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31.
Lesiv Myroslava Shvidenko Anatoly Schepaschenko Dmitry See Linda Fritz Steffen 《Mitigation and Adaptation Strategies for Global Change》2019,24(6):985-1006
Mitigation and Adaptation Strategies for Global Change - The spatial representation of forest cover and forest parameters is a prerequisite for undertaking a systems approach to the full and... 相似文献
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Numerous cases of hereditary diseases and disorders have been reported in wild animals bred in captivity, but little attention has been paid to the particular genetic management problems that arise when such defects occur. These problems include the obstacle of eliminating the deleterious allele(s) without contemporary loss of genetic variability. In this paper we use the statistical methods of pedigree analysis to address questions regarding a previously presumed hereditary form of blindness observed in a captive wolf population bred for conservation purposes in Scandinavian zoos. The most likely mode of inheritance coincides with an autosomal recessive allele with either a full penetrance or a reduced penetrance of 0.6 (depending on the reliability of studbook records). Using these two models of inheritance, we calculate the probability of carrying the blindness allele for each living animal. Analysis of the effect of removing high-probability carriers on founder allele survival and level of inbreeding demonstrates that the frequency of the deleterious allele can be significantly reduced without seriously affecting founder allele survival or current degree of inbreeding in the wolf population. 相似文献
34.
Linda Groat 《Journal of environmental psychology》1982,2(1):3-22
The relevance of the multiple sorting task as a research tactic for the empirical study of environmental meaning is illustrated in the context of a specific study of Modern and Post-Modern architecture. The assumption of architectural critics that Post-Modern buildings are more meaningful to the general public than Modern buildings forms the basis for the research hypotheses of this study. Twenty-four buildings, ranging from Modern to Post-Modern are evaluated by 20 architects and 20 accountants whose responses are structured through a multiple sorting task. The sorting data are interpreted in terms of regional analyses of multi-dimensional scaling structures, following the general principles of Facet Theory. These results suggest that (1) architects and accountants do employ different sets of criteria (different codes, in effect) for evaluating buildings, and yet (2) Post-Modern buildings (despite their architects' intentions of relating their designs to a popular code) are not perceived by the accountants as distinct from Modern buildings. The particular strengths of the multiple sorting task as a research tactic for this and other studies of environmental meaning are discussed and summarized. 相似文献
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Keeling LJ 《Ambio》2005,34(4-5):316-319
Good animal welfare is necessary if an agricultural system is to be sustainable. Although we have been concerned about the welfare of our animals since we first domesticated them and became dependent on their health and reproduction, this article focuses mainly on the development of the animal welfare debate since the 1960s. It presents animal welfare as a science that arose from society's concern about the way animals are kept. These moral and ethical concerns lead to it having a value framework that must also be taken into consideration. Different definitions of animal welfare, as well as examples of research, are presented and discussed in the light of developments in this area. For example, in recent years there has been an increased interest among consumers for animal-friendly products, as there has been for environment friendly products, and this has stimulated the move from experimental studies of animal welfare to its application in practice and to monitoring animal welfare on farms. Traditionally such measurements have been resource based, e.g. specifying the minimum amount of feeding space or the maximum stocking density, but now the trend is toward animal-based measures, such as the numberof lame animals, body condition, etc. 相似文献
36.
Studies of carbon fluxes in marine ecosystems are often done by using box model approaches with basin size boxes, or highly resolved 3D models, and an emphasis on the pelagic component of the ecosystem. Those approaches work well in the ocean proper, but can give rise to considerable problems when applied to coastal systems, because of the scale of certain ecological niches and the fact that benthic organisms are the dominant functional group of the ecosystem. In addition, 3D models require an extensive modeling effort. In this project, an intermediate approach based on a high resolution (20x20 m) GIS data-grid has been developed for the coastal ecosystem in the Laxemar area (Baltic Sea, Sweden) based on a number of different site investigations. The model has been developed in the context of a safety assessment project for a proposed nuclear waste repository, in which the fate of hypothetically released radionuclides from the planned repository is estimated. The assessment project requires not only a good understanding of the ecosystem dynamics at the site, but also quantification of stocks and flows of matter in the system. The data-grid was then used to set up a carbon budget describing the spatial distribution of biomass, primary production, net ecosystem production and thus where carbon sinks and sources are located in the area. From these results, it was clear that there was a large variation in ecosystem characteristics within the basins and, on a larger scale, that the inner areas are net producing and the outer areas net respiring, even in shallow phytobenthic communities. Benthic processes had a similar or larger influence on carbon fluxes as advective processes in inner areas, whereas the opposite appears to be true in the outer basins. As many radionuclides are expected to follow the pathways of organic matter in the environment, these findings enhance our abilities to realistically describe and predict their fate in the ecosystem. 相似文献
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Kimberley I. Shoaf Harvinder R. Sareen Loc H. Nguyen & Linda B. Bourque 《Disasters》1998,22(3):218-235
The devastating effects of earthquakes have been demonstrated repeatedly in the past decade, through moderate and major earthquakes such as the October 1987 Whittier Narrows earthquake (5.9 on the Richter scale), the October 1989 Loma Prieta earthquake (7.1) and the January 1994 Northridge earthquake (6.7). While 'official' tallies of injuries and deaths are reported for each event, the numbers vary from report to report. For Northridge, the number of injuries vary between 8,000 and 12,000; the number of deaths from 33 to 73 (Peek-Asa et al., 1997; Durkin, 1996).While official estimates are commonly reported following disasters, the study of actual numbers, types and causes of casualties has not developed. In this paper, we identify the numbers and risk factors for injuries within community-based samples across three earthquakes in urban California. We first report the numbers and types of injuries in each earthquake and then identify risk factors specifically associated with the Northridge earthquake 相似文献
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Many numerical models which describe the movement of a separate organic liquid phase in the subsurface require information about the relationships between capillary pressure and saturation, and between relative permeability and saturation. An evaluation of the information available for these relationships suggests that substantial discrepancies may be introduced into simulations if estimated, rather than measured, data are employed. The purpose of this study was to quantify these deviations. Two-phase displacement simulations were performed in one and two dimensions for several organic liquid-water systems. Both constant-head and constant-flux boundary conditions were employed at a variety of flow rates and time scales, using both measurements and estimates of capillary pressure and relative permeability for a sandy aquifer material. The results demonstrate that the use of estimated transport relationships produces significantly different predictions of organic liquid migration. The magnitude of the deviations between predictions may be as high as 25% or more after relatively short displacement periods, depending on the boundary conditions of the simulated scenario, as well as on the physical characteristics of the two-phase system. For the systems examined, most of the deviations resulted from the estimates for relative permeability to the organic liquid. Thus, improved methods for the estimation of the relative permeability to the organic liquid are needed to reduce the uncertainty in displacement simulations. 相似文献
40.
Four kinds of woods used for residential heating in Australia were selected and burned under two burning conditions in a domestic wood heater installed in a laboratory. The selected wood species included pine (Pinus radiata), red gum (Eucalvptus camaldulensis), sugar gum (Eucalyptus cladocalyx) and yellow box (Eucalyptus melliodora). The two different burning conditions represented fast burning and slow burning, with the air inlet of the combustion chamber respectively 'full open' and 'half open'. By sampling and analysing particulate and gaseous emissions from the burning of each load of wood under defined experimental conditions, PAHs emissions and their profiles in the particulate and gaseous phases were obtained. 16 species out of the 18 selected PAHs were detected. Of these, seven species were detected in the gaseous phase and most were lower molecular weight compounds.Similarly, more than 10 species of PAHs were detected in the particulate phase and these were mostly heavier molecular weight compounds. Under both burning conditions, emission levels for total PAHs and total genotoxic PAHs were the highest for pine and lowest for sugar gum, with red gum being the second highest, followed by yellow box. Using the specific sampling method, gaseous PAHs accounted for above 90% mass fraction of total PAHs in comparison to particulate PAHs (10%). The majority of the genotoxic PAHs were present in the particulate phase. PAHs emission levels in slow burning conditions were generally higher than those in fast burning conditions. 相似文献