全文获取类型
收费全文 | 4538篇 |
免费 | 147篇 |
国内免费 | 21篇 |
专业分类
化学 | 2812篇 |
晶体学 | 39篇 |
力学 | 79篇 |
数学 | 843篇 |
物理学 | 712篇 |
无线电 | 221篇 |
出版年
2023年 | 48篇 |
2022年 | 95篇 |
2021年 | 142篇 |
2020年 | 109篇 |
2019年 | 125篇 |
2018年 | 139篇 |
2017年 | 129篇 |
2016年 | 158篇 |
2015年 | 132篇 |
2014年 | 135篇 |
2013年 | 281篇 |
2012年 | 243篇 |
2011年 | 307篇 |
2010年 | 201篇 |
2009年 | 206篇 |
2008年 | 246篇 |
2007年 | 238篇 |
2006年 | 229篇 |
2005年 | 214篇 |
2004年 | 185篇 |
2003年 | 144篇 |
2002年 | 117篇 |
2001年 | 74篇 |
2000年 | 57篇 |
1999年 | 41篇 |
1998年 | 44篇 |
1997年 | 39篇 |
1996年 | 28篇 |
1995年 | 24篇 |
1994年 | 30篇 |
1993年 | 32篇 |
1992年 | 19篇 |
1991年 | 32篇 |
1990年 | 17篇 |
1989年 | 14篇 |
1987年 | 16篇 |
1986年 | 20篇 |
1985年 | 23篇 |
1984年 | 31篇 |
1983年 | 20篇 |
1982年 | 20篇 |
1981年 | 27篇 |
1980年 | 22篇 |
1979年 | 26篇 |
1978年 | 26篇 |
1977年 | 27篇 |
1975年 | 20篇 |
1974年 | 15篇 |
1958年 | 13篇 |
1955年 | 15篇 |
排序方式: 共有4706条查询结果,搜索用时 31 毫秒
991.
992.
Dr. Quan Pang Xiao Liang Ivan R. Kochetkov Dr. Pascal Hartmann Prof. Dr. Linda F. Nazar 《Angewandte Chemie (International ed. in English)》2018,57(31):9795-9798
The dendritic growth of Li metal leads to electrode degradation and safety concerns, impeding its application in building high energy density batteries. Forming a protective layer on the Li surface that is electron‐insulating, ion‐conducting, and maintains an intimate interface is critical. We herein demonstrate that Li plating is stabilized by a biphasic surface layer composed of a lithium‐indium alloy and a lithium halide, formed in situ by the reaction of an electrolyte additive with Li metal. This stabilization is attributed to the fast lithium migration though the alloy bulk and lithium halide surface, which is enabled by the electric field across the layer that is established owing to the electron‐insulating halide phase. A greatly stabilized Li‐electrolyte interface and dendrite‐free plating over 400 hours in Li|Li symmetric cells using an alkyl carbonate electrolyte is demonstrated. High energy efficiency operation of the Li4Ti5O12 (LTO)|Li cell over 1000 cycles is achieved. 相似文献
993.
Dr. Subrata Saha Dr. Brice Kauffmann Dr. Yann Ferrand Dr. Ivan Huc 《Angewandte Chemie (International ed. in English)》2018,57(41):13542-13546
Xylobiose sequestration in a helical aromatic oligoamide capsule was evidenced by circular dichroism, NMR spectroscopy, and crystallography. The preparation of the 5 kDa oligoamide sequence was made possible by the transient use of acid‐labile dimethoxybenzyl tertiary amide substituents that disrupt helical folding and prevent double helix formation. Binding of other disaccharides was not detected. Crystallographic data revealed a complex composed of a d ‐xylobiose α anomer and two water molecules accommodated in the right‐handed helix. The disaccharide was found to adopt an unusual all‐axial compact conformation. A dense network of 18 hydrogen bonds forms between the guest, the cavity wall, and the two water molecules. 相似文献
994.
995.
Ledeti Ionut Pusztai Agneta Maria Murariu Marius Olariu Sorin Ivan Codrut Circioban Denisa Vlase Gabriela Ledeti Adriana Vlase Titus Matusz Petru 《Journal of Thermal Analysis and Calorimetry》2018,131(2):1345-1360
Journal of Thermal Analysis and Calorimetry - In this work, solifenacin succinate (SOLS), flavoxate HCl (FLXHC) and tolterodine tartrate (TOLT) drugs were investigated using thermal analysis (TA)... 相似文献
996.
997.
Nourdin Ivan Peccati Giovanni Yang Xiaochuan 《Journal of Theoretical Probability》2022,35(3):2020-2037
Journal of Theoretical Probability - We establish explicit bounds on the convex distance between the distribution of a vector of smooth functionals of a Gaussian field and that of a normal vector... 相似文献
998.
999.
1000.
Ivan P. Kaminow 《Optical Fiber Technology》1997,3(4):279-299
As technology comes to dominate our economy and our lives, government is having a greater impact for good and bad on its directions and benefits. Government funding, regulation, and legislation can stimulate or stifle new technology. The explosion of the Internet is a perfect example of the effects of government policy on the interactions between technology and society, as I had the opportunity to discover during a year in Washington. 相似文献