ELECTRORHEOLOGICAL PROPERTIES OF POLYANILINE/PUMICE COMPOSITE SUSPENSIONS

Electrorheological （ER） properties of polyaniline （PAni）, pumice and polyaniline/pumice composites （PAPC） were investigated. Polyaniline and PAni/pumice composite were prepared by oxidative polymerization. PAni/pumice particlesbased ER suspensions were prepared in silicone oil （SO）, and their ER behavior was investigated as a function of shear rate, electric field strength, concentration and temperature. Sedimentation stabilities of suspensions were determined. It has been found that ER activity of all the suspensions increases with increasing electric field strength, concentration and decreasing shear rate. It has shown that the suspensions have a typical shear thinning non-Newtonian viscoelastic behavior. Yield stress of composite suspensions increased linearly with increasing applied electric field strength and with concentrations of the particles. The effect of high temperature on ER activity of purrfice/silicone oil systems was also investigated.     

同多酸和杂多酸修饰微电极的电化学研究 Ⅶ.磷钒钼杂多酸薄膜修饰微电极和杂多酸/聚苯胺薄膜修饰微电极的制备和电化学性质

本文详细描述了磷钒钼杂多酸（PV2Mo10）极薄膜修饰碳纤维（CF）微电极和PV2Mo10／聚苯胶（PAn）薄膜修饰微电极的制备及其电化学性质。     

聚苯胺修饰电极上抗坏血酸与多巴安胺氧化峰的分离

本文介绍了一种分离抗坏血酸（ＡＡ）和多巴胺（ＤＡ）氧化峰的新方法。聚苯胺（ＰＡ）ＡＡ和ＤＡ有不同的催化性。因而在ＰＡ修饰电极上，ＡＡ和ＤＡ在不同的电位被氧化，从而解决了二者氧化峰不能分离的问题。实验表明，在ＰＡ膜电极上，ＡＡ和ＤＡ氧化峰可分开约１４０ｍＶ。     

碳化硼纳米线的制备和结构

以碳纳米管为模板，通过加热碳纳米管与硼粉的混合物，获得了笔直的硼碳纳米线.对纳米线的结构和成分进行研究，结果表明纳米线主要为B4C纳米线.在部分B4C纳米线的端部存在Ni颗粒，这些端部具有Ni颗粒的纳米线构成了纳米磁针.讨论了B4C纳米线的生长机制，B4C纳米线的生长主要为硼原子在碳纳米管中扩散并发生化学反应，使得碳纳米管晶格结构发生重组，形成B4C纳米线.反应后，硼原子部分取代了碳纳米管中碳原子，修补了碳纳米管中的晶格缺陷，获得了形态笔直的B4C纳米线.     

离子液体中电沉积制备钴纳米线阵列

Porous anodic alumina (PAA) was used as a template to prepare Co nanowires array from 1-ethyl-3-methylimidazolium chloride ionic liquid by direct current method. The surface morphology of porous anodic alumina template was observed by field emission-scanning tunneling microscopy (FE-SEM) before and after the electrodeposition of Co nanowires. The electrodeposition of Co nanowires was characterized by transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). TEM results indicate that the Co nanowire surface is coarse and porous when aqueous solution was used as electrolyte， and the Co nanowire deposited from the ionic liquid is uniform and smooth. XRD results show that the electrodeposition of Co is a mixture of crystal and microcrystal phase.     

聚苯胺／聚乙烯醇导电复合膜的制备及性质研究

用较简单的化学氧化现场吸附聚合法（ｉｎ－ｓｉｔｕｐｏｌｙｍｅｒｉｚａｔｉｏｎ）制得了聚苯胺（ＰＡｎ）／聚乙烯醇（ＰＶＡ）导电复合膜．该膜具有较好的导电性和机械性能；其电导率可达５．８ｓ／ｃｍ，拉伸强度达１３ＭＰａ，断裂伸长率为１１０％左右．本文讨论了制备的各种条件对复合膜导电性能及力学性能的影响、稳定性及电化学活性；并采用循环伏安曲线、扫描电镜（ＳＥＭ）、ＦＴＩＲ谱及元素分析对该复合膜的结构和性能进行了表征．     

取向碳纳米管/硅纳米线复合阵列的制备

在阳极氧化铝模板(AAO)的取向微孔内, 利用化学气相沉积(CVD) 技术首先制备了两端开口高度取向的碳纳米管阵列, 再在碳纳米管中间的孔洞内沉积硅纳米线, 成功制备了碳纳米管/硅纳米线(CNTs/SiNWs)核鞘复合阵列结构. 用SEM, TEM, XRD等仪器分析了CNTs/SiNWs核鞘复合阵列和沉积在碳纳米管孔洞内的硅纳米线的生长特性和晶体结构, 利用I-V关系和Fowler-Nordheim方程研究了其场发射(FE)特性, 用荧光光谱分析仪分析了复合阵列的荧光(PL)特性. 证明了模板法制备的CNTs/SiNWs核鞘复合阵列结构可用来制作具有金属/半导体(M/S)特性的纳米PN结, 该复合阵列结构也使SiNWs包覆在CNTs惰性鞘内, 可防止SiNWs在空气中的进一步氧化. 制备出的CNTs/SiNWs核鞘复合阵列结构生长方向高度有序, 直径和长度易于控制, 极少产生其他制备方法中出现的纳米结构弯曲和相互缠绕现象.     

半导体所在GaAs纳米线结构相变的研究方面取得重要成果

作为传统的Ⅲ-V族半导体,GaAs体材料的稳定相是闪锌矿结构。但是当进入到纳米尺度时,由于表面积相对增加,又由于纤锌矿结构的表面能较低,使得GaAs纳米线上容易出现纤锌矿结构,互相竞争的结果往往是两相共存,还夹着很多平面缺陷(planar defect)。因此如何得到纯闪锌矿或者纯纤锌矿结构的