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1.
采用KOH梯度淋洗离子色谱法测定地表水和饮用水中ClO2-、BrO3-和ClO3-,在试验确定的条件下,3种离子与F-、Cl-、NO2-、NO3-、SO2-4、Br-、I-等7种离子分离度良好。 ClO2-、BrO3-、ClO3-在50.0μg/L~1000μg/L范围内线性良好,检出限分别为5.2μg/L、8.9μg/L、7.6μg/L,环境水样加标平行测定的RSD分别为2.1%~5.4%、4.1%~5.4%、2.5%~4.8%,两个质量浓度水平加标的平均回收率分别为93.7%~96.5%、90.3%~94.8%、98.7%~111%。  相似文献   

2.
液液萃取-气质联用法测定饮用水源地水中SVOCs   总被引:3,自引:0,他引:3  
采用乙酸乙酯-正己烷混合溶剂(体积比为2∶1)对饮用水源地水中阿特拉津、林丹、邻苯二甲酸二正丁酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)和滴滴涕(含4种)等8种半挥发性有机物进行1次水样萃取,用气质联用法同时测定。试验表明,方法在25.0μg/L~500μg/L范围内线性良好;检出限在0.006μg/L ~0.028μg/L 之间;空白水样3个质量浓度水平的加标回收率为87.6%~109%,平行测定6次的 RSD<5.1%;测定集中式生活饮用水源地的实际水样,未检出目标化合物,加标回收率为98.6%~109%。  相似文献   

3.
采用新型金膜吸附-冷原子吸收光谱法测定空气中的汞,在0μg/L~100μg/L范围内线性良好,相关系数为0.9991。方法检出限为1.6 ng/m3,RSD为0.5%~2.7%,测定两种不同浓度的汞标准样品,相对误差为6.1%和3.2%。与两种现行国标方法(巯基棉富集和高锰酸钾溶液吸附法)比较,该方法所需试剂种类少,操作简便、吸附效率好,加标回收率高。  相似文献   

4.
采用微波消解-原子荧光光谱法测定大气细颗粒物中的砷,确定了最佳样品处理方法与测定条件。方法在0μg/L~40.0μg/L范围内线性良好,标准曲线相关系数达0.999以上,检出限为0.01μg/L。土壤标准品的测定值在标准值范围内,大气PM2.5滤膜样品加标回收率为96.0%~102%,5次平行测定的RSD为1.5%~3.6%。  相似文献   

5.
采用二氯甲烷提取地表水,浓缩后经超高效液相色谱紫外-三重四级杆质谱检测器联用测定甲萘威。试验表明:紫外检测器测定甲萘威,在2.00μg/L~500μg/L范围内线性良好,相关系数为0.9992,检出限为0.500μg/L;三重四级杆质谱检测器测定甲萘威,在0.100μg/L~200μg/L范围内线性良好,相关系数为0.9990,检出限为0.009μg/L;实际水样3个浓度水平的加标回收率为92.4%~98.4%,RSD为2.5%~6.5%。该方法中双检测器联用测定地表水加标样品,使得定性定量更加准确。  相似文献   

6.
采用便携式GC-MS测定水体中的苯胺,并对水样中离子强度和顶空分析的平衡时间进行优化。试验表明,苯胺在10.0μg/L~200μg/L范围内有较好的线性,r为0.998;方法检出限为5.8μg/L;回收率为92.8%~96.7%;RSD为3.2%~8.6%。用54种VOCs混合标样对苯胺标液进行干扰试验,结果试验条件下苯胺与VOCs得到有效分离。  相似文献   

7.
建立了毛细管低温吸附气相色谱同时测定空气中痕量甲硫醇和硫化氢的方法,介绍了冷冻吸附装置的制备方法和样品冷凝吸附流程。甲硫醇和硫化氢分别在0.467ng~5.16ng和0.327ng~3.60ng范围内线性良好,当进样体积为1L时,检出限为0.205μg/m^3和0.213μg/m^3,空白加标平均回收率为88.6%和90.2%,RSD为6.0%和6.5%。  相似文献   

8.
磁性分散固相萃取-气相色谱法测定水中氯苯类化合物   总被引:1,自引:0,他引:1  
采用磁性分散固相萃取技术富集水中氯苯类化合物,用气相色谱法测定,并对萃取剂的用量、萃取时间、解吸溶剂、氯化钠加入量等条件进行优化。试验表明,方法在0.001 mg/L~2.50 mg/L 范围内,氯苯类化合物各组分线性良好,方法检出限在0.600μg/L~5.00μg/L范围内。地表水实际水样的加标回收率为83.1%~93.4%,RSD为4.8%~7.3%。  相似文献   

9.
采用二氯甲烷萃取水样,气相色谱-串联质谱法同时测定水中有机磷农药和甲萘威。试验表明:方法在20.0μg/L ~1000μg/L范围内,各目标化合物线性良好;方法检出限为0.004μg/L~0.01μg/L;对实际水样进行3个质量浓度水平的加标回收试验,回收率在71.8%~94.5%之间,RSD为3.7%~8.5%,满足水中痕量有机磷农药和甲萘威的测定要求。  相似文献   

10.
王荟  章勇  李娟 《干旱环境监测》2009,23(3):141-144
在采用双柱双检测器的基础上,对水中24种挥发性有机物进行了同时测定。当进样体积为5ml时,最低检测限为0.5俐L,线性范围及测定范围为0.5~50倒L,1μg/L和20μg/L浓度水平的加标回收率在80.0%-110%之间,变异系数为0.6%~9.2%,实验结果令人满意。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
Impact of Pollution Caused by Uranium Production on Soil Macrofauna   总被引:1,自引:0,他引:1  
Thirty years of mining and milling activities of the Priargunsky Mining-Chemical Production Company (South-Eastern Siberia, Russia) have resulted in an enrichment of uranium in adjacent steppe soils by a factor of up to 600. A number of attendant pollutants (thorium, arsenic and heavy metals) also have high concentrations in the soil. To estimate the effects of this pollution on soil-living macroinvertebrates, pitfall trapping and core sampling were applied. The element composition of four beetle species was analysed. Soil macroinvertebrates had 3–37 times lower abundance and biodiversity at the contaminated sites compared with the control. Ground beetle communities at the contaminated sites were reduced compared to the control site. The concentrations of uranium and arsenic in beetles collected at the contaminated sites were 2–41 and 2–26 times higher, respectively, than at the control site. There is strong evidence that the contamination caused by uranium production has severe negative biological effects on important groups of the soil food web.  相似文献   

20.
Water requirements to supply human needs lead water stakeholders to store more water during surplus periods to fulfil the demand during – not only – scarcity periods. At the reservoirs, mostly those in semi-arid regions, water level then fluctuates extremely between rises and downward during one single year. Besides of water management implications, changes on physical, chemical and biological dynamics of these drawdown and refilling are little known yet. This paper shows the results, throughout a year, on solids, nutrients (N and P), chlorophyll-a, and sedimentation changes on the dynamics, when the former policy was applied in a reservoir from the semi-arid Northwestern Mexico. Water level sinusoidal trend impinged changes on thermal stratification and mixing, modifying nutrient cycling and primary producer responses. According to nitrogen and phosphorus concentration as well as chlorophyll-a, reservoir was mesotrophic, becoming hypertrophic during drawdown. Nutrient concentrations were high (1.22 ± 0.70 and 0.14 ± 0.12 mg P l−1), increasing phosphorus and lowering N:P significantly throughout the study period, although no intensive agricultural, no urban development, neither industrial activities take place in the watershed. This suggests nutrient recycling complex mechanisms, including nutrient release from the sediment–water interface as the main nutrient pathway when shallowness, at the same time as mineralization, increases. Outflows controlled nitrogen and phosphorus availability on the ecosystem while organic matter depended on river inflows. As on other subtropical aquatic ecosystems, nitrogen limited primary productivity (Spearman correlation R = 0.75) but chlorophyll-a seasonal pattern showed an irregular trend, prompting other no-nutrient related limitants. Shallowness induced a homogeneous temporal pattern on water quality. This observed temporal variability was mainly explained statistically by changes on solids (mineral and organic), chlorophyll-a and flows (62.3%). Annual sedimentation rates of total solids ranged from 11.73 to 16.29 kg m−2 year−1 with organic matter comprising around 30%. N:P ratio on sedimentation rates were as high as could be expected in a resuspension dominated ecosystem, and spatially inverse related with N:P ratio on bottom sediments. Distance from river inlet into the reservoir reveals a marked spatial heterogeneity on solid and nitrogen sedimentation, showing the system dependence on river inflows and supporting resuspension as the main phosphorus pathway. Accretion rates (2.19 ± 0.40 cm year−1) were not related to hydrological variability but decreased with the distance to the river input. Total sediment accumulation (9,895 tons km−2 year−1) denotes siltation as other serious environmental problem in reservoirs but possibly not related with operational procedures.  相似文献   

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