全文获取类型
收费全文 | 18146篇 |
免费 | 671篇 |
国内免费 | 506篇 |
专业分类
化学 | 3440篇 |
晶体学 | 123篇 |
力学 | 640篇 |
综合类 | 68篇 |
数学 | 9926篇 |
物理学 | 5126篇 |
出版年
2024年 | 30篇 |
2023年 | 171篇 |
2022年 | 258篇 |
2021年 | 259篇 |
2020年 | 400篇 |
2019年 | 469篇 |
2018年 | 452篇 |
2017年 | 355篇 |
2016年 | 341篇 |
2015年 | 377篇 |
2014年 | 718篇 |
2013年 | 990篇 |
2012年 | 526篇 |
2011年 | 1501篇 |
2010年 | 1068篇 |
2009年 | 1268篇 |
2008年 | 1412篇 |
2007年 | 1283篇 |
2006年 | 1005篇 |
2005年 | 821篇 |
2004年 | 694篇 |
2003年 | 597篇 |
2002年 | 571篇 |
2001年 | 315篇 |
2000年 | 342篇 |
1999年 | 358篇 |
1998年 | 278篇 |
1997年 | 258篇 |
1996年 | 267篇 |
1995年 | 241篇 |
1994年 | 250篇 |
1993年 | 216篇 |
1992年 | 178篇 |
1991年 | 120篇 |
1990年 | 101篇 |
1989年 | 106篇 |
1988年 | 66篇 |
1987年 | 66篇 |
1986年 | 65篇 |
1985年 | 90篇 |
1984年 | 83篇 |
1983年 | 44篇 |
1982年 | 75篇 |
1981年 | 54篇 |
1980年 | 49篇 |
1979年 | 26篇 |
1978年 | 38篇 |
1977年 | 29篇 |
1976年 | 21篇 |
1974年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
B. Amaziane M. Goncharenko L. Pankratov 《Mathematical Methods in the Applied Sciences》2005,28(15):1847-1865
We study the asymptotic behaviour of the solution of a stationary quasilinear elliptic problem posed in a domain Ω(ε) of asymptotically degenerating measure, i.e. meas Ω(ε) → 0 as ε → 0, where ε is the parameter that characterizes the scale of the microstructure. We obtain the convergence of the solution and the homogenized model of the problem is constructed using the notion of convergence in domains of degenerating measure. Proofs are given using the method of local characteristics of the medium Ω(ε) associated with our problem in a variational form. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
22.
23.
24.
Summary In this paper, we develop a framework suitable for performing a multiresolution analysis using univariate spline spaces of arbitrary degree and with non-uniform knot-sequences. To this end, we show, among other things, the existence of compactly supported prewavelets and of prewavelets that are globally supported, but decay exponentially. In each case we obtain a decomposition of a fine spline space as a sum of a coarse spline space plus a spline space spanned by prewavelets. 相似文献
25.
26.
In this paper we generalize to coisotropic actions of compact Lie groups a theorem of Guillemin on deformations of Hamiltonian
structures on compact symplectic manifolds. We show how one can reconstruct from the moment polytope the symplectic form on
the manifold.
Received: 21 March 2006 相似文献
27.
We construct cellular homotopy theories for categories of simplicial presheaves on small Grothendieck sites and discuss applications to the motivic homotopy category of Morel and Voevodsky. 相似文献
28.
The main results of the paper are as follows: covering characterizations of wQN-spaces, covering characterizations of QN-spaces and a theorem saying that Cp(X) has the Arkhangel'ski?ˇ property (α1) provided that X is a QN-space. The latter statement solves a problem posed by M. Scheepers [M. Scheepers, Cp(X) and Arhangel'ski?ˇ's αi-spaces, Topology Appl. 89 (1998) 265-275] and for Tychonoff spaces was independently proved by M. Sakai [M. Sakai, The sequence selection properties of Cp(X), Preprint, April 25, 2006]. As the most interesting result we consider the equivalence that a normal topological space X is a wQN-space if and only if X has the property S1(Γshr,Γ). Moreover we show that X is a QN-space if and only if Cp(X) has the property (α0), and for perfectly normal spaces, if and only if X has the covering property (β3). 相似文献
29.
Valery Agoshkov Paola Gervasio Alfio Quarteroni 《Mediterranean Journal of Mathematics》2006,3(2):147-176
New domain decomposition methods (DDM) based on optimal control approach are introduced for the coupling of first and second
order equations on overlapping subdomains. Several cost functionals and control functions are proposed. Uniqueness and existence
results are proved for the coupled problem, and the convergence of iterative processes is analyzed.
The work was supported by the Russian Foundation for Basic Research (04-01-00615) and it was partly carried out while the
first author was visiting the IACS at EPFL. 相似文献
30.
Igor Chueshov 《Journal of Differential Equations》2007,233(1):42-86
We study von Karman evolution equations with non-linear dissipation and with partially clamped and partially free boundary conditions. Two distinctive mechanisms of dissipation are considered: (i) internal dissipation generated by non-linear operator, and (ii) boundary dissipation generated by shear forces friction acting on a free part of the boundary. The main emphasis is given to the effects of boundary dissipation. Under suitable hypotheses we prove existence of a compact global attractor and finiteness of its fractal dimension. We also show that any solution is stabilized to an equilibrium and estimate the rate of the convergence which, in turn, depends on the behaviour at the origin of the functions describing the dissipation. 相似文献