全文获取类型
收费全文 | 6093篇 |
免费 | 97篇 |
国内免费 | 30篇 |
专业分类
化学 | 3821篇 |
晶体学 | 20篇 |
力学 | 170篇 |
数学 | 1330篇 |
物理学 | 879篇 |
出版年
2022年 | 45篇 |
2020年 | 58篇 |
2016年 | 88篇 |
2015年 | 74篇 |
2014年 | 83篇 |
2013年 | 208篇 |
2012年 | 181篇 |
2011年 | 192篇 |
2010年 | 132篇 |
2009年 | 133篇 |
2008年 | 188篇 |
2007年 | 215篇 |
2006年 | 180篇 |
2005年 | 201篇 |
2004年 | 165篇 |
2003年 | 140篇 |
2002年 | 159篇 |
2001年 | 70篇 |
2000年 | 98篇 |
1999年 | 73篇 |
1998年 | 60篇 |
1997年 | 83篇 |
1996年 | 79篇 |
1995年 | 85篇 |
1994年 | 83篇 |
1993年 | 76篇 |
1992年 | 93篇 |
1991年 | 64篇 |
1990年 | 67篇 |
1989年 | 76篇 |
1988年 | 91篇 |
1987年 | 73篇 |
1986年 | 90篇 |
1985年 | 122篇 |
1984年 | 119篇 |
1983年 | 85篇 |
1982年 | 126篇 |
1981年 | 126篇 |
1980年 | 113篇 |
1979年 | 124篇 |
1978年 | 108篇 |
1977年 | 108篇 |
1976年 | 96篇 |
1975年 | 110篇 |
1974年 | 83篇 |
1973年 | 87篇 |
1972年 | 55篇 |
1971年 | 61篇 |
1970年 | 64篇 |
1966年 | 47篇 |
排序方式: 共有6220条查询结果,搜索用时 0 毫秒
111.
We study the transversal spin–spin correlations in the non-equilibrium steady state of the XY chain constructed by coupling a finite cutout of the chain to the two infinite parts to its left and right acting as thermal reservoirs at different temperatures. We prove that the spatial decay of these correlations is at least exponentially fast. 相似文献
112.
We show that local and semilocal strings in Abelian and non-Abelian gauge theories with critical couplings always reconnect classically in collision, by using moduli space approximation. The moduli matrix formalism explicitly identifies a well-defined set of the vortex moduli parameters. Our analysis of generic geodesic motion in terms of those shows right-angle scattering in head-on collision of two vortices, which is known to give the reconnection of the strings. 相似文献
113.
114.
The adhesion behavior of di-n-butyl phthalate (DBP) onto different substrates (quartz, glass, and silicon) used as wafer surfaces was studied by using an in situ UV spectrophotometric technique. The results from the closed cell experiments revealed that greatest extent of DBP adhesion occurred on the quartz chip (0.154 μg cm−2), followed in the order by the glass (0.054 μg cm−2) and silicon (0.039 μg cm−2). By means of the in situ spectrophotometric observation, application of an electrical field at 290 V cm−1 in the cell proved to be effective in inducing charging of DBP aerosols, which were consequently attracted towards the electrodes. This method can be applied to wafer storage and transport equipments to prevent wafer contamination from material outgassing representative by DBP. 相似文献
115.
Recent progress in the understanding of the high density phase of neutron stars advances the view that a substantial fraction of the matter consists of hyperons. The possible impacts of a highly attractive interaction between hyperons on the properties of compact stars are investigated. We find that a hadronic equation of state with hyperons allows for a first order phase transition to hyperonic matter. The corresponding hyperon stars can have rather small radii of R approximately equal 8 km. 相似文献
116.
117.
M. Oinonen Y. Jading U. Köster J. Lettry H. Ravn J. Äystö P. Dendooven J. Huikari A. Jokinen P.O. Lipas A. Nieminen K. Peräjärvi T. Siiskonen P. Baumann A. Huck A. Knipper M. Ramdhane G. Walter F. Didierjean V.N. Fedoseyev V.I. Mishin M. Koizumi W. Liu E. Roeckl V. Sebastian 《Hyperfine Interactions》2000,127(1-4):431-436
Resonance ionization laser ion source (RILIS) technique has been used in the β-decay studies of 59Mn and 58Zn. The importance of the RILIS for production of these elements is discussed. The properties of the low-lying levels of the
studied nuclei are discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
118.
Walter Klöpffer 《光谱学快报》2013,46(11):863-876
Energy transfer by excitons is now well established in films and solutions of aromatic polymers. Excitons in disordered systems can be considered as electronically excited states, which are transferred between the light absorbing groups in a random hopping process (the same is true in molecular crystals if, because of thermal vibrations, the coherence length of the exciton waves approaches the lattice constant and consequently the band model of the excitons breaks down). 相似文献
119.
Walter F. Love Hans D. Hochheimer Mark W. Anderson Richard N. Work Charles T. Walker 《Solid State Communications》1977,23(6):365-368
The temperature dependence of the elastic constants of NaCN has been studied by propagation of ultrasonic waves at 15 MHz and by Brillouin scattering at 3 GHz over the temperature range from 287K to 355K. c44 is observed to soften linearly with temperature as the order-disorder phase transition at 284K is approached from above. The other elastic constants also soften, except for c12 which stiffens. Considerable dispersion is seen in the values of c44 obtained ultrasonically and by Brillouin scattering. Measurements of the temperature dependence of the density are also reported. 相似文献
120.
Stephen C. Hurlock Walter J. Lafferty K. Narahari Rao 《Journal of Molecular Spectroscopy》1974,50(1-3)
The rotational structure of the ν3 fundamental of 14N16O2 has been recorded by employing a vacuum grating infrared spectrograph. The analysis has led to the assignment of over 500 R- and P-branch transitions in the spectral region 1562–1650 cm−1. Molecular constants for the upper state, 001, have been presented. No Q-branch transitions were used in the evaluation of these constants. The presently obtained
and the band center ν0 = 1616.846 cm−1 differ significantly from previous determinations. Spin splitting was observed but no information was extracted about upper state spin splitting parameters. 相似文献