首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
M-估计在水质监测中的应用   总被引:2,自引:0,他引:2  
M估计是极大似然估计的一种简称。以水质蒸馏后4氨基安替比林分光光度法测定挥发酚和纳氏试剂比色法测定氨氮为例,分别考察了M估计与传统的最小二乘法(LS)所获取的校准曲线方程。回收试验结果表明个别异常值(<30%)不影响M估计,而LS估计则不然,前者在水质监测中的稳健性亦得以充分证明  相似文献   

2.
空气中总悬浮颗粒物的X射线衍射定性分析研究   总被引:2,自引:0,他引:2  
以天津市环境监测中心采集的空气中总悬浮颗粒物(TSP)膜(971012号)为样品,使用日本理学D/maxRAX射线衍射仪对其进行化合物定性分析,并介绍样品的采集与制样方法、仪器测试条件。最后通过JCPDSICDD(国际粉末衍射数据中心)标准数据库检索出该样品所含的全部化合物  相似文献   

3.
GEMS/Water介绍(2)朱玉栋(中国环境监测总站,北京100012)GEMS/Water于1990年8月在前苏联的列宁格勒(圣彼得堡)召开了专家会议。对GEMS/Water自开始以来的第一阶段工作进行了总结,并对从1991年至2000年的第二阶...  相似文献   

4.
电线电缆行业漆包线生产工艺废气中有机物的GC/MS测定   总被引:1,自引:0,他引:1  
本文以活性炭、TenaxGC、聚氨酯泡沫为吸附材料,用二硫化碳洗脱、二氯甲烷提取、加热解吸三种脱附方式,并以色谱/质谱(GC/MS)联用仪为测试手段,对漆包线生产工艺废气中的有机物进行了测定,共检出72种有机化合物。本文进行了不同采集方式间的比较,提出了电线电缆行业工艺废气中有机化合物的系统分析方法。  相似文献   

5.
空气或废气中挥发性醛、酮的气相色谱法测定   总被引:4,自引:1,他引:3  
本文研究采用了空气或废气中挥发性醛、酮类化合物在常温下经2,4二硝基苯肼(DNPH)的酸性饱和溶液吸收,分别形成各自的腙,用CS2萃取后,经气相色谱法(GCFID)以3%SE30/ChromosorbWHP80100目为固定相和载体,分离测定,对空气或废气中的甲醛、乙醛、丙烯醛、丁醛、丙酮、丁酮、甲基异丁基酮等的测定,获得较满意的结果。  相似文献   

6.
本文报道了以7碘8羟基喹啉5磺酸作荧光增强剂的Zn、Al激光时间分辨荧光测定方法。方法检出限分别为25μg/L和10μg/L。用牛肝粉标准品(NBS1577a)进行了验证  相似文献   

7.
易江 《干旱环境监测》1996,10(2):110-112
燃煤(油)固定污染源二氧化硫排放总量监测(四)烟气采样器及其应用易江(中国环境监测总站100012)接1996,1O(1):45~487GM—100型、SGS一94型烟气采样器及其应用GM——100型、SGS—94型烟气采样器是吸收、消化国外先进技术...  相似文献   

8.
GEMS/Air介绍(1)1993年监测报告(I)朱玉栋(中国环境监测总站,北京100012)全球环境大气监测(简称为GEMS/Air)1993年在中国的工作情况如下;1.GEMS/Air监测站位情况目前在中国参加GEMS/Air工作的城市共有五个,...  相似文献   

9.
本文基于Hg(Ⅱ)meso四(3氯4甲氧基苯基)卟啉(T(3Cl4MOP)P)Twen80显色体系,提出一种高灵敏度二阶导数分光光度法测定工业废水中的痕量汞(Ⅱ),研究了汞配合物的形成条件。在pH72~79的中性介质中和Tween80的存在下,沸水浴加热6min,反应进行完全。汞(Ⅱ)量在18~104μg/L范围内符合比尔定律,二阶导数分光光度法测定汞(Ⅱ)的表观摩尔吸光系数ε4526,4616=988×106L·mol-1cm-1,检出限为18ng/ml。方法用于工业废水中痕量Hg(Ⅱ)的测定,结果满意。  相似文献   

10.
GEMS/Water介绍(1)朱玉栋(中国环境监测总站,北京100012)GLobaLEnvironmentalMonitoringSystem(简称为GEMS)是全球环境监测系统;GEMS/Water是全球环境监测系统中的水质监测,通常称为全球水质...  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.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号