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1.
建立了一种液-液小体积萃取GC-MS快速测定地表水中氯苯类化合物的分析方法。该方法具有操作简单快速、适用性广和试剂用量很少等特点。当萃取试剂用量为2ml时(约为一般常规液-液萃取用量的数十分之一),萃取富集效率可达300~500倍,回收率为93%~98%,相对标准偏差为4%~8%,检出限为0.1~0.3μg/L。  相似文献   

2.
针对地表水特定项目有机物中硝基苯类和氯苯类的测定,采用固相微萃取(SPME)前处理技术,用毛细管色谱柱进行色谱分离,用ECD检测器进行测定。SPME富集效率达118~1352倍,检出限为0.00004~0.05μg/L,方法的线性相关系数为0.9963~0.9999,RSD为2.0%~11.0%,加标回收率为87.0%~108%,所有技术参数均可满足地表水环境质量标准。该方法简单、快捷、无污染且省时省力,具有较好的推广性。  相似文献   

3.
顶空气相色谱法测定地表水中的氯苯   总被引:1,自引:0,他引:1  
采用液上顶空气相色谱法 ,以毛细管柱分离 ,FID检测 ,测定地表水中的氯苯。方法检测限 2 μg/L ,加标回收率 83 %~ 113 % ,相对标准差 4 5 %~ 6 0 % ,精密度和准确度均较好  相似文献   

4.
文章研究并建立了一种快速便捷测定水中硝基氯苯类化合物的方法。采用固相微萃取方法富集水中目标物,使用便携式气相色谱/质谱仪进行检测。优化后的萃取条件为:使用65μm的PDMS/DVB萃取头,水温60℃、转速200r/min下萃取50min。结果表明,硝基氯苯类化合物在10.0~500μg/L范围内呈现良好线性,相关系数均大于0.980;空白水样加标相对标准偏差为2.28%~11.3%,加标回收率为77%~130%;实际水样加标相对标准偏差为3.93%~6.73%,加标回收率为90%~115%;检出限范围为1.37~3.57μg/L。  相似文献   

5.
通过将动态吹扫捕集气相色谱-质谱联用技术在线化,实现了全自动在线测定地表水中的54种挥发性有机物(VOCs),并能对其他VOCs进行定性半定量监测。54种VOCs的方法检出限为0.05~0.74μg/L,在0~10μg/L范围内线性良好;加标回收率为69.6%~107.2%;除1,2,4-三氯苯等5种VOCs外,其余49种VOCs的测定标准偏差均10%。该方法检出限、线性、准确度和精密度都能满足水质自动监测的需要。  相似文献   

6.
针对碱性过硫酸钾消解紫外分光光度法测定含泥沙的地表水中总氮时,数据准确度常受到絮凝沉淀的干扰的问题,采用一次性0.45μm水相针式滤器过滤消解后水样,快速有效地去除絮凝沉淀的干扰,达到了提高含泥沙的地表水总氮测定准确度的目的。结果表明,该方法相对标准偏差2.0%,加标回收率为92.0%~96.5%,符合实验室质控要求。  相似文献   

7.
采用直接进样法,通过超高效液相色谱串联质谱法对水体中19种磺胺类抗生素进行了测定,并对仪器条件进行优化。结果表明,该方法测定19种磺胺类抗生素的线性良好,相关系数均≥0.996,检出限为0.1~0.5μg/L。对鱼塘地表水、医院废水和药厂废水这3种不同基质的水样进行加标回收实验,回收率为84.0%~119%,相对标准偏差为0.3%~10.2%。该方法简单、快速、准确度和精密度较高、溶剂消耗较少,可在25 min内快速测定19种磺胺类抗生素,能够满足水体中磺胺类抗生素的快速检测要求。  相似文献   

8.
建立了一种吹扫捕集-气相色谱/质谱法同时测定水中的乙醛、丙烯醛、丙烯腈、吡啶、松节油和丁基黄原酸的分析方法。结果表明,吹扫时间、脱附时间、脱附温度和盐酸用量是影响目标化合物测定的关键因素,对吹扫捕集条件优化后,各目标化合物线性良好,相关系数均0.998,检出限为0.13~2.22μg/L,加标回收率为80.5%~111%,相对标准偏差为1.1%~10.9%,能够满足地表水环境质量标准的要求。  相似文献   

9.
建立了一种采用吹扫捕集气质联用法同时测定水中氯乙烯、乙醛、丙烯醛、丙烯腈、吡啶和松节油的分析方法,研究并优化了吹扫捕集前处理条件参数。结果表明,吹扫时间、吹扫温度和脱附时间是影响目标物的吹扫捕集效率的关键因素;优化后方法线性良好,相关系数均大于0.999,检出限范围为0.20~1.48μg/L,加标回收率范围为86.9%~105%,相对标准偏差为1.1%~9.8%。建立的吹扫捕集GC-MS联用法简便、快速、灵敏度高、定性定量准确可靠,可同时满足对自来水、地表水、地下水等水样中痕量氯乙烯、乙醛、丙烯醛、丙烯腈、吡啶和松节油监测的要求。  相似文献   

10.
采用吹扫捕集-气相色谱/质谱联用法测定地表水中氯丁二烯。当进样体积为20 mL时,方法在0.100μg/L~50.0μg/L范围内线性良好,检出限为0.05μg/L,标准溶液平行测定的RSD≤3.7%,地表水样加标回收率为91.0%~101%,方法可用于地表水中卤代烃、苯系物等其他21种挥发性有机物的同时测定。  相似文献   

11.
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   

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 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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
用火焰原子吸收光谱法测定了苏州开发区26种蔬菜中的铜、锌、铁、锰和镍的含量。蔬菜样品用硝酸高氯酸混合酸进行消解。4次测定值的相对标准差<5%,加标回收率在92%~107%之间。26种蔬菜中铜、锌、铁、锰、镍的含量基本均在世贸组织规定的范围内。  相似文献   

19.
Using Multiple Taxonomic Groups to Index the Ecological Condition of Lakes   总被引:6,自引:0,他引:6  
Biological indicators of communitiestypically reflect a common environmental signalreflecting the general condition of the ecosystem, as well asindividual signals by indicators differentiallysensitive to particular environmental conditions. Wedescribe here a method of integrating and interpretingsuch indicators from 19 New England lakes for fivetaxonomic groups (diatoms, benthos, zooplankton, fish,and birds). Our approach provides a systematicstandardized way to integrate multiple metrics fromdifferent taxonomic groups by addressing four elementscrucial to analyzing data from multiple indicators: covariate control, re-scaling of data, standardizing the sign of responses, and dimensional reduction. We evaluated the biologicalmetrics against individual environmental stressors andagainst multivariate physicochemical metricscharacterizing general anthropogenic stress among thelakes. The method detected a response to variationin the gross environmental condition of the lakes thatwas correlated across taxa and metrics. In addition,a differential response to near shore conditions wasdemonstrated for fish. The success of the approach inthis study lends support to its general application toecological monitoring involving complex data sets.  相似文献   

20.
We determined concentrations of selected trace elements inlivers, kidneys and blood samples from common eiders (Somateria mollissima borealis) from the eastern Canadianarctic during 1997 and 1998. Concentrations of totalmercury and organic mercury were generally low in the liversof these birds (less than 6 and 4 g g–1 dry wt,respectively). Selenium ranged between 11–47 g g–1 inlivers. Renal cadmium concentrations were among the highestever published for this species (range: 47–281 g g–1). The regressions of log-transformed concentrations ofthese trace elements in blood samples on those in liver orkidney were significant (all P-values < 0.05) andpositive. However, except for organic mercury (RM 2 = 0.83), the co-efficients of determination were low tomoderate (range of R 2: 0.26–0.52), suggesting poorto moderate predictive capability. Furthermore, therelationships between total mercury in blood and liverchanged between 1997 and 1998, suggesting that it would notbe possible to predict consistently, concentrations ofmercury in blood from those in liver based on samples takenin one year. Blood samples can be used to determineconcentrations of these trace elements in common eiders (andprobably other sea duck species as well). The use of bloodsamples is especially warranted when it is undesirable tokill the animal such as when working with rare or endangeredsea duck species or when the objective is to relate traceelement exposure to annual survival rates. However, thepredictive equations developed here should not be used topredict expected concentrations in one type of tissue fromthose in the other.  相似文献   

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