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991.
The collective properties in the even-even 78-84Kr isotopes have been studied within the framework of the SD-pair shell model.It is found that the collectivity of low-lying states in the even-even Kr isotopes can be described very well. 相似文献
992.
An investigation of the optical properties of a hydrogenic donor in spherical parabolic quantum dots has been performed by using the matrix diagonalization method. The optical absorption coefficient between the ground (L = 0) and the first excited state (L = 1) have been examined based on the computed energies and wave functions. The results are presented as a function of the incident photon energy for the different values of the confinement strength. These results show the effects of the quantum size and the impurity on the optical absorption coefficient of a donor impurity quantum dot. 相似文献
993.
We developed a constituent quark-diquark model for the nucleon and its resonances using a harmonic oscillator potential for
the interaction. The effects due to relativistic kinetic energy correction are studied. Finally, charge form factor of the
model is calculated and compared with experimental data.
相似文献
994.
Béchir Rezgui Abel Sibai Tetyana Nychyporuk Mustapha Lemiti Georges Brémond 《Journal of luminescence》2009,129(12):1744-582
Silicon nitride (SiNx) films were prepared with a gas mixture of SiH4 and NH3 on Si wafers using the plasma-enhanced chemical vapor deposition (PECVD) method. High-resolution transmission electron microscopy and infrared absorption have been used to reveal the existence of the Si quantum dots (Si QDs) and to determine the chemical composition of the silicon nitride layers. The optical properties of these structures were studied by photoluminescence (PL) spectroscopy and indicate that emission mechanisms are dominated by confined excitons within Si QDs. The peak position of PL could be controlled in the wavelength range from 1.5 to 2.2 eV by adjusting the flow rates of ammonia and silane gases. Absorbance spectra obtained in the transmission mode reveal optical absorption from Si QDs, which is in good correlation with PL properties. These results have implications for future nanomaterial deposition controlling and device applications. 相似文献
995.
A chaotic attractor is usually characterised by its multifractal spectrum which gives a geometric measure of its complexity. Here we present a characterisation using a minimal set of independent parameters which is uniquely determined by the underlying process that generates the attractor. The method maps the f(α) spectrum of a chaotic attractor on to that of a general two scale Cantor measure. We show that the mapping can be done in practice with reasonable accuracy for many of the standard chaotic attractors. In order to implement this procedure, we also propose a generalisation of the standard equations for the two scale Cantor set in one dimension to that in higher dimensions. Another interesting result we have obtained both theoretically and numerically is that, the f(α) characterisation gives information only up to two scales, even when the underlying process generating the multifractal involves more than two scales. 相似文献
996.
997.
Laurence S. Rothman 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(11):1514-1515
The publication by G.H. Dieke and H.M. Crosswhite (JQSRT 1962;2:97-199) is a classic paper detailing the spectroscopy of the A2Σ+←X2Π bands of the hydroxyl radical (OH) in the ultraviolet region. It soon became the basis of astrophysical modeling, most subsequent theoretical and laboratory studies of the OH individual line parameters, and a host of other applications. 相似文献
998.
Inside Cover: Enhancement of Light Absorption Ability of Synthetic Chlorophyll Derivatives by Conjugation with a Difluoroboron Diketonate Group (Chem. Eur. J. 29/2016) 下载免费PDF全文
999.
1000.
Y. Benmimoun A. Bouhemadou R. Khenata A. H. Reshak B. Amrani M. Ameri H. Baltache 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(2):165-171
The results of first-principles theoretical study of the structural,
electronic and optical properties of SrCl2 in its cubic structure, have
been performed using the full-potential linear augmented plane-wave method
plus local orbitals (FP-APW+lo) as implemented in the WIEN2k code. In this
approach both the local density approximation (LDA) and the generalized
gradient approximation (GGA) are used for the exchange-correlation (XC)
potential. Also we have used the Engel-Vosko GGA formalism, which optimizes
the corresponding potential for band structure calculations. We performed
these calculations with and without spin-orbit interactions. Including
spin-orbit coupling cause to lifts the triple degeneracy at Γ point
and a double degeneracy at X point. Results are given for structural
properties. The pressure dependence of elastic constants and band gaps are
investigated. The dielectric function, reflectivity spectra and refractive
index are calculated up to 30 eV. Also we calculated the pressure and volume
dependence of the static optical dielectric constant. 相似文献