全文获取类型
收费全文 | 123篇 |
免费 | 8篇 |
国内免费 | 6篇 |
专业分类
化学 | 2篇 |
力学 | 4篇 |
综合类 | 1篇 |
数学 | 72篇 |
物理学 | 58篇 |
出版年
2023年 | 5篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 2篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2009年 | 10篇 |
2008年 | 11篇 |
2007年 | 8篇 |
2006年 | 5篇 |
2005年 | 12篇 |
2004年 | 6篇 |
2003年 | 11篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有137条查询结果,搜索用时 31 毫秒
1.
2.
本文提出了构造Birkhoff系统守恒律的积分因子方法。首先,给出了Birkhoff方程的积分因子的定义,研究了Birkhoff系统的守恒量存在必要条件;其次,建立了系统的积分因子与守恒律的对应关系,并给出了用于确定积分因子的广义Killing方程,最后,建立了守恒定理的逆定理。文末,举例说明结果的应用。 相似文献
3.
We find out upper bounds for the first eigenvalue of the stability operator for compact constant mean curvature orientable surfaces immersed in a Riemannian Killing submersion. As a consequence, the strong stability of such surfaces is studied. We also characterize constant mean curvature Hopf tori as the only ones attaining the bound in certain cases. 相似文献
4.
Zdeněk Dušek 《Mathematische Nachrichten》2015,288(8-9):872-876
In previous papers, a fundamental affine method for studying homogeneous geodesics was developed. Using this method and elementary differential topology it was proved that any homogeneous affine manifold and in particular any homogeneous pseudo‐Riemannian manifold admits a homogeneous geodesic through arbitrary point. In the present paper this affine method is refined and adapted to the pseudo‐Riemannian case. Using this method and elementary topology it is proved that any homogeneous Lorentzian manifold of even dimension admits a light‐like homogeneous geodesic. The method is illustrated in detail with an example of the Lie group of dimension 3 with an invariant metric, which does not admit any light‐like homogeneous geodesic. 相似文献
5.
Xing Wang Shao-Feng Wu Shu Zhu Jin-Hua Yue Guo-Hong Yang 《International Journal of Theoretical Physics》2008,47(5):1230-1239
Using the relationship between the entropy and the Euler characteristic, an entropy density is introduced to describe the
inner topological structure of the entropy of 4-dimensional axisymmetric black holes. It is pointed out that the density of
entropy is determined by the singularities of the timelike Killing vector field of spacetime, and these singularities carry
the topological numbers, Hopf indices and Brouwer degrees, which are topological invariants. At last, Kerr–Newman black hole
as an example of axisymmetric black holes is given. What’s more, the entropy and the latent heat of the topological phase
transition of the black hole mentioned above are calculated and the latent heat just lies in the range of the energy of gamma
ray bursts.
This work is supported in part by the NSFs of China under Grant No. 10575068 and of Shanghai Municipal Committee of Science
and Technology under Grant No. 04ZR14059 and Shanghai Leading Academic Discipline Project under Project Number: T0104. 相似文献
6.
7.
The trace identity is extended to the general loop algebra. The
Hamiltonian structures of the integrable systems concerning vector
spectral problems and the multi-component integrable hierarchy can be
worked out by using the extended trace identity. As its
application, we have obtained the Hamiltonian structures of the Yang
hierarchy, the Korteweg-de--Vries (KdV) hierarchy, the
multi-component Ablowitz--Kaup--Newell--Segur (M-AKNS) hierarchy, the
multi-component Ablowitz--Kaup--Newell--Segur Kaup--Newell
(M-AKNS--KN) hierarchy and a new multi-component integrable hierarchy
separately. 相似文献
8.
We consider here the problem of the existence of a quasi-invariant which is linear in the momenta for Hamiltonians in three
degrees of freedom. We show that such quasi-invariants are more constrained in their structure than in the two degrees of
freedom case. We also show that some of these quasi-invariants have to be interpreted as ‘pseudo-translations’, i.e., as translations
in a non-orthogonal system of coordinates. 相似文献
9.
Wei Wang 《Journal of Mathematical Analysis and Applications》2008,345(2):777-782
We prove the Korn's inequality for the conformal Killing operator on pseudo-Euclidean space Rp,q, and an existence theorem for solutions to the non-homogeneous conformal Killing equation, which is a pseudo-Euclidean conformal generalization of Donati's theorem for Euclidean Killing operator. 相似文献
10.
Christian Bär 《Annals of Global Analysis and Geometry》2009,36(1):67-79
We extend several classical eigenvalue estimates for Dirac operators on compact manifolds to noncompact, even incomplete manifolds.
This includes Friedrich’s estimate for manifolds with positive scalar curvature as well as the author’s estimate on surfaces.
相似文献