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1.
采用动态顶空气相色谱FID法测定水中乙醛、丙酮、甲醇、丙烯醛、丙烯腈、乙腈、吡啶等7种极性水溶性有机物,通过优化动态顶空条件,使该方法在0.157mg/L~7.92mg!L之间线性良好。方法检出限在0.008mg/L~0.048mg/L之间,空白水样的加标回收率为103%~111%,RSD为5.4%~8.7%。用该方法测定某制药企业排口污水和地表水,只有污水中甲醇、乙腈、吡啶有响应值。  相似文献   

2.
利用顶空—气相色谱对水中乙醛、丙烯醛、丙烯腈和吡啶进行检测分析,优化了实验参数。该方法在0.1~5.0 mg/L范围线性关系良好,相关系数大于0.999 6,当取样量为10 ml时,方法检出限分别为0.03、0.02、0.01、0.02 mg/L。该方法用于空白加标和实际水样分析,加标回收率为75.5%~113%,相对标准偏差在2.7%~7.1%。本方法操作简单,选择性好,灵敏度、准确度高,可用于地表水、生活污水和工业污水中乙醛、丙烯醛、丙烯腈和吡啶的测定,效果满意。  相似文献   

3.
研究了吹扫捕集-气相色谱法同时测定水中乙醛、丙烯醛和甲醛的方法并优化了实验条件.实验结果表明,该方法操作简便,灵敏高效,目标化合物的检出限分别为0.037、0.012、0.0006mg/L,相对标准偏差在3.9% ~15.8%之间,实际水样的加标回收率在73.0% ~118%之间,能很好满足《地表水环境质量标准》中相关项目的要求.  相似文献   

4.
顶空气相色谱法测定水和废水中的4-甲基- 2-戊酮   总被引:3,自引:0,他引:3       下载免费PDF全文
采用液上顶空气相色谱法测定地表水和废水中的4-甲基-2-戊酮。以HP-5毛细管柱分离,氢火焰离子化检测器检测,取得较好的结果。方法检测限为0.06mg/L,相对标准偏差为5%,加标回收率在82%~117%之间。  相似文献   

5.
建立了固相萃取-毛细管气相色谱测定地表水中硝基苯类化合物的方法,优化了试验条件。方法线性良好,10种硝基苯类化合物的检出限为0.05μg/L~0.15μg/L,实际样品测定的RSD为1.7%~5.0%,平均加标回收率为80.8%~117%。  相似文献   

6.
采用碱性过硫酸钾消解水样,OnGuardⅡBa柱萃取、过滤,去除消解液中大量硫酸盐,离子色谱法测定地表水中总氮含量。试验表明,方法在0ms/L~20.0mg/L之间线性良好,相关系数r为0.9994,方法检出限为0.007mg/L。该方法与国标法同时测定标准物质,测定值均在定值范围内,6次平行测定结果的RSD分别为2.3%和1.8%,地表水样的加标回收率为95.7%~105%。实际水样的测定结果与国标法比对,无明显差异。  相似文献   

7.
采用二氯甲烷提取地表水,浓缩后经超高效液相色谱紫外-三重四级杆质谱检测器联用测定甲萘威。试验表明:紫外检测器测定甲萘威,在2.00μg/L~500μg/L范围内线性良好,相关系数为0.9992,检出限为0.500μg/L;三重四级杆质谱检测器测定甲萘威,在0.100μg/L~200μg/L范围内线性良好,相关系数为0.9990,检出限为0.009μg/L;实际水样3个浓度水平的加标回收率为92.4%~98.4%,RSD为2.5%~6.5%。该方法中双检测器联用测定地表水加标样品,使得定性定量更加准确。  相似文献   

8.
毛细管气相色谱法测定空气中三种醛类污染物   总被引:5,自引:0,他引:5  
报道了以酸性2,4-二硝基苯肼为吸收液采集空气中的甲醛、乙醛和丙烯醛,以气相色谱法分析形成的腙衍生物。方法的回收率在95% 以上,最低检测限为0.35~8.4ng,线性工作范围为2.1~509ng,可测定空气和废气中的醛类污染物。  相似文献   

9.
用正己烷一次同时萃取地表水中的百菌清、环氧七氯和有机氯农药,萃取液脱水后进气相色谱仪进行测定。当取样体积为500ml时,方法检出限为0.01~0.02μg,/L,标准曲线相关系数大于0.999,方法精密度的相对标准偏差为1.5%-4.0%,加标回收率为81.6%~109.6%。该方法用于实际样品测定,结果令人满意。  相似文献   

10.
采用直接进样一超高效液相色谱-三重四级杆串联质谱法,建立了对地表水中丙烯酰胺的分析方法。该方法不需要衍生化等前处理步骤。结果表明,丙烯酰胺含量在0.100~10.0μg/L范围内具有很好的线性相关性,实际水样加标回收率为80.0%-105%。该方法的检出限和测定下限分别为0.025μg/L和0.100μg/L,能够满足地表水环境质量标准中关于饮用水中丙烯酰胺最高安全浓度指南的要求,提高了引用水源丙烯酰胺的检测要求。  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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