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991.
S.A. Mikhailov K. Ziegler 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(1):117-120
A floating Wigner crystal differs from the standard one by a spatial averaging over positions of the Wigner-crystal lattice.
It has the same internal structure as the fixed crystal, but contrary to it, takes into account rotational and/or translational
symmetry of the underlying jellium background. We study properties of a floating Wigner molecule in few-electron spin-polarized
quantum dots, and show that the floating solid has the lower energy than the standard Wigner crystal with fixed lattice points.
We also argue that internal rotational symmetry of individual dots can be broken in arrays of quantum dots, due to degenerate
ground states and inter-dot Coulomb coupling.
Received 12 September 2001 / Received in final form 24 April 2002 Published online 9 July 2002 相似文献
992.
The extension of two axioms due to Cook and Fischer to the category CAP of convergence approach spaces leads to the study of non-Archimedean approach spaces as well as two versions of regularity appropriate to CAP and related categories. 相似文献
993.
Coherent spectroscopy of semiconductor quantum dots, such as photon echo, accumulated photon echo, interferometric coherency measurement, quantum beat and coherent phonon measurement, are reviewed in relation to the historical progress in the coherent spectroscopy of semiconductors. 相似文献
994.
本文根据有限区间上Riemann积分的Arzela控制收敛定理[1],给出无穷限积分的控制收敛定理,并做了相应的推广。 相似文献
995.
996.
原子模型势理论中径向微分算符矩阵元的计算 总被引:1,自引:1,他引:0
本文推广[7,8]的工作,导出了多电子原子模型势理论中含径向微分算符的矩阵元通式,可直接用于以“速度”及“加速度”形式跃迁振子强度计算。 相似文献
997.
Kadyrzhanov K. K. Rusakov V. S. Turkebaev T. E. Vereschak M. F. Kerimov E. A. Plaksin D. A. 《Hyperfine Interactions》2002,141(1-4):453-457
Beryllium coating of the iron foil is made by means of magnetron sputtering. Mössbauer studies are performed by means of two registration techniques: conversion electron Mössbauer spectroscopy (CEMS) and the γ-ray technique in absorption geometry. Performed investigations confirm the original thermodynamic approach to creation of thermally stable multi-layer materials.
相似文献998.
Ivan Hlaváček 《Applications of Mathematics》2007,52(3):187-196
An introduction to the worst scenario method is given. We start with an example and a general abstract scheme. An analysis
of the method both on the continuous and approximate levels is discussed. We show a possible incorporation of the method into
the fuzzy set theory. Finally, we present a survey of applications published during the last decade.
This work was supported by grant 201/04/1503 from the Czech Science Foundation and by the Academy of Sciences of the Czech
Republic, Institutional Research Plan No. AV0Z10190503 相似文献
999.
M. Elkurdi P. Boucaud S. Sauvage G. Fishman O. Kermarrec Y. Campidelli D. Bensahel G. Saint-Girons G. Patriarche I. Sagnes 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):450
We have investigated the interband and the intraband absorption properties of Ge/Si self-assembled islands. The investigated structure consists of a p–i–n junction containing Ge/Si self-assembled islands embedded in a Si0.98Ge0.02 waveguiding layer. The variation of transmission associated with carrier injection under forward bias is monitored both in the near-infrared and in the mid-infrared spectral ranges. We show that the carrier injection leads to an absorption resonant at 185 meV which is polarized along the growth axis of the islands. This transition corresponds to an intraband optical transition from the island ground states to the two-dimensional wetting layer states. This assignment is supported by a two-dimensional band structure calculation performed in a 14 band k·p formalism. Meanwhile, the carrier injection leads to a bleaching of the interband absorption. We show that this electroabsorption spectroscopy is a useful tool for the study of self-assembled islands that is complementary of standard photoluminescence, electroluminescence or absorption spectroscopies. 相似文献
1000.
We present an efficient self-consistent method for approaching quantum transport through atomic-scale structures. Using the recursion-transfer-matrix (RTM) method with a separable form of nonlocal pseudopotentials, scattering waves propagating between metallic electrodes through nano-bridged structures are efficiently calculated on the basis of the density-functional formalism. We performed calculations with this method of the conductance of Al atomic wires with various kinds of single atoms mixed at the contact to one electrode. We found that the transport properties are considerably affected by the bonding nature of the atom at the contact. The conductance is largely determined by the atomic species at the contact and does not change much as the length of the atomic wire increases. 相似文献