全文获取类型
收费全文 | 9587篇 |
免费 | 1220篇 |
国内免费 | 628篇 |
专业分类
化学 | 848篇 |
晶体学 | 14篇 |
力学 | 521篇 |
综合类 | 197篇 |
数学 | 7067篇 |
物理学 | 2788篇 |
出版年
2024年 | 14篇 |
2023年 | 137篇 |
2022年 | 206篇 |
2021年 | 195篇 |
2020年 | 299篇 |
2019年 | 329篇 |
2018年 | 340篇 |
2017年 | 335篇 |
2016年 | 264篇 |
2015年 | 213篇 |
2014年 | 421篇 |
2013年 | 775篇 |
2012年 | 451篇 |
2011年 | 608篇 |
2010年 | 545篇 |
2009年 | 753篇 |
2008年 | 732篇 |
2007年 | 609篇 |
2006年 | 587篇 |
2005年 | 452篇 |
2004年 | 455篇 |
2003年 | 390篇 |
2002年 | 368篇 |
2001年 | 313篇 |
2000年 | 241篇 |
1999年 | 212篇 |
1998年 | 209篇 |
1997年 | 161篇 |
1996年 | 139篇 |
1995年 | 119篇 |
1994年 | 85篇 |
1993年 | 76篇 |
1992年 | 73篇 |
1991年 | 44篇 |
1990年 | 31篇 |
1989年 | 37篇 |
1988年 | 34篇 |
1987年 | 22篇 |
1986年 | 20篇 |
1985年 | 29篇 |
1984年 | 28篇 |
1983年 | 10篇 |
1982年 | 19篇 |
1981年 | 13篇 |
1980年 | 10篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1975年 | 3篇 |
1974年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
71.
《Discrete Mathematics》2019,342(10):2846-2849
72.
In Korchmáros et al. (2018)one-factorizations of the complete graph are constructed for with any odd prime power such that either or . The arithmetic restriction is due to the fact that the vertices of in the construction are the points of a conic in the finite plane of order . Here we work on the Euclidean plane and describe an analogous construction where the role of is taken by a regular -gon. This allows us to remove the above constraints and construct one-factorizations of for every even . 相似文献
73.
Combining the dual least action principle with Mountain-pass lemma,we obtain the existence of brake orbits for first-order convex Hamiltonian systems with particular anisotropic growth. 相似文献
74.
A triangular lattice model for pattern formation by core-shell particles at fluid interfaces is introduced and studied for the particle to core diameter ratio equal to 3. Repulsion for overlapping shells and attraction at larger distances due to capillary forces are assumed. Ground states and thermodynamic properties are determined analytically and by Monte Carlo simulations for soft outer- and stiffer inner shells, with different decay rates of the interparticle repulsion. We find that thermodynamic properties are qualitatively the same for slow and for fast decay of the repulsive potential, but the ordered phases are stable for temperature ranges, depending strongly on the shape of the repulsive potential. More importantly, there are two types of patterns formed for fixed chemical potential—one for a slow and another one for a fast decay of the repulsion at small distances. In the first case, two different patterns—for example clusters or stripes—occur with the same probability for some range of the chemical potential. For a fixed concentration, an interface is formed between two ordered phases with the closest concentration, and the surface tension takes the same value for all stable interfaces. In the case of degeneracy, a stable interface cannot be formed for one out of four combinations of the coexisting phases, because of a larger surface tension. Our results show that by tuning the architecture of a thick polymeric shell, many different patterns can be obtained for a sufficiently low temperature. 相似文献
75.
A compact graph-like space is a triple , where is a compact, metrizable space, is a closed zero-dimensional subset, and is an index set such that . New characterizations of compact graph-like spaces are given, connecting them to certain classes of continua, and to standard subspaces of Freudenthal compactifications of locally finite graphs. These are applied to characterize Eulerian graph-like compacta. 相似文献
76.
77.
78.
79.
80.