材料期刊网，材料期刊，材料类期刊，材料期刊投稿

Synthesis and surface modification of cobalt nanoparticles and electromagnetic property of Co/PPy nanocomposites

Hai-Cheng Wang , Zhi-Ran Yan , Ling Deng , Hua Dong , Yi-He Jia , Ning Ma , Jun He

关键词:

Cu-Zr/ZrN薄膜体系的电阻率和纳米压入研究

采用磁控溅射方法在Si(111)基片上沉积Cu-Zr/ZrN薄膜体系作为扩散阻挡层.通过比较Cu-Zr/ZrN薄膜体系和三元非晶(Mo,Ta,W)-Si-N的电阻率,同时比较Cu-Zr/ZrN薄膜体系和Ta,YaN的硬度,说明作为扩散阻挡层的材料的选取,应从整体性能上考虑,而不能仅仅考虑热稳定性等单一指标.

关键词: 非晶 , 电阻率 , 纳米压入 , 硬度

LC4铝合金稀土转化膜耐蚀性及影响因素

张巍 , 李久青 , 许江涛 , 陈昆

腐蚀学报（英文） doi:10.3969/j.issn.1002-6495.1999.06.004

开发了IC4铝合金稀土转化膜碱性两步成膜工艺ZH1,利用正交优化设计方法确定了最佳工艺参数.采用多种实验方法研究了经ZH1处理的LC4铝合金在氯化物环境中的耐蚀性及其影响因素,结果表明:经ZHI工艺处理过的LC4铝合金耐全面腐蚀和点蚀性能均有明显提高,稀土转化膜既抑制了腐蚀的阴极过程,也抑制了阳极过程.具有ZH1转化膜的LC4铝合金对氯离子浓度和pH值的变化不甚敏感.

关键词: 高强铝合金 , 稀土转化膜 , 耐蚀性学科

丙烯酸与丙烯腈感光共聚合反应研究

喻发全 , 刘艳萍 , 黄世英 , 姚树人

高分子材料科学与工程

采用McGiniss改良膨胀计与SW-1型微位移测量仪,测定了丙烯酸(AA)-丙烯腈(AN)感光共聚合速率;用102-G气相层析仪及1106型元素分析仪对AA-AN感光聚合体系的单体浓度比及共聚物链节比进行了定量分析,按假定的反应机理计算了单体的竞聚率,在40 ℃时的结果为rAA=2.85,rAN=0.038.

关键词: 丙烯腈 , 丙烯酸 , 紫外光 , 感光共聚 , 动力学 , 竞聚率

Studies of the g factors and the local structure for Ni3+in LaAl0.9Ni0.1O3, La0.75Y0.25Al0.99Ni0.01O3 and YAl0.9Ni0.1O3

Radiation Effects and Defects in Solids

The electron paramagnetic resonance g factors and the local structure for Ni3+ in LaAl0.9Ni0.1O3 (LAN), La0.75Y0.25Al0.99Ni0.01O3 (LYAN) and YAl0.9Ni0.1O3 (YAN) are theoretically studied from the perturbation formulas of the g factors for a 3d7 ion of low spin (S = 1/2) in tetragonally elongated octahedra. In these formulas, the contributions to the g factors from the tetragonal distortion, characterized by the tetragonal field parameters Ds and Dt are taken into account. According to the calculations, the ligand octahedra around Ni3+ are suggested to suffer 2% relative elongation along the [001] (or C4) axis due to the Jahn-Teller effect.

关键词: defect structures;electron paramagnetic resonance;crystal-fields and;spin Hamiltonians;Ni3+;LaAlO3;LaYAlO3;YAlO3;atomic screening constants;optical-spectra;paramagnetic-resonance;superconducting tapes;lattice-distortions;superposition model;scf;functions;cr3+ ions;crystals;epr

非微扰QCD和核遮蔽效应对K因子的影响

智海素 , 侯召宇

原子核物理评论 doi:10.3969/j.issn.1007-4627.2006.01.002

考虑非微扰量子色动力学物理真空夸克凝聚效应,计算了碳核与碳核在质心系能量分别为630和200 GeV时碰撞Drell-Yan过程的K因子,以及加入核遮蔽因子后非微扰效应对K因子的影响,并把计算结果与没有考虑夸克凝聚非微扰效应的K值进行了对比.结果表明,非微扰效应和核遮蔽效应对K因子影响很小.

关键词: K因子 , Drell-Yan过程 , 夸克凝聚 , 非微扰量子色动力学 , 核遮蔽效应

不同共聚体系对丙烯腈与丙烯酸单体竞聚率的影响

陈厚 , 刘军深 , 曲荣君 , 纪春暖 , 王成国 , 蔡华甦

高分子材料科学与工程

采用Kelen-Tudos方法, 测定了丙烯腈(AN)与丙烯酸(AA)共聚合反应体系中单体竞聚率,探讨了不同反应体系对单体竞聚率的影响.结果表明,在水相悬浮聚合体系中,当转化率小于20%时,两单体的竞聚率同DMSO均相溶液聚合结果相近;随转化率的增加,AN竞聚率增加,AA竞聚率减小,当转化率超过50%后,两单体竞聚率变化不明显.在H2O/DMSO混合溶剂沉淀聚合中,当水含量超过80%后,两单体竞聚率向水相悬浮聚合结果靠近.随溶剂极性增大,rAN与rAA值均减小.

关键词: 共聚反应 , 动力学 , 竞聚率

充填管道布置方案优化中的数值模拟分析

羊羽翔 , 付建新 , 宋卫东

黄金 doi:10.11792/hj20140808

矿山在充填管道布置方案中参数的选取往往通过经验公式估算，而目前尚无精确解的计算方法。但参数的选取恰当与否直接影响到矿山充填系统的效率以及使用寿命，因此参数选取的精确化便显得尤为重要。以石人沟铁矿的充填系统为工程背景，应用ANSYS分析软件中的FLOT-RAN CFD模块建立管道模型，分析了管道系统采用不同充填倍线时流速与压力的关系，并据此对充填倍线的理想值进行了分析计算，最终得出充填倍线为3．5，符合经验值的取值范围，对矿山充填管道布置方案有一定借鉴意义。

关键词: FLOTRAN CFD模块 , 充填倍线 , 管道模型 , FLUD141单元 , 方案优化

Effects of preparation technology on the structure and amorphous forming region for electroless Ni-P alloys

Journal of Materials Processing Technology

This paper has studied systematically the preparation technology and its effects on the structure and amorphous forming region (AFR), and theoretical description of the AFR for electroless Ni-P alloys. It has been found that the deposition rates increase and approach a maximum value and then decrease with the increase in the concentration of nickel chloride, sodium hypophosphite and pH value, respectively. However, the deposition rates decrease with the increase in sodium citrate. The AFR is P > 9-10 at.% in the range of concentration of nickel chloride studied. In the ran-e of concentration of sodium hypophosphite studied, there was no crystalline structure observed. The AFR calculated theoretically using the Miedema model was in good agreement with the experimental results. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词: electroless Ni-P alloys;preparation technology;structure;amorphous;forming region;Miedema model;formation enthalpies;nickel deposition;mechanism

Thermodynamic predictions of Mg-Al-Ca alloy compositions amenable to semi-solid forming

International Journal of Materials Research

Thermodynamic prediction based oil a two-stage simulation has been carried out to investigate the composition range of Mg-Al-Ca alloys amenable to semi-solid forming. The results show that increasing the solute elements decreases the temperature sensitivity, but their effects oil the solidification ran-e are greatly different. In some Mg-Al-Ca alloys, the highest knee point in the liquid fraction vs. temperature Curve IS generated by the formation of Al(2)Ca phase. Several critical sections of the Mg-Al-Ca ternary system are also given. The criteria for semi-solid formability are identified and a range of compositions for Mg-Al-Ca alloys are evaluated in relation to these criteria. By comparing with A356 alloy and AZ91 alloy, a typical Mg-Al-Ca alloy AC74. is predicted to exhibit good semi-solid formability comparable to A356 and much better than AZ91.

关键词: M-Al-Ca magnesium alloy;Thermodynamic prediction;Alloy composition;selection;Semi-solid forming;az91d magnesium alloy;mechanical-properties;phase-equilibria;earth-elements;creep-behavior;zn alloys;microstructure;system;state

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