全文获取类型
收费全文 | 220952篇 |
免费 | 5062篇 |
国内免费 | 2665篇 |
专业分类
化学 | 114874篇 |
晶体学 | 3521篇 |
力学 | 10299篇 |
综合类 | 108篇 |
数学 | 24275篇 |
物理学 | 75602篇 |
出版年
2022年 | 1764篇 |
2021年 | 2297篇 |
2020年 | 2526篇 |
2019年 | 2704篇 |
2018年 | 3322篇 |
2017年 | 3162篇 |
2016年 | 4606篇 |
2015年 | 3115篇 |
2014年 | 4598篇 |
2013年 | 10341篇 |
2012年 | 8782篇 |
2011年 | 10203篇 |
2010年 | 7066篇 |
2009年 | 6874篇 |
2008年 | 8966篇 |
2007年 | 9070篇 |
2006年 | 8624篇 |
2005年 | 7714篇 |
2004年 | 7014篇 |
2003年 | 6153篇 |
2002年 | 5978篇 |
2001年 | 6795篇 |
2000年 | 5277篇 |
1999年 | 4211篇 |
1998年 | 3376篇 |
1997年 | 3377篇 |
1996年 | 3104篇 |
1995年 | 2888篇 |
1994年 | 2683篇 |
1993年 | 2535篇 |
1992年 | 2844篇 |
1991年 | 2802篇 |
1990年 | 2755篇 |
1989年 | 2502篇 |
1988年 | 2522篇 |
1987年 | 2501篇 |
1986年 | 2337篇 |
1985年 | 3015篇 |
1984年 | 3243篇 |
1983年 | 2659篇 |
1982年 | 2825篇 |
1981年 | 2788篇 |
1980年 | 2646篇 |
1979年 | 2729篇 |
1978年 | 2821篇 |
1977年 | 2822篇 |
1976年 | 2886篇 |
1975年 | 2670篇 |
1974年 | 2644篇 |
1973年 | 2777篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
S. D. Campos 《中国物理C(英文版)》2020,44(10):103103-103103-10
This work presents the subtraction procedure and the Regge cut in the logarithmic Regge pole approach. The subtraction mechanism leads to the same asymptotic behavior as previously obtained in the non-subtraction case. The Regge cut, in contrast, introduces a clear role to the non-leading contributions for the asymptotic behavior of the total cross-section. From these results, some simple parameterization is introduced to fit the experimental data for the proton-proton and antiproton-proton total cross-section above some minimum value up to the cosmic-ray. The fit parameters obtained are used to present predictions for the \begin{document}$ \rho(s)$\end{document}
-parameter as well as to the elastic slope \begin{document}$ B(s)$\end{document}
at high energies. 相似文献
63.
Hui Li Jian Liu Juan Zhao Huiting He Dr. Dabo Jiang Prof. Steven Robert Kirk Prof. Qiong Xu Dr. Xianxiang Liu Prof. Dulin Yin 《ChemistryOpen》2021,10(4):477-485
A series of tetraimidazolium salts with different anions was prepared and applied in the isomerization of β-pinene oxide. After examining the activity of different catalysts, a remarkable enhancement of the selectivity of perillyl alcohol (47 %) was obtained over [PEimi][HNO3]4 under mild reaction conditions and using DMSO as the solvent. Furthermore, noncovalent interactions between solvent molecules and the catalyst were found by FT-IR spectroscopy and confirmed by computational chemistry. The homogeneous catalyst showed excellent stability and was reused up to six times without significant loss. 相似文献
64.
Mathematical Notes - We study the multiplicity of weak solutions to the boundary-value problem $$\begin{alignedat}{2} - M\biggl(\iint_{\mathbb R^{2N}}|u(x)-u(y)|^2 K(x-y)\,d x\,d y\biggr)\mathscr... 相似文献
65.
Optics and Spectroscopy - A cell with a submicron thickness was used to measure the broadening and shift of the D1 and D2 lines of Rb atoms by neon. The resolution of hypefine components... 相似文献
66.
67.
Periodica Mathematica Hungarica - We present a tight parametrical Hermite–Hadamard type inequality with probability measure, which yields a considerably closer upper bound for the mean value... 相似文献
68.
Mathematical Notes - It is proved that the lattice of all Fitting classes of finite groups is not distributive, and conditions under which Fitting classes satisfy the distributive and modular laws... 相似文献
69.
Kuzmenkova P. S. Gromushkin D. M. Shulzhenko I. A. Tretyakova T. D. 《Physics of Atomic Nuclei》2021,84(9):1588-1592
Physics of Atomic Nuclei - The paper presents a comparison of three neutrons identifying methods in scintillators based on ZnS with 6Li and 10B: charge integration method, pulse gradient analysis,... 相似文献
70.
Ding Q. Yao M. Wu Sh. Zeng M. Xue N. Wu D. Xu J. 《Journal of Applied Spectroscopy》2022,89(4):712-718
Journal of Applied Spectroscopy - Based on partial least squares (PLS) analysis, the effects of different smoothing points and different preprocessing methods on the accuracy and precision of the... 相似文献