全文获取类型
| 收费全文 | 1420篇 |
| 免费 | 173篇 |
| 国内免费 | 206篇 |
专业分类
| 化学 | 994篇 |
| 晶体学 | 70篇 |
| 力学 | 2篇 |
| 综合类 | 9篇 |
| 物理学 | 724篇 |
出版年
| 2025年 | 10篇 |
| 2024年 | 100篇 |
| 2023年 | 67篇 |
| 2022年 | 115篇 |
| 2021年 | 158篇 |
| 2020年 | 180篇 |
| 2019年 | 171篇 |
| 2018年 | 101篇 |
| 2017年 | 76篇 |
| 2016年 | 91篇 |
| 2015年 | 54篇 |
| 2014年 | 36篇 |
| 2013年 | 71篇 |
| 2012年 | 46篇 |
| 2011年 | 50篇 |
| 2010年 | 43篇 |
| 2009年 | 55篇 |
| 2008年 | 48篇 |
| 2007年 | 45篇 |
| 2006年 | 48篇 |
| 2005年 | 51篇 |
| 2004年 | 35篇 |
| 2003年 | 37篇 |
| 2002年 | 25篇 |
| 2001年 | 18篇 |
| 2000年 | 29篇 |
| 1999年 | 7篇 |
| 1998年 | 6篇 |
| 1997年 | 8篇 |
| 1996年 | 4篇 |
| 1995年 | 4篇 |
| 1994年 | 6篇 |
| 1993年 | 1篇 |
| 1989年 | 1篇 |
| 1988年 | 2篇 |
排序方式： 共有1799条查询结果，搜索用时 15 毫秒
151.
《化学:亚洲杂志》2017,12(8):882-889
Ag0.5La0.5TiO3 with an ABO3 perovskite structure was synthesized by a newly developed ion‐exchange method. Molten Ag2SO4 instead of traditional molten AgNO3 was used as Ag+ source in view of its high decomposition temperature (1052 °C), thereby guaranteeing the complete substitution of Ag+ for Na+ in Na0.5La0.5TiO3 with a stable ABO3 perovskite structure at a high ion‐exchange temperature (700 °C). Under full‐arc irradiation, the O2‐evolution activity of Ag0.5La0.5TiO3 was about 1.6 times that of Na0.5La0.5TiO3 due to the optimized electronic band structures and local lattice structures. On the one hand, the substitution of Ag+ for Na+ elevated the VBM and thus narrowed the band gap from 3.19 to 2.83 eV, thereby extending the light‐response range and, accordingly, enhancing the photoexcitation to generate more charge carriers. On the other hand, the substitution of Ag+ for Na+ induced a lattice distortion of the ABO3 perovskite structure, thereby promoting the separation and migration of charge carriers. Moreover, under visible‐light irradiation, Ag0.5La0.5TiO3 displayed notable O2 evolution whereas Na0.5La0.5TiO3 showed little O2 evolution, thus demonstrating that the substitution of Ag+ for Na+ enabled the use of visible light to evolve O2 photocatalytically. This work presents an effective route to explore novel Ag‐based photocatalysts. 相似文献
152.
《化学:亚洲杂志》2017,12(20):2727-2733
Hydrogen production by catalytic water splitting using sunlight holds great promise for clean and sustainable energy source. Despite the efforts made in the past decades, challenges still exist in pursuing solid catalysts with light‐harvesting capacity, large surface areas and efficient utilities of the photogenerated carrier, at the same time. Here, a multiple structure design strategy leading to highly enhanced photocatalytic performance on hydrogen production from water splitting in Dion–Jacobson perovskites KCa2Nan ‐3Nbn O3n +1 is described. Specifically, chemical doping (N/Nb4+) of the parent oxides via ammoniation improved the ability of sunlight harvesting efficiently; subsequent liquid exfoliation of the doped perovskites yielded ultrathin [Ca2Nan ‐3Nbn O3n +1]− nanosheets with greatly increased surface areas. Significantly, the maximum hydrogen evolution appears in the n =4 nanosheets, which suggests the most favorable thickness for charge separation in such perovskite‐type catalysts. The optimized black N/Nb4+‐[Ca2NaNb4O13]− nanosheets show greatly enhanced photocatalytic performance, as high as 973 μmol h−1 with Pt loading, on hydrogen evolution from water splitting. As a proof‐of‐concept, this work highlights the feasibility of combining various chemical strategies towards better catalysts and precise thickness control of two‐dimensional materials. 相似文献
153.
154.
155.
156.
157.
《Current Applied Physics》2020,20(5):720-737
Roll-to-roll (R2R) production is an innovative approach and is fast becoming a very popular industrial method for high throughput and mass production of solar cells. Replacement of costly indium tin oxide (ITO), which conventionally has served as the transparent electrode would be a great approach for roll to roll production of flexible cost effective solar cells. Indium tin oxide (ITO) and fluorine-doped tin oxide (FTO) are brittle and ultimately limit the device flexibility. Perovskite solar cells (PSCs) have been the centre of photovoltaic research community during the recent years owing to its exceptional performance and economical prices. The best reported PSCs fabricated by employing mesoporous TiO2 layers require elevated temperatures in the range of 400–500 °C which limits its applications to solely glass substrates. In such a scenario developing flexible PSCs technology can be considered a suitable and exciting arena from the application point of view, them being flexible, lightweight, portable, and easy to integrate over both small, large and curved surfaces. 相似文献
158.
159.
160.
《Physics letters. A》2020,384(9):126186
The phase diagrams and magnetic properties of double perovskite have been studied by using Monte Carlo simulation based on the heat bath algorithm. The ground-state diagrams of the compound have been calculated for different combinations of system parameters. The diagrams obtained are very rich and they give an idea of all the most stable configurations. The effects of the exchange interactions and the crystal field on the phase diagrams and magnetic properties of the system have been examined. A number of interesting phenomena have been observed such as the compensation temperature, the first and second order phase transitions, the critical triple point and the terminal critical point. 相似文献