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1.
Understanding and control of the surface properties such as molecular orientations are of great importance in numerous applications of ionic liquids. However, there remain discrepancies among the previous experimental and theoretical studies on the surface orientation and structures of room temperature ionic liquids(RTIL) systems. In this article, the orientation of 1-butyl-3-methylimidazolium([bmin]) cation at the air/liquid interface of a characteristic RTIL, 1-butyl-3-methylimidazolium hexafluorophosphate([bmim][PF6]), was investigated by the sum frequency generation vibrational spectroscopy(SFG-VS). Detailed polarization and experimental configuration analyses of the SFG-VS spectra showed the possibility of a small spectral splitting in the CH3 symmetric stretching region, which can be further attributed to the probable existence of multiple orientations for the interfacial [bmim] cations. In addition, the(N)–CH3 vibrations were absent, ruling out the prediction by several recent molecular dynamics simulations which state that portions of the [bmim] cations orient with a standing-up(N)–CH3 group at the ionic liquid surface. Hence, new realistic theoretical models have to be developed to reflect the complex nature of the ionic liquid surface. 相似文献
2.
Antoine Letessier-Selvon for the Pierre Auger Collaboration 《Brazilian Journal of Physics》2014,44(5):560-570
The Pierre Auger Observatory is the world’s largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km 2sr and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these, we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our X max data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass-sensitive parameters from the 100 % duty cycle surface detector (SD) data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of ultrahigh-energy cosmic ray (UHECR) sources are briefly discussed. 相似文献
3.
I. Paradela Pérez M. Groth M. Wischmeier D. Coster D. Brida P. David D. Silvagni M. Faitsch the ASDEX-Upgrade Team the EUROfusion MST Team 《等离子体物理论文集》2020,60(5-6):e201900166
SOLPS-ITER L-mode-like simulations with the full set of currents and drift velocities activated, and fluid neutrals have been carried out to interpret experimental results obtained in AUG. Drifts are critical to quantitatively reproduce the experimental results; however, simulations without drifts can also reproduce some trends qualitatively. The magnitude and dependence of the peak heat flux onto both targets on the upstream collisionality are, in general, in quantitative agreement within uncertainties with infrared thermography measurements in favourable field direction. The onset of power detachment is observed. In unfavourable toroidal field direction, a more symmetrical inner/outer target solution with regards to the power distribution is predicted, in agreement with experimental observations. However, also in unfavourable toroidal field direction, insufficient power is dissipated in the simulations and therefore qpeak, inn is overpredicted by up to a factor of 4 and qpeak, out by up to a factor of 1.5. The largest contribution to the sources due to radial transport in the energy balance equation is the radial divergence of the energy flux due to VE × B. 相似文献
4.
5.
Li Caldeira Balkeståhl Erik Thomé on behalf of the PANDA Collaboration 《Hyperfine Interactions》2014,229(1-3):79-83
Strangeness and charm production provide an excellent probe of QCD in the confinement domain. With the PANDA detector at FAIR, this can be studied in e.g., hyperon production in the p?p → ?Y reactions. In PANDA, all ground state strange hyperons and single charmed Λ’s will be accessible. Simulations show that the differential cross sections and spin observables can be well reconstructed for these reaction channels. 相似文献
6.
7.
Abstract Pair defects consisting of F centres and CN? molecules as substitutional impurity anions (FH(CN?) centres) exhibit a strong coupling between the F centres and the CN? molecules. This leads to an optical pumping of the CN? vibrations via the F centre absorption band. We performed an Electron Nuclear Double Resonance (ENDOR) investigation in order to analyse the microscopic structure of these aggregate centres. The CN? molecule occupies a [110] nearest anion position with respect to the F centre in two dynamic dipole orientations even at low temperature. 相似文献
8.
HAN Tao LU XiaoChun WANG Xue RAO YongNan ZOU DeCai YANG JianFei & WU YangYang National Time Service Center Xi'an China Key Laboratory of Precision Navigation Timing Technology Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS tha... 相似文献
9.
A. Mokhles Gerami K. Johnston H. P. Gunnlaugsson K. Nomura R. Mantovan H. Masenda Y. A. Matveyev T. E. Mølholt M. Ncube S. Shayestehaminzadeh I. Unzueta H. P. Gislason P. B. Krastev G. Langouche D. Naidoo S. Ólafsson the ISOLDE collaboration 《Hyperfine Interactions》2016,237(1):75
Emission Mössbauer spectroscopy has been utilised to characterize dilute 57Fe impurities in In 2O3 following implantation of 57Mn (T 1/2 = 1.5 min.) at the ISOLDE facility at CERN. From stoichiometry considerations, one would expect Fe to adopt the valence state 3 + , substituting In 3+, however the spectra are dominated by spectral lines due to paramagnetic Fe2+. Using first principle calculations in the framework of density functional theory (DFT), the density of states of dilute Fe and the hyperfine parameters have been determined. The hybridization between the 3d-band of Fe and the 2p band of oxygen induces a spin-polarized hole on the O site close to the Fe site, which is found to be the cause of the Fe2+ state in In 2O3. Comparison of experimental data to calculated hyperfine parameters suggests that Fe predominantly enters the 8b site rather than the 24d site of the cation site in the Bixbyite structure of In 2O3. A gradual transition from an amorphous to a crystalline state is observed with increasing implantation/annealing temperature. 相似文献
10.
Abstract ENDOR investigations show that in nearly stoichiometric LiNbO3 Mn2+ substitutes for Li with a Li vacancy in the first Li shell for most centres. In heavily Mg codoped LiNbO3 the Cr3+ dopant, characterized by a new isotropic ESR signal, is shown to substitute for Nb. Information on local disorder is obtained. 相似文献