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1.
吹扫捕集-气相色谱-质谱法测定水中痕量丁基黄原酸   总被引:1,自引:1,他引:0  
建立了吹扫捕集-气相色谱-质谱联用测定水中丁基黄原酸的方法.丁基黄原酸在酸性条件下分解成易挥发的二硫化碳,经吹扫捕集富集后用气相色谱分离质谱定量测定.与传统的分光光度法相比,更简便快捷,在0.25~10.0μg/L范围内线性良好,准确度高,添加回收率为98.3%~105%,精密度好,相对标准偏差为5.92% ~ 10.7%,方法检出限为0.07μg/L.与顶空法相比,灵敏度更高.  相似文献   

2.
采用吹扫捕集气相色谱法测定地表水中六氯丁二烯,具有定量准确、操作简便等特点。该方法灵敏度高,当水样体积为5mL时,检测限可达0.2μg/L,适合地表水中低浓度六氯丁二烯的测定。  相似文献   

3.
国青 《干旱环境监测》2011,25(2):115-119
对吹扫捕集气相色谱法分析水中苯系物(苯、甲苯、乙苯、对、间-二甲苯、邻-二甲苯、异丙苯)的方法进行了研究,并讨论了吹扫捕集测定的优化条件,探讨了影响测定的各因素应注意的问题,并对实际水样进行了方法对比实验.结果表明,该方法操作简单、灵敏度高、重复性好,适用于饮用水、地表水、污水的测定.  相似文献   

4.
从仪器精密度、方法检出限、准确度等角度对吹扫捕集浓缩仪Stratum PTC与Eclipse 4660的性能进行比较。结果表明,大部分分析物用Stratum PTC的方法检出限略高于Eclipse 4660,但精密度比Eclipse 4660稍差;Eclipse 4660用于分析极性的、水溶性物质的效果比Stratum PTC好,回收率更高。两种吹扫捕集仪的测试结果均满足《土壤和沉积物挥发性有机物的测定吹扫捕集/气相色谱-质谱法》(HJ 605-2011)标准方法的指标要求。  相似文献   

5.
对饮用水源水中丙烯醛的气相色谱标准测定方法作了改进,由直接进样改为吹扫捕集进样,由极性色谱柱改为中等极性色谱柱.方法在0.010 mg/L~0.100 mg/L范围内线性良好,最低检出限和检测下限分别为0.000 5 mg/L和0.002 mg/L,水样平行测定的RSD为2.8%~5.2%,平均加标回收率为90.0%~...  相似文献   

6.
吹扫捕集-气相色谱法测定水中挥发性卤代烃和氯苯   总被引:10,自引:4,他引:10       下载免费PDF全文
建立了吹扫捕集-大口径毛细管柱气相色谱法同时测定饮用水和地表水中5种挥发性卤代烃和4种氯苯类污染物的方法,可不经有机溶剂萃取和浓缩,减少了沾污和损失,具有灵敏度高,受干扰因素少,定量准确,操作简便等特点。进样量为5mL时,检测限可达ng/L级,适合饮用水及地表水中低含量卤代烃和氯苯类污染物的测定。  相似文献   

7.
静态顶空进样气相色谱法测定水中CS2的研究   总被引:2,自引:0,他引:2  
采用气相色谱法静态顶空进样,极性柱分离,ECD检测器检测,对CS2的测定进行了全面的实验.实验表明,本方法简单、快速,并且具有精密度好、准确度高和检出限低的特点,完全能够满足快速分析水中CS2的要求.  相似文献   

8.
吹扫-捕集气相色谱法测定水中挥发性卤代烃   总被引:9,自引:0,他引:9  
研究建立了利用吹扫—捕集气相色谱法测定水中挥发性卤代烃的分析方法,并利用该方法对不同水体中的该类物质进行了测定。当水样体积为5ml时,9种卤代烃的最低检出浓度为2.86×10-3~9.77×10-2ppb。  相似文献   

9.
对测定水中乙醛和丙烯醛的3种方法——2,4-二硝基苯肼衍生化法、顶空气相色谱法和吹扫捕集一气相色谱质谱法进行概述和总结,并对各方法的试验条件、方法原理、测定影响因素以及效能验证等分析、比对,突出表现各自的优势和特点。用3种方法同时测定实际水样,结果无显著差异,精密度、准确度满足监测要求。  相似文献   

10.
吹扫捕集法自1974年提出以来被广泛的用于地表水、地下水、饮用水和废水中挥发性、半挥发性有机物的检测。吹扫捕集/气相色谱联机有很好的方法检测限,可以检测出浓度为0.1μg/L的挥发性有机物,但水样中这类有机物的含量通常是痕量级别,要做到准确测量,需要仪器检测时的条件处于最佳,现对吹扫捕集装置的性能、吹扫时间、解吸时间和解吸温度等条件进行选择。  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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