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1.
干扰曲线扣除法测定间硝基苯胺和间二硝基苯   总被引:1,自引:1,他引:0  
用比色法测定间二硝基苯和间硝基苯胺时,间硝基苯胺严重影响间二硝基苯的测定.本文采用标准曲线扣除法,可定量地描述间硝基苯胺对间二硝基苯的影响程度.用这种方法测定间硝基苯胺,其标准差为0.18μg,变异系数为0.9%,回收率为97.73%;测定间二硝基苯,其标准差为1.21μg,变异系数为6.0%,回收率为94.9%.  相似文献   

2.
原子荧光光谱法测定水中低含量锡   总被引:4,自引:0,他引:4       下载免费PDF全文
采用原子荧光光谱法测定水中锡,结果表明,方法检测限为0.14μg/L,在0、0μg/L~100μg/L范围内线性良好。不同浓度标准溶液测定的相对误差≤2.0%,实际样品测定的加标回收率在90.0%~109%之间,相对标准差≤6.1%,准确度和精密度均较好。  相似文献   

3.
建立了固相萃取-毛细管气相色谱测定地表水中硝基苯类化合物的方法,优化了试验条件。方法线性良好,10种硝基苯类化合物的检出限为0.05μg/L~0.15μg/L,实际样品测定的RSD为1.7%~5.0%,平均加标回收率为80.8%~117%。  相似文献   

4.
本文选用壁涂OV—17的弹性石英毛细管柱做为分离柱,多种的苯系物不干扰测定。空气中微量的硝基苯用苯收集,富集后的硝基苯直接进色谱测定。本方法在0.05μg/ml—100μg/ml范围内呈线性,相对标准偏差4.2%,回收率大于90%,检出限3.5×10~(-3)μg。采样10.5L时,最低检出浓度为0.001mg/m~3。  相似文献   

5.
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   

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.
以洪泽湖中6种代表性生物为研究对象,采用超声波法提取样品中硝基苯类化合物,用凝胶色谱净化、浓缩,气相色谱/质谱联用法测定。该法与索氏提取法在同等试验条件下进行加标回收试验,前者回收率高且稳定,简便可行。方法检出限为0.008μg/g~0.030μg/g,平均加标回收率为76.5%~109%,重复测定3次的RSD为1.5%~13.0%。  相似文献   

8.
工业废水中苯胺、硝基苯的检测方法探讨   总被引:2,自引:0,他引:2  
建立了用气相色谱内标法测定工业废水中的苯胺、硝基苯的方法,优化了试验条件。采用SE-30毛细管柱来代替不锈钢柱,并采用氢火焰离子化检测器,可快速测出工业废水中的苯胺、硝基苯含量。方法在0-400mg/L之间,线性关系良好,实际工业废水样品测定的CV≤1.44%,加标回收率为98.4%~99.3%。  相似文献   

9.
建立了固相微萃取与车载气相色谱-质谱联用技术现场快速定量分析突发性水环境污染事故中的硝基苯、苯酚、苯胺3种半挥发性有机物的方法。选用PA萃取纤维,调节水样p H为8.5,加入30%的氯化钠,45℃顶空萃取30 min可得最佳萃取效果。在最佳实验条件下,硝基苯、苯酚、苯胺的方法检出限分别为0.68、3.2、4.88μg/L;平行测定7次的相对标准偏差分别为5.37%、8.31%、2.86%;3种化合物的相关性系数均大于0.99;对实际样品测定的加标回收率在61.1%~120%。  相似文献   

10.
SPE-GC-ECD法测定水体中五种硝基苯类化合物   总被引:3,自引:0,他引:3  
建立了固相萃取(SPE)-气相色谱-电子捕获检测器(GC-ECD)检测水中硝基苯类的方法。5种硝基苯类化合物的测定在一定浓度范围内线性关系良好,在高、中、低3种浓度水平下,被测物的回收率在71.6%~87.8%之间,测定结果的相对标准偏差在1.6%~9.3%之间。5种硝基苯类的方法检出限分别为0.15μg/L和0.015μg/L。结果表明,该方法适用于实际水样中硝基苯类的测定。  相似文献   

11.
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:29,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   

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.
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   

14.
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   

15.
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   

16.
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   

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.
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   

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.
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   

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