有机污染物在水体表面微层的富集行为

研究邻苯二甲酸二丁酯（ＤＢＰ）,邻苯二甲酸二异辛酯（ＤＥＨＰ）和阴离子表面活性剂在水体表面微层的富集行为．现场分析结果表明邻苯二甲酸酯在小型封闭湖泊表面微层中存在富集现象,富集倍数在１～１１之间,湖水的理化性质及采样方式均影响富集倍数的大小．室内微宇宙研究表明ＤＢＰ和ＤＥＨＰ在微宇宙水体表面微层中均存在富集现象,富集倍数分别为２．８１和１．９８,藻类、颗粒物和腐殖酸也同时在微宇宙水体表面微层中富集．当水体中加入表面活性物质和腐殖酸时,邻苯二甲酸酯（ＤＢＰ、ＤＥＨＰ）在表面微层的富集倍数随加入的２种物质浓度的增大而降低．对阴离子表面活性剂的富集动力学研究表明,当表面微层遭到破坏后,其在表面微层达富集平衡需较长时间,水体浓度也影响富集倍数     

Surface microlayer enrichment of volatile organic compounds and semi-volatile organic compounds in drinking water source

Enrichment of volatile organic compounds(VOC) and semi-volatility organic compounds(SVOC) in surface microlayer(SM) of three ddnking water sources were studied. The enrichment factor(EFs) were 0.67 to 13.37 and 0.16 to 136, respectively. The results showed some VOC and most SVOC could enrich in SM. Some EFs of SVOC was quite high. Suspension and temperature could affect EFs of SVOC, slim wind and water movement do not destroy enrichment of organic in SM.     

Occurrence and volatility of several trace elements in pulverized coal boiler

The contents of eight trace elements(Mn, Cr, Pb, As, Se, Zn, Cd, Hg) in raw coal, bottom ash and fly ash were measured in a 220 t/h pulverized coal boiler. Factors affecting distribution of trace elements were investigated, including fly ash diameter, furnace temperature, oxygen content and trace elements‘ characters. One coefficient of Meij was also improved to more directly show element enrichment in combustion products. These elements may be classified into three groups according to their distribution: Group 1. Hg, which is very volatile. Group 2: Pb, Zn, Cd, which are partially volatile. Group 3: Mn, which is hardly volatile. Se may be located between groups 1 and 2. Cr has properties of both group ! and 3. In addition, the smaller diameter of fly ash, the more relative enrichment of trace elements (except Mn). The fly ash showed different adsorption mechanisms of trace elements and the volatilization of trace elements rises with furnace temperature. Relative enrichments of trace elements(except Mn and Cr) in fly ash are larger than that in bottom ash. Low oxygen content can not always improve the volatilization of trace elements. Pb is easier to form chloride than Cd during coal combustion. Trace elements should be classified in accordance with factors.     

水培和盆栽条件下碎米莎草对铀的耐受性及富集特征

碎米莎草(Cyperus iria L.)作为铀的超耐受植物,它的发现为探讨铀污染环境的植物修复和铀在植物体中的吸收和耐受机理提供了一种新的资源. 在Hoagland's营养液中加入铀标准溶液模拟铀污染水环境,以及直接在铀尾沙条件分析不同铀供应水平下碎米莎草对铀的耐受性能和富集特征. 结果表明:①碎米莎草对铀的富集特征依赖于生长介质中铀的供应水平和植物生长期等多重因素. 碎米莎草不同生长期各部位w(U)均高于生长介质中的铀供应水平,根系和地上部分w(U)最高可分别达(48 605±1 266)和(824±856)mg/kg. 根、茎和叶中w(U)基本随着铀供应水平的升高而增加,在开花期时较低,根系吸收的铀有1/10~1/5能转移至茎、叶、花籽部位,ρ(U)<250 mg/L的铀溶液对碎米莎草的生长无抑制作用. ②碎米莎草对铀尾沙具有很强的耐受性,但地上部分的富集系数在某些条件下可大于1;地上部分的w(U)在开花期相对较高,至成熟期时下降;在成熟期添加柠檬酸有助于碎米莎草根、茎和叶将铀转移至籽部位.      

山阴水砷中毒区地下水砷的富集因素分析

通过对山阴地区66个地下水样中常量元素、微量元素及有机物分析,研究了山阴高砷地下水的水化学特性并在此基础上,结合该地区含水层沉积物矿物分析,探讨了地下水中砷富集的影响因素.结果表明,山阴地下水平均pH为8.09,磷酸根含量为0.71mg/L,溶解性有机物含量为5.14 mg/L,以及地下水处于还原环境.高pH值、高磷酸根含量及还原环境不利于含水介质对以阴离子形式存在的砷的吸附,高溶解性有机物含量则增加了砷的活性这些因素促使了含水介质中砷的解吸和迁移.     

Factors affecting the distribution of trace elements in harbour sediments

A large number of data (n=488) were acquired from 2003 to 2006 for five Italian harbours and three control areas to determine trace element (Al, As, Cd, Cu, Zn, Pb, Hg, Cr, and Ni) levels in sediments. Results were utilised to evaluate, on a multivariate statistical basis, pollution levels, significant relationships between observed levels and specific factors, and enrichment factors. Of the factors tested, main human use of harbour, was best able to determine segregations in the observed trace element fingerprints. Compared with the concentration limit approach, the evaluation of enrichment factors, even if affected by mathematical approximations, represented a useful tool for environmental studies, allowing evaluation of the presence of sediments enriched by human activities and reducing the occurrence of both false positives and false negatives due to natural differences in aluminosilicate levels.     

Sediment organic matter and meiofauna community response to long-term fish-farm impact in the Ligurian Sea (Western Mediterranean)

Quantitative and qualitative changes in meiofauna community structure were investigated to assess the impact of a fish farm, which was operating continuously for 15 years (La Spezia Gulf, W Mediterranean). Sediment samples were collected in June, July, September, October 2000 and February 2001 for the analysis of phytopigments (chlorophyll-a and phaeopigments), the biochemical composition of organic matter (proteins, carbohydrates and lipids) and related to meiofaunal parameters.

Sediment organic matter reached extremely high concentrations beneath the fish cages when compared to the control. Particularly lipids, carbohydrates and chlorophyll-a were significantly higher in fish-farm sediments. On a long-term basis meiofauna displayed adaptations in sediments beneath the cages resulting in an increase of density. Organic impact on meiofaunal community structure was evident in terms of an increase of the nematodes to copepods (Ne/Co) and nauplius to copepods (Na/Co) ratios in fish farm sediments. Cumaceans and kinorhynchs were encountered in control sediments, but disappeared in fish-farm samples. These data suggest that meiofauna is a sensitive tool for evaluating the effects of organic enrichment in fish farm impacted areas.     

甘肃省陇东塬区土壤及农作物中微量元素的分布特征

通过测定甘肃省陇东塬区马岭、西峰和华庆油田区土壤以及小麦、苹果、油菜中Cu、Ni、Cd、Pb、Cr、Zn等6种微量金属元素质量分数,研究塬区土壤中微量元素的空间分布特征及其在植物体内的转移、富集能力.结果表明:塬区土壤中w(Zn)明显高于其他5种元素,其平均值达111.64 mg/kg;w(Cd)最小,在1.64～3.38 mg/kg之间;其余4种元素(Cr、Pb、Ni、Cu)质量分数在20～70 mg/kg之间.当地主要农作物对土壤中微量元素的富集系数均小于1,富集能力一般,其中根部的富集能力相对较大,地上部位均较小.      

沈阳冬季灰霾日大气颗粒物元素粒径分布特征

为分析沈阳市冬季灰霾日大气颗粒物元素粒径分布特征,2009年1月14日─2月2日,用安德森分级撞击式采样器进行大气颗粒物分级采样,并用电感耦合等离子体质谱仪(ICP-MS)对各级样品中Na和K等30余种元素进行分析,讨论了灰霾日、非霾日及除夕日大气颗粒物元素质量浓度和富集因子的粒径分布特征及来源. 结果表明:灰霾日大气颗粒物及其元素的质量浓度均高于非霾日,粒径越细,质量浓度越高,越容易富集污染元素.Fe类元素以地壳元素为主,其质量浓度的粒径分布在非霾日呈双峰型,最高峰值出现在9.0～10 μm粗粒径段;该类元素的粒径分布在灰霾日和除夕日呈三峰型,质量浓度的最高峰值也在9.0～10 μm粗粒径段. Mn类元素在非霾日的质量浓度分布与Fe类元素相似,也呈双峰型,最高峰值出现在9.0～10 μm粗粒径段;但其在灰霾日和除夕日呈双峰型,最高峰值却出现在粒径<1.1 μm的细粒径段. K类和Zn类元素的质量浓度和富集因子的粒径分布均呈单峰型,峰值出现在粒径<1.1 μm的细粒径段. K类元素主要来源于烟花爆竹释放;Zn类元素主要源于人为污染,Pb和As等污染元素因其来源不同,在灰霾日和非霾日的表现也不相同.      

淮南市浅层地下水重金属元素的富集特征

以淮南市浅层地下水为研究对象,采集并测试了130个水样中Fe、Mn、Cu、Zn、Pb、Cd、Ni等元素的含量及相关指标。通过分析pH与重金属的相关性,得出了重金属在水中的富集速率,即VFe〉VCu〉VZn〉VPb〉VMn〉VNi〉VCd。利用主成分对7种重金属进行分类并分析其富集成因,最后将测试结果与土壤重金属含量相比较,确定了浅层地下水中的重金属元素的富集特征。