Nd掺杂的Bi4Ti3O12变温X射线衍射分析

利用变温X射线衍射技术，在预烧过程中分析了Nd掺杂Bi4Ti3O12后生成Bi3.15Nd0.85Ti3O12（BNT）相的形成过程以及微结构的变化．实验观察到以30℃／min的升温速率，BNT相在700℃时开始形成，其衍射峰强度随温度的继续升高而增强，衍射峰半高宽随烧结时间延长而减小．X射线衍射分析结果表明，在900℃恒温条件下，烧结约2h，可形成单一的BNT相．     

脉冲激光沉积BNT和KNN系陶瓷薄膜的比较研究

利用脉冲激光沉积技术(PLD),在不同的制备工艺条件下,分别在Pt/Ti/SiO2/Si基片上制备了Bi0.5Na0.5TiO3(BNT)系列的Bi0.5(Na0.7K0.2Li0.1)0.5TiO3(BNKLT)和K0.5Na0.5NbO3(KNN)系列的Li0.04(Na0.5K0.5)0.96(Nb0.775Ta0.225)O3(KNNLT)无铅压电陶瓷薄膜,并利用X射线衍射仪(XRD)、扫描电镜(SEM)和原子力显微镜(AFM)对薄膜的晶体结构及表面形貌进行了比较研究.研究结果表明:薄膜的衬底温度、沉积室的氧气压力和薄膜的热处理温度对BNT和KNN薄膜结构和形貌都有较大影响,且影响程度不同;在最佳制备工艺参数下,利用PLD制备的BNT和KNN无铅压电陶瓷薄膜都具有精细的表面结构.     

Electronic transport properties of single-wall boron nanotubes

Electronic transport properties of single-wall boron nanotube(BNT) with different chiralities, diameters, some of which are encapsulated with silicon, germanium, and boron nanowires are theoretically studied. The results indicate that the zigzag(3, 3) BNT has more electronic transmission channels than the armchair(5, 0) BNT because of its unique structure distortion. Nanowires encapsulated in the BNT can enhance the conductance of the BNT to some extent by providing a significant electronic transmission channel to the BNT. The effect of the structure of nanowires and the diameter of BNTs on the transport properties has also been discussed. The results of this paper can enrich the knowledge of the electron transport of the BNT and provide theoretical guidance for subsequent experimental study.     

无铅高居里点PTC材料的制备与性能表征

为实现电子产品无铅化要求,掺杂预先合成的BNT和其它添加剂,制备出居里温度高于130℃的钛酸钡基无铅PTC材料。对其微观组织及性能进行了测试和表征,并对添加剂、试验工艺等影响因素进行了分析。     

钛酸铋钠无铅压电陶瓷的研究进展

本文简要介绍了研究无铅压电陶瓷材料的必要性,从Bi_0.5Na_0.5TiO₃压电陶瓷材料的结构、改进机理、剩余极化强度、矫顽场和制备工艺等角度出发,论述了Bi_0.5Na_0.5TiO₃无铅压电陶瓷材料的不足和亟待解决的基本问题。综述了Bi_0.5Na_0.5TiO₃无铅压电陶瓷研究的新方法和新工艺,即改进Bi_0.5Na_0.5TiO₃的一些最新理论设想、实验成果和工艺步骤,以企本文对国内外相关研究者有所裨益。