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271.
Reinke  N.  Voßnacke  A.  Schütz  W.  Koch  M. K.  Unger  H. 《Water, Air, & Soil Pollution: Focus》2001,1(5-6):333-340
Sea salt particles are part ofmarine aerosols in the troposphere. A fraction ofthese particles is released by droplets generatedduring the bursting of bubbles at the ocean surface.Droplets result from fragmentation of film caps (filmdroplets) and the disintegration of water jets formedsubsequent to the bubble collapse (jet droplets).This release process is also of importance fortechnical applications and, consequently, simulationtools have been developed, which now may be used toquantify the contribution of these effects to marineaerosol generation. To calculate the amount of filmdroplets generated, it is necessary to determine thevolume of the film cap, which is a function of itsthickness and surface area. While surface areas ofsmall bubbles can be determined by an analyticalsolution of a simplified balance of forces, shapes oflarge non-spherical bubbles are calculatednumerically. The determination of the film thicknessis based on a resonance model for bubbleoscillations. For a detailed analysis of the jetdroplet generation, the bubble burst induced jetformation and disintegration is simulated numericallyusing a SOLA-MAC algorithm.  相似文献   
272.
What motives do companies have to make a voluntary contribution to the protection and conservation of ecosystems? Could an international market for protected area certificates (PACs)—issued for geographical areas managed in accordance with social and environmental best practices—boost private investment? What are the market opportunities and risks that influence private sector investment? These questions are evaluated based on semi-structured expert interviews conducted in 39 German companies. Triangulation is used for data analysis to combine the advantages of qualitative and quantitative methods. Qualitative interview results complemented with the exploratory factor analysis allow identifying five motives for private sector investment, of which three are key motives in the early stage of developing PACs: direct financial benefits; the social legitimacy of entrepreneurial business; and the corporate dependency on ecosystems. Opportunities for private companies arise from the high marketing potential of certificates, the international orientation of the PAC market, and the bundling of different ecosystem benefits. Identified risks include a lack of differentiation, additional costs, and green washing. Depending on the transparency of the certification scheme, companies are aware that PACs could both improve and damage their credibility and reputation.  相似文献   
273.
Abstract

Objective: A number of studies have already grouped cyclists according to different aspects of their mobility behavior. This could be used e.g., to improve the bicycle infrastructure planning, to detect critical spots and, to reduce obstacles for cycling. This wide, preexisting, range of cyclist typologies usually concentrates on one or two influence factors and differs, content-wise, in both factors used, as well as, methodically. Based on existing cyclist typologies we extracted all possible influence factors to integrate them in one single questionnaire. The objective of this study, using an empirical, based approach, is to compare this typology of cyclists with existing ones, integrating all known influence factors of recent studies.

Methods: To address these issues, we conducted a Germany-wide online survey on cycling behavior, covering all relevant aspects we derived from both literature and especially, former cyclist typology studies including: social factors; the impact of environmental, individual; and route factors; as well as motives. The main goal was to identify distinct types of cyclists, and describe them as detailed as possible. The heterogeneous sample included a total of 10,294 responses.

Results: Using factor and cluster analyses, a multidimensional typology with four groups of cyclists was derived which were interpreted as: ambitious, functional, pragmatic, and passionate cyclists. In addition, socio-economic factors, cyclist’s motivation, and crash history were analyzed.

Conclusion: The results produced by grouping different characteristics of cyclists can lead to policy recommendations or communal bicycle traffic planning. Policy planners can estimate reactions of the different types on interventions and adjust their decisions which can serve to support already passionate cyclists or, encourage normally under-represented infrequent cyclists to cycle more. The extent of perceived safety plays here an important role in the classification, e.g., the handling of high-risk areas for crashes.  相似文献   
274.
While it is developing rapidly throughout Germany, bioenergy provision is open to different development opportunities. To understand the cause–effect relationships that drive bioenergy development and explore different development options and their effects on regional development, qualitative scenarios have been drafted using the Görlitz district as an example. The paper introduces the scenario method, with scenarios that are expressed in storylines. Driving forces and their relationships are thereupon reflected. The results show that the relation of the Common Agricultural Policy and Renewable Energy Act is of particular importance for future development in general. For the specific type of development in particular in rural regions, technologies are equally important, as they allow for both strongly central and highly decentralised developments. Due to an increasing diversity of options, the decision between central and decentral developments is, however, less technologically determined, but rather dependent on stakeholders’ decisions. Such stakeholders not only include stakeholders from the production sector, but also include consumers and affected parties, particularly the inhabitants whose living environment is changing rapidly. Both the landscape and society are subject to change. As a major driving force and an impacted system under change itself, social constellations must be taken into account to ensure a sustainable development under the signs of renewable energy expansion. Management tools should consider the interlinkage between landscape, energy, and social systems.  相似文献   
275.
A plant selection system based on the phosphomannose isomerase gene (pmi) as a selectable marker is often used to avoid selection using antibiotic resistance. Nevertheless, pmi gene is endogenous in several plant species and therefore difficult to use in such cases. Here we evaluated and compared Agrobacterium-mediated transformation of Linum usitatissimum breeding line AGT-952 (without endogenous pmi gene) and Nicotiana tabacum var. WSC-38 (with endogenous pmi gene). Transformation was evaluated for vectors bearing transgenes that have the potential to be involved in improved phytoremediation of contaminated environment. Tobacco regenerants selection resulted in 6.8% transformation efficiency when using a medium supplemented with 30 g/L mannose with stepwise decrease of the sucrose concentration. Similar transformation efficiency (5.3%) was achieved in transformation of flax. Relatively low selection efficiency was achieved (12.5% and 34.8%, respectively). The final detection of efficient pmi selection was conducted using PCR and the non-endogenous genes; pmi transgene for flax and todC2 transgene for tobacco plants.  相似文献   
276.
Information about heavy metal concentrations in food products and their dietary intake are essential for assessing the health risk of local inhabitants. The main purposes of the present study were (1) to investigate the concentrations of Zn, Cu, Pb, and Cd in several vegetables and fruits cultivated in Baia Mare mining area (Romania); (2) to assess the human health risk associated with the ingestion of contaminated vegetables and fruits by calculating the daily intake rate (DIR) and the target hazard quotient (THQ); and (3) to establish some recommendations on human diet in order to assure an improvement in food safety. The concentration order of heavy metals in the analyzed vegetable and fruit samples was Zn?>?Cu?>?Pb?>?Cd. The results showed the heavy metals are more likely to accumulate in vegetables (10.8–630.6 mg/kg dw for Zn, 1.4–196.6 mg/kg dw for Cu, 0.2–155.7 mg/kg dw for Pb, and 0.03–6.61 mg/kg dw for Cd) than in fruits (4.9–55.9 mg/kg dw for Zn, 1.9–24.7 mg/kg dw for Cu, 0.04–8.82 mg/kg dw for Pb, and 0.01–0.81 mg/kg dw for Cd). Parsley, kohlrabi, and lettuce proved to be high heavy metal accumulators. By calculating DIR and THQ, the data indicated that consumption of parsley, kohlrabi, and lettuce from the area on a regular basis may pose high potential health risks to local inhabitants, especially in the area located close to non-ferrous metallurgical plants (Romplumb SA and Cuprom SA) and close to T?u?ii de Sus tailings ponds. The DIR for Zn (85.3–231.6 μg/day kg body weight) and Cu (25.0–44.6 μg/day kg body weight) were higher in rural areas, while for Pb (0.6–3.1 μg/day kg body weight) and Cd (0.22–0.82 μg/day kg body weight), the DIR were higher in urban areas, close to the non-ferrous metallurgical plants SC Romplumb SA and SC Cuprom SA. The THQ for Zn, Cu, Pb, and Cd was higher than 5 for <1, <1, 12, and 6 % of samples which indicates that those consumers may experience major health risks.  相似文献   
277.
Determining the performance of ecosystem services at the city or regional level cannot accurately take into account the fine differences between green or gray structures. The supply of regulating ecosystem services in, for instance, parks can differ as parks vary in their land cover composition. A comprehensive ecosystem service assessment approach also needs to reflect land use to consider the demands placed on ecosystem services, which are mostly neglected by current research yet important for urban planning. For instance, if a sealed surface is no longer used, it could be unsealed to improve ecosystem service supply. Because of these scientific shortcomings, this article argues for a conceptual framework for the non-monetary assessment of urban ecosystem services at the site scale. This paper introduces a standardized method for selecting representative sites and evaluating their supply of and demand on ecosystem services. The conceptual design is supplemented by examples of Salzburg, Austria.  相似文献   
278.
We present naturalist sightings of seabirds and marine mammals made during a research cruise with the IceAGE project off Iceland and the Faroe Islands during September 2011. Our findings from the obtained pelagic database are in-line with many other, more in-depth studies, showing major declines for pelagic seabirds and likely sea mammals, thus revising the role that Iceland now plays for such species. Northern Fulmar (Fulmarus glacialis) was the most recorded species, followed by different gulls, Black-legged Kittiwake (Rissa tridactyla) and Northern Gannet (Morus bassanus). However, Atlantic Puffin (Fratercula arctica) and Common Murre (Uria aalge) were only seen very rarely, and no observations were made of Dovekie (Alle alle) or Thick-billed Murre (U. lomvia). These observations were surprising since Iceland is known, so far, to host globally relevant populations of these auk species. A surprising high number of thirteen species of passerines were also detected offshore, mostly Wheatear (Oenanthe oenanthe), Meadow Pipit (Anthus pratensis) and Reed Bunting (Emberiza schoeniclus). Only a few marine mammals (Balaenoptera and Megaptera sp.) were encountered. Our detections present underestimates but are discussed in relation to ongoing and recently reported but dramatic anthropogenic changes of Iceland and in the North Atlantic overall. These include the substantial decrease in bird populations, overfishing and subsequent trophic cascades, as well as climate change, Arctic shipping and more industrial development to come. In light of these dramatic ecological changes, we conclude with an urgent request for an improved effective conservation management for Iceland, the North Atlantic and its stakeholders for directly related global governance to handle problems proactively.  相似文献   
279.
Environmental Science and Pollution Research - In situ burning (ISB) is discussed to be one of the most suitable response strategies to combat oil spills in extreme conditions. After burning, a...  相似文献   
280.
The study focuses on individual and standard visual display unit (VDU) workplaces with respect to performance and muscular load. Three different work settings were realized: The workplace was either adjusted to individual preferences or to the European standard. The third condition mirrored exactly the individual setting, however participants were told that it was set according to another standard. Dependent variables were visual performance in a search task, the rated muscular load, and individual preferences. Results show that both individual work settings yielded a superior performance as compared to the standard. However, performance and muscular comfort improved when participants knew they had adjusted the workplace. Apparently, VDU users follow a intuitive rationale adjusting their work setting minimizing muscular load and optimizing performance.  相似文献   
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