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1.
2006年4月在武汉月湖采集了8个样点的水样和表层沉积物样品,采用气-质联用技术分析了样品中25种半挥发性有机污染物(SVOCs)的含量,探讨月湖受有机物污染的程度.水样中25种半挥发性有机污染物总浓度为564.04-1209.41ng/L,平均值为965.64ng/L.沉积物中总浓度为8500.26-23347.20ng/g(DW),平均值为14832.04ng/g(DW).邻苯二甲酸酯类物质是月湖的主要污染物,其中,邻苯二甲酸乙基己基酯和邻苯二甲酸二丁酯含量最高.多环芳烃、硝基甲苯、异佛尔酮等均有不同程度检出,靠近以前的排污口的样点浓度最高.沉积物中25种半挥发性有机污染物的含量大约是水体中含量的15倍,具有潜在生态风险. 相似文献
2.
为研究广州市湖泊水体中的防腐剂及其毒性,在广州市选择15个湖泊采集水样,采用液液萃取-气质联用法对湖泊水体中的对羟基苯甲酸甲酯、对羟基苯甲酸乙酯等5种防腐剂进行浓度检测和毒性分析.结果表明:广州市区内15个湖泊水体中均检出防腐剂,但其浓度略低于国外天然水体中的浓度,溶解相的防腐剂平均浓度为5.06 ng/L,颗粒相的平均浓度为0.78 ng/L;广州市区的湖泊水体中溶解相浓度最高的防腐剂为对羟基苯甲酸丁酯,占总量的30.45%,对羟基苯甲酸苯甲酯所占比例最小,占6.71%;以防腐剂对发光细菌光强的抑制强弱来表征其毒性的大小,对羟基苯甲酸苯甲酯的毒性最强,对广州市湖泊水体环境的影响最大. 相似文献
3.
应用物种敏感性分布评价中国湖泊水体中重金属污染的生态风险 总被引：7，自引：2，他引：5
为总体了解我国主要湖泊水体重金属污染现状与生态风险,本文通过历史数据收集,利用物种敏感性分布(SSD)模型与主成分分析法,分析了我国18个湖泊或水域中6种重金属(Zn、Cd、Cr、Cu、Hg和Pb)的分布情况以及其对湖泊淡水生物的潜在生态风险(PAF)和联合生态风险(ms PAF).结果表明:在18湖泊中,6种重金属在湖泊水体中的浓度由高至低依次为Zn(均值为17.06μg/L,范围为4.03~29.33μg/L)、Pb(均值为9.33μg/L,范围为0.04~33.7μg/L)、Cr(均值为5.56μg/L,范围为0.65~40.0μg/L)、Cu(均值为3.71μg/L,范围为0.02~10.2μg/L)、Cd(均值为1.17μg/L,范围为0.01~13.6μg/L)和Hg(均值为0.19μg/L,范围为0.03~1.04μg/L);18个湖泊中重金属的分布情况由3个主成分反映,F1(Cu、Zn、Hg)、F2(Pb、Cd)和F3(Cr、Cu)的贡献率分别为28.50%、24.17%和18.40%,其分布情况受经济和地域差异影响较小;SSD模型显示,不同重金属对全部淡水生物的HC5值不同,从小到大依次为CuCrHgCdPbZn,淡水生物对重金属Cu的敏感性最高,对重金属Zn的敏感性最低;将选取的18个湖泊按ms PAF排序,由高到低依次为呼伦湖(67.0%)鲁湖(56.7%)洱海(52.7%)金银湖(52.3%)太湖(40.5%)墨水湖(39.3%)滆湖(30.2%)鄱阳湖(26.8%)洪泽湖(23.1%)高宝卲伯湖(22.4%)巢湖(20.7%)乌梁素海(19.7%)东湖(19.1%)梁子湖(4.0%)汤逊湖(2.0%)洞庭湖(1%)洪湖(0)=骆马湖(0).研究结果对于了解我国淡水湖泊水质现状和环境安全风险具有重要意义,为湖泊的进一步保护与管理提供了一定的科学依据. 相似文献
4.
我国现行淡水水体中磷测定方法为钼酸铵分光光度法（GB 118931989）,该方法检测下限为0.01 mg/L,但我国南亚热带地区部分水体的总磷以及多数水体的溶解态磷浓度均低于0.01 mg/L,通过对标准试样和野外水样的测定,分析该方法在监测低磷浓度水体中可能出现的问题并提出改进方法.结果表明：对于磷浓度低于0.01 mg/L的水体,国标法灵敏度低,准确性差.通过3个方面的改进可提高该方法测定的灵敏度和准确性：1）将消解水样体积由25 ml增加到50 ml,消解后不再进行二次稀释定容;2）改变显色剂的配制,显色剂由14%硫酸溶液50 ml、酒石酸锑钾溶液5 ml、4%钼酸铵溶液15 ml和0.1 mol/L的抗坏血酸溶液30 ml混合而成,现配现用;3）将测定波长设置为880 nm.改进后方法的灵敏度有较大提高,能准确、有效地检测磷浓度在0.003~0.01 mg/L的水样. 相似文献
5.
2008年至2020年期间,对三峡水库小江5个监测断面的叶绿素a(Chl.a)及主要环境因子进行季度监测,分析小江Chl.a的时空变化特征,探讨水体Chl.a与环境因子的相关关系,解析影响小江Chl.a变化的主要环境因子。结果表明,小江Chl.a年平均浓度为(20.69±9.41)μg/L,变幅为5.96～33.90μg/L。Chl.a浓度季节差异较大,总体呈现出春、夏、秋3个季节明显高于冬季的变化特征,且春季Chl.a浓度最高,为34.48μg/L;空间分布上,Chl.a浓度呈现倒“N”型分布规律,黄石断面最高(29.55μg/L),养鹿断面最低(15.23μg/L)。Pearson相关性分析结果显示,小江Chl.a浓度与CODMn、电导率、pH、溶解氧呈显著正相关关系,与NO3--N、PO43--P、透明度呈显著负相关关系。通过逐步回归分析,筛选得到对小江Chl.a影响最重要的5个环境因子。通径分析表明,各环境因子对水体Chl.a浓度的作用大小在时空上存在一定差异。不同季节... 相似文献
6.
目的:研究256层螺旋CT机头颈部血管成像(CTA)检查对原发性蛛网膜下腔出血(SAH)患者的诊断作用以及血清S-100B蛋白检测对SAH患者脑损害程度及脑血管痉挛的评价作用。方法:选取2013年4月至2014年3月期间我院收治的SAH患者共77例,根据格拉斯哥昏迷(GCS)评分和Hunt-Hess分级分成不同组别,对其进行256层螺旋CT机头部CTA检查及血清S-100B蛋白水平的检测。结果:在77例SAH患者中,经CT机头部CTA检查共有59处动脉瘤。GCS评分3~8分患者入院后1天、7天S-100B蛋白水平分别为(1.94±0.31)μg/L、(1.93±0.28)μg/L明显高于GCS评分9~12分患者入院后1天、7天S-100B蛋白水平(1.13±0.21)μg/L,(1.09±0.19)μg/L和GCS评分13~15分患者入院后1天、7天S-100B蛋白水平(0.54±0.09)μg/L,(0.52±0.06)μg/L,差异具有统计学意义(P<0.05)。Hunt-HessⅠⅡ级患者入院后1天、7天S-100B蛋白水平分别为(0.68±0.12)μg/L和(0.64±0.11)μg/L明显低于Hunt-HessⅢ级患者入院后1天、7天S-100B蛋白水平(1.15±0.18)μg/L,(0.98±0.12)μg/L和Hunt-HessⅣ级患者入院后1天、7天S-100B蛋白水平(2.08±0.25)μg/L,(1.99±0.23)μg/L,差异具有统计学意义(P<0.05)。结论:256层螺旋CT机头颈部CTA检查可对SAH患者周边血管三维结构予以有效反应,对SAH患者行S-100B蛋白水平检测,能有效对SAH患者脑损害程度及血管痉挛做出评价。 相似文献
7.
珠江流域东江干流浮游植物叶绿素a时空分布及与环境因子的关系 总被引：7，自引：2，他引：5
为了解珠江流域东江干流水体叶绿素a的时空分布及与环境因子的关系,于2012年6月(丰水期)和12月(枯水期)对东江干流进行采样调查分析.结果表明,东江水体叶绿素a含量具有明显的时空分布特征,其全年变化范围为0.84~14.93μg/L,整体均值为3.60±2.45μg/L,丰水期叶绿素a含量显著高于枯水期;而丰、枯水期叶绿素a含量空间分布特征相似,上游河段显著低于下游河段.相关性与主成分分析结果显示,水体中总氮浓度、总磷浓度、有机物含量、水温和水流流速等都是影响东江浮游植物生长的重要因素,其中以总磷的影响最为显著,表明磷可能是东江浮游植物生长的限制因子. 相似文献
8.
秋季聚积蓝藻打捞对蓝藻生长及水质影响的原位实验 总被引：1，自引：0，他引：1
在巢湖西北半湖近岸设置3组小型围隔模拟秋季湖岸带蓝藻聚积,并用单片鳃式过滤器原位打捞蓝藻,研究秋季打捞对蓝藻生长的影响及其对营养盐、藻源性有机物的控制效应.初始围隔水体叶绿素a浓度为309.5±3.7μg/L,总氮和总磷浓度分别为3.32±0.14和0.30±0.04 mg/L.蓝藻衰亡分解释放的藻源性有机物为水体溶解性有机物的主要来源,荧光有机物以类蛋白物质为主.经过打捞,浮游植物生物量削减了41.7%,解除了蓝藻生长"密度制约",24 h细胞分裂频率及原位生长速率均增大,说明打捞在短期内增强蓝藻细胞生长活力,减缓藻源性有机物的释放.与秋季蓝藻衰亡趋势一致,实验周期内围隔中叶绿素a浓度逐渐降低,秋季打捞不会造成蓝藻水华再次暴发.打捞通过削减蓝藻生物量,使水体初级生产力、氮、磷、高锰酸盐指数得到显著控制;而且打捞还可以控制藻源性有机物的释放,使藻源性大分子有机物更易降解为小分子有机物.因此,在秋季对湖岸带聚积蓝藻进行物理打捞,不仅可以控制蓝藻生物量,还可以有效控制营养盐和有机物的释放,降低生态风险. 相似文献
9.
云南省重点湖库水体透明度和叶绿素a建议控制指标的探讨 总被引：10，自引：0，他引：10
为了控制云南省高原湖泊的富营养化,切实改善湖库的水环境质量,本文在通过调查统计云南省辖区内的典型湖库和国内外相关指标分析评价研究的基础上,提出了云南省重点保护湖库水中透明度、叶绿素a环境控制指标的标准限值:Ⅰ类5．0m、Ⅱ类2．5m、Ⅲ类为1．0m、Ⅳ类和Ⅴ类均为0．5m;叶绿素a为:Ⅰ类2μg／L、Ⅱ类10μg/L、Ⅲ类20μg/L、Ⅳ类40μg／L、Ⅴ类60μg／L.这两项控制指标能与国家标准有较好的衔接,可作为云南省执行GB3838-2002《地面水环境质量标准》时重点湖库的地方补充标准限值． 相似文献
10.
五种天然水体胶体相可酶解磷的含量及分布特征 总被引：3，自引：1，他引：2
分别在太湖草型湖区胥口湾及藻型湖区梅梁湾采集水样,采用常规过滤与切向流超滤相结合的方法,将水体中的颗粒,胶体依据粒径大小分离,通过测定计算得到64-1μm,1-0.5μm,0.5-0.1μm,0.1μm-1nm,<1nm五个粒级的可酶解磷含量.同时采集太湖"引江济太"工程长江调水口--望虞河口水样、千岛湖水样及千岛湖下游河流型水库富春江段水样进行分析.结果显示,5种典型水体中颗粒相的可酶解磷含量占总可酶解磷含量的比重较高,胶体相的可酶解磷也占了相当的比重,是生物必需磷不可忽视的重要储库.望虞河口河水总磷0.216mg/L,可酶解磷含量达0.174mg/L,其输入可能对太湖水体生物有效磷浓度的增加起到重要的贡献,"引江济太"调水时具有一定生态风险.对于胶体范围的可酶解磷,胥口湾、望虞河的胶体态可酶解磷主要分布在较大、中胶体范围,梅梁湾和千岛湖的胶体态可酶解磷主要分布在中、微胶体范围,富春江水库的胶体态可酶解磷分布的相对比较均匀. 相似文献
11.
Formation of Artefacts and its Suppression during the Determination of Volatile Halogenated Hydrocarbons in Water by Means of Headspace Gas Chromatography under the Standard Conditions of DIN 38407-F5. Part II: Increased Trihalomethane Formation in Chlorinated Swimming-pool Water A comparison of two analytical standard procedures for the determination of trihalomethanes (THM) in water (headspace gas chromatography and pentane extraction/gas chromatography) yielded strongly differing results. Under the conditions recommended by the German Standard Method DIN 38407-F5 (60…80°C for at least 60 min) degradation of thermo-labile chlorination products occurs resulting in elevated THM concentrations. The reactions involved are partly pH-dependant, and these can be suppressed by sample acidification. The degradation of trihalogen acetic acids, however, can only be influenced by minimizing the equilibration time and temperature. Other intermediate chlorination products (haloacetonitriles) are also degraded to THM after preceding hydrolysis to the corresponding carboxylic acids. Comparative results obtained with a purge and trap method at ambient temperature, i.e. without thermal stress during the enrichtment step, are lower than with static headspace GC but still high in comparison to the pentane extraction method. Presumably volatile THM-precursors are also trapped and subsequently decomposed upon thermal desorption from the trap. As the static headspace GC is the most rational method of LHKW determination available, the recommended experimental sample handling conditions should be modified in a way that deterioration reactions are reduced as far as possible. 相似文献
12.
Samples of water, sediment and mussels (Mytilus edulis) from the southern Baltic Sea have been analysed for total hydrocarbons by fluorescence spectroscopy and capillary gas chromatography. The sediment and mussel samples have also been analysed for specific aliphatic and aromatic hydrocarbons by computerized capillary gas chromatography-mass spectrometry. The highest hydrocarbon concentrations in all samples occurred either inshore (particularly in Gdansk Bay) or in deep offshore basins where fine sediment accumulates. 相似文献
13.
Artefact-free Determination of Trihalomethanes in Chlorinated Swimming-pool Water Using Headspace Solid-phase Microextraction and Gas Chromatography Headspace solid-phase microextraction (headspace SPME) is a rather new technique for the solvent-free extraction and concentration of volatile substances from water into an organic polymer layer covering a fused-silica fiber. In combination with gas chromatography, the method represents a powerful tool for sensitive headspace investigations. As the adsorption of low boiling substances is favoured at low temperatures, the method can be operated at ambient temperature without formation of artefacts. Therefore, the method is ideally suited for the analysis of volatile disinfection by-products in water including several thermolabile THM-precursors. For the artefact-free determination of trihalomethanes it is superior to headspace gas chromatography under the conditions of the German standard method DIN 38407-F5. Compared to gas chromatography after pentane extraction (DIN 38407-F4), headspace SPME is simpler, less- laborious, better reproducible, and, especially for polar, easily water-soluble components, much more sensitive. In addition, it operates solvent-free and can be automated. Using a 100-μ polydimethylsiloxane-coated fiber, the method is linear over at least 2 orders of magnitude and has a relative standard deviation of 2… 7% in the upper ng/L range. With a 65-μ polydimethylsiloxane/divinylbenzene-coating on the fiber, the sensitivity of the method can be extended to limits of quantitation in the low ng/L range. However, this fiber, shows an increased susceptibility to matrix effects as observed in the presence of diisopentyl ether, which can only be compensated by using the method of standard addition. 相似文献
14.
D.M Jones A.G Douglas R.J Parkes J Taylor W Giger C Schaffner 《Marine pollution bulletin》1983,14(3):103-108
Aromatic hydrocarbon fractions isolated from sediments polluted with crude oil, from sampling stations in and around Sullom Voe, Shetland Islands, were found to exhibit, as the major feature in their gas chromatograms, an unresolved complex mixture or ‘hump’. This feature was absent from the gas chromatograms of the aromatic hydrocarbon fractions isolated from corresponding unpolluted sediments in the region. The observed aromatic hump had little resemblance to the distribution of aromatic hydrocarbons in a typical North Sea crude oil. Incubation studies, however, showed that such a hump was appearing when oil-spiked sediments were aerobically biodegraded. From these incubation studies it was also evident that alkylaromatic hydrocarbons in the crude oil were biodegraded before any change in the normal alkanes was apparent. Therefore, the presence of an unresolved complex mixture in the gas chromatograms of aromatic hydrocarbon fractions from recent sediments can act as a marker to recognize contamination by crude oil. 相似文献
15.
巢湖蓝藻死亡衰败过程中典型有害成分形成及控制对策 总被引：6，自引：4，他引：2
蓝藻暴发及其打捞后的随意堆放,会产生藻毒素、多环芳烃、臭味气体等有毒物质.通过实验室模拟巢湖蓝藻死亡衰败过程,检测其中的有机元素、沥青(A)、饱和烃、芳烃等含量变化,探讨了死亡衰败阶段蓝藻有害成分尤其是多环芳烃等有毒物质的形成及控制对策.结果表明,蓝藻死亡衰败过程中,经兼性工艺处理的蓝藻其芳烃类总含量最低,多环芳烃的种类和含量也最低.单纯厌氧作用使芳烃含量略有升高,而单纯的好氧作用使饱和烃含量增高,并随作用时间的延长而增加,在好氧处理3个月的蓝藻中达到最高值.因此,本文认为兼性工艺处理的蓝藻最适于堆肥等资源化利用,其发酵液通入农田用作肥料,气体收集用于燃烧.并且提出依靠蓝藻死亡衰败过程中的藻胆蛋白、叶绿素等的荧光强度来监测其死亡衰败进程,进而控制其有害成分形成的对策. 相似文献
16.
This paper evaluates the concentration of Polyaromatic hydrocarbons - PAHs in the Estuarine area of the Patos Lagoon, more precisely in a local named "Saco do Laranjal" in Pelotas City (southern Brazil). The samples were collected in May 2008. The concentrations of 16 US-EPA priority polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography with a mass spectrometry detector (GC/MS). The sum of PAHs concentration ranged from 7.3 to 92.8μgkg(-1) in dry weight. The positive correlation (Pearson test) between the total organic material (TOM) and the total PAH concentration (0.98) suggests that TOM plays an important role in controlling the PAHs levels in the sediments. According to the observed ratios of individual PAHs, the contamination in the studied area is originated, predominantly pyrolytic sources. The values found are considered under normal levels and indicates a not impacted area. 相似文献
17.
G Gassmann 《Marine pollution bulletin》1981,12(3):78-84
In aliphatic hydrocarbon fractions of crude oils eight acyclic isoprenoid alkanes were separated from accompanying n-alkanes and iso-alkanes by high-performance glasscapillary gas chromatography. Four of these: 2,6,10-trimethyltetradecane (V), norpristane (IV), pristane (III), and phytane (II) could be resolved further to reveal a doublet produced by the different diastereoisomers.In these doublets the front peak represents stereoisomers formed during maturation of crude oil while the rear peak indicates the respective hydrocarbons carrying the original biogenic precursor configuration. This appearance of doublets demonstrates the loss of stereospecificity in hydrocarbons derived from phytol (I). By using the front peaks as diagenetic ‘maturity markers’ attributable to fossil fuels, hydrocarbon mixtures extracted from sea water samples contaminated with fossil oil could be investigated in detail. The quantitative relationship between recent biogenic and fossil fuel hydrocarbons could be determined in extracts in the lower boiling point range. 相似文献
18.
《Acta Geochimica》2013,(3)
Samples around a coal gangue dump of the Gequan Coal Mine were collected in April 2009. GC (gas chromatography) and GC/MS (gas chromatography/mass spectrometry) were employed to analyze the composition of organic matter in the samples. ICP-MS (inductively coupled plasma mass spectrometry) was used to determine the concentrations of heavy metals. The contents of organic extracts are within the range of 140-750 mg/kg. Alkand aro-ratios are relatively high. Compared to those of the background sample (GQ13 ), the contents of saturated hydrocarbon compounds in all the samples are relatively high. The contents of polycyclic aromatic hydrocarbons (PAHs) are relatively high with the distance getting closer to the coal gangue dump. These indicate that organic matter in the samples is from coal particles of the coal gangue dump. The distributions of heavy metals are very similar: the contents decrease with distance from the dump, which indicates that the harmful heavy metals from the coal gangue dump have polluted as thick as at least 500 m. 相似文献
19.
Investigation of natural and anthropogenic hydrocarbon inputs in sediments using geochemical markers. I. Santos, SP--Brazil 总被引：2，自引：0，他引：2
A study on the inputs of organic matter to marine sediments of Santos Bay and Estuary, located in southeastern S?o Paulo State, Brazil, is presented here. The following geochemical markers were identified and quantified: aliphatic hydrocarbons (normal and isoprenoid alkanes), petroleum biomarkers, linear alkylbenzenes (LABs) and polycyclic aromatic hydrocarbons (PAHs). Sediment samples, collected at 15 sites in the bay and surrounding channels, were extracted and analyzed by gas chromatography with flame ionization and mass spectrometer detectors. Total concentrations varied from 0.17 to 107.80 microg g(-1) for aliphatics, from 47.2 to 2560.1 ng g(-1) for petroleum biomarkers, from 16.9 to 430.6 ng g(-1) for LABs and from 79.6 to 15389.1 ng g(-1) for PAHs. Anthropogenic contributions were apparent, indicating the influences of the Cubatao industrial complex, sewage outfalls along the area, the waste deposit of Santos city and storage facilities for petroleum and derivatives, based on the higher concentrations of geochemical markers detected. 相似文献
20.
The water-soluble fractions of unleaded gasoline, kerosene and diesel fuel were evaluated by U.S. EPA Methods 602, 610, and 625.
Several chemical indicator compounds useful in assessing petroleum contamination of ground water, including benzene, substituted benzenes, n-alkanes, and polynuclear aromatic hydrocarbons, were identified. These were applied to the interpretation of data collected from monitoring wells at gasoline service stations that were undergoing ground water remediation. The chemical indicators are used to identify the likely type(s) of petroleum contamination. Certain hydrocarbons may be unique to specific fuel types.
Gas chromatograms of field sample extracts were compared with chromatograms of laboratory water-soluble fractions (WSFs) and neat fuels (unleaded gasoline, kerosene, and diesel). In some situations, field samples represented water-soluble fractions of the contaminating fuel. In others, a fuel-water agglomeration was indicated, with the chromatograms showing peaks that represented components of both the WSFs and the neat fuels.
The use of both gas chromatography pattern identification and chemical indicators appears to be a viable approach to assessing ground water contamination caused by petroleum products. 相似文献
Several chemical indicator compounds useful in assessing petroleum contamination of ground water, including benzene, substituted benzenes, n-alkanes, and polynuclear aromatic hydrocarbons, were identified. These were applied to the interpretation of data collected from monitoring wells at gasoline service stations that were undergoing ground water remediation. The chemical indicators are used to identify the likely type(s) of petroleum contamination. Certain hydrocarbons may be unique to specific fuel types.
Gas chromatograms of field sample extracts were compared with chromatograms of laboratory water-soluble fractions (WSFs) and neat fuels (unleaded gasoline, kerosene, and diesel). In some situations, field samples represented water-soluble fractions of the contaminating fuel. In others, a fuel-water agglomeration was indicated, with the chromatograms showing peaks that represented components of both the WSFs and the neat fuels.
The use of both gas chromatography pattern identification and chemical indicators appears to be a viable approach to assessing ground water contamination caused by petroleum products. 相似文献