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91.
The paper presents a generic process synthesis and optimisation tool suitable to take up applications in the design of waste treatment systems and in pollution prevention. The main component of the technology is a generalized process synthesis representation for simultaneous consideration of reaction and separation in multiphase systems that is amenable for stochastic optimisation. The flexibility of the representation allows applications to overall process synthesis problems as well as to decomposed reactor, reactive separation and mass exchange network design problems. Applications of the synthesis framework to waste water treatments processes using activated sludge and to natural gas sweetening in hybrid membrane-adsorption processes are presented. The paper highlights the use of the systematic technology in environmental systems design and shows how novel designs of improved performance as well as optimal design knowledge can be revealed using the systematic design framework. Context abstract: Environmental process systems for waste treatment and pollution prevention become increasingly complicated to design. There is a strong need for technology that provides systematic decision support to the process synthesis team in order to enable the timely selection of processes that operate close to the performance limits of the system under consideration. Conventional, optimisation-based process design technology is severely limited by the number of design decisions they can support simultaneously as well as by the increasingly complex process models required for the meaningful mathematical representation of environmental process systems. We have devised an optimisation-based process design methodology for integrated reaction and separation systems that overcomes major limitations of existing tools. This paper illustrates the use of this technology to provide systematic decision-support to the environmental process systems designer.  相似文献   
92.
Climate change impacts on the hydrological cycle, e.g. leading to changes of precipitation patterns, have been observed over several decades. Higher water temperatures and changes in extremes hydrometeorological events (including floods and droughts) are likely to exacerbate different types of pressures on water resources with possible negative impacts on ecosystems and human health. In addition, sea-level rise is expected to extend areas of salinisation of groundwater and estuaries, resulting in a decrease of freshwater availability for humans and ecosystems in coastal areas. Furthermore, climate-related changes in water quantity and quality are expected to affect food availability, water access and utilisation, especially in arid and semi-arid areas, as well as the operation of water infrastructure (e.g. hydropower, flood defences, and irrigation systems). This paper serves as an introduction to the special issue of Environment Science & Policy dealing with climate change impacts on water-related disasters. It provides a brief background about relevant EU water policies and examples of EU-funded research trends which illustrate on-going efforts to improve understanding and modelling of climate changes related to the hydrological cycles at scales that are relevant to decision making (possibly linked to policy).  相似文献   
93.
Coastal areas are vital economic hubs in terms of settlement, industry, agriculture, trade and tourism to mention some key sectors. There are already many coastal problems including erosion, flood risk and long-term habitat deterioration. As economies continue to develop the asset base at risk will grow, while accelerating climate change will increase the likelihood of damaging extreme events, as well as accelerate habitat decline. Existing coastal management and defence approaches are not well tuned to these challenges as they assume a static situation.THESEUS project is developing a systematic approach to delivering both a low-risk coast for human use and healthy habitats for evolving coastal zones subject to multiple change factors. The project examines innovative mitigation and adaptation technologies and integrate the best of these technical measures in a strategic policy context through overarching guidelines. THESEUS activities are carried out within a multidisciplinary framework using 8 study sites across Europe, with specific attention to the most vulnerable coastal environments such as deltas, estuaries and wetlands, where many large cities and industrial areas are located.This paper describes THESEUS approach, and specifically: the Source-Pathway-Receptor-Consquence model for coastal risk assessment; the engineering, social, economic and ecological mitigation measures under analysis; the participatory approach with end users and coastal authorities for the selection and identification of the appropriate defence strategy to be planned in sudy sites.  相似文献   
94.
We report on a partial varanopid skull and mandible from the Pristerognathus Assemblage Zone of the Beaufort Group, in the South African Karoo Basin, which is probably latest Middle Permian (Capitanian) in age. This mycterosaurine is not only the youngest known varanopid from the Southern Hemisphere, but it is also the youngest known “pelycosaur” (i.e., non-therapsid synapsid). Like all other members of this clade of hypercarnivores, the teeth are strongly flattened, recurved, and have finely serrated cutting edges. The anterior dentary teeth form a caniniform region, and the splenial features a foramen intermandibularis oralis, the first ever to be described in a “pelycosaur.” The last varanopids were the smallest carnivores of latest Middle Permian continental faunas. Occupation of the small carnivore guild appears to have allowed varanopids to achieve a nearly cosmopolitan distribution throughout the Middle Permian, between the great Early Permian radiation of basal synapsids and the spectacular diversification of therapsid synapsids in the Late Permian and Early Triassic.  相似文献   
95.
Government interventions have been identified as important for energy systems change, because they can either facilitate or hinder transitions toward more sustainable energy systems. This article analyses how bioenergy options have been framed in Finnish policy strategies and how the framing has changed over time. The empirical material includes the content of 15 government programmes and nine national energy/climate strategies. On the basis of this assessment, both the link between bioenergy framings in strategies and the actual transformation of Finnish bioenergy systems are explored.On the basis of bioenergy framings, the development of energy policy can be divided into three phases: support for domestic energy sources in 1979-1991, support for wood- and industry-based bioenergy in 1992-1998, and diversified bioenergy in the context of climate change in 1999-2010. For two decades, primarily wood-based bioenergy was supported despite alternative technological developments occurring elsewhere. After the turn of the millennium, the importance of climate policy increased and alternative bioenergy sources were raised on the government policy agenda, also resulting in some new policy instruments. Rather than adopting a visionary outlook to guide system transformation, climate and energy policy has strengthened those technological options that have been selected elsewhere. If public policies are to enhance the shift toward low-carbon, sustainable energy systems, they would need to be more comprehensive, be more consistent over time, and emphasise energy use more.  相似文献   
96.
To study the effect of eating foods with a high arsenic (As) content on the intra and inter-individual variability of urinary concentrations of the As species, daily urine samples were collected for 10 consecutive days from 12 healthy male subjects. A daily food diary was kept throughout the study period. Personal exposure to airborne As was measured once during the study. As3, As5, monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine were determined in all urine samples by inductive coupled plasma mass spectrometry, and the sum of As3 + As5 + MMA + DMA (iAs) by hydride generation-atomic absorption spectrophotometry. Exposure to airborne As was below the limit of detection in all samplings. As3 was found in only 19.2% and As5 in only 3.3% of the urine samples, whereas high urinary concentrations of arsenobetaine were observed. With the exception of arsenobetaine, expressed as a percentage, a significant inter-individual variability was observed for all species of As, for iAs and for the MMA/DMA ratio (p < 0.001). Instead, the intra-individual variability was significant only for the MMA/DMA ratio (p < 0.001). Among foods with a high As content, only a heavy consumption of seafood was shown to influence inter-individual variability of DMA%, arsenobetaine expressed as μg g−1 creatinine and iAs. In conclusion, even in populations with a high intake of organic As through foods, the finding of a significant inter-individual but no significant intra-individual variability of urinary species confirms the usefulness of urinary As speciation for biological monitoring of exposure to As.  相似文献   
97.
98.

Problem

Safety culture relates to injuries and safety incidents in organizations, but is difficult to asses and measure. We describe a preliminary test of assessing an organization's safety culture by examining employee interpretations of organizational safety artifacts (safety signs).

Method

We collected data in three organizations using a new safety culture assessment tool that we label the Safety Artifact Interpretation (SAI) scale; we then crossed these data with safety climate and leadership evaluations.

Results

SAI were interpreted by employees in accordance with two conceptually distinct themes that are salient in the literature on organizational safety culture: safety compliance and commitment to safety. A significant correlation exists between SAI scores and the organizational safety climate. A similar (though insignificant) relationship was observed between SAI scores and leadership ratings.

Impact on industry

Employee perceptions and interpretations of safety artifacts can facilitate assessments of safety culture and can ultimately lead to understanding of and improvements in the level of organizational safety.  相似文献   
99.
100.
环境风险预警评估方法研究   总被引:1,自引:0,他引:1  
有毒有害物质发生突发性事故时将造成环境危害,使人体健康受到影响,严重时机毁人亡。本文通过对有毒有害污染源分析,事故频率分析,后果分析,风险预警估算及防范措施与应急计划的分析从环境风险与人体健康的角度上论述了在有毒有害物质作业场所预警技术问题。  相似文献   
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