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991.
N. G. Moshchevitin 《Mathematical Notes》1998,64(2):194-201
Recurrence of an individual trajectory of a linear nonautonomous differential equation on a compact Lie group for the case of an almost periodic or conditionally periodic dependence of the right-hand side on time is proved. The relation between recurrence and reducibility is examined.Translated fromMatematicheskie Zametki, Vol. 64, No. 2, pp. 229–237, August, 1998.This research was supported by the Russian Foundation for Basic Research under grants No. 96-01-00378 and No. 96-15-96072. 相似文献
992.
Jin Yun GUO Bing Jun LI Qiu Xian WU 《数学学报(英文版)》2006,22(3):849-854
In this paper, we prove that there is a natural equivalence between the category F1(x) of Koszul modules of complexity 1 with filtration of given cyclic modules as the factor modules of an exterior algebra A = ∧V of an m-dimensional vector space, and the category of the finite-dimensional locally nilpotent modules of the polynomial algebra of m - 1 variables. 相似文献
993.
设Aq=k/(x2,xy+qyx,y2)是含有两个变量的广义外代数,基于Buch- weitz等人构造的极小投射双模解,广义外代数的各阶Hochschild同调群的维数被清晰地计算. 相似文献
994.
V. V. Redkozubov 《Mathematical Notes》2006,79(5-6):681-686
A trick which reduces some questions concerning the dynamics of self-maps of the circle to similar questions about self-maps of the interval is suggested and applied to answer two questions of Block and Coppel. 相似文献
995.
进一步讨论了带有对称编码的基因算法中采用的部分基因保留技术对算法性能的影响,确定了最佳基因保留量(25%)及其选择范围(20%~50%),对算法的计算机实验所得到的结果表明,如果不采用这项技术,带有对称编码的基因算法的性能就会降低,所得到的解的质量就会下降。 相似文献
996.
997.
F. Alouges J. Laminie S. M. Mefire 《Numerical Methods for Partial Differential Equations》2003,19(5):595-637
We describe the simulation of an exterior problem using a magnetic field deriving from magnetostatics, with a numerical method mixing the approaches of C. I. Goldstein and L.‐A. Ying. This method is based on the use of a graded mesh obtained by gluing homothetic layers in the exterior domain. On this mesh, we use an edge elements discretization and a recently proposed mixed formulation. In this paper, we provide both a theoretical and numerical study of the method. We establish an error estimate, describe the implementation, propose some preconditioning techniques and show the numerical results. We also compare these results with those obtained from an equivalent boundary elements approach. In this way, we retain that our method leads to a practical numerical implementation, a saving of storage, and turns out to be an alternative to the classical boundary elements method. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 595–637, 2003 相似文献
998.
999.
Dan Li Yuliang Wang Jun Wang Yingtao Zhao 《International journal of quantum chemistry》2013,113(21):2379-2384
We present a detailed quasiclassical trajectory (QCT) study of the dynamics corresponding to the reaction H + LiH proceeding via depletion and H‐exchange paths on a new potential energy surface of the electronic ground state. The effects of collision energy and reagent initial vibrational excitation on the reaction probability and cross sections are studied over a wide range of collision energies. The QCT‐calculated reaction probability and cross sections are in good agreement with previous time‐dependent wave packet results. More importantly, we found that the vibrational excitation of LiH molecule inhibits the LiH depletion reaction, whereas it promotes the H‐exchange reaction. In addition, the differential cross sections calculated for the depletion reaction at different collision energies and excitation states indicate a strong forward scattering of the product molecule H2. © 2013 Wiley Periodicals, Inc. 相似文献
1000.
Within three functionals (TD-B3LYP, TD-BHandHLYP, and TD-CAM-B3LYP) in combination with four basis sets (3-21g, 6-31g, 6-31g(d), and cc-pvdz), global switching (GS) trajectory surface hopping molecular dynamics has been performed for cis-to-trans azobenzene photoisomerization up to the S1(nπ*) excitation. Although all the combinations show artificial double-cone structure of conical intersection between ground and first excited states, simulated quantum yields and lifetimes are in good agreement with one another; 0.6 (±5%) and 40.5 fs (±10%) by TD-B3LYP, 0.5 (±10%) and 35.5 fs (±4%) by TD-BHandHLYP, and 0.44 (±9%) and 35.2 fs (±10%) by TD-CAM-B3LYP. By analyzing distributions of excited-state population decays, hopping spots, and typical trajectories with performance of 12 functional/basis set combinations, it has been concluded that functional dependence for given basis set is slightly more sensitive than basis set dependence for given functional. The present GS on-the-fly time-dependent density functional theory (TDDFT) trajectory surface hopping simulation can provide practical benchmark guidelines for conical intersection driven excited-state molecular dynamics simulation involving in large complex system within ordinary TDDFT framework. © 2019 Wiley Periodicals, Inc. 相似文献