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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   

2.
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   

3.
采用程序控温石墨全自动消解仪消解土壤样品,原子荧光光谱法测定总砷。通过试验确定原子荧光光度计的最佳工作条件,使得该方法在2.00μg/L ~20.0μg/L 范围内线性良好,检出限为0.025 mg/kg,加标回收率在96.0%~10^5%之间,RSD为1.9%~3.3%。用该方法与国标法同时测定土壤标准样品和实际样品,结果无显著差异。  相似文献   

4.
采用快速溶剂萃取-固相萃取-液相色谱串联质谱法(LC-MS/MS)测定土壤中8种多溴联苯醚类(PBDEs)化合物,通过优化试验条件,使方法在100 μg/L~1 000 μg/L范围内线性良好,方法检出限为085 μg/kg~125 μg/kg。不同土壤样品的8种多溴联苯醚回收率为68.6%~127%,4次测定结果的RSD为4.8%~27.6%。将该方法用于测定电子废物拆解点周边的土壤样品,结果BDE-209测定值为未检出~168 μg/kg,BDE-183为未检出~560 μg/kg,其余6种BDEs均为未检出。  相似文献   

5.
电感耦合等离子体质谱法测定饮用水中15种稀土元素   总被引:1,自引:0,他引:1  
采用电感耦合等离子体质谱法测定饮用水中15种稀土元素,采取内标校正法,以Rh、Re、Bi为内标,结合优化仪器条件和干扰校正方程来消除干扰.15种稀土元素的方法检出限为0.000 2μg/L~ 0.003 μg/L,混合标准溶液平行测定的RSD< 6%,饮用水样品的加标回收率为98%~120%.  相似文献   

6.
沉积物样品用乙腈-柠檬酸缓冲溶液提取后经HLB-SPE柱净化,采用LC-MS/MS法在MRM模式下测定17种磺胺类和4种四环素类抗生素,通过优化测定条件,使方法在0. 500μg/kg~100μg/kg范围内线性良好。方法检出限为0. 15μg/kg~1. 2μg/kg,2个质量比水平的加标回收率为44. 1%~125%,试验5次结果的RSD 16. 0%。将该方法用于测定厦门近岸海域沉积物中抗生素,共有6种磺胺类和4种四环素类抗生素检出,测定值为0. 3μg/kg~26. 2μg/kg。  相似文献   

7.
以二氯甲烷-丙酮(体积比1∶1)为混合溶剂,用加速溶剂萃取仪萃取土壤样品中的阿特拉津,提取液通过凝胶渗透色谱净化,用高效液相色谱仪在220 nm波长下测定,试验表明,在0.05 mg/L~5.00 mg/L范围内线性良好。方法检出限为0.22μg/kg,对空白土壤进行加标回收,平行测定6次,平均回收率为88.2%~102%,RSD为4.5%~7.6%,符合农药残留分析的要求。  相似文献   

8.
采用二氯甲烷萃取稻田水样品,土壤样品用丙酮-二氯甲烷(体积比为9∶1)混合溶液提取,二氯甲烷萃取,水稻植株样品用乙腈-二氯甲烷(体积比为9∶1)混合溶液直接萃取,用气相色谱法同时测定样品中稻瘟酰胺和咪鲜胺残留。该方法在0.012 2 mg/L~2.68 mg/L范围内线性良好,稻田土壤、田水、水稻植株中稻瘟酰胺的检出限分别为2.75μg/kg、1.83μg/L、3.80μg/kg,咪鲜胺的检出限分别为3.55μg/kg、2.66μg/L、5.62μg/kg。空白稻田土壤、稻田水和水稻植株样品3个浓度水平的加标回收率为80.3%~104%,RSD为3.0%~13.2%。  相似文献   

9.
采用微波消解处理鱼肉样品,用电感耦合等离子体质谱法测定样品中砷和汞。通过试验优化微波消解参数、酸体系及赶酸温度,用在线加入内标方法消除基体干扰及仪器漂移对测定的影响。方法在0μg/L~40. 0μg/L范围内线性良好,砷和汞的方法检出限分别为0. 002 mg/kg和0. 001 mg/kg,实际样品6次测定结果的RSD为5. 4%~15. 6%,加标回收率为90. 0%~110%。将该方法用于测定芹菜和扇贝标准物质,测定值在标准值不确定度范围内。  相似文献   

10.
氢化物发生-原子荧光光谱法测定土壤中镉   总被引:1,自引:0,他引:1       下载免费PDF全文
采用氢化物发生-原子荧光光谱法测定土壤中的镉,优化了试验条件,讨论了共存元素的干扰及消除办法。方法在0μg/L~120μg/L范围内线性良好,检出限为0.003 mg/kg(按取样0.600 g定容至45 mL计),土壤标准样品测定的RSD≤3.7%,加标回收率为94.8%,与石墨炉原子吸收分光光度法的测定结果相吻合。  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.
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   

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.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

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