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1.
原子荧光光谱法测定废水样品中的汞   总被引:1,自引:0,他引:1  
应用AFS-220型双道原子荧光光谱仪,研究了有色冶炼废水样品中汞的测定技术。将废水样品以适量硝酸酸化,加入高锰酸钾使汞成为离子状态,再以硼氢化钾(KBH4)为还原剂,在硝酸介质中测定汞,回收率为91~95%,最低检出限可达0.0002μg/ml。  相似文献   

2.
应用气相色谱(GC)Ni63电子捕获检测器(ECD),在6201红色担体为基体,涂10%OV-101固定液的玻璃柱上,以甲苯作吸收液,对大气环境中微量二硫化碳能够进行定量检测,其最低检出浓度可达6×10-6mg/ml(进液体样品1μl);方法精密度为3.4%,SO2、H2S气体物质不干扰测定。经现场实际环境样品测试,此方法能够适用于大气环境中微量CS2的分析工作,为大气环境监测微量CS2的分析建立了一个比较合适的方法。  相似文献   

3.
发生氢气分离离子色谱法间接测定水中硫化物   总被引:1,自引:0,他引:1  
利用KBH4在酸性条件下分解产生的氢气为载气分离水中硫化物,用NaOH—H2O2溶液吸收H2S,并将其氧化为SO2-4,用离子色谱法测定SO2-4。方法用于各种水样中硫化物的测定,相对标准偏差为1.58%,回收率在90.5%到98.2%之间。方法适用于水中硫化物的测定  相似文献   

4.
石墨炉原子吸收光谱法测定土壤中的微量砷   总被引:6,自引:0,他引:6  
土壤样品经HNO3-HCIO4消解处理后,采用Ni作为基体改进剂,偏振塞曼效应扣去背景,实现了砷的石墨炉原子吸收法的直接测定。该方法操作简单,干扰少,灵敏度高,砷的检测下限为0.7ng/ml,样品分析回收率94%-108%,相对标准偏差5.1%。  相似文献   

5.
石莹 《干旱环境监测》1994,8(3):160-162
探讨了一种简便的医院污水BOD测定中样品稀释倍数的推算方法。首先测定CODCr值,由CODCr值除以系数8,即获得稀释倍数C=CODCr/8。结果表明,该法仅需配制一个稀释比,省时省力,并具有可靠性好,准确度高,适应性强等优点。适用于各种医院污水中BOD的分析监测。  相似文献   

6.
PTA废水的TOC测定及其与COD的相关性   总被引:6,自引:0,他引:6       下载免费PDF全文
长期以来 ,国内一般采用BOD5 和COD作为评价水体污染的综合指标。但是 ,仅测定BOD5 和COD不能全面准确地反映废水中不同有机污染物质对水体的污染程度 ,而测定总有机碳 (TOC)能够较好地反映之 ,并且可以通过专用仪器快速测定。1 TOC的测定1 .1 主要仪器与试剂1 0 2 0型TOC测定仪 ,美国O .I公司 ;1 0 5 0型自动进样器 ,美国O .I公司 ;无水碳酸钠 :GR ;苯二甲酸氢钾 :GR ;氢氧化钠 :AR ;85 %磷酸 ;36%盐酸。1 2 方法原理TOC测定采用高温燃烧—非分散红外吸收法将样品注入燃烧炉 ,在温度 680℃~ 95 0℃…  相似文献   

7.
合成了新试剂4-(H-酸偶氮)1-苯基-3-甲基吡唑酮(HPMP),研究了其和铜的显色反应。在pH=7的NH4Ac缓冲介质中,CTMAB存在下,HPMP与Cu(Ⅱ)生成2∶1紫色络合物,λmax=580nm,ε=5.68×104L·mol-1·cm-1。铜含量在0~0.6mg/L内符合比耳定律。方法用于水样和生物样品中铜的测定,结果令人满意。  相似文献   

8.
Bi(Ⅱ)──APDC共沉淀富集脱脂棉分离FAAS测定水中痕量Pb、Cd王林涛,杨玲(云南玉溪地区环境监测站,653100)取加热浓缩至20ml的水样,加入Bi(Ⅱ)(100μg/ml)3ml、APDC3ml,NaOACHOAC缓冲液2ml,调pH至...  相似文献   

9.
模型公式法在确定BOD_5样品稀释系数中的应用   总被引:1,自引:0,他引:1  
本文提出了一种利用以往监测数据计算BOD5稀释系数的简易公式,为BOD5测定中稀释系数的确定提供了一种科学准确的计算方法。本法不受经验因素的限制,并能确保BOD5样品分析的可靠性与成功率,具有应用与推广价值。  相似文献   

10.
超临界二氧化碳萃取-GC/MS测定土壤中的多环芳烃   总被引:12,自引:2,他引:10  
本文开发了一种采用超临界二氧化碳萃取土壤中多环芳烃、不须经过纯化步骤,直接可用于GC/MS分析的简便、高效的方法。本实验中超临界革取的流体是二氧化碳,改善剂是5%的二氯甲烷/甲醇,萃取温度为120℃、压力为34MPa。GC/MS分析时除了采用外标外,还加入了6种同位素PAHs内标以校正各段PAHs的响应因子。采用本方法成功地测定了我国未开垦森林土壤中的PAHs。  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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