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171.
Rodolfo Sousa Marcello Veiga Dirk Van Zyl Kevin Telmer Sam Spiegel Jeff Selder 《Journal of Cleaner Production》2011,19(6-7):742-750
In Brazil, artisanal and small-scale gold mining (ASGM) produces in the range of 6 tonnes of gold (Au) per annum, and employs approximately 200,000 people. Most of this mining activity is in the Amazon region, where miners have been extracting gold for more than 40 years. In the Tapajos River Basin, assessments indicate that around 99% of miners operate without the environmental and mining permits required by law. This is a result of a combination of unrealistic or lack of proper policies and regulations, lack of political will, lack of infra-structure to enforce the existing regulations and lack of incentives to miners to comply with legal requirements.In this article, we analyze a group of 20 laws, decrees and resolutions in Brazil, focusing on how idiosyncrasies in these regulations reveal gaps between policy and reality in ASGM areas. Artisanal miners operate in vast and remote areas and the government lacks the resources (personnel, vehicles, information and materials) to enforce the laws. Our analysis emphasizes the need for creating new government commitments and identifying priority areas where government agents can focus their efforts.There is no single solution for the environmental, health, technical and socio-economic problems associated with ASGM. However, a realistic approach should consider improving the level of education of miners, creating government programs to provide technical assistance in the field, simplifying administrative procedures and ensuring adequate measures for enforcement. 相似文献
172.
Much can be learned about adaptation by applying structures and methodologies already used in other research fields. This study employs a public economic policy approach to investigate how – or if at all – adaptation should be supported by the public sector. Three different fields of adaptation activity are identified which are especially relevant for government intervention and the study proposes ways in which government intervention could be conducted. The analysis takes into account that developing regions are particularly vulnerable and they have insufficient funds to adequately adapt to climate change. 相似文献
173.
Steffen Stubenrauch Reinhold Hempfling Peter Doetsch und Dirk Grünhoff 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(4):219-226
Zusammenfassung Um zu einer sachgerechten und nachvollziehbar quantifizierbaren Beurteilung der m?glichen Gesundheitsbelastungen des Menschen
durch Schadstoffe zu gelangen, ist es von grundlegender Bedeutung dessen ?u?ere Schadstoffexposition absch?tzen zu k?nnen.
Um die Durchführung derartiger Absch?tzungen zu erm?glichen, werden nutzergruppen- und expositionsszenariospezifisch orale,
inhalative und dermale Aufnahmeraten für die Kontaktmedien Boden, Pflanzen aus Haus- und Schreberg?rten, Trinkwasser, Staub,
Hausstaub und Innenraumluft vorgeschlagen. Diese Aufnahmeraten dienen, gemeinsam mit gemessenen oder berechneten Schadstoffkonzentrationen
in den entsprechenden Kontaktmedien, zur Absch?tzung der von Menschen aufgenommenen Schadstoffdosen und erm?glichen durch
einen Vergleich mit tolerierbaren Schadstoffdosen eine stoff-, nutzungs- und standortbezogene Beurteilung von Schadstoffexpositionen,
auch für komplexe Nutzungen.
相似文献
174.
Stefan Aerts Dirk Lips Stuart Spencer Eddy Decuypere Johan De Tavernier 《Journal of Agricultural and Environmental Ethics》2006,19(1):67-76
When making an assessment of animal welfare, it is important to take environmental (housing) or animal-based parameters into
account. An alternative approach is to focus on the behavior and appearance of the animal, without making actual measurements
or quantifying this. None of these tell the whole story. In this paper, we suggest that it is possible to find common ground
between these (seemingly) diametrically opposed positions and argue that this may be the way to deal with the complexity of
animal welfare. The model will have to be acceptable for the different parties that will be affected by it and real benefits
for the animal should result from it. This will be the basis of a practical ethical approach. All this can be condensed into
a model that essentially is made up out of three basic elements: the classical welfare analysis with an existing welfare assessment
tool, an assessment of the stockholder, and an implementation of the Free Choice Profiling technique. This new framework does
not pretend to be a different or better animal welfare matrix; it is intended to integrate existing knowledge and to provide
a practical tool to improve animal welfare. It identifies whether there are welfare problems on a farm, if present whether
these problems are caused by the housing system or the stockholder, and what can be done to improve the situation. 相似文献
175.
Gertrud Cremer-Bartels Kunibert Krause Georgios Mitoskas Dirk Brodersen 《Die Naturwissenschaften》1984,71(11):567-574
The influence of 50% decrease and increase of the earth magnetic field on the activity of the enzymes hydroxyindole-O-methyltransferase (HIOMT) and N-acetyl-serotonintransferase (NAT) is proved in vivo and in vitro. NAT and HIOMT catalyse the melatonin biosynthesis in the pineal gland and in the retina. Our results support the hypothesis of Leask and Schulten, that molecular magnetic field sensitivity is the basis of animals' magnetic field detection. 相似文献
176.
M. B. McEachern John M. Eadie Dirk H. Van Vuren 《Behavioral ecology and sociobiology》2007,61(9):1459-1469
We used DNA microsatellites to investigate temporal and spatial patterns of local genetic differentiation and relatedness
in a solitary mammal, the dusky-footed woodrat (Neotoma fuscipes). Patterns of genetic variation were measured relative to spatial clusters, or neighborhoods, of woodrats. We detected significant genetic differentiation among woodrat neighborhoods in two populations spanning multiple
habitat types and densities. Estimates of θ
ST
among neighborhoods ranged 0.034–0.075 and were comparable to levels reported in social mammals. Genetic differentiation
at such a local scale is noteworthy because it occurred in the absence of any physical barriers to gene flow, suggesting that
the patterns observed are linked to the nonrandom patterns of mating and dispersal that characterize woodrat social structure.
Genetic differentiation and relatedness among neighborhoods were even higher when only resident females were analyzed. These
results are consistent with a pattern of female philopatry and male-biased dispersal in woodrats. Geographic distance and
relatedness were inversely correlated in adult females at intermediate densities, but not at low densities. Nonetheless, matrilineal
genetic structure was apparent even at low woodrat densities based on estimates of θ
ST
among neighborhoods of resident females that were significantly greater than zero and consistently greater than estimates
including all individuals. In summary, this study demonstrates a matrilineal genetic structure in dusky-footed woodrats. In
addition, our results support the idea that intermediate densities may be better at facilitating the formation of spatial
kin clusters than either extreme.
An erratum to this article can be found at 相似文献
177.
178.
Insular Endemic Plants Lack Defenses Against Herbivores 总被引:3,自引:0,他引:3
179.
180.
This paper presents results of the assessment of the design parameters leading to the definition of the crest level of a coastal
dike along the German North Sea. Procedures to estimate the design water level have been proposed, distinguishing between
comparative and single value procedures. The transformation of the wave characteristics from deep water towards the shallow
foreshore was achieved through the application of a spectral wave model. To improve the wave parameter estimations, the existing
model was nested to a grid with a higher resolution closer to the coast. The estimation of the wave run-up followed the Dutch
procedure with some adjustments to the local wave characteristics and dike geometry. The computed maximum crest level of 8.4 m
is below the crest height of the existing dike, which is 8.8 m. However a proposal for a more economical design should be
carefully evaluated, paying attention to the uncertainties encountered in this research. The general recommendation is to
enhance the reliability of the hindcasted wave parameters through calibration and validation of the wave model and to include
in the design process an investigation of the effect of the medium term morphological developments. 相似文献