Al2O3-CeO2复合电解质的制备及其半导体离子燃料电池性能

通过共沉淀法制备了Al₂O₃-CeO₂复合材料,并将其作为电解质应用于半导体离子燃料电池（SIFC）。探究了Al₂O₃、CeO₂物质的量之比不同的Al₂O₃-CeO₂复合电解质对SIFC电化学性能的影响。采用X射线衍射（XRD）、X射线光电子能谱（XPS）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）对材料进行了表征。其中,Al₂O₃、CeO₂物质的量之比为1：0.5的Al₂O₃-CeO₂（1：0.5）电池获得了最佳性能,在550℃下,开路电压为1.099 V时最大功率密度为1 142 mW·cm^-2。得益于复合电解质在测试气氛下两相间的界面效应,Al₂O₃-CeO₂（1：0.5）电池在较低测试温度下取得了优异的混合离子传导和功率输出性能。     

Ag2V4O11纳米线的制备及光吸收性能研究

以Ag20和V2O5为原料,采用水热法合成了Ag2V4011纳米线.采用X射线衍射(XRD)和场发射扫描电子显微镜(FE-SEM)对样品的结构及形貌进行了表征,并采用紫外-可见光吸收法(UV-vis)测定了样品的光吸收性能.紫外-可见光吸收测试显示AB2V4O11纳米线具有较宽的紫外-可见光吸收范围,通过计算得出Ag2V4O11-纳米线的光学带隙为1.77eV.     

基于粗糙集的指标体系优化及评价方法研究

粗糙集方法能客观、有效地对有限指标数据进行挖掘,通过属性约简剔除冗余指标,并根据属性重要度生成指标权重,系统地探讨了利用粗糙集进行指标体系优化和综合评价的全过程思路及方法,并通过同行评议专家科技信用评价实例,验证了方法的实用性.     

铁电阴极电子枪的初步实验研究

 设计加工了铁电阴极电子枪,给出了模拟计算及其初步实验结果。电子枪为皮尔斯枪型,采用顺电相陶瓷Ba0.67Sr0.33TiO₂作为铁电阴极材料,电子枪电压脉宽80 ns,幅值最大可达80 kV,设计电子枪导流系数为0.15×10^-6 A·V^-3/2。电子枪电压从30 kV逐步增大到56 kV,测量到其发射电流从0.7 A逐步增大到2.5 A。根据实验结果拟合得到的电子枪导流系数为0.2×10^-6 A·V^-3/2,与设计基本符合。     

Fractal Analysis of Power-Law Fluid in a Single Capillary

The fractai expressions for flow rate and hydraulic conductivity for power-law fluids in a single capillary are derived based on the fractai nature of tortuous capillaries. Every parameter in the proposed expressions has clear physical meaning. The flow rate and hydraulic conductivity for power-law fluids are found to be related to the tortuosity fractal dimension and the power-law index. The flow rate for power-law fluids increases with the increasing power-law index but decreases with the increasing tortuosity fractal dimension. Good agreement between the model predictions for flow in a fractai capillary and in a converging-diverging duct is obtained. The results suggest that the fractal capillary model can be used to model the power-law fluids with different rheologicai properties.     

Adsorption and Reaction of CO on （100） Surface of SrTiO3 by Density Function Theory Calculation

Adsorption and reaction of CO on two possible terminations of SrTiO3 （100） surface are investigated by the first-principles calculation of plane wave ultrasoft pseudopotentiai based on the density function theory. The adsorption energy, Mulliken population analysis, density of states （DOS） and electronic density difference of CO on SrTiO3 （100） surface, which have never been investigated before as far as we know are performed. The calculated results reveal that the Ti-CO orientation is the most stable configuration and the adsorption energy （0.449eV） is quite small. CO molecules adsorb weakly on the SrTiO3 （100） surface, there is predominantly electrostatic attraction between CO and the surface rather than a chemical bonding mechanism.     

First-Principles Calculation of Electronic Structure and Optical Properties of Sb-Doped ZnO

The geometric structure, electronic structure, optical properties and the formation energy of Sb-doped ZnO with the wurtzite structure are investigated using the first-principles ultra-soft pseudo-potential approach of plane wave based upon the density functional theory. The calculated results indicate that the volume of ZnO doped with Sb becomes larger, and the doping system yields the lowest formation energy of Sb on the interstitial site and the oxygen site. Furthermore, Sb dopant first occupies the octahedral oxygen sites of the wurtzite structure. It is found that Sb substituting on oxygen site behaves as a deep acceptor and shows the p-type degenerate semiconductor character. After doping, the electron density difference demonstrates the considerable electron charge density redistribution, which induces the effect of Sb-doped ZnO to increase the charge overlap between atoms. The density of states move towards lower energy and the optical band gap is broadened. Our culated results are in agreement with other experimental results and could make more precise monitoring and controlling possible during the growth of ZnO p-type materials.     

网纹型表面微结构对Ti-6Al-4V水润滑摩擦学特性的影响

研究了Ti-6Al-4V合金表面网纹型微结构与Si3N4小球对摩时的水润滑摩擦学性能.利用电火花加工技术在Ti-6Al-4V合金表面加工出不同尺寸的网纹结构,运用正交试验设计方法分析了网纹宽度、深度、间宽比和网纹角度对Ti-6Al-4V合金水润滑摩擦学性能的影响.结果表明:具有合适几何参数的网纹结构能够降低摩擦副在水润滑条件下的摩擦系数和磨损量.当网纹角度在45°时,摩擦副的摩擦系数和磨损量能同时降低.网纹宽度对稳态摩擦系数的影响最大,而网纹深度和夹角对摩擦副材料的磨损影响最大.     

用可调探深的电子能量损失谱研究Sn/Si界面

用可调探测深度的电子能量损失谱辅以俄歇电子能谱和低能电子衍射,研究Sn/Si系统的界面反应。结果表明:当Sn蒸镀量大于两个原子单层,退火温度由400℃到700℃,在Sn/Si(111)界面Sn与Si发生互混,形成几个原子层厚的Sn/Si互混层,该互混层的特征体峰在15.5eV。在相同温度范围退火,Sn/Si(001)界面无可察觉的互混,仍有Sn岛存在,长时间在550℃退火低能电子衍射图形上出现(113)小晶面的衍射斑。 关键词：     

激光光切法测量不规则堆料的截面面积

在分析现有各种三维测量方法的基础上,提出了基于光切图像扫描法的三维测量方法。该方法通过扫描移动堆料,获取堆料上一系列平行截面的轮廓线,并计算出截面面积,然后根据各截面面积和扫描间距解算出物体体积。在此基础上,设计完成了实验检测装置,开发了处理与测量软件。对不同形状的物体进行了多次实验测试,验证了测量方法的可行性和重复性。