全文获取类型
收费全文 | 60篇 |
免费 | 8篇 |
国内免费 | 17篇 |
专业分类
化学 | 40篇 |
晶体学 | 2篇 |
力学 | 1篇 |
数学 | 14篇 |
物理学 | 28篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 11篇 |
2012年 | 2篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2009年 | 4篇 |
2008年 | 6篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1978年 | 1篇 |
排序方式: 共有85条查询结果,搜索用时 15 毫秒
1.
2.
Eugene A. Kotomin Yuri A. Mastrikov Rotraut Merkle Joachim Maier 《Current Opinion in Electrochemistry》2020
The efficiency of solid oxide fuel cells (SOFC) depends critically on materials, in particular for the cathode where the oxygen reduction reaction (ORR) occurs. Typically, mixed conducting perovskite ABO3-type materials are used for this purpose. The dominating surface terminations are (001) AO and BO2, with the relative fractions depending on materials composition and ambient conditions.Here, results of recent large-scale first principles (ab initio) calculations for the two alternative polar (La,Sr)O and MnO2 (001) terminations of (La,Sr)MnO3 cathode materials are discussed. The surface oxygen vacancy concentration for the (La,Sr)O termination is more than 5 orders of magnitude smaller compared to MnO2, which leads to drastically decreased estimated ORR rates. Thus, it is predicted for prototypical SOFC cathode materials that the BO2 termination largely determines the ORR kinetics, although with Sr surface segregation (long-term degradation) its fraction of the total surface area decreases, which slows down cathode kinetics. 相似文献
3.
4.
5.
为提高土壤多元素同时检测的效率,采用超级微波消解-电感耦合等离子体发射光谱法测定土壤中钾、钠、钙、镁、铜、铁、锰、锌、磷、硫、硼、砷、镉、铬、铅、钴、镓、锂等18种元素含量。比较了超级微波消解、常规微波消解和电热板消解的处理效果,采用超级微波消解法对样品进行前处理,并优化了消解条件。在最优条件下,各元素的检出限在0.05~20 mg/kg,加标回收率在86.2%~107.5%,RSD在0.1%~3.0%,方法准确度及精密度可以满足多元素同时测定的需求,且该方法具有简单、快速、成本低、用酸量少、重现性好等特点。 相似文献
6.
In this paper we study the dispersion relation of thermal non-neutral plasma column by MHD theory. We use the dispersion relation to discuss the stability and dispersive properties in a non-neutral plasma-filled waveguide. The results are in agreement with those of cold non-neutral plasma. 相似文献
7.
The overlap of magnetization of the giound state in a RKKY spin glass system with the Dzyaloshinsky-Moriya interaction is studied based on the theory of infinite number of order parameter. It is shown that the nonmagnetic impurities are coupled with the host lattice.The results are in good agreement with experiments. 相似文献
8.
9.
10.
Yuli YA. Gotlib 《Macromolecular Symposia》1999,146(1):81-87
The dynamic network model taken into account the friction relative to incompressible effective viscous medium (EVM), the hydrodynamic interactions of a network with the EVM, and the interchain friction is considered. Two collective network relaxation spectra (RS) arise. The first RS corresponds to the network motion relative to immobile EVM, the EVM does not take part in this motion. The second RS includes the combined viscous motion of the network and EVM because of long-range hydrodynamic interactions. This RS is finite and narrow for infinitely large network. The symmetry of this motion is in concordance with that of incompressible EVM. The existence of interchain friction leads to the narrowing of both types of relaxation spectra. 相似文献