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551.
Mike Harrison 《Climatic change》2005,70(1-2):201-220
A review of the development and status of seasonal to inter-annual climate forecasting up until 2001 is presented covering not only the successes but also identifying some of the major challenges remaining. Included is discussion on the history of the enterprise; the scientific basis of modern seasonal to inter-annual prediction and its background of predictability theory; the current status of predictions and the measurement of their skill; the experiences and consequences of the 1997–1998 El Niño event; approaches to linking forecasts with applications; and a view to the future. 相似文献
552.
Mike Edmunds 《Astronomy& Geophysics》2005,46(4):4.12-4.17
Mike Edmunds follows the trail of the elements in his George Darwin Lecture, given to the RAS on 10 December 2004. 相似文献
553.
The short term climatic sensitivity of carbonate and silicate weathering fluxes: Insight from seasonal variations in river chemistry 总被引:2,自引:0,他引:2
Edward T. Tipper Mike J. Bickle A. Joshua West Hazel J. Chapman 《Geochimica et cosmochimica acta》2006,70(11):2737-2754
Large seasonal variations in the dissolved load of the headwater tributaries of the Marsyandi river (Nepal Himalaya) for major cations and 87Sr/86Sr ratios are interpreted to result from a greater dissolution of carbonate relative to silicate at high runoff. There is up to a 0.003 decrease in strontium isotope ratios and a factor of 3 reduction in the Si(OH)4/Ca ratio during the monsoon. These variations, in small rivers sampling uniform lithologies, result from a different response of carbonate and silicate mineral dissolution to climatic forcing. Similar trends are observed in compiled literature data, from both Indian and Nepalese Himalayan rivers. Carbonate weathering is more sensitive to monsoonal runoff because of its faster dissolution kinetics. Silicate weathering increases relative to carbonate during the dry season, and may be more predominant in groundwater with longer water-rock interaction times. Despite this kinetic effect, silicate weathering fluxes are dominated by the monsoon flux, when between 50% and 70% of total annual silicate weathering flux occurs. 相似文献
554.
Mike Hilton Nick Harvey Andrew Hart Kris James Chris Arbuckle 《The Australian geographer》2006,37(3):313-334
Marram grass (Ammophila arenaria) and sea-wheat grass (Thinopyrum junceiforme) have been introduced to Australia and New Zealand. This study examines the morphology of incipient foredunes and established foredunes associated with these species at two sites, Mason Bay in southern New Zealand, and the Younghusband Peninsula in South Australia. Both species invaded the existing foredunes very rapidly. In both cases the antecedent topography comprised relatively sparsely vegetated, irregular foredunes. Invasion resulted in continuous, regular, evenly vegetated foredunes. At Mason Bay a massive foredune has formed since 1958, in conjunction with Ammophila. Thinopyrum has formed an incipient foredune, with a ramp or terrace morphology, along the Younghusband Peninsula, South Australia. In both cases gaps in the former foredune have been closed and the indigenous foredune vegetation has been displaced. Both species may decrease the frequency and severity of blowout development. They are likely to be resilient to aeolian processes of sedimentation compared with dunes formed by indigenous species. Ammophila survives burial, is tolerant of drought and is resistant to erosion associated with storm surge and high waves. Thinopyrum is very tolerant of salinity. These species may adversely affect the long-term development of coastal barriers by inhibiting transgressive dune development. 相似文献
555.
556.
Mike Watson heralds the 2XMM catalogue, a valuable new X-ray astronomy resource compiled from XMM-Newton observations. 相似文献
557.
Ruth Bamford, Robert Bingham and Mike Hapgood discuss the physics behind shielding spacecraft from solar and cosmic radiation with mini-magnetospheres. 相似文献
558.
Mark C. PRICE Anton T. KEARSLEY Mark J. BURCHELL Lauren E. HOWARD Jon K. HILLIER Natalie A. STARKEY Penny J. WOZNIAKIEWICZ Mike J. COLE 《Meteoritics & planetary science》2012,47(4):684-695
Abstract– We present initial results from hydrocode modeling of impacts on Al‐1100 foils, undertaken to aid the interstellar preliminary examination (ISPE) phase for the NASA Stardust mission interstellar dust collector tray. We used Ansys’ AUTODYN to model impacts of micrometer‐scale, and smaller projectiles onto Stardust foil (100 μm thick Al‐1100) at velocities up to 300 km s?1. It is thought that impacts onto the interstellar dust collector foils may have been made by a combination of interstellar dust particles (ISP), interplanetary dust particles (IDP) on comet, and asteroid derived orbits, β micrometeoroids, nanometer dust in the solar wind, and spacecraft derived secondary ejecta. The characteristic velocity of the potential impactors thus ranges from <<1 to a few km s?1 (secondary ejecta), approximately 4–25 km s?1 for ISP and IDP, up to hundreds of km s?1 for the nanoscale dust reported by Meyer‐Vernet et al. (2009) . There are currently no extensive experimental calibrations for the higher velocity conditions, and the main focus of this work was therefore to use hydrocode models to investigate the morphometry of impact craters, as a means to determine an approximate impactor speed, and thus origin. The model was validated against existing experimental data for impact speeds up to approximately 30 km s?1 for particles ranging in density from 2.4 kg m?3 (glass) to 7.8 kg m?3 (iron). Interpolation equations are given to predict the crater depth and diameter for a solid impactor with any diameter between 100 nm and 4 μm and density between 2.4 and 7.8 kg m?3. 相似文献
559.
Bigg Grant R. Cropper T. E. O’Neill Clare K. Arnold Alex K. Fleming A. H. Marsh R. Ivchenko V. Fournier Nicolas Osborne Mike Stephens Robin 《Natural Hazards》2018,92(2):1113-1136
Natural Hazards - With the polar regions opening up to more marine activities but iceberg numbers more likely to increase than decline as a result of global warming, the risk from icebergs to... 相似文献
560.
Addi Bischoff Mike Komnik Jakob Storz Jasper Berndt 《Meteoritics & planetary science》2023,58(9):1260-1273
The lunar regolith breccia Dhofar 1769, which was found in 2012 as a single 125 g piece in the Zufar desert area of Oman, contains a relatively large, dark-colored impact melt breccia embedded in a fine-grained clastic matrix. The internal texture of the fragment indicates the repeated melt breccia formation on the lunar surface, their repeated brecciation, and mixing in second, third, and fourth generations of brecciated rock types. The chemical and mineralogical data reveal the incorporation of a feldspar-rich subophitic crystalline melt within a feldspar-rich microporphyritic crystalline melt breccia. This lithic paragenesis itself is embedded within a mafic, crystalline melt breccia. The entire breccia with the three different impact melts has been finally incorporated into the whole rock breccia. The three impact melts are mixtures of different source rocks and impact projectiles, based on the obtained minor and trace element compositions (in particular of Ni and the rare earth elements [REE]) of the impact melt lithologies. For all processes of impact melt formation, additional steps of their brecciation and re-lithification require a minimum number of seven impact processes. 相似文献