全文获取类型
收费全文 | 12666篇 |
免费 | 1237篇 |
国内免费 | 1598篇 |
专业分类
化学 | 978篇 |
晶体学 | 27篇 |
力学 | 722篇 |
综合类 | 358篇 |
数学 | 11088篇 |
物理学 | 2328篇 |
出版年
2024年 | 18篇 |
2023年 | 130篇 |
2022年 | 159篇 |
2021年 | 212篇 |
2020年 | 279篇 |
2019年 | 307篇 |
2018年 | 286篇 |
2017年 | 353篇 |
2016年 | 374篇 |
2015年 | 295篇 |
2014年 | 526篇 |
2013年 | 856篇 |
2012年 | 532篇 |
2011年 | 743篇 |
2010年 | 703篇 |
2009年 | 902篇 |
2008年 | 956篇 |
2007年 | 1030篇 |
2006年 | 822篇 |
2005年 | 786篇 |
2004年 | 597篇 |
2003年 | 649篇 |
2002年 | 555篇 |
2001年 | 463篇 |
2000年 | 517篇 |
1999年 | 437篇 |
1998年 | 423篇 |
1997年 | 334篇 |
1996年 | 255篇 |
1995年 | 143篇 |
1994年 | 155篇 |
1993年 | 92篇 |
1992年 | 81篇 |
1991年 | 62篇 |
1990年 | 57篇 |
1989年 | 35篇 |
1988年 | 40篇 |
1987年 | 26篇 |
1986年 | 20篇 |
1985年 | 47篇 |
1984年 | 45篇 |
1983年 | 17篇 |
1982年 | 34篇 |
1981年 | 23篇 |
1980年 | 24篇 |
1979年 | 30篇 |
1978年 | 15篇 |
1977年 | 17篇 |
1976年 | 10篇 |
1936年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
2.
ABSTRACTThe Coupled-Cluster (CC) theory is one of the most successful high precision methods used to solve the stationary Schrödinger equation. In this article, we address the mathematical foundation of this theory with focus on the advances made in the past decade. Rather than solely relying on spectral gap assumptions (non-degeneracy of the ground state), we highlight the importance of coercivity assumptions – Gårding type inequalities – for the local uniqueness of the CC solution. Based on local strong monotonicity, different sufficient conditions for a local unique solution are suggested. One of the criteria assumes the relative smallness of the total cluster amplitudes (after possibly removing the single amplitudes) compared to the Gårding constants. In the extended CC theory the Lagrange multipliers are wave function parameters and, by means of the bivariational principle, we here derive a connection between the exact cluster amplitudes and the Lagrange multipliers. This relation might prove useful when determining the quality of a CC solution. Furthermore, the use of an Aubin–Nitsche duality type method in different CC approaches is discussed and contrasted with the bivariational principle. 相似文献
3.
4.
AbstractRealistic stochastic modeling is increasingly requiring the use of bounded noises. In this work, properties and relationships of commonly employed bounded stochastic processes are investigated within a solid mathematical ground. Four families are object of investigation: the Sine-Wiener (SW), the Doering–Cai–Lin (DCL), the Tsallis–Stariolo–Borland (TSB), and the Kessler–Sørensen (KS) families. We address mathematical questions on existence and uniqueness of the processes defined through Stochastic Differential Equations, which often conceal non-obvious behavior, and we explore the behavior of the solutions near the boundaries of the state space. The expression of the time-dependent probability density of the Sine-Wiener noise is provided in closed form, and a close connection with the Doering–Cai–Lin noise is shown. Further relationships among the different families are explored, pathwise and in distribution. Finally, we illustrate an analogy between the Kessler–Sørensen family and Bessel processes, which allows to relate the respective local times at the boundaries. 相似文献
5.
6.
7.
Boundedness of commutators on homogeneous Herz spaces 总被引:9,自引:0,他引:9
The boundedness on homogeneous Herz spaces is established for a large class of linear commutators generated by BMO(R
n
) functions and linear operators of rough kernels which include the Calderón-Zygmund operators and the Ricci-Stein oRfiUatory
singular integrals with rough kernels.
Project supponed in pan by the National h’atural Science Foundation of China (Grant No. 19131080) and the NEDF of China. 相似文献
8.
Nobuaki Obata 《Acta Appl Math》1997,47(1):49-77
A general theory of operators on Boson Fock space is discussed in terms of the white noise distribution theory on Gaussian space (white noise calculus). An integral kernel operator is generalized from two aspects: (i) The use of an operator-valued distribution as an integral kernel leads us to the Fubini type theorem which allows an iterated integration in an integral kernel operator. As an application a white noise approach to quantum stochastic integrals is discussed and a quantum Hitsuda–Skorokhod integral is introduced. (ii) The use of pointwise derivatives of annihilation and creation operators assures the partial integration in an integral kernel operator. In particular, the particle flux density becomes a distribution with values in continuous operators on white noise functions and yields a representation of a Lie algebra of vector fields by means of such operators. 相似文献
9.
I.K. Argyros 《Applied Mathematics Letters》1997,10(6):21-28
In this note, we use inexact Newton-like methods to find solutions of nonlinear operator equations on Banach spaces with a convergence structure. Our technique involves the introduction of a generalized norm as an operator from a linear space into a partially ordered Banach space. In this way, the metric properties of the examined problem can be analyzed more precisely. Moreover, this approach allows us to derive from the same theorem, on the one hand, semilocal results of Kantorovich-type, and on the other hand, global results based on monotonicity considerations. By imposing very general Lipschitz-like conditions on the operators involved, on the one hand, we cover a wider range of problems, and on the other hand, by choosing our operators appropriately, we can find sharper error bounds on the distances involved than before. Furthermore, we show that special cases of our results reduce to the corresponding ones already in the literature. Finally, several examples are being provided where our results compare favorably with earlier ones. 相似文献
10.
This paper through discussing subdifferentiability and convexity of convex functions shows that a Banach space admits an equivalent
uniformly [locally uniformly, strictly] convex norm if and only if there exists a continuous uniformly [locally uniformly,
strictly] convex function on some nonempty open convex subset of the space and presents some characterizations of super-reflexive
Banach spaces.
Supported by NSFC 相似文献