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1.
建立了GDX 502管吸附-二氯甲烷解吸-气相色谱测定气中吡啶的方法,考察吸附管类型、解吸溶剂、解吸溶剂体积、采样时间和采样流量对测定结果的影响。结果表明,气中吡啶用GDX 502吸附管以0. 5 L/min的流量采样20 min,二氯甲烷解吸至1 m L,DB-1 (30 m×250μm×0. 25μm)柱分离,空白样品低、中、高3种加标量回收率为90. 8%~108%(n=6),相对标准偏差为2. 9%~4. 4%,方法在0~19. 6 mg/L线性范围内响应良好,相关系数(r)=0. 999 9。当采样体积为10 L时,检出限为0. 01 mg/m~3。该方法重复性好、回收率高、干扰较小,能够满足空气和废气中吡啶分析的要求。  相似文献   

2.
热脱附-气相色谱法测定环境空气中芳烃和卤代烃   总被引:15,自引:3,他引:15  
建立了热脱附-气相色谱法测定环境空气中9种芳烃和卤代烃方法。阐述了样品管制备、采样袋预处理、现场采样和实验富集等过程。采用保留时间定性、外标法定量。进行了自动热脱附仪的吸附和解吸效率的试验,各组分的吸附效率均在97%以上,解吸效率达98 9%。最低检出质量浓度氯乙烯为0 0003mg/m3、1,2-二氯乙烷和1,2-二氯丙烷为0 0002mg/m3、苯、甲苯、乙苯、对二甲苯、苯乙烯和邻二甲苯均为0 0001mg/m3。试图以不更换TenaxTA吸附剂标准冷阱来测定齐鲁石化环境空气中特征污染物乙烯,由于冷阱对乙烯的二级吸附未能很好地解决,试验效果不理想,有待进一步研究。  相似文献   

3.
建立了一种利用活性炭管采样,二硫化碳洗脱,DB-624UI气相色谱柱(30 m×0.25 mm×1.4μm)进行分离,FID检测器检测的测定环氧丙烷和环氧氯丙烷的气相色谱方法。结果显示,环氧丙烷和环氧氯丙烷在0.5~50 mg/L范围内线性关系良好,方法检出限达到了0.026 mg/m3和0.048 mg/m3(以采集4.5 L空气样品计);环氧丙烷平均解析效率84.84%(RSD=1.770),环氧氯丙烷平均解析效率92.07%(RSD=2.270),适用于工作场所中环氧丙烷和环氧氯丙烷的同时测定。  相似文献   

4.
环境空气中丙烯酸乙酯的气相色谱法测定   总被引:4,自引:1,他引:3  
建立了环境空气中丙烯酸乙酯的TenaxGC吸附 -热解吸气相色谱测定方法。方法回收率为 87 3%~1 0 7 1 % ,变异系数为 5 3%~ 7 2 %。当采样体积为 2L时 ,检测限为 0 0 2mg/m3,具有采样时间短 ,不用任何溶剂等特点。  相似文献   

5.
采用毛细管柱气相色谱法测定环境空气中的1,2-二氯乙烷,用活性碳吸附,二硫化碳解析,FID检测器分析.方法在0 mg/L~311mg/L范围内线性良好,当采样体积为20 L时,最低检出质量浓度为0.006 mg/m3,标准溶液平行测定的RSD≤2.2%,加标回收率为98.4%~101%.  相似文献   

6.
1四氯化碳应进行蒸馏或用经 30 0℃高温活化后的活性炭吸附后并经检验合格方可使用。 2地表水采样应在水下 2 0~ 5 0 cm处 ,污染源采样应在采样处做一个水跃区 ,使油水混合均匀后采样 ,最好用大口带刻度玻璃瓶采样 ,样品采集后不得分装。 3水样如不能在 2 4小时内测定 ,采样后  相似文献   

7.
研究了SUMMA罐采样-全二维气相色谱-飞行时间质谱法测定环境空气中有机硫化物。采用SUMMA罐采集样品,自动进样器进样,三级冷阱预浓缩样品,全二维气相色谱-飞行时间质谱法(GC×GC-TOFMS)测试分析,以较长的非极性柱Rxi-5MS(30 m×320μm×1.0μm)作为第一维柱,较短的中等极性柱DB-17MS(2.0 m×0.1 mm×0.1μm)作为第二维柱,对环境空气中的有机硫化物进行了定性定量分析。结果表明,该方法特性不仅满足方法学要求,而且比《空气和废气监测分析方法》(第4版)推荐的方法更加优异,能够准确、快速地检测环境空气中有机硫化物。  相似文献   

8.
用GC-MS测定空气中丙烯酸酯类污染物   总被引:3,自引:0,他引:3  
采用活性碳吸附-二硫化碳解吸,GC-MS法测定空气中丙烯酸酯类污染物,采样体积为2h时,定量下限为0.5~1.6μg/m3。在吸附总量小于5mg时,活性碳吸附效率几近100%。CS2提取效率也都在95%以上。方法相对标准偏差为0.5%~3%,回收率为95%~109%。  相似文献   

9.
液相色谱法测定环境空气中酞酸酯类   总被引:1,自引:0,他引:1  
制作了半挥发性有机物中流量采样装置,使用超细玻璃纤维滤膜采样,反相液相色谱法测定环境空气中酞酸酯类,并对样品净化方式、目标化合物在气相和颗粒物上的分布规律及采样器的捕集效率进行了试验.方法在0.50 mg/L~50.0 mg/L之间线性关系良好,当浓缩体积为1.0 mL、采样体积为144 m3时,目标化合物的检出限为0.4×10-3 μg/m3~6.0×10-3 μg/m3;当采样体积为6 m3时,检出限为0.008 μg/m3~0.145 μg/m3.  相似文献   

10.
过氯乙烯滤膜采样-酸消解-钼蓝光度法测定磷酸雾   总被引:1,自引:0,他引:1  
建立了过氯乙烯滤膜采样 -酸消解 -钼蓝分光光度法测定磷化车间磷酸雾的监测方法。实验室模拟采样的捕集效率为 95 7%~ 99 1 %。单个实验室对含 5μg和 1 5μg样品进行多次测定 ,其相对标准差小于 5% ,样品加标回收率为 98 2 %~ 1 0 0 5% ,方法检测限为 0 0 0 7mg/m3。对标样测定 ,结果均在给定值范围内。用该法与等离子发射光谱法(ICP)对 5个样品进行比对测定 ,结果均令人满意。  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.
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:25,自引:5,他引:25       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 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.
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   

16.
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   

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.
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   

19.
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   

20.
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   

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