全文获取类型
收费全文 | 362973篇 |
免费 | 2936篇 |
国内免费 | 840篇 |
专业分类
化学 | 192096篇 |
晶体学 | 5761篇 |
力学 | 16852篇 |
综合类 | 11篇 |
数学 | 38763篇 |
物理学 | 113266篇 |
出版年
2018年 | 4569篇 |
2017年 | 4621篇 |
2016年 | 6270篇 |
2015年 | 3454篇 |
2014年 | 5850篇 |
2013年 | 14435篇 |
2012年 | 10430篇 |
2011年 | 12717篇 |
2010年 | 9651篇 |
2009年 | 9699篇 |
2008年 | 11894篇 |
2007年 | 11960篇 |
2006年 | 11072篇 |
2005年 | 9906篇 |
2004年 | 9373篇 |
2003年 | 8418篇 |
2002年 | 8504篇 |
2001年 | 10294篇 |
2000年 | 7770篇 |
1999年 | 6071篇 |
1998年 | 5146篇 |
1997年 | 5032篇 |
1996年 | 4818篇 |
1995年 | 4414篇 |
1994年 | 4284篇 |
1993年 | 4202篇 |
1992年 | 4680篇 |
1991年 | 4873篇 |
1990年 | 4794篇 |
1989年 | 4870篇 |
1988年 | 4721篇 |
1987年 | 4757篇 |
1986年 | 4389篇 |
1985年 | 5755篇 |
1984年 | 5803篇 |
1983年 | 4924篇 |
1982年 | 5155篇 |
1981年 | 5010篇 |
1980年 | 4715篇 |
1979年 | 5162篇 |
1978年 | 5567篇 |
1977年 | 5498篇 |
1976年 | 5507篇 |
1975年 | 5174篇 |
1974年 | 5088篇 |
1973年 | 5267篇 |
1972年 | 3872篇 |
1971年 | 3396篇 |
1968年 | 3546篇 |
1967年 | 3725篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Varfolomeev S. D. Panin A. A. Semenova N. A. Ublinskiy M. V. Akhadov T. A. Bykov V. I. Tsybenova S. B. 《Russian Chemical Bulletin》2022,71(3):591-594
A kinetic study of the effect of thermoheliox (inhalation of a helium and oxygen mixture, 70 °C) on the functional hemodynamics of the human brain by functional magnetic resonance imaging was carried out. The dynamic responses of the BOLD signal were found to be biphasic. An empirical equation describing the first phase of the hemodynamic response to visual stimulus was proposed. It was shown that preliminary inhalation of thermoheliox stimulates the hemodynamic responses by slowing down the vasoconstriction.
相似文献22.
Edward G. Sheetz Zhao Zhang Alyssa Marogil Minwei Che Dr. Maren Pink Dr. Veronica Carta Prof. Dr. Krishnan Raghavachari Prof. Dr. Amar H. Flood 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(60):e202201584
The recognition of boron compounds is well developed as boronic acids but untapped as organotrifluoroborate anions (R−BF3−). We are exploring the development of these and other designer anions as anion-recognition motifs by considering them as substituted versions of the parent inorganic ion. To this end, we demonstrate strong and reliable binding of organic trifluoroborates, R−BF3−, by cyanostar macrocycles that are size-complementary to the inorganic BF4− progenitors. We find that recognition is modulated by the substituent's sterics and that the affinities are retained using the common K+ salts of R−BF3− anions. 相似文献
23.
Experimental Mechanics - Temperature gradients significantly affect the material fatigue process. A reliable and robust test procedure is needed for quantifying the effects of temperature gradients... 相似文献
24.
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
25.
JETP Letters - Extraordinary multiparticle effects in quantizing magnetic fields that are manifested in strongly interacting two-dimensional electron systems in MgZnO/ZnO heterostructures have been... 相似文献
26.
Alawainati F. A. Manaa H. Henari F. Z. Biyiklioglu Z. Arslan T. Jaafar A. 《Journal of Applied Spectroscopy》2021,88(5):951-957
Journal of Applied Spectroscopy - Detailed measurements of nonlinear optical properties and optical limiting for four phthalocyanine (Pc) derivatives (PcCo, PcCu, PcMn, and PcSi) are reported. The... 相似文献
27.
Zadeba E. A. Khokhlov S. S. Kokoulin R. P. Petrukhin A. A. Shulzhenko I. A. Yashin I. I. 《Physics of Atomic Nuclei》2022,85(1):86-91
Physics of Atomic Nuclei - The muon puzzle is an excess of muon bundles generated by primary cosmic rays (PCR) at energies above 10 $${}^{17}$$ eV compared to estimations that assume even a heavy... 相似文献
28.
Kopytov G. F. Malyshko V. V. Goryachko A. I. Sharafan M. V. Churkina A. V. Moiseev A. V. Shashkov D. I. Lyasota O. M. 《Russian Physics Journal》2021,64(2):255-260
Russian Physics Journal - The specific features of the sorption activity of silver nanoparticles (AgNPs) on biodegradable polymers of natural (collagen) and artificial (polyamide 6.6) origin have... 相似文献
29.
Kuz’mina L. G. Navasardyan M. A. Kalle P. Bezzubov S. I. 《Crystallography Reports》2021,66(3):420-423
Crystallography Reports - The crystal and molecular structures of Cl–C6H4–O–C16H33 (I) have been studied, and its differential scanning calorimetry (DSC) study is performed.... 相似文献
30.