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791.
A. G. Zatsepin A. G. Ostrovskii V. V. Kremenetskiy S. S. Nizov V. B. Piotukh V. A. Soloviev D. A. Shvoev A. L. Tsibul’sky S. B. Kuklev O. N. Kukleva L. V. Moskalenko O. I. Podymov V. I. Baranov A. A. Kondrashov A. O. Korzh A. A. Kubryakov D. M. Soloviev S. V. Stanichny 《Izvestiya Atmospheric and Oceanic Physics》2014,50(1):13-25
The first data on the creation of the subsatellite polygon on the Black Sea shelf and continental slope in the Gelendzhik area (designed in order to permanently monitor the state of the aquatic environment and biota) and the plans for maintaining and developing this polygon are presented. The autonomous measuring systems of the polygon in the composition of bottom stations with acoustic Doppler current profilers (ADCP), Aqualog robotic profilers, and thermo-chains on moored buoy stations should make it possible to regularly obtain hydrophysical, hydrochemical, and bio-optical data with a high spatial-time resolution and transmit these data to the coastal center on a real-time basis. These field data should be used to study the characteristics and formation mechanisms of the marine environment and biota variability, as well as the water-exchange processes in the shelf-deep basin system, ocean-atmosphere coupling, and many other processes. These data are used to calibrate the satellite measurements and verify the water circulation numerical simulation. It is assumed to use these data in order to warn about the hazardous natural phenomena and control the marine environment state and its variation under the action of anthropogenic and natural factors, including climatic trends. It is planned to use the polygon subsatellite monitoring methods and equipment in other coastal areas, including other Black Sea sectors, in order to create a unified system for monitoring the Black Sea shelf-slope zone. 相似文献
792.
Tishchenko P. Ya. Khodorenko N. D. Barabanshchikov Yu. A. Volkova T. I. Mar’yash A. A. Mikhailik T. A. Pavlova G. Yu. Sagalaev S. G. Semkin P. Yu. Tishchenko P. P. Shvetsova M. G. Shkirnikova E. M. 《Oceanology》2020,60(3):341-352
Oceanology - In February and July 2014, multidisciplinary geochemical studies of the sediments were carried out at two stations. One of them was located in Voevoda Bight, which has a bottom depth... 相似文献
793.
Analysis of carbonate microfossils (planktonic foraminifers and nannoplankton) in the DSDP Hole 362 Quaternary section made
it possible to specify its zonal subdivision (almost all zones of Gartner’s high-resolution nannofossil scale are recognized),
establish depositional environments, and restore past surface water temperatures. The latter appeared to be several degrees
lower than their present-day values, which is evident from the anomalously high share of the subpolar species Neogloboquadrina pachyderma sin. that constitutes 97% of the fossil assemblage in Lower Pleistocene sediments. It is shown that the Benguela upwelling
existed throughout the entire Pleistocene, being less intense in the Late Pleistocene and Holocene. 相似文献
794.
E. L. Shkol’nik G. N. Baturin E. A. Zhegallo B. L. Zalishchak I. A. Basov 《Oceanology》2006,46(1):95-104
Phosphatized biogenic limestones and phosphorites with initial Fe-Mn mineralization dredged from the summit surface of the Kammu Seamount (Milwaukee Seamounts, northwestern Pacific) are studied. The rocks are largely composed of nannofossils and planktonic foraminifers with an admixture of benthic foraminifers, bryozoans, and other organic remains, presumably including bacterial ones. The nannofosssil and foraminiferal assemblages indicate the Quaternary age of the sediments, and their phosphatization is consistent with the phosphatization age determined previously based on nonequilibrium uranium (within the limits of 1 My). The age of phosphatization and the Fe-Mn mineralization in the sediments from Pacific seamounts that young implies the dependence of these ore-forming processes on oceanic environments favorable for ore accumulation rather than on their age. 相似文献
795.
A. N. Fakhrutdinova V. V. Gur’yanov A. Yu. El’kin 《Izvestiya Atmospheric and Oceanic Physics》2006,42(1):60-67
The distributions of kinetic energy (KE) and available potential energy (APE) in the lower and middle atmosphere of the Northern and Southern hemispheres over the period 1992–2003 are investigated. Annual mean values of the amplitude and phase of annual and semiannual oscillations in the zonal and eddy forms of KE and APE are calculated in the height range 0–55 km (1000–0.316 hPa) for the 21st layer. A clearly pronounced annual cycle of the zonal and eddy components of KE and APE with maxima in the winter season are observed in the troposphere of both hemispheres. In the lower stratosphere, the annual-cycle maximum is shifted toward the summer season because of the meridional gradient of the zonal mean temperature. In the stratosphere of both hemispheres, along with annual oscillations, semiannual oscillations are present in all forms of energy. The intensity of these oscillations for the zonal KE and APE at the upper-stratosphere heights is comparable to the intensity of annual oscillations. A local structure of the energy regime of the upper mesosphere-lower thermosphere is investigated against the background of the global energy regime from the data of meteor sounding in Kazan. It is shown that, for both the global and regional regimes, specific features of the phase profiles of energy characteristics can be explained by the presence of barriers during the propagation of wave disturbances along the vertical. 相似文献
796.
Statistical relations of the run-up height of Tsunami waves to the distance and energy of the source
A statistical analysis of the relation between the run-up height of historical tsunami events and the distance and magnitude of the source was performed on the basis of the known Historical Tsunami Data Base [5]. The sample from the database used for the analysis comprises 5638 run-ups caused by 628 seismic events. This analysis, together with the dimensionality theory, shows that the statistical average of the run-up height is inversely proportional to the distance from the source to a power close to 1/2 (that is characteristic of the cylindrically symmetrical case) and directly proportional to the 3/8 power of the earthquake energy. 相似文献
797.
The compositions, structures, and microstructures of different types of phosphorites and poorly phosphatized rocks from low atolls in the near-equatorial part of the Western Indian Ocean are described. The rocks were examined under optical and scanning microscopes using microprobing techniques and etching of selected samples with weak solvents as well as with the help of chemical analyses. It is proved that phosphorites have been formed owing to the uneven phosphatization of the primary carbonate rocks; the degree of their phosphatization ranges from traces to 40% P2O5. In the phosphorites, numerous organic remains were encountered; they included fragments of plankton, debris of tortoise shells, and coccoidal and filamentous bacteria-like formations. It is suggested that the phosphorites were formed due to the high local biological productivity over the outer edges of coral reefs and are not related to guano accumulation or to endoupwelling. 相似文献
798.
A short survey prepared by the Russian Commission on Atmospheric Radiation contains the most significant results of works in the field of atmospheric-radiation studies performed in 2007–2010. It is part of the Russian National Report on Meteorology and Atmospheric Sciences prepared for the International Association on Meteorology and Atmospheric Sciences (IAMAS). During this period, the Russian Commission on Atmospheric Radiation, jointly with concerned departments and organizations, ran the conference “Physics and Education,” dedicated to the 75th anniversary of the Department of Physics at St. Petersburg State University (2007); the International Symposium of CIS Countries “Atmospheric Radiation and Dynamics” (2009); and the 5th International Conference “Atmospheric Physics, Climate, and Environment” (2010). At the conferences, central problems in modern atmosphere physics were discussed: radiative transfer and atmospheric optics; greenhouse gases, clouds, and aerosols; remote methods of measurements; and new measurement data. This survey presents five directions covering the whole spectrum of investigations performed in the field of atmospheric radiation. 相似文献
799.
Comparative analysis of Rapana venosa (Valenciennes, 1846) from different biotopes of the Black Sea based on its morphological characteristics 总被引:1,自引:0,他引:1
A. R. Kos’yan 《Oceanology》2013,53(1):47-53
The Asian whelk Rapana venosa (Valenciennes, 1846) (Gastropoda: Neogastropoda: Muricidae), being tolerant to wide variations in the temperature, salinity, and oxygen concentration, successfully settled down in the Black Sea and eventually became one of the dominant species in the benthic ecosystems. The whelk inhabits all types of grounds all over the Black sea demonstrating a wide spectrum of morphological modifications. The objective of this research is to compare 10 samples of R. venosa from different biotopes of the Black Sea coast from the western Crimea to Sochi. The results of the statistical comparison based on 15 morphological characteristics showed that most of the samples differed from each other with high statistical significance (p < 0.001). The material fell into five groups on the discriminant analysis diagram corresponding to the biotope in which each was collected. The main ecological factor influencing the morphological variability of the rapa whelk populations is the characteristics of prey items they feed on, i.e., the bivalve species (Mytilus galloprovincialis, Anadara sp., Chamelea gallina), the prevailing prey size, and its abundance. 相似文献
800.
We analyze the influence of a rift in an ice field on the propagation of flexural gravitational waves in a basin of finite
constant depth. The ice cover is simulated by two floating semiinfinite elastic plates of different thickness. We studied
the dependence of the amplitude coefficients of reflection and transmission of waves incident on the rift on the frequency
of running waves, the thickness of ice on both sides of the rift, and the type of contact boundary conditions at the rift.
Translated by Peter V. Malyshev and Dmitry, V. Malyshev 相似文献