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1.
污染土壤中六价铬的测定   总被引:6,自引:1,他引:5       下载免费PDF全文
通过加入碱性消解液、MgCl2和磷酸缓冲溶液,建立了污染土壤中六价铬的分光光度测定法.方法在0 mg/L~0.200 mg/L范围内线性良好,检出限为0.16 mg/kg(以2.5 g样品计),土壤样品测定的RSD为4.6%,加标回收率为92.3%~107%.  相似文献   

2.
超声波萃取-红外分光光度法测定土壤中石油类   总被引:1,自引:0,他引:1  
采用超声波萃取-红外分光光度法测定土壤中石油类,并对超声波机的功率、水浴温度和萃取时间进行优化.试验表明:方法在0mg/L~80.0mg/L范围内线性良好,相关系数r为0.9997;方法检出限为6.00μg/L,当取土壤样品10.0g时,方法检出限为0.03mg/kg;空白土壤的加标回收率为97.4% ~103%;测定实际土壤样品的RSD为3.0% ~3.9%.通过比较超声波萃取、四氯化碳热浸法和快速溶剂萃取法的前处理效果,显示出超声波萃取法的优越性.  相似文献   

3.
采用气相色谱法测定油田区土壤中C_(10)~C_(40)的石油烃,通过优化加速溶剂萃取的条件,使方法在62 mg/L~3 100 mg/L范围内线性良好,方法检出限为4.8 mg/kg。用该方法测定石油区短期、中期、长期油井污染土壤样品,5次测定结果的RSD为1.3%~5.2%,加标回收率为84.8%~98.5%,有证标准样品测定结果在可信区间内。  相似文献   

4.
高效液相色谱法测定土壤中阿维菌素残留   总被引:1,自引:0,他引:1       下载免费PDF全文
采用高效液相色谱法紫外检测器测定土壤中的阿维菌素残留,选择丙酮为提取剂、二氯甲烷为萃取剂,优化了色谱条件.方法在0 mg/L~12.1 mg/L范围内线性良好,检出限为0.014 mg/kg,空白土壤加标样品平行测定的RSD≤6.5%,回收率为78.6%~83.1%,残留试验表明阿维菌素在土壤中消解速率较快.  相似文献   

5.
气相色谱法测定柑橘和土壤中螺螨酯残留   总被引:1,自引:0,他引:1  
以丙酮为提取剂,二氯甲烷为萃取剂,采用弗罗里硅土柱净化,气相色谱-电子捕获检测器测定柑橘和土壤中的螺螨酯残留,优化了样品前处理条件。方法在0.141μg/L~5.65 mg/L范围内线性良好,最低检出限为0.003 5 mg/kg,空白样品在0.050 mg/kg、0.500 mg/kg、1.00 mg/kg 3个添加水平上的平均回收率为82.2%~110%,平行测定的RSD为2.6%~9.8%。  相似文献   

6.
采用丙酮-正己烷混合溶液(体积比为1∶1)提取石油污染土壤样品中10种典型多环芳烃,用GC-MS/MS法测定。通过优化前处理和测定条件,使方法在0.100 mg/L~10.0 mg/L范围内线性良好,方法检出限为5.00μg/kg~15.8μg/kg。土壤样品加标回收试验6次测定结果的RSD为0.1%~16.6%,加标回收率为43.1%~109%。将该方法用于测定湖南某石化项目周边的实际土壤,结果表明该地区不同点位土壤中多环芳烃测定值为未检出~300μg/kg,在国家标准规定的范围内。  相似文献   

7.
采用顶空气相色谱法快速测定土壤中苯、苯胺和硝基苯,优化了试验条件.方法在0 mg/L~100 mg/L范围内线性良好,苯、苯胺、硝基苯的检出限分别为0.012 mg/kg、0.22 mg/kg、0.083 mg/kg,实际土样测定的RSD≤1.4%,加标回收率为94.0%~102%.  相似文献   

8.
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   

9.
采用微波消解处理鱼肉样品,用电感耦合等离子体质谱法测定样品中砷和汞。通过试验优化微波消解参数、酸体系及赶酸温度,用在线加入内标方法消除基体干扰及仪器漂移对测定的影响。方法在0μg/L~40. 0μg/L范围内线性良好,砷和汞的方法检出限分别为0. 002 mg/kg和0. 001 mg/kg,实际样品6次测定结果的RSD为5. 4%~15. 6%,加标回收率为90. 0%~110%。将该方法用于测定芹菜和扇贝标准物质,测定值在标准值不确定度范围内。  相似文献   

10.
采用振荡吸附处理土壤样品,用微库仑法和离子色谱法分别测定土壤中的可吸附有机卤素(AOX)。通过优化样品前处理条件以提高AOX的提取效率,上述两种方法检出限分别为15.3 mg/kg和16.3 mg/kg, 4-氯苯酚作为标准物质的加标回收率分别为92.2%~95.0%和77.7%~80.2%。两种方法测定实际土壤样品中AOX,6次测定结果的RSD为5.4%~19.2%。GSS系列标准土壤试验结果表明,振荡吸附处理样品,用微库仑法和离子色谱法在测定样品中AOX时测定结果区别不大,土壤中AOX含量与卤素含量无直接关系。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
18.
The present study demonstrates comparison of Cr accumulatingpotential by the plants of Najas indica Cham. (submerged),Vallisneria spiralis L. (rooted submerged) and Alternanthera sessilis R. Br. (rooted emergent) under repeatedmetal exposure and its effect on chlorophyll and protein concentrations. These plants were treated with different concentrations of Cr under repeated exposure in controlled laboratory conditions to assess the maximum metal accumulationpotential. The plants of V. spiralis accumulated significantly high amount of Cr under laboratory conditions incomparison to N. indica and A. sessilis. The maximumaccumulation of 1378, 458 and 201 g g-1 dw Cr was found in the leaves of V. spiralis, N. indica and A. sessilis, respectively at 8 mg L-1 after 9 day of Cr exposure. These plants have shown a decrease in chlorophyll andprotein concentrations with increase in Cr concentrations. In view of high accumulation of Cr in V. spiralis, the plantswere treated with different concentrations of tannery effluent collected from Common Effluent Treatment Plant, Unnao (UP). Theplants of V. spiralis treated with 100% tannery wastewatershowed the maximum accumulation (57.5 g g-1 dw) of Cr in the roots after 10 days of exposure. The plants were foundeffective in removing Cr from solution and tannery effluent.  相似文献   

19.
一起河流砷污染事故的处置与监测分析   总被引:2,自引:1,他引:1  
介绍了大沙河砷污染事故的处置和监测分析。多介质排查监测摸清了污染的范围和程度,为治理工作提供了科学依据,污染治理措施有效控制了污染的扩散;监测数据表明,治理措施将水中砷污染物沉降至河床使污染水质达标排放。吸附了大量砷化合物的底泥被清理并进一步处置,多介质跟踪监测应持续进行直至不存在潜在危害。  相似文献   

20.
日本核泄漏事故引发的核危机为人类安全和平地利用核能又一次敲响了警钟.核事故应急工作作为减小核电站危害环境和公众安全的最后屏障,将起到重要的作用,必须做好相关的准备和响应工作.核应急辐射环境监测工作是核应急工作的重要组成部分,在对核应急辐射环境监测进行准备和响应时主要遵循实用性、适用性和适度性并兼顾常规和应急监测的“平战...  相似文献   

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