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101.
海水中有机污染物的气相色谱-质谱法鉴定   总被引:5,自引:0,他引:5  
本文采用一种简便的连续萃取装置.对海水中痕量有机物进行富集,大量的海水被萃取后,萃取物经干燥浓缩在毛细管气相色谱上进行了分离,并用质谱-计算机自动检索装置进行了定性鉴定,共确定出36种组分。本方法的检测限为辛烷10ppt。  相似文献   
102.
The self-organising map approach was used to assess the efficiency of chlorinated solvent removal from petrochemical wastewater in a refinery wastewater treatment plant. Chlorinated solvents and inorganic anions (11 variables) were determined in 72 wastewater samples, collected from three different purification streams. The classification of variables identified technical solvents, brine from oil desalting and runoff sulphates as pollution sources in the refinery, affecting the quality of wastewater treatment plant influent. The classification of samples revealed the formation of five clusters: the first three clusters contained samples collected from the drainage water, process water and oiled rainwater treatment streams. The fourth cluster consisted mainly of samples collected after biological treatment, and the fifth one of samples collected after an unusual event. SOM analysis showed that the biological treatment step significantly reduced concentrations of chlorinated solvents in wastewater.  相似文献   
103.
将新洋港分为3段,分别对各段的生活、农业、工业污染源进行调查,分析了污染特征。根据社会经济发展情况预测了2012年和2015年的入河污染物总量。综合考虑水文水质和功能区等因素,采用模型计算了2012年和2015年的水环境容量,根据结果制定了新洋港入河污染物总量控制目标。  相似文献   
104.
珠江三角洲蔬菜基地蔬菜中邻苯二甲酸酯的含量特征   总被引:2,自引:0,他引:2  
邻苯二甲酸酯是一类重要的环境激素类污染物。本文以气相色谱/质谱(GC/MS)联用检测技术,对珠江三角洲地区典型蔬菜生产基地蔬菜中6种邻苯二甲酸酯化合物进行测试分析。结果发现:(1)珠江三角洲地区典型蔬菜生产基地的蔬菜样品中,多数样品检测出6种邻苯二甲酸酯,总含量为0.46~12.02mg/kg。(2)基地蔬菜中单个邻苯二甲酸酯化合物的种类和含量因蔬菜种类、品种、部位和生长环境等因素而异。(3)同种类蔬菜在不同基地或同一基地不同种类蔬菜中邻苯二甲酸酯的含量分布不同。(4)大部分蔬菜中以邻苯二甲酸正二丁酯(DnBP)和邻苯二甲酸双(2-乙基己基)酯(DEHP)为主。  相似文献   
105.
环境污染物的影子价格体现了污染物的边际减排成本,是政府制定公共环境政策的重要依据。本文在环境技术的基础上,扩展了传统的产出方向性距离函数方法,进而构建了能够将多种环境污染物的影子价格进行综合估测新的影子价格模型。采用这种新的模型方法和安徽煤炭开采和洗选企业的样本数据,对煤炭资源开采利用过程中排放的三种主要环境污染物——废水、废气和固体废物的影子价格进行了估计。结果发现,2009年,安徽煤炭开采和洗选企业所排放的废水、废气和固体废物的平均影子价格分别为0.021 6万元/t、0.031 37万元/t和0.178 48万元/t。这三种环境污染物的影子价格存在差异,反映出安徽煤炭开采企业处理不同环境污染物所面临的环境成本是不同的。环境行为监管者在做出环境规制决策前要充分考虑到这个前提。  相似文献   
106.
洹河水中痕量有机污染物的研究   总被引:6,自引:2,他引:4  
采用固相萃取技术 ,对洹河水中痕量有机物进行富集 ,大量的地表水被 C1 8键合相萃取后 ,洗脱液经干燥浓缩用于 GC和 GC/MS分析 ,鉴定出 64种有机物 ,并对苯系物、杂环类等 2 7种主要污染物作了定量测定 ,得出有机物的沿途变化规律。  相似文献   
107.
Organochlorine (OC) contaminants are transported to the Polar Regions, where they have the potential to bioaccumulate, presenting a threat to the health of wildlife and indigenous communities. They deposit onto snowpack during winter, and accumulate until spring, when they experience prolonged solar irradiation until snowmelt occurs. Photochemical degradation rates for aldrin and dieldrin, in frozen aqueous solution made from MilliQ water, 500 μM hydrogen peroxide solution or locally-collected melted snow were measured in a field campaign near Barrow, AK, during spring-summer 2008. Significant photoprocessing of both pesticides occurs; the reactions depend on temperature, depth within the snowpack and whether the predominant phase is ice or liquid water. The effect of species present in natural snowpack is comparable to 500 μM hydrogen peroxide, pointing to the potential significance of snowpack-mediated reactions. Aldrin samples frozen at near 0 °C were more reactive than comparable liquid samples, implying that the microenvironments experienced on frozen ice surfaces are an important consideration.  相似文献   
108.
Levels of environmental pollutants are usually higher in mainland and coastal areas than in offshore or oceanic islands due to higher inputs from agricultural and industrial sources. Levels of heavy metals are usually higher in adult than in young birds, because they have had longer to accumulate metals in their tissues, and/or because they may eat larger, more contaminated, prey. We examined the levels of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in the adults and young of Bonin petrel (Pterodroma hypoleuca), Christmas shearwater (Puffinus nativitatis) and red-tailed tropicbird (Phaethon rubricauda) on Midway Atoll, and adult wedge-tailed shearwater (Puffinus pacificus) on Midway Atoll and on Manana Island (off Oahu) in the northern Pacific. All birds were analyzed individually except for Christmas Shearwater chicks where samples were pooled to obtain sufficient quantities for analysis. Significant (p<0.05) age-related differences were found for mercury, selenium, manganese and chromium in Bonin petrels, for selenium and mercury in Christmas shearwaters, and for chromium and mercury in Red-tailed Tropicbirds. Lead approached significance for all three species. Adults had higher levels than young except for chromium and manganese in the petrels and arsenic in all three species. There were significant interspecific differences in concentrations of all metals except arsenic for the adults nesting on Midway. Christmas shearwaters had the highest levels of all metals except mercury and chromium. Bonin petrels, the smallest species examined, had mercury levels that were over three times higher than any of the adults of the other three species. For wedge-tailed shearwaters, levels of chromium and lead were significantly higher, and manganese and selenium were lower on Midway than Manana. Knowledge of the foraging ranges and habits of these far-ranging seabirds is inadequately known, but does not currently explain the observed differences among species. We could not find a consistent pattern of differences between the burrow nesting species (Bonin petrel, Wedge-tailed shearwater) and the surface nesting tropicbirds. There was no consistent pairwise correlation between any metals across all species.  相似文献   
109.
Comparability of sediment analyses for semivolatile organic substances is still low. Neither screening of the sediments nor organic-carbon based normalization is sufficient to obtain comparable results. We are showing the interdependency of grain-size effects with inside-sediment organic-matter distribution for PAH, PCB and organochlorine compounds. Surface sediment samples collected by Van-Veen grab were sieved and analyzed for 16 PAH, 6 PCB and 18 organochlorine pesticides (OCP) as well as organic-matter content. Since bulk concentrations are influenced by grain-size effects themselves, we used a novel normalization method based on the sum of concentrations in the separate grain-size fractions of the sediments. By calculating relative normalized concentrations, it was possible to clearly show underlying mechanisms throughout a heterogeneous set of samples. Furthermore, we were able to show that, for comparability, screening at <125 μm is best suited and can be further improved by additional organic-carbon normalization.  相似文献   
110.
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