全文获取类型
收费全文 | 2023篇 |
免费 | 196篇 |
国内免费 | 187篇 |
专业分类
化学 | 279篇 |
晶体学 | 8篇 |
力学 | 136篇 |
综合类 | 24篇 |
数学 | 323篇 |
物理学 | 436篇 |
综合类 | 1200篇 |
出版年
2024年 | 5篇 |
2023年 | 19篇 |
2022年 | 35篇 |
2021年 | 32篇 |
2020年 | 38篇 |
2019年 | 52篇 |
2018年 | 56篇 |
2017年 | 39篇 |
2016年 | 64篇 |
2015年 | 77篇 |
2014年 | 93篇 |
2013年 | 139篇 |
2012年 | 132篇 |
2011年 | 137篇 |
2010年 | 106篇 |
2009年 | 133篇 |
2008年 | 136篇 |
2007年 | 128篇 |
2006年 | 130篇 |
2005年 | 102篇 |
2004年 | 86篇 |
2003年 | 88篇 |
2002年 | 108篇 |
2001年 | 92篇 |
2000年 | 55篇 |
1999年 | 54篇 |
1998年 | 52篇 |
1997年 | 33篇 |
1996年 | 31篇 |
1995年 | 28篇 |
1994年 | 28篇 |
1993年 | 18篇 |
1992年 | 11篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 12篇 |
1988年 | 12篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有2406条查询结果,搜索用时 31 毫秒
891.
892.
The symmetry constraint and binary nonlinearization of Lax pairs for the super classical-Boussinesq hierarchy is obtained.Under the obtained symmetry constraint,the n-th flow of the super classical-Boussinesq hierarchy is decomposed into two super finite-dimensional integrable Hamiltonian systems,defined over the super-symmetry manifold with the corresponding dynamical variables x and t n.The integrals of motion required for Liouville integrability are explicitly given. 相似文献
893.
Bursting oscillation in CO oxidation with small excitation and the enveloping slow-fast analysis method
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Based on the traditional scheme for a nonlinear system with multiple time scales,the enveloping slow-fast analysis method is developed in the paper,which can be employed to investigate the dynamics of nonlinear fields with multiple time scales with periodic excitation.Upon using the method,the behaviors of the kinetic model of CO oxidation on the platinum group metals have been explored in detail.Two typical bursting phenomena such as Fold/Fold/Hopf bursting and Fold/Fold bursting,are presented,the bifurcation mechanisms of which have been obtained.Furthermore,the dynamic difference between the two cases corresponding to relatively large and small perturbation frequencies,respectively,has been presented,which can be used to describe the influence of the frequencies involving in the evolution on the bursting behaviors in the system. 相似文献
894.
This study aims at figuring out the crucial topological ingredients which affect the outcomes of the ultimatum game located on different networks, encompassing the regular network, the random network, the small-world network, and the scale-free network. With the aid of random interchanging algorithm, we investigate the relations between the outcomes of the ultimatum game and some topological ingredients, including the average range, the clustering coefficient and the heterogeneity, and so forth. It is found that for the regular, random and small-work networks, the average range and the clustering coefficient have evident impacts on the ultimatum game, while for the scale-free network, the original degree heterogeneity and the underlying rich-club characterizations are the mainly important topological ingredients that influence the outcomes of ultimatum game substantially. 相似文献
895.
Zheng-Lin Jia 《International Journal of Theoretical Physics》2009,48(1):226-231
The effects of the time delay on the stationary properties of a triple-well potential system driven by the cross-correlated
multiplicative and additive noises are investigated. The stationary probability distribution function (SPDF) is obtained by
means of a numerical simulation method. The results indicate that: (i) The time delay can induce the reentrance phenomenon
with increasing the delay time; (ii) The cross-correlation between the multiplicative and additive noises induces the symmetry
breaking of the SPDF. 相似文献
896.
The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal field is studied within the mean-field theory. The phase diagrams and magnetization curves are obtained by diagonalizing the Hamiltonian Hi of the Ising system numerically, and the first order-order phase transitions, the first order-disorder phase transitions, and the second-order phase transitions are discussed in details. Reentrant phenomena occur when the value of the transverse field is not zero and the reentrant diagram is given. 相似文献
897.
爆炸自紧残余应力及对构件疲劳强度的影响 总被引:5,自引:0,他引:5
用贴腻子炸药法和动液压法两种爆轰工艺对不同类型厚壁构件实施了爆炸自增强处理,并对爆炸处理形成的残余应力进行了实验测定。对内壁有缺口和裂缝的厚壁圆环以及带缺口的超高压圆筒和四通构件进行了爆炸自紧处理并进行了疲劳实验检验,结果是:在高周疲劳阶段,经爆炸处理的构件缺口根部疲劳裂纹萌生寿命可提高5倍,内压疲劳开裂寿命可提高8~10倍。在低周塑性疲劳阶段构件的疲劳开裂寿命仍可提高1倍左右。由于用贴腻子炸药方法可使构件表面硬度增加从而获得更高的残余压应力,故其自增强效果优于动液压法。 相似文献
898.
899.
900.
概述了颗粒物质领域中粮仓现象和巴西坚果效应两个典型现象及其解释理论,分析其理论的成功和不足,并给出一些看法。 相似文献