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341.
BACKGROUND, AIM AND SCOPE: Electrocoagulation (EC) may be a potential answer to environmental problems dealing with water reuse and rational waste management. The aim of this research was to assess the feasibility of EC-process for industrial contaminated effluents from copper production, taking into consideration technical and economical factors. EC-technology claims to offer efficient removal rates for most types of wastewater impurities at low power consumption and without adding any precipitating agents. MATERIALS AND METHODS: Real wastewater from Saraka stream with high concentrations of heavy metals was provided by RTB-BOR, a Serbian copper mining and smelting complex. Runs were performed on a 10 l EC-reactor using aluminum plates as sacrificial electrodes and powered by a 40 A supply unit. Results concerning key factors like pH, conductivity and power consumption were measured in real time. Analysis of dissolved metal concentrations before and after treatment were carried out via ICP-OES and confirmed by an independent test via AAS. RESULTS: Several aspects were taken into account, including current density, conductivity, interfacial resistivity and reactor settings throughout the runs, in order to analyze all possible factors playing a role in neutralization and metal removal in real industrial wastewater. DISCUSSION: Electrode configurations and their effects on energy demand were discussed and exemplified based on fundamentals of colloidal and physical chemistry. CONCLUSIONS: Based on experimental data and since no precipitating agents were applied, the EC-process proved to be not only feasible and environmentally-friendly, but also a cost-effective technology RECOMMENDATIONS AND PERSPECTIVES: The EC-technology provides strategic guidelines for further research and development of sustainable water management processes. However, additional test series concerning continuous operation must be still performed in order to get this concept ready for future large-scale applications.  相似文献   
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The antifungal potential of the pygidial gland secretion of the troglophilic ground beetle Laemostenus punctatus from a cave in Southeastern Serbia against cave-dwelling micromycetes, isolated from the same habitat, has been investigated. Eleven collected samples were analyzed and 32 isolates of cave-dwelling fungi were documented. A total of 14 fungal species were identified as members of the genera Aspergillus, Penicillium, Alternaria, Cladosporium, Rhizopus, Trichoderma, Arthrinium, Aureobasidium, Epicoccum, Talaromyces, and Fusarium. Five isolates were selected for testing the antifungal activity of the pygidial gland secretion: Talaromyces duclauxi, Aspergillus brunneouniseriatus, Penicillium sp., Rhizopus stolonifer, and Trichoderma viride. The microdilution method has been applied to detect minimal inhibitory concentrations (MICs) and minimal fungicidal concentrations (MFCs). The most sensitive isolate was Penicillium sp., while the other isolates demonstrated a high level of resistance to the tested agent. L. punctatus has developed a special mechanism of producing specific compounds that act synergistically within the secretion mixture, which are responsible for the antifungal action against pathogens from the cave. The results open opportunities for further research in the field of ground beetle defense against pathogens, which could have an important application in human medicine, in addition to the environmental impact, primarily.  相似文献   
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Summary Croatia, as a Mediterranean country in the south-eastern part of Europe, is an area with a characteristic flora and fauna. The ornithofauna of Croatia reflects that it is a breeding area for some of the globally endangered bird species, as well as a site for the spring/autumn passage and the wintering of European migratory birds. Many ornithologically significant localities are designated and there are 20 ornithological reserves and four wetland sites that are on the list of the Ramsar Convention.In Croatia, there are four governmental organizations dealing with scientific research on birds of which the Institute for Ornithology of the Croatian Academy, of Sciences and Arts is that with the longest tradition. There are also many non-governmental organizations dedicated to the protection of environment, but only the Croatian Society for Bird and Nature Protection is dedicated mostly to bird protection. There are not many sources of funding for research and the protection of birds; the chief source being the Ministry of Sciences and Technology of the Republic of Croatia.Croatia has to establish new legislation according to European criteria and The Hunting Law, The Nature Protection Law and The Environment Protection Law have been recently accepted in Parliament. International Conventions, such as Bern, Bonn and Washington, have yet to be adopted. Foreign, hunting tourism, especially organized by fishpond authorities, is believed to be killing large numbers of protected water birds. A red data book exists only for plants and mammals and this makes biological assessments difficult.With the end of military operations and the reintegration of the occupied areas of Croatia, an assessment of the damage to the national parks and nature reserves, and to nature in general, will be necessary. Bird and nature conservation in Croatia remains promising, provided the legal control of the Croatian government over the occupied parts of the country is restored soon and international organizations give assistance.Dr Jasmina Muini is Croatian by birth and she has studied in Paris, Oslo, and Zagred where she gained her PhD. She is a President of the Croatian Society for Bird and Nature Protection, a member of the Croatian Parliament Board for Environmental Protection, vice-president of the Scientific Council of the Zoological Garden in Zagreb, and a member of other Croatian environmental bodies. She is a leading authority on the ornithofauna of the Croatian wetlands.  相似文献   
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We report a new case of prenatal diagnosis of recessive microcephaly by ultrasound examination allowing termination of pregnancy at 25 weeks gestation.  相似文献   
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This paper reviews and analyzes more than 400 scenarios of global and regional greenhouse gas emissions and their main driving forces - population, economy, energy intensity, and carbon intensity - drawn from an extensive literature survey and summarized in a database. This new and growing database is available online, which makes summary statistics on these scenarios widely available. The scenarios in the database were collected from almost 200 different literature sources and other scenario evaluation activities. The ultimate objective of the database is to include all relevant global and regional emissions scenarios. This paper shows how the database can be utilized for the analysis of greenhouse gas emissions ranges across the scenarios in the literature and for the analysis of their main driving forces. The scenarios in the database display a large range of future greenhouse gas emissions. Part of the range can be attributed to the different methods and models used to formulate the scenarios, which include simple spreadsheet models, macroeconomic models and systems-engineering models. However, most of the range is due to differences in the input assumptions for the scenarios, in particular of the main scenario driving forces. Special emphasis is given to an analysis of medians and ranges of scenario distributions and the distributions of the main scenario driving forces in the database. The analysis shows that the range for projected population increase in the world, across the scenarios in the database, is the smallest of all main driving forces (about a factor of 3 in 2100). The range of economic growth, measured by the gross world product, and the range of primary energy consumption vary by a factor of 10 in 2100. Carbon intensity of energy, an indicator of the degree of technological change, varies by nearly two orders of magnitude in the year 2100. In addition, this paper presents the first attempt to analyze the relationships among the main scenario driving forces. Subsequent papers in this special issue give further analyses of the relationships among the main scenario driving forces and their other relevant characteristics.  相似文献   
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