铁酸镍纳米微粒的固相合成及其催化性能

微波辐射;乙苯脱氢;铁酸镍纳米微粒的固相合成及其催化性能     

Anti-Reflective Coatings for CRTs by Sol-Gel Process

Two types of anti-reflective coatings composed of nano-particles were developed for cathode ray tubes (CRTs). The anti-reflective and anti-static coating is composed of two layers. An outer SiO₂ layer is formed over a porous inner layer composed of titanium oxynitride (TiO _x N_y), antimony-doped tin oxide (ATO) and SiO₂. To control the reflection of the film, a porous structure is formed using a mixed sol composed of TiO _x N _y -ATO particles and hydrolyzed-polymerized tetraethoxy-silane (TEOS). The resulting double layered coating is shown to consist in a nanocomposite pseudo three-layer structure. The antireflective electromagnetic-wave-shielding coating is also composed of two layers. An outer SiO₂ layer is formed over an electric-conductive inner layer composed of silver colloids, TiO _x N _y nano particles. Silver colloids are used to obtain a film having low surface resistivity and TiO _x N _y nano-particles contained in the inner layer enhance the durability of the film. To reduce the plasma-resonance absorption caused by silver colloids, silver ions are added to the outer layer solution. The silver ions diffuse into the inner layer from the outer layer when the film is cured, touch to the surface of silver colloids, suppress the silver colloid growth and reduce the specific absorption of the film. These coatings are successfully applied to the panel glass for CRTs on an industrial scale.     

纳米粉体制备过程中粒子的团聚及控制方法研究

本文综述了纳米粉体中团聚现象的早期研究与近期进展,简单地介绍了团聚的危害,详细分析了团聚体的分类及形成,并采用DLVO理论和双电层理论对团聚的机理进行了理论分析,列举了一些目前在纳米粉体制备过程中常用的控制方法,并对该研究方向的发展趋势及进一步控制纳米粒子团聚问题进行了探讨.     

利用静电聚苯乙烯纳米微粒对LiNbO3铁电畴结构的观测

利用静电聚苯乙烯纳米微粒缀饰技术,在铁电晶体铌酸锂(LiNbO3)的极性表面观察到铁电畴表面束缚电荷吸附带异性电荷纳米小球所形成的衬度图像,正负电畴衬度图像清晰稳定.这种对铁电晶体表面电畴结构进行表征的新方法不会对样品造成任何程度的损伤和破坏,操作简便易行,并具有较高的分辨率.     

a—Si3N4纳米粒子的能级结构研究

用激光化学气相沉积法制备出平均粒径为10nm的a-Si     

紫外光表面处理对ZnO纳米粒子的晶体结构与光学性质的影响

利用溶胶凝胶法制备了ZnO纳米粒子,用紫外光照射对其进行表面处理.探讨了表面处理对ZnO纳米粒子晶体结构与光学性质的影响.结果显示:在晶体结构方面,紫外光照射会降低ZnO纳米粒子的团聚现象,缩短晶格常数,使其所受应力由压缩应力释放变为伸张应力,增大表面能,使能量最佳化并稳定而导致ZnO纳米粒子形成再构.在光学性质方面,紫外光照射会使ZnO纳米粒子表面产生较多的氧空位,而氧空位又会使其表面容易吸附羟基,使得ZnO纳米粒子变得更加亲水.     

一种新型掺半导体纳米微粒光纤

将纳米技术应用于光纤技术,通过改进的化学气相沉积法(MCVD),制成了一种新型的掺半导体纳米InP微粒的新结构光纤.经测试,该光纤中掺杂InP质量分数约为0.1%,且具有良好的波导通光性能.根据扫描电镜(SEM)下观察到的光纤截面微结构形貌,通过有限元法(FEM)进行数值分析,得到该光纤的有效截面面积约为10.01 μm2,从而进一步得到该光纤的非线性系数约为10.53 W-1·km-1.证实了此种光纤较普通光纤具有较高的非线性.     

Nano particle fluidisation in model 2-D and 3-D beds using high speed X-ray imaging and microtomography

Nanoparticles and nanocomposites have become a major focus of interest in science and technology due to exceptional properties they provide. However, handling and processing of ultra-fine powders is very challenging because they are extremely cohesive. Fluidization is one of techniques available to process powders. It has become increasingly important to understand how these nanoparticles can be handled and processed to benefit from their favourable properties. A high spatial (down to 400 nm) and temporal resolution (down to 1 ms) X-ray imaging apparatus has been designed to study nanoparticles in fluidized beds under different gas flow velocities. The mean volume distribution of the nanoparticle agglomerates was determined with X-ray microtomography. The X-ray microtomography technique provides valuable in situ, non-destructive structural information on the morphological changes that take place during fluidisation of powder samples.     

流动注射化学发光法测定头孢他啶

在碱性条件下,头孢他啶对金纳米粒子催化高锰酸钾氧化鲁米诺化学发光体系的发光强度具有明显的增敏作用,基于此建立了一种测定头孢他啶的化学发光方法.在优化实验条件下,用该法测定头孢他啶的线性范围为3.0×10-5～5.0×10-2 g/L,检出限为1.0×10-5 g/L,相对标准偏差为2.0%(ρ=4.0×10-3 g/L...     

纳米颗粒对沸腾活化核心密度的影响

根据实验所得沸腾曲线,对纳米颗粒悬浮液进行稳态数值模拟,计算了不同过热度下活化核心的密度.计算结果表明一对于不同浓度的纳米颗粒悬浮液,在考虑了其物性变化对沸腾传热的影响外,颗粒的加入对活化核心密度产生的影响是主要的因素,并且影响效果随颗粒浓度的变化不呈单向趋势.