Chun-Nian He
,
Chao Feng
,
Ji-Chuan Lin
,
En-Zuo Liu
,
Chun-Sheng Shi
,
Jia-Jun Li
,
Nai-Qin Zhao
金属学报(英文版)
doi:10.1007/s40195-016-0376-3
Carbon nanotube (CNT)-reinforced 6061Al alloy matrix composites were prepared by chemical vapor deposition (CVD) combined with hot extrusion technique. During the preparation process, the 6061Al flakes obtained by ball milling of the 6061Al spherical powders were subjected to surface modification to introduce a hydrophilic polyvinyl alcohol (PVA) membrane on their surface (6061Al@PVA) to bond strongly with nickel acetate [Ni(II)]. Then the 6061Al@PVA flakes bonded with Ni(II) were calcined and reduced to Ni nanoparticles, which were then heat-treated at 580 °C to remove PVA for obtaining even Ni/6061Al catalyst. After that, the as-obtained Ni/6061Al catalyst was employed to synthesize CNTs on the surface of the 6061Al flakes by CVD. After hot extrusion of the CNT/6061Al composite powders, the as-obtained CNT/6061Al bulk composites with 2.26 wt% CNTs exhibited 135% increase in yield strength and 84.5% increase in tensile strength compared to pristine 6061Al matrix.
关键词:
Metal
,
matrix
,
composites
,
(MMCs)
,
Microstructure
,
Mechanical
,
properties
,
Carbon
苏晓斌
,
刘洋
,
侯龙
,
王朝辉
,
王琦
原子核物理评论
doi:10.11804/NuclPhysRev.32.04.440
低能D(d,γ)4 He辐射俘获反应截面的研究在聚变领域和天体物理等领域中起到非常重要的作用。由于受到标准γ源能量的制约，在研究D(d,γ)4 He反应产生的23.8 MeV高能γ射线产额实验过程中不能用标准源进行效率刻度。采用实验测量与计算相结合的方法实现NaI(Tl)探测器对23.8 MeV γ射线的效率刻度是比较成熟可靠的。针对高能γ射线的产额低、本底大的情况，实验采用一个大型NaI(Tl)反康谱仪进行测量，以提高探测效率。NaI(Tl)探测器的效率，独特地采用了包括全能峰、单逃逸峰和双逃逸峰在内的效率来计算，经MCNP-4C程序模拟计算，结合实验测量的19 F(p,αγ)16 O反应产生的6.13 MeV γ射线探测效率推算出该NaI(Tl)探测器在23.8 MeV的效率为(2.23±0.34)‰。该方法对研究高能γ射线效率刻度具有重要的参考价值。
关键词:
NaI(Tl)探测器
,
能量
,
γ射线
,
效率刻度
,
MCNP-4C
刘慧强
,
凤仪
,
张学斌
,
李斌
,
余东波
,
朱艳芳
,
刘晓燕
材料热处理学报
采用通孔泡沫铝作基体的＂包壳密封法＂制备高含量NaI的Al-NaI放射性嬗变靶材。分别在20、50和80℃的蒸馏水中对未烧结和烧结过的Al-NaI放射性嬗变靶材进行水化学稳定性试验。用AAS-800原子吸收光谱仪对浸出时间分别为24、48、72和96 h的浸出溶液进行浓度测量,从而计算出不同条件下各种嬗变靶材在蒸馏水中的浸出率。结果表明,烧结后的靶材浸出率不会超过10%,远远低于未烧结的靶材,满足NaI嬗变率测量的实验要求。
关键词:
泡沫铝
,
Al-NaI靶材
,
水化学稳定性
,
浸出率
中国腐蚀与防护学报
N。1Atmospheric Corrosivlty for Steels………………………………………………… .LIANG Caideng HO[I i。-tat（6）Caustic Stress Corrosion Cr。king of Alloy 800 Part 2.The Effect of Thiosul执e……………………………………… KONG De-sheng YANG Wu ZHAO Guo-zheng HUANG De.ltL。ZHANG Yu。。he CHEN She。g-bac（13）SERS slid E16CttOCh6iniC81 Stlldy Of Illhibit1Oli M6ch＆tllsth Of ThlollY68 Oil ITOll ID H....
关键词:
Europhysics Letters
Noncollinear magnetic investigations of the ground state in PrFeAsO have been performed by the density-functional theory. We calculated the total energy and made structure optimization, and the electronic density of states of PrFeAsO was analyzed. There are three different magnetic structures in PrFeAsO defined by experiments. Based on these magnetic structures, we studied four collinear and four noncollinear cases. The ground state is found to take the ordering proposed by Zhao, in which the FeAs plane is of stripe antiferromagnetism and Pr spins are perpendicular to Fe spins. The electronic density of states indicates that for PrFeAsO the increase of the electron Coulomb interaction leads to a decrease in conductivity. Copyright (C) EPLA, 2011
关键词:
high-temperature superconductivity;phase-diagram;oxypnictides;instability
任秋鹤
,
黄义争
,
马红
,
高进
,
徐杰
催化学报
doi:10.1016/S1872-2067(14)60012-7
研究了碱金属卤化物对AlCl3催化葡萄糖转化制备5-羟甲基糠醛(HMF)的促进作用。结果表明, NaF对反应有显著抑制作用,而NaI和NaBr对反应有显著促进作用,而且NaI比NaBr的促进效果更明显。在N,N-二甲基乙酰胺(DMAC)中,以NaI为添加剂,130oC反应15 min, AlCl3催化葡萄糖转化制备HMF,葡萄糖转化率由71%提高到86%, HMF收率由36%提高到62%。 AlCl3-NaI-DMAC体系也可用于果糖、甘露糖等单糖,蔗糖、麦芽糖、纤维二糖等二糖,以及菊粉等多糖的转化。以蔗糖为原料, HMF收率可达63%。
关键词:
糖类化合物
,
5-羟甲基糠醛
,
金属卤化物
,
催化
