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We performed a trace analytical study covering nine hormonally active UV-filters by LC-MS/MS and GC-MS in river water and biota. Water was analysed at 10 sites above and below wastewater treatment plants in the river Glatt using polar organic chemical integrative samplers (POCIS). Four UV-filters occurred in the following order of decreasing concentrations; benzophenone-4 (BP-4) > benzophenone-3 (BP-3) > 3-(4-methyl)benzylidene-camphor (4-MBC) > 2-ethyl-hexyl-4-trimethoxycinnamate (EHMC). BP-4 ranged from 0.27 to 24.0 μg/POCIS, BP-3, 4-MBC and EHMC up to 0.1 μg/POCIS. Wastewater was the most important source. Levels decreased with higher river water flow. No significant in-stream removal occurred. BP-3, 4-MBC and EHMC were between 6 and 68 ng/L in river water. EHMC was accumulated in biota. In all 48 macroinvertebrate and fish samples from six rivers lipid-weighted EHMC occurred up to 337 ng/g, and up to 701 ng/g in 5 cormorants, suggesting food-chain accumulation. UV-filters are found to be ubiquitous in aquatic systems. 相似文献
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介绍了北仑发电厂5×600 MW机组烟气脱硫项目石灰石粉双套管长距离气力输送工程的系统设计、安装、调试、运行等情况,并分析了该系统的主要特点. 相似文献
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Maria Rutkowska Katarzyna Krasowska Aleksandra Heimowska Grażyna Adamus Michał Sobota Marta Musioł Henryk Janeczek Wanda Sikorska Andrej Krzan Ema Žagar Marek Kowalczuk 《Journal of Polymers and the Environment》2008,16(3):183-191
Degradation of atactic poly[(R,S)-3-hydroxybutyrate] (a-PHB) binary blends with natural poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV, 12 mol% of 3HV units), has been investigated and compared with plain PHBV in the compost containing
activated sludge and under marine exposure conditions in the dynamic water of the Baltic Sea. Characteristic parameters of
compost and the Baltic Sea water were monitored during the incubation period (6 weeks) and their influence on the degree of
biodegradation is discussed. After specified degradation times of the experiments the weight loss of the samples, surface
changes, changes in molecular weight and polydispersity as well as changes of the composition and thermo-mechanical properties
of the blends have been evaluated. Macroscopic observations of the samples were accompanied by investigations using optical
microscopy, size-exclusion chromatography (SEC), nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC)
and tensile testing. The degree of degradation of blends of a-PHB with PHBV depends on the blend composition and environmental
conditions. In both environments studied the weight loss of plain PHBV was more significant than changes the molecular weight.
In both environments only enzymatic degradation of the blends, which proceeds via surface erosion mechanisms, was observed
during the incubation period. 相似文献
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中国西北地区水资源的开发和利用 总被引:2,自引:0,他引:2
我国西北地区地广人稀,水资源比较贫乏,而且时空分布极不均匀,极大地影响了该地区人民的生活,限制了该地区的经济开发,因此大力开发西北地区面临的首要问题即水资源问题。本文从西北地区水资源的自然分布、开发利用水资源中存在的问题及有效的解决途径三方面进行了简要的综述。 相似文献
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