全文获取类型
收费全文 | 146389篇 |
免费 | 8745篇 |
国内免费 | 6316篇 |
专业分类
化学 | 56469篇 |
晶体学 | 1294篇 |
力学 | 8980篇 |
综合类 | 299篇 |
数学 | 36989篇 |
物理学 | 31078篇 |
无线电 | 26341篇 |
出版年
2024年 | 216篇 |
2023年 | 1278篇 |
2022年 | 1695篇 |
2021年 | 2145篇 |
2020年 | 2030篇 |
2019年 | 2016篇 |
2018年 | 13260篇 |
2017年 | 12810篇 |
2016年 | 9187篇 |
2015年 | 3414篇 |
2014年 | 3451篇 |
2013年 | 4401篇 |
2012年 | 8908篇 |
2011年 | 16357篇 |
2010年 | 10304篇 |
2009年 | 10207篇 |
2008年 | 10966篇 |
2007年 | 13123篇 |
2006年 | 3597篇 |
2005年 | 4450篇 |
2004年 | 3950篇 |
2003年 | 3928篇 |
2002年 | 2810篇 |
2001年 | 1697篇 |
2000年 | 1565篇 |
1999年 | 1496篇 |
1998年 | 1289篇 |
1997年 | 1163篇 |
1996年 | 1226篇 |
1995年 | 986篇 |
1994年 | 868篇 |
1993年 | 820篇 |
1992年 | 687篇 |
1991年 | 631篇 |
1990年 | 517篇 |
1989年 | 412篇 |
1988年 | 370篇 |
1987年 | 274篇 |
1986年 | 295篇 |
1985年 | 284篇 |
1984年 | 221篇 |
1983年 | 142篇 |
1982年 | 157篇 |
1981年 | 122篇 |
1980年 | 131篇 |
1979年 | 117篇 |
1978年 | 96篇 |
1976年 | 78篇 |
1974年 | 72篇 |
1973年 | 88篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
2.
Lin Yu Wu Yeyu Tan Xuecai Wu Jiawen Huang Kejing Mi Yan Ou Panpan Wei Fucun 《Journal of Solid State Electrochemistry》2022,26(4):959-971
Journal of Solid State Electrochemistry - An ultrasensitive “signal-off–on” electrochemiluminescence (ECL) biosensor is constructed based on f1-TiO2/g-C3N4/PDA for thrombin... 相似文献
3.
Mathematical Programming - We provide a control-theoretic perspective on optimal tensor algorithms for minimizing a convex function in a finite-dimensional Euclidean space. Given a function... 相似文献
4.
Shilin Jiang Dr. Yalan Liu Dr. Lin Wang Prof. Zhifang Chai Prof. Wei-Qun Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(60):e202201145
The coordination chemistry of f-block elements (lanthanide and actinide) in molten salts has become a resounding topic in view of its great importance to the research and development (R&D) of molten salt reactors and pyroprocessing. In this Review article, a general overview of the coordination chemistry of f-block elements in molten salts is provided including past achievements and recent advances. Particular emphases are placed on the oxidation state, speciation, and solution structure of f-block metal ions in molten salts, as well as their relationships with the salt composition. Furthermore, this review briefly discusses the spectroscopic and theoretical methods that complement each other in revealing the coordination properties. 相似文献
5.
6.
7.
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
8.
Journal of Signal Processing Systems - With the latest development of automation technology, object detection technology has received more and more research attention. Automated object detection... 相似文献
9.
Nonlinear Dynamics - This paper proposes an optimal parameter design of control scheme for mechanical systems by adopting the Stackelberg game theory. The goal of the control is to drive the... 相似文献
10.
Yan He Kangren Kong Zhengxi Guo Weifeng Fang Zaiqiang Ma Haihua Pan Ruikang Tang Zhaoming Liu 《Advanced functional materials》2021,31(26):2101291
Sensitivity and multi-directional motivation are major two factors for developing optimized humidity-response materials, which are promising for sensing, energy production, etc. Organic functional groups are commonly used as the water sensitive units through hydrogen bond interactions with water molecules in actuators. The multi-coordination ability of inorganic ions implies that the inorganic ionic compounds are potentially superior water sensitive units. However, the particle forms of inorganic ionic compounds produced by classical nucleation limit the number of exposed ions to interact with water. Recent progress on the inorganic ionic oligomers has broken through the limitation of classical nucleation, and realized the molecular-scaled incorporation of inorganic ionic compounds into an organic matrix. Here, the incorporation of hydrophilic calcium carbonate ionic oligomers into hydrophobic poly(vinylidene fluoride) (PVDF) is demonstrated. The ultra-small calcium carbonate oligomers within a PVDF film endow it with an ultra-sensitive, reversible, and bidirectional response. The motivation ability is superior to other bidirectional humidity-actuators at present, which realizes self-motivation on an ice surface, converting the chemical potential energy of the humidity gradient from ice to kinetic energy. 相似文献