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1.
水样经HLB小柱富集、净化后,采用高效液相色谱-四极杆-高分辨飞行时间质谱同时测定水样中MC-LA、MC-LF、〖JP3〗MC-LR、MC-LW、MC-LY、MC-RR、MC-YR、MC-WR等8种微囊藻毒素。试验表明,8种微囊藻毒素在0500 μg/L~〖JP〗100 μg/L范围内线性良好,方法检出限为0001 μg/L~0005 μg/L,自来水空白样品3个质量浓度水平的加标回收率为725%~998%,5次测定结果的RSD为19%~112%。将该方法用于测定珠海本地水产养殖鱼塘和小型水库的水样,结果均未检出  相似文献   

2.
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   

3.
采用快速溶剂萃取-固相萃取-液相色谱串联质谱法(LC-MS/MS)测定土壤中8种多溴联苯醚类(PBDEs)化合物,通过优化试验条件,使方法在100 μg/L~1 000 μg/L范围内线性良好,方法检出限为085 μg/kg~125 μg/kg。不同土壤样品的8种多溴联苯醚回收率为68.6%~127%,4次测定结果的RSD为4.8%~27.6%。将该方法用于测定电子废物拆解点周边的土壤样品,结果BDE-209测定值为未检出~168 μg/kg,BDE-183为未检出~560 μg/kg,其余6种BDEs均为未检出。  相似文献   

4.
在碱性条件下,NBS直接氧化腐殖酸产生强烈的化学发光信号,结合流动注射技术,建立了测定土壤腐殖酸含量的流动注射化学发光分析法并详细研究了影响化学发光信号强度的各种因素。方法的测定线性范围为1.0×10-7-1.0×10-3g/ml,检出限(3σ)为3×10-8g/ml。对5.0×10-5g/ml的腐殖酸进行11次平行测定,相对标准偏差为1.8%。将该法用于实际土壤样品分析,结果令人满意。  相似文献   

5.
在乙二胺 (en)介质中 (p H1 1 .5~ 1 2 .3 ) ,Zn(en) 2 +3在单扫描示波极谱仪上于 -1 .42 V(vs.SCE)处产生一灵敏的络合物吸附波 ,锌含量在 0 .0 0 6~ 0 .3 5 μg/ml范围内 ,浓度与峰电流呈线性关系。检测限为 0 .0 0 3 μg/ml。加标回收率为92 %~ 1 0 3 % ,相对标准偏差小于 4.1 %。该方法准确、简便、选择性好 ,可用于 TSP中微量锌的测定。  相似文献   

6.
毛细管气相色谱法测定水中氯苯类化合物   总被引:4,自引:2,他引:4       下载免费PDF全文
采用毛细管气相色谱法同时分离测定水中11种氯苯类化合物.用DB-23毛细管柱分离,电子捕获检测器检测,方法线性关系良好,水中氯苯类的最低检出限分别为:二氯苯0.74 μg/L~0.89 μg/L,三氯苯0.17 μg/L~0.21 μg/L,四氯苯0.07 μg/L~0.11 μg/L,五氯苯0.04 μg/L、六氯苯0.02 μg/L,加标回收率在83.5%~101%之间,RSD在1.4%~5.2%之间.  相似文献   

7.
HPLC法测定饲料中维生素A、维生素D 3 和维生素E   总被引:2,自引:0,他引:2       下载免费PDF全文
建立了以w(C2H5OH)=95 %乙醇直接提取,高效液相色谱仪在波长280 nm和254 nm处连续测定饲料中维生素A、维生素D3和维生素E的方法.色谱柱为大连依利特Hypersil ODS C18(25 cm×4.6 mm×5 μm),流动相为甲醇-水,流速为1.2 mL/min.维生素A、维生素D3、维生素E的质量浓度分别在1.0 mg/L~20.0 mg/L、0.5 mg/L~15.0 mg/L 、2.5 mg/L~50.0 mg/L范围内与峰面积呈良好的线性关系,检测限分别为0.3×10-6 μg、0.04×10-6 μg、5.0×10-6 μg,相对标准偏差分别为1.6 %、2.7 %、2.4 %,平均回收率分别为99 %、102 %、98 %.  相似文献   

8.
采用固相萃取处理水样,超高效液相色谱-四极杆-飞行时间质谱法(UPLC-QTOF-MS)测定水样中14种全氟有机酸。通过优化试验条件,使方法在100 μg/L~100 μg/L范围内线性良好,方法检出限为087 μg/L~480 μg/L。空白水样的加标回收率为808%~113%,测定结果的RSD≤37%。将该方法用于测定厦门市某大学周边水样,结果14种全氟有机酸均为未检出。  相似文献   

9.
原子荧光光谱法同时测定环境水体中痕量锡和锌   总被引:1,自引:0,他引:1       下载免费PDF全文
采用原子荧光光谱法同时测定环境水样中痕量锡和锌,优化了试验条件。锡在1.00μg/L~10.0μg/L、锌在20.0μg/L~200μg/L范围内线性良好,方法检出限锡为0.13μg/L,锌为1.76μg/L,锡和锌标准溶液测定的相对标准偏差分别为2.9%和4.0%,环境水样加标回收率锡为96.4%~106%,锌为92.0%~111%。  相似文献   

10.
九龙江龙岩段地表水中多环芳烃分布与污染源解析   总被引:2,自引:2,他引:0  
用竹炭固相萃取恒波长同步荧光法测定了九龙江龙岩段水体中16种优控多环芳烃(PAHs)的含量。结果表明:龙岩市省控断面河水中2010年11月(冬季)多环芳烃的质量浓度为58.3×10-9~1 328.5×10-9g/L,平均为387.72×10-9g/L;2011年9月(秋季)水中总多环芳烃质量浓度为5.9×10-9~188.4×10-9g/L,平均为77.46×10-9g/L;7月(夏季)多环芳烃的质量浓度为16.7×10-9~1 203.3×10-9g/L,平均为475.05×10-9g/L,同国内外河流相比,九龙江龙岩段水体中PAHs污染较严重,且具有明显的季节分布特征。夏、秋、冬季九龙江龙岩段水体水中均以3~4环PAHs为主。污染来源分析表明,河水中PAHs主要来源于燃烧源。  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.
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   

13.
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   

14.
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   

15.
土壤和底泥中砷、铬、锰测定的前处理技术   总被引:6,自引:0,他引:6  
试验了土壤和底泥中砷的前处理技术,其目的是能对土壤、底泥中砷、铬、锰在一次前处理中制备成试液,比色法分析。试验表明,用H2SO4-H3PO4-H2O2进行前处理是可行的。方法简单、挥发酸雾少,用标准参考物质检验证明,分解完全,数据准确,有粒较好一致性。  相似文献   

16.
This paper presents the chemical speciation and retention behavior of chromium (Cr), nickel (Ni), and cadmium (Cd) prior to and after the electrokinetic remediation in glacial till soil. The speciation of the metals was predicted using the chemical speciation program MINEQL+. The simulations were performed for single-contaminant with only Cr(VI) or Ni, and multi-contaminants consisting of: (1) Cr(VI), Ni, and Cd; (2) Cr(III), Ni and Cd; (3) Cr(VI), Cr(III), Ni and Cd; (4) Cr(VI), Ni, and Cd with reducing agents; and (5) Cr(III), Ni, and Cd with oxidizing agent (Mn). The results showed that the speciation and distribution of cationic metals [Ni, Cd, and Cr(III)] in glacial till soil remain unaffected or slightly affected during electrokinetics. This is attributed to the high pH buffering capacity of the glacial till, leading the metals to precipitate in the soil prior to and after electrokinetics. This study showed that during electrokinetics, Cr(VI) existed as anionic complex and migrated towards the anode and the migration is maximum in case of a single-contaminant system. The study also showed that near the anode in the absence of any reducing and oxidizing agent, Cr(VI) mostly adsorbed, and some of Cr(VI) reduced to Cr(III) and migrated towards the cathode and finally precipitated due to high pH conditions. Ni and Cd remain adsorbed or precipitated due to the high pH conditions throughout the soil. Among the reducing agents, the sulfide had significant effect on the migration of metals compared to ferrous ions. While in the presence of oxidizing agent (Mn), no noticeable Cr(VI) was found in the soil sample indicating the reduction of Cr(VI) to Cr(III) and the predominance of reducing conditions due to the presence of naturally occurring iron in the glacial till soil. Overall, this study provides a reasonable explanation of the speciation and distribution of chromium, nickel and cadmium during the electrokinetic remediation of glacial till soil.  相似文献   

17.
We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.  相似文献   

18.
Metal concentrations in deciduous tree leaves from urban areas in Poland   总被引:1,自引:0,他引:1  
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves.  相似文献   

19.
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ 15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ 15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ 15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ 15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ 15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R 2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ 15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ 15N of Spartina relates with the integrated, watershed-sea nitrogen inputs.  相似文献   

20.
We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soils.  相似文献   

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