全文获取类型
收费全文 | 5469篇 |
免费 | 379篇 |
国内免费 | 509篇 |
专业分类
化学 | 386篇 |
晶体学 | 4篇 |
力学 | 210篇 |
综合类 | 89篇 |
数学 | 4306篇 |
物理学 | 1362篇 |
出版年
2024年 | 8篇 |
2023年 | 45篇 |
2022年 | 92篇 |
2021年 | 113篇 |
2020年 | 131篇 |
2019年 | 132篇 |
2018年 | 154篇 |
2017年 | 142篇 |
2016年 | 162篇 |
2015年 | 108篇 |
2014年 | 258篇 |
2013年 | 462篇 |
2012年 | 198篇 |
2011年 | 282篇 |
2010年 | 249篇 |
2009年 | 304篇 |
2008年 | 412篇 |
2007年 | 363篇 |
2006年 | 330篇 |
2005年 | 299篇 |
2004年 | 238篇 |
2003年 | 257篇 |
2002年 | 257篇 |
2001年 | 199篇 |
2000年 | 171篇 |
1999年 | 156篇 |
1998年 | 166篇 |
1997年 | 127篇 |
1996年 | 106篇 |
1995年 | 69篇 |
1994年 | 54篇 |
1993年 | 35篇 |
1992年 | 34篇 |
1991年 | 19篇 |
1990年 | 33篇 |
1989年 | 18篇 |
1988年 | 21篇 |
1987年 | 12篇 |
1986年 | 15篇 |
1985年 | 17篇 |
1984年 | 15篇 |
1983年 | 9篇 |
1982年 | 16篇 |
1981年 | 8篇 |
1980年 | 12篇 |
1979年 | 9篇 |
1978年 | 10篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1973年 | 4篇 |
排序方式: 共有6357条查询结果,搜索用时 15 毫秒
101.
The
-algebras A{q
i}, generated by generalised quon commutation relations are considered. The nuclearity of these algebras is proved. It is shown that A{q
i}, is isomorphic to the extension of a higher-dimensional noncommutative torus. Irreducible representations of A{q
i}, are considered. It is shown that the Fock representation is faithful. 相似文献
102.
Wenchang Chu 《Mathematical Methods in the Applied Sciences》2023,46(1):830-839
An expansion formula into bivariate formal power series is established that implies, as consequences, three remarkable identities of partial theta functions due to Warnaar (2003), Schilling–Warnaar (2002) and Andrews–Warnaar (2007). 相似文献
103.
Nonlinear systems with correlated stochastic parameters are approximated by simpler systems. This method is an extension of an earlier version of statistical replacement and statistical linearization. The extended method is applicable to systems with correlated fluctuations. We show how this general method reduces to the earlier methods in special cases. 相似文献
104.
The explicit expressions for indecomposable representations of nine square-root Lie algebras of vector type, Rνλ (ν, λ=0, ±1),
are obtained on the space of universal enveloping algebra of two-state Heisenberg-Weyl algebra, the invariant subspaces and the quotient spaces.
From Fock representations corresponding to these indecomposable representations, the inhomogeneous
boson realizations of Rνλ
are given. The expectation values of Rνλ in the angular momentum
coherent states are calculated as well as the corresponding classical limits. 相似文献
105.
We prove some results concerning the decay of connectivities in the low-temperature phase of the two-dimensional Ising model. These provide the bounds necessary to establish, nonperturbatively, large-deviation properties for block magnetizations in these systems. We also obtain estimates on the rate at which the finite-volume, plus-boundary-condition expectation of the spin at the origin converges to the spontaneous magnetization.On leave from São Paulo University, Brazil. 相似文献
106.
107.
We find the existence of a quantum thermal effect, “Hawking absorption.” near the inner horizon of the Kerr–Newman black hole. Redefining the entropy, temperature, angular velocity, and electric potential of the black hole, we give a new formulation of the Bekenstein–Smarr formula. The redefined entropy vanishes for absolute zero temperature of the black hole and hence it is interpreted as the Planck absolute entropy of the KN black hole. 相似文献
108.
In this paper we discuss thermodynamics parameters of black hole horizon and cosmological horizon in general high-dimensional space-time. We obtain that the entropy of a cosmological horizon can be described by the Cardy-Verlinde formula. However, the entropy of black hole horizon will be expressed in a form of the Cardy-Verlinde formula, if one adopts the methods given by Abbott and Deser to compute the mass of a black hole in general high-dimensional space-time. Through discussion, relation among various thermodynamics parameters of the black hole in general high-dimensional space-time is given. That is, differential formula of the first law of thermodynamics is obtained. Because we discuss the general high-dimensional space-time, our result has universality.
PACS: 04.20.Dw, 97.60.Lf 相似文献
109.
In this Letter, a generalized Tu formula is firstly presented to construct Hamiltonian structures of fractional soliton equations. The obtained results can be reduced to the classical Hamiltonian hierarchy of AKNS in ordinary calculus. 相似文献
110.
Iddo Eliazar 《Physica A》2011,390(4):699-706
This paper explores an elemental connection between call options-the most commonly tradable financial derivatives, implied volatility term structures-critical “market information” emanating from call-option prices, and the Pietra index-a quantitative economic measure of societal egalitarianism. Our study: (i) unveils an intrinsic “Pietra structure” of call-option prices; (ii) introduces the notion of the “Pietra term structures” of financial assets; (iii) describes the probabilistic meaning of the Pietra term structures; (iv) establishes an explicit nonlinear one-to-one mapping between the Pietra term structures and the implied volatility term structures of financial assets. The results presented in this paper provide a deep insight into the econophysics of call options and implied volatility term structures. 相似文献