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31.
In the new European Pesticide Regulation (EC) No. 1107/2009, the harmonisation of approaches for estimation of the environmental exposure of pesticides is considered a major goal. Several member states currently require their own models for the calculation of predicted environmental concentrations (PEC) in surface water. The variety of methods makes risk evaluations rather time-consuming for both notifiers and evaluating authorities. In the present study we compare surface water concentrations of 19 compounds using EU and country-specific models and risk assessment approaches to evaluate to which extent the resulting estimated exposure concentrations differ. Our results show that EU and country specific approaches and the resulting surface water concentrations differ considerably regarding basic model assumptions and assessment methods. The results indicate that the aimed harmonisation of risk assessment approaches within the EU will be difficult based on current models. New scenarios may help to achieve a harmonisation taking country-specific features into account.  相似文献   
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The article discusses the Norwegian version of the Swedish road safety concept Vision Zero, and how it has been interpreted and developed in its Norwegian context. Vision Zero has attracted considerable interest and support in many parts of the world, and it seems likely that the Vision Zero philosophy will continue to be a strong influence on international road safety work. It is not a given, however, that a vision will have the same kind of impact outside of the country and context where it was first developed. We briefly describe the official Norwegian documents of the vision, the main part of the article, however, is based on interviews with various actors in the Norwegian road safety system, in order to find how the vision is interpreted and perceived among those working with transport and road safety. Interviewees include politicians, representatives for the National Public Roads Administration, Council for Road Safety and Police, as well as NGOs. We find that the interpretative flexibility of the vision and relative lack of public debate have created a situation where actors focus on different aspects of the vision, and on different levels, from theoretical questions of ethics to specific practical questions of implementation. On the whole, it seems that the connection between the different levels of the vision are somewhat tenuous, and in this situation actors are relatively free to construct their own interpretation, rather than building one shared vision. While the modified Norwegian approach may very well prove effective, it nevertheless raises the question of what a “Vision Zero” approach means.  相似文献   
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Risk assessment of a chemical process plant requires the application of a variety of consequence models in order to estimate the potential physical effects of accidental releases. The types of models required vary depending upon the substance under consideration and the circumstances of a release. The objective of this study was the development and application of a system based upon ‘fuzzy logic’, for the selection of a computer model to be used in consequence analysis in specific situations where only certain types of consequence models can be used. The collection of data for modelling purposes from different kinds of computer model and application of fuzzy methods were also important aims of the study.  相似文献   
35.
Osteogenesis imperfecta (OI) is characterized by severe bone deformities, growth retardation and bones that break easily, often from little or no apparent cause. OI is a genetic disorder primarily with defective type I collagen with a wide spectrum of clinical expression. In the more severe cases, it can be diagnosed before birth. Transplantation of mesenchymal stem cells (MSC) has the potential to improve the bone structure and stability, growth and fracture healing. Prenatal and postnatal cell transplantation has been investigated in preclinical and clinical studies of OI and suggests that this procedure is safe and has positive effects. Cell transplantation resulted in improved linear growth, mobility and reduced fracture incidence. However, the effect is transient and for this reason re-transplantation may be needed. So far there is limited experience in this area, and proper studies are required to accurately determine if MSC transplantation is of clinical benefit in the treatment of OI. In this review, we summarize what is currently known in this field. © 2015 John Wiley & Sons, Ltd.  相似文献   
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Für die Anwendung der sequentiellen Schwermetallextraktion auf Proben, die nur im Milligramm-Bereich erhalten werden k?nnen (Mikroproben, wie z. B. Staubniederschl?ge), wurde die Methode vonZeien &Brümmer (1989) weiterentwickelt. Der Extraktionsma?stab wurde um den Faktor 1∶100 verringert und die Reproduzierbarkeit des Verfahrens mit variablen Probenmengen um 20mg und einem Extraktionsvolumen von 500 μl mit Hilfe von Standardb?den nachgewiesen. M?gliche Einflüsse variabler Extraktionsverh?ltnisse (Verh?ltnis von Probenmenge zu Extraktionsvolumen) sowie eine aufwendige Vorbehandlung von Staubproben, die nach der Bergerhoff-Methode (VDI 2119/2, 1972) gesammelt wurden, lagen bei diesen Untersuchungen weitgehend im Variationsbereich des Verfahrens. Die sequentielle Extraktion kann folglich zur Untersuchung der Mobilisierbarkeit von Schwermetallen auch aus Mikroproben mit variablen Probenmengen eingesetzt werden. Mit Hilfe dieses Verfahrens wurden die Mobilisierbarkeiten von Zink, Kupfer und Blei der Schluff- und Tonfraktion von Stra?ensedimenten mit Staubniederschl?gen an zwei urbanen Standorten mit unterschiedlicher, verkehrsbedingter Schwermetallbelastung verglichen. Diese Untersuchungen werden in Teil 2 (“Sequentielle Schwermetallextraktion von st?dtischen St?uben”) vorgestellt.  相似文献   
37.
Abstract: Data from several animal species and a few plant species indicate that small populations face an elevated risk of extinction. Plants are still underrepresented in these studies concerning the relation between population size and persistence. We studied the effect of population size on persistence among natural populations of the rare bellflower Campanula cervicaria in Finland. We monitored 52 bellflower populations for 8 years and found that the mean population size decreased from 24 to 14 during this period. Small populations with ≤5 individuals were more prone to losing all fertile plants than were larger ones. Reduction in population size was nevertheless unrelated to the degree of population isolation, measured as the distance to the nearest known population. To test the hypothesis that offspring fitness is lower in small populations, we germinated bellflower seeds from different-sized populations in a laboratory and found that seed germination ability was independent of population size. The seedlings raised from seeds of small populations grew faster than those taken from larger populations. Population size was negatively related to the amount of shade in the habitats. In conclusion, decreasing population sizes of C. cervicaria seemed not to be caused by lowered germination ability or growth rate in small populations; rather, population size reductions appeared to be due to closing of vegetation in the habitats.  相似文献   
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This article examines farmers’ livelihood responses and vulnerability to climate variability and other stressors in Morogoro, Tanzania, to understand their implications for adaptation to climate change by agricultural households in developing world more generally. In Morogoro, agricultural households have extended cultivation, intensified agriculture, diversified livelihoods and migrated to gain access to land, markets and employment as a response to climatic and other stressors. Some of these responses have depleted and degraded natural resources such as forest, soil and water resources, which will complicate their living with climate change in the future. This will be particularly problematic to vulnerable groups such as women, children and pastoralists who have limited access to employment, markets and public services. In this light, fair adaptation to climate change by agricultural households in Morogoro and elsewhere in developing countries requires several complementary responses. Adaptation efforts should involve effective governance of natural resources because they function as safety nets to vulnerable groups. In addition, strengthening of national markets by infrastructure investments and institutional reforms is needed to give incentives to intensification and diversification in agriculture. Market participation also demands enhancement of human capital by public programs on health, education and wellbeing.  相似文献   
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