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1.
用Waters Oasis MCX固相萃取小柱富集水中的苯胺和联苯胺,以2%氨水-甲醇混合溶液为洗脱液,采用高效液相色谱法DAD检测器在285 nm波长下测定。苯胺和联苯胺分别在0 mg/L~100 mg/L和0 mg/L~10.0 mg/L范围内线性良好,检出限分别为0.3 μg/L和0.1 μg/L,饮用水加标平行测定6次的RSD分别为0.9%和0.3%,回收率分别为98.3%~99.1%和97.6%~102%。 相似文献
2.
采用液液萃取、气相色谱氮磷检测器同时测定水中吡虫啉和氟虫腈,以二氯甲烷为提取溶剂,考察了提取酸碱条件的影响.吡虫啉和氟虫腈分别在1.00 mg/L ~ 20.0 mg/L和0.500 mg/L-10.0 mg/L范围内线性良好,检出限分别为0.018 mg/L和0.004 mg/L(按取样体积200 mL,定容体积5 ... 相似文献
3.
在酸性条件下,水样中的六价铬能够和显色剂二苯碳酰二肼反应生成紫红色络合物,该络合物溶液用自制的数字图像比色装置测定颜色值实现六价铬的现场快速检测。该方法在0.05 mg/L~1.00 mg/L范围内线性良好,方法检出限为0.02 mg/L,标准溶液10次测定结果的RSD为1.6%~7.9%,实际水样加标回收率为94.7%~102%。用该方法与国标法同时测定实际水样,结果无显著差异。 相似文献
4.
采用离子色谱法测定水中钙、镁离子质量浓度,并以此计算水中总硬度。方法在0 mg/L~10.0 mg/L范围内线性良好,钙、镁离子的方法检出限分别为0.02 mg/L、0.003 mg/L。该方法用于测定标准混合溶液和有证标准物质,测定结果均满足质控要求。实际水样中钙、镁离子均检出,且测定结果的RSD为0.3%~1.4%,加标回收率为91.0%~103%。用该方法与国标法同时测定实际样品,结果无明显差异。 相似文献
5.
采用离子色谱法测定水中溴离子与碘离子,选择AS19阴离子交换分离柱、KOH淋洗液自动发生器、抑制型电导检测。溴离子与碘离子分别在14.8 μg/L~100 mg/L与30.4 μg/L~100 mg/L范围内线性良好,检出限分别为3.7 μg/L与7.6 μg/L,环境水样平行测定的RSD分别为0.2%~1.5%与0.3%~1.6%,两个质量浓度水平的加标回收率分别为91.8%~105%与89.5%~93.4%。 相似文献
6.
顶空毛细管气相色谱法同时测定水中丙酮甲醇乙腈 总被引:1,自引:0,他引:1
采用顶空毛细管气相色谱法同时测定水中丙酮、甲醇和乙腈,确定顶空平衡温度为95 ℃,平衡时间为30 min,氯化钠质量浓度为200 g/L。丙酮、甲醇和乙腈在0.500 mg/L~5.00 mg/L范围内线性良好,检出限分别为0.02 mg/L、0.10 mg/L和0.04 mg/L,标准溶液平行测定的RSD≤3.0%,两个质量浓度水平的空白加标回收率范围为90%~108%。苯系物对测定不产生影响,吡啶会影响甲醇的测定。 相似文献
7.
采用二氯甲烷萃取稻田水样品,土壤样品用丙酮-二氯甲烷(体积比为9∶1)混合溶液提取,二氯甲烷萃取,水稻植株样品用乙腈-二氯甲烷(体积比为9∶1)混合溶液直接萃取,用气相色谱法同时测定样品中稻瘟酰胺和咪鲜胺残留。该方法在0.012 2 mg/L~2.68 mg/L范围内线性良好,稻田土壤、田水、水稻植株中稻瘟酰胺的检出限分别为2.75μg/kg、1.83μg/L、3.80μg/kg,咪鲜胺的检出限分别为3.55μg/kg、2.66μg/L、5.62μg/kg。空白稻田土壤、稻田水和水稻植株样品3个浓度水平的加标回收率为80.3%~104%,RSD为3.0%~13.2%。 相似文献
8.
郭维超 《环境监测管理与技术》2015,27(5):52-54
采用顶空-气相色谱法测定地表水中松节油,并对顶空瓶的平衡温度、平衡时间,盐析效应和取样量等顶空条件进行优化,使方法在0.200 mg/L~4.00 mg/L范围内线性良好,方法检出限为0.037 mg/L。实际样品2个质量浓度水平的加标回收率为89.3%~108%,RSD分别为5.8%和4.8%。 相似文献
9.
采用乙酸乙酯提取水样中己烯雌酚残留,经BSTFA/TMCS衍生化后,用GC-MS/MS测定,通过优化试验条件,使该方法在0.05 mg/L~1.00 mg/L范围内线性良好,方法检出限为146 ng/L。实际水样2个质量浓度水平的加标回收率为90.8%和91.9%,5次测定结果的RSD分别为2.2%和2.1%。 相似文献
10.
采用冻干法-全量酸消解-火焰原子吸收光谱法测定畜禽粪便中铜和锌,优化了试验条件.铜和锌分别在0 mg/L~3.00 mg/L和0 mg/L~1.00 mg/L范围内线性良好,检出限分别为6 mg/kg和2 mg/kg(按取0.5 g试样消解定容至50 mL计算),粪便试样测定的RSD分别为1.3%和3.7%,加标回收率分别为104%和107%. 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.
Ellis A. M. Franssen Brigit A. M. Staatsen Erik Lebret 《Environmental Impact Assessment Review》2002,22(6)
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.
Clifford A. Hui John Y. Takekawa Sarah E. Warnock 《Environmental monitoring and assessment》2001,71(2):107-121
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.
Besser JM Brumbaugh WG May TW Schmitt CJ 《Environmental monitoring and assessment》2007,129(1-3):227-241
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
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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