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951.
对空气-乙炔火焰原子吸收法测铬(Cr)时共存元素对其测定结果的干扰进行研究。结果表明,当ρ(共存元素)/ρ(Cr)100时,Mg、Co、Al、V、Ni、Fe、Na、Ca对Cr测定有影响,而K、Mn、Zn、Mo、Pb、Si、Cu均不影响Cr的测定;当ρ(共存元素)/ρ(Cr)为10和30时,加入1%HNO_3和2%NH_4Cl可消除干扰;当ρ(共存元素)/ρ(Cr)30时,加入5%HCl和超过1%的NH_4Cl可消除干扰;5%HCl作为介质消除Cr测定干扰的效果要优于1%HNO_3介质。 相似文献
952.
Triolo L Binazzi A Cagnetti P Carconi P Correnti A De Luca E Di Bonito R Grandoni G Mastrantonio M Rosa S Schimberni M Uccelli R Zappa G 《Environmental monitoring and assessment》2008,140(1-3):191-209
In order to evaluate the impact of atmospheric pollutants emitted by the industrial settlement of Milazzo (Italy) on agriculture,
sulphur dioxide and ozone levels in air were monitored and the data were used to estimate yield losses of the most widespread
cultures. Trace element concentrations in crops and soils were also detected and metabolic profiles of soil microbial communities
were considered. Vibrio fischeri test was used to appraise airborne pollutant ecotoxicity and epidemiological studies on causes of death distribution were
carried out to characterize health state of people living in the area. All the sampling points were selected in farms on the
basis of a theoretical meteo-diffusive model of industrial air pollutants. Experimental SO2 and O3 values mainly exceeded the threshold established by Italian and EU regulations to protect vegetation and they correspond
to estimated significant crop losses. Conversely toxic element residues in soils and in agroalimentary products were generally
lower than the fixed values. SO2 and O3 concentrations, toxic element contents and ecotoxicity levels of airborne pollutants were not related only to industrial
site emissions, while the fluctuations on metabolic profiles of soil microbial communities seem to agree with the predicted
deposition of xenobiotic compounds from the industrial plants. The epidemiological study evidenced a better health state of
populations living in the investigated area than in the Messina province and the Sicily region but, inside the area, males
living in the municipalities closest to the industrial settlement exhibited a worst health state than those in the very far
ones. 相似文献
953.
Pierre-André Jouvet Philippe Michel Gilles Rotillon 《Environmental Modeling and Assessment》2010,15(1):1-11
We are interested in the impact of pollution permits on wages and profits. We analyze important consequences of introducing
a market of pollution permits. A fundamental issue concerns the initial allocation of such permits: should they be allocated
freely by grandfathering or be auctioned. The international symmetric case allows us to capture the essence of the problem
on income factor. We show that allocating permits to factors in proportion of their contribution to production leads to an
efficient (neoclassical) distribution. Considering the international asymmetric case, we show that a permit market does not
modify the competitive world equilibrium without permits when the total allocation is large enough. When it is not, if allocation
of permits is not proportional to the emissions in the world without permits, there is a reduction factor of emissions that
results from the equilibrium allocation of capital. 相似文献
954.
This paper looks at the interplay between human capital and innovation when climate and educational policies are implemented. Following recent empirical studies, human capital and general purpose research and development (R&D) are introduced in an integrated assessment model used to study the dynamics of climate change mitigation. Our results suggest that climate policy stimulates general purpose as well as clean R&D but reduces the incentive to invest in human capital formation. Both innovation and human capital have a scale effect, which increases pollution, as well as a technique effect, which saves emissions for each unit of output produced. While the energy-saving effect prevails when innovation increases, human capital is pollution-using, also because of the gross complementarity between the labor and energy input. When the role of human capital is the key input in the production of general purpose and energy knowledge is accounted for, the crowding-out of education induced by climate policy is mitigated, though not completely offset. By contrast, a policy mix that combines educational as well as climate objectives offsets the human capital crowding-out, at moderate and short-term costs. Over the long run, the policy mix leads to global welfare gains. 相似文献
955.
Peretyatko A Teissier S De Backer S Triest L 《Environmental monitoring and assessment》2012,184(3):1517-1531
Phytoplankton, zooplankton, submerged vegetation and main nutrients have been monitored in 48 eutrophic ponds from the Brussels
Capital Region (Belgium) between 2005 and 2008. Nine ponds have been biomanipulated in order to improve their ecological quality
and prevent the occurrence of noxious cyanobacterial blooms. The 4-year study of a large number of ponds allowed identification
of the factors having the strongest influence on phytoplankton growth. Continuous monitoring of the biomanipulated ponds allowed
the significance of changes caused by biomanipulation to be tested as well as the main reasons of biomanipulation successes
and failures to be elucidated. The main factors controlling phytoplankton in the ponds studied appeared to be grazing by large
cladocerans and inhibition of phytoplankton growth by submerged vegetation. Biomanipulation resulted in a significant decrease
in phytoplankton biomass in general and biomass of bloom-forming cyanobacteria in particular that were associated with a significant
increase in large Cladocera density and size. In six out of nine ponds biomanipulation resulted in the restoration of submerged
vegetation. The maintenance of the restored clearwater state in the biomanipulated ponds was strongly dependent on fish recolonisation
and nutrient level. In the absence of fish, the clearwater state could be maintained by submerged vegetation or large zooplankton
grazing alone. In case of fish recolonisation, restoration of extensive submerged vegetation could buffer, to a considerable
degree, the effect of fish except for ponds with high nutrient levels. 相似文献
956.
Lília Maria de Oliveira Philippe Maillard Éber José de Andrade Pinto 《Environmental monitoring and assessment》2016,188(6):333
Non-point source water pollution is a major problem in most parts of the world, but is also very difficult to quantify and control since it is not easily separated from point sources and can theoretically originate from the whole watershed. In this article, we evaluate the relationship between land use and land cover and four water pollution parameters in a watershed in Southeast Brazil. The four parameters are nitrate, total ammonia nitrogen, total phosphorous, and dissolved oxygen. To help concentrate on non-point source pollution, only data from the wet seasons of the time period (2001–2013) were analysed, based on the fact that precipitation causes runoff which is the main cause of diffuse pollution. The parameters measured were transformed into loads, which were in turn associated with an exclusive contribution area, so that every measuring station could be considered independent. Analyses were also performed on riparian zones of different widths to verify if the effect of the land cover on the water quality of the stream decreases with the increased distance. Pearson correlation coefficients indicate that urban areas and agriculture/pasture tend to worsen water quality (source). Conversely, forest and riparian areas have a reducing effect on pollution (sink). The best results were obtained for total ammonia nitrogen and dissolved oxygen using the whole exclusive contribution areas with determination coefficients better than R2≈0.8. Nitrate and total phosphorous did not produce valid models. We suspect that the transformation delay from total ammonia nitrogen to nitrate might be an important factor for the poor result for this parameter. For phosphorous, we think that the phosphorous sink in the bottom sediment might be the most limiting factor explaining the failure of our models. 相似文献
957.
958.
959.
Natacha Heutte Véronique André Catherine Dubos Arvis Valérie Bouchart Françoise Lemarié Patrick Legendre Edwige Votier Marie-Yolande Louis Stéphane Madelaine Virginie Séguin Stéphanie Gente Philippe Vérité David Garon 《Environmental monitoring and assessment》2017,189(1):31
Indoor air quality in health care facilities is a major public health concern, particularly for immunocompromised patients who may be exposed to microbiological contaminants such as molds, mycotoxins, endotoxins, and (1,3)-ß-D-glucans. Over 2 years, bioaerosols were collected on a monthly basis in a cancer treatment center (Centre F. Baclesse, Normandy, France), characterized from areas where there was no any particular air treatment. Results showed the complexity of mycoflora in bioaerosols with more than 100 fungal species identified. A list of major strains in hospital environments could be put forward due to the frequency, the concentration level, and/or the capacity to produce mycotoxins in vitro: Aspergillus fumigatus, Aspergillus melleus, Aspergillus niger, Aspergillus versicolor, Cladosporium herbarum, Purpureocillium lilacinum, and Penicillium brevicompactum. The mean levels of viable airborne fungal particles were less than 30.530 CFU per m3 of air and were correlated to the total number of 0.30 to 20 μm particles. Seasonal variations were observed with fungal particle peaks during the summer and autumn. Statistical analysis showed that airborne fungal particle levels depended on the relative humidity level which could be a useful indicator of fungal contamination. Finally, the exposure to airborne mycotoxins was very low (only 3 positive samples), and no mutagenic activity was found in bioaerosols. Nevertheless, some fungal strains such as Aspergillus versicolor or Penicillium brevicompactum showed toxigenic potential in vitro. 相似文献
960.
Caroline Hoyoux Magali Zbinden Sarah Samadi Françoise Gaill Philippe Compère 《Marine Biology》2009,156(12):2421-2439
Wood falls in the deep sea have recently become the focus of studies showing their importance as nutrients on the deep-sea
floor. In such environments, Crustaceans constitute numerically the second-largest group after Mollusks. Many questions have
arisen regarding their trophic role therein. A careful examination of the feeding appendages, gut contents, and gut lining
of Munidopsis
andamanica caught with wood falls revealed this species as a truly original detritivorous species using wood and the biofilm covering
it as two main food sources. Comparing individuals from other geographic areas from substrates not reported highlights the
galatheid crab as specialist of refractory substrates, especially vegetal remains. M.
andamanica also exhibits a resident gut microflora consisting of bacteria and fungi possibly involved in the digestion of wood fragments.
The results suggest that Crustaceans could be full-fledged actors in the food chains of sunken-wood ecosystems and that feeding
habits of some squat lobsters could be different than scavenging. 相似文献