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181.
Common deficiencies in the typical evaluation of the surface water quality impacts of hazardous chemical sites are discussed. Particular attention is given to deficiencies in monitoring stormwater runoff, as well as the input of contaminated groundwaters that lead to impairment of the beneficial uses of nearby surface waters because of site-derived hazardous and deleterious chemicals. An alternative approach, Evaluation Monitoring, is presented in this paper. Evaluation Monitoring shifts the monitoring program from periodic sampling and analysis of stormwater runoff and ambient waters for a suite of chemical parameters, to examining the receiving waters to determine what, if any, water quality use impairments are occurring in surface waters due to the runoff-associated constituents and shallow groundwater input.  相似文献   
182.
Increasingly, the public and governmental agencies are concerned about remediating and reclaiming contaminated sites. Understanding the ecological resources on-site and valuing those resources in terms of future uses is important for determining suitable future land uses. In this article, we suggest the major categories of natural resource information required by managers, policy makers, and the general public for making initial future land-use determinations. We then use a dataset of 25 Department of Energy (DOE) sites slated for remediation to explore whether such data are readily available and whether the data can be used to assess natural resource value. Although information is available for almost all sites on federally endangered and threatened species, this information is less available for state-listed species. Biodiversity information is available only for some sites for birds (N = 17), mammals (N = 15), reptiles (N = 14), amphibians (N = 13), and plants (N = 11) and is almost nonexistent for invertebrates (N = 2). Some information is available for invasive species (N = 9). The number of available habitats is directly related to total acres and nonindustrial acres. Biodiversity of birds, mammals, and reptiles (but not amphibians) is directly related to both total acres and total nonindustrial acres of sites. These data suggest that even over a wide geographical area (from eastern to western United States), biodiversity relates to habitat size and number of habitats available. This information will be useful not only to DOE managers but also to natural resource trustees, ecologists, state and federal regulators, and the general public in the discourse over future uses of these lands.*Published online Author to whom correspondence should be addressed; Joanna Burger  相似文献   
183.
184.
99Tc in seawater in the West Spitsbergen Current and adjacent areas   总被引:2,自引:0,他引:2  
99Tc levels were measured in seawater samples collected between 2000 and 2002 in the West Spitsbergen Current (WSC) and along the western coast of Svalbard or Spitzbergen and compared with available oceanographic 3-D modelling results for the late 1990s. Additional data from related regions are also presented in order to support the data interpretation. The seawater in the Arctic fjord Kongsfjorden on the western coast of Svalbard is influenced by the WSC, as shown by the 99Tc levels in surface water. By means of the WSC, 99Tc reaches the Eastern Fram Strait, where one branch of the WSC turns west into the East Greenland Current (EGC), and another branch continues northwards into the Arctic Ocean. Surface seawater collected in the central part of the WSC during a cruise on board the R/V "Polarstern" in the summer of 2000, showed higher levels of (99)Tc than samples measured in Kongsfjorden in the spring of 2000. However, all levels measured in surface water are of the same order of magnitude. Data from sampling of deeper water in the WSC and EGC provide information pertaining to the lateral distribution of 99Tc. In all vertical profiling surveys (conducted in spring and summer), the highest levels of 99Tc were found in surface water. Comparison with oceanographic 3-D modelling indicates both significant seasonal variations in the lateral stratification of the WSC and variations with depth over shorter vertical distances. This information can be applied in sampling strategies, environmental monitoring, long-range transport of pollutants and physical oceanography.  相似文献   
185.
Legume root nodules are the site of biological nitrogen fixation in theRhizobium-legame symbiosis. Nodules are structures unique to this symbiosis and they are morphologically as well as physiologically distinct from other plant organs. Organic substances affecting the macro- or microsymbionts vitality, such as PAHs (Wetzel et al., 1991), reduce nodulation even before visible damage to the plant can be detected. We present data that the formation of nodules (nodulation) may also serve for ecotoxicological evaluation of heavy metals in different binding states. Tests were performed in petri dishes with alfalfa (lucerne) seedlings inoculated withRhizobium meliloti. Cultivation took place in growth cabinets with carefully standardized and documented growth conditions. Data from stressed plants was recorded after 14 days of cultivation on contaminated substrate. A dose responsive decrease in nodulation was found after application of cadmium acetate, cadmium iodide, cadmium chloride, sodium salts of arsenate and arsenite, arsenic pentoxide, and lead nitrate, whereas lead acetate showed no effect up to a concentration of 3 μM. The dose response curves were used to calculate EC10, EC50 and EC90 values. EC50 values for cadmium compounds range from 1.5 to9.5 pM. Testing different arsenic compounds results in EC50 from 2.6 to 20.1 μM. EC50 of lead nitrate is 2.2 μM. The sensitivity, reproducibility and reliability of this test system is discussed compared to established biotests.  相似文献   
186.
Safety at Finnish work places is mainly considered to be the task of a separate safety organization, e.g., a safety manager and safety delegates. However, it is the supervisor who is responsible for the daily safety in the departments. The Finnish paper industry has developed a supplementary system for the safety organization to carry out safety work in the factories. The monitoring and improving of the daily safety has been delegated to small groups in the production departments. These small groups consist of the supervisor and the safety representative (worker member) of the work area. Sometimes also a department manager or a member of the maintenance department may participate in the work group. A training program was designed to give basic knowledge and skills for the groups. The course has helped the participants to better outline their duties and activities within the safety field.  相似文献   
187.
A method using GC-MS and derivatization with N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA) was developed for the analysis of 20 phenolic compounds in atmospheric samples (gas and particles). Air sampling was carried out using a Hi-Vol sampler with glass fibre filter and XAD-2 resin at a flow rate of 60 m(3) h(-1). The particle and gas phases were collected separately over a period of 4 h. Samples were Soxhlet extracted, evaporated to dryness under nitrogen and refilled with acetonitrile. 100 microl of these extracts were derivatized with 100 microl of MTBSTFA at 80 degrees C for 1 h under strong stirring. Phenolic compounds were injected into a GC-MS in splitless mode and quantified as their TBDMS derivatives in the SIM mode. Mass spectral analysis of the derivatives of the 20 compounds studied indicates that the spectra are highly specific showing an ion at [M - 57]+ which is useful for structure confirmation or analysis at low levels using selected ion monitoring. Quantification limits varied between 5 microg l(-1) and 10 microg l(-1) which correspond to 20 pg m(-3) and 40 pg m(-3) for 250 m(3) of air sampled. This method was successfully applied to atmospheric samples.  相似文献   
188.
Passive samplers were used to monitor ammonia concentrations at rural inner alpine and pre-alpine, as well as urban, sites in Austria and Bavaria. Elevated concentrations were measured both at farms (up to 36 microg NH3 m(-3)) and at urban locations (up to 28 microg NH3 m(-3)). At urban locations a linear relationship between the traffic density and the NH3 concentration was found, but there was no marked seasonal trend. The highest ammonia concentrations were measured in a traffic tunnel (up to 78 microg NH3 m(-3)). The presence of livestock breeding or small scale alpine pastures resulted in elevated concentrations at the rural sites (8.1-12 and 2.5-4.6 microg NH3 m(-3), respectively), compared to the surrounding areas (3.1 and 0.9 microg NH3 m(-3)). Agriculture related sources are usually limited either spatially or seasonally. As the emissions were moderate in our case, a rapid removal and dilution of ammonia was possible and therefore the NH3 burden was only local. Sources related to traffic are more evenly distributed both geographically and seasonally. The WHO guideline, annual average concentration of 8 microg m(-3) for the protection of vegetation, was only exceeded at farms, at the urban station with the heaviest traffic and in the Tauerntunnel.  相似文献   
189.
The influence of oxidation and ripening on the kinetics of heavy metal release from anoxic sediments was investigated by means of porewater analysis and pH(stat) leaching tests. During simulated land disposal of an anoxic river sediment, a considerable heavy metal (Cd, Zn and Ni) release into the porewater was observed after 25 days of exposure of the sediment to the air. The release kinetics of Cd and Zn during pH(stat) leaching indicated that their release was related to the oxidation of Cd- and Zn-sulfides. It was not completely clear whether the release of Ni was due to the oxidation of Ni-sulfides or to the introduction of H(+)(generated by the oxidation of sulfides or introduced by titration). The release of Cu seemed to be explained by the oxidation of both Fe-sulfides and Cu-sulfides. As such, pH(stat) experiments provided an indirect way to assess the mineralogy of the anoxic sediment. During ripening of the sediment, the release rate of Zn and Cd in pH(stat) leaching tests increased. For Ni, however, a similar release pattern was observed in the anoxic sediment and in the ripened sediments. Two weeks' drying at 100 degrees C resulted in an increase in the leachability of Cu. Nevertheless, at pH 4 and 6, the thermally treated sediment displayed a slower leaching of Cd and Zn than the ripened sediment. Although thermal treatment is often used to simulate ageing in soils, it cannot be used to simulate ripening of anoxic sediments.  相似文献   
190.
This article details the results of an investigation into the application of geostatistical data analysis to two environmentalradiometric time series. The data series employed consist of 99Tc values for seaweed (Fucus vesiculosus) and seawater samples taken as part of a marine monitoring program conducted on the coast of northern Norway by the Norwegian Radiation Protection Authority. Geostatistical methods were selected in order to provide information on values of the variables at unsampled times and to investigate the temporalcorrelation exhibited by the data sets. This information is ofuse in the optimisation of future sampling schemes and for providing information on the temporal behaviour of the variablesin question that may not be obtained during a cursory analysis.The results indicate a high degree of temporal correlation withinthe data sets, the correlation for the seawater and seaweed databeing modelled with an exponential and linear function,respectively. The semi-variogram for the seawater data indicatesa temporal range of correlation of approximately 395 days with noapparent random component to the overall variance structure and was described best by an exponential function. The temporal structure of the seaweed data was best modelled by a linear function with a small nugget component. Evidence of drift was present in both semi-variograms. Interpolation of the data setsusing the fitted models and a simple kriging procedure were compared, using a cross-validation procedure, with simple linearinterpolation. Results of this exercise indicate that, for theseawater data, the kriging procedure outperformed the simpleinterpolation with respect to error distribution andcorrelation of estimates with actual values. Using theunbounded linear model with the seaweed data produced estimatesthat were only marginally better than those produced by thesimple interpolation.  相似文献   
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