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41.
《Journal of environmental science and health. Part. B》2013,48(5-6):791-803
Abstract The effects of Fe(II), Mn(II) and humic substances on the catalyzed ozonation of alachlor, an endocrine disruptor were investigated. Results revealed that small amounts of Fe(II), Mn(II), and humic substances could enhance the ozonation of alachlor, but larger amounts of them would retard the oxidation. These results were successfully identified by an electron paramagnetic resonance (EPR) spectroscopy/spin-trapping method that could quantify hydroxyl radicals. The production of hydroxyl radicals was obviously increased with the increasing of Fe(II) concentration, which contributed to enhance ozonation at low concentrations. But the excess Fe(II) consumed some of the radicals when it was added at a higher concentration (1.5 mg/L). However, no obvious radicals were observed when a different amount of Mn(II) was used, and the catalytic ozonation of alachlor by Mn(II) mainly followed the mechanism of “active sites created on the surface of MnO2.” The radical pathway was followed when alachlor was ozonated with different concentrations of humic substances because of its radical initiating, promoting, and inhibiting effects. 相似文献
42.
四平市二龙湖底泥磷释放研究 总被引:6,自引:0,他引:6
采用室内实验模拟法对四平市二龙湖富营养化限制因子磷的底泥释放速率及释放量进行了研究,并研究在种环境因子(温度、pH、DO和扰动因素)影响下底泥磷的释放规律。结果表明,(1)二龙湖年平均底泥释磷量为208·78g,最大释磷率为0·889μg/g(T=20℃,pH=8,DO为4·68mg/L);(2)自然和人为的扰动因素会促进底泥的磷释放;(3)H在弱酸至中性范围内底泥释磷量最小,酸性和碱性条件都有利于磷的释放;(4)随着温度的升高底泥释磷量增大;(5)厌条件比好氧条件更有利于磷的释放。 相似文献
43.
Pollution characteristics of 23 veterinary antibiotics in livestock manure and manure-amended soils in Jiangsu province,China 总被引:3,自引:0,他引:3
Xin Y. Guo Li J. Hao Pan Z. Qiu Rong Chen Jing Xu Xiang J. Kong 《Journal of environmental science and health. Part. B》2016,51(6):383-392
The aim of this study was to investigate the pollution characteristics of typical veterinary antibiotics in manure and soil of livestock farms in Jiangsu province. This investigation employed solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A total of 53 manure and 50 amended soil samples from 16 livestock farms in Jiangsu province were collected for analysis. In the manure samples, the highest detected frequencies and concentrations were those of tetracyclines (TCs, 54.1 ± 5775.6 μgkg?1), followed by fluoroquinolones (FQs, 8.4 ± 435.6 μgkg?1), sulphonamides (SAs, 3.2 ± 5.2 μgkg?1) and macrolides (MACs, 0.4 ± 110.5 μgkg?1). Statistical analysis was used to illuminate the pollution characteristics of 23 veterinary antibiotics for various animal types and different regions in Jiangsu province. The results showed that the pollution level in cow manure was relatively lower compared with pig and chicken manure due to the relative restriction of medication. Furthermore, contamination was serious in amended soil from chicken farms. The pollution level in manure among different regions was higher to the south and north compared with the centre of the region. The same outcome was found for soil. Antibiotic residues in organic fertilizer were also investigated in this study. We found that although the detected concentration was lower in organic fertilizer than in fresh manure, detection frequencies (10–90%) were high, especially for roxithromycin (90%) in MACs (30–90%). This finding suggests attention should be paid to the pollution levels in organic fertilizer. This study is the first extensive investigation of the occurrence and distribution of many kinds of typical veterinary antibiotics in manure and soil from livestock farms of Jiangsu province. This investigation systematically assesses veterinary antibiotics usage and related emissions in southeast China. 相似文献
44.
用超细玻璃纤维滤膜采集杭州市某道路上机动车排放的苯并(a)芘,经超声萃取,高速离心后直接进HPLC分析。在选定的色谱条件下,苯并(a)芘与其他多环芳烃完全分离,绝对进样量在0.8~0.02 ng时线性良好,相关系数为0.99979,最小检出量0.8 pg,加标回收率87.5%~93.8%。 相似文献
45.
Adsorption of Pb(II) on variable charge soils amended with rice-straw derived biochar 总被引:11,自引:0,他引:11
Two Ultisols and one Oxisol from tropical regions of southern China were incubated with rice straw biochar to investigate the effect of biochar on their surface charge and Pb(II) adsorption using batch methods. The incorporation of biochar induced a remarkable increase in soil cation exchange capacity after 30 d of incubation. The incorporation of biochar significantly increased the adsorption of Pb(II) by these variable charge soils; the enhancement of adsorption of Pb(II) by these soils increased with the addition level of biochar. Adsorption of Pb(II) involved both electrostatic and non-electrostatic mechanisms; however, biochar mainly increased Pb(II) adsorption through the non-electrostatic mechanism via the formation of surface complexes between Pb2+ and functional groups on biochar. There was greater enhancement of biochar on the non-electrostatic adsorption of Pb(II) by the variable charge soils at relatively low pH. Therefore, the incorporation of biochar decreased the activity and availability of Pb(II) to plants through increased non-electrostatic adsorption of Pb(II) by acidic variable charge soils. 相似文献
46.
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48.
Effective EU and Member State policies for stimulating CCS 总被引:1,自引:0,他引:1
Although CO2 capture and storage (CCS) is widely recognised as an option to mitigate climate change, consistent and effective EU policies to advance CCS are still absent. This paper discusses policy instruments for advancing large-scale deployment of CCS in the European Union, and evaluates them in a multi-criteria analysis. The EU Emissions Trading Scheme (EU-ETS) is a cost-effective instrument for limiting greenhouse gas emissions, but it is questionable whether its currently limited time horizon and short-trading periods will lead to substantial CCS diffusion. Complementary policies at the EU and the Member State level may repair this and provide sufficient incentives for CCS. Potential policies include financial instruments such as investment subsidies, a feed-in scheme, or a CO2 price guarantee, as well as a CCS mandate or a low-carbon portfolio. These policy options differ with respect to their environmental effectiveness, possible interaction with the EU-ETS, costs and financial risk involved, and their competition with other mitigation options. Interactions between Member State policies and the EU-ETS are smaller in scope than those of EU-wide policies, but they are more likely to lead to displacement of financial resources from other low-carbon technologies. In addition, national policies may pose a significant part of the financial risk of CCS operations with Member States, reducing the operator's incentive to innovate. Overall, structural policies at the EU level, such as a mandate or a low-carbon portfolio standard would be more conducive for realising large-scale deployment of CCS across the EU as well as more acceptable to environmental organisations. 相似文献
49.
Banerjee A Nayak D Chakrabortty D Lahiri S 《Environmental pollution (Barking, Essex : 1987)》2008,151(2):423-427
Attempt has been made to study the accumulation behaviour of a common plant, Mung bean (Vigna radiata) towards Cr(III) and Cr(VI) to have an insight on the migration and bio-magnification of Cr. For this purpose healthy germinated Mung bean seeds were sown in the sand in the presence of Hoagland's nutrient solution containing measured amount of K(2)(51)Cr(2)O(7) and (51)Cr(NO(3))(3).9H(2)O. Growth rate was also studied in the presence and absence of phosphate salts in the medium. It has been found that the transfer of chromium from soil to plant is significantly low (maximum 5% for both Cr(III) and Cr(VI)). Maximum accumulation of Cr occurs in the root with respect to the total chromium accumulation by the plant. Other parts of the Mung bean plant, e.g. cotyledons, shoot and leaves, show negligible accumulation. Therefore, the chance of direct intake of Cr through food as well as through the grazing animals to human body is less. 相似文献
50.
Seasonal concentrations and partitioning of PAHs in a suburban site of Bursa, Turkey 总被引:3,自引:0,他引:3
Effects of space heating on atmospheric concentrations and gas-particle partitioning of PAHs were investigated in a suburban site of Bursa, Turkey. The average concentrations of ∑15-PAHs in heating season samples were approximately 10 times higher than those of non-heating season samples. The plot of log Kp versus log PL0 for all the data set gave significantly different slopes. The slope for the heating season (−0.75) samples was steeper than the one for the non-heating season (−0.64) samples. It was also observed that partitioning of PAHs for the non-heating season samples showed different characteristics depending on air parcel trajectories. Generally steeper slopes were obtained for the air parcels traveled across the Black sea and arrived to the sampling site from northern sector. On the other hand, the variations in slopes according to air mass origin were insignificant for the heating season samples. Local contributions from space heating are the reason for this observation. 相似文献