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81.
The present work investigates electricity production using a high efficiency electrochemical generator that employs as fuel a biogas from the dry anaerobic digestion of the organic fraction of municipal solid waste (OFMSW).The as-produced biogas contains several contaminants (sulfur, halogen, organic silicon and aromatic compounds) that can be harmful for the fuel cell: these were monitored via an innovative mass spectrometry technique that enables for in-line and real-time quantification.A cleaning trap with activated carbons for the removal of sulfur and other VOCs contained in the biogas was also tested and monitored by observing the different breakthrough times of studied contaminants.The electrochemical generator was a commercial Ni anode-supported planar Solid Oxide Fuel Cell (SOFC), tested for more than 300 h with a simulated biogas mixture (CH4 60 vol.%, CO2 40 vol.%), directly fed to the anode electrode. Air was added to promote the direct internal conversion of CH4 to H2 and CO via partial oxidation (POx).The initial breakthrough of H2S from the cleaning section was also simulated and tested by adding ~1 ppm(v) of sulfur in the anode feed; a full recovery of the fuel cell performance after 24 h of sulfur exposure (~1 ppm(v)) was observed upon its removal, indicating the reliable time of anode exposure to sulfur in case of exhausted guard bed.  相似文献   
82.
This study describes the conservation status of dune systems in relation to disturbance factors in the coastal stretch of the Viterbo province, Latium Region, Italy. Particular emphasis was given to the bioindication value of plant communities and their sequence. Each plant community was considered as a "habitat" in accordance with Annex I of the Directive 92/43/EU. Stress factors, such as sand dynamic and erosion, and anthropogenic pressures, such as trampling and bathing settlements, influence the sequence of habitats and weaken the system of relations that makes these coenoses to occur in extreme conditions. The choice to carry out surveys along wide transects, recording different data, allowed to explore the use of habitats as bioindicators. Comparing sites characterized by the same extension in a homogeneous area, it was possible to expand the use of canonical correspondence analysis (CCA) as a tool to correlate habitat composition and disturbance factors. The application of CCA showed a high correlation of degradation and habitat loss with coastal erosion, trampling and presence of waste. Furthermore, floristic surveys allowed the application of different biodiversity indices to quantify species richness of sampled areas. The conservation status of the sites investigated was found to be diverse, from the total disappearance of the mobile dune habitats to their complete sequence. The proposed methodology has been useful to fulfill the objective of the work and is applicable to other case studies in the Mediterranean.  相似文献   
83.
Over the past two decades, communication on environmental values, actions and performance has become an essential activity of organisations, because of the increased public concern and legislation related to the environment.

Stakeholders put pressure on companies to take environmental responsibility. In this framework, an effective environmental communication can generate value-added on companies' environmental work, and consequently, their competitiveness and profitability can benefit from communicating their environmental responsibility.

In 2006, the International Organization for Standardization (ISO) launched a standard for environmental communication, ISO 14063. ISO 14063 should not be used for third-party certification purposes. Instead, it is intended to be used as a guideline and support companies to ensure successful environmental communication. The aim of this paper is to prompt a discussion about the applicability of the standard ISO 14063 not only to single organisations but as a tool to plan the environmental communication strategy of a whole territorial area. This is achieved by performing a case study relating to the Interreg IVC-funded project “Progresland”. The project involved three Italian and one Spanish natural areas and demonstrated that ISO 14063 could be a valid support to define and implement an environmental communication plan for a territorial area.  相似文献   
84.
85.

Introduction  

The concentrations of trace metals, ionic species, and carbonaceous components in PM10 (particulate matter with aerodynamic diameters smaller than 10 μm) were measured from samples collected near an industrial complex, primarily composed of cement plants, in southeastern Spain, from September 2005 to August 2006.  相似文献   
86.
Northern Latium (Italy) is an area where the Rn risk rate is potentially high because of the extensive outcropping of Neogene U-rich volcanics and the presence of major active tectonic lineaments. The lack of data on Rn risk rates in that area, which is undergoing major urban and industrial development, has prompted this study. It proposes a methodology to evaluate the maximum potential diffusive Rn flux from soils based on the measurement of 226Ra, 232Th and 40K activities by γ-ray spectrometry, and the measurement of main soil parameters influencing the Rn emanation. This methodology provides a simple, reliable and low-cost tool for drawing up radon flux maps useful to both public planners and private individuals, who want to operate safely in the study area. The proposed methodology may also be applied to other geographic areas outside the prescribed study area.  相似文献   
87.
Aqueous solutions of Fenton's reagent (Fe2+ + H2O2) have been used to effect the total decomposition of the chlorophenols: 2-chlorophenol, 3-chlorophenol, 4-chlorophenol, 3,4-dichlorophenol and 2,4,5-trichlorophenol. The mineralization of these chlorinated aromatic substrates to CO2 and free Cl has been studied as a function of [Fe2+] and [HClO4]. Increasing the concentration of Fe2+ enhances the decomposition process, while an increase in the concentration of HClO4, inhibits the reaction. The presence of Fe3+ alone (without any Fe2+) with H2O2 has no effect on the degradation of the chlorophenols. In all cases, the stoichiometric quantity of free Cl was obtained at the completion of the decomposition reaction; but the rates of disappaearance of the chlorophenol and of the formation of the Cl are not similar. This suggests that some chlorinated aliphatic species may be formed as possible intemediates.  相似文献   
88.
Concentrations of dissolved and particle-associated n-alkanes, phthalates and polycyclic aromatic hydrocarbons (PAHs) were measured in sea surface microlayer (SML) and sub-surface water (SSL) samples collected in the coastal area of Terra Nova Bay, Antarctica, during the Austral spring 1998/1999. SML concentrations of the selected organic compounds were higher than SSL values and the enrichment factors were greater in the particulate phase than in the dissolved phase. During the same campaign, "fresh" snow samples, collected at different altitudes (from sea level up to 2670 m) near the coast on Mt Melbourne, immediately after a snowy event, were analysed in order to provide more information on air/sea exchange processes. The same classes of organic compounds found in sea water were also present in "fresh" snow samples. The surfactant fluorescent organic matter (SFOM), adsorbed on the microdrop aerosol surface, could be considered the main constituent of the enrichment and the carrier at higher altitudes of organic compounds. In fact, hydrocarbons (n-alkanes and PAHs), which are not surfactants like phthalates, could interact with SFOM and follow the same fate.  相似文献   
89.
In this work we propose a Bayesian ecological analysis in which a latent variable summarizes data on emissions of atmospheric pollutants. We specified a hierarchical Bayesian model with spatially structured and unstructured random terms with a nested latent factor model. This can be considered a combination of the convolution spatial model of Besag et al. (1991) and an ecological regression analysis in which a latent variable plays the role of the covariate. The unified approach allows to proper account for the uncertainty in the latent score estimation in the regression analysis. The Bayesian Latent Factor model is used to summarize the information on environmental pressure derived from three stressors: Carbon Monoxide, Nitrogen Oxides and Inhalable Particles. We found evidence of positive correlation between Lung cancer mortality and environmental pressure indicators, in males, Tuscany (Italy), 1995–1999. Environmental pressure seems to be restricted to fourteen municipalities (top 5% of the Latent Factor distribution). The model identified two areas with high point source emissions.  相似文献   
90.
The principal aim of this research is to solve problems of water-budget estimation in particularly indeterminate conditions, of the kind that are frequently encountered in the field, in which absence or insufficiency of hydrographic instrumentation prevents the adequate evaluation of runoff.To do this we have developed techniques that are based on the method of Kennessey (1930), in which the runoff coefficient of a watershed in estimated using three physiographic variables (slope angle, permeability, and vegetation cover) and a parameter that defines the climatic conditions of the local area. Our comparison of the Kennessey method with instrumental records from a wide variety of instrumented drainage basins in central Italy shows that the method provides reliable estimates of runoff. Our analysis also indicates the best criteria for its application, as shown by the examples and results presented in this article.This research enables us to present a new application of the method, namely the runoff coefficient map, which, in addition to its specific usefulness for the evaluation of runoff, has three advantages. First, it supplies a more realistic vision of the local distribution of runoff/rainfall ratios; second, it allows one to overcome the spatial constraints imposed by the narrow frame of reference represented by the watershed; and third, it makes an important contribution to the solution of other hydrogeological problems, such as the evaluation of the amount of water required for adequate recharge of the intake areas of deep aquifers or the maintenance of geothermal processes.Hence we propose this mapping technique as a valuable practical aid to regional hydrogeologic planning.  相似文献   
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