SiC/C界面辐照性能的分子动力学研究

本文通过分子动力学模拟的方法,研究了5种含不同空间结构的SiC/C界面的材料受辐照后的缺陷分布随时间以及PKA位置的变化关系,并与单质SiC中缺陷分布情况进行对比.利用径向分布函数分析了辐照对界面原子排列情况的影响.研究结果表明,SiC/C界面的抗辐照能力明显低于SiC内部,不同的空间结构对界面缺陷数量存在一定影响.由径向分布函数推得界面区域石墨原子密度高则界面原子排列情况受辐照影响越大.     

蒙脱土纳米片增强的仿生结构强韧水凝胶薄膜

传统单网络水凝胶力学性能差,难以作为对力学强度和综合性能方面有高要求的硬脑膜修复材料使用。提高水凝胶的力学性能对于水凝胶的应用具有重要意义。本文通过蒸发诱导组装方法制备了聚乙烯醇/蒙脱土（PVA/MMT）水凝胶薄膜,该水凝胶薄膜具有优异的机械性能和抗疲劳性能。所制备的PVA/MMT水凝胶薄膜厚度为200 - 300 μm之间,断裂应力为9.5 ± 0.2 MPa、模量为9.0 ± 0.9 MPa、疲劳强度为1154.02 J?m-2,性能优于现有的生物聚合物水凝胶。加入蒙脱土（MMT）后,PVA/MMT水凝胶薄膜的机械性能得到提升。这得益于MMT在PVA/MMT水凝胶薄膜中形成有序的层状结构。PVA70/MMT30水凝胶薄膜借助戊二醛交联后,PVA和MMT之间形成C-O-C共价键,促使薄膜的机械性能进一步提高。     

Integrated a-Si：B Microbolometer Arrays Based on Improved Porous Silicon Micromachining Techniques

A monolithic uncooled 8 × 8 microbolometer array with is presented. The a-Si：B film was deposited by plasma boron-doped a-Si （a-Si：B） thermistors as active elements enhanced chemical vapour deposition. To decrease the thermal conductance of the microbolometer, a-Si：B thermistor was formed on a four-leg suspended microbridge. The improved porous silicon micromachining techniques described here enable the integration of the sensor array with the metal oxide-semiconductor readout circuitry. The sacrificial material of porous silicon is prepared in the first step. It is then well protected all the time during the fabrication of metal-oxide-semiconductor field effect transistors and microbolometers before being released. Measurements and calculations show that the uncorrected uniformity of the 8 × 8 microbolometer array is about 4.5%, and the detectivity of 2.17 × 10^8 cm Hz^1/^2W^-1 is achieved at a chopping frequency of 30 Hz and a bias voltage of 5 V with a thermal response time of 12.4 ms.