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1.
浊点萃取分离富集荧光光度法测定水中α - 萘酚   总被引:2,自引:1,他引:1       下载免费PDF全文
基于非离子表面活性剂Triton X-114,采用浊点萃取分离富集荧光光度法测定水中α-萘酚,优化了影响浊点萃取的各种因素,包括样品酸度、表面活性剂体积分数、氢氧化钠溶液浓度、平衡温度和时间等,讨论了常见无机离子和可能共存的有机物的干扰。方法在0.010 mg/L~0.400 mg/L范围内线性良好,检出限为3.0μg/L,标准溶液测定的RSD为4.8%,水样加标回收率为94.3%~103%。  相似文献   

2.
采用固相萃取-GC-MS/MS法测定水中10种N-亚硝胺类化合物,通过试验优化前处理和测定条件,使方法在0. 500μg/L~100μg/L范围内线性良好。方法检出限为0. 6 ng/L~2. 1 ng/L,混合标准溶液6次测定结果的RSD 5%。将该方法用于测定实际水样,结果除N-亚硝基二甲胺、N-亚硝基甲基乙基胺和N-亚硝基二丙胺以外,其余目标物均为未检出,加标回收率为73. 1%~97. 6%。  相似文献   

3.
通过固相萃取法提取地表水中10种氨基甲酸酯类农药,萃取溶液经浓硫酸脱色,佛罗里硅土柱除杂,用柱后衍生高效液相色谱法测定.在5μg/L~500μg/L范围内,标准曲线线性关系良好,仪器检出限低于1μg/L,水样平均加标回收率为90.0%~101%,RSD为1.1%~9.2%.  相似文献   

4.
采用基质分散固相萃取-同位素稀释-HPLC-MS/MS法同时测定三角帆蚌肉中9种N-亚硝胺类化合物(NAs),通过优化前处理和仪器条件,使方法在5.00μg/L~200μg/L范围内线性良好,方法检出限为2.58μg/kg~8.86μg/kg。对样品做2个质量比水平的加标回收试验,各组分的平均回收率为78.1%~90.3%,RSD值≤6.8%。将该方法用于测定20个河蚌样品,9种NAs均为未检出。  相似文献   

5.
采用氢氧化铁共沉淀载带水中钍,经浓硝酸溶解沉淀后,采用三辛烷基叔胺(N-235)混匀溶液萃取,盐酸反萃取,进一步纯化分离钍,与铀试剂Ⅲ形成络合物后用分光光度法测定。方法在0. 05 mg/L~0. 500 mg/L范围内线性良好,方法检出限为0. 025μg/L,探测下限为0. 10μg/L。将该方法用于实际水样的测定,6次测定结果的RSD为7. 0%~19. 6%,回收率为90. 0%~92. 4%。  相似文献   

6.
采用液液萃取-气相色谱法测定饮用水中10种硝基苯类化合物,通过萃取条件优化试验,选择正己烷为萃取剂,使目标物在0μg/L~38.5μg/L之间线性良好,检出限为0.002μg/L ~0.005μg/L。实际饮用水样的加标回收率为80.8%~104%,RSD<3%。用该方法测定桂林市4个水厂饮用水,结果硝基苯、间-二硝基苯、2,4-二硝基氯苯未检出,其余7种硝基苯类化合物虽有检出,但检出值均低于标准规定的限值。  相似文献   

7.
采用液液萃取/固相萃取净化/气相色谱法测定废水中9种硝基苯类化合物,通过萃取条件优化试验,选择乙酸乙酯:正己烷=(2:1)为萃取剂,佛罗里硅土柱为净化小柱,目标物在0~1000μg/L之间线性良好,检出限为0.0085~0.156μg/L。实际水样的加标回收率为71%~92%。用该方法测定4批废水,结果其中有硝基苯类化合物虽有检出,但检出值均低于相关标准规定的限值。  相似文献   

8.
利用100μmPDMS(聚二甲基硅氧烷)涂层,建立了非平衡固相微萃取_气相色谱_质谱联用测定水中甲拌磷的新方法。在萃取效果确证的基础上,对溶液体积、萃取时间、搅拌速度和溶液离子强度等实验条件进行了优化。方法的线性范围为0 005~50μg/L,相关系数为0 997,检测限(信噪比3∶1)为0 002μg/L,对于0 1μg/L的甲拌磷相对标准偏差(n=6)为7 16%。所建立的方法直接用于田间表面水和河水样品中甲拌磷的测定,结果满意。  相似文献   

9.
用Waters Oasis MCX固相萃取小柱富集水中的苯胺和联苯胺,以2%氨水-甲醇混合溶液为洗脱液,采用高效液相色谱法DAD检测器在285 nm波长下测定。苯胺和联苯胺分别在0 mg/L~100 mg/L和0 mg/L~10.0 mg/L范围内线性良好,检出限分别为0.3 μg/L和0.1 μg/L,饮用水加标平行测定6次的RSD分别为0.9%和0.3%,回收率分别为98.3%~99.1%和97.6%~102%。  相似文献   

10.
水样酸化过滤后用Oasis HLB固相萃取小柱净化富集,采用液相色谱-串联质谱法同时测定地表水中微囊藻毒素(MC-LR和MC-RR),通过优化试验条件,使方法在1.00μg/L~100μg/L范围内线性良好。MC-LR和MC-RR在水中的方法检出限为0.12 ng/L和0.2 ng/L,空白加标回收率为72.7%~88.5%,3次测定结果的RSD为9.1%~10.7%。将该方法用于6个海河流域部分重要水源地水样的监测,虽然部分水样中检测出MC-LR和MC-RR,但检出值均低于标准限值。  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.
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   

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.
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.
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   

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 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.
An ambient air quality study was undertaken in two cities (Pamplona and Alsasua) of the Province of Navarre in northern Spain from July 2001 to June 2004. The data were obtained from two urban monitoring sites. At both monitoring sites, ambient levels of ozone, NOx, and SO2 were measured. Simultaneously with levels of PM10 measured at Alsasua (using a laser particle counter), PM10 levels were also determined at Pamplona (using a beta attenuation monitor). Mean annual PM10 concentrations in Pamplona and Alsasua reached 30 and 28 μg m−3, respectively. These concentrations are typical for urban background sites in Northern Spain. By using meteorological information and back trajectories, it was found that the number of exceedances of the daily PM10 limit as well as the PM10 temporal variation was highly influenced by air masses from North Africa. Although North African transport was observed on only 9% of the days, it contributed the highest observed PM10 levels. Transport from the Atlantic Ocean was observed on 68% of the days; transport from Europe on 13%; low transport and local influences on 7%; and transport from the Mediterranean region on 3% of the days. The mean O3 concentrations were 45 and 55 μg m−3 in Pamplona and Alsasua, respectively, which were above the values reported for the main Spanish cities. The mean NO and NO2 levels were very similar in both sites (12 and 26 μg m−3, respectively). Mean SO2 levels were 8 μg m−3 in Pamplona and 5 μg m−3 in Alsasua. Hourly levels of PM10, NO and NO2 showed similar variations with the typically two coincident maximums during traffic rush hours demonstrating a major anthropogenic origin of PM10, in spite of the sporadic dust outbreaks.  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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