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401.
Brázdil Rudolf Stucki Peter Szabó Péter Dobrovolný Petr Řezníčková Ladislava Kotyza Oldřich Valášek Hubert Dolák Lukáš Zahradníček Pavel Suchánková Silvie 《Theoretical and Applied Climatology》2018,132(3-4):1201-1216
Theoretical and Applied Climatology - One of the most disastrous windstorms to take place over the Czech Lands occurred on the night of 26/27 October 1870. It is here analysed through the use of... 相似文献
402.
Lucian?Sf?c?Email authorView authors OrcID profile Pavel?Ichim Liviu?Apostol Adrian?Ursu 《Theoretical and Applied Climatology》2018,134(3-4):777-791
The study underlines the characteristics of the urban heat island of Ia?i (Ia?i’s UHI) on the basis of 3 years of air temperature measurements obtained by fixed-point observations. We focus on the identification of UHI development and intensity as it is expressed by the temperature differences between the city centre and the rural surroundings. Annual, seasonal and daily characteristics of Ia?i’s UHI are investigated at the level of the classical weather observation. In brief, an intensity of 0.8 °C of UHI and a spatial extension which corresponds to the densely built area of the city were delineated. The Ia?i UHI is stronger during summer calm nights—when the inner city is warmer with 2.5–3 °C than the surroundings—and is weaker during windy spring days. The specific features of Ia?i’s UHI bear a profound connection to the specificity of the urban structure, the high atmospheric stability in the region and the local topography. Also, the effects of Ia?i’s UHI upon some environmental aspects are presented as study cases. For instance, under the direct influence of UHI, we have observed that in the city centre, the apricot tree blossoms earlier (with up to 4 days) and the depth of the snow cover is significantly lower (with up to 10 cm for a rural snow depth of 30 cm) than in the surrounding areas. 相似文献
403.
A spatiospectral localization method is discussed for processing the global geopotential coefficients from satellite mission
data to investigate time-variable gravity. The time-variable mass variation signal usually appears associated with a particular
geographical area yielding inherently regional structure, while the dependence of the satellite gravity errors on a geographical
region is not so evident. The proposed localization amplifies the signal-to-noise ratio of the (non-stationary) time-variable
signals in the geopotential coefficient estimates by localizing the global coefficients to the area where the signal is expected
to be largest. The results based on localization of the global satellite gravity coefficients such as Gravity Recovery And
Climate Experiment (GRACE) and Gravity and Ocean Circulation Explorer (GOCE) indicate that the coseismic deformation caused
by great earthquakes such as the 2004 Sumatra–Andaman earthquake can be detected by the low-low tracking and the gradiometer
data within the bandwidths of spherical degrees 15–30 and 25–100, respectively. However, the detection of terrestrial water
storage variation by GOCE gradiometer is equivocal even after localization. 相似文献
404.
The applicability of resistivity methods to ground water investigations is well recognized. As water-saturated rock formations
have a lower electrical resistivity than dry ones, an electrical resistivity survey should result in low resistivity anomalies. Normally, such anomalies are interpreted to indicate areas of potentially significant ground water flows. In karst areas,
however, interpretation may not be as straightforward: for example, large electrically conductive domains can represent water bearing zones, whose fluid-permeability may be poor; alternatively, fast flow conduits, which
may be unsaturated, occur as slender objects, and not as clear anomalous features. In order to deal with such extreme heterogeneities,
resistivity investigations require some specific adjustments. One example is the so-called “mise à la masse” method. In Romania,
it was used to trace the cold karst water inflows that detrimentally affected the commercial exploitation of a thermal spring,
Hercules at Baile Herculane. Conventional geoelectrical approaches––such as using resistivity highs to detect air-filled cave passages,
are proved to be less efficient in the considered karst investigations. 相似文献
405.
Chris Zevenbergen Sebastiaan van Herk Jeroen Rijke Pavel Kabat Pieter Bloemen Richard Ashley Andrew Speers Berry Gersonius William Veerbeek 《Natural Hazards》2013,65(3):1217-1225
There is a growing international recognition that flood risk management in optima forma should be a programmed and flexible process of continuously improving management practices by active learning about the outcome of earlier and ongoing interventions and drivers of change. In the Netherlands, such a long-term, adaptive flood risk management strategy is now being implemented. This so-called second Delta Programme aims to identify and exploit opportunities and capitalize on short-term benefits and opportunistic synergies that arise from change and will require adaptive policymaking. It also requires the financial and institutional means to operate in a long-lasting way, which at the very least, means engaging stakeholders, gathering and disseminating results and adaptation of future plans. Transferring the Dutch approach to other countries is a major challenge that calls for fundamental changes in institutional arrangements at various levels and thus requires customized programmes for strategic institutional change. Recent examples of transfer will provide important lessons of how institutional change can successfully occur and will contribute insights for other countries that attempting to reform their flood risk management strategies. Continuous monitoring and evaluation and sharing international experiences will become crucial for the effective delivery and wider uptake of these new strategies around the globe. 相似文献
406.
This study presents the first preliminary U–Pb zircon data on tin-bearing S-type granites from the Gemeric unit of the Western Carpathians (Slovakia). U–Pb single zircon dating controlled by cathodoluminescence suggests crystallization of the Gemeric granites during Permian to Early Triassic (303–241 Ma) time. Post-crystallization, low-temperature metamorphic overprint is reflected by partial Pb loss in zircons. These Gemeric granites are younger than the highly fractionated, S-type, tin- and rare-element-bearing leucogranites in the European Variscides. They may have resulted from partial melting, triggered by increased heat flow from the mantle below the continental crust, and most probably intruded during the post-collisional extension and initial rifting of the Variscan orogenic belt. During Alpine orogeny, the Gemeric granites were affected by a low-temperature deformation and metamorphism. 相似文献
407.
408.
409.
Pavel Kroupa † Jerome Bouvier 《Monthly notices of the Royal Astronomical Society》2003,346(2):369-380
410.
We present detailed data on 8 bright meteors recorded simultaneously by different observational techniques. All meteors were
recorded by all-sky cameras at the Czech stations of the European Fireball Network and by image intensified TV cameras placed
at Ondrejov and Kunzak observatories. As well as direct photographic and LLLTV recordings, most of meteors were recorded also
by the spectral TV camera and some also by photographic spectral cameras. For 6 cases, lightcurves from radiometers with very
high time resolution (1200 s−1) are also available. From all these detections we found a significant difference between TV and photographic beginning heights.
TV beginnings are in average about 40 km higher than the photographic ones. We found that meteor brightness is up to 2 magnitudes
higher in the photographic system than in the TV system. This difference for high velocity meteors is mainly caused by the
presence of strong Ca+ lines in the blue part of the spectrum, where the image intensifier is only marginally sensitive. At heights above 110 km,
the Na line is usually brighter than the Mg line, while at lower heights both lines have comparable brightness. In one of
two captured spectra of short duration luminous trains, a small initial brightening of the Mg and Na lines caused by recombination
processes was observed. 相似文献