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1.
将各类电力设备浸渍剂及其它待鉴定油样品以正己烷残石油醚稀释10万倍,取2μl注入气相色谱仪分析,根据PCB特征峰组对其进行定性,根据特征峰高进行定量。  相似文献   

2.
本文根据物质的组分及来源对天然有机絮凝剂进行了分类,并对这三大类天然高分子絮凝剂的性能、应用、结构及研究发展概况等方面进行了论述  相似文献   

3.
根据启东市第一次全国污染源普查数据,对启东市畜禽养殖污染的现状和成因进行了深入分析,并提出了对畜禽养殖污染防治的对策思考。  相似文献   

4.
对洗像过程中产生的洗像废液按照成分的不同进行分质处理。其中 ,有机废液采用高温焚烧的方法进行处理 ;无机废液根据主要成分的化学性质分别采用中和、氧化等方法进行处理。通过室内试验 ,确定了处理工艺的主要参数 ,并根据试验结果 ,利用废液处理站设施处理了 1.6 4t洗像废液。处理后排放的废水、废气均达到了国家有关排放标准  相似文献   

5.
固体废物中重金属浸出毒性评价方法的研究进展   总被引:1,自引:0,他引:1  
浸出毒性是固体废物的重要特性之一,亦是判别固体废物是否属于危险废物的重要评价指标.根据与溶液接触方式的不同,固体废物浸出毒性评价方法可以划分为批处理实验、柱淋滤实验和恒pH滴定(pH-stat)实验等.对这3种方法的应用方向、特点和缺陷等进行了系统总结.最后还指出,在评价固体废物中重金属的浸出毒性时,可采用几种方法进行对比,还可以根据实验目的和需求对各个实验参数进行改进,从而得出更全面、客观的评价结果.  相似文献   

6.
根据 ISO14 0 0 0标准中对环境因素识别评价的要求 ,并结合实际工作中碰到的问题 ,对如何充分识别环境因素进而评价出重要环境因素进行了分析探讨。  相似文献   

7.
龙平  于苏俊 《污染防治技术》2009,22(3):14-16,94
根据盲数理论,定义了湖泊水环境系统盲参数的概念。在此基础上,结合经验总磷模型,通过对模型参数的盲数化处理,得到各种可能的取值区间及其相对应的可信度。根据对九寨沟内的湖泊,在一个水文年的监测资料的分析,采用Vollenweider式的经验总磷模型,对各个湖泊进行了总磷的平衡浓度预测。  相似文献   

8.
空气污染暴露评价研究进展   总被引:5,自引:1,他引:5  
介绍了暴露及暴露评价的基本概念、人体空气污染暴露评价的指示物及其特征,讨论暴露评价方法的类型,对各种方法的优、缺点进行了比较分析。根据综述和案例分析情况,对空气污染暴露评价研究的发展趋势进行了展望。  相似文献   

9.
浙江省大气污染造成的经济损失初步估算   总被引:13,自引:1,他引:12  
根据1996年浙江省大气污染监测结果,应用有关环境经济学的价值计算方法,对浙江省大气污染造成的经济损失进行了初步估算,结果表明,1996年浙江省大气污染经济损失约为34.85亿元。  相似文献   

10.
酸析+CASS+气浮工艺处理浆粕废水中试研究   总被引:1,自引:0,他引:1  
根据粘胶纤维生产特点,对某厂浆粕黑液废水采用酸析+CASS+气浮工艺技术进行处理。中试研究表明:处理后出水COD<100mg/L、BOD<20mg/L、SS<70mg/L、色度<70倍、Zn<2.0mg/L,除色度外,各项指标可以满足GB89781996一级排放标准要求。并且根据中试装置的运行进行了经济技术分析,为工程设计提供理论依据。  相似文献   

11.
12.
Grigorakis K  Rigos G 《Chemosphere》2011,85(6):899-919
Aquatic farming has been considered, during the last decades, as the fastest growing food production industry powered by governmental and technological impulsion. Compensation for fisheries decline, creation of new jobs and source of financial windfall are the most important benefits. However, similar to most of the human food-production activities, aquaculture raised several issues related to the environmental welfare and consumer safety. An effort to record the aquaculture-environment and -human safety interactions with regard to the Mediterranean mariculture, is attempted herein. We focused on this geographical area due to its individualities in both the hydrological and physicochemical characteristics and the forms of aquaculture activities. The cage farming of euryhaline marine fish species and more recently of bluefin tuna and mollusk farming are the dominating aquaculture activities. The impacts of these activities to the environment, through wastes offloads, introduction of alien species, genetic interactions, disease transfer, release of chemicals, use of wild recourses, alterations of coastal habitats and disturbance of wildlife, are analytically considered. Also the consumer safety issues related to the farming are assessed, including generation of antibiotic-resistant microorganisms, contaminants transferred to humans though food chain and other hazards from consumption of aquacultured items. Within these, the major literature findings are critically examined and suggestions for scientific areas that need further development are made. The major tasks for future aquaculture development in this region are: (i) to ensure sustainability and (ii) to balance the risks to public or environmental health with the substantial economical benefits. In regard with monitoring, tools must be created or adapted to predict the environmental costs and estimate consumer impact. At a canonistic and legal basis, the establishment of appropriate legal guidelines and common policies from all countries involved should be mandatory.  相似文献   

13.
Integrated testing and intelligent assessment—new challenges under REACH   总被引:1,自引:1,他引:0  
BACKGROUND, AIM AND SCOPE: Due to a number of drawbacks associated with the previous regime for the assessment of new and existing chemicals, the European Union established a new regulation concerning the registration, evaluation, authorisation and restriction of chemicals (REACH). All relevant industrial chemicals must now be assessed. Instead of the authorities, industry itself is responsible for the risk assessment. To achieve better and more efficient assessments while reducing animal testing, all information-standard, non-standard and non-testing-has to be used in an integrated manner. To meet these challenges, the current technical guidance documents for risk assessment of new and existing chemicals had to be updated and extended considerably. This was done by experts in a number of REACH Implementation Projects. This paper presents the most relevant results of the expert Endpoint Working Group on Aquatic Toxicity in order to illustrate the change of paradigm in the future assessment of hazards to the aquatic environment by chemical substances. MAIN FEATURES AND CHALLENGES: REACH sets certain minimum data requirements in order to achieve a high level of protection for human health and the environment. It encourages the assessor to use alternative information instead of or in addition to standard one. This information has to be equivalent to the standard information requirement and adequate to draw overall conclusions with respect to the regulatory endpoints classification and labelling, persistent, bioaccumulative and toxic (PBT) assessment and predicted no-effect concentrations (PNEC) derivation. The main task of the expert working group was to develop guidance on how to evaluate the toxicity of a substance based on integration of information from different sources and of various degrees of uncertainty in a weight of evidence approach. INTEGRATED TESTING AND INTELLIGENT ASSESSMENT: In order to verify the equivalence and adequacy of different types of information, a flexible sequence of steps was proposed, covering characterisation of the substance, analysis of modes of action, identification of possible analogues, evaluation of existing in vivo and in vitro testing data as well as of QSAR results. Finally, all available data from the different steps have to be integrated to come to an overall conclusion on the toxicity of the substance. This weight of evidence approach is the basis for the development of integrated testing strategies (ITS), in that the available evidence can help to determine subsequent testing steps and is essential for an optimal assessment. Its flexibility helps to meet the different requirements for drawing conclusions on the endpoints classification and labelling, PNEC derivation as well as PBT assessment. The integration of all kinds of additional information in a multi-criteria assessment reduces the uncertainties involved with extrapolation to the ecosystem level. The weight of evidence approach is illustrated by practical examples. CONCLUSIONS AND PERSPECTIVES: REACH leads to higher challenges in order to make sound decisions with fewer resources, i.e. to move away from extensive standard testing to an intelligent substance-tailored approach. Expert judgement and integrated thinking are key elements of the weight of evidence concept and ITS, potentially leading to better risk assessments. Important sub-lethal effects such as endocrine disruption, which are not covered by the current procedure, can be considered. Conclusions have to be fully substantiated: Risk communication will be an important aspect of future assessments.  相似文献   

14.
This perspective paper argues for an urgent need to monitor a set of 12 concrete, measurable indicators of food and water security in the Arctic over time. Such a quantitative indicator approach may be viewed as representing a reductionist rather than a holistic perspective, but is nevertheless necessary for actually knowing what reality aspects to monitor in order to accurately understand, quantify, and be able to project critical changes to food and water security of both indigenous and non-indigenous people in the Arctic. More relevant indicators may be developed in the future, taking us further toward reconciliation between reductionist and holistic approaches to change assessment and understanding. However, the potential of such further development to improved holistic change assessment is not an argument not to urgently start to monitor and quantify the changes in food and water security indicators that are immediately available and adequate for the Arctic context.  相似文献   

15.
Since lichens lack roots and take up water, solutes and gases over the entire thallus surface, these organisms respond more sensitively to changes in atmospheric purity than vascular plants. After centuries where effects of sulphur dioxide and acidity were in the focus of research on atmospheric chemistry and lichens, recently the globally increased levels of ammonia and nitrate increasingly affect lichen vegetation and gave rise to intense research on the tolerance of lichens to nitrogen pollution. The present paper discusses the main findings on the uptake of ammonia and nitrate in the lichen symbiosis and to the tolerance of lichens to eutrophication. Ammonia and nitrate are both efficiently taken up under ambient conditions. The tolerance to high nitrogen levels depends, among others, on the capability of the photobiont to provide sufficient amounts of carbon skeletons for ammonia assimilation. Lowly productive lichens are apparently predisposed to be sensitive to excess nitrogen.  相似文献   

16.
The assessment of aquifer vulnerability is a very important task, especially in agricultural areas because the quality and availability of groundwater affects both the sustainability of agriculture and the quality of life. In this study, an integrated approach is considered, with the use of the generic and agricultural DRASTIC models as well as a geographic information system (GIS), to assess groundwater vulnerability in the agricultural area of Barrax, in the province of Albacete, in Spain. Seven parameters—depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone media, and hydraulic conductivity of the aquifer (DRASTIC)—have been considered as weighted layers to enable an accurate groundwater risk mapping. The results of the generic DRASTIC model indicated very low vulnerability to contamination for Barrax groundwater due to limited urban and industrial development in the wider area. However, agricultural activities impose pressure to groundwater resources and the results of the agricultural DRASTIC model show that 6.86% of the study area is characterized by very high, 2.29% by high, 47.28% by medium, 38.28% by low, and the remaining 5.29% by no vulnerability to groundwater contamination. The distribution of nitrate concentration in groundwater in the area under study is quite well correlated with the agricultural DRASTIC vulnerability index. Sensitivity analysis was also performed to acknowledge statistical uncertainty in the estimation of each parameter used, to assess its impact, and thus to identify the most critical parameters that require further investigation. Depth to water and impact of vadose zone are the parameters that had the most noticeable impact on the generic DRASTIC vulnerability index followed by the soil media and topography. In contrast, the agricultural DRASTIC method is more sensitive to the removal of the depth to water parameter followed by the topography and the soil media parameters.  相似文献   

17.
Callaghan TV  Tweedie CE  Webber PJ 《Ambio》2011,40(6):555-557
Polar and alpine environments are changing rapidly due to increases in temperature, which are amplified in the Arctic, as well as changes in many local factors. The impacts on ecosystems and their function have potential consequences for local residents and the global community. Tundra areas are vast and diverse, and the knowledge of geographical variation in environmental and ecosystem change is limited to relatively few locations, or to remote sensing approaches that are limited mostly to the past few decades. The International Polar Year, IPY, provided a context, stimulus and timely opportunities for re-visiting old research sites and data sets to collate data on past changes, to pass knowledge from old to new generations of researchers and to document environmental characteristics of sites to facilitate detection and attribution of future changes. Consequently, the project “Retrospective and Prospective Vegetation Change in the Polar Regions: Back to the Future,” BTF, was proposed and endorsed as an IPY activity (project #512). With national funding support, teams of researchers re-visited former sites and data sets throughout the Arctic and some alpine regions. These efforts have amounted to a gamut of “BTF” studies that are collectively geographically expansive and disciplinary diverse. A selection of these studies are introduced and presented in the current issue together with a brief synthesis of their findings.  相似文献   

18.
The Baltic Sea Action Plan (BSAP) requires tools to simulate effects and costs of various nutrient abatement strategies. Hierarchically connected databases and models of the entire catchment have been created to allow decision makers to view scenarios via the decision support system NEST. Increased intensity in agriculture in transient countries would result in increased nutrient loads to the Baltic Sea, particularly from Poland, the Baltic States, and Russia. Nutrient retentions are high, which means that the nutrient reduction goals of 135 000 tons N and 15 000 tons P, as formulated in the BSAP from 2007, correspond to a reduction in nutrient loadings to watersheds by 675 000 tons N and 158 000 tons P. A cost-minimization model was used to allocate nutrient reductions to measures and countries where the costs for reducing loads are low. The minimum annual cost to meet BSAP basin targets is estimated to 4.7 billion €.  相似文献   

19.
Phytoremediation of polyaromatic hydrocarbons, anilines and phenols   总被引:12,自引:0,他引:12  
Phytoremediation technologies based on the combined action of plants and the microbial communities that they support within the rhizosphere hold promise in the remediation of land and waterways contaminated with hydrocarbons but they have not yet been adopted in large-scale remediation strategies. In this review plant and microbial degradative capacities, viewed as a continuum, have been dissected in order to identify where bottle-necks and limitations exist. Phenols, anilines and polyaromatic hydrocarbons (PAHs) were selected as the target classes of molecule for consideration, in part because of their common patterns of distribution, but also because of the urgent need to develop techniques to overcome their toxicity to human health. Depending on the chemical and physical properties of the pollutant, the emerging picture suggests that plants will draw pollutants including PAHs into the plant rhizosphere to varying extents via the transpiration stream. Mycorrhizosphere-bacteria and -fungi may play a crucial role in establishing plants in degraded ecosystems. Within the rhizosphere, microbial degradative activities prevail in order to extract energy and carbon skeletons from the pollutants for microbial cell growth. There has been little systematic analysis of the changing dynamics of pollutant degradation within the rhizosphere; however, the importance of plants in supplying oxygen and nutrients to the rhizosphere via fine roots, and of the beneficial effect of microorganisms on plant root growth is stressed. In addition to their role in supporting rhizospheric degradative activities, plants may possess a limited capacity to transport some of the more mobile pollutants into roots and shoots via fine roots. In those situations where uptake does occur (i.e. only limited microbial activity in the rhizosphere) there is good evidence that the pollutant may be metabolised. However, plant uptake is frequently associated with the inhibition of plant growth and an increasing tendency to oxidant stress. Pollutant tolerance seems to correlate with the ability to deposit large quantities of pollutant metabolites in the 'bound' residue fraction of plant cell walls compared to the vacuole. In this regard, particular attention is paid to the activities of peroxidases, laccases, cytochromes P450, glucosyltransferases and ABC transporters. However, despite the seemingly large diversity of these proteins, direct proof of their participation in the metabolism of industrial aromatic pollutants is surprisingly scarce and little is known about their control in the overall metabolic scheme. Little is known about the bioavailability of bound metabolites; however, there may be a need to prevent their movement into wildlife food chains. In this regard, the application to harvested plants of composting techniques based on the degradative capacity of white-rot fungi merits attention.  相似文献   

20.
Jančula D  Maršálek B 《Chemosphere》2011,85(9):1415-1422
Cyanobacteria proliferation is among the most threatening consequences of freshwater pollution. Health risks from human and other-organism exposure to cyanobacteria have led to an effort to find practical methods for cyanobacterial water-bloom reduction. Hence, methods and techniques have been developed in order to reduce the amount of phosphorus or to decrease the abundance of nuisance phytoplankton species directly in the water bodies (in-lake measures). Although these “acute” methods do not solve the problem of catchment area eutrophication, they are cheaper, easier to manage, and for some areas they are the only way to protect human and environmental health against massive cyanobacterial proliferation. This review summarizes the extent of knowledge and published data about the management using metals (Al, Fe, Cu, Ag, Ca), photosensitizers (hydrogen peroxide, phthalocyanines, TiO2), herbicides and chemicals derived from natural compounds as fast and efficient removal agents of cyanobacteria. This review concludes that some compounds, when non-persistent and ecotoxicologically acceptable may help to manage cyanobacterial blooms in an efficient way compared to previous methods (e.g. copper sulfate).  相似文献   

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