共查询到20条相似文献,搜索用时 226 毫秒
1.
采用通常分析无机阴离子时的YSA阴离子分离柱,使用四硼酸钠淋洗液,可对降水中的甲酸、乙酸、F-等离子同时进行分析.其它无机阴离子不干扰测定.本方法可测定浓度为ppm或PPb级的有机酸,变异系数在2.3%以下,精密度良好. 相似文献
2.
3.
4.
建立超声提取-离子色谱法55 min内同时测定大气PM_(2.5)中13种水溶性低分子有机酸和无机阴离子的方法,经不同样品膜空白值考察、预处理条件优化、样品保存实验研究等获得了最佳的实验条件。研究发现,无机阴离子线性回归系数均为0.999以上,有机酸均为0.993以上;样品膜中各离子的相对标准偏差为3.2%~9.8%,样品提取液中各离子的加标回收率为90.6%~108%;当采样体积为24 m~3时,各目标化合物的方法检出限为0.003~0.032μg/m~3。分别于2015年1、6月采集了PM_(2.5)实际样品,1月各离子浓度之和为31.9μg/m~3,范围为0.04~15.0μg/m~3;6月各离子浓度之和为22.3μg/m3,范围为0.01~12.7μg/m~3。两个采样期间,氯离子、硝酸根、硫酸根在13种化合物中占绝对优势,均占总量的95%以上;乙酸、甲酸、甲烷磺酸和乙二酸为其他低含量离子中的主要组分。 相似文献
5.
兰州市降水化学特征研究 总被引:2,自引:0,他引:2
张宁 《甘肃环境研究与监测》1996,9(4):1-5
对兰州市的114个雨雪样品进行了8种无机阴离子,5种阳离子和2种有机酸离子的全面分析和测定。并对其季节变化,离子构成特征,降水中的有机酸,同时结合TSP水溶性离子状况以及降水天气气候特征进行了综合分析和研究。 相似文献
6.
7.
微波提取高效液相色谱法测定土壤中15种痕量多环芳烃 总被引:6,自引:1,他引:5
采用微波提取结合高效液相色谱技术测定了土壤中15种PAHs的含量.比较了用微波提取、索氏提取和超声萃取3种土壤样品的前处理方法对多环芳烃测定的影响,考察了色谱柱的性能、梯度洗脱条件的优化、荧光检潮波长程序变换及柱温等因素对15种PAHs组分之同分离的影响.经优化后的HPLC方法对15种PAHs的最低检测限为0.10~0.80 μg/kg,相对标准偏差为0.60%~4.60%,方法的回收率为58.1%~97.8%.实验结果表明,该方法兵有高效、快速、灵敏等特点,可以用于环境土壤样品中痕量PAHs的检测. 相似文献
8.
离子色谱法测定丙烯酸丁酯生产废水中丙烯酸和对甲基苯磺酸 总被引:4,自引:1,他引:3
建立了用离子色谱法测定丙烯酸丁酯生产废水中丙烯酸和对甲基苯磺酸的新方法。采用IonPac AS11-HC阴离子色谱柱,淋洗液为30mmol/L的NaOH淋洗液,流速1ml/min,抑制电流75mA。丙烯酸根的检测下限为0.44mg/L(峰面积)、0.46mg/L(峰高),保留时间、峰高、峰面积的变异系数分别为0.03%、0.50%、0.50%,峰高、峰面积的线性回归系数R分别为0.9929、0.9954。对甲基苯磺酸根的检测下限为0.49mg/L(峰面积)、0.48mg/L(峰高),保留时间、峰高、峰面积的变异系数分别为0.02%、0.48%、0.47%,峰高、峰面积的线性回归系数R分别为0.9990、0.9998。常规无机阴离子对丙烯酸、对甲基苯磺酸的测定没有干扰。对实际废水样品进行分析,丙烯酸、对甲基苯磺酸的回收率分别为101.6%~104.4%、95.4%~96.8%。方法简便、灵敏、可靠。 相似文献
9.
10.
梯度淋洗离子色谱法测定饮用水中6种阴离子 总被引:1,自引:0,他引:1
采用离子色谱法同时测定饮用水中F-、Cl-、Br-、NO3-、SO24-、PO34-等6种阴离子,水样经0.22μm滤膜过滤,自动淋洗发生器产生20 mmol/L~40 mmol/L KOH淋洗液梯度洗脱,在流量0.25 mL/min条件下采用IonPac AG19保护柱和IonPac AS19分离柱分离和定量。方法线性良好,6种阴离子的检出限为0.005 mg/L~0.057 mg/L,标准溶液平行测定6次,测定值的RSD在0.5%~2.2%之间,水样加标回收率在83%~106%之间。 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.
Topsoil and Housedust Metal Concentrations in the Vicinity of a Lead Battery Manufacturing Plant 总被引:2,自引:0,他引:2
John S. Rieuwerts Margaret Farago Vladimir Bencko 《Environmental monitoring and assessment》1999,59(1):1-13
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
13.
An Overview of Contaminant-Related Issues Identified by Monitoring in San Francisco Bay 总被引:1,自引:0,他引:1
Bruce Thompson Rainer Hoenicke Jay A. Davis Andrew Gunther 《Environmental monitoring and assessment》2000,64(1):409-419
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.
Biomagnification factors (fish to Osprey eggs from Willamette River,Oregon, U.S.A.) for PCDDs,PCDFs, PCBs and OC pesticides 总被引:3,自引:0,他引:3
Henny CJ Kaiser JL Grove RA Bentley VR Elliott JE 《Environmental monitoring and assessment》2003,84(3):275-315
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.
Achim Lohmeyer Wolfgang Baechlin Matthias Ketzel 《Environmental monitoring and assessment》2000,65(1-2):381-387
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.
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
17.
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
18.
Ellis A. M. Franssen Brigit A. M. Staatsen Erik Lebret 《Environmental Impact Assessment Review》2002,22(6)
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside. 相似文献
19.
Clifford A. Hui John Y. Takekawa Sarah E. Warnock 《Environmental monitoring and assessment》2001,71(2):107-121
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05). 相似文献
20.
火焰原子吸收光谱法测定苏州开发区26种蔬菜中铜锌铁锰镍 总被引:6,自引:0,他引:6
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