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1.
Malkov  O. Yu.  Avdeeva  A. S.  Kovaleva  D. A.  Nekrasov  A. D. 《Astronomy Reports》2022,66(7):526-534
Astronomy Reports - Distance dependences of interstellar extinction ( $${{A}_{V}}(d)$$ ) for a number of high-latitude areas of the southern sky were obtained using the data of the RAVE DR6...  相似文献   
2.
Doklady Earth Sciences - The phase relations upon eclogitization of basalt and melting of H2O-bearing eclogite were studied experimentally for basalt–H2O in the range of P = 3.7–4.0 GPa...  相似文献   
3.
Doklady Earth Sciences - Phase relations in the phlogopite–carbonate system were studied at P = 3.8 GPa and T = 1200–1300°C. The interaction of phlogopite with the carbonate melt...  相似文献   
4.
An improved method of two-dimensional kinematical structural analysis of tides (the “method of the orbits”) is presented. This method allows us to determine the parameters of the primary tidal waves shaping the observed tidal structure. The construction of the vertical orbits for the individual tidal harmonics is performed along the horizontal coordinate axes; one of them is oriented along the so-called “reactive azimuth,” which coincides with the direction of the tidal current at the instant of the zero tidal level. In this case, the orbit parameters include information on the amplitude-phase relations of the interfering waves and allow us to determine the angle of the waves crossing. The suggested method enables us to quantitatively describe the mechanism of the tidal formation with oblique interference both close to the shore and in the open sea. We tested the new method in two local zones of the White Sea (Morzhovets Island and in the vicinity of the entrance to Kandalaksha Gulf) where the presence of rotating semidiurnal tidal currents evidences the significant role of oblique interference of tidal waves. In these zones, the developed method made it possible to perform a detailed quantitative analysis of the local tide structure caused by the M2 tidal wave, which plays the dominant role in the White Sea. The result describes the structure of the propagation of the primary tidal waves better than the field of “pure” energy fluxes that was used earlier.  相似文献   
5.
We investigate analytically and numerically a nonlinear modification of the magnetospheric plasma density under the action of the ponderomotive force induced by ULF traveling waves, using the nonlinear stationary force balance equation. This equation is applied to both the dipole and dayside magnetosphere having one and two minima of the geomagnetic field near the magnetospheric boundary. The separate and joint actions of the ponderomotive, centrifugal, and gravitational forces on the density distribution are shown.  相似文献   
6.
A Ka-band backscatter model and an algorithm for measurement of the wind speed and direction over the sea surface by a frequency-modulated continous-wave radar demonstrator system operated in scatterometer mode have been developed. To evaluate the proposed algorithm, a simulation of the wind vector retrieval has been performed.  相似文献   
7.
8.
Nonlinear properties of the Pc1 geomagnetic pulsations with anomalous (magnetosonic) dynamic spectrum are studied. The nonlinear properties of the waves are reflected in the emergence of ponderomotive force proportional to the squared amplitude of the waves. Just as in the case of the Alfven waves, at small values of parameter ν0 = ω/ωci0 < 0.4 (ratio of the carrier frequency to proton gyrofrequency in the equatorial plane), the ponderomotive force leads to the modification of the background plasma through increasing its density towards the equator. At ν0 > 0.4, plasma is expelled from the equator towards the higher latitudes. The dependence of the nonlinear modification of background plasma for the different parameters of the magnetosphere is studied.  相似文献   
9.
We derive the expression for the ponderomotive force in the real multicomponent magnetospheric plasma containing heavy ions. The ponderomotive force considered includes the induced magnetic moment of all the species and arises due to inhomogeneity of the traveling low-frequency electromagnetic wave amplitude in the nonuniform medium. The nonlinear stationary force balance equation is obtained taking into account the gravitational and centrifugal forces for the plasma consisting of the electrons, protons and heavy ions (He+). The background geomagnetic field is taken for the dayside of the magnetosphere, where the magnetic field have magnetic “holes” (Antonova and Shabansky in Geomagn. Aeron. 8:639, 1968). The balance equation is solved numerically to obtain the nonlinear density distribution of ions (H+) in the presence of heavy ions (He+). It is shown that for frequencies less than the helium gyrofrequency at the equator the nonlinear plasma density perturbations are peaked in the vicinity of the equator due to the action of the ponderomotive force. A comparison of the cases of the dipole and dayside magnetosphere is provided. It is obtained that the presence of heavy ions leads to decrease of the proton density modification.  相似文献   
10.
The effect of the ponderomotive force on the background plasma modification near magnetic holes, which form at the dayside magnetospheric boundary under the action of the solar wind, has been studied. It was shown that this effect results in a substantial increase in a nonlinear plasma density disturbance. The dependence of the ponderomotive force on the magnetospheric parameters (the magnetic longitude, distance from the Earth’s surface, ratio of the wave frequency to the proton gyrofrequency, and ionospheric ion cyclotron wave amplitude) has been studied. Nonlinear plasma density disturbances will be maximal in the region of magnetic holes, which are located in the dayside magnetosphere at λ ~ 0°?30° geomagnetic longitudes (λ = 0° corresponds to noon), where the effect of the solar wind pressure is maximal. A similar effect is also observed in the dependence of a nonlinear plasma density disturbance on other magnetospheric parameters.  相似文献   
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