全文获取类型
收费全文 | 235篇 |
免费 | 9篇 |
国内免费 | 1篇 |
专业分类
化学 | 134篇 |
晶体学 | 2篇 |
力学 | 18篇 |
数学 | 13篇 |
物理学 | 78篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 6篇 |
2014年 | 16篇 |
2013年 | 27篇 |
2012年 | 15篇 |
2011年 | 12篇 |
2010年 | 11篇 |
2009年 | 13篇 |
2008年 | 8篇 |
2007年 | 12篇 |
2006年 | 8篇 |
2005年 | 10篇 |
2004年 | 12篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1972年 | 2篇 |
排序方式: 共有245条查询结果,搜索用时 15 毫秒
1.
We consider a quark model based on QCD scale anomaly in which the quarks move in the field of an effective glueball field.
Hadrons correspond to solitonic bags of higher energy density in a nonperturbative sea of condensed gluons. We calculate the
static properties of nucleon in this model and find that the nucleon mass is far too large (2.4–4 GeV) and the proton charge
radius (0.37–0.54 fm) is low. The proton gyromagnetic ratio and gA/gv are in reasonable agreement with the experimental numbers. 相似文献
2.
3.
Delayed feedbacks are quite common in many physical and biological systems and in particular many physiological systems. Delay
can cause a stable system to become unstable and vice versa. One of the well-studied non-biological chemical oscillators is
the Belousov-Zhabotinskii (BZ) reaction. This gives relaxation oscillations for a considerable period of time under batch
conditions. This paper deals with the effect of perturbing the limit cycle oscillation of BZ reaction by employing a delayed
electrical feedback to the system under batch conditions. The parameters chosen to study are external resistance and delay.
For various resistances and delays the system was electrically perturbed and found to exhibit various complex mixed mode oscillations.
The dynamic features are accounted for by the Oregonator model, with time delay incorporated in one of the variables.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
5.
6.
7.
8.
Optimal utilization of computational resources mandates spatio-temporal variation in resolution for computing complex engineering flows. Closure modeling in regions bridging between different resolutions is rendered difficult due to changing interactions between resolved and unresolved fields. We develop a closure model for the bridging region based on energy conservation principles. Then we proceed to provide a proof of concept in decaying isotropic turbulence with temporally varying resolution. The simplicity of the flow permits a thorough examination of various aspects of the proposed closure not feasible in more complex flows. The results demonstrate the potential promise of the approach, but more validation studies need to be performed.While the present development is in the context of partially averaged Navier–Stokes (PANS) method, the closure principle should apply for other variable-resolution (VR) approaches. 相似文献
9.
10.
Alula Melisew Tadele Krishnan Sriram Hendricks Nicolette R. Karamchand Leshern Blackburn Jonathan M 《Mikrochimica acta》2017,184(1):219-227
Microchimica Acta - The authors present a fast and sensitive surface-enhanced Raman spectroscopy (SERS) method for the determination of Mycobacterium smegmatis. It is based on the formation of... 相似文献