全文获取类型
收费全文 | 3030篇 |
免费 | 401篇 |
国内免费 | 258篇 |
专业分类
化学 | 591篇 |
晶体学 | 15篇 |
力学 | 732篇 |
综合类 | 21篇 |
数学 | 127篇 |
物理学 | 2203篇 |
出版年
2024年 | 4篇 |
2023年 | 33篇 |
2022年 | 124篇 |
2021年 | 90篇 |
2020年 | 101篇 |
2019年 | 98篇 |
2018年 | 95篇 |
2017年 | 93篇 |
2016年 | 137篇 |
2015年 | 105篇 |
2014年 | 116篇 |
2013年 | 242篇 |
2012年 | 164篇 |
2011年 | 272篇 |
2010年 | 162篇 |
2009年 | 229篇 |
2008年 | 195篇 |
2007年 | 165篇 |
2006年 | 158篇 |
2005年 | 146篇 |
2004年 | 123篇 |
2003年 | 114篇 |
2002年 | 129篇 |
2001年 | 97篇 |
2000年 | 71篇 |
1999年 | 61篇 |
1998年 | 59篇 |
1997年 | 42篇 |
1996年 | 33篇 |
1995年 | 32篇 |
1994年 | 37篇 |
1993年 | 28篇 |
1992年 | 25篇 |
1991年 | 17篇 |
1990年 | 24篇 |
1989年 | 14篇 |
1988年 | 8篇 |
1987年 | 10篇 |
1986年 | 11篇 |
1985年 | 6篇 |
1984年 | 7篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1975年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有3689条查询结果,搜索用时 15 毫秒
21.
A numerical simulation is performed to investigate the flow induced by a sphere moving along the axis of a rotating cylindrical container filled with the viscous fluid. Three‐dimensional incompressible Navier–Stokes equations are solved using a finite element method. The objective of this study is to examine the feature of waves generated by the Coriolis force at moderate Rossby numbers and that to what extent the Taylor–Proudman theorem is valid for the viscous rotating flow at small Rossby number and large Reynolds number. Calculations have been undertaken at the Rossby numbers (Ro) of 1 and 0.02 and the Reynolds numbers (Re) of 200 and 500. When Ro=O(1), inertia waves are exhibited in the rotating flow past a sphere. The effects of the Reynolds number and the ratio of the radius of the sphere and that of the rotating cylinder on the flow structure are examined. When Ro ? 1, as predicted by the Taylor–Proudman theorem for inviscid flow, the so‐called ‘Taylor column’ is also generated in the viscous fluid flow after an evolutionary course of vortical flow structures. The initial evolution and final formation of the ‘Taylor column’ are exhibited. According to the present calculation, it has been verified that major theoretical statement about the rotating flow of the inviscid fluid may still approximately predict the rotating flow structure of the viscous fluid in a certain regime of the Reynolds number. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
22.
23.
24.
The K+−nucleus cross sections have been calculated in relativistic non-linear models taking into account the in-medium modifications of nucleons and mesons properties. More precisely, we have taken into account both the dressing of the nucleon effective mass by the scalar nuclear field in the target and the coupling of the mesons exchanged between the K+ and the nucleons to the polarization of the medium. First, using the most recent relativistic non-linear models, the in-medium σ, ω and ρ meson masses have been obtained in the nuclear matter rest frame. The influence of the non-linear contributions on the K+−nucleus cross sections has then been studied. Finally, we have compared our results with the experimental data. 相似文献
25.
26.
Mei‐Jiau Huang 《国际流体数值方法杂志》2005,48(5):521-539
The technique of splitting a fat vortex element (with a core width larger than some threshold) into some thin ones in order to fix the convergence problem of the core‐spreading vortex methods is convenient and efficient. In particular, it keeps the method purely Lagrangian. In the present investigation, the splitting process is further viewed as part of the physical diffusion process. A new splitting method in which several weaker child vortices surround a thinned but still strong parent vortex is proposed. It is found that because of the survival of the parent vortex, the error arising from the splitting events can be largely reduced. The computational amount on the other hand is kept reasonably large by merging similar and close‐by vortices. The merging scheme designed herein not only involves fewer restrictions but also allows merging vortices of opposite rotations through the viewpoint of remeshing. The validity and accuracy of these techniques, proposed particularly for simulations undergoing lots of splitting and merging events, are verified by successfully simulating the interactions between two Burgers vortices under an external straining field. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
27.
Summary The relative X-ray fluorescence (XRF) intensities for annular source and various annular specimen are measured with a Ge-Li
detection system and calculated by the Monte Carlo numerical techniques (MCNT).Kα X-ray intensities of annular specimens with different radii prepared from a pure-molybdenum foil are measured and it is
seen that the measured values are in good agreement with the values calculated by MCNT. The variation of the fluorescence
intensity due to the collimator radius is also studied. The differences between the MCNT and experimental results are discussed
in terms of the possible sources of errors. 相似文献
28.
S. A. Chaplygin 《Regular and Chaotic Dynamics》2007,12(2):219-232
This text presents an English translation of the significant paper [6] on vortex dynamics published by the outstanding Russian
scientist S. A. Chaplygin, which seems to have almost escaped the attention of later investigators in this field. Although
it was published more than a century ago, in our opinion it is still interesting and valuable.
__________
Originally published in: Trudy otdeleniya fizicheskikh nauk imperatorskogo Moskovskogo obshchestva lyubitelei estestvoznaniya, antropologii i etnografii
(Transactions of the Physical Section of Moscow Society of Friends of Natural Sciences, Anthropology and Ethnography), 1903, Vol. 11, No. 2, pp. 11–14. Translated from Russian by S. Ramodanov; edited by D. Blackmore; commented by V. V. Meleshko
(Department of Theoretical and Applied Mechanics, Faculty of Machanics and Mathematics, Kiev National Taras Shevchenko University,
01030 Kiev, Ukraine. E-mail: meleshko@univ.kiev.ua) and G.J.F. van Heijst (Fluid Dynamics Laboratory, Faculty of Applied Physics,
Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands. E-mail: g.j.f.v.heijst@tue.nl). 相似文献
29.
A. S. Romanov 《Theoretical and Mathematical Physics》2007,150(3):347-354
We solve the problem of the relative motion of two nearby vortices (a dipole pair) and a third vortex for different current
functions.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 150, No. 3, pp. 409–416, March, 2007. 相似文献
30.