全文获取类型
收费全文 | 332篇 |
免费 | 36篇 |
国内免费 | 14篇 |
专业分类
化学 | 15篇 |
力学 | 53篇 |
综合类 | 2篇 |
数学 | 71篇 |
物理学 | 241篇 |
出版年
2022年 | 5篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 8篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 10篇 |
2013年 | 12篇 |
2012年 | 6篇 |
2011年 | 12篇 |
2010年 | 8篇 |
2009年 | 14篇 |
2008年 | 15篇 |
2007年 | 46篇 |
2006年 | 24篇 |
2005年 | 17篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 24篇 |
2001年 | 8篇 |
2000年 | 21篇 |
1999年 | 17篇 |
1998年 | 18篇 |
1997年 | 8篇 |
1996年 | 13篇 |
1995年 | 7篇 |
1994年 | 9篇 |
1993年 | 7篇 |
1992年 | 7篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有382条查询结果,搜索用时 15 毫秒
141.
S. Kubono Y. Yanagisawa T. Teranishi S. Kato Y. Kishida S. Michimasa Y. Ohshiro S. Shimoura K. Ue S. Watanabe N. Yamazaki 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):217-220
An in-flight RIB separator at low energies, which is the first extensive separator at low energies, called CRIB, is just under
construction at CNS. This consists of a double-achromatic magnetic separator, a window-less gas target, and a Wien filter.
Some characteristics of the CRIB are described. Possible experimental plans are also discussed in our nuclear astrophysics
project for the study of the explosive hydrogen burning process, especially on the onset mechanism.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
142.
D. Merten U. Löring K. Kretzschmar B. Metsch H.-R. Petry 《The European Physical Journal A - Hadrons and Nuclei》2002,14(4):477-489
We compute electroweak form factors of the nucleon and photon transition form factors of non-strange baryon resonances up
to the third resonance region in a model with instanton-induced interaction. The calculation is based on the Bethe-Salpeter
equation for three light constituent quarks and is fully relativistic (U. L?ring et al., Eur. Phys. J. A 10, 309 (2001)). Static nucleon properties and photon resonance couplings are in good agreement with experiment and the Q2 behaviour of the experimentally known form factors up to large momentum transfer is accounted for.
Received: 4 April 2002 / Accepted: 2 May 2002 相似文献
143.
Yu.E. Penionzhkevich Yu.A. Muzychka S.M. Lukyanov R. Kalpakchieva N.K. Skobelev V.P. Perelygin Z. Dlouhy 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):123-127
The experimentally measured excitation functions for the fission and 4n evaporation channels are presented for the 6He + 209Bi reaction. The secondary 6He beam was produced using the special beam line (Q4DQ-spectrometer) of the U400M accelerator at FLNR, JINR. The comparison
of the obtained experimental data with similar results for the 4He + 209Bi reaction shows that in the case of the 6He + 209Bi reaction a significant enhancement of the cross-section is observed for energies above the barrier. In order to get an
agreement between the experimental data and the theoretical calculations it is necessary to reduce the Coulomb barrier by
15-20% , which corresponds to an increase of the parameter r0 of the nuclear potential up to 1.5-1.6 fm.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
144.
145.
S. E. Gorodetski A. M. Ter-Krikorov 《Computational Mathematics and Mathematical Physics》2008,48(6):946-955
For a two-dimensional dynamical system at ?∞ < t < +∞, a process describing the transition from an arbitrary neighborhood of an unstable equilibrium to a stable limit cycle is studied. The system is reduced to the Poincaré normal form. An approximate solution is constructed as a polynomial of degree 2N containing only even degrees of the small parameter ε. The functional classes to which the coefficients of this polynomial belong are described. The function space containing the exact solution differing from the approximate one by O(ε2N+1) is determined. 相似文献
146.
Toshiyuki Wakimoto 《Chemical record (New York, N.Y.)》2017,17(11):1124-1134
Considering the dynamic features of natural products, our access toward exploring the entire diversity of natural products has been quite limited. It is challenging to assess the diversity of natural products by using conventional analytical methods, even with tandem chromatographic techniques, such as LC‐MS and GC‐MS. This viewpoint is supported by the sequencing analyses of microbial genomes, which have unveiled the potential of secondary metabolite production far exceeding the number of isolated molecules. Recent advancements in metabolomics, in concert with genomics analyses, have further extended the natural product diversity, prompting growing awareness of the existence of reactive or short‐lived natural molecules. This personal account introduces some examples of the discoveries of hitherto elusive natural products, due to physico‐chemical or biological reasons, and highlights the significance of the dark matter of natural products. 相似文献
147.
Asymptotic stability and blow up for a semilinear damped wave equation with dynamic boundary conditions 总被引:1,自引:0,他引:1
In this paper we consider a multi-dimensional wave equation with dynamic boundary conditions, related to the Kelvin–Voigt damping. Global existence and asymptotic stability of solutions starting in a stable set are proved. Blow up for solutions of the problem with linear dynamic boundary conditions with initial data in the unstable set is also obtained. 相似文献
148.
149.
主要研究非线性映射函数双曲不动点的二维流形计算问题. 提出了推广的Foliation条件, 以此来衡量二维流形上的一维流形轨道的增长量, 进而控制各子流形的增长速度, 实现二维流形在各个方向上的均匀增长. 此外, 提出了一种一维子流形轨道的递归插入算法, 该算法巧妙地解决了二维流形面上网格点的插入、前像搜索, 以及网格点后续轨道计算问题, 同时插入的轨道不必从初始圆开始计算, 避免了在初始圆附近产生过多的网格点. 以超混沌三维Hénon映射和具有蝶形吸引子的Lorenz系统为例验证了算法的有效性. 相似文献
150.
针对仅有一个自由度的几何可变体系,基于大变形机构模态的特性,提出常变、瞬变的判断方法,进而对常变体系提出大变形机构模态的二元体构建算法。该算法将问题简化为类似于一元二次方程的求解,无须求解非线性超越方程组,可给出完备的模态解答和完整的解答路径及其分叉点。本法具有原理直观、公式简洁、解答完备的优点,可作为结构力学几何构造分析教学的补充内容。 相似文献