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1.
研究了1,2,4,5-四氯苯在C18膜/水相之间的分配规律。1,2,4,5-四氯苯在:25℃,80r/min条件下恒温震荡96h可达分配平衡,温度和盐度对1,2,4,5-四氯苯C18膜/水的分配过程影响很小,1,2,4,5-四氯苯C18膜/水分配平衡时间受溶液体积和容器容积的影响,但不受溶液中C18膜膜量的影响,推测脂溶性小于或接近1,2,4,5-四氯苯的有机污染物在恒温震荡条件下C18膜与水之间的分配96h可达到平衡。  相似文献   

2.
通过两年多的试验,所有试验数据均与国家环保局编审的《空气和废气监测分析方法》中规定的24个实验室的二氧化硫标准曲线斜率、截距相符合,试验结果表明,用四氯汞钾吸收-盐酸副玫瑰苯胺分光光度法测定空气中二氧化硫的关键试剂--四氯汞钾吸收液,在密闭和冷藏的条件下,至少可保存2年。  相似文献   

3.
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   

4.
液相色谱-质谱法测定土壤中四溴双酚A和六溴环十二烷   总被引:1,自引:1,他引:0  
文章建立了液相色谱-串联四级杆质谱仪同时测定土壤中四溴双酚A及3种六溴环十二烷同分异构体的分析方法。土壤样品经快速溶剂仪萃取,全自动凝胶净化系统净化后,使用液相色谱-串联四级杆质谱仪,负离子电喷雾多反应监测模式监测,内标法定量分析。结果表明,土壤中四溴双酚A、α-六溴环十二烷、β-六溴环十二烷和γ-六溴环十二烷的检出限为0.1~1.2 pg/g,加标回收率为81.8%~113%,相对标准偏差小于10%。该方法分析时间短,灵敏度高,操作简单,对电子固废拆解场地中的179个土壤样品进行分析,取得满意结果。  相似文献   

5.
预浓缩系统与PFPD检测器联用测定环境空气中四氢噻吩   总被引:1,自引:1,他引:1  
采用预浓缩系统与GC-PFPD联用,建立了环境空气中四氢噻吩的分析方法,该法用苏玛罐或Tedlar袋采集空气样品在预浓缩系统中经液氮于-160℃冷冻浓缩后,用GS-GASPRO专用毛细管色谱柱及GC-PFPD检测。四氢噻吩的最低检出限为2·0μg/m3。经6次的重复测定,其相对标准偏差小于5·0%。该方法已用于环境空气中四氢噻吩的测定,取得了令人满意的结果。  相似文献   

6.
催化动力学光度法测定痕量铜(Ⅱ)   总被引:3,自引:0,他引:3  
研究了在稀硫酸介质中,用α,α‘-联吡啶作活化剂,痕量铜催化高碘酸钾氧化茂红T的褪色反应及动力学条件,建立了催化动力学光度法测定痕量铜的方法。检测限为0.41μg/LCu,线性范围为0-0.8μg/25mLCu。方法操作简单,灵敏度高,准确性好,可用于水质及人发中痕量铜的测定,结果满意。  相似文献   

7.
以焦作市韩王矿沉陷区林地土壤为研究对象,测定不同沉陷部位和不同深度土壤中8项肥力指标,基于隶属度函数和灰色关联度分析法,对沉陷区土壤肥力质量进行评价。结果表明:沉陷区林地土壤硝氮、全氮、速效钾、全钾和有机质含量在不同层位之间存在显著性差异(P<0.05),上层(0 cm~20 cm)硝氮、速效钾和有机质含量显著高于下层(20 cm~40 cm);土壤肥力质量在空间上呈现出明显的变化特征,坡中处最高,坡底处最低;速效磷是影响沉陷区土壤肥力质量提升的限制性因子。  相似文献   

8.
新疆和田地区土壤中天然放射性核素含量水平的调查研究   总被引:1,自引:0,他引:1  
和田地区土壤中天然放射性核素铀-238、钍-232、镭-226和钾-40按面积加权的均值(Bq·kg-1)依次是37.52±8.73、40.15±5.30、30.01±4.60和531.14±40.77,属正常本底辐射水平.铀镭平衡状况富铀。  相似文献   

9.
建立了一次性餐具中砷的氢化物发生-原子荧光测定方法,在选定的试验条件下,荧光强度与砷质量浓度在0μg/L-180μg/L范围内呈线性关系,相关系数0.999 3,溶液检测限0.5μg/L,回收率96%-101%。  相似文献   

10.
在酸雨研究领域,人们普遍是对降雨或降雪等湿沉积过程进行研究.近年来,干沉积也引起了大家的关注,但尚未建立成熟的方法.文章介绍了利用四段滤膜法进行干沉积监测的方法,作为日本全国公害研究协会的合作项目在日本神户和丰冈市进行了实际测量和评估.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 ± 0.804 Bq/kg) and 238U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.  相似文献   

17.
Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms, including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized. However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury, and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese). The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts. In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year. Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play a role in a subsistence diets.  相似文献   

18.
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.
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.
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   

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