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891.
Anthropogenic activities are responsible for the emission of gaseous and particulate pollutants that modify atmospheric composition. Such changes are, in turn, responsible for the degradation of air quality at the regional/local scale as well as for changes of climate. Air pollution and climate change are two intimately connected environmental issues. However, these two environmental challenges are still viewed as separate issues, which are dealt with by different science communities and within different policy frameworks. Indeed, many mitigation options offer the possibility to both improve air quality and mitigate climate change but, at the same time, mitigation options that may provide benefits to one aspect, are worsening the situation in the other. Therefore, coordinated actions taking into account the air quality-climate linkages are required. These actions need to be based on strong scientific grounds, as recognised by the European Commission that in the past few years has promoted consultation processes among the science community, the policy makers and the relevant stakeholders. Here, the main fields in which such coordinated actions are needed are examined from a policy perspective.  相似文献   
892.
Two measurement campaigns of volatile organic compounds (VOC) were carried out in the industrial city of Dunkerque, using Radiello passive samplers during winter (16–23 January) and summer (6–13 June) 2007. 174 compounds were identified belonging to six chemical families. Classifying sampling sites with similar chemical profiles by hierarchical ascending classification resulted in 4 groups that reflected the influence of the main industrial and urban sources of pollution. Also, the BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) quantification allowed us to map their levels of concentration. Benzene and toluene (BT) showed high concentrations in Northern Dunkerque reflecting the influence of two industrial plants. Differences among spatial distributions of the BT concentrations over contrasted meteorological conditions were also observed. An atypical ratio of T/B in the summer samples led us to investigate the BTEX origins shedding light on the contribution of pollutants transported across various zones of VOC emissions situated in Europe.  相似文献   
893.
Since the last decade the WHO Collaborating Centre for Air Quality Management and Air Pollution Control, Berlin, Germany, operates a quality assurance and control (QA/QC) programme on air quality monitoring in the WHO European Region. As main activity Intercomparison workshops have been established for air monitoring network laboratories on a regular basis to harmonise air quality measurements, analysis and calibration techniques. 36 air hygiene laboratories of public health and environmental institutions of 24 countries participated in twelve Intercomparisons between 1994 and 2004. The majority was carried out for NO, NO2, SO2 and O3. The results were predominantly satisfactory for automatic methods. The results of manual methods were mainly in a good, and for several concentration levels partly very good accordance with the data obtained by the monitors.  相似文献   
894.
The 2008 European Air Quality Directive (AQD) (2008/50/EC) encourages the use of models in combination with monitoring in a range of applications. It also requires Member States to design appropriate air quality plans for zones where the air quality does not comply with the AQD limit values. In order to cope with these various elements, a wide range of different modeling methods have been developed and applied by EU Member States in the last decade to assess the effects of local and regional emission abatement policy options on air quality and human health. However, an overall review of the methodologies that are used in different countries to compile local and regional air quality plans has not been performed so far. Such a review has been the objective of the APPRAISAL EU FP7 project with the main goal to identify methodologies and their limitations and to propose possible key areas to be addressed by research and innovation on the basis of this review. To fulfill these objectives, a structured online database of methodologies has been developed in collaboration with experts involved in the design of air quality plans (AQP). The current work relies on the APPRAISAL database which currently totals 59 contributions from 13 Member States. In this paper we summarize the outcome of the APPRAISAL project with respect to the review of current Integrated Assessment Modeling practices.  相似文献   
895.
矿井风流年龄与矿井空气品质分析   总被引:3,自引:1,他引:2  
矿井空气品质是矿井通风理论的新思路,是人们认识矿井空气环境的一种科学方法。通过对矿井风流年龄与矿井空气品质分析,重点论述和讨论了矿井风流年龄的定义及其计算;矿井风流污染物的定义,通风分支均匀释放污染物时分支空气污染物浓度的计算,局部集中散发污染物的分支污染物浓度计算;矿井空气品质的定义,任意分支空气品质的计算,分支汇合点的空气品质计算;研究了矿井风流空气品质随时间、空间变化的动态性,分析了矿井空气品质与矿井风流年龄及污染物的关系。矿井空气品质是矿井通风设计和评价矿井风流质量的重要理论依据  相似文献   
896.
Critical Loads and levels have played a centralrole in the successful development of effect-based emissionreduction strategies for Europe in the fields of acidification,eutrophication and ground-level ozone. The aim of theInternational Programme on Mapping Critical Loads and Levelsled by Germany, with participation of 24 countries, is todetermine critical loads and levels for forest, crops, naturalvegetation, soils, water and materials. The exceedances ofcritical loads and critical levels are used to quantify the riskfor environmental damage by air pollution and tosupport the development of optimised abatement strategies.  相似文献   
897.
大气监测质量保证是一项室内外密切配合的系统工程,每一个步骤对测值都有影响。为提高大气中氮氧化物测定值的准确性,我站采用双管平行对比采样,在长期实践中总结出从室外采样到室内样品分析质量保证方法和经验,以保证大气中氮氧化物测值准确可靠。  相似文献   
898.
Sulphur dioxide (SO2) emissions cause acidification and human health problems which are, despite present policy instruments, projected to remain even after 2030 in Europe. Additional instruments are needed to solve the problems, and impact analysis of already used policy instruments would contribute to the development of new effective instruments. We present a study on how much of the decoupling of SO2 emissions from economic growth 1990–2012 that was due to SO2 policy instruments in general and to what extent it is possible to estimate the impact of individual instruments. Focus is on Sweden, a country with problems reaching its SO2-related environmental policy targets and with detailed data available.We applied decomposition analysis combined with an analysis of the chronological development of emission factors and mandated emission limits. Our use of official emission inventory data and publicly available data on the development of SO2 policy instruments increase the usefulness of our results to policy makers.The results indicate that at least 26–27% (corresponding to ∼35–36 ktonne annually) of the decoupling 1990–2012 was due to SO2 policy instruments. 4–5% (∼6–7 ktonne) of the decoupling was caused by one environmental permit decision and stricter sulphur emission limit for marine oils. Most of the total impact of SO2 policy instruments could not be causally connected to an individual instrument, because many events and developments overlap in time.The implications of the results are that: a) SO2 policy instruments should still be important to reduce SO2 emissions in many countries; b) a lower boundary total emission impact of SO2 policy instruments can be estimated, but with current knowledge and data the impacts of individual instruments are rarely possible to estimate. Research on how to increase the precision in total impact estimates of SO2 policy instruments is needed to improve future impact analyses. More detailed emission inventory data would improve impact analysis of individual instruments.  相似文献   
899.
Abstract

Ametpreviously described by Mann et al.1 for the determination of hexachlorobenzene in air was modified to detect DBCP in air at the level of 0.02 ppb (by volume). The method utilizes Chromosorb 101 as a trapping medium with subsequent analysis of the eluted DBCP by electron capture ‐ gas chromatography. The procedure was tested using air flows of 1 1/min to 5 1/min for sampling periods of 30 min to 3 hr. Recoveries of greater than 90% were obtained for DBCP levels ranging from 0.07 ppb to 20 ppm. More than 90% of the DBCP stored on Chromosorb 101 at ambient temperature for one month was recovered. A one‐half acre field plot was sprayed with DBCP using the drench method. Air samples were taken from the breathing zone of the applicator during the mixingspraying and clean‐up procedures. Air samples were also taken periodically around the perimeter of the plot for up to 7 days after spraying.  相似文献   
900.
This work analyzes the performance of an innovative biogas upgrading method, Alkali absorption with Regeneration (AwR) that employs industrial residues and allows to permanently store the separated CO2. This process consists in a first stage in which CO2 is removed from the biogas by means of chemical absorption with KOH or NaOH solutions followed by a second stage in which the spent absorption solution is contacted with waste incineration Air Pollution Control (APC) residues. The latter reaction leads to the regeneration of the alkali reagent in the solution and to the precipitation of calcium carbonate and hence allows to reuse the regenerated solution in the absorption process and to permanently store the separated CO2 in solid form. In addition, the final solid product is characterized by an improved environmental behavior compared to the untreated residues. In this paper the results obtained by AwR tests carried out in purposely designed demonstrative units installed in a landfill site are presented and discussed with the aim of verifying the feasibility of this process at pilot-scale and of identifying the conditions that allow to achieve all of the goals targeted by the proposed treatment. Specifically, the CO2 removal efficiency achieved in the absorption stage, the yield of alkali regeneration and CO2 uptake resulting for the regeneration stage, as well as the leaching behavior of the solid product are analyzed as a function of the type and concentration of the alkali reagent employed for the absorption reaction.  相似文献   
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