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901.
Abstract

In recent years there has been increasing interest in the use of so‐called ‘economic instruments’ in environmental policy. Economic instruments influence the behaviour of economic agents by providing financial incentives for environmentally improved behaviour, or disincentives for damaging behaviour. This paper explores the use of economic instruments in the field of sustainable community planning and development. It does so in the wider context of how environmental economic policy is made. The focus of this paper is to examine the role of policy instruments in community planning, and to review the different types of instruments that are available to policy‐makers. Numerous examples of the various instruments at the community level are described. It is widely believed that policy making should occur at the lowest or most local level possible while maintaining effectiveness. A system of government that does not give adequate legal power to local governments, and does not allow local governments considerable flexibility in the use of funds, cannot be expected to achieve all community objectives. Central governments must give local governments permission to take measures towards sustainable community planning, even though that requires giving them power to address broader issues. At the same time, when issues that should be addressed at national and international levels are not addressed, local governments may be able to take action individually. Given the general reluctance (and perhaps inability) of governments at all levels today to consider non‐economic and, particularly, non‐market policy instruments, it is pragmatic as well as timely to improve our understanding of economic instruments for sustainable community development.  相似文献   
902.
Acetaminophen (ACT), an analgesic and antipyretic substance, is one of the most commonly detected pharmaceutical compound in surface waters and wastewaters. In this study, fluidized-bed Fenton (FB-Fenton) was used to decompose ACT into its final degradation products. The 1.45-L cylindrical glass reactor had inlet, outlet and recirculating sections. SiO2 carrier particles were supported by glass beads with 2–4 mm in diameter. ACT concentration was determined by high performance liquid chromatography (HPLC). During the first 40 min of reaction, a fast initial ACT removal was observed and the “two-stage” ACT degradation conformed to a pseudo reaction kinetics. The effects of ferrous ion dosage and [Fe2+]/[H2O2] (FH ratio) were integrated into the derived pseudo second-order kinetic model. A reaction pathway was proposed based on the intermediates detected through SPME/GC–MS. The aromatic intermediates identified were hydroquinone, benzaldehydes and benzoic acids while the non-aromatic substances include alcohols, ketones, aldehydes and carboxylic acids. Rapid initial ACT degradation rate can be accomplished by high initial ferrous ion concentration and/or low FH ratio.  相似文献   
903.
One of the most important elements behind the success of Community‐based Therapeutic Care (CTC) programmes for the treatment of severe acute malnutrition has been their ability to achieve high levels of coverage. In CTC, coverage is measured using the Centric System Area Sampling (CSAS) method, which provides accurate and reliable estimates of programme coverage as well as information on the primary reasons for non‐attendance. Another important feature of CTC programmes is their use of socio‐cultural assessments to determine potential barriers to access and to develop context‐specific responses. By analysing data on non‐attendance provided by CSAS surveys, in conjunction with data from socio‐cultural assessments, it is possible to identify common factors responsible for failures in programme coverage. This paper focuses on an analysis of data from 12 CTC programmes across five African countries. It pinpoints three common factors (distance to sites, community awareness of the programme, and the way in which rejections are handled at the sites) that, together, account for approximately 75 per cent of non‐attendance.  相似文献   
904.
The Yellow River in transition   总被引:3,自引:0,他引:3  
Like many parts of the world, the Yellow River basin has problems associated with water scarcity, pollution, and flood risk. Analyses that focus only on the physical characteristics of these problems miss some of their most important social drivers. In this paper we identify some interlocking changes that have occurred as a consequence of economic reforms begun in China in 1978, and the implications of these changes for the Yellow River. The reforms have caused changes in the organisation of household production, increasing urbanisation and urban affluence, rapid industrialisation, and large scale spatial shifts in agricultural production. Rather than specific decisions it is these gradual changes that have affected the current status of the Yellow River and its basin. Our analysis suggests that at least some solutions to water problems in the Yellow River lie outside the basin, and beyond the realm of science or technology.  相似文献   
905.
The threat of sea-level rise and climate change means that coastal managers are being increasingly asked to make long-term assessments of potential coastal impacts and responses. In the UK, shoreline management planning (for flood and erosion hazards) and spatial planning now takes a 100 year perspective. An integrated framework across a wide range of physical and social issues is required for the assessment of coastal impacts and consequently for making sound management decisions. This paper provides an overview of the development of the ‘Tyndall Coastal Simulator’ including the underlying philosophy that is being followed. The Simulator is based on a series of linked climate models (CM) within a nested framework which recognises three spatial scales: (i) the global (GCM) scale; (ii) the regional scale and (iii) the Simulator Domain (a physiographic unit, such as a coastal sub-cell). Within the nesting, the larger scale provides the boundary conditions for the smaller scale. The models feed into each other and describe a range of relevant processes: sea level, tides, surges, waves, sediment transport and coastal morphology. Different climate scenarios, as well as the range of uncertainty, are being explored. Communication of results is a major issue and the Simulator includes a dedicated GIS-based user interface that allows a wide range of queries of model outputs. The paper demonstrates the possibility of developing an integrated framework that is multi-scale and capable of linking various models in order to simulate complex coastal processes and consequently allowing long-term assessments that are useful for setting future management plans.  相似文献   
906.
Participatory planning applied to water resources has sparked significant interest and debate during the last decade. Recognition that models play a significant role in the formulation and implementation of design and management strategies has encouraged the profession to consider how such models can be best implemented. Shared Vision Planning (SVP) is a disciplined planning approach that combines traditional water resources planning methodologies with innovations such as structured public participation and the use of collaborative modeling, resulting in a more complete understanding and an integrative decision support tool. This study reviews these three basic components of SVP and explains how they are incorporated into a unified planning approach. The successful application of SVP is explored in three studies involving planning challenges: the National Drought Study, the Lake Ontario‐St. Lawrence River Study, and the Apalachicola‐Chattahoochee‐Flint/Alabama‐Coosa‐Tallapoosa River Basin Study. The article concludes by summarizing the advantages and limitations of this planning approach.  相似文献   
907.
Agricultural development in the Murcia autonomous region, Spain, has led to overexploitation of groundwater resources, and climate change will further increase pressures. Policy options to tackle the current unsustainable situation include the development of inter-basin water transfer (IBWT) schemes from wetter regions in the north and the introduction of taxation to further control groundwater abstraction. Under these scenarios, farmers with current access to water could face higher water cost, whereas farmers in areas where water was previously not available could see first time availability of water resources. In this paper, we combine discrete choice-based interviews with farmers in the Torrealvilla catchment, in which they indicate how they would adapt their land use under different scenarios, with an input–output model to assess the aggregate effects of individual land use decisions on the economy and water consumption of the Murcia region. The paper presents steps taken in the development of an input–output table for Murcia, including disaggregation of the agricultural sector, accounting for sector water use and consideration of back- and forward linkages. We conclude that appropriate taxation can lead to better water use efficiency, but that this is delicate as relatively small changes in prices of agricultural products can have significant impacts on land use and water consumption. Although new IBWT schemes would enable water to be used more efficiently, they would considerably increase regional water consumption and the regional economy’s dependence on water. As this is not sustainable under future climate change, water saving development pathways need to be explored.  相似文献   
908.
Farming communities are increasingly expected to manage their agricultural activities in ways that ensure sustainable flows of a wide range of ecosystem services for society. The land use and management choices that farmers make are dependent upon their socio-economic characteristics and background, and in turn have important implications for the landscape and associated ecosystem services. Thus, a better understanding about the linkages between the characteristics of farmers, farm management and land use is important for managing multifunctional agro-ecosystems. In this paper, we first develop a typology of farmers for Torrealvilla catchment in Murcia, Spain, according to the characteristics of their households and farm management (e.g. the farmer’s age, household income, water access, land tenure and farm labour). This analysis distinguishes six types of farmers. Secondly, we analyse the link between farmer typology and the farmers’ responses to a number of scenarios. The scenarios describe different likely changes to agriculture in the catchment in terms of environmental constraints (irrigation water availability and rainfall pattern) and environmental policy regulation (water taxation and subsidies). This exercise enables us to explore the range of future land use changes that are likely to occur in the study area. The results indicate that: rain-fed agriculture is expected to experience gradual but extensive abandonment; vegetable/fruit farming and pig/animal rearing are likely to stagnate or even decline; and growing of grapes is likely to expand. Thirdly, we qualitatively evaluate how future land use changes are likely to affect key ecosystem services in the study area including future agricultural production and associated local income generation, erosion control, maintenance of the groundwater table and various cultural services associated with a heterogeneous agro-ecosystem. Particular changes such as expansion of grape production will increase food production and local income at the cost of further depletion of the aquifer and increased risk of salinisation. The outcomes of the study highlight that, to be effective, the design of agri-environmental schemes and other government interventions (e.g. specific compulsory regulations on farming practices and associated water use) should carefully take into account the characteristics of the farmers within the area of interest, their land uses and the possible diversity of responses to policy and environmental drivers. Opportunities exist for future studies quantifying the extent of the impacts of ecosystem service provision through formal models combining farmers’ land use decision-making and spatially explicit modelling of landscape processes.  相似文献   
909.
To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax.

A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn.  相似文献   
910.
The recognition that resilience is a critical aspect of infrastructure security has caused the national and homeland security communities to ask “How does one ensure infrastructure resilience?” Previous network resilience analysis methods have generally focused on either pre-disruption prevention investments or post-disruption recovery strategies. This paper expands on those methods by introducing a stochastic optimization model for designing network infrastructure resilience that simultaneously considers pre- and post-disruption activities. The model seeks investment–recovery combinations that minimize the overall cost to a distribution network across a set of disruption scenarios. A set of numerical experiments illustrates how changes to disruption scenarios probabilities affect the optimal resilient design investments.  相似文献   
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