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Earlier assessments have suggested that salmon farms may act as a source of mercury (Hg) and other elements in local marine environments. In this study, we measured 30 elements in the livers of demersal Atlantic cod (Gadus morhua) and pelagic saithe (Pollachius virens) caught in association with salmon farms (farm associated [FA]; n = 75) or at reference locations (control; n = 80) in three regions throughout the latitudinal extent of Norway (59-70° N). Concentrations of most elements (24 of 30) were higher (20-70%) in cod compared to saithe. In particular, Hg was 6.8 times higher in cod than saithe. Nine elements were significantly different between FA saithe and control saithe, but only four (Hg, U, Cr and Mn) were highest in FA saithe, and this pattern was only detected consistently across all locations for Hg. Thirteen elements differed in concentration between FA cod and control cod, but only three elements (U, Al and Ba) were higher in FA cod than controls, and this pattern was only detected consistently across all locations for Al. After controlling for a set of potentially confounding variables, the estimated concentrations of Hg in saithe livers were ~80% higher in FA fish compared to controls. In contrast, Hg concentrations were ~40% higher in control cod compared to FA cod. Our results do not support the notion that salmon farms in general increase the concentrations of potentially harmful elements in wild fish, and the distribution of Hg and other elements in cod and saithe in Norwegian coastal waters may be more influenced by habitat use, diet, geochemical conditions and water chemistry.  相似文献   
94.
This study describes the relations between different dimensions of leadership commitment, safety climate and attitudes toward change, and how these affect employee perceptions of safety during organizational change in a high risk environment. We collected data from a European national air navigation services provider during a volatile 3-year corporatization process that ended in the sudden collapse of a deliberate change implementation project. Surprisingly, despite visible signs of internal and external stress caused by the volatile and disruptive change process, we did not observe any change in the traditional safety metrics of incident and accident reporting during the study. The study is based on a large survey (n = 422) of individual attitudes and perceptions of safety climate, perception of leadership commitment to safety, attitudes to organizational change, and perception of safety. The data support the claim that perception of safety at least, in part, depends on individual perceptions of the leadership’s commitment to safety, and the safety climate in place at a given point in time. The model shows how employee perceptions of the leadership’s commitment to safety and safety climate are related to both attitudes toward change, and to perceived safety.  相似文献   
95.
The environment in which biology exists has dramatically changed during the last decades. Life was formed during billions of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation and the terrestrial magnetism. The existing organisms are created to function in harmony with these forces. However, in the late 19th century mankind introduced the use of electricity and during the very last decades, microwaves of the modern communication society spread around the world. Today one third of the world’s population is owner of the microwave-producing mobile phones. The question is: to what extent are living organisms affected by these ubiquitous radio frequency fields? Since 1988 our group has studied the effects upon the mammalian blood-brain barrier (BBB) by non-thermal radio frequency electromagnetic fields (RF-EMF). These have been revealed to cause significantly increased leakage of albumin through the BBB of exposed rats as compared to non-exposed animals—in a total series of about two thousand animals. One remarkable observation is the fact that the lowest energy levels give rise to the most pronounced albumin leakage. If mobile communication, even at extremely low energy levels, causes the users’ own albumin to leak out through the BBB, also other unwanted and toxic molecules in the blood, may leak into the brain tissue and concentrate in and damage the neurons and glial cells of the brain. In later studies we have shown that a 2-h exposure to GSM 915 MHz at non-thermal levels, gives rise to significant neuronal damage, seen 28 and 50 days after the exposure. In our continued research, the non-thermal effects (histology, memory functions) of long-term exposure for 13 months are studied as well as the effects of short term GSM 1,800 MHz upon gene expression. Most of our findings support that living organisms are affected by the non-thermal radio frequency fields. Studies from other laboratories in some cases find effects, while in other cases effects are not seen. Our conclusion is that all researchers involved in this field have the obligation to intensify this research in order to reduce, or avoid, the possible negative effects of the man made microwaves!  相似文献   
96.
Environmental performance measurements are an important component in strategies for achieving ecologically sustainable development. However, models and frameworks for performance measurement are primarily developed for business and may not be directly applicable to public organizations. This study aimed to contribute to the development of environmental performance measurement tools for public sector organizations by developing an appropriate framework. The study is based on a case study of the Swedish Rail Administration. The main method for data collection was focus group interviews. The proposed framework presents important features of an environmental performance measurement for the public sector and is illustrated by results from the case organization. The framework was constructed using the causal-chain framework pressure-state-response (PSR) and the management system management-by-objectives (MBO), respectively measuring and managing performance towards both strategic and operational objectives. An environmental management system serves as a toolbox, encompassing and coordinating the environmental objectives and the tools for performance measurement.  相似文献   
97.
This paper presents a qualitative analysis of the human factor concept, more specifically what it means and includes in everyday professional discourse. It is founded on 10 extensive interviews with professional investigators within the road, maritime and rail administration concerning their practical investigative work. General and specific results are generated of interview contributions using a pragmatic communicative approach and discourse analysis.Results show that human factors is an expression tied to individual professional experience, sparks dissatisfaction and demands specification due to recurring indexicality problems. It tends to be used for negative matters. The specific results, listing eight different meanings, indicate that there is no such thing as a professional usage of the human factor but a spectrum of meanings. The study concludes that the meanings of the human factor (a) always evolve in the dynamic process of producing and understanding language, (b) are context-dependent, and (c) emerge through talk, as one type of discourse. Contrary to ordinary conceptions, there is no simple matter as a human factor that may be used in a routine manner. A non-specific use of the notion may even obscure a course of events and prevent necessary investigation, for example, if the human factor simply replaces a factor such as ‘fatigue’. Although contemporary interdisciplinary research focuses peripheral factors, the idea of individual humans and their erroneous acts has survived – and lives – in the practical world of professional investigators. Empirically deduced meanings need to be continuously highlighted and problematised if theory is to approach everyday professional practice.  相似文献   
98.
Ocean acidification has emerged over the last two decades as one of the largest threats to marine organisms and ecosystems. However, most research efforts on ocean acidification have so far neglected management and related policy issues to focus instead on understanding its ecological and biogeochemical implications. This shortfall is addressed here with a systematic, international and critical review of management and policy options. In particular, we investigate the assumption that fighting acidification is mainly, but not only, about reducing CO2 emissions, and explore the leeway that this emerging problem may open in old environmental issues. We review nine types of management responses, initially grouped under four categories: preventing ocean acidification; strengthening ecosystem resilience; adapting human activities; and repairing damages. Connecting and comparing options leads to classifying them, in a qualitative way, according to their potential and feasibility. While reducing CO2 emissions is confirmed as the key action that must be taken against acidification, some of the other options appear to have the potential to buy time, e.g. by relieving the pressure of other stressors, and help marine life face unavoidable acidification. Although the existing legal basis to take action shows few gaps, policy challenges are significant: tackling them will mean succeeding in various areas of environmental management where we failed to a large extent so far.  相似文献   
99.
Two visitor-monitoring methods, video monitoring and counts by human observers, were compared in order to identify and evaluate their respective advantages and disadvantages. The analysis considered user numbers, user type (walkers, dog walkers, bicyclists, and joggers) and group size of visitors. Remarkable differences were found between the two methods for user type and use levels. At low use levels, evaluations based on video monitoring resulted in fewer single bicyclists compared to counts by human observers, whereas at high use levels, human observers counted fewer walkers and bikers than video-interpreters. Based on this comparative analysis, we derive recommendations for more effective visitor-monitoring approaches. All data were collected during a visitor-monitoring project in the Danube Floodplains National Park in Austria between 1998 and 1999.  相似文献   
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