, Special Administrative Region, People's Republic of China, an urban area having one of the highest population densities in the world. The measurements were taken with high time resolution so that fluctuations in the emissions can be seen readily during vehicle acceleration, cruising, deceleration, and idling. The tests were conducted in close proximity to the vehicles, with the inlet of a five-gas analyzer mounted on the front bumper of the mobile laboratory, and the distance between the vehicles was usually within several meters. To measure the driver's particle exposures, the inlets of the particle analyzers were mounted at the height of the driver's breathing position in the mobile laboratory, with the driver's window open. A total of 178 and 113 vehicles were followed individually to determine the gaseous emission factor and the driver's particle exposures, respectively, for motorcycle, passenger car, taxi, truck, and bus. The gaseous emission factors were used to model the roadside air quality, and good correlations between the modeled and monitored CO, NO2, and nitrogen oxide (NO(x)) verified the reliability of the experiments. Compared with petrol passenger cars and petrol trucks, diesel taxies and diesel trucks emitted less CO but more NO(x). The impact of urban canyons is shown to cause a significant increase in the PM1 peak. The background concentrations contributed a significant amount of the driver's particle exposures.  相似文献   

17.
Development of mineral resources and the increasing mining waste emissions have created a series of environmental and health-related issues. Nowadays, the ecological restoration of mining tailings has become one of the urgent tasks for mine workers and environmental engineers all over the world. Aim of the present paper is to highlight the previous restoration techniques and the challenges encountered during the restoration of mine tailings. As it is a common practice that, before restoring of tailings, the site should be evaluated carefully. Studies showed that the mine tailings’ adverse properties, including excessive heavy metal concentration, acidification, improper pH value, salinization and alkalization, poor physical structure and inadequate nutrition, etc., are the major challenges of their restoration. Generally, four restoration technologies, including physical, chemical, phytoremediation, and bioremediation, are used to restore the mining tailings. The working mechanism, advantages, and disadvantages of these techniques are described in detail. In addition, selection of the suitable restoration techniques can largely be carried out by considering both the economic factors and time required. Furthermore, the ecosystem restoration is perceived to be a more promising technology for mine tailings. Therefore, this extensive review can act as a valuable reference for the researchers involved in mine tailing restoration.  相似文献   

18.
We investigated the behavioral effects of exposure to waterborne phytoestrogens in male fighting fish, Betta splendens. Adult fish were exposed to a range of concentrations of genistein, equol, beta-sitosterol, and the positive control 17beta-estradiol. The following behaviors were measured: spontaneous swimming activity, latency to respond to a perceived intruder (mirror reflection), intensity of aggressive response toward a perceived intruder, probability of constructing a nest in the presence of a female, and the size of the nest constructed. We found few changes in spontaneous swimming activity, the latency to respond to the mirror, and nest size, and modest changes in the probability of constructing a nest. There were significant decreases, however, in the intensity of aggressive behavior toward the mirror following exposure to several concentrations, including environmentally relevant ones, of 17beta-estradiol, genistein, and equol. This suggests that phytoestrogen contamination has the potential to significantly affect the behavior of free-living fishes.  相似文献   

19.
曝气充氧和人工造流技术修复河道污染水体   总被引:5,自引:1,他引:4  
基于模拟河道反应器,考察了曝气充氧及人工造流技术对污染水体的修复效果。结果表明,河道本身具有一定的自净能力,自然运行条件下对COD、TP、NH3-N和TN的去除率分别为7.44%、4.88%、5.70%和10.60%。通过对模拟河道进行曝气充氧,最佳气水比条件下对COD、TP、NH3-N和TN的去除率分别为15.33%、10.45%、6.78%和21.18%。在曝气基础上通过设置人工阻流板,对COD、TP、NH3-N和TN的去除率分别为26.82%、16.07%、9.51%和23.80%。结果初步显示,通过曝气充氧和人工造流技术的集成应用研究,对污染水体具有明显有效的修复作用。  相似文献   

20.
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