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901.
902.
Baohe Yuan Xiansheng Liu Wenbo Song Yongguang Cheng Erjun Liang Mingju Chao 《Physics letters. A》2014
Fe3+-doped ZrV1.6P0.4O7 with Fe:Zr molar ratios of 1:9, 2:8, 3:7 and 4:6 was synthesized to reduce phase transition and obtain low thermal expansion. It is shown that the phase transition temperature of Fe-doped ZrV1.6P0.4O7 is reduced obviously with increasing the content of Fe. Fe3+ ion with lower valence and smaller radius than that of Zr4+ favors to extend the bond angle of V–O–V(P) close to 180° in ZrV1.6P0.4O7, which is considered responsible for the normal structure at room temperature and low thermal expansion. The thermal expansion coefficients of Fe-doped ZrV1.6P0.4O7 for Fe:Zr molar ratios from 1:9 to 4:6 are calculated to be from −4.33×10−6 to 5.2×10−7 K−1 by linear thermal expansion measurement. The effect of small amount of FeV0.8P0.2O4 formation with higher content of Fe3+ on thermal expansion coefficients of the samples is discussed. 相似文献
903.
《Physics letters. A》2014,378(1-2):65-67
We theoretically propose a structure that the population inversion between the Landau levels (LLs) of the graphene can be achieved by the electrical injection. This structure may be used for the Landau level-laser and related infrared and terahertz emitters. We mainly study the linewidth of the optical transitions between LLs in graphene due to the electron–acoustic phonon scattering. Within the Huang–Rhysʼs lattice relaxation model, we improve the effective single-phonon mode (ESM) for the acoustic phonon to calculate the linewidth of the optical transition and compare the obtained results with that of in the low and high-temperature limit. We find that the ESM provides a very good approximation for the temperature dependence of linewidth, which covers the dominating features of the low and high-temperature limit. 相似文献
904.
We study the phase separation dynamics in finite lifetime systems. Particles created by the external fields are unstable and decay within the finite lifetime. Effects of the particle lifetime and the interparticle interaction for the phase separation dynamics are discussed. In our theory, the formulation is based on the coarse-grained lattice gas model. As a result, effects of the finite lifetime are that the phase separation is restrained and that the finite size of domains remain finally at t = X . 相似文献
905.
Abstract Single crystals of (Sb0.75Bi0.25)2-xMnxTe3 (x = 0.0–0.05) were characterized by X-ray diffraction, measurements of reflectance in the plasma resonance frequency region, Hall coefficient, electrical conductivity, and Seebeck coefficient. It was found that Mn atoms in the crystal structure of Sb1.5Bi0.5Te3 behave like acceptors; the increase in the hole concentration is explained by the formation of substitutional defects of Mn'Sb and Mn'Bi in the crystal lattice of the studied crystals. 相似文献
906.
Dimitri Mavriplis 《International Journal of Computational Fluid Dynamics》2013,27(8):613-620
This paper discusses advances in two areas which may have the potential to impact future simulation capabilities through advanced algorithms. This includes spectral multigrid (MG) solvers for high-order accurate spatial discretizations and efficient MG solvers for kinetic-based schemes. Preliminiary evidence is given illustrating the promise of these approaches for application to engineering simulations. 相似文献
907.
A vibrational study of ACu3Fe4O12 (A = Ca, Sr, Y and Eu) compounds was carried out by means of micro-Raman scattering and lattice dynamics calculations. Polarized Raman scattering measurements were performed on rectangular microcrystals, with sizes close to 7 μm, and six Raman active modes were observed among the eight expected. It was then possible to assign the observed modes to the correct symmetry. Moreover, lattice dynamics calculations led to determine the main atomic displacements and a good agreement was found between experimental and theoretical wavenumbers. Furthermore, wavenumbers evolution versus A cation showed two behaviors separating the samples into two groups. 相似文献
908.
《Journal of Physics and Chemistry of Solids》2014,75(8):1004-1009
A series of static lattice calculations were performed to determine the site selectivity of cations of differing size and valence when substituted onto the Ca sites of the calcium chlorosilicate (Ca3(SiO4)Cl2) lattice, a potential host phase for the immobilisation of halide-rich wastes arising from the pyrochemical reprocessing of plutonium. Atomic-scale simulations indicate that divalent cations are preferentially substituted onto the Ca1 site, whilst tri- and tetravalent cations are preferentially hosted on the Ca2 site, with the Ca1 site favoured for forming the vacancies necessary to charge-balance the lattice as a whole. Multi-defect calculations reveal that the site selectivity of the dopant cations is dependent on their ionic radii; as the ionic radii of the divalent cations increase, substitution onto the preferred site becomes more and more strongly favoured, whereas the inverse is true of the trivalent cations. 相似文献
909.
In this paper,we initiate a study of S-fuzzy ideal(filter) of a lattice where S stands for a meet semilattice.A S-fuzzy prime ideal(filter) of a lattice is defined and it is proved that a S-fuzzy ideal(filter) of a lattice is S-fuzzy prime ideal(filter) if and only if any non-empty α-cut of it is a prime ideal(filter).Stone's theorem for a distributive lattice is extended by considering S-fuzzy ideals(filters). 相似文献
910.
Our main objective is to study properties of a fuzzy ideals(fuzzy dual ideals).A study of special types of fuzzy ideals(fuzzy dual ideals) is also furnished.Some properties of a fuzzy ideals(fuzzy dual ideals) are furnished.Properties of a fuzzy lattice homomorphism are discussed.Fuzzy ideal lattice of a fuzzy lattice is defined and discussed.Some results in fuzzy distributive lattice are proved. 相似文献