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31.
V. Ch. Zhukovsky K. G. Klimenko T. G. Khunjua 《Moscow University Physics Bulletin》2017,72(3):250-256
The phase structure of chiral-asymmetric matter has been studied within the (2 + 1)-dimensional quantum-field theory with the fermion–antifermion and fermion–fermion (or superconducting) channels of four-fermion interaction. For this purpose, the model takes both the chemical potential of the number of particles μ and the chiral chemical potential μ5 conjugated to the difference between the numbers of right and left fermions into account. A series of phase diagrams was plotted for different chemical potentials. It is shown that the chemical potential μ promotes the appearance of a superconducting phase, while an increase in the chemical potential μ5 suppresses the effect of the chemical potential μ on a system. The results of this study may be of interest for high-energy physics, condensed matter physics and, in particular, graphene physics. 相似文献
32.
Natalya N. Smirnova Tatiana G. Kulagina Larisa A. Smirnova Alla E. Mochalova Lyudmila Ya. Tsvetkova Ya. S. Samosudova Maksim B. Kiseliov Evgeny V. Sevast’yanov 《Journal of Thermal Analysis and Calorimetry》2013,112(3):1447-1452
For the first time, the heat capacity $ C_{\text{p}}^{^\circ } $ of poly(2-ethylhexyl acrylate) has been studied in an adiabatic vacuum calorimeter between 7 and 350 K, the standard thermodynamic functions: heat capacity $ C_{\text{p}}^{^\circ } $ (T), enthalpy H°(T) ? H°(0), entropy S°(T) ? S°(0), Gibbs function G°(T) ? H°(0) have been calculated from T → 0 to 350 K. The energy of combustion Δc U of the compound under study has been measured in a calorimeter with a stationary bomb and an isothermal shell. The standard enthalpy of combustion Δc H° and thermodynamic parameters of formation—enthalpy Δf H°, entropy Δf S°, Gibbs function Δf G°—at T = 298.15 K have been calculated. The results have been used to calculate the thermodynamic characteristics of 2-ethylhexyl acrylate bulk polymerization into poly(2-ethylhexyl acrylate) over the range from T → 0 to 350 K. 相似文献
33.
Milutka M. S. Burlov A. S. Vlasenko V. G. Koshchienko Yu. V. Korshunova E. V. Uraev A. I. Trigub A. L. Zubenko A. A. Klimenko A. I. Gusev A. N. 《Russian Journal of General Chemistry》2022,92(7):1297-1308
Russian Journal of General Chemistry - Azomethines were synthesized from 2,4,6-trimethylaniline, salicylaldehyde, and its 3(5)-halogen derivatives, as well as their complexes with zinc(II) (ZnL2).... 相似文献
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V. B. Petkov E. V. Bugaev P. A. Klimai M. V. Andreev V. I. Volchenko G. V. Volchenko I. M. Dzaparova D. D. Dzhappuev A. N. Gaponenko Zh. Sh. Guliev N. F. Klimenko A. U. Kudzhaev A. V. Sergeev N. S. Khaerdinov A. B. Chernyaev A. F. Yanin 《Journal of Experimental and Theoretical Physics》2010,110(3):406-416
The energy spectra and temporal characteristics of high-energy gamma-ray bursts from evaporating primordial black holes have been calculated using various evaporation models. The currently existing theoretical uncertainties in the shape of the evaporated photon spectrum are discussed. The data from the Andyrchy and Carpet-2 arrays of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) obtained in the mode of detection of a single cosmic-ray component are used to search for cosmic gamma-ray bursts with a primary photon energy of about 8 GeV. New upper limits have been obtained for the number density of evaporating black holes in a local region of space with a characteristic size of ~10?3 pc for various evaporation models. 相似文献
36.
M. V. Klimenko V. V. Klimenko F. S. Bessarab Yu. N. Korenkov E. V. Rozanov T. Reddmann I. E. Zakharenkova M. V. Tolstikov 《Russian Journal of Physical Chemistry B, Focus on Physics》2016,10(1):109-116
Sudden stratospheric warming (SSW) is a unique atmospheric phenomenon, which consists in a rapid rise of temperature at altitudes of ~30–40 km in high latitudes of the winter, typically, northern hemisphere. Modeling SSW effects in the mesosphere, thermosphere, and ionosphere is a challenging problem, because it must be done on a global scale, with consideration of numerous physical and chemical processes. This paper reports the results of calculations of the characteristics of total electron content (TEC) perturbations for the conditions of the SSW event in January 2009. The calculations are performed using the Global Self-Consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP) supplemented by the lower boundary conditions in the form of space–time distributions of the basic parameters of the mesosphere at an altitude of 80 km, as calculated by the SOCOL, KASIMA, and TIME GCM models. The simulation results show that, for some versions, the spatial distribution of total electron content disturbances ΔTEC shows a qualitative agreement with experimental data; however, the values of ΔTEC in all variants of calculations proved to be an order of magnitude lower than the measured. 相似文献
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39.
Recently Gehring, Gilman, and Martin introduced an important class of two-generator groups with real parameters:
whereβ=tr2
f−4,β′=tr2
g−4, and γ=tr(fgf
−1
g
−1)−2. The groups that belong to this class we callRP groups. We find criteria for discreteness ofRP groups generated by a hyperbolic element and an elliptic one of even order with intersecting axes.
The research was partially supported by the Russian Foundation for Basic Research (Grant 99-01-00630). 相似文献
40.
E. A. Gastilovich S. A. Serov N. V. Korol’kova V. G. Klimenko G. Rauhut 《Optics and Spectroscopy》2002,92(4):524-531
The squared dipole moments (P 0R )2 of vibronic transitions caused by vibronic-spin-orbit coupling along the coordinates of out-of-plane vibration modes R were calculated for the triplet ππ* electronic states (with u and g types of orbital symmetry) in a 1,3,6,8-tetrachlorodibenzo-p-dioxin (αβTCDD) molecule. Special features of distribution (P 0R )2 over R related to transitions from various sublevels of triplet states are ascertained. The obtained data made it possible to infer that the observed fine-structure phosphorescence spectrum of an αβTCDD solid solution corresponded to the 3 A g →S 0 and to eliminate a certain ambiguity in interpreting the vibronic structure of this spectrum. 相似文献