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201.
Paul Harvey 《Disasters》1998,22(3):200-217
The paper examines the challenge of rehabilitation from complex political emergencies (CPEs) and identifies a strategy that is characterised as a civil society rebuilding approach. It focuses on Somalia and a case study of a CARE project that aims to build the capacity of local NGOs. The paper argues that civil society in CPEs is simultaneously being undermined and contested by warring parties and emerging after state collapse. The scope of the paper is limited to one case study and that case study examines only a single aspect of civil society: national and international NGOs. The paper therefore presents tentative and preliminary results based on limited research. However, in reviewing the literature and presenting a way of approaching the subject, it aims to suggest a starting-point for developing a theoretical framework for such research. The paper finds that international agencies have tended to focus on civil society institutions simply as conduits for aid money and that this has tended to create organisations which lack downward accountability, are dependent on donors and are not addressing the wider roles for civil society envisaged in the approach. Rebuilding civil society does hold out the promise of giving non-military interests a stronger voice and starting a process of changing the aid delivery culture. Achieving these objectives, however, will be a slow and largely indigenous process and there is a need for lowered expectations about what outside assistance can achieve 相似文献
202.
203.
204.
Ben Daley 《Sustainable Development》2009,17(4):210-219
Several authoritative studies indicate that air transport makes a strong, positive contribution to economic development – a contribution that far outweighs the environmental and social costs of aviation. This article investigates this benign view, analysing the assumptions upon which it is based and arguing that the relationship between air transport and economic benefits may be more complex than is commonly held. In particular, the benefits of air transport services may be highly unevenly distributed, with particular groups benefiting from air transport provision to a far greater extent than others. Hence this article poses the question of whether air transport is an effective tool for sustainable development, or whether it simply reinforces existing patterns of economic interest and political hegemony. Based on analysis of a range of key documents, some criteria are presented that could potentially be used to indicate how air transport may most effectively be used to promote sustainable development. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. 相似文献
205.
The present work attempts to address the main aspects of chronic and extreme risks in contemporary Athens. It focuses on two cases of acute chronic risk bedevilling the capital region, namely road accidents and noise pollution, and one case of extreme risk, namely seismic disasters. In all cases social vulnerability, seen as the attribute of social and economic entities that can serve to increase damage from given danger, is a basic determinant of risk level. This social vulnerability might be defined in terms of three constituent elements: exposure to, resistance against and resilience to danger impacts. The whole analysis seeks the generating causes of the relevant high risk levels; their distribution across the geographical and social space of the capital region; their impacts on citizens' lifestyle and awareness of unsustainability; the public policy actions to abate or mitigate them and the individuals' adaptive reactions or efforts to escape risks and finally the repercussions of individualized and governmental responses on future risk and vulnerability levels. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. 相似文献
206.
本文介绍了一种新型正压空气呼吸器面罩的结构设计。分别从数据采集、曲面重构及实体建模等方面对面罩的数字化设计步骤进行了详细阐述,并对面罩视野进行了初步校核。 相似文献
207.
/ A number of strategies for the control of vehicular emissions are being considered by the Philippine government to address Metropolitan Manila's air quality problem. An analytical tool is needed for optimizing criteria pollutant reductions given the budgetary constraints. The simplest approach is to take costs and pollutant removals to be linear with each strategy's scale of activity, and this is readily solved as a linear programming problem. Another approach is to use a dynamic system of weights which shift with progressive improvements in pollutant emissions. The two approaches yield somewhat different results, suggesting the sensitivity of the solution to the assumed weights. The study also illustrates the importance of a sound methodology for evaluating priorities given to different air quality goals. One such methodology may involve a polling of expert panels and the public to gain insight into the relative importance given to competing emissions reduction goals. An informal polling of resource agency staff was conducted and discussed in this paper. The authors take the position that proper planning involves tracing intermediate steps to the final outcome and not just focusing on the latter.KEY WORDS: Vehicular emissions; Urban air quality; Emissions control; Optimization; Manila; Environmental systems analysis 相似文献
208.
The quality of the waters collected from R. Arno was examined in the period September 1988 to December 1989. A first campaign in September/October 1988, during a period of low water, gives a general picture of pollution conditions along the river from the source to the mouth. the river appears to be heavily polluted immediately downstream of Florence and in the area of the textile industry.
In the second campaign, through the whole year 1989, particular attention has been given to the Florence area; the most significant results, compared with those from a previous investigation carried out in 1971, show only a small reduction of the pollution load, due to the shortage and inadequacy of wastewater depuration. Some considerations are reported on pollution drop with full spate. 相似文献
In the second campaign, through the whole year 1989, particular attention has been given to the Florence area; the most significant results, compared with those from a previous investigation carried out in 1971, show only a small reduction of the pollution load, due to the shortage and inadequacy of wastewater depuration. Some considerations are reported on pollution drop with full spate. 相似文献
209.
《Advanced Sustainable Systems》2017,1(6)
Electrocatalysts for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) are crucial for water splitting and fuel cells/metal–air batteries, of which the benchmark catalysts for HER/ORR and OER are expensive and scarce Pt‐based and Ir/Ru‐based compounds, respectively. In spite of this, no trifunctional electrocatalyst for HER, OER, and ORR with an acceptable performance have been reported. In response, herein, as a proof‐of‐concept experiment, this study first in situ couples element abundant FeM (M = Ni, Co) particles with the nitrogen‐doped porous carbon (NPC) by a facile and scalable strategy. Unexpectedly, the resulted FeM/NPC exhibits superior trifunctional catalytic activities for HER, OER, and ORR even in the same electrolyte, which can be attributed to the synergistic advantages of FeM/NPC in terms of its good conductivity, highly porous structure, high Brunauer−Emmett−Teller (BET) surface area, nitrogen doping, and the intimate contact of FeM and NPC. Furthermore, such trifunctional catalyst makes the overall water splitting work at moderate overpotential, and endows the assembled Zn−air battery with a good performance and impressive capacity to self‐power the overall water splitting, demonstrating its feasibility for practical application. 相似文献
210.
Ana Catarina T. Silva Pedro T. B. S. Branco Patricia Ferrini Rodrigues Sofia I. V. Sousa 《Sustainable Development》2023,31(2):959-975
Due to the COVID-19 pandemic, governments imposed several mobility restrictions which can be used to evaluate their impact on air quality and generate better-targeted policies to improve it. Therefore, this study aimed to define sustainable mitigation measures to reduce air pollution based on quantifying the impacts of the restrictions imposed during the COVID-19 pandemic on air quality in Portugal. Thus, hourly concentrations of PM10, PM2.5, NO2, O3, CO and SO2 were obtained from the Portuguese Air Quality Monitoring Network. Data was then divided into six periods (2020–2021) and compared with the corresponding historical periods (2015–2019). Furthermore, the satellite data of NO2, CO, and absorbing aerosol index (AAI) from the sentinel-5P TROPOMI was collected to complement the analysis conducted for the monitoring data. Overall, air quality improved in all study periods and areas, except in industrial sites. The satellite data corroborated the results herein achieved and thus validated the real effect of the measures adopted in the country during the pandemic on air quality. Sustainable policies to improve air quality could include remote (or hybrid) work whenever possible as a long-term measure and prohibition of travelling between municipalities when an extraordinary event of high air pollution is predicted or occurs. Other policies should be adopted for industrial areas. Given this, and as the restrictive mobility measures had a strong effect on reducing air pollution, the post-COVID era represents an opportunity for society to rethink future mobility and other emerging policies, that should favour softer and cleaner means of transportation. 相似文献