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441.
Species reintroduction efforts can improve the recovery of imperiled species, but successful implementation of this conservation strategy requires a thorough understanding of the abiotic and biotic factors influencing species viability. Species interactions are especially understudied, in particular by omitting the effect of imperfect detection on negative, neutral, or positive associations within a community. Using repeat surveys from 5 southern Ontario, Canada, Great Lakes tributaries, we quantified species co-occurrence patterns with the eastern sand darter (ESD) (Ammocrypta pellucida), listed as federally threatened, and characterized how imperfect detection during sampling can influence inference regarding these relationships. We used a probabilistic framework that included 3 approaches of increasing complexity: probabilistic co-occurrence analysis ignoring imperfect detection; single-species occupancy models with subsequent co-occurrence analysis; and 2-species occupancy models. We then used our occupancy models to predict suitable sites for potential future reintroduction efforts while considering the influence of negative species interactions. Based on the observed data, ESD showed several positive associations with co-occurring species; however, species associations differed when imperfect detection was considered. Specifically, a negative association between ESD and rosyface shiner (Notropis rubellus) was observed only after accounting for imperfect detection in the Grand River. Alternatively, positive associations in the Grand River between ESD and northern hogsucker (Hypentelium nigricans) and silver shiner (Notropis photogenis) were observed regardless of whether imperfect detection was accounted for. Our models predicted several potential reintroduction sites for ESD in formerly occupied watersheds with high levels of certainty. Overall, our results demonstrate the importance of investigating imperfect detection and species co-occurrence when planning reintroduction efforts.  相似文献   
442.
Remote sensing can advance the work of the Circumpolar Biodiversity Monitoring Program through monitoring of satellite-derived terrestrial and marine physical and ecological variables. Standardized data facilitate an unbiased comparison across variables and environments. Using MODIS standard products of land surface temperature, percent snow covered area, NDVI, EVI, phenology, burned area, marine chlorophyll, CDOM, sea surface temperature, and marine primary productivity, significant trends were observed in almost all variables between 2000 and 2017. Analysis of seasonal data revealed significant breakpoints in temporal trends. Within the terrestrial environment, data showed significant increasing trends in land surface temperature and NDVI. In the marine environment, significant increasing trends were detected in primary productivity. Significantly earlier onset of green up date was observed in bioclimate subzones C&E and longer end of growing season in B&E. Terrestrial and marine parameters showed similar rates of change with unidirectional change in terrestrial and significant directional and magnitude shifts in marine.  相似文献   
443.
Book reviews     
Deregulation in the European Union: environmental perspectives. U. Collier (Ed.), 1998, London, Routledge, ISBN 0 415 15694 7, £47.50 (hbk)

Protecting the European Environment: enforcing EC environmental law. H. Somsen (Ed.), 1996, London, Blackstone Press, ISBN 185 431 6044, £19.95

Green Parties and Politics in the European Union. Elizabeth Bomberg, 1998, London, Routledge, ISBN 0 415102 650, £15.99 (pbk)

British Environmental Policy and Europe. Philip Lowe & Stephen Ward (Eds), 1998, London, Routledge, ISBN 0 415155 010, £16.99 (pbk)

Wolf in the Garden: the land rights movement and the new environmental debate. Philip D. Brick & R. McGreggor Cawley (Eds), 1996, Lanham, MD, Rowman & Littlefield, ISBN 08476 8184 X, US$67.50 (hbk) ISBN 08476 8185 8, US$24.95 (pbk)

Fresh Water. E. C. Pielou, 1998, Chicago, IL, University of Chicago Press, ISBN 0 226 66815 0, US$24/£19.25 (hbk)

Environment and Politics. Timothy Doyle & Doug McEachern, 1998, London, Routledge, ISBN 0415 14776, £10.99

Eat Your Genes: how genetically modified food is entering our diet. S. Nottingham, 1998, London, Zed Books, ISBN 1 85649 577 9, £32.95 (hbk) ISBN 1 85649 578 7, £11.95 (pbk)

Working for Better Environmental Performance in SMEs. PACTE programme of the European Commission, 1997, Project of Berlin, Bristol, Copenhagen and Vienna1 (no charge)

Love Canal, the Story Continues. Lois Marie Gibbs, 1998, Gabriola Island, BC, New Society Publishers, ISBN 0 86571 382 0, US$16.95/Can$19.95 (pbk)  相似文献   
444.
445.
With increased affluence worldwide, planning for and preserving land for agriculture and conservation have become important goals in many communities. In Hawaii, the identification and designation of Important Agricultural Land (IAL) was first proposed at the 1978 Hawaii Constitutional Convention and approved by voters the same year. The state is required to conserve and protect agricultural lands, promote diversified agriculture, increase agricultural self-sufficiency, and assure the availability of agriculturally suitable lands. Act 183 in 2005 extended these efforts by defining IAL. The law established eight criteria to evaluate IAL and created county-led and landowner-initiated processes for designating IAL. It also specified policies for promoting agricultural production and identified landowner incentives for the designation of IAL. A central challenge facing policymakers is how to operationalize and implement these land use policies. This paper describes methods used to operationalize Act 183. We use fast feedback (i-Clicker technology) devices for capturing stakeholder preferences and geographic information systems and community mapping to visualize policy impacts and integrate community feedback. The methods developed in this paper have broad applications to jurisdictions around the world looking for data-driven approaches to planning and designating land uses according to legislative mandates or administrative requirements.  相似文献   
446.

Singlet oxygen (1O2), hydroxyl radicals (OH), and excited triplet states of organic matter (3OM*) play a key role in the degradation of pollutants in aquatic environments. The formation rates and quantum yields (Φ) of these reactive intermediates (RI) through photosensitized reactions of dissolved organic matter (DOM) have been reported in the literature for decades. Urban biowaste-derived substances (UW-BOS), a form of organic matter derived from vegetative and urban waste, have recently been shown to be efficient sensitizers in the photo-degradation of different contaminants. Nevertheless, no quantitative measurements of photo-oxidant generation by UW-BOS have been reported. In this study, the formation quantum yields of 1O2 and OH, as well as quantum yield coefficients of TMP degradation (indicative of 3OM* formation), were quantified for two UW-BOS samples, under 254-nm UV radiation or simulated sunlight and compared to a DOM standard from the Suwanee River (SRNOM). Values of Φ for UW-BOS samples ranged from Φ(+1O2) = 8.0 to 8.8 × 10−3, Φ(+OH) = 4.1 to 4.3 × 10−6, and f TMP = 1.22 to 1.23 × 102 L Einstein−1 under simulated sunlight and from Φ(+1O2) = 1.4 to 2.3 × 10−2, Φ(+OH) = 1.3 to 3.5 × 10−3, and f TMP = 3.3 to 3.9 × 102 L Einstein−1 under UV. Although UW-BOS are not necessarily better than natural DOM regarding photosensitizing properties, they do sensitize the production of RI and could potentially be used in engineered treatment systems.

  相似文献   
447.
Urea-formaldehyde resin bonded partlcleboard, medium density fiberboard and plywood paneling are used as flooring, wall paneling, for cabinet work and in furniture, and are present In almost every office, home and public building. If large quantities of these products are used In poorly ventilated spaces, high manufacturing quality control is necessary to avoid problems of latent formaldehyde release. Indoor air formaldehyde concentrations depend on the nature of the product, the product surface to air volume (loading) factor, temperature, humidity, age and product emission rates. Standard test methods are now available for measuring product emission rates that make It possible to predict the performance of UF-bonded pressed wood materials If use conditions and environmental parameters are known. Recent modifications In adhesive and board manufacturing parameters have made It possible to reduce formaldehyde emission significantly, and UF-bonded wood products are now capable of meeting indoor air quality standard levels of 0.1 ppm under almost all customary loading conditions.  相似文献   
448.
449.
Abstract

Based on exhaust gas analyses from the combustion of five different types of gasoline in a passenger car operated on a chassis dynamometer, box model simulations of the irradiation of exhaust/NOx /air mixtures using an established chemical mechanism for a standardized photo-smog scenario were performed. The fuel matrix used covered wide fractional ranges for paraffinic, olefinic, and aromatic hydrocarbons. Two fuels also contained methyl tertiary butyl ether (MTBE). The different O3 profiles calculated for each run were compared and interpreted. The O3 levels obtained were strongly influenced by the exhaust gas concentrations of aromatic and olefinic hydro-carbons. The higher exhaust content of these compounds caused higher O3 production in the smog system investigated. The conclusion of the present study is that the composition of gasoline cannot be taken directly for the estimation of the emissions’ O3 creation potential from its combustion. Variation of the dilution in the different calculations showed evidence for an additional influence of transport effects. Accordingly, further detailed exhaust gas analyses followed by more complex modeling studies are necessary for a proper characterization of the relationship between fuel blend and gasoline combustion products.  相似文献   
450.
Abstract

The feeding behavior of gypsy moth larvae exposed to two pesticide deposits (Bt and carbaryl) on oak leaf disks was monitored to determine the relationships between its efficacy and application parameters (droplet density and pesticide concentration). A range of pesticide concentrations and droplet densities (from 9 to 149 droplets/cm2) was used to simulate high and low application rates produced by different methods of application in the field.

The LD50 and the LC50, appeared to be affected by the spatial distribution of the deposit on the leaf surface. Both Bt and carbaryl showed a decreasing LD50 at increasing time after spray. The LD50 of Bt decreased from 14.1 BIU/liter to 3.1 BIU/Iiter between 48 and 144 hours after spray. The results show that feeding inhibition by Bt is more closely related to concentration than to droplet density and dose per unit area with the highest feeding inhibition occurring at 10 BIU/liter at 9 droplets/cm2. With carbaryl, an increase in both concentration and droplet density was necessary to cause a decrease in leaf area eaten by larvae.  相似文献   
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