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电子废物拆解区农业土壤中PCNs的污染水平、分布特征与来源解析 总被引:1,自引:1,他引:0
用GC-NCI-MS法测定了路桥农业表层土壤中46种多氯萘(PCNs)的含量.目的是了解该地区表层土壤中PCNs的污染水平、空间分布特征和来源.结果表明,所有表层土壤样品中ΣPCNs的含量为0.062~2.92 ng.g-1,平均值为0.630 ng.g-1.多数样品中tetra-CNs和penta-CNs是最主要的同族体,分别占18.4%~88.8%(平均值为46.7%)和8.40%~53.1%(平均值为30.7%),其次是tri-CNs,范围为0~47.3%,平均值为10.6%.聚类分析和燃烧指示物分析表明,采样点主要受Halowax1014和Halowax 1013工业品污染,PCBs工业品和电子废物燃烧也可能对污染有贡献.与国内外其它研究相比,研究区域内土壤中PCNs污染处于中等水平. 相似文献
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中国东北主要河流沉积物中多溴二苯醚的含量状况及生态风险分析 总被引:1,自引:1,他引:0
为揭示多溴二苯醚(PBDEs)在东北主要河流流域内的污染现状,通过采集该地区流域内表层沉积物样品,采用GC-NCIMS技术对沉积物中41种PBDEs同类物进行分析.结果发现沉积物中BDE209含量低于检出限,其它40种PBDEs同类物总含量(不包含BDE209)范围(干重)为0.91~17.67 ng·g-1.其中第二松花江吉林市上游和下游沉积物样品中PBDEs的检出含量最高,分别为15.86 ng·g-1、17.67 ng·g-1,以BDE207和BDE47为主,分别占PBDEs总量的86.5%和76.6%;其它河流沉积物中各同族体含量差异并不明显.实验结果与国内外最近的文献报道值相比较,再结合生态风险分析显示,东北主要河流沉积物中PBDEs的含量处于低污染水平,目前不存在生态风险. 相似文献
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有机氯农药在海河菹草根际和非根际沉积物中的分布特征 总被引:1,自引:0,他引:1
于2008年3~5月对海河干流沉水植物菹草根际和非根际沉积物中有机氯农药(OCPs)的分布进行了采样调查.结果表明,菹草根际沉积物中六六六(HCHs)、滴滴涕(DDTs)的含量分别为6.95~31.55ng·g-1(均值16.43ng·g-1,下同)和13.99~42.57ng·g-1(23·77ng·g-1),非根际沉积物中HCHs、DDTs的含量分别为1.80~8.09ng·g-1(4.66ng·g-1)和3.27~26.51ng·g-1(14.81ng·g-1);;除1个数据点外,菹草根际沉积物中OCPs含量均比非根际沉积物有明显的增加;;菹草根际沉积物中β-HCH、p,p′-DDE分别是HCHs和DDTs的主要组成成分,而非根际沉积物中β-HCH和p,p′-DDE和p,p′-DDD是主要成分. 相似文献
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《中国环境科学》2017,(2)
采用气相色谱-三重四极杆质谱联用技术对苏南地区34个表层土壤中的多氯萘(PCNs)进行了分析测定,并对其组成特征及污染来源进行了研究.结果表明,苏南地区土壤中SPCNs的浓度水平在0.263~2.48ng/g dw之间,除16号采样点PCNs浓度(2.48ng/g dw)显著偏高外,其余各点平均值为0.464ng/g dw,毒性当量(TEQs)的变化范围在0.045~0.157pg/g dw之间,整体处于较低水平.所有样品中PCNs均以一氯代萘和二氯代萘为主,所占比例为39.3%~91.4%.CN-66/67、CN-69和CN-73对该区域PCNs的TEQs值贡献最大,分别为25.6%,29.1%和28.7%.SPCN_(Com)/∑PCNs比值表明,高温燃烧过程对整个苏南地区PCNs的污染影响较大.相关性分析与主成分分析研究表明,老电气设备的使用及交通排放过程也是造成该区域PCNs污染的可能来源.但该地区PCNs污染来源较复杂,各点位PCNs的来源需深入研究. 相似文献
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珠江口水、沉积物及水生动物中氯苯类有机物的含量及分布 总被引:13,自引:0,他引:13
对珠江口水、沉积物及水生动物体内氯苯类有机物(CBs)的污染现状进行了调查,并对该类污染物在水体多介质体系中的转移分配规律进行了初步研究1.结果表明,珠江口表层水中CBs的总浓度为16.44~963.20ng·L-,DCBs(二氯苯)对污染的贡献较为突出,占74.4%;表层沉积物(干重)中CBs总含量为7.83~40.09 ng·g-1,DCBs、TCBs(三氯苯)、TeCBs(四氯苯)、PeCB(五氯苯)和HCB(六氯苯)分别占总量的71.4%、11.1%、13.0%、1.2%、3.6%;水生动物中贝类的CBs平均含量是38873.0ng·g-1、鱼类为2360.3ng·g-1、虾类则为565.0ng·g-1,DCBs和TeCBs是水生动物体内的主要污染物.CBs在水、沉积物及生物体之间存在明显的富集和放大作用. 相似文献
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截污调水后滇池表层沉积物中16种PAHs的分布特征 总被引:4,自引:3,他引:1
截污调水等工程实施后,滇池的外源污染已得到有效控制,表层沉积物等内源污染物应加以重视.为研究滇池表层沉积物中16种多环芳烃(PAHs)的分布特征,采用气相色谱-质谱联用法(GC-MS)分析了2016年12月采集的19个滇池表层沉积物样品的PAHs含量,解析其时空分布规律、来源及生态风险.滇池表层沉积物中总多环芳烃(TPAHs)的含量范围为92. 31~1 546. 78 ng·g~(-1),平均值为496. 30 ng·g~(-1),草海TPAHs含量(平均932. 37 ng·g~(-1))远高于外海(平均380. 02ng·g~(-1)),随着截污调水工程的开展,TPAHs含量较2012年大幅下降,已处于我国重点水域中较低水平.滇池表层沉积物中含量最高的物质为荧蒽(80. 65 ng·g~(-1)),毒性当量(TEQ)含量最高的物质为二苯并[a,h]蒽(42. 97 ng·g~(-1)). PAHs组成以4环及5~6环为主(分别占总含量的40. 38%和40. 22%),PAHs构成较以往大体一致.分子比值法分析结果表明,滇池表层沉积物中PAHs主要由生物质或煤的燃烧贡献.基于潜在生态风险标志对比法评估,全湖总体处于低风险水平,但草海的生态风险相对较高,值得进一步关注.本研究结果可为滇池水质的保持与提升提供基础数据和重要参考. 相似文献
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多环芳烃(Polycyclic aromatic hydrocarbons,PAHs)具有“三致”效应,其在环境中的污染特征及行为倍受关注.长江作为我国经济发展的重要纽带,其PAHs污染特征及来源亟需明晰.本研究以长江干流(攀枝花至南京)及主要支流为研究区域,分析了表层沉积物中19种PAHs的污染特征和来源,评估了PAHs类污染物的生态风险.结果表明,长江上游、中下游及主要支流江段沉积物中Σ19PAHs浓度分别为55.2~406.4ng·g-1(均值(216.3±139.2) ng·g-1)、48.0~500.4 ng·g-1(均值(337.1±197.0) ng·g-1)、90.1~429.8 ng·g-1(均值(268.0±129.0) ng·g-1).其中4环、5~6环类PAHs浓度范围分别占38.9%和39.9%.以三峡大坝为界,上游越靠近大坝沉积物中PAHs浓度越高,中下游越靠近长江口沉积物中PAHs浓度越高;近20年来长江干流沉积物中PAHs浓... 相似文献
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This work was conducted to evaluate whether Ca-bearing additives used during coal combustion can also help with the retention of some other elements. This work was focused on the evaluation of bottom ashes collected during four full-scale combustion tests at an operating thermal fluidized-bed power station. Bottom ashes were preferred to fly ashes for the study to avoid interference from condensation processes usually occurring in the post-combustion zone. This work focused on the behaviors of S, Cl, Br, As, Mn, V, Cr, Ni, Cu,Zn, W, and Pb. Strong positive correlations with CaO content in bottom ashes were observed(for all four combustion tests) for S, As, Cl and Br(R = 0.917-0.999). Strong inverse proportionality was calculated between the contents of Pb, Zn, Ni, Cr and Mn and CaO, so these elements showed association to materials other than Ca-bearing compounds(e.g., to aluminosilicates, organic matter, etc.). Somewhat unclear behaviors were observed for W, Cu, and V. Their correlation coefficients were evaluated as statistically "not significant", i.e., these elements were not thought to be significantly associated with CaO. It was also discovered that major enrichment of CaO in the finest bottom ash fractions could be advantageously used for simple separation of elements strongly associated with these fractions, mainly S and As, but also Cl or Br. Removal of5% of the finest ash particles brings about a decrease in As concentration down to 77%-80% of its original bulk ash content, which can be conveniently used e.g., when high As content complicates further ash utilization. 相似文献
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Paul Ney 《Die Naturwissenschaften》1981,68(12):597-605
Types of asbestos are distinguished not only by structure, chemical compositon, shape of aggregates, and length and quality of fibers, but also by its formation. Though consisting of quite common elements, deposits are formed only under very special conditions. Its unique combination of properties has created over 3000 fields of application (about 70% in asbestos cement). Great efforts have been made to substitute all types of asbestos by harmless, similarly cheap and versatile synthetic fibers, owing to the unquestioned carcinogenic properties of all asbestos dusts. However, development of such fibers has not made any remarkable progress until recently. Consequently risk to workers in mining and manufactoring, consumers, outsiders, and the environment should be kept as low as possible by intensifying precautions and diminishing emissions. 相似文献
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珊瑚钨锡矿硅质尾矿中Cd、As、Zn、F富集迁移及环境污染 总被引:1,自引:0,他引:1
硅质尾矿在释放中性矿山废水(NMD)时所伴生的多元素复合污染问题值得重视。本文以桂东北珊瑚矿尾矿作为研究对象,通过分析该尾矿的组构、元素富集及迁移特性,筛选出主要污染元素,并探讨尾矿胶结层对元素富集迁移的影响。结果表明:(1)该尾矿中Cd、As、Zn及F富集程度较高、可交换态含量(易迁移释放量)较大,是主要的污染元素,而Cu、Pb、Tl产生污染的可能性较小;(2)胶结层对重金属具有再富集作用,但其对可交换态Cd、As(Tl)再富集明显,而对可交换态Cu、Pb、Zn再富集则不明显。胶结层中次生伊利石、石膏等胶结物趋向于吸附富集活性可交换态Cd、As。这表明该尾矿可能迁移释放出含Cd、As浓度较高的NMD。研究表明,硅质尾矿风化释出NMD的同时,可能伴生Cd、As、Zn等重金属以及F的复合污染。 相似文献
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Vine Edward L. Sathaye Jayant A. 《Mitigation and Adaptation Strategies for Global Change》2000,5(2):189-216
In this paper, we present an overview of guidelinesdeveloped for the monitoring, evaluation, reporting,verification, and certification (MERVC) ofenergy-efficiency projects for climate changemitigation. The monitoring and evaluation ofenergy-efficiency projects is needed to determine moreaccurately their impact on greenhouse gas (GHG)emissions and other attributes, and to ensure that theglobal climate is protected and that countryobligations are met. Reporting, verification andcertification will be needed for addressing therequirements of the Kyoto Protocol. While the cost ofmonitoring and evaluation of energy-efficiencyprojects is expected to be about 5–10% of a project'sbudget, the actual cost of monitoring and evaluationwill vary depending on many factors, including thelevel of precision required for measuring energy andGHG reductions, type of project, and amount of fundingavailable. 相似文献
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Kurunthachalam Kannan Simonetta Corsoline Takashi Imagaws Silvano Focardi John P.Giesy 《Ambio-人类环境杂志》2002,31(3):207-211
我们曾对从意大利收集的金枪鱼、箭鱼、普通鸬鹚以及家燕体内的p,p'-DDE、多氯联苯同类物(PCBs)、多氯二苯-p-二恶英(PCDDs)、多氯二苯并呋喃(PCDFs)以及多氯萘(PCNs)浓度进行过测量. 相似文献
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共沉淀-离心-X射线荧光法快速测定表层海水中的Fe,Ni,Mn,Cu,Zn,Pb 总被引:1,自引:0,他引:1
基于共沉淀的富集作用,采用自制的离心管离心沉淀,以手持式X-射线荧光仪(XRF)测定,由此建立了表层海水中Fe,Ni,Mn,Cu,Zn,Pb的共沉淀-离心-XRF快速分析方法。测定时间为5 min/样;线性范围125μg/L~1 000μg/L,可以满足近岸表层海水中铁和锰的分析要求;基底加标200μg/L回收率为94.5%~116%;连续7次测定6种金属浓度均为500μg/L的海水加标样品,相对标准偏差(RSD)为2.86%~5.85%。与ICP-MS法比较,测定结果无显著性差异。本方法具有化学试剂污染小、方便快捷、可现场快速测定方法等优点。该方法已成功应用于厦门西港和福建九龙江河口表层海水中可溶态铁锰的现场测定,并在现场以手持式XRF对颗粒物中铁锰进行了测定,获得了该海域颗粒物中和海水中铁锰的分布。 相似文献