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991.
We present a case of prenatal diagnosis of Werdnig-Hoffmann disease, the most severe type of spinal muscular atrophy (SMA). DNA obtained from a mummified umbilical cord of a deceased affected brother of the index case was analysed with four closely linked microsatellite markers [EF1/2a and EF13/14 (D5S125), MAP1B, and JK53CA (D5S112)], flanking the SMA gene, on chromosome 5q11·2-13·3. The fetus was diagnosed as homozygous for the deleterious SMA gene.  相似文献   
992.
Fernando de Noronha is a small volcanic archipelago in the Southern Atlantic, some 350 km NE of the city of Natal in NE Brazil. These remote volcanic islands represent a largely pristine environment, distant from sources of anthropogenic contamination. This study was carried out to determine the natural concentrations of Ag, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, V and Zn in the A and B horizons of soils of Fernando de Noronha. The aims of the study were twofold: determine whether there is a relationship between the bedrock geology and soils and to establish quality reference values for soils from Fernando de Noronha. Soil samples were subjected to acid digestion by the USEPA method 3051A, and metals were determined by inductively coupled plasma emission spectrophotometry. The results showed that the trace element distribution largely reflects the geochemistry of the underlying volcanic rocks of the Remedios and Quixaba Formations. The results demonstrate that the concentrations of Ba, Cr, Zn, Ni and Cu from the soils of the volcanic Fernando de Noronha archipelago are higher than those found in soils from continental Brazil. However, concentrations of Ni, Cu and Co are lower in soils of the archipelago as compared to other volcanic islands throughout the world. The elevated trace element concentrations of the volcanic parent material of Fernando de Noronha soils seem to be the main factor governing the relatively high natural concentrations of trace elements.  相似文献   
993.
Nature-based solutions (NBS), understood as actions that use ecosystem processes to address societal needs, can play important roles to future-proof river landscape development for people and nature. However, knowledge gaps exist how NBS can be planned and implemented at landscape scales. This Special Issue brings together insights and experiences from studies of assessing, planning, and implementing NBS in river landscapes in Europe and beyond. It addresses three research fields: (i) NBS effects, looking at the effectiveness of NBS to achieve ecological, social, and/or economic outcomes, (ii) NBS planning, focusing on approaches for planning and designing NBS, and (iii) NBS governance, relating to governance and business models for implementation. The twelve contributions deliver evidence on how NBS outperform conventional, rather technical solutions, provide guidance and tools to operationalize the NBS concept into practice, and showcase successful governance models of NBS in different contexts. The editorial ends with an outlook on further research needs.  相似文献   
994.
The presence of natural organic matter (NOM) strongly impacts drinking water treatment, water quality, and water behavior during distribution. Dissolved organic carbon (DOC) concentrations were determined daily over a 22 month period in river water before and after conventional drinking water treatment using an on-line total organic carbon (TOC) analyzer. Quantitative and qualitative variations in organic matter were related to precipitation and runoff, seasons and operating conditions. Following a rainfall event, DOC levels could increase by 3.5 fold over baseflow concentrations, while color, UV absorbance values and turbidity increased by a factor of 8, 12 and 300, respectively. Treated water DOC levels were closely related to the source water quality, with an average organic matter removal of 42% after treatment.  相似文献   
995.
In river basins transformation from traditions of reactive flood defense to more adaptive management regimes is difficult. How regime components reinforce each other to set its development path may induce inertia and path dependency. Transformation may require profound shifts in the institutions, technologies, and personnel as well as the ecological, economic and social processes they influence in setting the basin's trajectory. Regime change has become an issue in Hungary following repeated failures of conventional management policies to handle a series of floods on the Tisza river starting in 1997. Increasing public participation pushed water policy debate toward more experimentation with alternatives, but implementation appears stalled. In this paper we review hypotheses about what factors are bridges or barriers to transformation and then use the Management Transition Framework to examine how the interactions linking action situations, operational outcomes, knowledge and institutions influenced the river management policy debate in Hungary from 1997 to 2009. Specifically we examined which factors characteristic of conventional Control vs. progressive Adaptive management regimes influenced these interactions in ways that contributed to or hindered transformation. We found that governance and social learning issues predominated, with lesser roles played by factors related to integration of sectors and different levels in the science and policy of river management.  相似文献   
996.
The goal oriented framework (GOF) for indicators has been developed as part of a comprehensive research project developing computerised tools for integrated assessment of the effects of new policies or technologies on agricultural systems (SEAMLESS-IF). The ambition has therefore been to create an indicator framework where the environmental, economic and social dimensions of sustainable development can be related to each other in a consistent way. Integrated assessment tools rely on such frameworks to capture and visualise trade-offs (antagonisms or synergies) among indicators between and within the three dimensions of sustainable development. The specific aims of this paper are to (i) present the GOF (ii) present how the GOF can be used to select indicators within the integrated assessment framework SEAMLESS-IF and (iii) discuss the advantages and limitations with the proposed approach. We show that the GOF has several advantages. Its major rewards are its relative simplicity and the possibility to link indicators to policy goals of each dimension of sustainability and thereby facilitate the comparison of the impacts of the new policy on the different dimensions. Another important feature of the GOF is its multi-scale perspective, which will enable the comparison of effects of a new policy between scales. Yet, as typical for all indicator frameworks, the GOF has also biases either instigated by the issues the included models cover or by the stakeholders’ selection of indicators. However, due to the way the GOF and its indicators are technically implemented in SEAMLESS-IF, it can easily be extended and include new indicators to increase and update its policy relevance.  相似文献   
997.
A better understanding of corporate strategy under regulatory uncertainty enables policy makers to improve policy making efficiency and enhance regulations’ effectiveness. Based on a review of the literature on policy formulation, we propose that regulatory uncertainty is characterized by a dependence on political negotiation, a discrete scenario structure, and a discontinuous resolution. Data from a worldwide survey show that firms pursue response strategies to regulatory uncertainty that address these characteristics by participating in policy making and increasing strategic flexibility. Surprisingly, the results also show that regulatory uncertainty only partly causes firms to postpone strategic decisions. We find that existing regulation and a need to act quickly despite regulatory uncertainty are opposed to the pursuit of a postponement strategy. We conclude that improving the mechanisms by which firms participate in early stages of the policy making process could enable them to operate in a more target-oriented manner, allow for more efficient policy implementation, and increase a regulation's effectiveness.  相似文献   
998.
The short-sighted selection hypothesis for parasite virulence predicts that winners of within-host competition are poorer at transmission to new hosts. Social parasitism by self-replicating, female-producing workers occurs in the Cape honeybee Apis mellifera capensis, and colonies of other honeybee subspecies are susceptible hosts. We found high within-host virulence but low transmission rates in a clone of social parasitic A. m. capensis workers invading the neighbouring subspecies A. m. scutellata. In contrast, parasitic workers from the endemic range of A. m. capensis showed low within-host virulence but high transmission rates. This suggests a short-sighted selection scenario for the host-parasite co-evolution in the invasive range of the Cape honeybee, probably facilitated by beekeeping-assisted parasite transmission in apiaries.  相似文献   
999.
How is behaviour organised across sensory modalities? Specifically, we ask concerning the fruit fly Drosophila melanogaster how visual context affects olfactory learning and recall and whether information about visual context is getting integrated into olfactory memory. We find that changing visual context between training and test does not deteriorate olfactory memory scores, suggesting that these olfactory memories can drive behaviour despite a mismatch of visual context between training and test. Rather, both the establishment and the recall of olfactory memory are generally facilitated by light. In a follow-up experiment, we find no evidence for learning about combinations of odours and visual context as predictors for reinforcement even after explicit training in a so-called biconditional discrimination task. Thus, a ‘true’ interaction between visual and olfactory modalities is not evident; instead, light seems to influence olfactory learning and recall unspecifically, for example by altering motor activity, alertness or olfactory acuity.  相似文献   
1000.
Environmental Science and Pollution Research - The evaluation of soil quality requires the use of robust methods to assess biologically based indicators. Among them, enzyme activities are used for...  相似文献   
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