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991.
Miriam Baglioni Emiliano Giovannetti Maria Vittoria Masserotti Chiara Renso Laura Spinsanti 《Transactions in GIS》2008,12(Z1):31-44
Querying geographical information systems has been recognized as a difficult task for non‐expert users. Furthermore, user queries are often characterized by semantic aspects not directly managed by traditional spatial databases or GIS. Examples of such semantic geospatial queries are the use of implicit spatial relations between objects, or the reference of domain concepts not explicitly represented in data. To handle such queries, we envisage a system that translates natural language queries into spatial SQL statements on a database, thus improving standard GIS with new semantic capabilities. Within this general objective, the contribution of this article is to introduce a methodology to handle semantic geospatial queries issued over a spatial database. This approach captures semantics from an ontology built upon the spatial database and enriched by domain concepts and properties specifically defined to represent the localization of objects. Some examples of the use of the methodology in the urban domain are presented. 相似文献
992.
Covadonga Brime Maria Cristina Perri Monica Pondrelli Claudia Spalletta Corrado Venturini 《International Journal of Earth Sciences》2008,97(6):1213-1229
Thermal evolution of the Palaeozoic–Triassic sequences of the Carnic Alps has been characterized by b cell dimension and Kübler Index (illite “crystallinity”) of K-white micas (KI), árkai Index (AI) of chlorites, clay mineral
assemblages and conodont Colour Alteration Index (CAI). Data indicate at least two metamorphic events, Variscan and Alpine.
In the older event high anchizonal conditions predominated although epizonal conditions were reached over wide areas. It was
characterized by low-intermediate pressure facies. The thermal peak was mainly due to an extensional regime during the Bashkirian.
A younger thermal overprint generated by Alpine orogeny was of lower grade, reaching high diagenetic–anchizonal conditions
characterized by high-pressure facies. Inverted metamorphic patterns are associated with middle to late Miocene thrusting.
Hydrothermal alteration in the northern part of the region can be linked with emplacement of Oligocene plutons and high heat
flow along the Periadratic lineament.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
993.
Aschonitis Vassilis Diamantopoulou Maria Papamichail Dimitris 《Theoretical and Applied Climatology》2018,132(3-4):1165-1186
Theoretical and Applied Climatology - The aim of the study is to propose new modeling approaches for daily estimations of crop coefficient K c for flooded rice (Oryza sativa L., ssp. indica) under... 相似文献
994.
Michael Traut Alice Larkin Kevin Anderson Christophe McGlade Maria Sharmina Tristan Smith 《Climate Policy》2018,18(8):1066-1075
The Paris Agreement, which entered into force in 2016, sets the ambitious climate change mitigation goal of limiting the global temperature increase to below 2°C and ideally 1.5°C. This puts a severe constraint on the remaining global GHG emissions budget. While international shipping is also a contributor to anthropogenic GHG emissions, and CO2 in particular, it is not included in the Paris Agreement. This article discusses how a share of a global CO2 budget over the twenty-first century could be apportioned to international shipping, and, using a range of future trade scenarios, explores the requisite cuts to the CO2 intensity of shipping. The results demonstrate that, under a wide range of assumptions, existing short-term levers of efficiency must be urgently exploited to achieve mitigation commensurate with that required from the rest of the economy, with virtually full decarbonization of international shipping required as early as before mid-century.
Key policy insights
Regulatory action is key to ensuring the international shipping sector’s long-term sustainability.
For the shipping industry to deliver mitigation in line with the Paris Agreement, virtually full decarbonization needs to be achieved.
In the near term, immediate and rapid exploitation of available mitigation measures is of critical importance.
Any delay in the transition will increase the risk of stranded assets, or diminish the chances of meeting the Paris Agreement's temperature commitments.
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The role of floating mucilage in the invasive spread of the benthic microalga Chrysophaeum taylorii 下载免费PDF全文
Sarah Caronni Maria Anna Delaria Kirsten Heimann Giovanni Macri Augusto Navone Pieraugusto Panzalis Giulia Ceccherelli 《Marine Ecology》2016,37(4):867-876
Chrysophaeum taylorii Lewis & Bryan (Pelagophyceae) is a mucilage‐producing benthic microalga that has recently begun to spread in the Mediterranean Sea, where a range expansion is occurring. This paper presents the results of three field experiments that aimed to increase the knowledge on mucilage provision mechanisms for this benthic microalga and to evaluate the importance of mucilage in its range expansion. By means of two correlative field experiments (several years of data were considered to encompass the variability of mucilage cover) we found that, on the sea bottom, mucilage cover does not depend on epilithic cell density and that both its cover and settling are affected by water flow. We also tested the hypothesis that cells embedded in floating mucilage fall on the underlying substratum, where their abundance depends on water flow. To this aim, in the field we manipulated the presence of floating mucilaginous aggregates in cages with different levels of exposure to winds. The abundance of C. taylorii cells on the substratum under cages with mucilage was compared with that of two control treatments: cages without mucilage and mucilage in still water, in the field and lab, respectively. The results suggested that mucilage can represent an excellent strategy for the species to disperse, as C. taylorii cells fall from the floating mucilage and, if the water flow is unimportant, settle on hard substrata just underneath the cage. This study enriches the portfolio of knowledge of the dispersal strategies of microalgae and contributes to the understanding of the spread of invasive species. 相似文献
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Iván Morales-Arredondo Ramiro Rodríguez Maria Aurora Armienta Ruth Esther Villanueva-Estrada 《Hydrogeology Journal》2016,24(4):1029-1044
A groundwater sampling campaign was carried out in the summer of 2013 in a low-temperature geothermal system located in Juventino Rosas (JR) municipality, Guanajuato State, Mexico. This groundwater presents high concentrations of As and F? and high Rn counts, mainly in wells with relatively higher temperature. The chemistry of major elements was interpreted with different methods, like Piper and D’Amore diagrams. These diagrams allowed for classification of four groundwater types located in three hydrogeological environments. The aquifers are hosted mainly in alluvial-lacustrine sediments and volcanic rocks in interaction with fault and fracture systems. The subsidence, faults and fractures observed in the study area can act as preferential channels for recharge and also for the transport of deep fluids to the surface, especially in the basin plain. The formation of a piezometric dome and the observed hydrochemical behavior of groundwater suggest a possible origin of the As and F?. Geochemical processes occurring during water–rock interaction are related to high concentrations of As and F?. High temperatures and alteration processes (like rock weathering) induce dissolution of As and F?-bearing minerals, increasing the content of these elements in groundwater. 相似文献
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