全文获取类型
收费全文 | 763篇 |
免费 | 15篇 |
国内免费 | 4篇 |
专业分类
化学 | 452篇 |
晶体学 | 3篇 |
力学 | 27篇 |
数学 | 178篇 |
物理学 | 122篇 |
出版年
2023年 | 5篇 |
2022年 | 19篇 |
2021年 | 26篇 |
2020年 | 21篇 |
2019年 | 15篇 |
2018年 | 14篇 |
2017年 | 13篇 |
2016年 | 32篇 |
2015年 | 24篇 |
2014年 | 29篇 |
2013年 | 42篇 |
2012年 | 50篇 |
2011年 | 48篇 |
2010年 | 38篇 |
2009年 | 28篇 |
2008年 | 38篇 |
2007年 | 40篇 |
2006年 | 35篇 |
2005年 | 37篇 |
2004年 | 29篇 |
2003年 | 22篇 |
2002年 | 19篇 |
2001年 | 12篇 |
1999年 | 11篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 13篇 |
1995年 | 10篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1989年 | 5篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1921年 | 2篇 |
1919年 | 2篇 |
1915年 | 4篇 |
1909年 | 2篇 |
1901年 | 2篇 |
1868年 | 2篇 |
排序方式: 共有782条查询结果,搜索用时 0 毫秒
101.
Barbaro P Bianchini C Giambastiani G Oberhauser W Bonzi LM Rossi F Dal Santo V 《Dalton transactions (Cambridge, England : 2003)》2004,(12):1783-1784
New systems based on cationic chiral phosphine-rhodium complexes anchored to a commercial cation-exchange gel-type resin showed high efficiency and easy recycling in the asymmetric hydrogenation of prochiral olefins. 相似文献
102.
Filippo Bracci Roberto Tauraso Fabio Vlacci 《Journal of Mathematical Analysis and Applications》2002,270(2):1131-473
Let f,g be two commuting holomorphic self-maps of the unit disc. If f and g agree at the common Wolff point up to a certain order of derivatives (no more than 3 if the Wolff point is on the unit circle), then f≡g. 相似文献
103.
Recently, in Cammaroto et al. (2013) [4] we obtained a generalization of the famous inequality established by A.V. Arhangel?ski? in 1969 for Hausdoff spaces. In this paper, following this line of research, we present a common variation of this inequality for Urysohn spaces by developing a Main Theorem for obtaining inequalities. In particular, we extend a 2006 inequality by Hodel for Urysohn spaces. Moreover, this extended inequality is used to analyze a result containing an increasing chain of spaces that satisfies the same cardinality inequality and this new result solves an open problem in Cammaroto et al. (2013) [4] for Urysohn spaces. This general theorem also provides a new cardinal inequality for Hausdorff spaces. The paper is concluded with some open problems. 相似文献
104.
105.
Given an open bounded connected subset Ω of ℝn, we consider the overdetermined boundary value problem obtained by adding both zero Dirichlet and constant Neumann boundary
data to the elliptic equation −div(A(|∇u|)∇u)=1 in Ω. We prove that, if this problem admits a solution in a suitable weak sense, then Ω is a ball. This is obtained under
fairly general assumptions on Ω and A. In particular, A may be degenerate and no growth condition is required. Our method of proof is quite simple. It relies on a maximum principle
for a suitable P-function, combined with some geometric arguments involving the mean curvature of ∂Ω. 相似文献
106.
We discuss the stability of Yang-Mills fields in the framework of a sourceless scheme introduced by 't Hooft. We find that abelian magnetic field configurations in Yang-Mills theories are always unstable. A classification for the unstable modes is given. 相似文献
107.
C. de Lisio C. Altucci R. Bruzzese F. De Filippo S. Solimeno M. Bellini P. Foggi 《Applied physics. B, Lasers and optics》1997,64(3):323-330
We report the realization of a vacuum-ultraviolet radiation source based on high-order harmonic generation in noble-gas samples,
operating at high repetition rate. In particular, we observed up to the 13th harmonic (λ=61 nm) of the fundamental frequency
of a short pulse, high repetition rate titanium–sapphire laser after its interaction with a Xe gas jet. The effects of the
propagation of the fundamental and harmonic beams through an ionized medium are studied by analysing the spectral profile
of the 9th and 7th harmonics. Finally, we report a study of the dependence of the harmonic conversion efficiency on relative
position of the focus and the gas target.
Received: 29 March 1996/Revised version: 25 July 1996 相似文献
108.
109.
110.