全文获取类型
收费全文 | 2026篇 |
免费 | 93篇 |
国内免费 | 5篇 |
专业分类
化学 | 1347篇 |
晶体学 | 1篇 |
力学 | 28篇 |
数学 | 448篇 |
物理学 | 300篇 |
出版年
2023年 | 12篇 |
2022年 | 16篇 |
2021年 | 33篇 |
2020年 | 36篇 |
2019年 | 50篇 |
2018年 | 26篇 |
2017年 | 18篇 |
2016年 | 63篇 |
2015年 | 62篇 |
2014年 | 58篇 |
2013年 | 65篇 |
2012年 | 121篇 |
2011年 | 154篇 |
2010年 | 72篇 |
2009年 | 60篇 |
2008年 | 85篇 |
2007年 | 88篇 |
2006年 | 111篇 |
2005年 | 102篇 |
2004年 | 70篇 |
2003年 | 72篇 |
2002年 | 62篇 |
2001年 | 49篇 |
2000年 | 52篇 |
1999年 | 44篇 |
1998年 | 46篇 |
1997年 | 35篇 |
1996年 | 38篇 |
1995年 | 32篇 |
1994年 | 41篇 |
1993年 | 28篇 |
1992年 | 45篇 |
1991年 | 37篇 |
1990年 | 23篇 |
1989年 | 16篇 |
1988年 | 16篇 |
1987年 | 10篇 |
1986年 | 9篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 17篇 |
1982年 | 8篇 |
1981年 | 12篇 |
1979年 | 8篇 |
1977年 | 7篇 |
1976年 | 8篇 |
1974年 | 8篇 |
1973年 | 9篇 |
1971年 | 7篇 |
1968年 | 8篇 |
排序方式: 共有2124条查询结果,搜索用时 31 毫秒
1.
Cui Shisheng Shanbhag Uday Staudigl Mathias Vuong Phan 《Computational Optimization and Applications》2022,82(2):465-498
Computational Optimization and Applications - We develop a globalized Proximal Newton method for composite and possibly non-convex minimization problems in Hilbert spaces. Additionally, we impose... 相似文献
2.
3.
We consider normal ≡ Gaussian seemingly unrelated regressions (SUR) with incomplete data (ID). Imposing a natural minimal set of conditional independence constraints, we find a restricted SUR/ID model whose likelihood function and parameter space factor into the product of the likelihood functions and the parameter spaces of standard complete data multivariate analysis of variance models. Hence, the restricted model has a unimodal likelihood and permits explicit likelihood inference. In the development of our methodology, we review and extend existing results for complete data SUR models and the multivariate ID problem. 相似文献
4.
C. Brunhuber F. G. Mertens Y. Gaididei 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,42(1):103-112
We study the motion of envelope solitons on anharmonic atomic chains in the presence of dissipation and thermal fluctuations. We consider the continuum limit of the discrete system and apply an adiabatic perturbation theory which yields a system of stochastic integro-differential equations for the collective variables of the ansatz for the perturbed envelope soliton. We derive the Fokker-Planck equation of this system and search for a statistically equivalent system of Langevin equations, which shares the same Fokker-Planck equation. We undertake an analytical analysis of the Langevin system and derive an expression for the variance of the soliton position Var[x
s
] which predicts a stronger than linear time dependence of Var[x
s
] (superdiffusion). We compare these results with simulations for the discrete system and find they agree well. We refer to recent studies where the diffusion of pulse solitons were found to exhibit a superdiffusive behaviour on longer time scales.Received: 28 June 2004, Published online: 26 November 2004PACS:
05.10.Gg Stochastic analysis methods - 05.45.Yv Solitons - 05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion - 05.50. + q Lattice theory and statistics 相似文献
5.
6.
Mathias Lederer 《Annals of Combinatorics》2006,10(3):389-394
From Kostant’s multiplicity formula for general linear groups, one can derive a formula for the Kostka numbers. In this note
we give a combinatorial proof of this formula.
Received January 7, 2005 相似文献
7.
Patrick Mather Nino Grizzuti Glenn Heffner Mathias Ricker Willie E. Rochefort Markus Seitz Hans-Werner Schmidt Dale S. Pearson 《Liquid crystals》1994,17(6):811-826
In this paper, we report on the synthesis and detailed characterization of a new semiflexible nematic liquid crystalline polyester which could serve as a 'model' polyester for a variety of physical and physico-chemical investigations. The polymer is a nematic liquid over a wide temperature range-from the glass transition temperature at ∼95°C to the isotropic transition at ∼240°C. We expect this polyester to be particularly useful for studying the effect of flow on the orientation of liquid crystalline polymers, as well as the production and removal of disclinations. 相似文献
8.
9.
10.