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Species- and tissue-specific accumulation of Dechlorane Plus in three terrestrial passerine bird species from the Pearl River Delta, South China 总被引:1,自引:0,他引:1
Little data is available on the bioaccumulation of Dechlorane Plus (DP) in terrestrial organisms. Three terrestrial passerine bird species, light-vented bulbul, long-tailed shrike, and oriental magpie-robin, were collected from rural and urban sites in the Pearl River Delta to analyze for the presence of DP and its dechlorinated products in muscle and liver tissues. The relationships between trophic level and concentration and isomeric composition of DP in birds were also investigated based on stable nitrogen isotope analysis. DP levels had a wide range from 3.9 to 930 ng g−1 lipid weight (lw) in muscle and from 7.0 to 1300 ng g−1 lw in liver. Anti-Cl11-DP and syn-Cl11-DP, two dechlorinated products of DP, were also detected in bird samples with concentrations ranged between not detected (nd)-41 and nd-7.6 ng g−1 lw, respectively. DP preferentially accumulated in liver rather than in muscle for all three bird species. Birds had significantly higher concentrations of DP in urban sites than in rural sites (mean, 300 vs 73 ng g−1 lw). The fractions of anti-DP (fanti) were higher in birds collected in rural sites than in urban sites. Significant positive correlation between DP levels and δ15N values but significant negative correlation between fanti and δ15N values were found for birds in both urban and rural sites, indicating that trophic level of birds play an important role in determining DP level and isomeric profile. 相似文献
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利用Aspen Plus软件平台建立了生物质燃烧模型,对燃烧中NOx的生成进行了模拟计算,计算结果与已有文献的试验结果较好地相符.在此基础上,研究了燃烧温度和过量空气系数对生物质燃烧NOx生成的影响规律.结果表明,生物质燃烧过程中NOx的生成量随温度和过量空气系数的增长而快速增长;应用Aspen Plus模拟生物质燃烧具有一定的可行性,而且其模型参数设置较为灵活,能够对多种生物质的燃烧进行热力学分析,可为生物质清洁燃烧技术提供有益参考. 相似文献
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本文对工程项目大气环境影响评价中污染物浓度叠加方法进行了研究。在叠加方法研究中,提出用判别指数判别筛选叠加方法。通过叠加方法筛选,选取了瞬时浓度,日均浓度叠加方法。经实例验证,证明方法是合理可行的,适用于大气污染物浓度叠加计算。 相似文献
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PTA废水厌氧处理工程实例类比研究 总被引:1,自引:0,他引:1
文中介绍了PTA废水厌氧处理中目前国内普遍采用的厌氧(UASB)工艺.厌氧(UASB)工艺对PTA废水进行处理,不需要动力提供氧源,动力消耗低,可降低废水处理成本.厌氧(UASB)反应器的关键就是将反应器中的气固液进行三相分离,并保持反应器污泥的颗粒化.从工程实例的运行中概述了经典UASB反应器、新型UASB反应器和UASB Plus反应器的特点. 相似文献
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Levels and isomer profiles of Dechlorane Plus in the surface soils from e-waste recycling areas and industrial areas in South China 总被引:3,自引:0,他引:3
Zhiqiang Yu Shutao Gao Jingzhi Wang Huiru Li Xiangying Zeng Jiamo Fu 《Environmental pollution (Barking, Essex : 1987)》2010,158(9):2920-2925
Dechlorane Plus (DP) is a highly chlorinated flame retardant. Levels of DP were measured in surface soils from e-waste recycling areas and industrial areas in South China. Higher DP levels were found in e-waste recycling areas (undetectable-47.4 ng/g) than those in industrial areas (0.0336-4.65 ng/g) in South China. The highest DP concentration (3327 ng/g) was found at the e-waste recycling site in Qingyuan, while DP levels fell dramatically with increasing distance away from the recycling site, suggesting that the e-waste recycling activities are an important source of DP emissions. The mean ratios of anti-DP to total DP (fanti) for different sampling areas ranged from 0.58 to 0.76 and showed no significant difference from the ratio for the technical DP products (t-test, p > 0.05). Further intensive studies are needed to investigate the process of DP degradation and its degradation products. 相似文献
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得克隆(Dechlorane Plus,DP)作为全球广泛使用的氯代阻燃剂,具有POPs特性和环境毒性,但其生物毒性数据非常有限。本文选择水生初级生产者纤细裸藻(Euglena gracilis)作为研究对象,通过检测藻细胞生长状况、光合色素水平、抗氧化酶活性、谷胱甘肽(GSH)和丙二醛(MDA)含量变化,研究了不同浓度DP对其生态毒性效应的影响。结果显示,低浓度DP对纤细裸藻生长具有一定促进作用,但差异不显著;DP浓度较低时(0.1和0.5 mg·L-1DP)类胡萝卜素含量受到轻微抑制;较高浓度DP暴露导致超氧化物歧化酶(SOD)、过氧化物酶(POD)和谷胱甘肽(GSH)水平显著增加,同时高浓度DP(8 mg·L-1)下MDA含量显著上升,提示膜结构受到损伤;表明较高实验浓度范围内,DP对纤细裸藻的生长及抗氧化系统均产生一定影响,结果将为DP的环境生态风险评价提供科学依据。 相似文献
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Dechlorane Plus (DP) in air and plants at an electronic waste (e-waste) site in South China 总被引:1,自引:0,他引:1
Chen SJ Tian M Wang J Shi T Luo Y Luo XJ Mai BX 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1290-1296
Air and foliage samples (Eucalyptus spp. and Pinus massoniana Lamb.) were collected from e-waste and reference sites in South China and analyzed for Dechlorane Plus (DP) and two dechlorinated DPs. DP concentrations in the air were 13.1-1794 pg/m3 for the e-waste site and 0.47-35.7 pg/m3 for the reference site, suggesting the recycling of e-waste is an important source of DP to the environment. Plant DP, with concentrations of 0.45-51.9 ng/g dry weight at the e-waste site and 0.09-2.46 ng/g at the reference site, exhibited temporal patterns similar to the air DP except for pine needle at the reference site. The air-plant exchange of DP could be described with the two-compartment model. Anti-Cl11 DP was measured in most air and plant samples from the e-waste site. The ratios of anti-Cl11 DP to anti-DP in the air and plants may indicate the preferential uptake of dechlorinated DP by plant compared with DP. 相似文献
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为评估淮安市大气中DP(德克隆)的水平及分布特征,于2016—2018年采用大气被动采样方法,共收集了96个大气样品,对大气中ρ(DP)、ρ(syn-DP)(syn-DP为顺式DP)和ρ(anti-DP)(anti-DP为反式DP)进行分析,结合fsyn〔ρ(syn-DP)占ρ(DP)的比例〕分布模式,追溯大气中DP的迁移转化规律.结果表明:①所有样品中均检出DP,厂界内大气中ρ(DP)范围为1 925~4 221 pg/m3,平均值为3 053 pg/m3;除厂界内采样点外,其他采样点大气中ρ(DP)范围为9~92 pg/m3,平均值为42 pg/m3.②ρ(DP)最高值出现在厂界内采样点,其ρ(DP)比厂界外采样点高约3个数量级.③大气中ρ(DP)分布受季节性影响较为明显,呈冬季高、夏季低的特征.④厂界内采样点fsyn平均值为0.26,厂界外采样点的fsyn值在0.18~0.53之间,平均值为0.28,与厂界内采样点大气中DP的fsyn平均值相当.研究显示,淮安市大气中的高水平DP主要来源于DP生产,fsyn值受季节和空间变化的影响. 相似文献