全文获取类型
收费全文 | 10833篇 |
免费 | 898篇 |
国内免费 | 788篇 |
专业分类
化学 | 2290篇 |
晶体学 | 71篇 |
力学 | 1559篇 |
综合类 | 80篇 |
数学 | 6406篇 |
物理学 | 2113篇 |
出版年
2024年 | 14篇 |
2023年 | 129篇 |
2022年 | 171篇 |
2021年 | 205篇 |
2020年 | 304篇 |
2019年 | 277篇 |
2018年 | 249篇 |
2017年 | 298篇 |
2016年 | 338篇 |
2015年 | 279篇 |
2014年 | 418篇 |
2013年 | 990篇 |
2012年 | 442篇 |
2011年 | 548篇 |
2010年 | 435篇 |
2009年 | 654篇 |
2008年 | 680篇 |
2007年 | 692篇 |
2006年 | 566篇 |
2005年 | 488篇 |
2004年 | 429篇 |
2003年 | 392篇 |
2002年 | 342篇 |
2001年 | 330篇 |
2000年 | 314篇 |
1999年 | 275篇 |
1998年 | 315篇 |
1997年 | 240篇 |
1996年 | 197篇 |
1995年 | 166篇 |
1994年 | 156篇 |
1993年 | 139篇 |
1992年 | 121篇 |
1991年 | 90篇 |
1990年 | 87篇 |
1989年 | 73篇 |
1988年 | 72篇 |
1987年 | 65篇 |
1986年 | 66篇 |
1985年 | 55篇 |
1984年 | 59篇 |
1983年 | 36篇 |
1982年 | 57篇 |
1981年 | 37篇 |
1980年 | 53篇 |
1979年 | 47篇 |
1978年 | 31篇 |
1977年 | 27篇 |
1976年 | 34篇 |
1974年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
《Progress in Surface Science》2022,97(3):100663
High-reflective multilayer laser coatings are widely used in advanced optical systems from high power laser facilities to high precision metrology systems. However, the real interface quality and defects will significantly affect absorption/scattering losses and laser induced damage thresholds of multilayer coatings. With the recent advances in the control of coating design and deposition processes, these coating properties can be significantly improved when properly engineered the interface and defects. This paper reviews the recent progress in the physics of laser damage, optical losses and environmental stability involved in multilayer reflective coatings for high power nanosecond near-infrared lasers. We first provide an overview of the layer growth mechanisms, ways to control the microstructures and reduce layer roughness, as well as the nature of defects which are critical to the optical loss and laser induced damage. Then an overview of interface engineering based on the design of coating structure and the regulation of deposition materials reveals their ability to improve the laser induced damage threshold, reduce the backscattering, and realize the desirable properties of environmental stability and exceptional multifunctionality. Moreover, we describe the recent progress in the laser damage and scattering mechanism of nodule defects and give the approaches to suppress the defect-induced damage and scattering of the multilayer laser coatings. Finally, the present challenges and limitations of high-performance multilayer laser coatings are highlighted, along with the comments on likely trends in future. 相似文献
3.
This paper infers from a generalized Picone identity the uniqueness of the stable positive solution for a class of semilinear equations of superlinear indefinite type, as well as the uniqueness and global attractivity of the coexistence state in two generalized diffusive prototypes of the symbiotic and competing species models of Lotka–Volterra. The optimality of these uniqueness theorems reveals the tremendous strength of the Picone identity. 相似文献
4.
5.
In this article, we construct and analyze a residual-based a posteriori error estimator for a quadratic finite volume method (FVM) for solving nonlinear elliptic partial differential equations with homogeneous Dirichlet boundary conditions. We shall prove that the a posteriori error estimator yields the global upper and local lower bounds for the norm error of the FVM. So that the a posteriori error estimator is equivalent to the true error in a certain sense. Numerical experiments are performed to illustrate the theoretical results. 相似文献
6.
Self-assembly is a versatile bottom-up approach for fabricating novel supramolecular materials with well-defined nano- or micro-structures associated with functionalities. The oil-water interface provides an ideal venue for molecular and colloidal self-assembly. This paper gives an overview of various self-assembled materials, including nanoparticles, polymers, proteins, and lipids, at the oil-water interface. Focus has been given to fundamental principles and strategies for engineering the self-assembly process, such as control of pH, ionic strength and use of external fields, to achieve complex soft materials with desired functionalities, such as nanoparticle surfactants, structured liquids, and proteinosomes. It has been shown that self-assembly at the oil-water interface holds great promise for developing well-structured complex materials useful for many research and industrial applications. 相似文献
7.
8.
9.
10.
M.A. Tawhid 《Journal of Optimization Theory and Applications》2002,113(1):149-164
In this paper, we give some sufficient conditions for the local uniqueness of solutions to nonsmooth variational inequalities where the underlying functions are H-differentiable and the underlying set is a closed convex set/polyhedral set/box/polyhedral cone. We show how the solution of a linearized variational inequality is related to the solution of the variational inequality. These results extend/unify various similar results proved for C
1 and locally Lipschitzian variational inequality problems. When specialized to the nonlinear complementarity problem, our results extend/unify those of C
2 and C
1 nonlinear complementarity problems. 相似文献