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1.
南宁城市内河水体和表层沉积物中多环芳烃分布特征   总被引:2,自引:2,他引:0  
采用改进的固相萃取、加速溶剂萃取和高效液相色谱对南宁7条城市内河的水体和表层沉积物样品中6种多环芳烃的残留状况进行了分析测定。检测结果表明,水体中多环芳烃以荧蒽为主,6种多环芳烃在水体中的总残留浓度为26.8~163 ng/L,内河水体各点位苯并[α]芘均超过我国地表水环境质量标准限值,对干流水质存在一定影响。7个点位沉积物中多环芳烃总含量为118.06~416.73μg/kg,6种多环芳烃均有检出。  相似文献   

2.
海洋沉积物基质多环芳烃(PAHs)标准参考物质是海洋环境沉积物监测分析中质量控制和质量保证的重要保障。由于缺少对相关原料样筛选研究,目前我国尚未有自主制备的海洋沉积物基质PAHs标准参考物质。通过海洋沉积物原始数据调研、定点筛查、实验室间验证等手段,对江苏近岸海域海洋沉积物原料样进行筛选研究。结果表明,连云港赣榆某入海口点位的海洋沉积物样品∑PAHs的质量分数为413μg/kg,该样品各粒径中的PAHs质量分数分布均匀,精密度能够满足我国海洋沉积物环境监测质量控制需求,可以为进一步制备海洋沉积物PAHs标准参考物质提供技术支持。  相似文献   

3.
建立了用微波萃取(MAE)、固相萃取(SPE)净化、气相色谱,串联四极杆质谱(GC-QqQ-MS/MS)多反应监测同时测定土壤中16种多环芳烃和18种邻苯二甲酸酯的方法.通过优化前处理与分析条件,样品加标浓度在5μg/kg时的平均回收率在66.59%~122.07%之间,相对标准偏差均小于20%,邻苯二甲酸酯的检出限在0.04.0.84.ttg/kg之间.定量限在0.13~2.81μg/kg之间;多环芳烃的检出限在0.01~0.54μg/ks之间,定量限在0.02~1.81μS/kg之间,能够满足大量样品快速准确分析的需要.  相似文献   

4.
为初步了解兰州市大气降尘中有机物的污染特征,采集了兰州市的大气降尘样品,分析了其中的16种多环芳烃和16种多氯联苯。结果表明,兰州市大气降尘中16种多环芳烃的总量为28.9 mg/kg,主要浓度组分为苊、苊烯、茚并[1,2,3-CD]芘和苯并[a]芘;16种多氯联苯的总量为172μg/kg,主要组分为PCB_(169)和PCB_(138)。生态风险评价的结果表明,兰州市22.2%的大气降尘样品多环芳烃总量处于低风险,66.7%的样品处于中等风险,多氯联苯总量以中等风险和高风险为主。  相似文献   

5.
焦炉工人PAHs空气日均暴露浓度分析   总被引:5,自引:0,他引:5  
用个体采样器对100名受试者进行了可吸入颗粒物和气态样品的24h跟踪采集,并通过梯度洗脱一反相HPLC/可编程序荧光检测法定量分析了样品中14种多环芳烃。结果表明,不同受试人员多环芳烃空气日均暴露浓度存在很大差异,其中焦炉工人受多环芳烃中BaP空气日均暴露浓度为0.5μg/m^3~1.7μg/m^3,炼纲厂工作人员和清洁区办公人员的BaP空气日均暴露浓度分别为0.02μg/m^3和0.01μg/m^3。不同受试人员多环芳烃空气日均暴露在PM10及气相中的分配比例也略有不同,焦炉工人的BaP空气日均暴露浓度有近99%来自PM10,一般人群为93%左右。指出2环、3环多环芳烃主要以气态形式存在,4环至6环多环芳烃主要分布在PM10中。  相似文献   

6.
利用高效液相色谱分析技术对福建省茶园土壤中16种多环芳烃进行了定量分析,结果表明,PAHs的总量在0.622~812.0μg/kg之间,平均值为48.4μg/kg。其组成以3环的为主,4环次之,主成分分析和PAHs特征参数分析发现,福建省茶园土壤中多环芳烃主要以燃油、木柴和煤燃烧来源为主,部分样点存在油类排放污染。生态风险评价结果显示,福建省茶园土壤中多环芳烃已具有不利生物影响效应。  相似文献   

7.
GC-MS/MS法测定石油污染土壤中的多环芳烃   总被引:1,自引:0,他引:1  
采用丙酮-正己烷混合溶液(体积比为1∶1)提取石油污染土壤样品中10种典型多环芳烃,用GC-MS/MS法测定。通过优化前处理和测定条件,使方法在0.100 mg/L~10.0 mg/L范围内线性良好,方法检出限为5.00μg/kg~15.8μg/kg。土壤样品加标回收试验6次测定结果的RSD为0.1%~16.6%,加标回收率为43.1%~109%。将该方法用于测定湖南某石化项目周边的实际土壤,结果表明该地区不同点位土壤中多环芳烃测定值为未检出~300μg/kg,在国家标准规定的范围内。  相似文献   

8.
加速溶剂提取气-质联用分析土壤中的多环芳烃   总被引:2,自引:2,他引:0  
建立了加速溶剂提取-凝胶渗透色谱净化和气相色谱-质谱联用快速分析土壤中16种多环芳烃的新方法。方法的检出限、定量限分别为1.1~12μg/kg、3.7~40μg/kg。16种PAHs的回收率为76.6%~96.8%,相对标准偏差为2.9%~9.5%。应用于多个环境样品的分析测试,结果满意。  相似文献   

9.
为了解莱芜市大气污染源排放颗粒物中多环芳烃的浓度及影响因素,采集机动车尾气尘、扬尘、工业燃煤颗粒物、民用燃煤颗粒物等4种样品,分别测定多环芳烃的含量。结果表明,莱芜市大气环境颗粒物中多环芳烃主要来源于机动车尾气和民用燃煤,12种多环芳烃类值分别为(1 536. 48±0. 78)和(299. 83±0. 30)μg/g,机动车尾气尘与扬尘、民用燃煤、工业燃煤多环芳烃均存在显著性差异。不同组分中,苯并(ghi)苝的值最高,为(559. 96±7. 59)μg/g,其次为晕苯,为(445. 36±5. 94)μg/g,城市空气污染呈现煤烟和机动车尾气复合污染的特点。  相似文献   

10.
用丙酮/正己烷(1∶1)混合溶剂,微波萃取法提取环境空气总悬浮颗粒物(TSP)中16种多环芳烃组分,各组分萃取率为66%~83%,萃取效果较好。高效液相色谱法二极管阵列检测器和荧光检测器串联可同时测出16种多环芳烃组分。在二极管阵列检测器响应的组分检测限为2 5μg/L~5 0μg/L,荧光检测器响应的组分检测限为0 01μg/L~0 1μg/L。对25μg/L16种多环芳烃标液作精密度试验,相对标准差均<5%,精密度好。取两个交通干线环境空气样品作TSP中多环芳烃测定,16种组分中除蒽、茚并(1,2,3cd)芘、芘、苊烯4种组分外,其他12种组分均有检出。  相似文献   

11.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

12.
微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬   总被引:25,自引:5,他引:25       下载免费PDF全文
用微波消解-原子吸收光度法测定土壤中铜,锌,铅,镉,镍和铬。通过硝酸-氢氟酸-过氧化氢体系消解液对土壤样品消解,选择出微波最佳消解条件。对硝酸-盐酸-过氧化氢体系消解液和硝酸-氢氟酸-过氧化氢体系消解液进行消解对比试验,发现前者不能将土壤样品完全消解,后者能将样品消解完全,但需将消解液中剩余的酸赶尽,否则测定结果将明显偏低。微波消解土壤与传统电热消解相比,操作简便快速,可提高工作效率。  相似文献   

13.
The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> -1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.  相似文献   

14.
The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) began in 1993 and is sponsored by 74 local, state, and federal agencies and companies through their discharge or Bay use permits. The RMP monitors water, sediment, toxicity, and bivalve bioaccumulation at 25 sites in the Bay that are considered to represent "background" conditions. Several major environmental issues have been identified by the RMP. Polychlorinated biphenyls and mercury were often above water quality guidelines, and often occurred in fish tissues above U.S. Environmental Protection Agency (U.S. EPA) screening values. Concentrations do not appear to be decreasing, suggesting continuing inputs. Episodes of aquatic toxicity often occurred following runoff events that transport contaminants into the Bay from urbanized and agricultural portions of the watershed. Sediment toxicity occurred throughout the Bay, and has been correlated with concentrations of specific contaminants (chlordanes, polynuclear aromatic hydrocarbons) at some locations; mixtures of contaminants were probably also important. Since the RMP does not monitor all ecosystem components, assessments of the overall condition of the Bay cannot be made. However, in terms of contamination, the RMP samples suggest that the South Bay, and North Bay sites are moderately contaminated.  相似文献   

15.
Citation of cyanobacterial cultures from the shores of south west coast of Gujarat, India and their relationship with sea water quality, influenced by extensive pollutant runoff is reported in this study. Intensity of pollution was evaluated by physico-chemical analysis of water. Higher load of suspended solids (60–1000 mg l−1) and nutrients (PO4 P: 1.3–4 μmole l−1 and NO3 N: 12.5–17.8 μmole l−1) were persistent throughout the analysis. Community structure is seen to be influenced by such persistent pollution. Twenty nine cyanobacterial species were isolated belonging to 9 genera of 4 families, with an elevated occurrence of Oscillatoria and Lyngbya species. No heterocystous cyanobacteria were isolated throughout the study.  相似文献   

16.
A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g-1 wet weight (ww), PCBs 0.69 g g-1, 2,3,7,8-TCDD 2.3 ng kg-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.  相似文献   

17.
Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.  相似文献   

18.
The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.  相似文献   

19.
The population counts of hydrocarbon-utilising yeasts weremonitored at six sampling stations in the Benin City municipalarea over a four-week period. Although the population countswere relatively constant in each locality, the highest countsoccurred in areas heavily polluted by domestic and industrialeffluents. A total of thirty-five hydrocarbon-degrading yeastswere isolated from soil at the sampling stations usingn-hexadecane as sole carbon source. The isolates were identifiedas belonging to the genera Candida (27 strains), Endomycopsis (4 strains). All the organisms grew on long-chainn-alkane, kerosene, diesel oil and crude oil but failed to growon short-chain n-alkane, aromatic and alicyclic hydrocarbons.Measurement of growth attributes of the isolates usingn-hexadecane, diesel oil and crude oil as substrates showed thatthe Candida species were better utilizers of hydrocarbonsubstrates relative to Endomycopsis and Schizosaccharomyces species.  相似文献   

20.
This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.  相似文献   

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