X.Yao
,
C.Z.Wu
,
H.Wang
,
H.M.Cheng
,
G.Q.Max Lu
材料科学技术(英文)
Hydrogen storage in traditional metallic hydrides can deliver about 1.5 to 2.0 wt pct hydrogen but magnesium hydrides can achieve more than 7 wt pct. However, these systems suffer from high temperature release drawback and chemical instability problems. Recently, big improvements of reducing temperature and increasing kinetics of hydrogenation have been made in nanostructured Mg-based composites. This paper aims to provide an overview of the science and engineering of Mg materials and their nanosized composites with nanostructured carbon for hydrogen storage. The needs in research including preparation of the materials, processing and characterisation and basic mechanisms will be explored. The preliminary experimental results indicated a promising future for chemically stable hydrogen storage using carbon nanotubes modified metal hydrides under lower temperatures.
关键词:
Hydrogen storage
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null
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null
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null
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null
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苏钰
,
符仁钰
,
李麟
上海金属
doi:10.3969/j.issn.1001-7208.2004.04.003
将St12Q1和St37-2G钢在两相区不同温度下加热和淬火,可以得到(F+M)的双相组织,与此同时研究实验用钢在不同热处理工艺下组织和力学性能的关系.结果表明:其应力-应变曲线表现出屈服点低、连续屈服、没有明显的屈服点等特性;提高两相区的淬火温度,可使马氏体量增多;在相同淬火加热温度下,淬火组织的马氏体量随钢的含碳量增加而增多;双相钢的强度只与它所含的马氏体量有关,而与马氏体中的含碳量无关.
关键词:
双相钢
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金相组织
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马氏体量
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力学性能
Scripta Materialia
Nb(4)AlC(3), a new compound belonging to the MAX phases, was discovered by annealing bulk Nb(2)AlC at 1700 degrees C. The crystal structure of Nb(4)AlC(3) was determined by combined X-ray diffraction, high-resolution transmission electron microscopy and ab initio calculations. It was reported that Nb(4)AlC(3) follows the Ti(4)AlN(3)-type crystal structure. The lattice constants are a = 0.31296 nm, c = 2.41208 nm and the atomic positions are Nb1 at 4f (1/3, 2/3, 0.0553), Nb2 at 4e (0, 0, 0.1574), Al at 2c (1/3, 2/3, 1/4), C1 at 2a (0, 0, 0) and C2 at 4f (2/3, 1/3, 0.1086). (c) 2007 Published by Elsevier Ltd. on behalf of Acta Materialia Inc.
关键词:
Nb(4)AlC(3);ceramics;crystal structure;thin-films;ti3sic2;ti4aln3;ta4alc3;microstructure;deformation;carbides;ti3alc2;growth
张炳涛
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滕冰
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钟德高
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曹丽凤
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李建宏
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人工晶体学报
采用提拉法生长出Ybb0.005Y0.708Lu0.287VO4晶体.在室温下,对Yb0.005Y0.708Lu0.287VO4晶体进行了XRPD测试,计算了晶格常数(a=b=0.7091 nm,c=0.6273 nm)和密度(4.826 g/cm3).对混晶的(100)面进行了腐蚀,腐蚀坑呈四棱锥形状.平均线膨胀系数α1=1.285×10-6 K-1,α3=7.030 ×10-6 K-1,温度在330.15 K和570.15 K之间变化时,比热为0.494 ~0.617 J/g·K.
关键词:
钒酸盐晶体
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腐蚀坑
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膨胀系数
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比热
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热导率