全文获取类型
收费全文 | 1156篇 |
免费 | 184篇 |
国内免费 | 75篇 |
专业分类
化学 | 179篇 |
晶体学 | 2篇 |
力学 | 363篇 |
综合类 | 5篇 |
数学 | 85篇 |
物理学 | 781篇 |
出版年
2024年 | 2篇 |
2023年 | 15篇 |
2022年 | 24篇 |
2021年 | 18篇 |
2020年 | 24篇 |
2019年 | 25篇 |
2018年 | 21篇 |
2017年 | 30篇 |
2016年 | 49篇 |
2015年 | 47篇 |
2014年 | 60篇 |
2013年 | 90篇 |
2012年 | 60篇 |
2011年 | 80篇 |
2010年 | 45篇 |
2009年 | 60篇 |
2008年 | 62篇 |
2007年 | 57篇 |
2006年 | 68篇 |
2005年 | 66篇 |
2004年 | 50篇 |
2003年 | 51篇 |
2002年 | 46篇 |
2001年 | 42篇 |
2000年 | 57篇 |
1999年 | 26篇 |
1998年 | 33篇 |
1997年 | 20篇 |
1996年 | 19篇 |
1995年 | 24篇 |
1994年 | 14篇 |
1993年 | 15篇 |
1992年 | 13篇 |
1991年 | 12篇 |
1990年 | 8篇 |
1989年 | 8篇 |
1988年 | 2篇 |
1987年 | 8篇 |
1986年 | 9篇 |
1985年 | 11篇 |
1984年 | 14篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 7篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1974年 | 3篇 |
1971年 | 1篇 |
排序方式: 共有1415条查询结果,搜索用时 6 毫秒
41.
We theoretically investigate the effect of the interdot Coulomb repulsion on Kondo resonances in the series-coupled double quantum dot coupled to two ferromagnetic leads. The Hamiltonian of our system is solved by means of the slave-boson mean-field approximation, and the variation of the density of states, the transmission probability, the occupation number, and the Kondo temperature with the interdot Coulomb repulsion are discussed in the Kondo regime. The density of states is calculated for various interdot Coulomb repulsions with both parallel and antiparallel lead-polarization alignments. Our results reveal that the interdot Coulomb repulsion greatly influences the physical property of this system, and relevant underlying physics of this system is discussed. 相似文献
42.
43.
44.
¼ 《Superlattices and Microstructures》2000,28(5-6)
The metal-oxide-semiconductor (MOS) field effect transistor (FET) using ‘oxidized μ c-Si/ultrathin oxide’ gate structure was studied. It was found that this structure shows negative differential resistance behavior, which can be explained by the Coulomb blockade effect of trapped carriers and immediate tunneling into and tunneling out with gate bias variation. The requirements for the device with this structure showing negative differential resistance behavior are based on very weak resistive coupling between floating gate and channel. They are the thinness of the tunnel oxide film, the thickness ratio of the upper oxidized film and the tunnel oxide, and the channel threshold voltage. MOSFET with this gate structure is proposed as a new negative differential resistance device. 相似文献
45.
Making use of the relativistic BBGKY technique,the relativistic generalization of Landau collision integral is botained.Furthermore,we calculate the relativistic hydrodynamic modes up to the second order in the hydrodynamic wave number.Combining Resibois‘ method,we present the first principle formula of the relativistic heat conductivity of Coulumb electronic plasmas for low-order corrections. 相似文献
46.
This is a general and exact study of multiple Hamiltonian walks (HAW) filling the two-dimensional (2D) Manhattan lattice. We generalize the original exact solution for a single HAW by Kasteleyn to a system ofmultiple closed walks, aimed at modeling a polymer melt. In 2D, two basic nonequivalent topological situations are distinguished. (1) the Hamiltonian loops are allrooted andcontractible to a point:adjacent one to another, and, on a torus,homotopic to zero. (2) the loops can encircle one another and, on a torus, canwind around it. Forcase 1, the grand canonical partition function and multiple correlation functions are calculated exactly as those of multiple rooted spanningtrees or of a massive 2Dfree field, critical at zero mass (zero fugacity). The conformally invariant continuum limit on a Manhattantorus is studied in detail. The melt entropy is calculated exactly. We also consider the relevant effect of free boundary conditions. The number of single HAWs on Manhattan lattices with other perimeter shapes (rectangular, Kagomé, triangular, and arbitrary) is studied and related to the spectral theory of the Dirichlet Laplacian. This allows the calculation of exact shape-dependent configuration exponents y. An exact surface critical exponent is obtained. Forcase 2, nested and winding Hamiltonian circuits are allowed. An exact equivalence to thecritical Q-state Potts model exists, whereQ
1/2 is the walk fugacity. The Hamiltonian system is then always critical (forQ<-4). The exact critical exponents, in infinite numbers, are universal and identical to those of theO(n=Q
1/2) model in its low-temperature phase, i.e. are those of dense polymers. The exact critical partition functions on the torus are given from conformai invariance theory. These models 1 and 2 yield the two first exactly solved models of polymer melts. 相似文献
47.
48.
J. Ekman D. Rudolph C. Fahlander R.J. Charity W. Reviol D.G. Sarantites V. Tomov R.M. Clark M. Cromaz P. Fallon A.O. Macchiavelli M. Carpenter D. Seweryniak 《The European Physical Journal A - Hadrons and Nuclei》2000,9(1):13-17
Eighteen previously unknown γ-ray transitions were identified in the T
z = - 1/2 nucleus 51Fe following the fusion-evaporation reaction 32S(28Si,2α1n)51Fe. The level scheme reaches the fully aligned I
π = 27/2- terminating state of the five holes in the f
7/2 shell. The 17/2- state was found to be isomeric, and the lifetime was measured to be 2.87 ns. The mirror symmetry of 51Fe and 51Mn is discussed, and the level scheme of 51Fe is compared to shell-model calculations.
Received: 20 July 2000 / Accepted: 1 August 2000 相似文献
49.
Peter Heering 《Physics in Perspective (PIP)》2006,8(1):52-63
I discuss our replication of the wire-torsion experiments that Charles Augustin Coulomb (1736–1806) reported in a session
of the Paris Académie des Sciences in 1784. I first explain the nature and purpose of the replication method and then apply it to an analysis of Coulomb’s experiments.
I conclude by placing Coulomb’s presentation of his memoir into its specific historical contest. 相似文献
50.
Alignment of photon-induced L3 vacancies is studied in rare earth and highZ elements at energies of experimental interest, near thresholds to 60 keV, under nonrelativistic dipole approximation. Numerical
calculations of the matrix element are undertaken to produce theoretical data for comparison with the experimental findings.
The A2 values being s>0.1 at photoelectron energies <20 keV are certainly higher than 5–8% uncertainties quoted in experimental
results. Present findings are from a very basic model, hydrogen-like and can further be treated as reference to observe the
impact of screening, relativistic, multipole and retardation corrections to the model 相似文献