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1.
针对太原市空气臭氧污染较为严重的问题,开展臭氧主要前体物醛酮化合物质量浓度及其变化规律研究.利用2,4-二硝基苯肼固相吸附/高效液相色谱方法,通过对太原市2019年冬季和夏季大气的醛酮化合物进行分析,发现太原市冬季总醛酮化合物的平均质量浓度为13μg/m3,低于夏季的27μg/m3.其中甲醛、乙醛和丙酮质量浓度最高,且...  相似文献   

2.
在企业污染源现场实现污染物排放浓度水平的快速判定和超标风险筛查,对生态环境管理部门提高执法效率、企业提高环境管理水平意义重大。铅是一种对人体危害极大的有毒重金属,目前缺少含铅废气中铅及其化合物的便携式直读检测设备和检测方法。探索性地将X射线荧光光谱(XRF)法应用于铅蓄电池企业含铅废气中铅及其化合物的便携式快速、直读检测。研究结果表明,基于XRF的面密度法适用于铅蓄电池企业含铅废气处理设施后铅及其化合物的快速、直读检测,相对国标方法具有快速、直读、对样品无损、便于复测等特点,可用于铅及其化合物排放浓度水平的快速判定和超标风险筛查。  相似文献   

3.
根据国内外研究报道,系统地总结了计算毒理学和化合物环境行为模拟在环境科学领域的研究进展,包括二者的概念、理论、研究方法以及在环境研究中的应用;分析了计算毒理学和化合物环境行为模拟在发展中所面临的挑战,并提出对策;展望了计算毒理学和化合物环境行为模拟在环境研究中的发展前景。  相似文献   

4.
由于目前尚有大量的化学物质,对人体和生物的毒性未被认识,况且工业排放的废渣往往多为复合化合物,常规理化方法虽然能进行部分元素及其化合物的定量测定,但往往只能进行单项毒物含量测定和瞬间测定,不能检验出毒物联合作用的综合毒性及其长期积累性.因此本研究重视应用生物检测手段,旨在通过大型溞斑马鱼的急性毒性试验、发生细菌的生物毒性测试以及紫露草雄蕊毛突变检测等四个指标,利用生物对环境毒物具有的指示性、敏感性、蓄积性、遗  相似文献   

5.
环境污染物可以通过饮水、食物、空气以及接触等途径进入人体,在体内畜积并引起对人体健康的潜在危害.为评价这种危害的程度及提供制订有关环境保护对策的依据,我国北京市和江苏省,选择试验点参加了世界卫生组织(WHO)和联合国环境规划署(UNEP)组织的人体暴评价点规划(HEALSPROGRAMME).根据规划要求,于1990年在无锡市进行人体有机氯化合物暴露评价点规划(HEAL PROGRAMME).根据规划要求,于1990年在无锡市进行人体有机氯化合物暴露分析及其体负荷的研究.本次研究目标为:  相似文献   

6.
析因试验设计在环境污染物联合毒性研究中的应用   总被引:11,自引:0,他引:11  
结合当前化学污染物联合毒性评价方法及析因试验应用现状,从试验设汁方法及统计学角度,论证析因试验在研究环境化学污染物联合毒性,特别是在2种化合物联合毒性研究中应用的优势及其可行性。  相似文献   

7.
探究复杂环境介质中有机污染物分析检测新方法,建立复杂环境介质中可疑和非目标化合物的快速筛选及确证方案,已成为环境科学领域的研究热点。高分辨质谱仪(HR-MS)具有质量范围宽、扫描速度快、灵敏度高等优点,使其在环境科学领域得到广泛应用。综述了混合高分辨率质谱(Q-TOF/Q Orbitrap)等HR MS技术的特点和工作原理,基于目标化合物分析、可疑化合物分析以及非目标化合物分析这3类研究策略,阐述了HR-MS在环境研究、药品监管及生物代谢物研究等领域的应用现状,进而分析了现阶段HR MS在环境科学领域中的应用局限性和发展前景。  相似文献   

8.
环境中邻苯二甲酸酯类物质的污染现状与监测方法   总被引:8,自引:0,他引:8  
综述了环境中邻苯二甲酸酯类物质(PAEs)的理化性质、环境行为及在多介质环境中的污染概况,系统介绍了不同介质中PAEs的前处理与分析方法,总结了我国开展PAEs环境监测存在的问题及其意义.  相似文献   

9.
陈姣  王冠 《中国环境监测》2016,32(3):99-104
随着环境问题日渐突出,地表灰尘重金属污染日益成为研究热点。单纯采用化学方法监测重金属污染具有一定局限性,环境磁学方法以其简便、快捷、经济且无害化的特点在城市重金属污染研究中广为应用。通过文献调研,综述环境磁学在城市地表灰尘重金属污染研究中的应用与研究进展,阐明重金属的主要来源,简述环境磁学的诸多参数,分析磁学参数与重金属的关系,并通过对比不同的磁学分析方法,探讨环境磁学方法在城市地表灰尘重金属污染研究中存在的问题及其发展趋势。  相似文献   

10.
1 汞样的保护汞及其化合物之所以难以测定,不仅因为汞在环境中的存在量甚微,而且由于本身的性质不稳定,易受共存的组分和微生物的作用,以及离子价态,容器的吸附和环境气温等种种影响.因此,对于汞样的保存,试剂提纯,样品予处理和测定方法一直是测定汞的较大的难题.本文想针对这些难题作进一步讨论,以期有助于汞的分析.  相似文献   

11.
The introduction of catalytic converters has led to a new environmental problem since catalysts emit platinum group elements (PGEs) which are among the least distributed elements in nature. Along with PGEs the vehicle exhaust catalysts contain also a number of stabilizers, commonly oxides of rare earth elements and alkaline earth elements such as Ce, La and Zr. Since vehicular emission of these elements has received little attention so far this work attempts to offer insight into their distribution and fate in the environment by measuring their speciation in road dust samples collected along several highways in Germany and a city centre (Saarbrücken). Speciation of the elements (fractionation into associated mineralogical phases) was carried out via a conventional sequential extraction protocol and the complexing abilities of humic substances in the organic matter were investigated by selective extraction methods in combination with size segregation. For evaluation purposes soil samples spiked with catalytic converter material were analyzed, showing a much lower fraction of Ce, La and Zr mobilized in comparison to the road dust samples. It was found that the elements were effectively bound to humic substances in road dust with a preference for complexation with low molecular weight compounds (<1600 Da).  相似文献   

12.
Platinum, palladium, rhodium, iridium and osmium were found to be enriched relative to their expected natural concentrations in peat samples from Thoreau's Bog, an ombrotrophic peat bog in Concord, Massachusetts. The source of osmium into the bog was determined from its isotopic composition (187Os/188Os). Osmium is composed of 4% lithogenic osmium from atmospheric soil dust, 41% of anthropogenic osmium and 55% of osmium from a non-lithogenic, non anthropogenic source, with rain being a likely candidate for the latter. Significant anthropogenic and rain contributions are also expected for iridium. In contrast, platinum, palladium and rhodium are almost exclusively anthropogenic. The larger enrichments of platinum, palladium and rhodium indicate that automobile catalysts are the source of platinum group elements to Thoreau's bog. The bog is located approximately 300 m from a major road and, therefore, the occurrence of platinum elements is evidence for regional dispersion of these metals. The absence of a clear trend following the introduction of catalysts indicates that platinum group elements are not quantitatively conserved in peat with downward leaching and plants playing an important role in the accumulation of platinum group elements.  相似文献   

13.
In order to control the quality of platinum, palladium and rhodium determinations in road dust, the Standards, Measurements and Testing Programme (formerly BCR) of the European Commission has started a project, the final aim of which is to certify a road dust reference material for its contents of platinum group elements. The first part of this project consisted of an interlaboratory study, which aimed to test the feasibility of the preparation of a candidate road dust reference material and to detect and remove most of the pitfalls observed in platinum, palladium and rhodium determinations. This paper presents the main results of this interlaboratory study carried out prior to the certification campaign. The concordance of the data obtained by the participating laboratories for the three elements was considered to reflect the state-of-the-art and was encouraging enough to decide on the organization of a certification campaign to be conducted during the year 2000. The progress made with respect to the analytical state-of-the-art for these elements will be of great benefit to the quality of measurements carried out in environmental monitoring in this particular field.  相似文献   

14.
The paper presents the first report on the application of a lead film electrode for the determination of ultratrace concentrations of platinum. The procedure is based on preconcentration of the Pt(IV)-formaldehyde complexes at an in situ plated lead film electrode held at ?0.9 V (vs. Ag/AgCl), followed by a negatively sweeping differential pulse voltammetric scan. The composition of the supporting electrolyte, the influence of accumulation potential and time on the sensitivity of platinum responses are discussed. The detection limit of Pt(IV) with the accumulation time of 60 was equal to 9.2?×?10?12 mol L?1. The application of this method was tested by recovery of Pt(IV) from spiked environmental water samples.  相似文献   

15.
Platinum, gold and calcium concentrations of 20 samples of airborne dust collected at two sampling sites between 1995 and 1997 in the city of Copenhagen, which suffers from heavy traffic, were determined by instrumental neutron activation analysis (INAA). INAA of platinum using the 199Au daughter of 199Pt was performed. Two interferences on the INAA of platinum were removed by calculations. The spectral interference on 199Au from the 47Sc daughter of 47Ca was removed by separating the 157-161 keV doublet peak into its components by calculating the counts due to 47Sc from the counts of the parent 47Ca. The contribution of 197Au to 199Au by two neutron absorption was corrected for using the ratio 198Au/199Au in a pure Au standard. From the INAA results, high platinum concentrations are present in air in the range 0.25-2.74 ng m-3 and gold concentrations in the range 0.10-1.96 ng m-3.  相似文献   

16.
4-[N,N-(Diethyl)amino] benzaldehyde thiosemicarbazone (DEABT) is proposed as an analytical reagent for the spectrophotometric determination of platinum(IV). The DEABT forms 1:2 yellow complex with Pt(IV), which is sparingly soluble in water and completely soluble in water–ethanol–DMF medium. The Pt(IV)–DEABT complex shows maximum absorbance at 405 nm. Beer’s law is valid up to 7.80 μg cm???3, and optimum concentration range for the determination of platinum(IV) is 0.48–7.02 μg cm???3. The molar absorptivity and Sandell’s sensitivity of the method are found to be 1.755 × 104 dm3 mol???1 cm???1 and 0.0012 μg cm???2, respectively. The relative error and coefficient of variation (n?=?6) for the method does not exceed ±0.43% and 0.35%, respectively. Since the method tolerates a number of metal ions commonly associated with platinum, it can be employed for the determination of platinum in environmental samples, pharmaceutical samples, alloys, catalysts, and complexes. The method is rapid as the Pt(IV)–DEABT complex is soluble in water–ethanol–DMF medium and not requiring any time consuming extraction method for the complex.  相似文献   

17.
HPLC and HPLC-MS are the fastest and most accurate techniques for analysis of organic phosphorus pesticide (OPP) at the present time. Using these techniques, 14 strains of methamidopho (MAP) degrading-bacteria from the area contaminated with MAP have been identified. The results from HPLC and HPLC-MS analyses showed that the highest degradation rate was 73% after 7 days. In order to determine what metabolites will be formed after degradation, a key issue that has been neglected for a long time, we used (31P) NMR to track the degradation process. The results showed that different strains produced different metabolites. Ten strains were divided into three groups (groups A, B and C) by their metabolic profiling. Strains in group A degraded MAP into phosphor acid by breaking down all P–N, P–O and P–S bonds in 7 days. Strains in groups B and C had only broken down partially P–N and P–S bonds at the same time. Therefore, the bacterial strains in group A had a greater application potential than the other two groups. In addition, most metal phosphates are unsolvable in water. The analysis of X-ray showed, that the phosphate radicals generated by bacterial degradation induce crystallogenesis of heavy metal salts in water phase and also cause the chemical sedimentation of their crystals. Furthermore, these crystals are hydrogen phosphates. The results suggested that the MAP-degrading bacteria could be used for cleaning up not only the organic phosphorous pesticide contamination but also the phosphorous and heavy metal contamination in water environment simultaneously.  相似文献   

18.
Since the introduction of catalytic converters for the control of vehicle emission, a controversial discussion has begun on platinum emission and its eventual consequences for the environment. This brief overview covers the main aspects of anthropogenic emission of platinum and its bioavailability. Modern analytical methods for Pt determination in different environmental samples are also presented.  相似文献   

19.
Metals have been central to the development of human civilisation from the Bronze Age to modern times, although in the past, metal mining and smelting have been the cause of serious environmental pollution with the potential to harm human health. Despite problems from artisanal mining in some developing countries, modern mining to Western standards now uses the best available mining technology combined with environmental monitoring, mitigation and remediation measures to limit emissions to the environment. This paper develops risk screening and prioritisation methods previously used for contaminated land on military and civilian sites and engineering systems for the analysis and prioritisation of chemical risks from modern metal mining operations. It uses hierarchical holographic modelling and multi-criteria decision making to analyse and prioritise the risks from potentially hazardous inorganic chemical substances released by mining operations. A case study of an active platinum group metals mine in South Africa is used to demonstrate the potential of the method. This risk-based methodology for identifying, filtering and ranking mining-related environmental and human health risks can be used to identify exposure media of greatest concern to inform risk management. It also provides a practical decision-making tool for mine acquisition and helps to communicate risk to all members of mining operation teams.  相似文献   

20.
The temporal trends (1974-1995) of 11 organochlorine contaminants in herring gull eggs from 13 colonies throughout the Great Lakes were statistically analyzed using two regression methods on logarithmically transformed data. Change point analysis was used to determine if there had been significant year to year fluctuations in contaminant levels and/or changes in long-term trends. Short-term regressions were conducted on 6 major compounds for two time periods (early 1990s and early 1980s) to compare the rates of decline. Overall, change point analyses indicated that for most of the comparisons (75%) there had been significant year to year fluctuations in contaminant levels. They also indicated that for most of the comparisons (67%) the rate of decline after the change point was as fast as or faster than before the change point, this pattern was most common for dieldrin and heptachlor epoxide at certain locations. In 19% of the comparisons the rates of decline had slowed or stabilized, this was most common for PCB and pentachlorobenzene. In 14% of the comparisons there were no significant temporal trends, this was most common for photomirex and mirex. Results for short-term regression showed that out of 78 comparisons for each time period, 5 (6%) were declining significantly in the early 1990s and 11 (14%) were declining significantly in the early 1980s. Both types of regression indicated that, for most of the herring gull egg contaminant database, recent logarithmic rates of decline were similar to those seen previously in the sampling period. For PCB 1254:1260, a group of compounds of particular toxicological importance, change point analyses indicated that the logarithmic rates of decline in herring gull eggs from western Lake Ontario were slower from 1987-1995 than they were from 1974-1986. At both Lake Superior colonies and the Niagara River colony PCB 1254:1260 concentrations ceased to decline in the mid-1980s. At the colony in Green Bay, Lake Michigan, PCB 1254:1260 levels have shown no significant temporal trend since 1976. At the remaining 8 colonies, PCB 1254:1260 levels continue a logarithmic decline in recent years at the same rate as or faster than previously.  相似文献   

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