全文获取类型
收费全文 | 1117篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
化学 | 353篇 |
晶体学 | 9篇 |
力学 | 79篇 |
数学 | 175篇 |
物理学 | 504篇 |
出版年
2021年 | 21篇 |
2020年 | 13篇 |
2019年 | 24篇 |
2018年 | 37篇 |
2017年 | 30篇 |
2016年 | 38篇 |
2014年 | 20篇 |
2013年 | 35篇 |
2012年 | 34篇 |
2011年 | 28篇 |
2010年 | 31篇 |
2009年 | 27篇 |
2008年 | 31篇 |
2007年 | 34篇 |
2006年 | 50篇 |
2005年 | 26篇 |
2004年 | 22篇 |
2003年 | 23篇 |
2002年 | 22篇 |
2001年 | 26篇 |
2000年 | 26篇 |
1999年 | 12篇 |
1998年 | 25篇 |
1997年 | 13篇 |
1996年 | 17篇 |
1995年 | 18篇 |
1994年 | 10篇 |
1992年 | 12篇 |
1991年 | 11篇 |
1990年 | 24篇 |
1989年 | 10篇 |
1988年 | 19篇 |
1987年 | 23篇 |
1986年 | 15篇 |
1985年 | 27篇 |
1984年 | 22篇 |
1983年 | 14篇 |
1982年 | 14篇 |
1981年 | 15篇 |
1980年 | 15篇 |
1979年 | 14篇 |
1978年 | 15篇 |
1976年 | 12篇 |
1975年 | 17篇 |
1974年 | 15篇 |
1973年 | 11篇 |
1970年 | 14篇 |
1969年 | 10篇 |
1968年 | 15篇 |
1967年 | 13篇 |
排序方式: 共有1120条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
R. G. Bulgakov V. N. Yakovlev G. A. Tolstikov V. P. Kazakov 《Russian Chemical Bulletin》1990,39(10):2230-2230
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, p. 2458, October, 1990. 相似文献
105.
106.
A. V. Yakovlev 《Journal of Mathematical Sciences》1990,52(3):3206-3216
It is proved that ifr
1
,r
2
, ...,r
s
;l
1
,l
2
, ...,l
t
are the ranks of the indecomposable summands of two direct decompositions of a torsion-free Abelian group of finite rank
and if s0 is the number of units among the numbers ri, while t0 is the number of units among the numbers lj, thenr
i
⩽n - t
0
,l
j
⩽n−s
0
for all i, j. Moreover, if for some i we have ri=n−t0, then among the lj's only one term is different from 1 and it is equal to n−t0; similarly if lj=n−s0 for some j. In addition, a construction is presented, allowing to form, from several indecomposable groups, a new group,
called a flower group, and it is proved that a flower group is indecomposable under natural restrictions on its defining parameters.
Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR,
Vol. 160, pp. 272–285, 1987. 相似文献
107.
108.
A. V. Yakovlev 《Journal of Mathematical Sciences》2006,134(6):2598-2601
Relationship between the concordance condition and the solvability of the problem of embedding a cyclic Galois extension into
another cyclic Galois extension is investigated. Bibliography: 4 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 319, 2004, pp. 293–299. 相似文献
109.
L. I. Burov A. S. Gorbatsevich M. Jadan V. V. Sherstnev Yu. P. Yakovlev 《Journal of Applied Spectroscopy》2011,78(5):733-737
We have used numerical modeling to study the effect of diffusion and fluctuations in the nonequilibrium carrier density in
the active layer of injection lasers based on an InAsSb/InAsSbP heterostructure on the angular distribution of the output
intensity. We show that diffusion smoothes out the nonequilibrium carrier distribution in the active layer, and the fundamental
lasing mode is stable over a much broader range of stripe contact widths. At the same time, diffusional processes can lead
to formation of local regions with a jump in the density of nonequilibrium charge carriers, fluctuations in which can act
as a source of instability for the fundamental lasing mode. Analysis of the numerical modeling results gives qualitative agreement
with experimental data on the dependence of the angular distribution of the output radiation for different stripe contact
widths. 相似文献
110.
This paper investigates the short-living absorption and the emission of CsI(Na) under a pulsed electron beam (Еe=0.25 MeV, t1/2=15 ns and W=0.003…0.16 J/cm2). The bands of singlet self-trapped excitons, as well as Na0 and Vk color centers have been detected in the transient absorption spectrum of CsI(Na). It has been found that the activator luminescence spectrum, peaking at 3.0 eV, fits a Gaussian (Em=3.0 eV and FWHM=0.44±0.02 eV at 80 K) and remains the same at different time delays within 10−8-10−3 s. The decay kinetics of the 3.0 eV emission has one nanosecond exponential component and two microsecond ones with time constants 1.0 and 3.0 μs, which remain unchanged within 78-150 K. It is concluded that the activator emission is due to the radiative annihilation of sodium-perturbed two halide excitons from the non-relaxed singlet state. The pathways of such excitons creation are discussed. 相似文献