全文获取类型
收费全文 | 8201篇 |
免费 | 112篇 |
国内免费 | 39篇 |
专业分类
化学 | 4903篇 |
晶体学 | 76篇 |
力学 | 327篇 |
数学 | 1226篇 |
物理学 | 1820篇 |
出版年
2022年 | 112篇 |
2021年 | 137篇 |
2020年 | 174篇 |
2019年 | 183篇 |
2018年 | 189篇 |
2017年 | 201篇 |
2016年 | 262篇 |
2015年 | 123篇 |
2014年 | 205篇 |
2013年 | 397篇 |
2012年 | 342篇 |
2011年 | 388篇 |
2010年 | 296篇 |
2009年 | 290篇 |
2008年 | 327篇 |
2007年 | 320篇 |
2006年 | 256篇 |
2005年 | 218篇 |
2004年 | 228篇 |
2003年 | 201篇 |
2002年 | 227篇 |
2001年 | 136篇 |
2000年 | 118篇 |
1999年 | 80篇 |
1998年 | 86篇 |
1997年 | 79篇 |
1995年 | 108篇 |
1994年 | 115篇 |
1993年 | 98篇 |
1992年 | 73篇 |
1991年 | 107篇 |
1990年 | 98篇 |
1989年 | 101篇 |
1988年 | 72篇 |
1987年 | 86篇 |
1986年 | 75篇 |
1985年 | 101篇 |
1984年 | 134篇 |
1983年 | 84篇 |
1982年 | 103篇 |
1981年 | 81篇 |
1980年 | 86篇 |
1979年 | 125篇 |
1978年 | 120篇 |
1977年 | 113篇 |
1976年 | 122篇 |
1975年 | 98篇 |
1974年 | 70篇 |
1973年 | 96篇 |
1970年 | 71篇 |
排序方式: 共有8352条查询结果,搜索用时 15 毫秒
91.
V. A. Aleksandrov A. S. Sabirov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2016,10(6):1266-1269
The channeling of hydrogen atoms in bundles of carbon nanotubes in the presence of vacancies on walls and adsorbed atoms inside the tubes is studied by means of computer simulation. A change in the parameters of the beam of channeling particles during interaction with the indicated defects makes it possible to detect the structural damage of nanotube bundles. 相似文献
92.
N. A. Gundorin Sh. S. Zeinalov Yu. N. Kopach A. B. Popov V. I. Furman 《Physics of Particles and Nuclei》2016,47(4):681-701
We review the experimental results on the P-even and P-odd angular correlations of fission fragments in the fission of the 235U and 239Pu nuclei induced by unpolarized and polarized resonance neutrons, and on the TRI and ROT effects in the ternary and binary fission of actinides induced by polarized thermal neutrons. Also reported are the measured yields of prompt and delayed neutrons per fission event. The experimental data are analyzed within a novel theoretical framework developed by the JINR—RNC KI Collaboration, whereby the reduction of the multidimensional phase space of fission fragments to the JπK-channel space is consistently validated and the role of resonance interference in the observed correlation effects is revealed. 相似文献
93.
S. Sh. Rekhviashvili Murat O. Mamchuev Mukhtar O. Mamchuev 《Physics of the Solid State》2016,58(4):788-791
A new theoretical (semiempirical) model of diffusion-drift charge carrier transport in layers with a fractal structure based on a partial differential equation with a fractional time derivative has been proposed. It has been shown by numerical calculations that a decrease in the order of the fractional derivative in the presence of the external electric field leads to broadening and asymmetry of the spatial distributions of charge carriers, which physically corresponds to intensification of scattering processes. 相似文献
94.
V. Grebenyuk V. Boreiko A. Dmitrotsa N. Gorbunov B. Khrenov P. Klimov M. Lavrova E. M. Popescu B. Sabirov A. Tkachenko L. Tkachev A. Volvach I. Yashin 《Physics of Particles and Nuclei Letters》2016,13(5):579-582
The purpose TUS space experiment is to study cosmic rays of ultrahigh energies produced by extensive air showers from space. The concentrator is located on satellite, made in the form of the Fresnel mirror towards the earth’s atmosphere, the focus of which is a photodetector. The angle of view of the mirror is ±4.5° that for a given height of the orbit corresponds to the area 80 × 80 km2 on ground. The ground complex consisting of a number of stations, to check the optical system of the experiment is created, (their location and the amount will be determined after the launch of the satellite based on its actual orbit). 相似文献
95.
96.
Pavel M. Bleher Denis V. Kosygin Yakov G. Sinai 《Communications in Mathematical Physics》1995,170(2):375-403
We consider the Weyl asymptotic formula
相似文献
97.
Philippe Pinel Bertrand Thirion Sébastien Meriaux Antoinette Jobert Julien Serres Denis Le Bihan Jean-Baptiste Poline Stanislas Dehaene 《BMC neuroscience》2007,8(1):91
BackgroundAlthough cognitive processes such as reading and calculation are associated with reproducible cerebral networks, inter-individual variability is considerable. Understanding the origins of this variability will require the elaboration of large multimodal databases compiling behavioral, anatomical, genetic and functional neuroimaging data over hundreds of subjects. With this goal in mind, we designed a simple and fast acquisition procedure based on a 5-minute functional magnetic resonance imaging (fMRI) sequence that can be run as easily and as systematically as an anatomical scan, and is therefore used in every subject undergoing fMRI in our laboratory. This protocol captures the cerebral bases of auditory and visual perception, motor actions, reading, language comprehension and mental calculation at an individual level. 相似文献98.
A. A. Afanas'ev V. M. Katarkevich A. N. Rubinov T. Sh. Éfendiev 《Journal of Applied Spectroscopy》2002,69(5):782-787
Spatial redistribution of microparticles in a suspension on exposure to the interference laser field depending on the parameters of the particles and the field characteristics has been analyzed theoretically. Results of experimental investigations are presented that illustrate the capture of an ensemble of polymeric small spheres and also of the lymphocytes of human blood and other microparticles in a liquid in the interference radiation bands of the He–Ne laser. 相似文献
99.
100.
|