LI Guodong
,
D U Ting
,
Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
China LI Guodong
,
Department No.16
,
Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
100081
,
China
金属学报(英文版)
The thermodynamic properties of Cu-Ce-S and Cu-Y-S liquid solutions were studied by the chemical equilibrium technique at 1200℃. The equilibrium constants and the standard free energies of formation of CeS and YS were determined for the reactions: CeS=[Ce]+[S] and YS = [Y]+[S] . For the solution of Ce_(1) and Y_(l) in pure Cu according to the reactions: Ce_(1)= [Ce] and Y_(1)= [Y] , the standard free energies of solutions were obtained. The first order and second order interaction coefficients between solute elements as well as the activity coefficients γ_(Ce)~0 and γ_Y~0 in liquid Cu were also determined.
关键词:
Cu-Ce-S system
,
null
,
null
Computer Physics Communications
Based on a detailed check of the LDA + U and GGA + U corrected methods, we found that the transition energy levels depend almost linearly on the effective U parameter. GGA + U seems to be better than LDA + U, with effective U parameter of about 5.0 eV. However, though the results between LDA and GGA are very different before correction, the corrected transition energy levels spread less than 0.3 eV. These more or less consistent results indicate the necessity and validity of LDA + U and GGA + U correction. (C) 2012 Elsevier B.V. All rights reserved.
关键词:
Band-gap problems;LDA plus U and GGA plus U;ZnO;First-principles;augmented-wave method
李赣
,
余慧龙
,
银陈
稀有金属材料与工程
采用广义梯度密度泛函理论研究了H2O分子在α-U(001)表面上的吸附、扩散和解离.结果表明,H2O分子在a-U(001)表面的最稳定构型为平行于表面的顶位吸附结构,吸附能为0.58 eV.吸附作用主要源于H2O分子1b1轨道与表面U原子6d轨道的空间交叠,同时伴有弱的H2O 3aα1-U 6d轨道交叠.近邻顶位间H2O分子的扩散能垒为0.20～0.23 cV,预示H2O分子易于在a-U(001)表面发生扩散迁移.OH+H解离吸附较分子吸附在能量上高1.24～1.39 eV,解离能垒为0.56～0.62 eV,预示一定热激活条件下,吸附H2O分子趋向解离形成OH基团和H原子.
关键词:
密度泛函理论
,
α-U(001)表面
,
H2O分子
,
吸附
鲜晓斌
,
刘柯钊
,
吕学超
,
张永彬
稀有金属材料与工程
用循环Ar+轰击-磁控溅射离子镀(MSIP)法在U表面上镀Al,Ti/Al,并采用俄歇电子能谱仪(AES)、扫描电镜(SEM)、电化学实验和平面磨耗实验,研究了其表面、剖面形貌和耐磨耐蚀性能,以及Al/U和Ti/Al镀层界面.结果表明:U上循环Ar+轰击-磁控溅射离子镀Al,Ti/Al界面存在较宽的原子共混区,且Ti/Al镀层的耐磨耐蚀性能明显优于单一磁控溅射离子镀Al层.
关键词:
Ti/Al镀层
,
界面
,
耐磨性
,
耐蚀性
伏晓国
,
刘柯钊
,
汪小琳
,
柏朝茂
,
赵正平
,
蒋春丽
金属学报
采用X射线光电子能谱(XPS)分析研究了298 K时O2在金属U和U Nb合金清洁表面的原位吸附过程,作为对照还研究了在纯Nb表面的吸附.吸附各阶段XPS图谱的变化揭示了O2在U,Nb和U-Nb合金表面的吸附将导致UO2,NbO和Nb2O5等多种产物形成定量分析表明,O2在U和U-Nb合金表面的饱和吸附量大约分别为45 L和40 L(1 L=L33x10-4Pa.s),而O2在金属Nb上的饱和吸附量仅约为10 L.
关键词:
合金
,
null
,
null
伏晓国
,
刘柯钊
,
汪小琳
,
柏朝茂
,
赵正平
,
蒋春丽
金属学报
doi:10.3321/j.issn:0412-1961.2001.06.004
采用X射线光电子能谱(XPS)分析研究了298 K时O2在金属U和U Nb合金清洁表面的原位吸附过程,作为对照还研究了在纯Nb表面的吸附.吸附各阶段XPS图谱的变化揭示了O2在U,Nb和U-Nb合金表面的吸附将导致UO2,NbO和Nb2O5等多种产物形成定量分析表明,O2在U和U-Nb合金表面的饱和吸附量大约分别为45 L和40 L(1 L=L33x10-4Pa@s),而O2在金属Nb上的饱和吸附量仅约为10 L.
关键词:
O2
,
U
,
U-Nb合金
,
表面吸附
,
X射线光电子谱
