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31.
Now is the time to refocus efforts in urban research and design. A changing climate and extreme weather events are presenting unique challenges to urban systems around the world. These challenges illuminate the social barriers that accompany disruptive events such as resource inequities and injustices. In this perspective, we provide three research priorities for just and sustainable urban systems that help to address these matters. The three research priorities are: (1) social equity and justice, (2) circularity, and (3) digital twins. Conceptual context and future research directions are provided for each. For social equity and justice, the future directions are mandatory equity analysis and inclusionary practices, understanding and reconciling historical injustices, and intentional integration with diverse community stakeholders. For circularity applications, they are better metrics for integration, more robust evaluation frameworks, and dynamic modeling at multiple spatial and temporal scales. Future directions for digital twins include developing principles to reduce complexity, integrating model and system components, and reducing barriers to data access. These research priorities are core to meeting several of the United Nations Sustainable Development Goals (i.e., 1—No Poverty, 8—Decent Work and Economic Growth, 10—Reduced Inequalities, and 11—Sustainable Cities and Communities). Useful social and technical matters are discussed throughout, where we highlight the importance of prioritizing localized research efforts, provide guidance for community-engaged research and co-development practices, and explain how these priorities interact to align with the evolving field of industrial ecology.  相似文献   
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Roads are a prominent feature of many landscapes, and high road densities create correspondingly high ecological impacts by altering landscape patterns, interrupting ecological flows, increasing erosion, fragmenting habitat, and facilitating the spread of invasive species. Here, we describe the construction of “near-natural greenways” that produce environmentally and socially harmonious road systems that meet the needs of both the environment and the socioeconomic development in China and that satisfy environmental, ecological, educational, traffic safety, economic, and sustainable developmental goals. In the last decade, China has embarked upon the implementation of a network of near-natural greenways with the vision of linking economic development with nature conservation by means of improved rehabilitation of existing road systems and improved construction of new roads. Ecological science, and especially landscape ecology, will play an important role in the planning and implementation of future near-natural greenways in China and around the world.  相似文献   
34.
An overview of various approaches for the realization of single‐material organic solar cells (SMOCs) is presented. Fullerene‐conjugated systems dyads, di‐block copolymers, and self‐organized donor‐acceptor molecules all represent different possible approaches towards SMOCs. Although each of them presents specific advantages and poses specific problems of design and synthesis, these different routes have witnessed significant progress in the past few years and SMOCs with efficiencies in the range of 1.50% have been realized. These performances are already higher than those of bi‐component bulk heterojunction solar cells some ten years ago, demonstrating that SMOCs can represent a credible approach towards efficient and simple organic solar cells. Possible directions for future research are discussed with the aim of stimulating further research on this exciting topic.  相似文献   
35.
Freshwater ostracodes show both an exceptionally high incidence of transitions to unisexuality and, in some cases, an extraordinary level of clonal diversity. There is no understanding of the agents promoting these transitions to thelytoky, although it has been suggested that their frequency may set the stage for sexual taxa to infuse clonal diversity into unisexuals. This study examines the nature and origins of clonal diversity in the unisexual ostracode Cyprinotus incongruens. A combination of allozyme and cytogenetic studies revealed the presence of two diploid clones of this species at three temperate sites and ten clones at one arctic site including three diploids, five triploids, and two tetraploids. The low heterozygosity (0%–20%) of its diploid clones suggests that parthenogenesis has arisen spontaneously in C. incongruens rather than through hybridization, as in vertebrate asexuals. Polyploid clones appear to owe their origin to genome additions from sexual taxa, although subsequent mutational divergence has played a role in further enhancing diversity. Two triploid clones have apparently originated from the incorporation of a haploid genome from the sexually reproducing C. glaucus, as evidenced by their high heterozygosity and possession of alleles otherwise found only in that species. Other polyploid clones have likely arisen as a result of interbreeding between bisexual and unisexual C. incongruens. These results suggest that both the incidence of spontaneous transitions to clonality and the frequency of interbreeding with relatives may be the key processes that govern clonal diversity in unisexual ostracodes.  相似文献   
36.
This analysis can be called energy accounting of solar water heating systems. Five types of solar water heating systems have been considered. With the help of material balance, energy content has been found in these systems. Yearly output of systems has been found by conducting transient simulations using hourly data of radiation and ambient temperature. Such analysis has been done separately for one representative city of each of six climatic zones of India. The energy payback for India ranges from 0.73 to 4.16 years for the thirty cases considered here.  相似文献   
37.
The genetic theory of infectious diseases has proposed that susceptibility to life-threatening infectious diseases in childhood, occurring in the course of primary infection, results mostly from individually rare but collectively diverse single-gene variants. Recent evidence of an ever-expanding spectrum of genes involved in susceptibility to infectious disease indicates that the paradigm has important implications for diagnosis and treatment. One such pathology is childhood herpes simplex encephalitis, which shows a pattern of rare but diverse disease-disposing genetic variants. The present report shows how proteomics can help to understand susceptibility to childhood herpes simplex encephalitis and other viral infections, suggests that proteomics may have a particularly important role to play, emphasizes that variation over the population is a critical issue for proteomics and notes some new challenges for proteomics and related bioinformatics tools in the context of rare but diverse genetic defects.  相似文献   
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Experimentation is at the heart of classical and modern behavioral ecology research. The manipulation of natural cues allows us to establish causation between aspects of the environment, both internal and external to organisms, and their effects on animals' behaviors. In recognition systems research, including the quest to understand the coevolution of sensory cues and decision rules underlying the rejection of foreign eggs by hosts of avian brood parasites, artificial stimuli have been used extensively, but not without controversy. In response to repeated criticism about the value of artificial stimuli, we describe four potential benefits of using them in egg recognition research, two each at the proximate and ultimate levels of analysis: (1) the standardization of stimuli for developmental studies and (2) the disassociation of correlated traits of egg phenotypes used for sensory discrimination, as well as (3) the estimation of the strength of selection on parasitic egg mimicry and (4) the establishment of the evolved limits of sensory and cognitive plasticity. We also highlight constraints of the artificial stimulus approach and provide a specific test of whether responses to artificial cues can accurately predict responses to natural cues. Artificial stimuli have a general value in ethological research beyond research in brood parasitism and may be especially critical in field studies involving the manipulation of a single parameter, where other, confounding variables are difficult or impossible to control experimentally or statistically.  相似文献   
40.
Ground beetle activity and species richness was monitored using pitfall traps in a plot trial system on a farm in northern England where the effects of organic and conventional fertility and crop protection management were separated within different crop types between 2005 and 2008. As well as analyses on species activity the beetles were split into small, medium‐sized and large groups, and into groups of herbivores and specific Collembola feeders. Crop type had significant effects on the activity of the 20 most abundant species and all groups, generally with most in beans and winter barley and least in vegetables and spring barley. Most significant reactions to crop protection and fertility management were in cereals and grass/clover. Activity of small species was highest in conventionally crop‐protected cereals but not in vegetables, with more medium‐sized and herbivorous species in organic plots, but there was little influence of crop protection management on large and Collembola feeding species. However, large species were significantly more active in organically fertilised cereals and grass/clover, but not in vegetables, and there were more Collembola feeders in conventional cereals but not in grass/clover. Small species were more abundant in conventionally fertilised grass/clover but there were more in organic cereals and vegetables. These inconsistent activity reactions to management were also observed with individual species but most preferred organically managed plots. There were few significant crop protection : fertility management interactions. Species richness was also significantly affected by crop type and where management had an influence, more species were found in organically managed plots. Constrained ordination emphasised that ground beetle activity was influenced more by crops than by management. Given the diverse nature of organic crop rotations, crop type should be considered a major influence in any environmental manipulation aimed at increasing ground beetle activity for provision of ecosystem services.  相似文献   
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