全文获取类型
收费全文 | 239991篇 |
免费 | 2017篇 |
国内免费 | 673篇 |
专业分类
化学 | 117927篇 |
晶体学 | 3270篇 |
力学 | 8349篇 |
综合类 | 6篇 |
数学 | 23307篇 |
物理学 | 64777篇 |
无线电 | 25045篇 |
出版年
2020年 | 2203篇 |
2019年 | 2521篇 |
2018年 | 3492篇 |
2017年 | 3351篇 |
2016年 | 4585篇 |
2015年 | 2531篇 |
2014年 | 4147篇 |
2013年 | 9799篇 |
2012年 | 7285篇 |
2011年 | 8908篇 |
2010年 | 6559篇 |
2009年 | 6683篇 |
2008年 | 9012篇 |
2007年 | 9274篇 |
2006年 | 8697篇 |
2005年 | 7908篇 |
2004年 | 7133篇 |
2003年 | 6576篇 |
2002年 | 6457篇 |
2001年 | 6843篇 |
2000年 | 5664篇 |
1999年 | 4299篇 |
1998年 | 3848篇 |
1997年 | 3786篇 |
1996年 | 3533篇 |
1995年 | 3010篇 |
1994年 | 3127篇 |
1993年 | 3082篇 |
1992年 | 3210篇 |
1991年 | 3306篇 |
1990年 | 3189篇 |
1989年 | 3082篇 |
1988年 | 2958篇 |
1987年 | 2683篇 |
1986年 | 2609篇 |
1985年 | 3297篇 |
1984年 | 3434篇 |
1983年 | 2778篇 |
1982年 | 3024篇 |
1981年 | 2866篇 |
1980年 | 2690篇 |
1979年 | 2880篇 |
1978年 | 2976篇 |
1977年 | 2998篇 |
1976年 | 2959篇 |
1975年 | 2814篇 |
1974年 | 2797篇 |
1973年 | 2929篇 |
1972年 | 1997篇 |
1967年 | 1902篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Galkina E. G. Zaspel C. E. Ivanov B. A. Kulagin N. E. Lerman L. M. 《JETP Letters》2019,110(7):481-486
JETP Letters - The motion of domain walls in GdFeCo-type ferrimagnets near the point of compensation of sublattice spins s1 and s2, when the effects of the exchange increase in the limiting wall... 相似文献
32.
K.M.J. Rocha R.G. Leitão E.G. Oliveira-Barros M.A. Oliveira C.G.L. Canellas M.J. Anjos L.E. Nasciutti R.T. Lopes 《X射线光谱测定》2019,48(5):476-481
Prostate cancer is a highly prevalent disease and ranks second among malignant neoplasms that affect men around the world, behind lung cancer alone. Trace elements are very important and are involved in many cellular processes. The X-ray microfluorescence technique is an advanced tool of high spatial resolution, sensitivity, multielemental analysis, and nondestructiveness for trace element study. This study aimed to investigate the elemental distribution in spheroids obtained through the following human prostate cell lines using synchrotron X-ray microfluorescence: tumor cell line androgen independent (DU145), tumor cell line androgen dependent (LNCaP), and normal cell line (RWPE-1). The measurements were performed with a standard geometry of 45° of incidence, excited by a white beam using a pixel of 25 μm and an acquisition time of 300 ms/pixel at the X-ray fluorescence beamline at the Synchrotron Light National Laboratory (Campinas, Brazil). The synchrotron X-ray microfluorescence results showed differences between groups in all elements analyzed and suggested that further studies should be performed to understand the relationship of these trace elements with the progression and development of the disease. 相似文献
33.
34.
Ivanov K. A. Gubaidullin A. R. Morozov K. M. Sasin M. E. Kaliteevskii M. A. 《Optics and Spectroscopy》2019,126(6):787-787
Optics and Spectroscopy - 10.1134/S0030400X17050095 相似文献
35.
Kaplunov I. A. Kolesnikov A. I. Kropotov G. I. Rogalin V. E. 《Optics and Spectroscopy》2019,126(3):191-194
Optics and Spectroscopy - The transmission of intrinsic, antimony-doped, and gallium-doped Ge single crystals in the THz spectral range have been experimentally investigated. It is shown that the... 相似文献
36.
37.
J. Conrad J. Cohen-Tanugi L. E. Strigari 《Journal of Experimental and Theoretical Physics》2015,121(6):1104-1135
The launch of the gamma-ray telescope Fermi Large Area Telescope (Fermi-LAT) started a pivotal period in indirect detection of dark matter. By outperforming expectations, for the first time a robust and stringent test of the paradigm of weakly interacting massive particles (WIMPs) is within reach. In this paper, we discuss astrophysical targets for WIMP detection and the challenges they present, review the analysis tools which have been employed to tackle these challenges, and summarize the status of constraints on and the claimed detections in the WIMP parameter space. Methods and results will be discussed in comparison to Imaging Air Cherenkov Telescopes. We also provide an outlook on short term and longer term developments. 相似文献
38.
39.
40.