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121.
Indigenous Australians’ knowledge of weather and climate 总被引:1,自引:1,他引:0
Although the last 200 years of colonisation has brought radical changes in economic and governance structures for thousands
of Aboriginal and Torres Strait Islanders living in remote areas of northern Australia, many of these Indigenous people still
rely upon, and live closely connected to, their natural environment. Over millennia, living ‘on country’, many of these communities
have developed a sophisticated appreciation of their local ecosystems and the climatic patterns associated with the changes
in them. Some of this knowledge is recorded in their oral history passed down through generations, documented in seasonal
weather calendars in local languages and, to a limited degree, transcribed and translated into English. This knowledge is
still highly valued by these communities today, as it is used to direct hunting, fishing and planting as well as to inform
many seasonally dependant cultural events. In recent years, local observations have been recognised by non-Indigenous scientists
as a vital source of environmental data where few historic records exist. Similar to the way that phenological observations
in the UK and US provide baseline information on past climates, this paper suggests that Indigenous observations of seasonal
change have the potential to fill gaps in climate data for tropical northern Australia, and could also serve to inform culturally
appropriate adaptation strategies. One method of recording recent direct and indirect climate and weather observations for
the Torres Strait Islands is documented in this paper to demonstrate the currency of local observations of climate and its
variability. The paper concludes that a comprehensive, participatory programme to record Aboriginal and Torres Strait Islander
knowledge of past climate patterns, and recent observations of change, would be timely and valuable for the communities themselves,
as well as contributing to a greater understanding of regional climate change that would be useful for the wider Australian
population. 相似文献
122.
Timothy Garn David A. Green Julia M. Riley Paul Alexander 《Monthly notices of the Royal Astronomical Society》2009,397(2):1101-1112
We probe the relationship between star formation rate (SFR) and radio synchrotron luminosity in galaxies at 0 < z < 2 within the northern Spitzer Wide-area Infrared Extragalactic survey (SWIRE) fields, in order to investigate some of the assumptions that go into calculating the star formation history of the Universe from deep radio observations. We present new 610-MHz Giant Metrewave Radio Telescope (GMRT) observations of the European Large-Area ISO Survey-North 2 (ELAIS-N2) field, and using this data, along with previous GMRT surveys carried out in the ELAIS-N1 (North 1) and Lockman Hole regions, we construct a sample of galaxies which have redshift and SFR information available from the SWIRE survey. We test whether the local relationship between SFR and radio luminosity is applicable to z = 2 galaxies, and look for evolution in this relationship with both redshift and SFR in order to examine whether the physical processes which lead to synchrotron radiation have remained the same since the peak of star formation in the Universe. We find that the local calibration between radio luminosity and star formation can be successfully applied to radio-selected high-redshift, high-SFR galaxies, although we identify a small number of sources where this may not be the case; these sources show evidence for inaccurate estimations of their SFR, but there may also be some contribution from physical effects such as the recent onset of starburst activity, or suppression of the radio luminosity within these galaxies. 相似文献
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124.
J.G. Blank S.J. Green D. Blake J.W. Valley N.T. Kita A. Treiman P.F. Dobson 《Planetary and Space Science》2009,57(5-6):533-540
Mars appears to have experienced little compositional differentiation of primitive lithosphere, and thus much of the surface of Mars is covered by mafic lavas. On Earth, mafic and ultramafic rocks present in ophiolites, oceanic crust and upper mantle that have been obducted onto land, are therefore good analogs for Mars. The characteristic mineralogy, aqueous geochemistry, and microbial communities of cold-water alkaline springs associated with these mafic and ultramafic rocks represent a particularly compelling analog for potential life-bearing systems. Serpentinization, the reaction of water with mafic minerals such as olivine and pyroxene, yields fluids with unusual chemistry (Mg–OH and Ca–OH waters with pH values up to ~12), as well as heat and hydrogen gas that can sustain subsurface, chemosynthetic ecosystems. The recent observation of seeps from pole-facing crater and canyon walls in the higher Martian latitudes supports the hypothesis that even present conditions might allow for a rock-hosted chemosynthetic biosphere in near-surface regions of the Martian crust. The generation of methane within a zone of active serpentinization, through either abiogenic or biogenic processes, could account for the presence of methane detected in the Martian atmosphere. For all of these reasons, studies of terrestrial alkaline springs associated with mafic and ultramafic rocks are particularly timely. This study focuses on the alkaline Adobe Springs, emanating from mafic and ultramafic rocks of the California Coast Range, where a community of novel bacteria is associated with the precipitation of Mg–Ca carbonate cements. The carbonates may serve as a biosignature that could be used in the search for evidence of life on Mars. 相似文献
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126.
Alison Olcott Marshall Frank A. Corsetti Alex L. Sessions Craig P. Marshall 《Organic Geochemistry》2009,40(11):1115-1123
Extractable biomarkers can help elucidate the environment and biota of ancient glaciations, although the method must be applied with care, as glacial sediments have a potential for incorporation of older detrital carbon. In Phanerozoic glacial sediments, the distinct elemental, molecular and isotopic compositions of the terrestrial and marine biomass allow discrimination between primary marine and redeposited terrestrial organic matter. However, as the Proterozoic biosphere was largely microbial and marine, biomarker and isotopic analyses are insufficient for distinguishing primary organic matter from secondary reworked organic matter. Here, we report the combined application of Raman spectroscopy and biomarker analysis to Precambrian glacial sediments, which, together, allows discrimination between mixed pools of organic carbon and provides a promising new approach for rapidly screening Precambrian sediments for immature organic matter amenable to biomarker analysis. 相似文献
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129.
Naomi Murdoch Patrick Michel Derek C. Richardson Kerstin Nordstrom Christian R. Berardi Simon F. Green Wolfgang Losert 《Icarus》2012,219(1):321-335
Surfaces of planets and small bodies of our Solar System are often covered by a layer of granular material that can range from a fine regolith to a gravel-like structure of varying depths. Therefore, the dynamics of granular materials are involved in many events occurring during planetary and small-body evolution thus contributing to their geological properties.We demonstrate that the new adaptation of the parallel N-body hard-sphere code pkdgrav has the capability to model accurately the key features of the collective motion of bidisperse granular materials in a dense regime as a result of shaking. As a stringent test of the numerical code we investigate the complex collective ordering and motion of granular material by direct comparison with laboratory experiments. We demonstrate that, as experimentally observed, the scale of the collective motion increases with increasing small-particle additive concentration.We then extend our investigations to assess how self-gravity and external gravity affect collective motion. In our reduced-gravity simulations both the gravitational conditions and the frequency of the vibrations roughly match the conditions on asteroids subjected to seismic shaking, though real regolith is likely to be much more heterogeneous and less ordered than in our idealised simulations. We also show that collective motion can occur in a granular material under a wide range of inter-particle gravity conditions and in the absence of an external gravitational field. These investigations demonstrate the great interest of being able to simulate conditions that are to relevant planetary science yet unreachable by Earth-based laboratory experiments. 相似文献
130.
Salles Lucas A. Vani Bruno C. Moraes Alison Costa Emanoel de Paula Eurico R. 《Surveys in Geophysics》2021,42(4):999-1025
Surveys in Geophysics - Over the last 15 years, the satellite constellation of the global positioning system (GPS) has been modernized for more precise applications, with the introduction... 相似文献