全文获取类型
收费全文 | 5365篇 |
免费 | 853篇 |
国内免费 | 224篇 |
专业分类
化学 | 394篇 |
晶体学 | 5篇 |
力学 | 156篇 |
综合类 | 157篇 |
数学 | 3599篇 |
物理学 | 2131篇 |
出版年
2024年 | 5篇 |
2023年 | 48篇 |
2022年 | 149篇 |
2021年 | 339篇 |
2020年 | 227篇 |
2019年 | 183篇 |
2018年 | 174篇 |
2017年 | 192篇 |
2016年 | 220篇 |
2015年 | 156篇 |
2014年 | 325篇 |
2013年 | 404篇 |
2012年 | 264篇 |
2011年 | 325篇 |
2010年 | 331篇 |
2009年 | 361篇 |
2008年 | 336篇 |
2007年 | 359篇 |
2006年 | 303篇 |
2005年 | 251篇 |
2004年 | 208篇 |
2003年 | 184篇 |
2002年 | 143篇 |
2001年 | 115篇 |
2000年 | 108篇 |
1999年 | 64篇 |
1998年 | 82篇 |
1997年 | 62篇 |
1996年 | 58篇 |
1995年 | 71篇 |
1994年 | 57篇 |
1993年 | 32篇 |
1992年 | 27篇 |
1991年 | 25篇 |
1990年 | 24篇 |
1989年 | 29篇 |
1988年 | 21篇 |
1987年 | 17篇 |
1986年 | 13篇 |
1985年 | 27篇 |
1984年 | 16篇 |
1983年 | 14篇 |
1982年 | 19篇 |
1981年 | 9篇 |
1980年 | 8篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 7篇 |
1974年 | 6篇 |
排序方式: 共有6442条查询结果,搜索用时 15 毫秒
1.
Claudius Gros 《Entropy (Basel, Switzerland)》2021,23(2)
Human societies are characterized by three constituent features, besides others. (A) Options, as for jobs and societal positions, differ with respect to their associated monetary and non-monetary payoffs. (B) Competition leads to reduced payoffs when individuals compete for the same option as others. (C) People care about how they are doing relatively to others. The latter trait—the propensity to compare one’s own success with that of others—expresses itself as envy. It is shown that the combination of (A)–(C) leads to spontaneous class stratification. Societies of agents split endogenously into two social classes, an upper and a lower class, when envy becomes relevant. A comprehensive analysis of the Nash equilibria characterizing a basic reference game is presented. Class separation is due to the condensation of the strategies of lower-class agents, which play an identical mixed strategy. Upper-class agents do not condense, following individualist pure strategies. The model and results are size-consistent, holding for arbitrary large numbers of agents and options. Analytic results are confirmed by extensive numerical simulations. An analogy to interacting confined classical particles is discussed. 相似文献
2.
3.
In 1976 S. Hawking claimed that “Because part of the information about the state of the system is lost down the hole, the final situation is represented by a density matrix rather than a pure quantum state”. 1 This was the starting point of the popular “black hole (BH) information paradox”. 相似文献
4.
5.
Nonclassical light states are important for both conceptual and practical reasons: they are basic ingredients in testing and exploring quantum foundations, and are crucial resources in quantum technologies. Various useful criteria have been developed to detect nonclassicality in the literature, and several meaningful measures of nonclassicality have been introduced and measured experimentally. In this work, by use of a non-Hermitian generalization of the Wigner-Yanase-Dyson skew information and playing with operator ordering in evaluating average photon number, we develop a novel family of criteria for detecting nonclassicality of light based on Lieb's concavity, which is a deep and powerful result concerning interaction between quantum states and observables. We elucidate the information-theoretic as well as the physical meaning of the criteria, and illustrate their effectiveness in capturing and quantifying nonclassicality of various important light states. 相似文献
6.
采用DIS数字信息化系统,对不同浓度的蓝墨水溶液在激光光源照射下的透射平均照度及照度分布图像进行实验研究,得到了平均照度值随溶液浓度变化的规律。对不同颜色塑料膜片对白炽灯光源透过照度值及照度分布图像进行实验研究得到及其相关之规律。 相似文献
7.
8.
9.
On Quantum Team Games 总被引:2,自引:0,他引:2
E. Ahmed M. F. Elettreby A. S. Hegazi 《International Journal of Theoretical Physics》2006,45(5):880-886
Recently Liu and Simaan (2004) convex static multi-team classical games have been introduced. Here they are generalized to both nonconvex, dynamic and quantum games. Puu's incomplete information dynamical systems are modified and applied to Cournot team game. The replicator dynamics of the quantum prisoner's dilemma game is also studied. 相似文献
10.
Shunlong Luo 《Foundations of Physics》2002,32(11):1757-1772
We formulate an elementary statistical game which captures the essence of some fundamental quantum experiments such as photon polarization and spin measurement. We explore and compare the significance of the principle of maximum Shannon entropy and the principle of minimum Fisher information in solving such a game. The solution based on the principle of minimum Fisher information coincides with the solution based on an invariance principle, and provides an informational explanation of Malus' law for photon polarization. There is no solution based on the principle of maximum Shannon entropy. The result demonstrates the merits of Fisher information, and the demerits of Shannon entropy, in treating some fundamental quantum problems. It also provides a quantitative example in support of a general philosophy: Nature intends to hide Fisher information, while obeying some simple rules. 相似文献