全文获取类型
收费全文 | 17682篇 |
免费 | 386篇 |
国内免费 | 549篇 |
专业分类
化学 | 4216篇 |
晶体学 | 59篇 |
力学 | 151篇 |
综合类 | 13篇 |
数学 | 12245篇 |
物理学 | 1933篇 |
出版年
2023年 | 57篇 |
2022年 | 111篇 |
2021年 | 95篇 |
2020年 | 143篇 |
2019年 | 383篇 |
2018年 | 395篇 |
2017年 | 261篇 |
2016年 | 231篇 |
2015年 | 238篇 |
2014年 | 448篇 |
2013年 | 1292篇 |
2012年 | 544篇 |
2011年 | 911篇 |
2010年 | 819篇 |
2009年 | 1250篇 |
2008年 | 1386篇 |
2007年 | 1358篇 |
2006年 | 1088篇 |
2005年 | 775篇 |
2004年 | 718篇 |
2003年 | 651篇 |
2002年 | 460篇 |
2001年 | 358篇 |
2000年 | 384篇 |
1999年 | 403篇 |
1998年 | 363篇 |
1997年 | 271篇 |
1996年 | 353篇 |
1995年 | 378篇 |
1994年 | 344篇 |
1993年 | 286篇 |
1992年 | 251篇 |
1991年 | 134篇 |
1990年 | 139篇 |
1989年 | 132篇 |
1988年 | 116篇 |
1987年 | 125篇 |
1986年 | 92篇 |
1985年 | 119篇 |
1984年 | 95篇 |
1983年 | 63篇 |
1982年 | 123篇 |
1981年 | 91篇 |
1980年 | 74篇 |
1979年 | 62篇 |
1978年 | 69篇 |
1977年 | 73篇 |
1976年 | 66篇 |
1975年 | 20篇 |
1974年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Piotr Niemiec 《Topology and its Applications》2006,153(18):3373-3382
Equicontinuous semigroups of transformations of a compact Hausdorff space and their sets of all invariant (Borel, regular and probabilistic) measures are studied. Conditions equivalent to the existence of at least one invariant measure are given. The (algebraic and topological) structure of the set of invariant measures is researched. 相似文献
82.
Weak vector equilibrium problems with bi-variable mappings from product space of two bounded complete locally convex Hausdorff topological vector spaces to another topological vector space are studied. The existence theorems of solutions are proved by the FKKM fixed point theorem. Viscosity principle of vector equilibrium problems is dealt with. The relations between solutions of the vector equilibrium problem and those of its perturbation problem are presented. 相似文献
83.
Yuri Bilu 《Monatshefte für Mathematik》2002,137(1):1-3
We correct an inaccuracy in the papers of Le, Mignotte, and Bugeaud on the generalized Ramanujan-Nagell equation.
Received June 23, 2001 相似文献
84.
Ion synthesis and laser annealing of Cu nanoparticles in Al2O3 总被引:1,自引:0,他引:1
A.L. Stepanov V.N. Popok D.E. Hole I.B. Khaibullin 《Applied Physics A: Materials Science & Processing》2002,74(3):441-446
Al2O3 samples with Cu nanoparticles, synthesised by ion implantation at 40 keV with a dose of 1×1017 ion/cm2 and a current density from 2.5 to 12.5 μA/cm2, were annealed using ten pulses from a KrF excimer laser with a single pulse fluence of 0.3 J/cm2. The copper depth distribution, formation and modification of metal nanoparticles under the ion implantation and laser treatment
were studied by Rutherford backscattering (RBS), energy dispersive X-ray (EDX) analysis, atomic force microscopy (AFM) and
optical spectroscopy. It was found that laser annealing leads to a reduction in the nanoparticle size without diffusion of
metal atoms into the bulk. The change in particle size and the possibility for oxidation of the copper particles are examined
in the framework of Mie theory. Calculations presented show that under excimer laser treatment, Cu nanoparticles are more
likely to be reduced in size than to undergo oxidation.
Received: 19 April 2001 / Accepted: 7 November 2001 / Published online: 23 January 2002 相似文献
85.
This paper is based on the M. Sc. thesis written by the third author under the supervision of the first two authors. It was submitted to the University of Baghdad in 1986. 相似文献
86.
Nicola Fusco Michele Gori Francesco Maggi 《NoDEA : Nonlinear Differential Equations and Applications》2006,13(4):425-433
An approximation theorem for families of weakly coercive convex functions by means of countably many smooth families of convex
functions is proved. As a consequence, the classical “three-fold” lower semicontinuity theorem for integral functionals of
the Calculus of Variations by James Serrin is unified in one single statement. 相似文献
87.
Here we prove that every compact differential manifold has a smooth algebraic model defined over Q. In dimension 2 we find an algebraic model (may be singular) defined over Q and birational over Q to the projective plane. 相似文献
88.
Scott McCullough 《Integral Equations and Operator Theory》1992,15(1):43-71
Kernels over the unit disk for which a version of Carathéodory interpolation is true are characterized in a simple computationally verifiable manner. 相似文献
89.
Hideaki Ishikawa 《Archiv der Mathematik》2002,79(6):439-448
In this paper we introduce a certain sum by using Dirichlet characters. We investigate the Riesz mean of the sum using the
analytic properties of the MultipleL-function systematically.
Eine überarbeitete Fassung ging am 6. 8. 2001 ein 相似文献
90.