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991.
The structure of the averaged plasma pressure distribution in the plasma ring around the Earth at geocentric distances of
∼6–10R
E
has been determined. The distribution function moments measured on the international THEMIS mission satellites have been
used. The plasma pressure distribution in the equatorial plane at 15R
E
> XSM > −15R
E
and 15R
E
> YSM > −15R
E
has been statistically studied. The radial dependence of the plasma pressure at the day-night and morning-evening meridians
has been analyzed. It has been indicated that the plasma ring around the Earth has a structure, which is close to being azimuthally
symmetric. The achieved results have been compared with the pressure distributions obtained previously. It has been indicated
that in the overlapping regions, the achieved results agree with the previously obtained data within the pressure determination
errors. 相似文献
992.
The condensation process of water vapors in the exhaust plume of a rocket engine in the upper atmosphere is considered. We take into account the processes of particle heating during the release of latent heat of condensation, radiative heating, and energy losses to emission. From the solution of the equations of thermal balance and mass balance of condensing particles, we obtained the time dependences of variations in temperature and particle sizes. In the process of condensation, the thickness of the ice layer on particles may reach >70 Å. 相似文献
993.
We have estimated the variations in the atmospheric electrostatic field (AEF, E
Z(0)) strength in the surface layer caused by variations in conductivity due to radon influences, cosmic ray intensity, changes
in the balance of light and heavy ions during sunset and sunrise, and under the effect of the ionospheric electric current
potential on the AEF potential. It is shown that the air conductivity varies due to ionization under the effect of radon emanations
and is determined by the radon exhalation and turbulent diffusion of the surface air layer, while the cosmic ray intensity
affects the surface air conductivity through changes in the ion recombination conditions. A decrease in the air conductivity
due to a decrease in the cosmic ray intensity (Forbush decrease) also decreases E
Z(0), while a decrease in radon fluxes results in an increase in E
Z(0). We have estimated the effect of illumination conditions on the AEF due to variations in the relative concentration of heavy
and light ions under the influence of photodetachment and photoattachment processes. The work has been done on the basis of
data received from the Paratunka observatory (Kamchatka). 相似文献
994.
The dispersion of exhaust products of rocket fuel in the direction perpendicular to the motion of a rocket is investigated
in this work. A comparison of the results of numerical calculations with a self-similar approximation of a strong cylindrically
symmetric explosion is fulfilled. It is shown that at sufficiently high rocket velocity V
∞, which exceeds the sum of gas exhaust velocity V
e
from the nozzle and sound speed V
s
(V
∞ > V
e
+V
s
), a gasdynamic hole can arise around the rocket trajectory in the upper atmosphere, inside which the total concentration
of gas becomes less than the equilibrium concentration of gas at a given altitude. The dynamics of the profiles of density
and temperature of the exhaust products inside a rocket plume is calculated. 相似文献
995.
V. K. Korotkov M. D. Berkova A. V. Belov E. A. Eroshenko P. G. Kobelev V. G. Yanke 《Geomagnetism and Aeronomy》2011,51(2):247-253
This paper describes a method, which makes it possible to eliminate the effect of snow cover from the neutron component of
secondary cosmic radiation. For many circumpolar, high-latitude, and mountain stations, where cosmic rays are continuously
registered, it is exclusively important to take the presence of snow into consideration. Comparisons are made for manual and
automated measurements, which are corrected for the snow effect based on the developed algorithm. The described method was
tested for a number of cosmic ray stations where considerable snow masses are accumulated during the winter period near or
above a detector: Magadan, Mount Hermon, Jungfraujoch, and Nain. 相似文献
996.
P. A. Bespalov 《Geomagnetism and Aeronomy》2011,51(2):226-233
Different types of natural electromagnetic emissions are generated in the Earth’s electronic radiation belts. The conditions
for generation of these emissions depend on the plasma parameters, geometry of the system, wave transfer processes, and regularities
of particle accumulation and precipitation from the magnetic trap. Effective interaction between waves and particles can often
be described by the plasma magnetospheric maser theory. A plasma magnetospheric maser actually operates in several main regimes.
These regimes are responsible for the generation of VLF emissions with different frequency spectrum dynamics. The regimes
replace each other as a result of variations in the local and global characteristics of the magnetosphere. For example, the
cyclotron generation dynamics largely depends on the the source power of energetic particles. Several new methods for diagnosing
the near-Earth plasma can be implemented if the plasma magnetospheric maser theory is known. 相似文献
997.
Using three radio techniques for determining the spatial and terminal distribution of the electron concentration in the ionospheric
F region, a number of parameters of medium-scale travelling ionospheric disturbances (the effective thickness of the atmospheric
waveguide and height of its axis, spatial and time periods, propagation speeds, and maximum amplitudes of the disturbances)
are determined. 相似文献
998.
The distributions of the natural noise electromagnetic field level in the vicinity of the first Schumann resonance have been
studied based on data from Lovozero observatory (the Kola Peninsula). Daily curves of noise level excesses over specified
thresholds at different geomagnetic disturbances have been constructed. It has been indicated that the curves are morphologically
similar on magnetically quiet days but are highly variable from day to day, although the averaged curves are similar in some
characteristics to the unitary variation in the surface quasistatic electric field. The possibilities of applying the known
formula for the probability distribution of the VLF atmospheric radio noise amplitude in order to analytically describe the
noise level probability distribution have been considered. It has been detected that geomagnetic disturbances pronouncedly
affect the distribution parameters, sharply increasing the amount of large-amplitude noise. 相似文献
999.
N. G. Kleimenova O. V. Kozyreva M. Kubicki S. Michnowski 《Geomagnetism and Aeronomy》2011,51(3):394-401
This paper studies time variations in the near-ground atmospheric electric field (Ez) at the geomagnetic latitude of 74° (Hornsund observatory) during polar substorms. Ez variations are compared with those in the potential drop across the polar cap (Up), according to SuperDARN radar observations. It is found that in the morning sector, time variations in Ez are strongly driven by time variations in the electrojet and almost do not depend on time variations in Up, which is presumably due to the penetration of the electric field of the electrojet into tropospheric altitudes. 相似文献
1000.
This article considers the process of entry of cosmic substance into the Earth’s atmosphere and the further evolution of the
formed extraterrestrial aerosol. It is shown that meteorite-derived aerosol generated in the atmosphere may affect the Earth’s
climate in two ways: (a) particles of meteoric haze may serve as condensation nuclei in the troposphere and stratosphere;
(b) charged meteor particles residing in the mesosphere may markedly change (by a few percent) the total atmospheric resistance
and, thereby, affect the global current circuit. Changes in the global electric circuit, in turn, may influence cloud formation
processes. The obtained results argue for the fact that the meteoric dust in the Earth’s atmosphere is potentially one of
the important climate-forming agents. It is shown that the amount of interstellar dust in the Earth’s atmosphere is too small
to have a considerable affect on atmospheric processes. 相似文献