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1.
为方便地表水中总微囊藻毒素(TMCs)的预警监测,探究提取MC-LR、MC-RR、MC-YR的不同快速前处理方法,建立同时测定3种TMCs的煮沸-过滤-UPLC-MS/MS法。该方法在0.006μg/L~50.0μg/L范围内线性良好,方法检出限为0.006μg/L~0.010μg/L,实际水样3个质量浓度水平的加标回收率为88.6%~108%,6次测定结果的RSD为2.6%~9.4%。  相似文献   

2.
建立了针对地表水和地下水中11种三嗪类农药的超高效液相色谱三重四极杆质谱分析方法,并对前处理、仪器分析、方法特性指标等因素进行优化探讨。使用SB-C18色谱柱、乙腈水二元混合液流动相进行化合物分离,设置柱温为40℃、进样量为10μL,质谱采用正离子模式检测,内标法定量,采用平均相对响应因子法拟合标准曲线。结果表明,11种三嗪类农药的方法检出限为0.003~0.01μg/L,对3种质量浓度的基体加标样品分别进行6次平行分析,测定结果的相对标准偏差为2.1%~19%,平均加标回收率为80.0%~108%。采集地表水和地下水样品,经尼龙或聚四氟乙烯滤膜过滤后上机测定,在1种地表水样品中检出了阿特拉津和扑灭津,平均质量浓度分别为0.032和0.009μg/L。该方法具有准确度高、重复性好、检出限低等优点,能够满足现阶段地表水和地下水的环境管理监测要求。  相似文献   

3.
建立了超高效液相色谱-三重四级杆串联质谱(UPLC-MS/MS)快速测定地表水及饮用水中溴氰菊酯的方法,并应用于实际水样的检测分析。结果表明:水样经0.22μm滤膜过滤后可直接采用超高效液相色谱-三重四级杆串联质谱仪多重反应监测(MRM)模式定量检测水中溴氰菊酯;最优分析条件下,溴氰菊酯的检出限为0.30μg/L,其线性检测范围为0.30~20.0μg/L,相关系数为0.999 7;采用该方法检测水中的溴氰菊酯,不同水平(2.00、5.00μg/L和20.0μg/L)样品加标回收率为95.5%~98.5%,相对标准偏差为1.37%~3.59%。方法快速简便、灵敏度高、定性定量准确,适合日常批量水样的快速分析。  相似文献   

4.
对地表水样品中10种卤代烃测定方法进行优化,找出空白偏高的原因。方法优化后的加标回收率为90.1%~104%,相对标准偏差为1.1%~6.9%,检出限为0.000 3μg/L~2.0μg/L,可满足地表水环境质量分析要求。  相似文献   

5.
气相色谱法测定地表水中百菌清和菊酯类农药   总被引:1,自引:0,他引:1  
采用正己烷萃取地表水中的百菌清和6种菊酯类农药,通过毛细管气相色谱法-电子捕获检测器(GC-ECD)定性定量。供试农药的线性范围:百菌清为10.0μg/L~200μg/L,6种菊酯类为50.0μg/L~1 000μg/L;方法检出限分别为:百菌清0.054μg/L,甲氰菊酯0.62μg/L,三氟氯氰菊酯0.68μg/L,氯菊酯0.40μg/L,氯氰菊酯0.65μg/L,氰戊菊酯0.78μg/L,溴氰菊酯0.15μg/L;对地表水样品3个质量浓度水平的平均加标回收率为91.3%~118%,6次平行测定的RSD<5%。  相似文献   

6.
UPLC-串联质谱法快速测定地表水中多种农药残留   总被引:1,自引:0,他引:1  
采用超高效液相色谱-串联质谱法测定地表水中21种氨基甲酸酯和有机磷农药,通过优化试验条件,使方法在0. 500μg/L~100μg/L范围内线性良好,方法检出限为0. 1μg/L~6. 2μg/L。对空白水样做3个质量浓度水平的加标回收试验,5次测定结果的RSD为0. 3%~9. 5%,回收率为82. 0%~113%。将该方法用于测定徐州某地表水样品,3个水样均为未检出。  相似文献   

7.
地表水中SVOCs和氨基甲酸酯类农药同步萃取技术的探讨   总被引:1,自引:0,他引:1  
采用大体积固相萃取富集地表水中SVOCs和氨基甲酸酯类农药,再以气相色谱-质谱和超高效液相色谱-串联质谱联用对目标物定性定量。通过优化固相萃取条件,使SVOCs在0.500 mg/L~10.0 mg/L之间,氨基甲酸酯类农药在1.00μg/L~100μg/L之间线性良好,方法检出限为0.002μg/L~0.009μg/L,加标回收率分别为70.5%~105%和78.5%~124%。用该方法测定某流域地表水,结果邻苯二甲酸酯类物质、多环芳烃类、酚类、硝基苯环类化合物等SVOCs,以及克百威、仲丁威等氨基甲酸酯类农药检出。  相似文献   

8.
饮用水源水样品经过直接进样或固相微萃取法净化后,用超高效液相色谱/串联质谱测定水中11种藻毒素。通过试验优化测定条件,使该方法在0.500μg/L~50.0μg/L范围内线性良好,检出限为0.01μg/L~0.05μg/L。对同一实际环境样品做3个质量浓度水平加标回收试验,6次测定结果的RSD为2.2%~9.3%,回收率为76.1%~108%。将该方法用于测定环巢湖湖面12个监测断面水样,结果 3组样品中MC-YR、MC-LR和MC-RR值为0.3μg/L~0.8μg/L。  相似文献   

9.
采用微球硅胶键合C_(18)固相萃取柱萃取水样中的3-甲基吲哚,并用气质联用法测定,方法在0 mg/L~10.0 mg/L范围内线性良好,方法检出限为0.2μg/L。空白水样3个质量浓度水平的加标回收率为89%~94%,7次测定结果的RSD为2.3%~6.9%。用该方法测定7个实际地表水样品,其中4个地表水样品检出3-甲基吲哚,地表水样的加标回收率为81.5%~97.0%。  相似文献   

10.
本文建立了用便携式气相色谱-质谱仪快速测定土壤中VOCs的方法。该方法能够快速对土壤样品中VOCs进行定性分析和定量测定。当采样量达到5 g时,方法检出限0.02~2.11μg/L,相对标准偏差2.0%~13.5%;加标20μg/L时,回收率63%~123%。采用该方法测定北京地区5个土壤样品,总体质量浓度为0~873μg/kg。  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:24,自引:5,他引:24       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.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   

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