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Environmental insurance policies and the success of claims brought under them depend upon the intersection of both the legal and technical issues involved. The evolution of environmental insurance policies, from their origin in the Commercial General Liability policies up to the creation of new insurance products designed to cover specifically environmental concerns are addressed in this work. Both scientists and attorneys will have to develop a fuller understanding of environmental damage and assessments. The intent of this article is to provide a starting point for members of both disciplines in their quest for a fuller understanding of the legal and technical issues involved in environmental claims.  相似文献   
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An Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopic method was used to measure organic functional groups and inorganic ions at Tonto National Monument (TNM), an Interagency Monitoring of Protected Visual Environments (IMPROVE) sampling site in a rural area near Phoenix, Arizona. Functional groups and ions from common aerosol compound classes such as aliphatic and aromatic CH, methylene, methyl, aldehydes/ketones, carboxylic acids, ammonium sulfate and nitrate as well as functional groups from difficult to measure compound classes such as esters/lactones, acid anhydrides, carbohydrate hydroxyl and ethers, amino acids, and amines were quantified. On average, ~33% of the PM1.0 mass was composed of organic aerosol. The average (standard deviation) composition of the organic aerosol at TNM was 34% (6%) biogenic functional groups, 21% (5%) oxygenated functional groups, 28% (7%) aliphatic hydrocarbon functional groups (aliphatic CH, methylene and methyl) and 17% (1%) aromatic hydrocarbon functional groups. Compositional analysis, functional group correlations, and back trajectories were used to identify three types of events with source signatures: primary biogenic-influenced, urban-influenced, and regional background. The biogenic-influenced event had high concentrations of amino acids and carbohydrate hydroxyl and ether, as well as aliphatic CH and aromatic CH functional groups and qualitatively high levels of silicate. The urban-influenced events had back trajectories traveling directly from the Phoenix area and high concentrations of hydrocarbons, oxygenated functional groups, and inorganic ions. This aerosol characterization suggests that both primary emissions in Phoenix and secondary formation of aerosols from Phoenix emissions had a major impact on the aerosol composition and concentration at TNM. The regional background source had low concentrations of all functional groups, but had higher concentrations of biogenic functional groups than the urban source.  相似文献   
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Waste management in the building industry in Hong Kong has become an important environmental issue. Particularly, an increasing amount of construction and demolition (C&D) waste is being disposed at landfill sites. In order to reduce waste generation and encourage reuse and recycling, the Hong Kong Government has implemented the Construction Waste Disposal Charging Scheme (CWDCS) to levy charges on C&D waste disposal to landfills. In order to provide information on the changes in reducing waste generation practice among construction participants in various work trades, a study was conducted after 3 years of implementation of the CWDCS via a structured questionnaire survey in the building industry in Hong Kong. The study result has revealed changes with work flows of the major trades as well as differentiating the levels of waste reduced. Three building projects in the public and private sectors were selected as case studies to demonstrate the changes in work flows and the reduction of waste achieved. The research findings reveal that a significant reduction of construction waste was achieved at the first 3 years (2006–2008) of CWDCS implementation. However, the reduction cannot be sustained. The major trades have been influenced to a certain extent by the implementation of the CWDCS. Slight improvement in waste management practices was observed, but reduction of construction waste in the wet-finishing and dry-finishing trades has undergone little improvement. Implementation of the CWDCS has not yet motivated subcontractors to change their methods of construction so as to reduce C&D waste.  相似文献   
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Although humans are a major mechanism for short and long distance seed dispersal, there is limited research testing clothing as a vector. The effect of different types of material (sports vs hiking socks), or different items of clothing (boots, socks, laces vs legs) or the same item (socks) worn in different places on seed composition were assessed in Kosciuszko National Park, Australia. Data was analyzed using Repeated Measures ANOVA, independent and paired t-tests, Multi-dimensional Scaling Ordinations and Analysis of Similarity. A total of 24,776 seeds from 70 taxa were collected from the 207 pieces of clothing sampled, with seed identified from 31 native and 19 non-native species. Socks worn off-track collected more native seeds while those worn on roadsides collected more non-native seeds. Sports socks collected a greater diversity of seeds and more native seeds than hiking socks. Boots, uncovered socks and laces collect more seeds than covered socks and laces, resulting in 17% fewer seeds collected when wearing trousers. With seeds from over 179 species (134 recognized weeds) collected on clothing in this, and nine other studies, it is clear that clothing contributes to unintended human mediated seed dispersal, including for many invasive species.  相似文献   
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A contaminated soil was collected in a field adjacent to a derelict As((III)) smelter in Reppel (Bocholt, Belgium). A single soil treatment (% by soil weight) based on either iron grit (SS, 1%), beringite (B, 5%), or iron grit (1%) + beringite (5%) (BSS) was applied. Untreated and treated Reppel soils and a control soil were placed in lysimeters inside a greenhouse and cropped annually. The efficiency of soil treatments in decreasing As and metals in exposure sources and restoring soil functions was assessed 6 years after the treatments commenced. Decreases in extractable Cd, Mn, Zn and As occurred in the BSS soil. Only BSS treatment reduced both As and metal concentrations in leachates. BSS treatment produced best growth of lettuce and cabbage, the highest shoot and pod yields for dwarf bean, the lowest As, Cd and Zn concentrations in plant tissues, and partly restored Rhizobium nodulation on bean roots. The epigeic earthworm (Dendrobaena octaedra) could only survive in the BSS soil. Depurated living worms from the BSS soil had Cd concentration similar to those in control worms, but higher As, Ca, Fe, and Zn concentrations. Based on physiologically based extraction test (PBET), As bioaccessibility was reduced from 12% (untreated soil) to 7.4% (BSS) and 3% (SS), but only the SS treatment decreased the bioaccessibility of Cd (-30%) and Pb (-35%). The range of chemical and biological indicators suggested that BSS amendment was the most effective treatment for restoration of normal soil functions 6 years after initial treatment of the Reppel soil.  相似文献   
317.
Summary. Tracer feeding studies with radioactively labeled pyrrolizidine alkaloids (PAs) were performed to attain experimental information about the specificity and mechanisms of uptake, metabolism and storage of PAs in the alkaloid sequestering ithomiine butterfly Mechanitis polymnia. Adult butterflies easily ingest the tracers offered dissolved in a saturated sugar solution. Feeding of [14C]rinderine (free base) confirmed that M. polymnia is well adapted to sequester and maintain PAs of the lycopsamine type. Approximately 80% of the ingested radioactivity can be recovered in methanol extracts of the butterflies over a period of at least 6 hours. Labeled rinderine is efficiently N-oxidized and transformed into a metabolite of still unknown structure. These two metabolites are formed in almost equal amounts and account for more than 90% of total radioactivity. After four hours the toxic free base is only detectable in traces. Radioactively labeled senecioylretronecine (free base), a PA that often accompanies PAs of the lycopsamine type in plants, is metabolized in a different manner. The toxic free base disappeared as fast as the tertiary rinderine, but the final products which accumulated in a stable ratio after 12 hours were mainly two polar metabolites of unknown structure; senecioylretronecine N-oxide accounts for less than 10% of total PAs. Labeled senecionine a macrocyclic PA, which never has been found in wild caught M. polymnia is only slowly N-oxidized. In females ca 50% of the ingested senecionine is still present as free base after 24 hours, whereas under the same conditions in males this percentage is only ca 20%. This difference in N-oxidation was the only significant sex-specific difference observed in various experiments. Larvae of M. polymnia which feed on Solanum tabacifolium, a plant that does not contain PAs, are able to sequester and partly N-oxidize labeled senecioylretronecine and senecionine. However, the storage is not very efficient; with the two tracers less than 5% of radioactivity remained in the bodies after 24 hours. Received 19 October 1999; accepted 24 November 1999  相似文献   
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This paper identifies three models of person-situation interaction in an effort to conceptually clarify and integrate previous research. Statistical criteria for each model are then developed and tested within one organizational setting. Results indicate partial support for each of the three interaction models, and suggest various improvements for person-situation interaction research.  相似文献   
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