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111.
Laboratory tests were conducted to compare the effects of various concentrations of lindane and deltamethrin on mature earthworms (Eisenia fetida) cultured in artificial soil during typical acute (14d) and subchronic (42d) exposure periods. The effects of the two pesticides on earthworm mortality, growth inhibition, and cellulase activity were determined for different exposure durations. The toxicity order for earthworm mortality from the 14-day exposure was lindane > deltamethrin, with median lethal concentrations (LC50) of 162.1 and 432.9 mg kg−1, respectively. Earthworms exposed to deltamethrin showed dose-dependent toxic effects on growth and cellulase activity only from the acute exposures, whereas lindane’s effects on these activities were seen correlated with both the acute and subchronic doses. Also, changes in biomass and cellulase activity during the subchronic exposure period appear to be a more sensitive parameter than the LC50 value in assessing pesticidal injury.  相似文献   
112.
在分析硝基氯苯生产废水中有机污染物的基础上,研究了四种典型污染物即硝基苯、对氯硝基苯、邻氯硝基苯、对硝基酚对好氧/厌氧污泥的生物毒性,硝基苯类化合物的厌氧、好氧生物降解过程和特性,同时初步探索了SBR工艺处理该生产废水的可行性  相似文献   
113.
有机污染物的植物修复   总被引:1,自引:0,他引:1  
(山西农业大学农业生物工程中心,山西太谷 030801)  相似文献   
114.
The study aim was to determine whether enhanced dry deposition of acidic atmospheric pollutants by broadleaf woodland expansion could increase the potential for acidification of surface waters in acid-sensitive areas. Dry sulphur (S) and nitrogen (N) deposition was modelled with the Fine Resolution Atmospheric Multi-pollutant Exchange (FRAME) model using a roughness length value calculated specifically for birchwoods. Two scenarios were investigated for an acid-sensitive area in Scotland where broadleaf woodland expansion, mainly as birchwood, is occurring: (1) 2002 emissions and broadleaf woodland cover of 5.6%; (2) 2020 projected emissions and broadleaf cover of 29%. The roughness length calculated for birch with Raupach’s simplified drag-partition model was 0.73 m, lower than the value of 1.0 m for conifers which is the default for forest land cover in FRAME. Modelled dry S and N deposition increased between 2002 and 2020 from 8.7 to 29 × 10−3 keq ha−1 year−1 of H+. However, modelled total dry and wet non-marine S and N deposition decreased during the same period from 1070 to 682 × 10−3 keq ha−1 year−1 of H+ due to the lower projected emissions in 2020 and the dominance of wet deposition in the remote and upland study area (mean annual rainfall 2275 mm). The modelled total non-marine S and N deposition was used to calculate streamwater critical loads exceedance with the First-order Acidity Balance (FAB) model for five catchments in the study area. The modelled deposition for both the 2002 and 2020 scenarios was less than the calculated streamwater critical loads so the catchments were not considered at risk of streamwater acidification under the projected future emissions and increased broadleaf woodland cover. Nevertheless, broadleaf expansion could pose a greater risk of acidification in acid-sensitive areas with lower rainfall, closer to pollutant sources, where dry deposition accounts for a higher proportion of total S and N deposition.  相似文献   
115.
水环境中的弱极性痕量有机污染物定量分析通常需要采集大体积水样,针对此大体积水样采集受到运输、空间、污染等因素影响的缺点,研制了一种大体积水样原位采集富集装置,直接将采集水样就地处理.该装置主要由蠕动泵、滤膜托盘、支撑柱、卡箍、压力阀、吸附材料套筒和流量计组成.该采样装置使用简单,操作方便,能够实现大体积水样原位采集富集,适合于大规模弱极性痕量有机污染物环境调查样品的采集和富集.  相似文献   
116.
为优化橡胶木粉/回收聚乙烯复合材料生产工艺配方,以马来酸酐接枝聚丙烯( MAPP)和铝酸酯作为偶联剂,调节配方组成制备了3组木塑复合材料试件,对试件的弯曲破坏载荷、吸水性能进行测定,并观察其断面的相容性,结果表明,以MAPP作为偶联剂的试样性能优于使用铝酸酯的试样,同时无机填料添加剂量的适当下调也有利于材料性能的提升,并通过断面分析印证了材料内部界面相互作用越强则复合材料性能也越好。  相似文献   
117.
曹东冬 《拖拉机》2014,(6):40-42
在经过改造的单缸柴油机上对PRF87、PRF93、TRF25这3种汽油替代物在中、低负荷时进行了低温模式的燃烧物排放研究。试验表明,TRF25在中、低负荷工况下的燃烧物排放特性与汽油吻合较好,且炭烟排放极低,体现出在低温燃烧模式下燃用高辛烷值汽油特性燃料在降低炭烟排放方面的巨大潜力。  相似文献   
118.
Brucellosis, a worldwide zoonosis, is linked to reproductive problems in primary hosts. A high proportion of Brucella-positive hooded seals (Cystophora cristata) have been detected in the declined Northeast Atlantic stock. High concentrations of polychlorinated biphenyls (PCBs) have also been discovered in top predators in the Arctic, including the hooded seal, PCB 153 being most abundant. The aim of this study was to assess the pathogenicity of Brucella pinnipedialis hooded seal strain in the mouse model and to evaluate the outcome of Brucella spp. infection after exposure of mice to PCB 153. BALB/c mice were infected with B. pinnipedialis hooded seal strain or Brucella suis 1330, and half from each group was exposed to PCB 153 through the diet. B. pinnipedialis showed a reduced pathogenicity in the mouse model as compared to B. suis 1330. Exposure to PCB 153 affected neither the immunological parameters, nor the outcome of the infection. Altogether this indicates that it is unlikely that B. pinnipedialis contribute to the decline of hooded seals in the Northeast Atlantic.  相似文献   
119.
项丽 《安徽农学通报》2008,14(21):76-77
随着对纳米碳管研究的不断深入,对碳纳米管的应用研究越来越受到人们的重视。本文主要对应用碳纳米管萃取环境中有机污染物的研究进展作一综述,并对其在此领域的应用前景进行了展望。  相似文献   
120.
多酸(盐)化合物因独特的结构及光谱性质,作为一类光催化剂受到人们的青睐,概述了多酸(盐)光催化氧化处理有机污染物的研究进展。  相似文献   
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