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171.
Bernard?HenryEmail author Kalin?Naydenov Dimo?Dimov Diana?Jordanova Neli?Jordanova 《International Journal of Earth Sciences》2012,101(3):747-759
The Kapitan-Dimitrievo pluton was emplaced within the 15 km wide Maritsa shear zone during the Late Cretaceous. It has well-known
U–Pb zircon age (78.54 ± 0.13 Ma) and appears as a late-syntectonic intrusion that marked the last ductile deformation in
the Maritsa shear zone. Magnetite is believed to be the main carrier of the magnetic fabric in this pluton, and crystallized
mainly late, after the main rock-forming minerals. Two fabrics are recorded, a visible syn-magmatic fabric (due to magma flow)
and magnetic late-magmatic fabric (related to regional stresses). Although different, both are mainly related to the shearing
along this shear zone. These results constrain in age the dextral strike-slip controlled emplacement and evolution of the
Late Cretaceous plutons from Central Bulgaria. 相似文献
172.
Bernard Marandat Sylvain Adnet Laurent Marivaux Alain Martinez Monique Vianey-Liaud Rodolphe Tabuce 《Swiss Journal of Geoscience》2012,105(3):417-434
A new mammal fauna from the earliest Eocene of Le Clot (Corbières, Southern France) is described. Some taxa identified there, such as Corbarimys hottingeri and Paschatherium plaziati, allow a correlation with the previously described Corbières fauna of Fordones. Moreover, the presence at Le Clot of Lessnessina praecipuus, which is defined in Palette (Provence, Southern France) allows correlating both localities. All three of these localities are referred to the MP7 reference level, even if a direct correlation with the type locality of MP7 (Dormaal, Belgium) is not ascertained. A Southern Europe biochronological sequence is proposed for the beginning of the Eocene: Silveirinha, Fordones/Palette/Le Clot, Rians/Fournes. The diagnosis of a new species of a neoplagiaulacid multituberculate (?Ectypodus riansensis nov. sp.) is proposed. From a compilation of data concerning the earliest Eocene faunas from both Northern Europe and Southern Europe, we conclude that two faunas corresponding to two distinct palaeobiogeographical provinces existed in Western Europe. This faunal disparity, probably related to climatic differences, makes correlations particularly difficult between the two provinces. 相似文献
173.
Harm Bartholomeus Lammert Kooistra Antoine Stevens Martin van Leeuwen Bas van Wesemael Eyal Ben-Dor Bernard Tychon 《International Journal of Applied Earth Observation and Geoinformation》2011
Soil Organic Carbon (SOC) is one of the key soil properties, but the large spatial variation makes continuous mapping a complex task. Imaging spectroscopy has proven to be an useful technique for mapping of soil properties, but the applicability decreases rapidly when fields are partially covered with vegetation. In this paper we show that with only a few percent fractional maize cover the accuracy of a Partial Least Square Regression (PLSR) based SOC prediction model drops dramatically. However, this problem can be solved with the use of spectral unmixing techniques. First, the fractional maize cover is determined with linear spectral unmixing, taking the illumination and observation angles into account. In a next step the influence of maize is filtered out from the spectral signal by a new procedure termed Residual Spectral Unmixing (RSU). The residual soil spectra resulting from this procedure are used for mapping of SOC using PLSR, which could be done with accuracies comparable to studies performed on bare soil surfaces (Root Mean Standard Error of Calibration = 1.34 g/kg and Root Mean Standard Error of Prediction = 1.65 g/kg). With the presented RSU approach it is possible to filter out the influence of maize from the mixed spectra, and the residual soil spectra contain enough information for mapping of the SOC distribution within agricultural fields. This can improve the applicability of airborne imaging spectroscopy for soil studies in temperate climates, since the use of the RSU approach can extend the flight-window which is often constrained by the presence of vegetation. 相似文献
174.
An online survey about climate change was conducted 2008/2009 among all university members (N = 3541). Using the Theory of
Planned Behavior and Cultural Theory within a structural equation modeling approach, one main goal was to explain climate-friendly
behavioral intentions and the underlying psychological processes comprehensively and to show the interdependencies between
both approaches. The model explained 72% of the variance in Intentions to use public transport. Attitude towards public transport
(beta = 0.67, p < .001) most strongly influenced Intentions followed by Subjective Norms (beta = 0.23, p < .001). In turn,
Attitudes and Norm were explained by the value types Egalitarian, Individualist and Fatalist (24% and 14% respectively). These
value types are mediated through Attitudes and Subjective Norms. Recommendations regarding the support of climate friendly
behavior are formulated. 相似文献
175.
Influence of coupling on atmosphere, sea ice and ocean regional models in the Ross Sea sector, Antarctica 总被引:1,自引:0,他引:1
Nicolas C. Jourdain Pierre Mathiot Hubert Gallée Bernard Barnier 《Climate Dynamics》2011,36(7-8):1523-1543
Air–sea ice–ocean interactions in the Ross Sea sector form dense waters that feed the global thermohaline circulation. In this paper, we develop the new limited-area ocean–sea ice–atmosphere coupled model TANGO to simulate the Ross Sea sector. TANGO is built up by coupling the atmospheric limited-area model MAR to a regional configuration of the ocean–sea ice model NEMO. A method is then developed to identify the mechanisms by which local coupling affects the simulations. TANGO is shown to simulate realistic sea ice properties and atmospheric surface temperatures. These skills are mostly related to the skills of the stand alone atmospheric and oceanic models used to build TANGO. Nonetheless, air temperatures over ocean and winter sea ice thickness are found to be slightly improved in coupled simulations as compared to standard stand alone ones. Local atmosphere ocean feedbacks over the open ocean are found to significantly influence ocean temperature and salinity. In a stand alone ocean configuration, the dry and cold air produces an ocean cooling through sensible and latent heat loss. In a coupled configuration, the atmosphere is in turn moistened and warmed by the ocean; sensible and latent heat loss is therefore reduced as compared to the stand alone simulations. The atmosphere is found to be less sensitive to local feedbacks than the ocean. Effects of local feedbacks are increased in the coastal area because of the presence of sea ice. It is suggested that slow heat conduction within sea ice could amplify the feedbacks. These local feedbacks result in less sea ice production in polynyas in coupled mode, with a subsequent reduction in deep water formation. 相似文献
176.
Based on the data of the detailed earthquake catalog provided on the website of the Corinth Rift Laboratory, zones of swarm
activity are revealed and the variations in the statistical parameters of seismic swarms that occurred in the western part
of the Gulf of Corinth are calculated. The preliminary analysis of the catalogue is carried out; the magnitude of completeness
and the accuracy of the location of the earth-quake are estimated; the changes in these parameters associated with the development
of the observational network are assessed. The b-value (b-values) and the cluster dimension of the set of hypocenters are estimated, and time variations in these parameters in the
course of the evolution of swarm activity are revealed. The style of changes in the parameters characterizing the seismic
regime during intervals of swarm activity indicates that the process of failure exhibits scale redistribution over the course
of time, changing from upscaling (progression from smaller to larger scales) at the stage of increasing seismicity to downscaling
(progression from larger to lower scales) at the stage of decay. These particular features of enhancement and reduction of
swarm seismicity are qualitatively similar to the scenarios of source preparation and aftershock relaxation of strong earthquakes.
The pattern of variations of the swarm seismicity studied is similar to those identified in the previous laboratory and field
modeling of various transient modes of seismicity. This fact confirms the relevancy of the retrieved results and conclusions
based on the laboratory studies of transient modes, and suggests that the latter have a universal governing mechanism. 相似文献
177.
178.
179.
Michio J. Kishi Shin-ichi Ito Bernard A. Megrey Kenneth A. Rose Francisco E. Werner 《Journal of Oceanography》2011,67(1):3-16
The evolution of the North Pacific Ecosystem Model for Understanding Regional Oceanography (NEMURO) family of models to study
marine ecosystems is reviewed. Applications throughout the North Pacific have shown the models to be robust and to be able
to reproduce 1D, 2D and 3D components of nutrient, carbon cycle and biogeochemical cycles as well as aspects of the lower
trophic levels ecosystem (phyto- and zooplankton). NEMURO For Including Saury and Herring, an extension that includes higher
trophic levels, can be run uncoupled or coupled to NEMURO. In the uncoupled mode, the growth and weight of an individual fish
is computed using plankton densities simulated by NEMURO but with no feedback between fish consumption and plankton mortality.
In the coupled mode, the feeding, growth and weight of a representative fish are computed, and prey removals due to feeding
by fish appear as mortality terms on the prey. The NEMURO family of models continues to evolve, including effects of the microbial
loop and iron limitation at lower trophic levels, and full life cycle, multi-species and multi-generational simulations at
higher trophic levels. We outline perspectives for future end-to-end modeling efforts that can be used to study marine ecosystems
in response to global environmental change. 相似文献
180.
Denis Lacelle Bernard Lauriol Grant Zazula Bassam Ghaleb Nicholas Utting Ian D. Clark 《Quaternary Research》2013
This study presents new ages for the northwest section of the Laurentide Ice Sheet (LIS) glacial chronology from material recovered from two retrogressive thaw slumps exposed in the Richardson Mountains, Northwest Territories, Canada. One study site, located at the maximum glacial limit of the LIS in the Richardson Mountains, had calcite concretions recovered from aufeis buried by glacial till that were dated by U/Th disequilibrium to 18,500 cal yr BP. The second site, located on the Peel Plateau to the east yielded a fossil horse (Equus) mandible that was radiocarbon dated to ca. 19,700 cal yr BP. These ages indicate that the Peel Plateau on the eastern flanks of the Richardson Mountains was glaciated only after 18,500 cal yr BP, which is later than previous models for the global last glacial maximum (LGM). As the LIS retreated the Peel Plateau around 15,000 cal yr BP, following the age of the Tutsieta phase, we conclude that the presence of the northwestern margin of the LIS at its maximum limit was a very short event in the western Canadian Arctic. 相似文献