全文获取类型
收费全文 | 117126篇 |
免费 | 21226篇 |
国内免费 | 13460篇 |
专业分类
化学 | 81543篇 |
晶体学 | 1354篇 |
力学 | 7503篇 |
综合类 | 924篇 |
数学 | 13887篇 |
物理学 | 46601篇 |
出版年
2024年 | 287篇 |
2023年 | 2389篇 |
2022年 | 4119篇 |
2021年 | 4086篇 |
2020年 | 4845篇 |
2019年 | 4511篇 |
2018年 | 3987篇 |
2017年 | 3707篇 |
2016年 | 5652篇 |
2015年 | 5472篇 |
2014年 | 6731篇 |
2013年 | 8685篇 |
2012年 | 10586篇 |
2011年 | 11133篇 |
2010年 | 7553篇 |
2009年 | 7383篇 |
2008年 | 7866篇 |
2007年 | 6987篇 |
2006年 | 6448篇 |
2005年 | 5266篇 |
2004年 | 4182篇 |
2003年 | 3234篇 |
2002年 | 3091篇 |
2001年 | 2645篇 |
2000年 | 2321篇 |
1999年 | 2405篇 |
1998年 | 2072篇 |
1997年 | 2005篇 |
1996年 | 1970篇 |
1995年 | 1664篇 |
1994年 | 1470篇 |
1993年 | 1234篇 |
1992年 | 1055篇 |
1991年 | 982篇 |
1990年 | 798篇 |
1989年 | 625篇 |
1988年 | 475篇 |
1987年 | 401篇 |
1986年 | 395篇 |
1985年 | 326篇 |
1984年 | 206篇 |
1983年 | 153篇 |
1982年 | 127篇 |
1981年 | 80篇 |
1980年 | 62篇 |
1979年 | 26篇 |
1977年 | 8篇 |
1976年 | 15篇 |
1975年 | 14篇 |
1957年 | 34篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
Hongling Yu Heyong Wang Galia Pozina Chunyang Yin Xiao-Ke Liu Feng Gao 《Chemical science》2020,11(41):11338
Metal halide perovskites have demonstrated impressive properties for achieving efficient monochromatic light-emitting diodes. However, the development of white perovskite light-emitting diodes (PeLEDs) remains a big challenge. Here, we demonstrate a single-emissive-layer all-perovskite white PeLED using a mixed halide perovskite film as the emissive layer. The perovskite film consists of separated mixed halide perovskite phases with blue and red emissions, which are beneficial for suppressing halide anion exchange and preventing charge transfer. As a result, the white PeLED shows balanced white light emission with Commission Internationale de L''Eclairage coordinates of (0.33, 0.33). In addition, we find that the achievement of white light emission from mixed halide perovskites strongly depends on effective modulation of the halide salt precursors, especially lead bromide and benzamidine hydrochloride in our case. Our work provides very useful guidelines for realizing single-emissive-layer all-perovskite white PeLEDs based on mixed halide perovskites, which will spur the development of high-performance white PeLEDs.We demonstrated a single-emissive-layer all-perovskite white light-emitting diode based on a mixed halide perovskite film. 相似文献
42.
In the paper, the authors establish several integral representations for the generating functions of the large and little Schröder numbers and for the large and little Schröder numbers. 相似文献
43.
A Savitzky–Golay filtering for smoothing and peak search written in Python is presented in this paper alongside its applications in the list-mode digital data acquisition dual gamma–gamma coincidence bismuth germanate (BGO) detector. The study has demonstrated that the software provides a reliable and effective way to quantify trace amounts of 22Na and 7Be in aerosol samples collected at Resolute Bay, Canada with a critical limit of 3 mBq and 5 Bq respectively for a 20 h counting interval, which are believed to be the inherent limitations of the dual-BGO system.
相似文献44.
45.
We study the full counting statistics of transport electrons through a semiconductor two-level quantum dot with Rashba spin–orbit (SO) coupling, which acts as a nonabelian gauge field and thus induces the electron transition between two levels along with the spin flip. By means of the quantum master equation approach, shot noise and skewness are obtained at finite temperature with two-body Coulomb interaction. We particularly demonstrate the crucial effect of SO coupling on the super-Poissonian fluctuation of transport electrons, in terms of which the SO coupling can be probed by the zero-frequency cumulants. While the charge currents are not sensitive to the SO coupling. 相似文献
46.
Jing Zhihong Ling Baoping Yu Yang Qi Wei Zhang Shufang 《Journal of Sol-Gel Science and Technology》2015,73(1):112-117
Journal of Sol-Gel Science and Technology - A novel gas sensing material, La–Y co-doped TiO2 nanoparticles, was synthesized by sol–gel method and applied to detect organic pollutants... 相似文献
47.
48.
Qin Yin Shou-Guo Wang Xiao-Wei Liang De-Wei Gao Jun Zheng Shu-Li You 《Chemical science》2015,6(7):4179-4183
An organocatalytic asymmetric chlorinative dearomatization of naphthols was realized for the first time, providing chiral naphthalenones with a Cl-containing all-substituted stereocenter in excellent yields and enantioselectivity (up to 97% yield and 96% ee). The reaction features mild reaction conditions, good tolerance of diverse functional groups and simple reaction operation. 相似文献
49.
Nonlinear Dynamics - With an increasing number of people sharing feelings and opinions online, the online platforms have become one of the most important channels for public opinion dissemination.... 相似文献
50.