全文获取类型
收费全文 | 473篇 |
免费 | 24篇 |
专业分类
化学 | 358篇 |
晶体学 | 1篇 |
力学 | 2篇 |
数学 | 52篇 |
物理学 | 84篇 |
出版年
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 8篇 |
2020年 | 16篇 |
2019年 | 9篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 12篇 |
2015年 | 19篇 |
2014年 | 16篇 |
2013年 | 34篇 |
2012年 | 41篇 |
2011年 | 55篇 |
2010年 | 32篇 |
2009年 | 31篇 |
2008年 | 42篇 |
2007年 | 34篇 |
2006年 | 32篇 |
2005年 | 19篇 |
2004年 | 10篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1975年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有497条查询结果,搜索用时 0 毫秒
491.
A. Benoit I. Paramasivam Y.-C. Nah P. Roy P. Schmuki 《Electrochemistry communications》2009,11(4):728-732
We report a simple approach to decorate ordered TiO2 nanotube (TiNT) layers with tungsten trioxide nanocrystallites by the controlled hydrolysis of a WCl6 precursor. These WO3 nanocrystallites, when formed, are amorphous, but can be annealed to a monoclinic crystal structure. The WO3 crystallites on the TiO2 nanotube skeleton are electrochemically active, and hence ion insertion reactions are possible. As a result, the decorated nanotube layers show remarkable enhancement of the electrochromic properties. In particular, a significantly lower threshold voltage and an increased electrochromic contrast can be achieved compared with unloaded (neat) TiO2 nanotube layers. 相似文献
492.
Poulomi Roy Doohun Kim Indhumati Paramasivam Patrik Schmuki 《Electrochemistry communications》2009,11(5):1001-1004
In the present work we investigate the effect of TiCl4 treatments on the photoconversion efficiency of TiO2 arrays used in dye sensitized solar cell. The results clearly show that by an appropriate treatment the decoration of the TiO2 nanotube arrays with TiO2 nanocrystallites of a typical size of 3 nm can be achieved. These particles can be converted to mixture of anatase and rutile phase by annealing in air. This decoration of the TiO2 nanotubes leads to a significantly higher specific dye loading and, for certain annealing treatments, to a doubling of the solar cell efficiency (in our case from 1.9% to 3.8% of AM 1.5 conditions) can be achieved. 相似文献
493.
How to distinguish between specular and retroconfigurations for Andreev reflection in graphene rings
We numerically investigate Andreev reflection in a graphene ring with one normal conducting and one superconducting lead by solving the Bogoliubov-de Gennes equation within the Landauer-Büttiker formalism. By tuning chemical potential and bias voltage, it is possible to switch between regimes where electron and hole originate from the same band (retroconfiguration) or from different bands (specular configuration) of the graphene dispersion, respectively. We find that the dominant contributions to the Aharonov-Bohm conductance oscillations in the subgap transport are of period h/2e in retroconfiguration and of period h/e in specular configuration, confirming the predictions obtained from a qualitative analysis of interfering scattering paths. Because of the robustness against disorder and moderate changes to the system, this provides a clear signature to distinguish both types of Andreev reflection processes in graphene. 相似文献
494.
A single pair of helical edge states as realized at the boundary of a quantum spin Hall insulator is known to be robust against elastic single particle backscattering as long as time reversal symmetry is preserved. However, there is no symmetry preventing inelastic backscattering as brought about by phonons in the presence of Rashba spin orbit coupling. In this Letter, we show that the quantized conductivity of a single channel of helical Dirac electrons is protected even against this inelastic mechanism to leading order. We further demonstrate that this result remains valid when Coulomb interaction is included in the framework of a helical Tomonaga Luttinger liquid. 相似文献
495.
496.
497.
Journal of Nonlinear Science - Exact variational integrators were exposed in the context of Lagrangian mechanics in Marsden and West (2001). These integrators sample the trajectories of holonomic... 相似文献