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1.
采用离子对高效液相色谱法同时测定氧化型染发剂中5种染料成分,选择Phenomenex kinetex C18色谱柱(2.6μm,4.6 mm×150 mm),以10 mmol/L辛烷磺酸钠水溶液(pH值2.5)+甲醇(体积比60∶40)为流动相,采用DAD检测器,检测波长280 nm,以保留时间和紫外光谱特征定性,外标法定量。5种染料在20.0 mg/L~100 mg/L范围内线性关系良好,最低检出质量分数氢醌为0.02%,间苯二酚为0.03%,邻氨基苯酚为0.02%,邻苯二胺为0.04%,4-氨基-2-羟基甲苯为0.03%。低浓度基质加标平均回收率为82.5%~106%,RSD为1.4%~6.1%,中浓度基质加标平均回收率为82.0%~105%,RSD为0.4%~2.2%,高浓度基质加标平均回收率为78.5%~105%,RSD为1.7%~4.5%。  相似文献   

2.
怠速工况下汽车使用乙醇汽油排放污染物的变化   总被引:2,自引:0,他引:2  
对怠速工况下使用乙醇汽油汽车尾气中污染物进行了检测.结果表明,使用乙醇汽油后,汽车尾气中CO和HC浓度明显降低,平均下降率为56.9%和38.2%;NOx平均下降率为15.0%;CO2浓度平均增长率为5.04%;苯系物浓度明显降低,平均下降率在45.5%~53.1%;醛类的浓度增加明显,平均增长率在47.8%~293%;丙酮、丁酮的浓度增加,分别为16.6%和25.3%.  相似文献   

3.
2018年夏季上海合作组织成员国元首理事会环境空气质量保障工作开始前,中国监测总站对山东、江苏2个省份19个城市共计85个国控站点开展O3专项质控工作。结果表明,保障区域O3监测数据低、中、高浓度点相对误差变异系数分别为4. 7%、4. 3%和4. 8%,95%预测区间分别为[-7. 4%,9. 0%]、[-6. 9%,8. 3%]和[-8. 0%,8. 4%]。与之相比,2018年全国范围内开展外部比对的1 346个国控站点O3监测数据低、中、高浓度点相对误差变异系数分别为7. 4%、6. 5%和6. 2%,95%预测区间分别为[-13. 1%,15. 4%]、[-11. 7%,13. 2%]和[-11. 6%,12. 2%]。通过专项质控工作,保障区域O3监测数据质量明显提升,能够为夏季重大活动保障提供更为准确、可比的O3监测数据支持。  相似文献   

4.
贵州省典型农业区土壤重金属污染及在蔬菜中的富集研究   总被引:6,自引:0,他引:6  
选择贵州省遵义县4个镇典型农业区,研究重金属含量和污染特征以及在蔬菜中的富集作用.结果表明,由于贵州省重金属本底值普遍较高,遵义县虾子镇、永乐镇、新舟镇和喇叭镇土壤Cd、Hg、As均有超标,Cd的超标率分别为64.3%、31.3%、23.5%和6.3%,Hg的超标率分别为37.5%、11.8%、12.5%和28.6%,As的超标率分别为6.3%、23.5%、31.3%和28.6%;从蔬幕对重金属的富集作用来看,辣椒、西红柿对于Cd有较强的富集作用,豇豆对As的富集系数略高于其它蔬菜,黄瓜、豇豆对Hg的富集强于对其它重金属元素的富集.  相似文献   

5.
土壤介质中酞酸酯类污染物分析方法研究   总被引:4,自引:2,他引:2  
介绍了加压流体提取(PFL、ASE)提取-GPC净化-GC/MS分析土壤中酞酸酯类污染物方法的程序和质控要求,研究了每个步骤对分析六种目标物准确度和精密度的影响以及测定实际土壤样品的情况.结果显示,加压流体提取(PFL)、浓缩和GPC净化各步骤全程序空白加标回收率分别在86.3%~108%、78.5%~117%和87.4%~103%范围,精密度均在15%以内.在实际土壤样品中加入六种酞酸酯标准的加标回收率在45.2%~103.4%范围内,其相对标准偏差8%~23%.  相似文献   

6.
以四川省南充市为研究区域,通过实地调研、现场测试及结合统计年鉴等获得数据,采用排放因子法计算南充市2014年大气PM_(10)、PM_(2.5)排放量并建立排放清单。结果表明,南充市2014年扬尘源、移动源、生物质燃烧源、化石燃料固定燃烧源、工艺过程源排放总量PM_(10)分别为85 187、1 777、9 175、2 417、3 519 t,PM_(2.5)分别为16 093、1 619、7 322、914、1 585 t,PM_(10)贡献率分别为83.5%、1.7%、9.0%、2.4%、3.4%,PM_(2.5)贡献率分别为58.4%、5.9%、26.6%、3.3%、5.8%。城市区域扬尘源、生物质燃烧源、移动源、化石燃料固定燃烧源、工艺过程源对PM_(10)贡献分别为60.0%、12.5%、6.3%、8.6%、12.5%,对PM_(2.5)贡献分别为41.8%、21.6%、14.4%、8.1%、14.1%。南充市2014年大气PM_(10)、PM_(2.5)排放源总量和贡献率以及区域空间分布特征均存在差异。  相似文献   

7.
为研究西北地区封闭式湖泊水质恶化原因及水体污染物迁移转化规律,以宁夏沙湖为研究对象,对沙湖2012—2017年水体污染物总量变化趋势及沙湖周边地表水环境质量进行分析。研究结果表明:沙湖水环境质量变化主要由内源性污染和外源性输入造成,其中内源性污染源主要为沙湖沉积物污染物释放,沙湖水体沉积物通过孔隙水向沙湖水体转移的CODMn、CODCr、TP、TN、氟化物分别占水体总污染物的6.4%、6.6%、16.6%、14.2%、31.4%;沙湖外源性污染源主要为黄河补水和农垦集团稻田等面源污染,其中黄河补水向沙湖 转移的 CODMn、CODCr、TP、TN、氟化物分别占沙湖水体污染物总量的49%、30%、279%、99%、13%,沙湖周边面源性污染通过渗透作用向沙湖水体输入的CODMn、CODCr、TP、TN、氟化物分别占沙湖水体污染物总量的23%、18%、52%、34%、19%,外源性污染物输入占沙湖水体污染物总量CODMn、CODCr、TP、TN、氟化物分别为72%、48%、331%、133%、32%,但由于水体自身净化作用, TP和TN已大幅度降解。  相似文献   

8.
对便携式催化氧化-FID法测定非甲烷总烃的检出限、精密度、准确度、催化效率等性能指标开展研究,考察该方法测定固定污染源废气中非甲烷总烃的适用性。结果表明:催化氧化装置的转化效率为98.1%~99.7%,方法检出限为0.05 mg/m3(以碳计);2个质量浓度水平的甲烷和丙烷混合标准气体测定结果的相对误差分别为-6.4%~6.1%、-4.7%~-0.5%,实验室内、实验室间测定结果的RSD分别为2.9%~5.9%和1.6%~2.5%、1.5%和0.6%。用该方法和国标法同时测定实际样品,两种方法测定结果的相对误差为6.4%~21.4%。  相似文献   

9.
建立了以液-液萃取、三重串联四极杆气相质谱多反应监测法同时测定饮用水源地水体中18种多氯联苯的方法,给出了测量线性范围,线性关系良好,相关系数大于0.998。水中加标浓度为1.00、5.00、10.0ng/L时,平均加标回收率分别为75.6%~96.0%、90.6%~105%和92.4%~102%,相对标准偏差分别为19.8%~11.8%、4.2%~12.9%和4.3%~9.9%,检出限为0.29~0.57ng/L。结果表明,在测定水体中痕量多氯联苯方面,三重串联四极杆气相质谱相对于气相色谱-电子捕获检测和气相色谱质谱-选择离子检测具有更高的灵敏度和准确度,具有更广泛的应用。  相似文献   

10.
微波消解平台石墨炉原子吸收法测定活性污泥中重金属   总被引:10,自引:0,他引:10  
以铜和铅为例建立了一种微波消解样品,平台石墨炉原子吸收法测定活性污泥中重金属含量的方法,该方法的样品加标回收率Cu为91 0%~97 3%,Pb为93 1%~98 0%,相对标准偏差RSD(%):Cu为1 38%~1 61%,Pb为1 28%~1 94%,检验限Cu为0 0052ng g,Pb为0 0073ng g,该方法应用于活性污泥中重金属的分析,实验所需时间短,取样量少,空白值低,实验过程中样品损失小,准确度和灵敏度高,结果令人满意。  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.
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:24,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   

13.
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   

14.
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   

15.
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   

16.
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   

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 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.
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   

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