全文获取类型
收费全文 | 26328篇 |
免费 | 2065篇 |
国内免费 | 1575篇 |
专业分类
化学 | 1143篇 |
晶体学 | 65篇 |
力学 | 4162篇 |
综合类 | 334篇 |
数学 | 20762篇 |
物理学 | 3502篇 |
出版年
2024年 | 43篇 |
2023年 | 269篇 |
2022年 | 370篇 |
2021年 | 429篇 |
2020年 | 616篇 |
2019年 | 643篇 |
2018年 | 653篇 |
2017年 | 717篇 |
2016年 | 785篇 |
2015年 | 584篇 |
2014年 | 1165篇 |
2013年 | 2126篇 |
2012年 | 1157篇 |
2011年 | 1418篇 |
2010年 | 1238篇 |
2009年 | 1656篇 |
2008年 | 1744篇 |
2007年 | 1735篇 |
2006年 | 1534篇 |
2005年 | 1258篇 |
2004年 | 1162篇 |
2003年 | 1121篇 |
2002年 | 1034篇 |
2001年 | 826篇 |
2000年 | 805篇 |
1999年 | 702篇 |
1998年 | 688篇 |
1997年 | 597篇 |
1996年 | 464篇 |
1995年 | 355篇 |
1994年 | 297篇 |
1993年 | 254篇 |
1992年 | 231篇 |
1991年 | 212篇 |
1990年 | 170篇 |
1989年 | 96篇 |
1988年 | 84篇 |
1987年 | 77篇 |
1986年 | 74篇 |
1985年 | 100篇 |
1984年 | 109篇 |
1983年 | 64篇 |
1982年 | 73篇 |
1981年 | 52篇 |
1980年 | 43篇 |
1979年 | 36篇 |
1978年 | 31篇 |
1977年 | 18篇 |
1976年 | 14篇 |
1973年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
We treat here of the question of absorbing boundary conditionsfor nonlinear diffusion equations. We use the conditions designedfor the linear equation, we prove them to be well posed forthe nonlinear problem, and through numerical experiments thatthey are well suited for reactiondiffusion equations. 相似文献
32.
A one-dimensional bulk reaction model for the oxidation of nickeltitanium is formulated, with preferential oxidation of titaniumbeing included. The modelling is directed at the better understandingof the dominant mechanisms involved in the oxidation processand their significance for the biocompatibility of the alloy.Two different regimes for the relative diffusivities of oxygenand the metals are investigated. By assuming fast bulk reactions,different asymptotic structures emerge in different parameterregimes and the resulting models take the form of moving boundaryproblems. Different profiles of nickel concentration are obtained:in particular a nickel-rich layer (observed in practice) ispresent below the oxide/metal interface for the case when oxygenand the metals diffuse at comparable rates. 相似文献
33.
I. P. Kayumov 《Mathematical Notes》2005,78(3-4):498-502
In this paper, we prove Brennan's conjecture for conformal mappings f of the disk {z : | z| < 1} assuming that the Taylor coefficients of the function log(zf′(z)/f(z)) at zero are nonnegative. We also obtain inequalities for the integral means over the circle |z| = r of the squared modulus of the function zf′(z)/f(z). 相似文献
34.
Guy Bayada 《Journal of Mathematical Analysis and Applications》2003,282(1):212-231
The asymptotic behaviour of a Stokes flow with Tresca free boundary friction conditions when one dimension of the fluid domain tends to zero is studied. A specific Reynolds equation associated with variational inequalities is obtained and uniqueness is proved. 相似文献
35.
36.
Tiegang Fang 《International Journal of Non》2008,43(9):1007-1011
The unsteady boundary layer over a semi-infinite flat plate was investigated in this paper. The flow involves the unsteady flow over a flat plate with leading edge accretion or ablation. The momentum boundary layer was further analyzed and it was shown that the leading edge ablation had a similar effect to the wall mass injection or upstream wall movement making the fluid blown away from the wall. The thermal boundary layer of the same flow was also studied. Results show that the leading edge accretion or ablation can greatly change the fluid motion and the heat transfer characteristics. 相似文献
37.
38.
一类含有P-Laplacian算子的奇异边值问题解的确切个数 总被引:2,自引:0,他引:2
讨论了一类p-L ap lac ian算子型的奇异边值问题正解的确切个数以及解的性质. 相似文献
39.
The numerical prediction of the fields of inelastic strains (the linear invariant of the tensor of inelastic strains) in thermoset polyester/marble filler composite plates is discussed. A uniformly distributed load is applied to the plates, which lie on a steel base. The strain fields are predicted by means of the boundary element method by using creep test data for the composites and the polyester matrix itself. Identical creep tests were performed for two ages of the materials (1 month and 13 years), which allowed evaluating the aging effect. The study is carried out in two stages. At the first stage, the application of the generalized Maxwell-Gurevich equation to the thermoset matrix/mineral filler composite is demonstrated. The model parameters determined from the experimental creep data is used for the second stage, where the state of inelastic strains in the plates is predicted by applying the boundary element method. The influence of composite formulation (filler content) and physical aging of the polyester matrix on the state of inelastic strains in the plates is shown.__________Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 41, No. 2, pp. 145–156, March–April, 2005. 相似文献
40.
ZhenFengZHANG 《数学学报(英文版)》2005,21(1):155-168
In this paper, we extend a classical result of Hua to arithmetic progressions with large moduli. The result implies the Linnik Theorem on the least prime in an arithmetic progression. 相似文献