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81.
V. V. Zharkova N. S. Meshalkina L. K. Kashapova A. T. Altyntsev A. A. Kuznetsov 《Geomagnetism and Aeronomy》2011,51(8):1029-1040
The kinetics of beam electron precipitation from the top of a loop into the solar atmosphere with density gradients and an
increasing magnetic field have been generally described. The Fokker-Planck equations are solved with regard to Coulomb collisions
and the effect of the electric field induced by this beam. The photon spectra and polarization degree in hard X-ray (10–300
keV) and microwave (1–80 GHz) emissions are simulated under different assumptions regarding the beam electron distribution
function. The simulation results are compared with the flare observations on March 10, 2001, and July 23, 2002, visible at
different position angles. It has been indicated that the coincidence of the theoretical photon spectra with simultaneous
observations of the hard X-ray and microwave emissions of these flares is the best for models that not only take into account
collisions, but also the electric field induced by electron fluxes propagating in flare loops with very weakly or moderately
converging magnetic fields. 相似文献
82.
V. G. Kuznetsov 《Lithology and Mineral Resources》2011,46(2):186-197
Ch. Lyell’s works, the main work among which entitled Principles of Geology was published 180 years ago in 1830, created a new concept and laid the groundwork for modern geological science, methods
for the study of geological processes and geological history based on the investigation of recent environments and processes.
These propositions with natural corrections are also used in geological works at present. They have demonstrated persistence
of the geological history and absence of global geological catastrophes. This fact was of great importance in science and
ideology, because it changed basically the perception of the Earth’s nature and history based on the biblical world pattern. 相似文献
83.
V. S. Rakitin E. V. Fokeeva E. I. Grechko A. V. Dzhola R. D. Kuznetsov 《Izvestiya Atmospheric and Oceanic Physics》2011,47(1):59-66
The results of the carbon monoxide total content measurements over Moscow and Zvenigorod for 2005–2008 are compared with the same data sets for Moscow 1986–2005 and Beijing, 1992–2007. Two identical medium resolution diffraction spectrometers (resolution 0.2 cm?1) with solar tracking system were used. The CO total content measured simultaneously over the city and over Zvenigorod Scientific Station (ZSS) of the Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences (60 km west from Moscow). This method allows to isolate an urban part of CO content. The acoustic locator SODAR LATAN-3 measurements permitted us to study the influence of the carbon monoxide ventilation conditions upon level of pollution. Correlation coefficients between the urban part of CO content and average wind speed for cold and warm seasons were obtained. The data sets analysis showed a preeminent effect of the wind within boundary layer (up to 300 m) over the CO ventilation. The urban part of the CO content hasn’t increased in spite of more than quintuple increase of the motor-vehicles number in Moscow. An increase of the rural CO total column for the 1970–1985 has transformed into its virtually stable amount in between of 1986 to 2000, changed then to a decrease for 2001–2008. We noted the 2008 as “the year of the CO total column minimum” over the past decade. The effect of urban CO sources influence on the CO total column in rural area is small, i.e. on a level of 3% of the total number of measurements. The number of extremal daily values for Moscow is estimated as 5%, and 20% for Beijing. 相似文献
84.
V. G. Kuznetsov 《Doklady Earth Sciences》2011,441(2):1633-1636
Two branches of silica rockevolution related to oceans and continental blocks have been outlined. The boundaries of changes
in types of silica rocks, their formation, and development of the organic world were established: (i) the beginning of the
Phanerozoic was related to transformation from microbial to biogenic silica deposition (or to a change in the influence of
microbial activity on silica accumulation); (ii) cessation of the formation of cherts enriched in organic matter, which was
synchronized with land colonization by organisms in the Devonian, and (iii) an explosive style of global silica accumulation
related to the appearance and development of diatoms, which correlates with appearance of angiosperm plants in tropical forests. 相似文献
85.
N. B. Kuznetsov S. Yu. Orlov E. L. Miller A. V. Shazillo A. V. Dronov A. A. Soboleva O. V. Udoratina G. Gehrels 《Doklady Earth Sciences》2011,438(2):759-765
The first results of U/Pb isotopic dating (LA ICP MS) of detrital zircons from sands from the Middle Cambrian Sablinka Formation,
Upper Cambrian Ladoga Formation, Low Ordovician Tosna Formation, and calcareous sands from Syas’ Formation (Sargaevskii horizon
of the Upper Frasnian) from Baltica-Ladoga Glint (BLG) of the Southern Ladoga area are presented. The obtained ages of detrital
zircons span the intervals 492.7 ± 5.1-3196.4 ± 5.1 Ma (Sablino Formation); 577.9 ± 7–2972.6 ± 13.4 Ma (Ladoga Formation);
509.4 ± 8.5–3247.6 ± 10.1 Ma (Tosna Formation); 451.1 ± 14.7–2442.2 ± 6.9 Ma (Syas’ Formation). A comparison of the obtained
isotopic ages of detrital zircons to ages of crystalline complexes composing the Kola-Karelian, Svecofennian, and Sveconorwegian
domains of Baltic Shield and Pre-Uralian-Timanian structures of Subpolar and Polar Urals and basement of Pechora Basin was
carried out. It is proposed that the Middle Paleozoic sedimentary basin accumulated Upper Frasnian rocks of Syas’ Formation.
The basin ranged northward from the present-day BLG and occupied the eastern part of the Baltic Shield. 相似文献
86.
87.
88.
G. V. Ovchinnikova A. B. Kuznetsov I. M. Vasil’eva I. M. Gorokhov M. T. Krupenin B. M. Gorokhovskii A. V. Maslov 《Doklady Earth Sciences》2013,451(2):798-802
The Pb-Pb age of phosphorite concretions of the Zigaza-Komarovo Formation, which composes the intermediate horizons of the Riphean stratotype of the South Urals, was determined in fractions resulting from the stepwise dissolution of concretions in 0.1 N, 0.5 N, and 1 N HCl. The determination of the Sr isotopic composition in phosphate fractions was favorable for rejection the fractions polluted with extraneous material. On the 207Pb/204Pb-206Pb/204Pb diagram, the isochron based on 31 points corresponds to 1330 ± 20 Ma (MSWD = 1.12), which is in agreement with the stratigraphic position of the Zigaza-Komarovo Formation. The decreased μ2 value of 9.57 for the phosphorite concretions relative to that of the average earthly lead based on the Stacey-Kramers model (9.74) is related to the rocks with an admixture of mantle lead, which occur in the run-off area of the Zigaza-Komarovo sediments. 相似文献
89.
90.
V. F. Rudnitsky K. B. Aleshin A. Zh. Kuznetsov V. S. Ivanchenko 《Geology of Ore Deposits》2013,55(6):467-481
The structure of magnetite lodes is determined by iron and sulfur distribution, as well as texture and structure of ore. These features have been revealed by documentation of cores from ore intervals in exploration boreholes penetrating two main lodes 21 and 22 of the Estyunino iron deposit. The documentation of cores was accompanied by sampling for microscopic examination of texture and structure of ore and selection of Fe and S contents in ore. Then these data were summarized as sections of the lodes. It was established that the structure of magnetite lodes is characterized by conformable ore layers distinguished by texture, structure, and Fe and S contents. Banded and spotty ores containing less than 50% magnetite are predominant. Layers of homogeneous massive ore are infrequent. The textural pattern indicates a volcaniclastic nature of host rocks. The spotty texture is characteristic of hyaloclastites with vitreous shards. The banded texture with oriented distribution of fiamme is inherent to volcaniclastic rocks. In both cases, magnetite selectively replaces dark-colored vitreous fragments and is also dispersed in the salic matrix and lava fragments. No indications of crosscutting superposed relationships are observed. The available data can be satisfactorily explained by an impregnation-metasomatic mode of ore deposition. 相似文献