全文获取类型
收费全文 | 4694篇 |
免费 | 289篇 |
国内免费 | 173篇 |
专业分类
化学 | 989篇 |
晶体学 | 20篇 |
力学 | 550篇 |
综合类 | 47篇 |
数学 | 2800篇 |
物理学 | 750篇 |
出版年
2024年 | 7篇 |
2023年 | 68篇 |
2022年 | 44篇 |
2021年 | 76篇 |
2020年 | 107篇 |
2019年 | 132篇 |
2018年 | 121篇 |
2017年 | 125篇 |
2016年 | 136篇 |
2015年 | 124篇 |
2014年 | 190篇 |
2013年 | 480篇 |
2012年 | 233篇 |
2011年 | 236篇 |
2010年 | 188篇 |
2009年 | 297篇 |
2008年 | 304篇 |
2007年 | 310篇 |
2006年 | 232篇 |
2005年 | 202篇 |
2004年 | 188篇 |
2003年 | 133篇 |
2002年 | 128篇 |
2001年 | 101篇 |
2000年 | 107篇 |
1999年 | 88篇 |
1998年 | 86篇 |
1997年 | 84篇 |
1996年 | 69篇 |
1995年 | 52篇 |
1994年 | 65篇 |
1993年 | 42篇 |
1992年 | 53篇 |
1991年 | 31篇 |
1990年 | 34篇 |
1989年 | 31篇 |
1988年 | 25篇 |
1987年 | 26篇 |
1986年 | 28篇 |
1985年 | 12篇 |
1984年 | 22篇 |
1983年 | 15篇 |
1982年 | 14篇 |
1981年 | 18篇 |
1980年 | 18篇 |
1979年 | 19篇 |
1978年 | 15篇 |
1977年 | 12篇 |
1976年 | 14篇 |
1974年 | 5篇 |
排序方式: 共有5156条查询结果,搜索用时 178 毫秒
1.
《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2021,38(5):1337-1371
In this paper we consider minimizers of the functional where is a bounded open set and where are the first k eigenvalues on Ω of an operator in divergence form with Dirichlet boundary condition and with Hölder continuous coefficients. We prove that the optimal sets have finite perimeter and that their free boundary is composed of a regular part, which is locally the graph of a -regular function, and a singular part, which is empty if , discrete if and of Hausdorff dimension at most if , for some . 相似文献
2.
3.
4.
In this paper, we consider a viscoelastic wave equation of variable coefficients in the presence of past history with nonlinear damping and delay in the internal feedback and dynamic boundary conditions. Under suitable assumptions, we establish an explicit and general decay rate result without imposing restrictive assumption on the behavior of the relaxation function at infinity by Riemannian geometry method and Lyapunov functional method. 相似文献
5.
6.
Sergio Ayala‐Mar Javier Donoso‐Quezada Roberto C. Gallo‐Villanueva Victor H. Perez‐Gonzalez Jos Gonzlez‐Valdez 《Electrophoresis》2019,40(23-24):3036-3049
Exosomes are nanovesicles secreted by most cellular types that carry important biochemical compounds throughout the body with different purposes, playing a preponderant role in cellular communication. Because of their structure, physicochemical properties and stability, recent studies are focusing in their use as nanocarriers for different therapeutic compounds for the treatment of different diseases ranging from cancer to Parkinson's disease. However, current bioseparation protocols and methodologies are selected based on the final exosome application or intended use and present both advantages and disadvantages when compared among them. In this context, this review aims to present the most important technologies available for exosome isolation while discussing their advantages and disadvantages and the possibilities of being combined with other strategies. This is critical since the development of novel exosome‐based therapeutic strategies will be constrained to the effectiveness and yield of the selected downstream purification methodologies for which a thorough understanding of the available technological resources is needed. 相似文献
7.
8.
Phase field models recently gained a lot of interest in the context of tumour growth models. Typically Darcy-type flow models are coupled to Cahn–Hilliard equations. However, often Stokes or Brinkman flows are more appropriate flow models. We introduce and mathematically analyse a new Cahn–Hilliard–Brinkman model for tumour growth allowing for chemotaxis. Outflow boundary conditions are considered in order not to influence tumour growth by artificial boundary conditions. Existence of global-in-time weak solutions is shown in a very general setting. 相似文献
9.
Florence Drui Emmanuel Franck Philippe Helluy Laurent Navoret 《Comptes Rendus Mecanique》2019,347(3):259-269
The over-relaxation approach is an alternative to the Jin–Xin relaxation method in order to apply the equilibrium source term in a more precise way. This is also a key ingredient of the lattice Boltzmann method for achieving second-order accuracy. In this work, we provide an analysis of the over-relaxation kinetic scheme. We compute its equivalent equation, which is particularly useful for devising stable boundary conditions for the hidden kinetic variables. 相似文献
10.