全文获取类型
收费全文 | 1626篇 |
免费 | 108篇 |
国内免费 | 97篇 |
专业分类
化学 | 21篇 |
晶体学 | 2篇 |
力学 | 367篇 |
综合类 | 19篇 |
数学 | 1155篇 |
物理学 | 267篇 |
出版年
2024年 | 6篇 |
2023年 | 28篇 |
2022年 | 23篇 |
2021年 | 23篇 |
2020年 | 40篇 |
2019年 | 43篇 |
2018年 | 54篇 |
2017年 | 50篇 |
2016年 | 63篇 |
2015年 | 53篇 |
2014年 | 82篇 |
2013年 | 169篇 |
2012年 | 43篇 |
2011年 | 102篇 |
2010年 | 70篇 |
2009年 | 95篇 |
2008年 | 94篇 |
2007年 | 89篇 |
2006年 | 72篇 |
2005年 | 80篇 |
2004年 | 56篇 |
2003年 | 67篇 |
2002年 | 50篇 |
2001年 | 54篇 |
2000年 | 61篇 |
1999年 | 47篇 |
1998年 | 43篇 |
1997年 | 32篇 |
1996年 | 23篇 |
1995年 | 18篇 |
1994年 | 20篇 |
1993年 | 9篇 |
1992年 | 5篇 |
1991年 | 11篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 10篇 |
1987年 | 8篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1980年 | 1篇 |
1979年 | 2篇 |
排序方式: 共有1831条查询结果,搜索用时 31 毫秒
111.
吴昭君 《数学物理学报(B辑英文版)》2014,(2):380-386
The author proves that if f : C→Cn is a transcendental vector valued meromorphic function of finite order and assume Σa∈Cn ∪{∞}δ(a) = 2, then,where .This result extends the related results for meromorphic function by Singh and Kulkarni. 相似文献
112.
We investigate the global existence and asymptotic behavior of classical solutions for the 3D compressible non-isentropic damped Euler equations on a periodic domain. The global existence and uniqueness of classical solutions are obtained when the initial data is near an equilibrium. Furthermore, the exponential convergence rates of the pressure and velocity are also proved by delicate energy methods. 相似文献
113.
114.
We prove an omega estimate related to the general Euler totient function associated to a polynomial Euler product satisfying some natural analytic properties. For convenience, we work with a set of L-functions similar to the Selberg class, but in principle our results can be proved in a still more general setup. In a recent paper the authors treated a special case of Dirichlet L-functions with real characters. Greater generality of the present paper invites new technical difficulties. Effectiveness of the main theorem is illustrated by corollaries concerning Euler totient functions associated to the shifted Riemann zeta function, shifted Dirichlet L-functions and shifted L-functions of modular forms. Results are either of the same quality as the best known estimates or are entirely new. 相似文献
115.
A generalized Nevanlinna function Q(z) with one negative square has precisely one generalized zero of nonpositive type in the closed extended upper halfplane. The fractional linear transformation defined by Qτ(z)=(Q(z)−τ)/(1+τQ(z)), τ∈R∪{∞}, is a generalized Nevanlinna function with one negative square. Its generalized zero of nonpositive type α(τ) as a function of τ is being studied. In particular, it is shown that it is continuous and its behavior in the points where the function extends through the real line is investigated. 相似文献
116.
117.
The phenomena of concentration and cavitation and the formation of δ-shocks and vacuum states in solutions to the isentropic Euler equations for a modified Chaplygin gas are analyzed as the double parameter pressure vanishes. Firstly, the Riemann problem of the isentropic Euler equations for a modified Chaplygin gas is solved analytically. Secondly, it is rigorously shown that, as the pressure vanishes, any two-shock Riemann solution to the isentropic Euler equations for a modified Chaplygin gas tends to a δ-shock solution to the transport equations, and the intermediate density between the two shocks tends to a weighted δ-measure that forms the δ-shock; any two-rarefaction-wave Riemann solution to the isentropic Euler equations for a modified Chaplygin gas tends to a two-contact-discontinuity solution to the transport equations, the nonvacuum intermediate state between the two rarefaction waves tends to a vacuum state. Finally, some numerical results exhibiting the formation of δ-shocks and vacuum states are presented as the pressure decreases. 相似文献
118.
Some results are presented on the formation of singularities in the solutions of the radially-symmetric N-dimensional Euler or Euler–Poisson equations with repulsive forces. Based on the integration method of M.W. Yuen, we generalize the blowup results with constant compact radius R of solutions to the case with general compact radius R(t) and to the case with no compact support restriction. 相似文献
119.
利用直接的方法讨论了在自相似平面上气体动力学中二维压差方程的特征分解理论,得到了压强P和特征值A±的特征分解.进一步地,若流动来自常状态,还可得到速度(u,v)的特征分解.由此,可以得到与常状态流动相邻的流动是简单波,并说明了简单波的流动区域是被一族直线所覆盖,且沿着每条直线, (P,u,v)为常数. 相似文献
120.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(7):2172-2180
This paper presents the vortical and self-similar solutions for 2D compressible Euler equations using the separation method. These solutions complement Makino’s solutions in radial symmetry without rotation. The rotational solutions provide new information that furthers our understanding of ocean vortices and reference examples for numerical methods. In addition, the corresponding blowup, time-periodic or global existence conditions are classified through an analysis of the new Emden equation. A conjecture regarding rotational solutions in 3D is also made. 相似文献