材料期刊网

Study of Sintering Behavior and Electrical Conductivity of Cr-Zn-Fe-O System

A.A.Hanna , M.Sh.Khalil , H.I.Saleh , A.F.Ali

材料科学技术（英文）

A series of chemical compositions based on Cr, Fe and O with Zn as a partially substituting ion has been prepared in the general formula ZnxCr1-xFe2O by coprecipitation method using NH4OH as the precipitating agent at pH=10.3. The prepared samples were identified by both thermal analysis (DTA and TGA) and X-ray diffraction (XRD). It was found that no single phase was obtained for any of the studied compositions but a mixture of different phases was observed, depending on the molar percentage of zinc ion substitution as well as on the sintering temperature. The temperature dependence of the electrical conductivity, σ, of the prepared samples was plotted between 25 and 680℃. It was observed that the electrical conductivity increased with temperature for both samples with x=0.00 and 0.80 Zn ion content while it was nearly temperature independent for samples with intermediate Zn concentration x=0.2 and 0.5 mol fraction. The activation energy, Ea, calculated from the linear relation, lgσ-1000/T for the final mixtures (sintered at 1300℃) was calculated.

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Electrical conductivity and infra red of CaTiO3 doped with CuO

F.F.Hammad , M.Sh.Khalil , A. H. Salama

材料科学技术（英文）

The electrical conductivity of pure CaTiO3 and that containing 0.5 similar to5.0 mole fraction CuO as dopant were measured in the temperature range 291 similar to 773 K. The conductivity values varied as a function of temperature and dopant concentration. The activation energy in the lower temperature range depended on the impurity content while in the high temperature range it indicated a value of energy gap width. The infrared absorption spectra in the range of 100 similar to 4000 cm(-1) revealed the presence of two main bands at 340 and 570 cm(-1) which were assigned to TiO6 octahedral normal mode. Bands in the range of 106 similar to 270 cm(-1) were due to the vibration of anion TiO3-2. Some bands were observed at higher values due to the presence of lattice imperfections. There was a slight shift in band position with increasing dopant concentration which favors the formation of orthorhombic modification.

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压电复合材料层合结构中的SH波

代海涛 , 程伟

复合材料学报 doi:10.3321/j.issn:1000-3851.2007.01.030

考虑压电耦合效应,通过传递矩阵-二维谱分析研究了压电复合材料层合板稳态SH波的频散特性和瞬态SH波的传播特性.数值分析表明: 压电耦合作用提高了SH波的截止频率和相速度;由表面扰动激发的SH波,一部分能量向板深度方向传播,一部分以表面波的形式在两倍波长深度内传播.所采用的传递矩阵-二维谱分析为层合结构瞬态波动研究提供了一种有效的数值方法.

关键词: SH波 , 压电效应 , 频散关系 , 传递矩阵 , 二维谱 , 表面波

共混膜SH/KGM作为防止瘢痕粘连材料的体外实验研究

朱向情 , 陈强 , 庞荣清 , 陈翠竹 , 王强 , 陈佳 , 陈庆华 , 潘兴华

材料导报 doi:10.11896/j.issn.1005-023X.2014.22.012

利用透明质酸钠(Sodium hyaluronate,简称SH)和魔芋葡甘聚糖(Konjac glucomannan,简称KGM)制备共混膜SH/KGM,通过膜的干预减少或阻止硬膜外瘢痕的形成.选择人皮肤成纤维细胞为种子细胞,采用流式细胞术和半定量PCR方法检测细胞的纯度;通过体外移植的方法将成纤维细胞移植到SH/KGM共混膜表面,细胞形态学观察发现细胞由原来的梭形变成不规则的圆形,且细胞能够粘附于SH/KGM共混膜的表面,但移植细胞在移植后的2天、5天和7天内均没有观察到增殖.这种现象表明共混膜SH/KGM具有防止硬膜外瘢痕粘连的作用,可以作为腰椎手术的介入材料.

关键词: 皮肤成纤维细胞 , 透明质酸钠 , 魔芋葡甘聚糖 , 共混膜 , 瘢痕

基于SH1123驱动器的OLED接口及驱动程序设计

丁卫撑 , 王义 , 李元景 , 王敏 , 方方

液晶与显示 doi:10.3969/j.issn.1007-2780.2009.06.024

介绍了基于SH1123驱动器的OLED点阵图形显示模块,给出了模块与微处理器C8051F340的硬件接口电路,简要分析了SH1123的指令系统,对C语言编程环境下模块底层驱动程序的实现进行了重点阐述,并给出如何利用按键实现显示菜单控制的方法.

关键词: 微处理器 , 接口 , 驱动程序 , OLED显示

船用高强钢SH01焊条冷裂纹敏感性研究

周红兵 , 吴松林 , 王任甫 , 薛钢

材料开发与应用

采用插销试验和扩散氢试验研究了不同温湿度下的冷却速度、扩散氢含量对SH01焊条冷裂纹敏感性的影响,用扫描电镜观察了插销断口形貌.结果表明,SH01焊条的冷裂纹敏感性较低,其最小临界断裂应力Rcr为830MPa,大于焊条熔敷屈服强度Rp0.2;断口除起裂区具有沿晶和准解理的脆性特征外,其余为韧性的韧窝特征.

关键词: 插销试验 , 扩散氢 , 冷裂纹 , SH01焊条

Theoretical studies on the SH parameters and local distortion structure of KCl:Ag(2+) crystal

Physica B-Condensed Matter

Complete diagonalization of the energy matrix and high order perturbation formulae of spin-Hamiltonian (SH) parameters possessing D(4h) symmetry for the 4d(9) ion based on the crystal- and ligand-field theory in tetragonal symmetry are expressed and applied to the study of local distortion structure of the KCl:Ag(2+) crystal. The calculated results agree well with experimental findings. Both complete diagonalization of energy matrix and high order perturbation approach are appropriate for the investigations of SH parameters of 4d9 ions in tetragonal crystals. Tetragonal distortion due to the Jahn-Teller effect for the tetragonal Ag(2+) center at the K(+) site of KCl crystal is also acquired from the calculations. (C) 2010 Elsevier B.V. All rights reserved.

关键词: Crystal- and ligand-field theory;Spin-Hamiltonian (SH) parameters;Distortion structure;Ag(2+);KCl;spin-hamiltonian parameters;atomic screening constants;single-crystals;paramagnetic-resonance;epr parameters;scf functions;ions;spectra;field;temperature

SH波对圆形夹杂与裂纹的散射及其动应力集中

史守峡 , 杨庆山 , 刘殿魁 , 齐辉

复合材料学报 doi:10.3321/j.issn:1000-3851.2000.03.024

采用Green函数的方法,研究了介质中同时存在夹杂与裂纹时对SH波的散射,构造了在含有半圆形夹杂的弹性半空间,水平面上任一点承受时间谐和出平面线源载荷作用时的位移函数作为Green函数.并推导了SH波对夹杂与裂纹散射的定解积分方程组,进而求得裂纹尖端的动应力因子.重点讨论了夹杂的存在对裂纹尖端动应力因子的影响,给出了随夹杂介质参数及夹杂与裂纹距离对裂纹尖端动应力因子的分布曲线,为工程设计提供参考依据.

关键词: SH波 , 夹杂 , Green函数 , 动应力集中因子

固-固结构声子晶体中SH波的色散关系及其全反射隧穿

刘启能 , 刘沁

材料导报

利用边界条件推导出SH波在多层介质系统中的转移矩阵,得出了SH波在一维固-固结构声子晶体中的色散函数.利用色散函数研究了SH波在一维固-固结构声子晶体中的全反射隧穿效应,得出SH波的全反射隧穿导带的特征:全反射隧穿导带的频率中心随入射角的增加而向高频方向移动,全反射隧穿导带的频率宽度随入射角的增加而减小；全反射隧穿导带的频率中心和频率宽度都随周期厚度的增加而减小.

关键词: 声子晶体 , SH波 , 色散 , 全反射

蒙脱石-OR-SH复合材料修复镉污染土壤的环境风险及时效性评价?

赵秋香 , 刘文华 , 冯超 , 江海燕 , 李锡坤

环境化学 doi:10.7524/j.issn.0254-6108.2015.02.2014060301

以钙基蒙脱石原材料为空白对照，通过细胞活性实验和小鼠急性毒性实验对制备的土壤重金属钝化剂蒙脱石?OR?SH复合材料进行环境风险评价，结果显示，在受试样品浸出物浓度为8 mg／100 mL及以下时，蒙脱石?OR?SH及饱和吸附Cd的蒙脱石?OR?SH对K562细胞、人脐带间充质干细胞和人肝细胞的活性无显著性影响；小鼠毒性实验结果显示，其毒性分级1级，实际无毒性作用。蒙脱石?OR?SH修复Cd污染土壤的长效性盆栽研究显示，第一季的钝化效果显著，虽然之后效果依次递减，但在连续种植了四季盆栽后，蒙脱石?OR?SH对土壤中的Cd仍保持显著的钝化效果。

关键词: 蒙脱石-OR-SH复合材料 , 镉 , 风险 , 时效性