材料期刊网

EFFECT OF ANNEALING ON THE ELECTRODE PERFORMANCES OF ZrTi(MnVCoNi)_2 HYDROGEN STORAGE ALLOY

X.G , Yang , Q.A. Zhang , K. Y Shu , YL. Du , YQ. Lei and Q.D. Wang (Department of Materials Science and Engineering , Zhejiang University , Hangzhou 310027 , China )W.K. Zhang(Department of Applied Chemistry , Zhejiang University of Technology , Hangzhou 3100l4 , China )G.L. Lu(Central Lab , Zhejiang University , Hangzhou 310028 , China)

金属学报(英文版)

The annealing treatment was found to improve the cyclic stability but to degmde discharpe capacity, activation and high-rate discharpeability for the Ti-substituted AB2type alloy electrode. A larper polarization was found in the annealed alloy because of its poor discharpe kinetics resulted hem the structural homogeneity. At larae discharpe cumnts, the hydmpen dchsion in the bulk of the alloy was mpaofed as the mte-determining step. Based on the P ressure-composition isotherm measurement, we concluded that the decrease in discharpeability of the annealed alloy is owing to the low and flat pressure plateau, as well as the large hysteresis, but the hydrgen stomge density almost remains unchangeable after annealing.

关键词: AB_2 , null , null , null , null , null

WT-MV3100拍摄与测量软件在金相分析中的应用研究

李占坚

材料开发与应用 doi:10.3969/j.issn.1003-1545.2010.05.013

采用WT-MV3100拍摄与测量软件在金相分析中测量某一组织所占比例,替代人工目测比较估计测定,迅速、准确地完成金相图像采集拍摄 、图像数据获取、级别评定以及资料保存、打印等工作,大大提高了组织测定的准确性和效率.

关键词: 金相分析 , 拍摄与测量软件 , 准确性 , 效率

First-principle study on the electronic structure and ferromagnetic properties of a three-dimensional coordination polymer: Cu(HCO2)(2)L (L=4,4 '-bipyridine)

Physica B-Condensed Matter

We have employed the full-potential linearized augmented plane-wave method with generalized gradient approximation to study the electronic structure and the magnetic properties of the three-dimensional coordination polymer Cu(HCO2)(2)L (L = 4,4'-bipyridine). The atomic magnetic moments, and the total and partial density of states indicate that the magnetic moments mainly come from the Cu atom, and there exists a ferromagnetic interaction between the Cu2+ ions. The total density of states also shows that the compound is an insulator. The total energies of three possible magnetic phases reveal that this compound has the ferromagnetic ground state, which is in agreement with the experiment. (C) 2007 Elsevier B.V. All rights reserved.

关键词: density-function theory;electronic structure;ferromagnetic properties;organic ferromagnets;magnetic-properties;molecular magnets;temperature;surfaces;chains;model

The ferromagnetic copper (II)-azido compound Cu(L)(2)(N-3)(2) (n) L=4-(dimethylamino)pyridine studied by first-principle calculation

Physica B-Condensed Matter

Cu2+ ions are doubly bridged by asymmetrical end-to-end (EE) azido groups in copper (II)-azido compound [Cu(L)(2)(N-3)(2)](n) [L = 4-(dimethylamino)pyridine]. The electronic structure of its ferromagnetic ground state has been calculated using the self-consistent full-potential linearized augmented plane wave method (FP_LAPW) based on the density functional theory (DFT). The result shows that spin distribution and ferromagnetic coupling in the title compound are dominated by the spin delocalization effect from Cu2+ ions toward the azido groups, but weak spin polarization effects also contribute to the magnetic coupling through the asymmetrical EE azido groups. (c) 2005 Elsevier B.V. All rights reserved.

关键词: [Cu(L)(2)(N-3)(2)](n);azido group;spin delocalization;end-to-end;magnetostructural correlations;magnetic-properties;molecular magnets;crystal-structure;on azido;antiferromagnetic;interactions;nickel(ii) complexes;dinuclear complex;bridges

L-半胱氨酸改性Fe3O4纳米粒子的水热合成及其应用

李波 , 黄忠兵 , 孟宪伟 , 唐芳琼

影像科学与光化学 doi:10.7517/j.issn.1674-0475.2014.02.163

以L-半胱氨酸为表面改性剂与粒径调节剂,采用水热法制备具有良好分散稳定性的磁性Fe3 O4纳米粒子.通过透射电镜(TEM)、扫描电镜(SEM)、X射线衍射仪(XRD)、比磁饱和强度测定仪(VSM)等对产物进行表征,研究L-半胱氨酸对磁性Fe3O4纳米粒子的形貌、粒径分布、晶型结构、分散稳定性等的影响,理论推导了L-半胱氨酸改性后的Fe3O4纳米粒子(L-Fe3O4纳米粒子)的生成机制,将该材料作为载体吸附金种后探讨其在催化对硝基苯酚方面的应用.结果表明:沉降22 h时,调节pH值为7.0制备的Fe3O4纳米粒子的沉降高度大约是L-Fe3O4纳米粒子的6.5倍;吸附金种后的L-Fe3O4纳米粒子催化效率大约是未改性Fe3O4纳米粒子的5倍.L-半胱氨酸有效的改善了Fe3O4纳米粒子与分散介质之间的相容性,保护并改善了纳米粒子的分散稳定性,在污水处理等方面有潜在的应用.

关键词: 水热法合成 , Fe3O4纳米粒子 , L-半胱氨酸 , 分散稳定性

ND、2205、17-4PH和316L不锈钢材料的腐蚀行为

周梓荣 , 肖鑫

电镀与涂饰

针对含少量杂质的稀硫酸在高温环境下的强腐蚀性,选了ND、2205、17-4PH和316L等不锈钢材料,在5%NaCl溶液和现场提取的工作介质中进行了60～80 ℃工作温度下的腐蚀性试验.结果表明,在5%NaCl溶液中,ND不锈钢耐蚀性能最好;在工作介质中,17-4PH不锈钢的耐蚀性最好.

关键词: 不锈钢 , 腐蚀行为 , 稀硫酸 , 耐蚀性

4-(6-羟基己氧基)联苯-4'-甲酸-L-2甲基丁醇酯的合成及其液晶性的研究

沈金平 , 章于川 , 范程士 , 张彩云 , 李国喜

液晶与显示 doi:10.3969/j.issn.1007-2780.2006.01.003

运用示差扫描量热仪、偏光显微镜、X射线衍射仪和计算机模拟分子链处于能量最低、最优构象时的分子长度等手段,对新合成的4-(6-羟基己氧基)联苯-4'-甲酸-L-2甲基丁醇酯进行表征.结果表明:该液晶化合物为近晶A相.合成总收率为47.3 % (相对于4-羟基-4'-氰基联苯).

关键词: 铁电液晶 , 4-(6-羟基己氧基)联苯-4'-甲酸-L-2甲基丁醇酯 , 合成 , 计算机模拟

N-(4-吡啶甲基)-L-丝氨酸铜配合物的合成、晶体结构和磁性

李艳红 , 卢丽萍 , 冯思思

人工晶体学报

氨基酸还原希夫碱HL (N-(4-吡啶甲基)-L-丝氨酸)与CuCl2·2H2O在室温条件通过扩散法合成了配位聚合物{[Cu2(L)2(Cl)2]·H2O}n(I).采用元素分析、红外光谱、X-射线单晶衍射、粉末衍射和热重分析进行了表征.两个结晶学独立Cu(II) 包含于其晶体结构中,Cu1为变形八面体CuO2N2Cl2几何构型;Cu2则呈现略有变形的四方锥结构.Cu1和Cu2通过配体L-的吡啶氮原子以及氯离子的桥连作用连接为2D网状结构.变温磁化率实验表明在温度为2~300 K,配合物I表现为铁磁性耦合.

关键词: N-(4-吡啶甲基)-L-丝氨酸 , 配位聚合物 , 晶体结构 , 铁磁性

316L和45N＋双相不锈钢在食品级H3PO4中的腐蚀行为

向嵩 , 李艳丽 , 王江平 , 王权顶

材料保护

为了减少盛装食品级磷酸设备的腐蚀，采用失重法、腐蚀电位-时间曲线、扫描电镜研究了316L不锈钢和45N＋双相不锈钢在食品级H3PO4溶液中的腐蚀行为。结果表明：在55℃，85．0％H3P04溶液中，316L不锈钢的腐蚀速率大于45N＋双相不锈钢；45N＋双相不锈钢表面钝化膜形成速度比316L不锈钢的快；45N＋双相不锈钢在H3PO4溶液中具有很好的耐蚀性，受H3PO4浓度的影响较小，耐蚀性优于316L不锈钢；316L不锈钢的耐蚀性随H3PO4浓度的增加先变好后变差。

关键词: 腐蚀行为 , 食品级磷酸 , 耐蚀性 , 316L不锈钢 , 45N+双相不锈钢

激光快速成形316L不锈钢/镍基合金/Ti6Al4V梯度材料

席明哲 , 张永忠 , 涂义 , 石力开 , 金具涛

金属学报 doi:10.3321/j.issn:0412-1961.2008.07.011

用激光快速成形法制备了致密、无裂纹的316L不锈钢(SS)/镍基合金/Ti6Al4V梯度薄壁件.EDS与XRD分析显示,在316L SS/镍基合金梯度过渡区内为单相,γ奥氏体,硬度沿316L SS到镍基合金方向逐步增加;在镍基合金/Ti6Al4V梯度过渡区内,组织变化顺序为:γ→γ+β+TiNi3+Ti2Ni→TiNi3+Ti2Ni+β→Ti2Ni+β→α+β+Ti2Ni→α+β;过渡区内,Ti6Al4V含量为20%(质量分数)时,硬度达到最大值HV10 830,随后,随Ti6Al4V含量增加,硬度逐渐减小.

关键词: 激光快速成形 , 梯度材料 , 不锈钢 , 镍基合金 , 钛合金