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1.
液相色谱法测定土壤中苯并(a)芘   总被引:1,自引:0,他引:1  
用快速溶剂萃取法ASE300对土壤样品进行前处理,以配有荧光检测器的高效液相色谱仪分析土壤样品中苯并(a)芘的含量,该方法以乙腈、水梯度比例混合作为流动相,流速为1.0 ml/min;激发波长和发射波长分别为255 nm和420 nm;保留时间为27.58 min。样品的称样量为25 g时,测定检出限为8.28×10-5mg/kg,相对标准偏差(RSD)为1.0%~12%,回收率为60%~87%,以上指标均能满足环境中土壤样品的检测要求。  相似文献   

2.
采用加速溶剂萃取一高效液相色谱法荧光检测器测定环境空气中的苯并(a)芘,以乙腈/水为流动相,检测器激发波长为290nm,发射波长为430nm。方法线性良好,检出限为0.08μg/L,当采样体积为1080m。时,最低检测质量浓度为3×10^-7μg/m^3(标准状态下),实际样品加标回收率为87.2%~109%。与超声波萃取法相比,两种方法回收率相近,而加速溶剂萃取法乙腈用量更少。  相似文献   

3.
通过试验建立了煤化工厂烟气中苯并(a)芘的液相色谱监测分析方法.通过条件优化,用配有荧光检测器的高效液相色谱仪分析烟气样品中苯并(a)芘的含量,该方法以乙腈、水梯度比例混合作为流动相;流速为1.0 ml/min;激发波长为255nm、发射波长为420nm;保留时间为27.38 min,测定检出限为2×10-3μg/m3...  相似文献   

4.
新的大气污染综合排放标准对沥青及碳素制品生产和加工制定了沥青烟和苯并(a)芘的排放标准,然而空气和废气监测分析方法没有给出沥青烟气中苯并(a)芘的分析方法.为此,用色谱固定液滤筒及新设计的富集器等速采样,进行沥青烟苯并(a)芘的分析,为执行新的大气污染综合排放标准提供了实用技术.  相似文献   

5.
用玻璃纤维滤膜采集PM10 样品,测量苯并[a]芘浓度。结果表明,时间分布上该市大气中苯并[a]芘月均值浓度最大值出现在11月,最小值出现在7月,空间分布上,呈现工业区>商住区>风景区,浓度分布受降水及工业生产的影响明显。  相似文献   

6.
通过全国多家实验室的大量监测数据,研究分析了土壤中苯并[a]芘测定的精密度控制指标,并与EPA8270D进行了比较,旨在为环境监测工作提供质量控制依据和质量控制指标。研究表明,标准样品的室内相对标准偏差的质量控制范围≤28%,室内相对偏差的质量控制范围≤34%。  相似文献   

7.
本文以高压液相色谱仪作为样品分析手段,对C18键合相吸附剂富集饮用水中苯并(a)芘回收效率的影响因素逐一进行系统研究。实验结果显示,在优化的样品富集和样品分析条件下,该方法具有快速、安全、高效和低耗等优点,在绝对进样量0025~03mg之间,线性良好,方法最低检出限为05ng/L,同时准确度和精密度也得到很好地控制。另外,该方法在自来水及其源水的样品分析中获得了良好的结果。  相似文献   

8.
采用超声提取-高效液相色谱法测定玉米作物中苯并(a)芘,优化了试验条件。方法在0mg/L-100mg/L范围内线性良好,检出限为0.15mg/L,玉米样品测定的相对标准偏差为5.3%~10.0%,加标回收率〉86.9%。  相似文献   

9.
本文采用高效液相色谱-荧光检测器法,用反相C18柱,在乙腈:水(V/V)=90:10作为流动相,检测波长:λEx=265nm,λEm=410nm,流速为1.5mL/min的条件下对饮用水中苯并[a]芘进行了方法学考查,本方法对苯并[a]芘的线性相关系数等于0.9998,RSD为1.46%,平均回收率为93.1%,方法操作简便、准确可靠、灵敏度较高。  相似文献   

10.
采用液液萃取-超高效液相色谱仪接荧光检测器测定地表水中超痕量的苯并(a)芘,并对方法空白的干扰因素进行探讨。研究发现,该法的空白干扰主要来自于溶剂二氯甲烷,溶剂经蒸馏提纯后可消除干扰。以重新蒸馏提纯的二氯甲烷为提取剂,方法的检测限为0.05 ng/L,加标回收率为87.4%~132%,且空白测定值低于方法检出限,可满足地表水中超痕量苯并(a)芘检测的需求。  相似文献   

11.
Strategies to conserve biodiversity need to include the monitoring, modelling, adaptation and regulation of the composition of the atmosphere. Atmospheric issues include climate variability and extremes; climate change; stratospheric ozone depletion; acid deposition; photochemical pollution; suspended particulate matter; and hazardous air pollutants. Coarse filter and fine filter approaches have been used to understand the complexity of the interactions between the atmosphere and biodiversity. In the first approach, climate-based models, using GIS technology, helped create future biodiversity scenarios under a 2 × CO2 atmosphere. In the second approach, the SI/MAB forest biodiversity monitoring protocols helped calibrate the climate-forest biodiversity baseline and, as global diagnostics, helped identify where the biodiversity was in equilibrium with the present climate. Forest climate monitoring, an enhancing protocol, was used in a co-location approach to define the thermal buffering capacity of forest ecosystems and their ability to reduce and ameliorate global climate variability, extremes and change.  相似文献   

12.
天津市空气颗粒物中酞酸酯的分布特征   总被引:1,自引:1,他引:1  
采用气相色谱-质谱仪(GC-MS)对天津市空气颗粒物中15种酞酸酯(PAEs)夏季和冬季的浓度进行了分析测定,研究了酞酸酯污染水平的季节变化,不同季节酞酸酯的功能区差异,15种酞酸酯在颗粒物中的分布特征,以及DBP和DEHP在夏冬两季中的污染特点,分析了产生上述结果的原因,基本说明了天津市空气颗粒物中酞酸酯的污染状况和特点。  相似文献   

13.
Predicted atmospheric change, mainly climate change, will have profound effects on the biodiversity of Canadian forests. Predictions derived from forest models, responses of species and ecosystems related to modern ecological characteristics and paleoecological studies suggest large-scale, wide-ranging changes from the biome to physiological levels. Paleoecological analogues in B.C. and other parts of Canada reveal that major changes must be expected in forest composition, range, structure and ecological processes. In B.C., past warmer and drier climates supported a different forest pattern, including forest types with no modern analogue. This produced dramatically different disturbance regimes, specifically more fires, and affected tree growth rates. The relationship of forests with non-forest habitats, especially wetlands and grasslands was different suggesting implications for wildlife biodiversity. British Columbia's Forest Practices Code prescribes guidelines for biodiversity objectives but ignores the issue of atmospheric change. This omission may result from a lack of understanding of the profound potential effects of atmospheric change on forest biodiversity in the next harvest cycle and lack of mechanisms to assess impacts and develop management strategies for specific sites. An example of a simple paleoecological assessment method involving pollen ratios is proposed.  相似文献   

14.
Atmospheric Change and Biodiversity in the Arctic   总被引:2,自引:0,他引:2  
The Canadian Arctic is characterized by a high variation in landform types and there are complex interactions between land, water and the atmosphere which dramatically affect the distribution of biota. Biodiversity depends upon the intensity, predictability and scale of these interactions. Observations, as well as predictions of large-scale climate models which include ocean circulation, reveal an anomalous cooling of northeastern Canada in recent decades, in contrast to the overall significant increase in average annual temperature in the Northern Hemisphere. Predictions from models are necessary to forecast the change in the treeline in the 21st century which may lead to a major loss of tundra. The rate of change in vegetation in response to climate change is poorly understood. The treeline in central Canada, for example, is showing infilling with trees, and in some locations, northerly movement of the boundary. The presence of sea ice in Hudson Bay and other coastal areas is a major factor affecting interactions between the marine and terrestrial ecosystems. Loss of ice and therefore hunting of seals by polar bears will reduce bear and arctic fox populations within the region. In turn, this is likely to have significant effects on their herbivorous prey populations and forage plants. Further, the undersurface of sea ice is a major site for the growth of algae and marine invertebrates which in turn act as food for the marine food web. A rise in sea-level may flood coastal saltmarsh communities leading to changes in plant assemblages and a decline in foraging by geese and other consumers. The anomalous cooling in the eastern Arctic, primarily in late winter and early spring, has interrupted northern migration of breeding populations of geese and ducks and led to increased damage to vegetation in southern arctic saltmarshes as a result of foraging. It is likely that there has been a significant loss of invertebrates in those areas where the vegetation has been destroyed. Warming will have major effects on permafrost distribution and on ground-ice resulting in a major destabilization of slopes and slumping of soil, and disruption of tundra plant communities. Disruption of peat and moss surfaces lead to loss of insulation, an increase in active-layer depth and changes in drainage and plant assemblages. Increases of UV-B radiation will strongly affect vulnerable populations of both plants and animals. The indigenous peoples will face major changes in life style, edibility of food and health standards, if there is a significant warming trend. The great need is for information which is sensitive to the changes and will assist in developing an understanding of the complex interactions of the arctic biota, human populations and the physical environment.  相似文献   

15.
马鞍山市酸雨污染分析及控制对策研究   总被引:6,自引:0,他引:6  
从马鞍山市降水常规监测数据资料入手 ,比较详细地分析了该市酸雨时空分布特征、原因以及降水酸度和酸雨频率年度变化情况 ,并结合马鞍山市有关环境资料对该市酸雨发展趋势作了较深的分析 ,也对酸雨污染控制对策作了一定的研究探讨。研究结果表明 ,该市存在酸雨污染问题 ,上半年比下半年污染重 ,主要集中在一中点 ,二氧化硫是影响降水酸度的主要因素 ,酸雨类型以硫酸型为主。随着经济发展 ,酸雨污染有扩大趋势 ,必须采取果断措施进行治理。  相似文献   

16.
图们市大气颗粒物中重金属含量及分布特征   总被引:2,自引:2,他引:2  
采集了图们市2006年秋、冬两季的TSP和PM10样品,采用湿法消解-原子吸收分光光度法测定了其中的铅、镉、饲、锌、铬、铁、锰7种重金属.结果表明,图们市大气颗粒物中重金属含量由高到低的顺序是Fe>Cr>Zn>Pb>Mn>Cu>Cd.多数重金属元素含量冬季高于秋季,在一天之内早晨的重金属浓度也往往高于晚上争中午,说明大气颗粒物的来源包括天然源和人为源.  相似文献   

17.
2006年秋冬两季图们市大气气溶胶中多环芳烃分布规律   总被引:1,自引:0,他引:1  
大气气溶胶是目前大多数城市的首要污染物,其中的多环芳烃是对人体健康危害最大的环境污染物之一。通过图们市2006年9月、12月4个采样点的大气气溶胶样品分析,研究了大气气溶胶中多环芳烃的分布规律。采用超声波萃取法提取样品中的多环芳烃,然后对其进行旋蒸浓缩,氮气吹至1ml,用高效液相色谱进行定性和定量分析。实验结果表明,美国EPA优先控制的16种多环芳烃普遍存在于图们市区的大气气溶胶中。图们市不同时空大气气溶胶中多环芳烃的分布具有一定的规律性。  相似文献   

18.
太湖氮磷大气干湿沉降时空特征   总被引:10,自引:0,他引:10  
为了探索太湖氮磷营养盐干湿沉降特征及对太湖营养盐输入的贡献,于2011年不同季节采集太湖不同位点的大气干湿沉降样品,分析干湿沉降中氮(N)和磷(P)的形态和沉降量。研究结果表明,输入太湖的磷以干沉降为主,而氮以湿沉降为主。在太湖干沉降中总无机氮(TIN)占总氮(TN)的77.1%,溶解性磷(DIP)占总磷(TP)的77.9%。干沉降中TIN主要以NH+4-N为主。西太湖是TN与TP通过大气干湿沉降输入太湖的最高湖区。太湖全年大气TN沉降总量为20 978 t,TP沉降总量为1 268 t,因此,氮磷大气干湿沉降是太湖营养盐输入的重要来源之一。  相似文献   

19.
The social and economic implications of atmospheric change on biodiversity need to be seen in a global context of major shifts in the conceptualization and management of our relationship with nature. Traditionally, we have conceptualized the atmosphere and the other creatures of the biosphere as separate from the human, but their quasi-autonomy is now becoming subject to more and more human management. This raises not only economic issues, but social, political, and ethical concerns that will have substantial influence on public policy. Among these are the commodification of genetic material; the privatization of traditional knowledge; and the management of information. In this broader context, the paper examines an array of current and proposed strategies of response to changes in biodiversity as a result of climatic and other stresses.  相似文献   

20.
根据监测网络通信的特点,设计了大气监测网络通信体系,并在系统中引入了学习算法和缓存机制,有效地提高了大气监测网络通信系统的灵活性和效率。  相似文献   

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