全文获取类型
收费全文 | 11442篇 |
免费 | 384篇 |
国内免费 | 730篇 |
专业分类
化学 | 3165篇 |
晶体学 | 28篇 |
力学 | 97篇 |
综合类 | 29篇 |
数学 | 8670篇 |
物理学 | 567篇 |
出版年
2023年 | 75篇 |
2022年 | 107篇 |
2021年 | 121篇 |
2020年 | 186篇 |
2019年 | 277篇 |
2018年 | 256篇 |
2017年 | 198篇 |
2016年 | 161篇 |
2015年 | 181篇 |
2014年 | 305篇 |
2013年 | 1025篇 |
2012年 | 313篇 |
2011年 | 402篇 |
2010年 | 306篇 |
2009年 | 617篇 |
2008年 | 763篇 |
2007年 | 839篇 |
2006年 | 681篇 |
2005年 | 534篇 |
2004年 | 502篇 |
2003年 | 429篇 |
2002年 | 310篇 |
2001年 | 272篇 |
2000年 | 276篇 |
1999年 | 252篇 |
1998年 | 265篇 |
1997年 | 218篇 |
1996年 | 242篇 |
1995年 | 207篇 |
1994年 | 193篇 |
1993年 | 189篇 |
1992年 | 164篇 |
1991年 | 89篇 |
1990年 | 110篇 |
1989年 | 110篇 |
1988年 | 113篇 |
1987年 | 142篇 |
1986年 | 113篇 |
1985年 | 148篇 |
1984年 | 93篇 |
1983年 | 70篇 |
1982年 | 127篇 |
1981年 | 117篇 |
1980年 | 101篇 |
1979年 | 51篇 |
1978年 | 93篇 |
1977年 | 91篇 |
1976年 | 86篇 |
1975年 | 12篇 |
1974年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 225 毫秒
1.
《Indagationes Mathematicae》2021,32(6):1229-1239
2.
3.
《Indagationes Mathematicae》2022,33(1):218-237
We define the notion of basic set data for finite groups (building on the notion of basic set, but including an order on the irreducible characters as part of the structure), and we prove that the Springer correspondence provides basic set data for Weyl groups. Then we use this to determine explicitly the modular Springer correspondence for classical types (defined over a base field of odd characteristic , and with coefficients in a field of odd characteristic ): the modular case is obtained as a restriction of the ordinary case to a basic set. In order to do so, we compare the order on bipartitions introduced by Dipper and James with the order induced by the Springer correspondence. We provide a quick proof, by sorting characters according to the dimension of the corresponding Springer fibre, an invariant which is directly computable from symbols. 相似文献
4.
Simen Gjelseth Antonsen Arne Joakim C. Bunkan Tomas Mikoviny Yngve Stenstrøm Armin Wisthaler 《Molecular physics》2020,118(15)
The kinetics of the O3, OH and NO3 radical reactions with diazomethane were studied in smog chamber experiments employing long-path FTIR and PTR-ToF-MS detection. The rate coefficients were determined to be k CH2NN+O3?=?(3.2?±?0.4)?×?10?17 and k CH2NN+OH?=?(1.68?±?0.12)?×?10?10 cm3 molecule?1 s?1 at 295?±?3?K and 1013?±?30 hPa, whereas the CH2NN?+?NO3 reaction was too fast to be determined in the static smog chamber experiments. Formaldehyde was the sole product observed in all the reactions. The experimental results are supported by CCSD(T*)-F12a/aug-cc-pVTZ//M062X/aug-cc-pVTZ calculations showing the reactions to proceed exclusively via addition to the carbon atom. The atmospheric fate of diazomethane is discussed. 相似文献
5.
We investigate congruence classes and direct congruence classes of m-tuples in the complex projective space ℂP
n
. For direct congruence one allows only isometries which are induced by linear (instead of semilinear) mappings. We establish
a canonical bijection between the set of direct congruence classes of m-tuples of points in ℂP
n
and the set of equivalence classes of positive semidefinite Hermitean m×m-matrices of rank at most n+1 with 1's on the diagonal. As a corollary we get that the direct congruence class of an m-tuple is uniquely determined by the direct congruence classes of all of its triangles, provided that no pair of points of
the m-tuple has distance π/2. Examples show that the situation changes drastically if one replaces direct congruence classes by
congruence classes or if distances π/2 are allowed. Finally we do the same
kind of investigation also for the complex hyperbolic space ℂH
n
. Most of the results are completely analogous, however, there are also some interesting differences.
Received: 15 January 1996 相似文献
6.
7.
Peter Dräxler 《Journal of Pure and Applied Algebra》2002,169(1):33-42
We show that the cleaving functors introduced in [Bautista et al., Invent. Math. 81 (1985) 217] as a tool for proving infinite representation type of finite-dimensional algebras can also be used to establish controlled wildness. The main application is that an algebra is controlled wild if there is an indecomposable projective module with a Loewy factor having a homogeneous direct summand which is of length at least 3. As a second application we derive Han's covering criterion. 相似文献
8.
A Volterra type integral equation in a Hilbert space with an additional linear operator L and a spectral parameter depending
on time is considered. If the parameter does not belong to the spectrum of L unconditional solvability of the considered problem
is proved. In the case where the initial value of the parameter coincides with some isolated point of the spectrum of the
operator L sufficient conditions for solvability are established. The obtained results are applied to the partial integral
equations associated with a contact problem of the theory of elasticity. 相似文献
9.
Saida Sultanic 《Integral Equations and Operator Theory》2006,55(4):573-595
The central question of this paper is the one of finding the right analogue of the Commutant Lifting Theorem for the Bergman
space La2. We also analyze the analogous problem for weighted Bergman spaces La,α2, − 1 < α < ∞. 相似文献
10.
张志让 《数学年刊A辑(中文版)》2006,(2)
如果群 G 的所有真商群都是 FO-群,但是群 G 本身不是 FO-群,则称 G 为外 FO-群,本文将给出外 FO-群完全的结构描述. 相似文献