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661.
662.
Applied social area analysis: Defining and evaluating areas for urban neighbourhood councils 总被引:1,自引:0,他引:1
Derek R. Hall 《Geoforum》1977,8(5-6)
Urban neighbourhood councils, neither statutorily established nor widely initiated in England, are seen to possess a number of advantages over existing forms of representative participation in relation to the equitable distribution of resources. In Portsmouth a community area perception survey and principal components analysis of census data were undertaken to produce synthesised ‘best fit’ social sub-areas upon which to base neighbourhood councils. These areas were then analysed in terms of their relevance and appropriateness, terms specifically defined, along four scale dimensions. An original contention that for maximum effectiveness neighbourhood councils should be established to cover all urban residential areas was confounded by the manifest irrelevance of the neighbourhood council concept in certain socio-spatial contexts. 相似文献
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This study examined whether buried organic matter in the form of seagrass influenced colonization by the corophiid amphipod Paracorophium excavatum in an intertidal sandflat. Laboratory manipulations were compared to results from field studies to determine the role of hydrodynamics in mediating the effects of the organic matter. At levels of organic loading greater than 1% of sediment dry weight, size frequency effects and decreases in numbers of colonizers occurred in still water conditions. In the field, however, at levels of organics up to 2% of sediment dry weight, only size-frequency effects were observed. A change in hydrodynamic conditions and the influence of this on sediment geochemistry is suggested as the most reasonable explanation for the disparity in colonization both between sites in the field and between laboratory and field manipulations. Two effects of organics upon corophiid amphipod colonization are proposed: a lower level of organic loading that can lead to a greater proportion of juveniles in the colonizing population and a higher level of organics that can lead to a decrease in the numbers of amphipods colonizing. The threshold at which these effects take place is modulated by the hydrodynamics of the environment. The same organic addition can therefore have different effects upon colonization across a tidal flat, which is dependent upon the variation in hydrodynamics 相似文献
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Neal S. Gupta Hong Yang Qin Leng Derek E.G. Briggs George D. Cody Roger E. Summons 《Organic Geochemistry》2009,40(7):802-809
Analysis of modern Metasequoia leaves revealed the presence of the structural polyester cutin, guaiacyl lignin units and polysaccharides. Analysis of environmentally decayed Metasequoia leaves revealed that guaiacyl lignin units and cellulose were degraded more than vinyl phenol (the last being the primary pyrolysis product of cutin and plant cuticles) suggesting that cutin is more stable than lignin and cellulose during degradation, contrary to some previous studies. This observation is supported by electron microscopy showing changes in the cellular structure and cuticle of modern, decayed and fossil Metasequoia leaves. Metasequoia fossils from the Eocene of Republic (Washington State) showed a significant aliphatic component, but biopolymeric lignin and polysaccharides were not detected. Fossils from the Eocene of Axel Heiberg revealed the presence of lignin and an aliphatic polymer up to C29 with cellulose, and fossils from the Miocene Clarkia deposit (Idaho) revealed lignin and an aliphatic polymer up to C27 without any polysaccharides. Modern Metasequoia needles heated experimentally in confined conditions generated a macromolecular composition with an aliphatic polymer up to C32 and additional phenolic compounds similar to those present in the fossils. Experimental heating of cutin is known to generate an aliphatic polymer with carbon chain length units <C20. Thus, the n-alkyl component with chain length units >C20 in the heated Metasequoia needles is a product of incorporation of longer chain plant waxes, indicated by the odd/even predominance of the >C27 n-alkanes. The resistant nature of cutin compared to lignin and polysaccharides explains the presence of an n-alkyl component (<C20) in fossil leaves even when polysaccharides are absent and lignin has decayed; cutin and its diagenetically altered products contribute significantly to the presence of aliphatic components in terrestrially derived sedimentary organic matter. 相似文献
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Anjana Khatwa Ford 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(3-4):507-521
World Heritage Sites have a duty, through educational and information programmes, to strengthen appreciation and respect by their peoples of the cultural and natural heritage of that site. The Jurassic Coast World Heritage Site (JCWHS) showcases nearly 185 million years of Earth’s history across 95 miles of coast and exemplifies some of the most spectacular rocks, fossils and landforms in the world. However, imparting these values to non-specialist audiences of all ages, abilities and needs provides unique challenges and opportunities. A critical factor for success in addressing such a wide audience is ensuring that content is relevant, meaningful and focused on the expectations of the end user. In this paper we present our learning framework that is based around two approaches. Firstly, we map out the needs and expectations of each of our four core audience groups and set out guidelines for who we should aim our content at and how that should be delivered. Secondly, we set out three pathways (Inspire, Curious and Motivated) through which a person may choose to engage with the Jurassic Coast. We argue that if our tailored content and experiences can resonate with a person at an emotional and intellectual level, they will ultimately become devoted to the Jurassic Coast. Through empowering a community of people who understand and appreciate the geoheritage of the Jurassic Coast, they can become advocates and champions for its protection and conservation in the future. 相似文献
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Michele Ford 《Singapore journal of tropical geography》2008,29(2):130-132