全文获取类型
收费全文 | 1355篇 |
免费 | 66篇 |
国内免费 | 74篇 |
专业分类
化学 | 144篇 |
力学 | 41篇 |
综合类 | 2篇 |
数学 | 1123篇 |
物理学 | 185篇 |
出版年
2024年 | 4篇 |
2023年 | 27篇 |
2022年 | 22篇 |
2021年 | 29篇 |
2020年 | 34篇 |
2019年 | 50篇 |
2018年 | 35篇 |
2017年 | 18篇 |
2016年 | 22篇 |
2015年 | 27篇 |
2014年 | 62篇 |
2013年 | 161篇 |
2012年 | 57篇 |
2011年 | 87篇 |
2010年 | 80篇 |
2009年 | 114篇 |
2008年 | 89篇 |
2007年 | 93篇 |
2006年 | 55篇 |
2005年 | 53篇 |
2004年 | 55篇 |
2003年 | 41篇 |
2002年 | 38篇 |
2001年 | 27篇 |
2000年 | 28篇 |
1999年 | 27篇 |
1998年 | 40篇 |
1997年 | 24篇 |
1996年 | 24篇 |
1995年 | 18篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有1495条查询结果,搜索用时 15 毫秒
71.
Fangjun Wang Guanghui Han Zhiyuan Yu Xinning Jiang Shutao Sun Rui Chen Mingliang Ye Hanfa Zou 《Journal of separation science》2010,33(13):1879-1887
It is one of the key issues to develop powerful fractionating method to increase the identification of the low‐abundance phosphopeptides. In this study, a semi‐online 2‐D LC separation strategy based on three‐step fractionation of the enriched peptides on strong anion‐exchange trap column was developed. It was demonstrated that the sensitivity and phosphoproteome coverage obtained by this fractionating method with strong anion‐exchange trap column is much higher than those by the conventional methods based on C18 trap column. In addition, when the same amount of sample was loaded, the number of identified phosphopeptides had increased 108%. Combination of this three‐step fractionation method with RPLC‐MS/MS analysis by 300 min RP‐gradient separation was applied to phosphoproteome analysis of human liver proteins, and 853 unique phosphopeptides was positively identified from 500 μg tryptic digest of human liver proteins. After three cycles' consecutive analyses, 1554 unique phosphopeptides and 1566 phosphorylated sites were totally identified from 735 phosphorylated proteins at a false discovery rate of <1% in about 54 h of analysis time. 相似文献
72.
上海理工大学理学院\quad 上海 200093该文建立了强非线性广义 Boussinesq 方程的耗散项、波速、渐进值与波形函数的导数之间的关系.利用适当变换和待定假设方法,作者求出了上述广义 Boussinesq 方程的扭状或钟状孤波解,还求出了以前文献中未曾提到过的余弦函数的周期波解.进一步给出了波速对波形影响的结论,即:``好'广义 Boussinesq 方程的行波当波速由小变大时,波形由钟状孤波变成余弦函数周期波解;``坏'广义 Boussinesq 方程的行波当波速由小变大时,波形由余弦函数周期波解变成钟状孤波. 相似文献
73.
C. Michoski C. Mirabito C. Dawson D. Wirasaet E.J. Kubatko J.J. Westerink 《Journal of computational physics》2011,230(22):8028-8056
We study a family of generalized slope limiters in two dimensions for Runge–Kutta discontinuous Galerkin (RKDG) solutions of advection-diffusion systems. We analyze the numerical behavior of these limiters applied to a pair of model problems, comparing the error of the approximate solutions, and discuss each limiter’s advantages and disadvantages. We then introduce a series of coupled p-enrichment schemes that may be used as standalone dynamic p-enrichment strategies, or may be augmented via any in the family of variable-in-p slope limiters presented. 相似文献
75.
We show that the strong approximation property (strong AP) (respectively, strong CAP) and the weak bounded approximation property (respectively, weak BCAP) are equivalent for every Banach space. This gives a negative answer to Oja's conjecture. As a consequence, we show that each of the spaces c0 and ?1 has a subspace which has the AP but fails to have the strong AP. 相似文献
76.
77.
78.
We consider the homogeneous stochastic differential equation with unknown parameter to be estimated. We prove that the standard maximum likelihood estimate is strongly consistent under very mild conditions. The conditions for strong consistency of the discretized estimator are established as well. 相似文献
79.
80.
In this paper, we derive the existence and uniqueness of mild solutions for inhomogeneous fractional evolution equations in Banach spaces by means of the method of fractional resolvent. Furthermore, we give the necessary and sufficient conditions for the existence of strong solutions. An example of the fractional diffusion equation is also presented to illustrate our theory. 相似文献