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31.
Condensation of water vapor and carbon dioxide in the jet exhausts of rocket engines during last stages of Proton, Molniya, and Start launchers operating in the upper atmospheric with different types of fuels is considered. Particle heating is taken into account with emission of latent heat of condensation and energy loss due to radiation and heat exchange with combustion products. Using the solution of the heat balance and condensed particle mass equations, the temporal change in the temperature and thickness of the condensate layer is obtained. Practically, no condensation of water vapor and carbon dioxide in the jet exhaust of a Start launcher occurs. In plumes of Proton and Molniya launchers, the condensation of water vapor and carbon dioxide can start at distances of 120–170 m and 450–650 m from the engine nozzle, respectively. In the course of condensation, the thickness of the “water” layer on particles can exceed 100 Å, and the thickness of carbon dioxide can exceed 60 Å. 相似文献
32.
V. S. Semenov S. V. Semenov V. M. Savatenkov V. N. Dech V. A. Glebovitsky 《Geology of Ore Deposits》2017,59(8):687-706
The study of the Lukkulaisvaara layered massif from the Olang group of intrusions in northern Karelia corroborates the important role of supplementary intrusive phases of PGE mineralization. Injection and crystallization of new magma portions result in (1) the formation of potholelike depressions within intrusion and (2) a return to high-temperature olivine-bearing mineral assemblages in the mafic part of section. PGM formation is accompanied by crystallization of secondary minerals in a wide range of temperatures and pressures. To provide insight into these problems, a geochemical study of Nadezhda area has been performed and new data obtained for the distribution of isotopes in the Rb–Sr, Pb–Pb, and Sm–Nd systems. 相似文献
33.
34.
Yasyukevich V. V. Kazakova E. V. Popov I. O. Semenov S. M. 《Doklady Earth Sciences》2009,427(2):1030-1034
Possible changes in the area inhabited by the ticks Ixodes ricinus and Ixodes persulcatus, the main transmitters of tick-borne encephalitis and Lyme disease in Russia, caused by temperature changes in 1976–2005
compared to 1946–1975 are discussed. It is shown that these changes could result in some areal expansion of these species.
In the European part of Russia, I. ricinus expanded its areal boundaries to the east 100–300 km. I. persulcatus expanded its areal in the Asian part of Russia. Its boundary moved to the north and northeast 100–300 km. Areal expansion
both of species has not been observed. 相似文献
35.
Induced magnetic fields in the Earth arise due to two phenomena: induction generated by the time-variable exciting field and the motional induction caused by movement of the conductive planet in the outer magnetic fields. The comparison of both approaches on the spherical Earth has been analyzed in the present work for two sources in the ionosphere and magnetosphere. For this aim, both sources with their natural sizes and positions have been modeled analytically to obtain the fields on the layered sphere at the middle latitudes. The conditions when the steady ring current field is not influenced by the Earth’s rotation have been established theoretically. The synthetic diurnal magnetograms were used for the deep sounding by the magnetovariation spatial gradient method and the result was compared with the one obtained on the nonrotating sphere. Sounding results using both approaches were found different above the 2D inhomogeneous mantle. The precessions of the magnetospheric belt current pole for daily sampling frequency were presented using several geomagnetic observatory data in the northern hemisphere. 相似文献
36.
M. V. Charykova V. G. Krivovichev O. S. Yakovenko V. V. Semenova K. N. Semenov W. Depmeier 《Geology of Ore Deposits》2012,54(8):638-646
The understanding of the mechanisms of the selenium behavior under near-surface conditions is an urgent problem of modern mineralogy and geochemistry, and is very important for solving environmental problems. The objective of this study is to synthesize analogs of ahlfeldite and cobaltomenite and to estimate their solubility in water. These analogs have been synthesized by mixing aqueous solutions of cobalt and nickel nitrates, respectively, and sodium selenite acidified with a solution of nitric acid. The obtained samples have been identified by X-ray diffraction and IR spectroscopy. The solubility has been determined by the isothermal saturation method in ampoules at 25°C, while the solubility products have been calculated using the Geochemist’s Workbench (GMB 7.0) software package. The solubility products of ahlfeldite and cobaltomenite are 10?9.20 and 10?9.44, respectively. The Eh-pH diagrams were calculated and plotted with the GMB 7.0 software package. The Eh-pH diagrams of the Ni-Se-H2O and Co-Se-H2O systems have been calculated for the average contents of these elements in underground water and their contents in acidic water of the oxidation zone of sulfide deposits. The formation of ahlfeldite and cobaltomenite under near-surface conditions is discussed. 相似文献
37.
The hourly data of nine geomagnetic observatories situated in Central Europe have been analyzed using the generalized magnetovariation
(GMV) method designed recently for induction soundings of inhomogeneous media. In this method, impedance is one of transfer
functions in the differential relation between spectra of the magnetic components and their derivatives. The peculiarity of
this impedance is its correspondence to the magnetotelluric one estimated from the linear relations. Three transfer functions
have been estimated simultaneously for data of geomagnetic observatories, using three different routines working in the period
range from three hours up to two days. Noises in the source field components have been compared with noise in the estimated
plane field divergence. The multivariate errors-in-variables method was used to extract spatially and temporally coherent
geomagnetic field structure from the partially incoherent geomagnetic variations. This method allows estimating reliably impedances
and gradient tippers for each observatory, taking into consideration the Earth’s sphericity. The obtained responses have been
used for induction soundings and for detecting a deep inhomogeneity in the region. 相似文献
38.
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
39.
40.
M. V. Charykova V. G. Krivovichev O. S. Yakovenko V. V. Semenova K. N. Semenov W. Depmeier 《Geology of Ore Deposits》2013,55(7):525-531
Understanding the mechanisms of arsenic’s behavior under near-surface conditions is one of the actual problems of contemporary mineralogy and geochemistry and is important for solving environmental problems. The aim of this study is to synthesize analogs of erythrite and annabergite and to investigate their solubility in water. These phases have been synthesized by the boiling-dry of aqueous solutions of cobalt and nickel nitrates mixed with sodium hydroarsenate alkalized with NaOH. The samples obtained have been identified with electron microprobe, X-ray diffraction, and IR spectroscopy. Solubility has been determined by the isothermal saturation method in ampoules at 25°C. The solubility has been calculated using the Geochemist’s Workbench (GMB 7.0) software package. The measured solubilities of erythrite and annabergite are 10?35.76 and 10?36.43, respectively. Eh-pH diagrams were calculated and plotted using the GMB 7.0 software package. The database comprises the thermodynamic parameters of 46 elements, 47 main particles, 48 redox pairs, 552 particles in solution, 624 solid phases, and 10 gases. The Eh-pH diagrams of the Ni-As-H2O and Co-As-H2O systems were plotted for the average contents of these elements in the acidic waters in the oxidation zones of sulfide deposits. The formation of erythrite and annabergite under near-surface conditions is discussed. 相似文献