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71.
Knyazev E. V. Bolotov V. V. Ivlev K. E. Povoroznyuk S. N. Kan V. E. Sokolov D. V. 《Physics of the Solid State》2019,61(3):433-439
Physics of the Solid State - The morphology, structure, and electrophysical characteristics of multiwall carbon nanotubes (MWCNTs), as affected by defects induced by ion bombardment, are studied... 相似文献
72.
Crystallography Reports - The influence of a dc magnetic field on the motion of growth dislocations with a density of (0.7–7.0) × 104 cm–2 and the electron density in the range of... 相似文献
73.
Andrew V. Knyazev. 《Mathematics of Computation》1997,66(219):985-995
The following estimate for the Rayleigh-Ritz method is proved:
Here is a bounded self-adjoint operator in a real Hilbert/euclidian space, one of its eigenpairs, a trial subspace for the Rayleigh-Ritz method, and a Ritz pair. This inequality makes it possible to analyze the fine structure of the error of the Rayleigh-Ritz method, in particular, it shows that if an eigenvector is close to the trial subspace with accuracy and a Ritz vector is an approximation to another eigenvector, with a different eigenvalue. Generalizations of the estimate to the cases of eigenspaces and invariant subspaces are suggested, and estimates of approximation of eigenspaces and invariant subspaces are proved.
74.
A. A. Knyazev A. S. Krupin K. A. Romanova Yu. G. Galyametdinov 《Journal of Coordination Chemistry》2016,69(9):1473-1483
Highly fluorescent blends based on PVK (poly(N-vinylcarbazole)) doped by a new greatly anisometric Eu(III) mesogenic complex were described. The structure of the ligands in the complex was selected in such a way that its absorption maximum was close to the emission maximum of the polymer. The full-energy transfer conditions in the conjugated polymer–lanthanide complex blends were revealed. Improving luminescence efficiency of the blend occurs due to an increase in the threshold concentration of the emitting ions to prevent self-quenching phenomena. The resulting relative luminescence quantum yield of the blend increases more than twice in comparison with the individual complex. The optimized blends may be promising for application as red emitters for OLED, etc. 相似文献
75.
E. P. Ivakhnenko Yu. V. Koshchienko P. A. Knyazev V. B. Nalbandyan K. A. Lyssenko I. V. Ananyev A. S. Bogomyakov V. I. Minkin 《Russian Journal of Coordination Chemistry》2016,42(4):252-259
The six-coordinate cobalt complexes, C57H63.50N4.50O4Co (IIa), C60H69N5O4Co (IIb), C58H67N3O8Co (IIc), C56H61N5O10Co (IId), C56H63N3O6Co (IIe), C58H66N4O6Co (IIf), and C58H63N7O8Co (IIg), adducts of high-spin tetrahedral Co(II) bis(salicylaldiminates) (C29H24.50N3.50O2Co (Ia), C32H30N4O2Co (Ib), C30H28N2O6Co (Ic), C28H22N4O8Co (Id), C28H24N2O4Co (Ie), C30H27N3O4Co (If), and C30H24N6O6Co (Ig)) and redox-active 2,4,6,8-tetrakis(tert-butyl)phenoxazin-1-one (L), were synthesized and studied for structure and magnetic properties. Complexes IIa–IIg have octahedral structure (CIF files CCDC nos. 1403920 (IIf), 1403922 (IIg)) and exist in the ground low-spin state (ls-CoIII-SQ), which arises upon intramolecular single-electron redox process in the ligand–metal system. The presence of substituents of different nature in the azomethine ligands of IIa–IIg does not induce any significant changes in their magnetic properties. 相似文献
76.
Yu. V. Knyazev A. V. Lukoyanov Yu. I. Kuz’min S. Gupta K. G. Suresh 《Journal of Experimental and Theoretical Physics》2016,123(4):638-642
The electronic structure and the optical properties of the HoCoSi and ErNiSi compounds are studied. Spin-polarized band calculations are performed in the local electron density approximation corrected for the strong electron–electron interactions in the 4f shell of a rare-earth ion (LSDA + U method [11]). The optical constants are measured by ellipsometry in a wide wavelength range, and the frequency dependences of a number of spectral parameters are determined. The calculated densities of states are used to interpret the structural features of the interband optical conductivities of the intermetallic compounds. 相似文献
77.
Knyazev VD 《The journal of physical chemistry. A》2007,111(19):3875-3883
Molecular dynamics modeling of C-C bond dissociation is performed for a series of linear alkanes and polyethylene macromolecules with the chain lengths ranging from one to a thousand constituent ethylene monomers (PE-1-PE-1000). The rate constants obtained in molecular dynamics calculations are compared with those determined using variational transition state theory with the same potential energy surface. The results of simulations demonstrate a significant accelerating effect of chain length on the rates of C-C bond scission. Per-bond rate constant values increase with the increasing chain length, up to an order of magnitude, in the sequence of linear alkanes from PE-1 (ethane) to PE-5 (decane); this dependence becomes saturated for longer chain lengths. Stiffening the potentials of bending and especially the torsional degrees of freedom diminishes the accelerating effect of chain length, while constraining the bond distances for all C-C bonds except the one undergoing dissociation has no effect. The results of the calculations are compared with existing experimental data on the dependences of the rates of thermal decomposition of linear alkanes on the alkane chain length. 相似文献
78.
V. E. Korsukov S. A. Knyazev P. N. Butenko V. L. Gilyarov M. M. Korsukova I. A. Nyapshaev B. A. Obidov 《Physics of the Solid State》2017,59(2):316-320
A change in the surface morphology of recrystallized tungsten foil under the effect of uniaxial tension in ultrahigh vacuum is studied by low-energy electron diffraction and atomic force microscopy. It is found by using low-energy electron diffraction that on the foil surface consisting of separate blocks with dominant face (112), there is a turn in orientation of the structural blocks. The analysis of the topograms of different areas of the side surface of a broken sample, obtained by atomic force microscopy, enabled the association of changes in the atomic structure of the surface layers of foil with a change in its relief by mechanical action. 相似文献
79.
Ellipsometric investigations of the optical properties of Ru2Ge3 and Ru2Sn3 intermetallic compounds are carried out in the wavelength range from 0.22 to 15 μm. The nature of interband light absorption is analyzed based on a comparative analysis of the experimental and theoretical frequency dependences of an optical conductivity. The obtained results confirm the existence of energy gaps at the Fermi level in the electronic spectra of these materials predicted earlier by the band-structure calculations. 相似文献
80.
L. A. Dobrun A. P. Kovshik E. I. Ryumtsev Yu. G. Galyametdinov A. A. Knyazev 《Optics and Spectroscopy》2017,122(5):813-815
The values of optical anisotropy of two series of thermotropic nematic liquid crystalline complexes based on the ions Eu+3, Gd+3, Tb+3, and Dy+3 have been determined. Even–odd alternation of optical anisotropy with an increasing number of protons in ions of lanthanides has been observed. It is established that, in the considered series of lanthanidomesogens, optical anisotropy is more sensitive to changes in the ligand structure of complexes than to the variation of the complexing agent. 相似文献