G.F. Zhou
,
M. B. Wen
,
P. H. Li and X. L. He 1) National Enterprise Technology Center
,
Wuhan Iron & Steel Group Co.
,
Wuhan 430080
,
China 2) University of Science and Technology Beijing
,
Beijing 100083
,
China
金属学报(英文版)
The stress relaxation curves of Ultra-Low Carbon Bainitic(ULCB) steels with different Cu and B contents were measured by using Gleeble-1500 dynamic thermal-mechanical simulator. The results show that Cu and B added can accelerate the strain-induced precipitation reaction, and the effect of Cu and B is even more obvious with Cu and B combined addition or Cu content increased. The TEM analysis of precipitate engendered at the temperature of 850℃ C indicate that Nb(C,N) precipitate nucleates dominantly on the dislocation line, and grows with holding time extended while the precipitate particle size increases from 5 nm to 17 nm.
关键词:
stress relaxation
,
null
,
null
曹笃盟
,
李志友
,
周科朝
稀有金属材料与工程
采用固相反应法制备了Li1+xV3-yMyO8(M=Mo,P;0≤y≤0.4),研究了不同Mo和P含量对Li1+xV3O8相的影响,并首次对其进行了高温阴极放电性能的研究.结果表明:Mo和P掺杂量分别为y≤0.2和y＜0.2时可获得纯Li1+xV3O8相;Mo掺杂使Li1+xV3O8峰值电压提高0.3 V,比容量提高25%,嵌入的Li+量最高可达x=3.8;P掺杂(y≤0.20)对Li1+xV3O8的峰值电压和比容量影响较小.化学嵌锂实验也证实掺杂后的材料具有更快的Li+嵌入速度.
关键词:
Li1+xV3O8
,
热电池
,
掺杂
,
比容量
Physica Status Solidi a-Applications and Materials Science
In MnAs(1-x)P(x) compounds (x = 0.006 and 0.01), prepared by mechanical alloying, the thermal hysteresis is greatly reduced from about 10-30K in MnAs-based compounds, prepared by conventional melting, to 2K for x = 0.01 (or 4K for x = 0.006). Such obvious hysteretic reduction is ascribed to the grain-size effect, largely due to the preparation method of mechanical alloying. Meanwhile, a maximum value of the magnetic-entropy change Delta S(M) of 11.3 J/kgK for a field change of 2 T is obtained at 294.5K for MnAs(0.994)P(0.006). The study on the MnAs(1-x)P(x) system and also the effect of the preparation technology may be beneficial for the realization of magnetic refrigerants for application at room temperature. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
关键词:
magnetocaloric effect;mechanical alloying;thermal hysteresis;gd-5(si2ge2);transition;mnas
胡义华
,
刘美希
,
陈丽
,
王小涓
,
储焰南
,
曹德兆
量子电子学报
doi:10.3969/j.issn.1007-5461.2001.04.008
本文在流动余辉装置上,研究了亚稳态He(23S)原子与N2H4分子碰撞传能,观察到了激发态产物NH(A3II→X3∑+)、NH(c1II→a1△)、NH2(A2A1→X2B1)的发射光谱,由相对光谱强度求得了形成各产物的通道比;分析NH(A3II,v＇=0)的转动分辨谱的结果表明,v＇=0能级上的转动布居是"双模”分布,激发态产物NH(A)、NH2(A)的形成机理可能是: He(23S)+N2H4→N2H4*→NH(A)+NH2(A)+H.
关键词:
碰撞传能
,
化学发光
,
NH(A3Ⅱ)的发射光谱
卢洋藩
,
叶志镇
,
曾昱嘉
,
陈兰兰
,
朱丽萍
,
赵炳辉
无机材料学报
doi:10.3724/SP.J.1077.2006.01511
采用Li-N-H共掺技术在玻璃衬底上生长p型ZnO薄膜. XRD结果表明共掺ZnO薄膜具有高度cll轴取向, Hall测试表明薄膜的电阻率为25.2Ω·cm, Hall迁移率为0.5cm2/(V·s), 空穴浓度为4.92×1017/cm3. 此外, p-ZnO薄膜在可见光区域具有90%的高透射率.
关键词:
p-ZnO
,
magnetron sputtering
,
codoping
卢洋藩
,
叶志镇
,
曾昱嘉
,
陈兰兰
,
朱丽萍
,
赵炳辉
无机材料学报
doi:10.3321/j.issn:1000-324X.2006.06.039
采用Li-N-H共掺技术在玻璃衬底上生长p型ZnO薄膜.XRD结果表明共掺ZnO薄膜具有高度c轴取向,Hall测试表明薄膜的电阻率为25.2Ω·cm,Hall迁移率为0.5cm2/(V·s),空穴浓度为4.92×1017/cm3.此外,p-ZnO薄膜在可见光区域具有90%的高透射率.
关键词:
p-ZnO
,
磁控溅射
,
共掺
赵中伟
,
刘旭恒
中国有色金属学报
运用同系线性规律对Li-Fe-P-H2O系中缺少的LiFePO4和Li3PO4的△GΘ进行估算.结合已有的热力学数据,运用ψ-pH图的绘制原理,得到25℃时Li-Fe-P-H2O系在不同浓度下的ψ-pH图.结果表明,在水溶液中,LiFePO4具有较大的热力学稳定区域,这对湿法制备LiFePO4很有利.根据所绘制的热力学平衡图,详细讨论了各种LiFePO4软化学制备方法的可行性途径,并就液相法制备LiFePO4可能的技术途径和条件进行分析,为在水溶液中用软化学法制备LiFePO4提供理论依据.
关键词:
Li-Fe-P-H2O系
,
磷酸铁锂
,
热力学
Journal of Alloys and Compounds
The spin Hamiltonian (SH) parameters (g factors g(x), g(y), g(z) and hyperfine structure constants A(x), A(y), A(z)) of the low-symmetry Nb-Li(4+) antisite defect center in the X-ray-irradiated congruent undoped LiNbO3 crystal are calculated from the high-order perturbation formulas of SH parameters for d(1) ions. The calculated results are in reasonable agreement with the experimental values. Some information related to the defect structure of the Nb-Li(4+) center (characterized mainly by the Nb-Li(4+) displacement Delta z from the ideal Li+ site along C-3 axis and the displacement Delta x of O2- ions in the oxygen triangle between Nb-Li(4+) and Nb-Nb(5+)) is obtained from the calculations. These displacements are consistent with the expectation based on the electrostatic interaction and electron cloud overlap. The results are discussed. (C) 2006 Elsevier B.V. All rights reserved.
关键词:
ferroelectrics;inorganic compounds;crystal and ligand fields;point;defect;electron paramagnetic resonance (EPR);temperature-dependence;lithium-niobate;epr parameters;cr3+ centers;endor;ions;ruby
Intermetallics
The well-densified Ni(3)Al alloys without and with boron addition were fabricated by self-propagation high-temperature synthesis and hot extrusion (SHS/HE) technology. Microstructure investigation showed that Ni(3)Al and Ni(3)Al-1B alloys contained fine grain structure. Analysis of X-ray spectra as well as transmission electron microscopy studies revealed that three phases present in all alloys: gamma-Ni, Ni(3)Al and dispersoids of alpha- Al(2)O(3) and gamma- Al(2)O(3). However, beta-NiAl, Ni(3)B phase and twinned Ni(3)Al crystal are observed in the Ni(3)Al-1B alloy. In addition, dislocations with high density exist in all alloys. The mechanical test showed that the B addition leads to obvious improvement in yield strength and compressive ductility, and compared with the ones synthesized by combustion, SHS/HE synthesized Ni(3)Al and Ni(3)Al-1B alloys exhibit more excellent mechanical properties. (C) 2010 Elsevier Ltd. All rights reserved.
关键词:
Nickel aluminides, based on Ni(3)Al;Mechanical properties at ambient;temperature;Reaction synthesis;Microstructure;combustion synthesis;nickel;aluminides;boron
