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241.
Air pollution by particulate matter is well linked with anthropogenic activities; the global economic crisis that broke out in the last year may be a proper indicator of this close relationship. Some economic indicators show the regional effects of the crisis on the Cantabria Region. The present work aims to evaluate the impact of the economic crisis on PM10 levels and composition at the major city of the region, Santander. Some metals linked to anthropogenic activities were measured at Santander and studied by Positive Matrix Factorization; this statistical analysis allowed to identify three main factors: urban background, industrial and molybdenum-related factor. The main results show that the temporal trend of the levels of the industrial tracers found in the present study are well agree with the evolution of the studied economic indicators; nevertheless, the urban background tracers and PM10 concentration levels are not well correlated with the studied economic indicators.  相似文献   
242.
Khunjar WO  Love NG 《Chemosphere》2011,82(6):917-922
The sorption of carbamazepine (CBZ), iopromide (IOP), trimethoprim (TMP) and 17α-ethinylestradiol (EE2) was evaluated using four biomass types (pure ammonia oxidizing bacterial culture, two heterotrophic enrichment cultures with varying levels of oxygenase activity, and a full-scale nitrifying activated sludge (NAS) culture). CBZ and IOP did not sorb to the four biomass types. EE2 did not sorb to the pure culture but sorbed significantly to the heterotrophic cultures and NAS. TMP sorbed to the heterotrophic cultures and NAS, and was not evaluated for the pure culture. Three floc characteristics (hydrophobicity, median particle size, organic matter content) correlated moderately well with the EE2 organic matter sorption coefficient (KOM,EE2). Zeta potential did not correlate well with KOM,EE2 but did with KOM,TMP, indicating that TMP sorption is more influenced by electrostatic factors than EE2. Once divalent cation-linked exocellular polymeric substances (EPS) were removed from flocs, EE2 and TMP sorption to the non-EPS (cellular) fraction decreased by approximately 50%. The correlation between KOM,EE2 for the non-EPS cellular fraction deteriorated while the correlation between KOM,TMP improved. EE2 seemed to sorb more strongly to EPS protein whereas TMP sorbed equally to polysaccharide and protein EPS. Attempts to develop predictive models were not successful. Pharmaceuticals that sorbed to biomass samples underwent biodegradation whereas those that did not sorb were not biodegraded, suggesting a relationship between sorption and pharmaceutical biotransformation.  相似文献   
243.
The significance of metal concentrations in marine mammals is not well understood and relating concentrations between stranded and free-ranging populations has been difficult. In order to predict liver concentrations in free-ranging dolphins, we examined concentrations of trace elements (Al, As, Ba, Be, Cd, Co, Cu, Fe, Li, Mn, Ni, Pb, Sb, Se, Sn, total Hg (THg), V, Zn) in skin and liver of stranded bottlenose dolphins (Tursiops truncatus) from the South Carolina (SC) coast and the Indian River Lagoon, Florida (FL) during 2000-2008. Significantly higher concentrations of Zn, Fe, Se, Al, Cu and THg were found in skin while liver exhibited significantly higher Cu, Fe, Mn and THg concentrations for both study sites. Mean skin concentrations of Cu and Mn were significantly higher in SC dolphins while higher concentrations of THg and V were found in FL dolphins. In addition, liver tissues in SC dolphins exhibited significantly higher As concentrations while higher Fe, Pb, Se, THg, and V levels were found in FL dolphins. Two elements (Cu and THg) showed significant age-related correlations with skin concentration while five elements (Cu, Se, THg, Zn and V) showed age-related correlations with liver concentrations. Geographic location influenced age-related accumulation of several trace elements and age-related accumulation of THg in hepatic tissue was observed for both sites to have the highest correlations (r2 = 0.90SC; r2 = 0.69FL). Mean THg concentration in liver was about 10 times higher in FL dolphins (330 μg g−1 dw) than those samples from SC dolphins (34.3 μg g−1 dw). The mean molar ratio of Hg to Se was 0.93 ± 0.32 and 1.08 ± 0.38 for SC and FL dolphins, respectively. However, the Hg:Se ratio varied with age as much lower ratios (0.2-0.4) were found in younger animals. Of the 18 measured elements, only THg was significantly correlated in skin and liver of stranded dolphins and skin of free-ranging dolphins from both sites suggesting that skin may be useful in predicting Hg concentrations in liver tissue of free-ranging dolphins. Results indicate that 33% of the stranded and 15% of the free-ranging dolphins from FL exceed the minimum 100 μg g−1 wet weight (ww) (∼400 dw) Hg threshold for hepatic damage while none from SC reached this level. Hepatic concentrations of As in SC dolphins and V in FL dolphins were also highly correlated with skin concentrations which may have some regional specificity predictive value. The present study provides the first application of trace element concentrations derived from stranded bottlenose dolphins to predict liver concentrations in free-ranging populations.  相似文献   
244.
本文论述了赣东北中生代火山岩中微量元素与稀土元素在不同岩性岩相及时空上的分布规律:潜火山岩中Au、Ag、Cu、Pb、Zn平均含量高于火山岩,尤以中酸性岩中较高,Ⅰ,Ⅱ旋回高于其他旋回。稀土元素由Ⅰ向Ⅱ旋回,由扬子地体向华夏地体,由爆发相向溢流相、潜火山岩相,由偏基性向中酸性岩演化;稀土配分模式是“L”型,火山岩物质来源于下地壳的部分熔融。  相似文献   
245.
In environmental monitoring, variables with analytically non-detected values are commonly encountered. For the statistical evaluation of these data, most of the methods that produce a less biased performance require specific computer programs. In this paper, a statistical method based on the median semi-variance (SemiV) is proposed to estimate the position and spread statistics in a dataset with single left-censoring. The performances of the SemiV method and 12 other statistical methods are evaluated using real and complete datasets. The performances of all the methods are influenced by the percentage of censored data. In general, the simple substitution and deletion methods showed biased performance, with exceptions for L/2, Inter and L/√2 methods that can be used with caution under specific conditions. In general, the SemiV method and other parametric methods showed similar performances and were less biased than other methods. The SemiV method is a simple and accurate procedure that can be used in the analysis of datasets with less than 50% of left-censored data.  相似文献   
246.
The aim of this study is to investigate the trace elements (TE) contents of potential biomonitors in a historical Zn–Pb mining district: apiary products (honey, royal-jelly and beeswax) lichen and moss were sampled and analysed. In spite of high TE concentrations in mining waste and soil, apiary products are free of TE contamination originating from historical mining. Lichen/moss show high TE levels, which suggest atmospheric input of local dust. Pb isotopes analysis proved the origin of TE found in lichen/moss to be mainly mining waste. These results help discuss the choice of relevant organisms for monitoring TE in the environment and bring additional data on the potential impacts of brownfields left after mining, especially on food products from apiaries.  相似文献   
247.
The attenuation of bulk organic matter and trace organic contaminants (TOrCs) was evaluated for various aquifer recharge and recovery (ARR)-ozone (O3) hybrid treatment process combinations using soil-batch reactor and bench-scale ozonation experiments as a proof of concept prior to pilot and/or field studies. In water reclamation and especially potable reuse, refractory bulk organic matter and TOrCs are of potential health concern in recycled waters. In this study, the role of biotransformation of bulk organic matter and TOrCs was investigated considering different simulated treatment combinations, including soil passage (ARR) alone, ARR after ozonation (O3-ARR), and ARR prior to ozonation (ARR-O3). During oxic (aerobic) ARR simulations, soluble microbial-like substances (e.g., higher molecular weight polysaccharides and proteins) were easily removed while (lower molecular weight) humic substances and aromatic organic matter were not efficiently removed. During ARR-ozone treatment simulations, removals of bulk organic matter and TOrCs were rapid and effective compared to ARR alone. A higher reduction of effluent-derived organic matter, including aromatic organic matter and humic substances, was observed in the ARR-O3 hybrid followed by the O3-ARR hybrid. An enhanced attenuation of recalcitrant TOrCs was observed while increasing the ozone dose slightly (O3: DOC = 1). TOrC removal efficiency also increased during the post-ozone treatment combination (i.e., ARR-O3). In addition, the carcinogenic wastewater disinfection byproduct N-nitrosodimethylamine (NDMA) was eliminated below the method reporting limit (<5 ng L−1) both during ARR treatment alone and the ARR-ozone hybrid.  相似文献   
248.
Seasonal variation of the concentrations of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were measured by ICP-AES in the water and sediment from the Saricay Stream, Geyik Dam and Ortakoy Well in the same basin. Comparisons between trace metal concentrations in water and sediment in three sources (Stream, Dam and Well) were made. The concentrations of a large number of trace metals in the water and sediment were generally higher in the Stream than in the Well and Dam, particularly in summer. Trace metal concentration ranges in sediments of the Saricay Stream and its sources showed very wide ranges (as mass ratio): Co: 5–476 μg g−1, Cr: 15–1308 μg g−1, Cu: 7–128 μg g−1, Fe: 1120–13210 μg g−1, Mn: 150–2613 μg g−1, Ni: 102–390 μg g−1, Pb: 0.7–31.3 μg g−1 and Zn: 18–304 μg g−1, whereas Cd was not detected. Trace metal concentration ranges found in waters were: Co: 9.5–20.7 μg L−1, Cr: 20.3–284 μg L−1, Cu: 170–840 μg L−1, Fe: 176–1830 μg L−1, Mn: 29.3–387 μg L−1, and Ni: 4.3–21.9 μg L−1. Among the trace metals studied, Cd and Zn in two seasons and Pb in winter were usually not detected or in the recommended levels. In addition, Cd was not detected in the sediment during the winter season. The analysis of variance (one-way ANOVA) and correlation matrix was employed for the sediment and water samples of the two field surveys (summer and winter) comparison. The three sources showed differences in metal contents. The metal levels in sediments displayed marked seasonal and regional variations, which were attributed to anthropogenic influences and natural processes. In the Saricay Stream, high values of metals during the dry season showed an anthropological effect from small industry firms, e.g.: an olive mill and a dairy farm or water dilution during summer seasons. Finally, the pollution in this basin probably originated from small industrial, low quality coal-burned thermal power plants, and particularly agricultural and domestic waste discharges.  相似文献   
249.
Rain water samples were collected to study the chemical composition of wet atmospheric precipitation (first event) over the Lucknow city in the northern Indo-gangetic alluvial plains. The samples were collected in the month of July, 2005 from different sites. The wet precipitation samples were analyzed for pH, EC, major ions (, Cl, , , , F, Na+, K+, Ca2+, Mg2+, ) and heavy metals (As, Cd, Al, Co, Cr, Cu, Fe, Mn, Mo, Ni, Hg, Pb, Se, Sn, Ti, V, Zn). The pH values of wet precipitation samples ranged between 6.5 and 8.7. The analysis of linear regression applied to the set of studied variables and computation of neutralization factors showed that neutralization occurred in precipitation samples and Ca2+ had the maximum neutralization capacity. It was found that Cl, , Ca2+, Mg2+, Na+ and K+ in the precipitation samples originated mainly from crustal/anthropogenic sources in the region. On an average Fe, and Al accounted for >72% of the total concentration of trace metals in the wet precipitation samples followed by Zn (>10%). Enrichment factors calculated for heavy metals over reference background level in seawater and Earth’s crust showed relatively higher enrichment of Zn. The principal component analysis (PCA) identified the possible sources of ionic species and heavy metals in the wet precipitation samples.  相似文献   
250.
The present study deals with the effect of fireworks on ambient air quality during Diwali Festival in Lucknow City. In this study, PM10, SO2, NO x and 10 trace metals associated with PM10 were estimated at four representative locations, during day and night times for Pre Diwali (day before Diwali) and Diwali day. On Diwali day 24 h average concentration of PM10, SO2, and NO x was found to be 753.3, 139.1, and 107.3 μg m−3, respectively, and these concentrations were found to be higher at 2.49 and 5.67 times for PM10, 1.95 and 6.59 times for SO2 and 1.79 and 2.69 for NO x , when compared with the respective concentration of Pre Diwali and normal day, respectively. On Diwali day, 24 h values for PM10, SO2, and NO x were found to be higher than prescribed limit of National Ambient Air Quality Standard (NAAQS), and exceptionally high (7.53 times) for PM10. On Diwali night (12 h) mean level of PM10, SO2 and NO x was 1,206.2, 205.4 and 149.0 μg m−3, respectively, which was 4.02, 2.82 and 2.27 times higher than their respective daytime concentrations and showed strong correlations (p < 0.01) with each other. The 24 h mean concentration of metals associated with PM10 was found to be in the order of Ca (3,169.44) > Fe (747.23) > Zn (542.62) > Cu (454.03), > Pb (307.54) > Mn (83.90) > Co (78.69) > Cr (42.10) > Ni (41.47) > Cd (34.69) in ng m−3 and all these values were found to be higher than the Pre Diwali (except Fe) and normal day. The metal concentrations on Diwali day were found to be significantly different than normal day (except Fe & Cu). The concentrations of Co, Ni, Cr and Cd on Diwali night were found to be significantly higher than daytime concentrations for Pre Diwali (control). The inter correlation of metals between Ca with Pb, Zn with Ni and Cr, Cu with Co, Co with Mn, Ni with Cd, Mn with Cd, Ni with Cd and Cr, and Cr with Cd showed significant relation either at p < 0.05 or P < 0.01 levels, which indicated that their sources were the same. The metals Cu, Co, Ni, Cr and Cd showed significant (p < 0.01) association with PM10. These results indicate that fireworks during Diwali festival affected the ambient air quality adversely due to emission and accumulation of PM10, SO2, NO x and trace metals. ITRC Communication Number 2538  相似文献   
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