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991.
992.
A path-integral Monte Carlo algorithm for the simulation of electrons solvated in polar liquids is briefly outlined, and results
are presented for the electron solvated in liquid water. 相似文献
993.
Michal Korenko Marián Kucharík Jozef Vincenc Oboňa Dušan Janičkovič Rosa Córdoba José María De Teresa Blanka Kubíková 《Helvetica chimica acta》2008,91(7):1389-1399
The rapid‐solidification processing (by a cooling rate of 105–106 K/s) was used for the preparation of deeply undercooled cryolite/alumina (Na3AlF6/Al2O3) melts. We found a mass of nanotubes on the surface of these undercooled melts. The nanotubes were preferentially located on the defect places of the surface with the following approximate dimensions: base≈100×100 nm, length≈1000 nm. The solidified samples with the nanotubes on the surface were analyzed by scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD), and infrared spectroscopy (IR). 相似文献
994.
V. Vescoli F. Zwick W. Henderson L. Degiorgi M. Grioni G. Gruner L.K. Montgomery 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,13(3):503-511
Combined optical and photoemission experiments on the quasi-one dimensional Bechgaard salts reveal the non-Fermi liquid character
of these prototype quasi-one dimensional interacting electron systems. We show that various aspects of the exotic normal state
properties along the chains are consistent with the predictions of the Tomonaga-Luttinger liquid theory. We also discuss the
effect of interchain coupling on the insulator-metal transition, associated with the electron confinement-deconfinement crossover.
Received 17 May 1999 and Received in final form 13 July 1999 相似文献
995.
Mei Zhong JIN Li YANG Long Ming WU You Chen LIU Zhong Li LIU* National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2001,(4)
Reduction of C=N double bonds has been recognized as an important reaction both in organic chemistry and bio-chemistry1. Hantzsch 1,4-dihydropyridine (HEH, one of NADH model compounds) has been reported as a reductive reagent for imines2. However, application of dihydropyridines as practical reducing reagents in organic synthesis is limited because of their instability3. Like NADH models, 2-phenyl-N, N-dimethylbenzimidazoline (PDMBI) is an efficient electron and hydrogen donor (Eox = 0… 相似文献
996.
I. A. Akimov V. F. Sapega D. N. Mirlin V. M. Ustinov 《Physica E: Low-dimensional Systems and Nanostructures》2001,10(4):129
We have studied the dependence of hot electron scattering rate on temperature in n-GaAs/AlAs types I and II multiple quantum wells. For a sample with well width 37 Å, which is on the borderline between types I and II band alignment, the increase of the temperature in the range 6–80 K leads to the strong decrease of the hot electron scattering rate. We explain this result by ionization of donors and transfer of cold electrons from the Γ-valley of GaAs to the X-valley of AlAs. 相似文献
997.
Minghui Song Kazutaka Mitsuishi Kazuo Furuya 《Physica E: Low-dimensional Systems and Nanostructures》2005,29(3-4):575
Nanometer-sized W-dendrites are fabricated on Al2O3 substrates with an electron-beam-induced deposition process. Dependence of growth of nanodendrite on surface topography is investigated with transmission electron microscopy. It is confirmed that the nanodendrite grows on convex surfaces but not around a hole on a substrate. These are attributed to different distribution of charges on surfaces with different topographies during electron beam irradiation when charges are produced on the surface due to emission of second electrons. The charges accumulate on convex surface and do not distribute around a hole. Therefore, the nanodendrite grows on the former and not on the latter. 相似文献
998.
Chenghe Xu Lezhu Zhou Anshi Xu 《International Journal of Infrared and Millimeter Waves》1989,10(1):55-62
The analytic theory of microwave open resonators is improved here by means of solving the complex Airy equation, that the Q-value as well as the argument of field profile may be given accurately. The resonance conditions for open cavities with high and moderate Q-values are derived analytically. Theoreticl Q-values are well agreed with the measured ones from experiments. 相似文献
999.
1000.
A. Surzhykov U. D. Jentschura T. Stöhlker S. Fritzsche 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(1):27-36
We apply the density matrix theory to re-investigate the radiative
electron capture into heavy ions with one valence electron. Attention
has been paid particularly to the magnetic sublevel population of the
residual ions, as described in terms of alignment parameters. Simple
method, based on an independent particle model, which takes
into account the Pauli principle, is proposed for evaluating the
alignment of the excited ionic states. By making use of this method,
detailed calculations are performed for electron capture into (initially) hydrogen-like and lithium-like europium, gold and
uranium ions, and are compared with the results of the multiconfiguration Dirac-Fock approach.As seen from the calculations
and from the comparison with available experimental results, the independent particle model provides a good estimate for the
alignment parameters of few-electron heavy ions. Therefore, our simple model may help to understand the basic properties of
the X-ray emission from heavy, few-electron ions without the need for invoking sophisticated MCDF calculations. 相似文献