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651.
The effect that sunlight has on the degradation rate of two model organic compounds, phenol and malic acid, by ozone is studied. The effect seems to be due to both direct light absorption (300-320 nm photons) by ozone, which produces the pollutant degradation, and light absorption by reaction intermediates. The presence of such a light notably improves the reactivity of ozone toward the organic species, leading to a faster and complete mineralization even at large initial total organic carbon values. The use of artificial sunlight (Xe lamp) is also explored. Finally, the simultaneous presence of sunlight and other ozone degradation catalyst like transition metal ions is studied, showing the beneficial effect of such a combination.  相似文献   
652.
Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the ‘WHO global polio eradication program’, is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.  相似文献   
653.
Landscape changes taking place from 1954 to 1992 in the muncipal district of Isernia city (Central Italy) were described in relation to a system of ecosystem classification. Isernia municipal district was selected for study because recent historic changes in this area represent a typical example of landscape transformation similar to many small cities of Italy and other Mediterranean countries. To assess overall changes, three land cover maps (scale 1:25,000) were derived from panchromatic aerial photographs and field surveys. These were then digitalised in a Geographic Information System. A Land Facet (LF) map was derived by combining a phytoclimatic, a lithostatigrafic and a topographic map, and then digitalised as data layers in the same GIS. Results demonstrated two main landscape transformation trends: forest and semi-natural areas increased (8%), whereas agricultural areas decreased (12%). The urban area was relatively small during the entire analysed period, growing from 1% in 1954, to just 5% in 1992. Forest coverage was significant on reliefs, on hillside ecosystems such as limestone and on clay and marl hills LF. Arable land was particularly significant in flat ecosystems with deeper soils, such as on recent alluvial plain LF. These temporal changes were interpreted as being related to the replacement of traditional farming methods (grazing pastures) with more intensive methods (crop fields), especially on alluvial plains.  相似文献   
654.
This study explores ecological vulnerability to land-use change in the U.S. Mid-Atlantic Region by spatially extrapolating land and economic development, and overlaying these projections with maps of sensitive ecological resources. As individual extrapolations have a high degree of uncertainty, five methods with different theoretical bases are employed. Confidence in projections is increased for counties targeted by two or more projection methods. A county is considered at risk if it currently supports three or more sensitive resources, and is projected to experience significant growth by the year 2010 by two or more methods. Analysis designated 19 counties and two cities as at risk, highlighting within a large region the priority areas where state and regional efforts would contribute the most to integrating environmental considerations into the process of land development. The study also found that potentially severe ecological effects of future land-use change are not limited to the outskirts of major urban areas. Recreational demands on smaller communities with mountain and coastal resources are also significant, as are initiatives to promote economic development in rural areas of high ecological quality. This approach provides a comprehensive overview of potential regional development, leading to an objective prioritization of high-risk areas. The intent is to inform local planning and decision-making so that regional and cumulative ecological degradation are minimized.  相似文献   
655.
A pilot-scale horizontal flow constructed wetland (HFCW) system planted with common reed (Phragmites sp.) was constructed to study how hydraulic loading rate (HLR), aspect ratio, water depth, and granular medium affect to the fate of several organic matter degradation intermediates namely, acetic acid (HAc), isovaleric acid (Isoval), and dimethylsulfide (DMS). ANOVA statistical analysis performed on the data set of 8 months of operation shows that the HLR and the water depth are two major factors that control the performance of HFCWs for the target analytes. A clear difference in the HFCW effluent concentrations was obtained according to water depth. Effluents of the shallow water depth contained lower DMS (1.05-1.44 microg l-1), HAc (7.91-10.9 mg l-1), and Isoval (0.11-0.15 mg l-1) concentrations than the deeper beds (DMS: 1.68-2.40 microg l-1; HAc: 9.29-14.4 mg l-1, and Isoval: 0.20-0.31 mg l-1). Such differences could be accounted to the different formation and consumption rates of the organic matter degradation intermediates, which is related with the redox potentials (E). Indeed, it could lead to different biochemical reactions of organic matter degradation according with the E value. HLR has a statistically significant influence on the effluent HAc, Isoval, and DMS concentrations. Seasonal variability of effluent HAc concentration shows that it is independent on the HAc loading. While the loading showed no seasonal pattern, the removal efficiency was clearly higher in cold months, which suggests a predominant internal production of HAc in HFCWs in the warm season from the accumulated organic particulate matter. Similar results were also found when Isoval and DMS were considered.  相似文献   
656.
The European Union Water Framework Directive requires the achievement of environmental objectives for the ecological quality of water bodies. A comparable implementation of the Directive throughout member countries of the European Union is necessary to verify equal protection of surface waters. The Directive specifies that member states determine ecological quality by means of biological indices. To improve comparability of water quality assessment, this research carried out an intercalibration trial between the Slovak Saprobic Index and the Italian protocol of the Extended Biotic Index, as part of a cooperative program between Italy and the Slovak Republic. When assessing streams with no or low pollution, statistics showed similar results for both methods. In contrast, the comparison of indices was not accurate in the case of severely affected waters. Reliable conversion formulas are feasible to transform the Italian Extended Biotic Index into the Slovak Saprobic Index, and not vice versa.  相似文献   
657.
Organizations that manage property that poses risks for surrounding communities need to practice stewardship. Stewardship is defined as carrying out the responsibility to manage land and facilities in a sustainable manner, while being accountable to others who have a stake in those resources. This article reviews six case studies of organizational stewardship and derives a set of five lessons learned, along with four challenges. Lessons include developing stewardship goals, good stakeholder relationships, multiple approaches to safety, and encouraging innovation and stable funding. Challenges include bureaucratic processes, burdensome regulations, organizational continuity, and inter‐organizational cooperation. These crosscutting lessons learned about how to achieve success or avoid failure in long‐term management of resources can be applied to all types of public and private agencies, including the long‐term management of environmental contamination. © 2003 Wiley Periodicals, Inc.  相似文献   
658.
The present longitudinal study explored the association between emotion regulation, defined as the conscious manipulation of one's public displays of emotion, and job satisfaction and intentions to quit. We predicted, based on an emotional dissonance model, that the suppression of unpleasant emotions decreases job satisfaction and increases intentions to quit. We propose a social interaction model that predicts that the amplification of pleasant emotions increases job satisfaction and decreases intentions to quit by improving the quality of interpersonal encounters at work. Data from 111 workers were gathered at two time points separated by four weeks. Advantages of the design included the use of longitudinal data and the statistical control for several personality, job, and demographic factors. Longitudinal regression analyses and tests of mediation revealed that, as predicted, (a) the suppression of unpleasant emotions decreases job satisfaction, which in turn increases intentions to quit, and (b) the amplification of pleasant emotions increases job satisfaction. Applied implications are discussed and suggestions for future research are offered. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
659.
Sustainability projects initiated by community groups can be significant in their contribution to the overall process of Local Agenda 21 planning and in their substantive contribution to sustainable communities. Community gardens differ from public gardens in that they are managed by community members rather than by local governments, although they may be located on council land. Community gardens vary in type from collections of individual plots to large-scale collaborative projects for the benefit of the wider community. Their roles include the production of fresh organic food; the creation of community places; and the use and dissemination of community science and innovative technologies. This paper reviews the types and roles of community gardens, and provides a case study of a community garden in Western Australia. It analyses the lessons learned from this particular case and the potential contribution of community gardens to Local Agenda 21 planning and to physical, ecological, sociocultural and economic sustainability.  相似文献   
660.
The distribution of three talitrid species—Talitrus saltator (Montagu, 1808), Orchestia gammarella (Pallas, 1766), Platorchestia platensis (Kroyer, 1845)—in the beach-dune system at the mouth of the Mignone River (central Italy) was analysed. It was related to the variations of the following abiotic factors: temperature, penetrability, pH, conductivity and moisture of the sediment. The beach-dune system is influenced by human impact and natural erosion. All species showed a maximum capture frequency in November, while the abundance decreased to a minimum in July. T. saltator was dominant on the beach, the other two along the riverbank. Juveniles were abundant along the riverbank; they were most abundant in November and almost disappeared in summer. T. saltator was more abundant near the waterline during the hottest months and occupied the inner beach in winter, with occasional presences on the dune. Regression analysis between the abiotic factors and species abundance showed a positive relationship with pH and temperature for T. saltator, while O. gammarella was negatively related to pH. Canonical correspondence analysis (CCA) showed that penetrability, moisture and temperature had the greatest influence on the species. T. saltator was almost entirely confined to the beach transects and strongly associated with penetrability, temperature and pH values. O. gammarella was mostly associated with the riverbank and P. platensis only found there and on a nearby pool. The two species were mainly influenced by moisture and variations in grain sizes of the sediment.  相似文献   
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