全文获取类型
收费全文 | 2264篇 |
免费 | 51篇 |
国内免费 | 1篇 |
专业分类
化学 | 1211篇 |
晶体学 | 49篇 |
力学 | 78篇 |
数学 | 569篇 |
物理学 | 409篇 |
出版年
2023年 | 12篇 |
2022年 | 23篇 |
2021年 | 34篇 |
2020年 | 40篇 |
2019年 | 60篇 |
2018年 | 93篇 |
2017年 | 96篇 |
2016年 | 96篇 |
2015年 | 76篇 |
2014年 | 123篇 |
2013年 | 340篇 |
2012年 | 127篇 |
2011年 | 142篇 |
2010年 | 152篇 |
2009年 | 97篇 |
2008年 | 131篇 |
2007年 | 116篇 |
2006年 | 85篇 |
2005年 | 46篇 |
2004年 | 46篇 |
2003年 | 33篇 |
2002年 | 35篇 |
2001年 | 26篇 |
2000年 | 21篇 |
1999年 | 17篇 |
1998年 | 15篇 |
1997年 | 15篇 |
1996年 | 13篇 |
1995年 | 9篇 |
1994年 | 4篇 |
1991年 | 3篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 10篇 |
1985年 | 16篇 |
1984年 | 10篇 |
1983年 | 9篇 |
1982年 | 12篇 |
1981年 | 16篇 |
1980年 | 8篇 |
1979年 | 9篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1976年 | 12篇 |
1975年 | 5篇 |
1974年 | 10篇 |
1973年 | 9篇 |
1968年 | 9篇 |
排序方式: 共有2316条查询结果,搜索用时 15 毫秒
151.
In this study, electron paramagnetic resonance of γ-irradiated single crystals of N-Trifluoroacetyl-α-amino isobutyric acid (F3Ac-Aib-OH) was investigated at room temperature and analyzed for different orientations of the crystal in the magnetic field. The paramagnetic species in N-Trifluoroacetyl-α-aminoisobutyric acid was attributed to the ?F2-R radical (R= CONHC(CH3)COOH). Hyperfine coupling constants and g value were also determined. In addition, the single crystal of F3Ac-Aib-OH was UV-irradiated and paramagnetic species formed was studied at room temperature. The effects of gamma irradiation on fluoroamino acid and stability were discussed. 相似文献
152.
We construct certain Lagrange, Hermite and Birkhoff-type operators, which interpolate a given function and some of its derivatives
on the border of a triangle with one curved side, as well as some of their product and Boolean sum operators. We study the
interpolation properties and the order of accuracy (degree of exactness and precision set) of the constructed operators, respectively
the remainders of the corresponding interpolation formulas. Finally, we give some numerical examples. 相似文献
153.
154.
155.
Muhammet Tamer Koşan 《Proceedings Mathematical Sciences》2009,119(4):453-458
Let R be a commutative Noetherian ring with non-zero identity and a be a maximal ideal of R. An R-module M is called minimax if there is a finitely generated submodule N of M such that M/N is Artinian. Over a Gorenstein local ring R of finite Krull dimension, we proved that the Socle of H
a
n
(R) is a minimax R-module for each n ≥ 0. 相似文献
156.
It is shown that the group of isometries of the 3-dimensional space with respect to taxicab metric is the semi-direct product of octahedral group O h and T(3), where O h is the (Euclidean) symmetry group of the regular octahedron and T(3) is the group of all translations of the 3-dimensional space. 相似文献
157.
158.
159.
Tülin Coşkun 《Proceedings Mathematical Sciences》2000,110(4):357-362
In this work we obtain, under suitable conditions, theorems of Korovkin type for spaces with different weight, composed of
continuous functions defined on unbounded regions. These results can be seen as an extension of theorems by Gadjiev in [4]
and [5]. 相似文献
160.
M. Ionescu-Bujor A. Iordăchescu E. A. Ivanov G. Pascovici D. Ploştinaru V. Sabaiduc 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(3):291-296
The two short-lived isomeric states in112In have been reinvestigated by means of the112Cd(d, 2n) and109Ag (α, n) reactions. Measurements of delayed X- andγ-ray, lifetime and TDPAD spectra have been performed. A 6.32(3) keVγ-ray has been identified in the isomeric decay and anM1 multipolarity has been assigned to it on the basis of the measured internal conversion coefficients:α L =196(39) andα tot=231(35). TheE1+M2(δ =+0.24(4)) andE2 multipolarities have been determined for the 263 and 188 keV transitions deexciting the 8?(T 1/2=2.82(2) μs) and 7+ (T 1/2=0.93(2) μs) isomeric states, respectively. A revised isomeric decay scheme is presented. 相似文献