全文获取类型
收费全文 | 77689篇 |
免费 | 517篇 |
国内免费 | 112篇 |
专业分类
化学 | 41267篇 |
晶体学 | 1260篇 |
力学 | 3277篇 |
综合类 | 1篇 |
数学 | 7827篇 |
物理学 | 24686篇 |
出版年
2022年 | 631篇 |
2021年 | 871篇 |
2020年 | 965篇 |
2019年 | 1103篇 |
2018年 | 1596篇 |
2017年 | 1686篇 |
2016年 | 2148篇 |
2015年 | 1023篇 |
2014年 | 1719篇 |
2013年 | 3268篇 |
2012年 | 2896篇 |
2011年 | 3274篇 |
2010年 | 2636篇 |
2009年 | 2634篇 |
2008年 | 2997篇 |
2007年 | 2872篇 |
2006年 | 2767篇 |
2005年 | 2432篇 |
2004年 | 2237篇 |
2003年 | 2072篇 |
2002年 | 2133篇 |
2001年 | 2233篇 |
2000年 | 1623篇 |
1999年 | 1252篇 |
1998年 | 1125篇 |
1997年 | 1036篇 |
1996年 | 891篇 |
1995年 | 831篇 |
1994年 | 811篇 |
1993年 | 811篇 |
1992年 | 864篇 |
1991年 | 933篇 |
1990年 | 877篇 |
1989年 | 905篇 |
1988年 | 816篇 |
1987年 | 767篇 |
1986年 | 739篇 |
1985年 | 864篇 |
1984年 | 961篇 |
1983年 | 818篇 |
1982年 | 834篇 |
1981年 | 746篇 |
1980年 | 701篇 |
1979年 | 768篇 |
1978年 | 890篇 |
1977年 | 913篇 |
1976年 | 808篇 |
1975年 | 774篇 |
1974年 | 790篇 |
1973年 | 760篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
Journal of Experimental and Theoretical Physics - We suggest that the principle of holographic duality be extended beyond conformal invariance and AdS isometry. Such an extension is based on a... 相似文献
5.
6.
7.
In this work, the effect of various properties of materials on vacuum breakdown initiated by laser radiation is considered. Estimating calculations are performed which show that the material of the target electrode distinctly affects the minimum energy of laser radiation needed for igniting a vacuum spark. The experimental studies carried out confirm the estimating calculations, and a number of materials are revealed which can be arranged in order of increase in the energy needed for the formation of breakdown in vacuum by the impact of a laser pulse. 相似文献
8.
E. V. Shadrina O. N. Malinkina T. G. Khonina A. B. Shipovskaya V. I. Fomina E. Yu. Larchenko N. A. Popova I. G. Zyryanova L. P. Larionov 《Russian Chemical Bulletin》2015,64(7):1633-1639
The biomimetic sol—gel synthesis of silicon—chitosan-containing glycerohydrogels was carried out using silicon tetraglycerolate as a precursor. It was found that chitosan accelerates gel formation in weakly acidic media. In more acidic media, the kinetics of the process changes according to the curve with a maximum, which can be attributed to different mechanisms of silanol condensation before and after the isoelectric point. The investigated silicon—chitosan-containing glycerohydrogels exhibit antibacterial, anti-inflammatory, and wound healing activity. The synthesized hybrid glycerohydrogels are promising materials for biomedical applications. 相似文献
9.
S. V. Panin I. V. Vlasov V. P. Sergeev B. B. Ovechkin P. O. Marushchak Sunder Ramasubbu P. S. Lyubutin V. V. Titkov 《Physical Mesomechanics》2015,18(3):261-272
The structure and properties of 12Cr1MoV steel irradiated with a zirconium ion beam were studied by optical microscopy, scanning electron microscopy, and micro- and nanoindentation. It is shown that the modification covers the entire cross-section of the irradiated specimens to a depth of 1 mm. The data on irradiation-induced structural changes are used to interpret the changes in mechanical properties of the irradiated specimens under static and cyclic loading. Particular attention is given to analysis of strain estimation by the digital image correlation method. 相似文献
10.
Kondakov N. N. Mel´nikova T. M. Chekryzhova T. V. Mel´nikova M. V. Zinin A. I. Torgov V. I. Chizhov A. O. Kononov L. O. 《Russian Chemical Bulletin》2015,64(5):1142-1148
Russian Chemical Bulletin - Terminal disaccharide fragment of phenolic glycolipid from Mycobacterium leprae (PGL-I) was synthesized as a glycoside with 4-(2-aminoethoxy)phenyl aglycon. The obtained... 相似文献