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101.
Parkerite and bismutohauchecornite in chromitites of the Urals: Example of the Uralian Emerald Mines
An unusual ore mineralization represented by parkerite, millerite, bismutohauchecornite, bismuthinite, and nickeline was registered in altered chromitite from the Mariinsk emerald–beryllium deposit. Such mineralization is typical of Cu–Ni sulfide ores and hydrothermal veins from the five-element formation. This mineral assemblage was not registered in ophiolitic ultrabasic rocks and related chromitites. The find of bismutohauchecornite is the first in the Urals; the find of parkerite is the third. 相似文献
102.
A review and comparative analysis of results from studies of the effects of scattering on the interstellar medium using giant pulses of the Crab Nebula pulsar (B0531+21) are presented. This analysis was based on eight epochs of Very Long Baseline Interferometry (VLBI) radio observations carried out as part of the scientific program of the Radio Astron mission during 2011–2015. The scintillation timescale t scint and spectral index γ for the power-law energy distribution of the pulses were obtained for each observing epoch. The measured scintillation timescales are t scint = 7.5?123 s at 1668 MHz and t scint = 2.9 s at 327 MHz. The spectral indices are ?1.6...?2.5. The frequency and time characteristics of the scattering were measured using two independent methods: based on the decorrelation bandwidth Δν d and the scattering timescale τ SC. The angular size of the scattering disk θ H of the pulsar was obtained, the phase structure functions constructed, and the distance to the effective scattering screen estimated. The derived diameter of the scattering disk θ H at 1668 MHz ranges from 0.4 to 1.3 mas, while the scatteringdisk diameter at 327 MHz is 14.0 mas. The measured distance to the effective scattering screen ranges from 0.7 to 1.9 kpc, and varies from observation to observation in the same way as the scattering timescale and decorrelation bandwidth: τ SC ≈ 0.9?5.8 μs and Δν d ≈ 40.7?161 kHz at 1668 MHz. The scattering timescale and decorrelation bandwidth at 327 MHz are 2340 μs and 68 Hz. 相似文献
103.
E.?S.?ZhitovaEmail author M.?P.?Popov S.?V.?Krivovichev A.?N.?Zaitsev N.?S.?Vlasenko 《Geology of Ore Deposits》2017,59(8):745-751
The paper describes the first finding of quintinite [Mg4Al2(OH)12][(CO3)(H2O)3] at the Mariinsky deposit in the Central Urals, Russia. The mineral occurs as white tabular crystals in cavities within altered gabbro in association with prehnite, calcite, and a chlorite-group mineral. Quintinite is the probable result of late hydrothermal alteration of primary mafic and ultramafic rocks hosting emerald-bearing glimmerite. According to electron microprobe data, the Mg: Al ratio is ~2: 1. IR spectroscopy has revealed hydroxyl and carbonate groups and H2O molecules in the mineral. According to single crystal XRD data, quintinite is monoclinic, space group C2/m, a =5.233(1), b = 9.051(2), c = 7.711(2) Å, β = 103.09(3)°, V = 355.7(2) Å3. Based on structure refinement, the polytype of quintinite should be denoted as 1M. This is the third approved occurrence of quintinite-1M in the world after the Kovdor complex and Bazhenovsky chrysotile–asbestos deposit. 相似文献
104.
105.
P.L. Popov 《Geography and Natural Resources》2010,31(4):385-389
The birthplace differentiation for representatives of different groups of the Russian elite is considered for macroregions, subjects of the RF and cities. It is shown that in the elite groups under consideration, the proportions of natives of Moscow and St. Petersburg exceed several times the proportions of natives of these cities in the country's population. The other large cities, especially Yekaterinburg, Kazan, Chelyabinsk, Nizhni Novgorod, Ufa, Saratov, Voronezh, Irkutsk, Omsk, and Rostov-on-Don, are centers of elitogenesis vastly excelled by the two capital cities. The differences between macroregions without regard for Moscow and Saint Petersburg are significant in separate aspects of elitogenesis. 相似文献
106.
V. Bychkov M. V. Popov A. M. Oparin L. Stenflo V. M. Chechetkin 《Astronomy Reports》2006,50(4):298-311
We consider the motion of a bubble in a central acceleration field created by gravity or a centrifugal force. In the former case, the bubble moves outwards from and, in the latter, towards the center. We have calculated the characteristic time needed for a bubble to leave or reach the center. The solution obtained provides insight into the processes of thermonuclear supernovae and combustion; in other words, into the interaction between a flame and a turbulent vortex. In the case of combustion, a light bubble of burnt material propagates towards the axis of a strong turbulent vortex faster than it drifts in the direction of rotation of the vortex. It is expected that the development of bubbles should prevent the formation of “pockets” at the flame front, similar to those predicted by a simplified model of turbulent combustion in a constant density flux. In the case of a thermonuclear supernova in a deflagration burning regime, it is shown that light products of burning rise from the center of the white dwarf substantially more rapidly than the thermonuclear flame front propagates. As a result, a flame cannot completely burn the central part of the star, and instead is pushed to the outer layers of the white dwarf. The effect of bubble motion (large-scale convection) makes spherically symmetric models for thermonuclear supernovae unrealistic, which is of prime importance for the supernova spectrum and energy. The motion of bubbles is even faster in the case of a rotating white dwarf; under certain conditions, the centrifugal force may dominate over the gravitational force. To test this theory, we have carried out numerical simulations of supernovae explosions for various sizes of the burned region in the core of the presupernova. We have derived a relation between the rate of large-scale convection and the size of the burned region, which is specified by the rate of the deflagration in the thermonuclear burning. 相似文献
107.
I. P. Chunchuzov S. N. Kulichkov O. E. Popov V. G. Perepelkin 《Izvestiya Atmospheric and Oceanic Physics》2010,46(5):597-607
A wave theory of propagation of an acoustic pulse in a moving stratified atmospheric layer above the ground with a finite
impedance of an underlying ground surface is developed. The shapes of acoustic signals in a near-ground atmospheric waveguide,
which are formed due to temperature inversion and a vertical shear of the wind velocity, are calculated based on this theory.
These signals are compared with those measured during the experiments where vertical profiles of the wind velocity and temperature
in an atmospheric boundary layer have been continuously controlled using a sodar, a temperature profile meter, and acoustic
anemometers or thermometers mounted on a 56-meter-high mast. The joint action of a near-ground acoustic waveguide, the impedance
of the underlying surface, and a vertical layered structure of the boundary atmospheric layer on a signal shape far from the
acoustic source are studied. 相似文献
108.
109.
110.
The cumulative applied climate indices SAT and SET used in the Russian literature are considered in detail. These indices differ in calculation methods and, consequently, their values differ in different regions. The example is presented of the incorrect use of these indices by some authors for studying biological objects which leads to false conclusions. The method of calculation of the foreign applied climate index GDD is given. This index corresponds to the Russian index SET, and its interpretation as a counterpart of SAT is wrong. 相似文献