全文获取类型
收费全文 | 1442篇 |
免费 | 70篇 |
国内免费 | 6篇 |
专业分类
化学 | 874篇 |
晶体学 | 15篇 |
力学 | 43篇 |
数学 | 373篇 |
物理学 | 213篇 |
出版年
2023年 | 16篇 |
2022年 | 65篇 |
2021年 | 67篇 |
2020年 | 62篇 |
2019年 | 68篇 |
2018年 | 78篇 |
2017年 | 57篇 |
2016年 | 90篇 |
2015年 | 71篇 |
2014年 | 81篇 |
2013年 | 104篇 |
2012年 | 121篇 |
2011年 | 99篇 |
2010年 | 65篇 |
2009年 | 51篇 |
2008年 | 58篇 |
2007年 | 41篇 |
2006年 | 43篇 |
2005年 | 43篇 |
2004年 | 32篇 |
2003年 | 22篇 |
2002年 | 15篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 7篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 10篇 |
1989年 | 4篇 |
1988年 | 9篇 |
1987年 | 4篇 |
1986年 | 8篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1980年 | 8篇 |
1979年 | 4篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1972年 | 5篇 |
1971年 | 3篇 |
排序方式: 共有1518条查询结果,搜索用时 10 毫秒
161.
Nguyen Thi Thu Huong Nguyen Chinh Cuong Ha Huy Bang Dao Thi Le Thuy 《International Journal of Theoretical Physics》2010,49(7):1457-1464
We study the pair production of scalar quark in a muon collider within the MSSM with CP violation. We show that including the CP phases can strongly affect the cross section of the process: \(\mu^{+}\mu^{-}\rightarrow \tilde{q}_{i}\bar{\tilde{q}}_{j}\). This could have an important impact on the search for squarks and the determination of the MSSM parameters at future colliders. 相似文献
162.
We have studied systematically room-temperature photoluminescence (PL) properties of many nanostructured ZnO samples grown by chemical vapour deposition (CVD). Their PL spectra consist of two emissions peaked in the ultraviolet (UV) and green regions. The relative intensity of these emissions depends on the excitation energy density, size and morphology of ZnO nanostructures. Based on the excitation-density dependence of the integrated intensity ratio of UV-to-green emission, we could classify PL spectra of ZnO nanostructures into three groups characteristic of size and morphology. Our study also reveals that with increasing excitation density, the UV-peak position shifts slightly towards longer wavelengths while the green emission around 514-520 nm is almost unchanged. This green-luminescence emission is dominant when the nanostructure sizes range from 20 to 200 nm, which is related to a large surface-to-volume ratio. 相似文献
163.
B.Z. Jiang T.L. Phan D.S. Yang K.W. Lee S.C. Yu 《Solid State Communications》2010,150(39-40):1932-1935
164.
165.
Weighted Calderón-Zygmund Estimates for Weak Solutions of Quasi-Linear Degenerate Elliptic Equations
Potential Analysis - This paper studies regularity estimates in Sobolev spaces for weak solutions of a class of degenerate and singular quasi-linear elliptic problems of the form... 相似文献
166.
Tuoc Phan & Yannick Sire 《分析论及其应用》2020,36(2):111-127
We establish local and global well-posedness of the 2D dissipative quasi-geostrophic equation in critical mixed norm Lebesgue spaces. The result demonstrates
the persistence of the anisotropic behavior of the initial data under the evolution of
the 2D dissipative quasi-geostrophic equation. The phenomenon is a priori nontrivial
due to the nonlocal structure of the equation. Our approach is based on Kato's method
using Picard's iteration, which can be adapted to the multi-dimensional case and
other nonlinear non-local equations. We develop time decay estimates for solutions of
fractional heat equation in mixed norm Lebesgue spaces that could be useful for other
problems. 相似文献
167.
The existence of exponential attractor for the diffusive Hindmarsh-Rose equations on a three-dimensional bounded domain in the study of neurodynamics is proved through uniform estimates and a new theorem on the squeezing property of the abstract reaction-diffusion equation established in this paper. This result on the exponential attractor infers that the global attractor whose existence has been proved in [22] for the diffusive Hindmarsh-Rose semiflow has a finite fractal dimension. 相似文献
168.
Global dynamics for a new mathematical model in neurodynamics of the diffusive Hindmarsh-Rose equations on a bounded domain is investigated in this paper. The existence of a global attractor and its regularity are proved through uniform estimates showing the dissipative properties and the asymptotically compact and smoothing characteristics. 相似文献
169.
Using elementary techniques, we prove a general transformation for theta series associated with the quadratic form \(x^2+ky^2.\) The transformation is then applied to establish several infinite families of identities involving theta series whose Fourier coefficients are interlinked. 相似文献
170.
We investigate the global exponential stability of equilibrium solutions of a projected dynamical system for variational inequalities. Under strong pseudomonotonicity and Lipschitz continuity assumptions, we prove that the dynamical system has a unique equilibrium solution. Moreover, this solution is globally exponentially stable. Some examples are given to analyze the effectiveness of the theoretical results. The numerical results confirm that the trajectory of the dynamical system globally exponentially converges to the unique solution of the considered variational inequality. The results established in this paper improve and extend some recent works. 相似文献