Physical Review B
In a recent publication [S. Dong et al., Phys. Rev. Lett. 103, 127201 (2009)], two (related) mechanisms were proposed to understand the intrinsic exchange bias present in oxides heterostructures involving G-type antiferromagnetic perovskites. The first mechanism is driven by the Dzyaloshinskii-Moriya interaction, which is a spin-orbit coupling effect. The second is induced by the ferroelectric polarization, and it is only active in heterostructures involving multiferroics. Using the SrRuO(3)/SrMnO(3) superlattice as a model system, density-functional calculations are here performed to verify the two proposals. This proof-of-principle calculation provides convincing evidence that qualitatively supports both proposals.
关键词:
thin-films;weak ferromagnetism;superlattices;anisotropy;bifeo3;srruo3;model
刘建平
,
苗永霞
,
周晓湘
材料保护
doi:10.3969/j.issn.1001-1560.2005.08.007
为了减缓酸洗过程中金属制品的严重腐蚀,酸洗缓蚀剂被广泛使用,开发使用方便、低毒、低剂量、环保的酸洗缓蚀剂很有意义.利用失重法、动电位扫描法和电化学交流阻抗法对复配咪唑啉类缓蚀剂LAN的耐蚀性能进行了研究.结果表明:在50 ℃的5%(质量分数)盐酸中加入0.3% (质量分数)的LAN能有效地提高碳钢的耐蚀性能;LAN的缓蚀作用机理系几何覆盖效应,它在金属表面吸附成膜后,使阴极和阳极过程都受到了阻滞.同时,根据EIS谱提出了相应的特征等效电路.
关键词:
缓蚀剂
,
咪唑啉类
,
缓蚀效率
,
极化曲线
,
交流阻抗
,
等效电路
