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1.
采用小体积液液萃取-气相色谱/质谱联用法测定地表水中有机磷农药,以1.2 mL正己烷为萃取剂,磷酸三苯酯为内标,对8种目标化合物的富集倍数达156~436.方法在1.00 μg/L~20.0 μg/L范围内线性良好,8种有机磷农药的检出限均为0.2 μg/L,实际水样平行测定的RSD为2.1%~9.7%,平均加标回收率...  相似文献   

2.
采用固相微萃取-便携式气相色谱/质谱联用法(In situ SPME/GC-MS)分析地表水和废水中6种有机磷农药,通过优化测定条件,使6种有机磷农药在200 μg/L~500 μg/L范围内线性良好。方法检出限为033 μg/L~122 μg/L,低、高质量浓度标准溶液6次测定结果的RSD为68%~175%,加标回收率为849%~109%,与实验室方法的测定结果基本一致。  相似文献   

3.
采用气相色谱法测定土壤中37种有机磷农药,当取样量为10 g时,37种有机磷农药方法检出限为0. 002~0. 015 mg/kg,测定下限为0. 008~0. 060 mg/kg。低含量加标样品中有机磷农药的加标回收率为72. 8%~104%,相对标准偏差为4. 2%~13. 8%;中含量加标样品中有机磷农药的加标回收率为71. 5%~101%,相对标准偏差为4. 3%~13. 5%;高含量加标样品中有机磷农药的加标回收率为74. 6%~109%,相对标准偏差为6. 8%~14. 6%。该方法灵敏度高、分离效果好、重现性好,能够满足土壤中37种有机磷农药残留检测的要求。  相似文献   

4.
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   

5.
微波消解-原子荧光法测定土壤中汞、砷、硒   总被引:5,自引:3,他引:5  
建立了微波消解-原子荧光法测定土壤中汞、砷、硒的方法.汞在0.00 μg/L~1.00 μg/L、砷在0.00 μg/L~10.0 μg/L、硒在0.00 μg/L~2.00 μg/L之间线性关系良好,以称样0.200 0 g计,检出限汞为0.005 mg/kg,砷为0.009 mg/kg,硒为0.025 mg/kg.经国家有证标准物质验证,方法精密度与准确度均能满足土壤环境样品的测试要求.  相似文献   

6.
土壤样品用正己烷-丙酮(体积比为1∶1)混合溶液提取,配合硅胶小柱净化,用乙酸乙酯洗脱,再用气相色谱-火焰光度法测定待测液中14种有机磷农药残留,方法在0.100 mg/L~1.00 mg/L范围内线性良好,当取样量为10 g时,方法检出限为1.3μg/kg~2.3μg/kg。用该方法测定有机磷的有证标准溶液,结果均在保证值范围内,RSD为2.2%~6.7%。实际土壤样品的13种有机磷农药加标回收率为59.2%~125%(敌百虫除外),敌百虫回收率为0,说明目标物在测定过程中被降解,该方法不适用于敌百虫的测定。  相似文献   

7.
采用加压流体萃取〖CD*2〗气相色谱/质谱联用法(ASE GC/MS)测定土壤中9种半挥发性有机物,分别考察萃取条件、氮吹浓缩、硅酸镁小柱净化和浓缩定容等前处理条件对半挥发性有机物测定的影响。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0.01 mg/kg~0.04 mg/kg。土壤样品加标回收率为72.4%~954%,4次测定结果的RSD为2.1%~6.0%。将该方法应用于测定某重点行业企业用地周边土壤,除苯并(a)芘外其余8种半挥发性有机物均为未检出。  相似文献   

8.
采用二氯甲烷萃取水样,气相色谱-串联质谱法同时测定水中有机磷农药和甲萘威。试验表明:方法在20.0μg/L ~1000μg/L范围内,各目标化合物线性良好;方法检出限为0.004μg/L~0.01μg/L;对实际水样进行3个质量浓度水平的加标回收试验,回收率在71.8%~94.5%之间,RSD为3.7%~8.5%,满足水中痕量有机磷农药和甲萘威的测定要求。  相似文献   

9.
气相色谱法测定土壤和沉积物中12种有机磷农药   总被引:1,自引:0,他引:1  
建立了索氏提取-固相萃取(SPE)小柱净化-GC-NPD测定土壤和沉积物中的12种有机磷农药的方法。用正己烷-丙酮(9:1)进行索氏提取,SPE硅胶小柱净化,15 mL乙酸乙酯洗脱。适用于土壤和沉积物的干样和湿样中12种有机磷农药的测定,取样量为10 g时,方法检出限为0.304~1.469 μg/kg,样品加标平均回收率为67.10%~109.8%,相对标准偏差为3.39%~14.7%。  相似文献   

10.
采用DMA-80型直接测汞仪测定煤中汞含量,样品经过筛(100目)预处理,干燥温度和时间分别为200 ℃和30 s,分解温度和时间分别为650 ℃和90 s,基体元素对测定无明显干扰。方法在高质量浓度(0.200 mg/L~10.0 mg/L)和低质量浓度(0.400 μg/L~200 μg/L)范围内均线性良好,对0.100 g煤质样品的最低检出限为0.4 μg/kg,平行测定的RSD<5%,加标回收率>97%,与原子荧光法的测定结果相一致。  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.
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   

17.
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   

18.
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   

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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