全文获取类型
收费全文 | 1612427篇 |
免费 | 44342篇 |
国内免费 | 17771篇 |
专业分类
化学 | 710381篇 |
晶体学 | 20831篇 |
力学 | 78894篇 |
综合类 | 420篇 |
数学 | 249487篇 |
物理学 | 395905篇 |
无线电 | 218622篇 |
出版年
2021年 | 17870篇 |
2020年 | 20256篇 |
2019年 | 20448篇 |
2018年 | 16233篇 |
2017年 | 14298篇 |
2016年 | 33118篇 |
2015年 | 25371篇 |
2014年 | 37167篇 |
2013年 | 84387篇 |
2012年 | 47282篇 |
2011年 | 44582篇 |
2010年 | 45042篇 |
2009年 | 49842篇 |
2008年 | 45818篇 |
2007年 | 42398篇 |
2006年 | 48224篇 |
2005年 | 40066篇 |
2004年 | 40078篇 |
2003年 | 37492篇 |
2002年 | 38269篇 |
2001年 | 37625篇 |
2000年 | 33512篇 |
1999年 | 30953篇 |
1998年 | 29160篇 |
1997年 | 28962篇 |
1996年 | 28408篇 |
1995年 | 25939篇 |
1994年 | 25269篇 |
1993年 | 24367篇 |
1992年 | 24206篇 |
1991年 | 24284篇 |
1990年 | 22950篇 |
1989年 | 22387篇 |
1988年 | 21519篇 |
1987年 | 20264篇 |
1986年 | 19019篇 |
1985年 | 25467篇 |
1984年 | 26616篇 |
1983年 | 22420篇 |
1982年 | 23805篇 |
1981年 | 22963篇 |
1980年 | 22228篇 |
1979年 | 22167篇 |
1978年 | 23385篇 |
1977年 | 22970篇 |
1976年 | 22541篇 |
1975年 | 21187篇 |
1974年 | 20823篇 |
1973年 | 21277篇 |
1972年 | 15479篇 |
排序方式: 共有10000条查询结果,搜索用时 484 毫秒
121.
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
122.
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
123.
124.
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
125.
Numerical Algorithms - In this paper, the block generalized product-type bi-conjugate gradient (GPBi-CG) method for solving large, sparse nonsymmetric linear systems of equations with multiple... 相似文献
126.
Mobile Networks and Applications - Blockchain applications have continuously improved ever since its first debut on cryptocurrency. From then on, its uses have branched out from the financial... 相似文献
127.
Shuhai Liu Ming Han Xiaolong Feng Qiuhong Yu Long Gu Longfei Wang Yong Qin Zhong Lin Wang 《Advanced functional materials》2021,31(17):2010339
Utilizing inner-crystal piezoelectric polarization charges to control carrier transport across a metal-semiconductor or semiconductor–semiconductor interface, piezotronic effect has great potential applications in smart micro/nano-electromechanical system (MEMS/NEMS), human-machine interfacing, and nanorobotics. However, current research on piezotronics has mainly focused on systems with only one or rather limited interfaces. Here, the statistical piezotronic effect is reported in ZnO bulk composited of nanoplatelets, of which the strain/stress-induced piezo-potential at the crystals’ interfaces can effectively gate the electrical transport of ZnO bulk. It is a statistical phenomenon of piezotronic modification of large numbers of interfaces, and the crystal orientation of inner ZnO nanoplatelets strongly influence the transport property of ZnO bulk. With optimum preferred orientation of ZnO nanoplatelets, the bulk exhibits an increased conductivity with decreasing stress at a high pressure range of 200–400 MPa, which has not been observed previously in bulk. A maximum sensitivity of 1.149 µS m−1 MPa−1 and a corresponding gauge factor of 467–589 have been achieved. As a statistical phenomenon of many piezotronic interfaces modulation, the proposed statistical piezotronic effect extends the connotation of piezotronics and promotes its practical applications in intelligent sensing. 相似文献
128.
Matteo Di Giosia Alice Soldà Markus Seeger Andrea Cantelli Fabio Arnesano Maria I. Nardella Vincenzo Mangini Francesco Valle Marco Montalti Francesco Zerbetto Stefania Rapino Matteo Calvaresi Vasilis Ntziachristos 《Advanced functional materials》2021,31(20):2101527
Fullerenes are candidates for theranostic applications because of their high photodynamic activity and intrinsic multimodal imaging contrast. However, fullerenes suffer from low solubility in aqueous media, poor biocompatibility, cell toxicity, and a tendency to aggregate. C70@lysozyme is introduced herein as a novel bioconjugate that is harmless to a cellular environment, yet is also photoactive and has excellent optical and optoacoustic contrast for tracking cellular uptake and intracellular localization. The formation, water-solubility, photoactivity, and unperturbed structure of C70@lysozyme are confirmed using UV-visible and 2D 1H, 15N NMR spectroscopy. The excellent imaging contrast of C70@lysozyme in optoacoustic and third harmonic generation microscopy is exploited to monitor its uptake in HeLa cells and lysosomal trafficking. Last, the photoactivity of C70@lysozyme and its ability to initiate cell death by means of singlet oxygen (1O2) production upon exposure to low levels of white light irradiation is demonstrated. This study introduces C70@lysozyme and other fullerene-protein conjugates as potential candidates for theranostic applications. 相似文献
129.
Mathematical Notes - 相似文献
130.
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