全文获取类型
收费全文 | 58830篇 |
免费 | 857篇 |
国内免费 | 292篇 |
专业分类
化学 | 27362篇 |
晶体学 | 955篇 |
力学 | 3197篇 |
综合类 | 8篇 |
数学 | 4676篇 |
物理学 | 23781篇 |
出版年
2022年 | 424篇 |
2021年 | 472篇 |
2020年 | 451篇 |
2019年 | 435篇 |
2018年 | 577篇 |
2017年 | 501篇 |
2016年 | 896篇 |
2015年 | 640篇 |
2014年 | 998篇 |
2013年 | 2510篇 |
2012年 | 2348篇 |
2011年 | 3047篇 |
2010年 | 2139篇 |
2009年 | 2184篇 |
2008年 | 2762篇 |
2007年 | 2604篇 |
2006年 | 2460篇 |
2005年 | 2183篇 |
2004年 | 2003篇 |
2003年 | 1767篇 |
2002年 | 1656篇 |
2001年 | 3013篇 |
2000年 | 2154篇 |
1999年 | 1563篇 |
1998年 | 1085篇 |
1997年 | 1060篇 |
1996年 | 890篇 |
1995年 | 768篇 |
1994年 | 698篇 |
1993年 | 610篇 |
1992年 | 939篇 |
1991年 | 926篇 |
1990年 | 836篇 |
1989年 | 736篇 |
1988年 | 730篇 |
1987年 | 791篇 |
1986年 | 648篇 |
1985年 | 874篇 |
1984年 | 819篇 |
1983年 | 560篇 |
1982年 | 564篇 |
1981年 | 534篇 |
1980年 | 496篇 |
1979年 | 617篇 |
1978年 | 645篇 |
1977年 | 659篇 |
1976年 | 574篇 |
1975年 | 483篇 |
1974年 | 522篇 |
1973年 | 448篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
1.
Mazurenko V. V. Kvashnin Y. O. Lichtenstein A. I. Katsnelson M. I. 《Journal of Experimental and Theoretical Physics》2021,132(4):506-516
Journal of Experimental and Theoretical Physics - Dzyaloshinskii–Moriya interaction, DMI in short, represents an antisymmetric type of magnetic interactions that favor orthogonal orientation... 相似文献
2.
3.
Kinetics and Catalysis - The catalytic properties of a nickel phosphide catalyst supported on silica gel in the reductive amination of carbonyl compounds were studied in a flow reactor using... 相似文献
4.
Yang T. L. Kao C. L. Kuo C. E. Yeh H. C. Li W. J. Li H. T. Chen C. Y. 《Chemistry of Natural Compounds》2022,58(5):825-827
Chemistry of Natural Compounds - A novel bibenzyl derivative, hydrangchinenin (1), was isolated from the stems of Hydrangea chinensis Maxim. (Hydrangeaceae). Its structure was determined on the... 相似文献
5.
Kento Nishikibe Keisuke Nishikawa Momochika Kumagai Matsumi Doe Yoshiki Morimoto 《化学:亚洲杂志》2022,17(1):e202101137
There are marine cytotoxic bromotriterpenoids, named the thyrsiferol family that are structurally characterized by some tetrahydropyran (THP) and tetrahydrofuran (THF) rings. The thyrsiferol family belongs to natural products that are often difficult to determine their stereostructures even by the current, highly advanced spectroscopic methods, especially in acyclic systems including stereogenic tetrasubstituted carbon centers. In such cases, it is effective to predict and synthesize the possible stereostructures. Herein, to elucidate ambiguous stereostructures and unassigned absolute configurations of aplysiol B, laurenmariannol, and saiyacenol A, members of the thyrsiferol family, we carried out their asymmetric chemical syntheses featuring 6-exo and 5-exo oxacyclizations of epoxy alcohol precursors and 6-endo bromoetherification of a bishomoallylic alcohol. In this paper, we report total assignments of their stereostructures through their asymmetric chemical syntheses and also their preliminary cytotoxic activities against some tumor cells. These results could not have been achieved without depending on asymmetric total synthesis. 相似文献
6.
Kacher Y. G. Karlova M. G. Glukhov G. S. Zhang H. Zaklyazminskaya E. V. Loussouarn G. Sokolova O. S. 《Crystallography Reports》2021,66(5):711-725
Crystallography Reports - Membrane proteins, including ion channels, became the focus of structural proteomics midway through the 20th century. Methods for studying ion channels are diverse and... 相似文献
7.
Kobayashi M. Zhang Y. Ishikawa H. Sun J. Oddershede J. Juul Jensen D. Miura H. 《Experimental Mechanics》2021,61(5):817-828
Experimental Mechanics - The internal strain distribution developing during plastic deformation is important for understanding the mechanical properties of polycrystalline materials. Such... 相似文献
8.
Lebedev D. V. Egorov V. V. Shvetsov A. V. Zabrodskaya Y. A. Isaev-Ivanov V. V. Konevega A. L. 《Crystallography Reports》2021,66(2):242-253
Crystallography Reports - The review describes the application of small-angle scattering (SAS) of neutrons and complementary methods to study the structures of biomacromolecules. Here we cover SAS... 相似文献
9.
10.
Li Y. Shi W. H. Dong L. M. Xu S. X. Huang H. J. Yin J. R. 《Journal of Applied Spectroscopy》2022,89(3):534-541
Journal of Applied Spectroscopy - Sr3B2O6:Dy3+, Eu3+ single-matrix white-light-emitting materials are prepared using the high-temperature solid-state method. The microstructure, emission spectrum,... 相似文献