With the rapid development of modern industries, the high-temperature piezoelectric sensors that can work in extreme environments are in great demand. In this work, langasite (La₃Ga₅SiO14, LGS), as a high-temperature piezoelectric crystal with stable electro-elastic performance, is used as core element, and air and porous Al₂O₃ are selected as backing layers respectively to prepare two kinds of high-temperature acoustic emission (AE) sensors. The detection sensitivities at 25–500^∘C are analyzed by the ball falling test and Hsu–Nielsen experiment. Under the condition of 25–500^∘C, the received amplitude signals by both sensors are maintained above 90dB stimulated by the ZrO₂ ceramic ball dropping. In the Hsu–Nielsen experiment, as the temperature rising from 25^∘C to 500^∘C, the signal amplitude of sensor with air backing layer decays from 447mV to 365mV, while the signal amplitude varies from 270mV to 203mV for the sensor with porous Al₂O₃ backing layer. Significantly, compared with the bandwidth of the air-backing sensor (37–183kHz), the sensor with porous Al₂O₃ backing layer broadens bandwidth to 28–273kHz. These results show that both these AE sensors have strong and stable response ability to AE signals at high-temperature of 500^∘C. Therefore, piezoelectric AE sensor based on LGS has great potential application in the field of high-temperature structural health monitoring.

针对离轴光学系统装调过程中自由度高且互相耦合的问题，提出一种新的离轴自由曲面反射式光学系统装调方法，采用计算全息图（CGH）实现多镜共基准定姿定态，解耦合系统各镜片的装调自由度，显著降低系统装调复杂度；分析CGH用于定姿定态时的定位精度，提高系统装调精度和效率，适应不同构型的离轴光学系统。利用上述方法，完成口径为210mm、视场为2°×2°的近红外长波红外双波段离轴反射式光学系统装调，全视场波像差RMS小于0.126λ（λ=632.8nm），达到设计预期，装配周期短，成像质量优良。

研制高性能隔热材料对发展航空、建筑、运输等领域具有重要意义。二氧化硅(SiO2)纤维具有低密度、低热导、抗氧化的优点, 是一种极具发展潜力的隔热材料。然而, SiO2纤维的热导率有待进一步降低, 如何进一步提升其隔热性能是一个重要课题。本文从SiO2纤维的隔热机理出发, 首先分析了不同形貌(实心、中空、多孔)SiO2纤维的制备方法及研究现状, 并总结了SiO2纤维与有机材料、无机材料等复合的研究进展。同时, 简述了隔热材料目前的主要应用领域, 最后展望了SiO2纤维基隔热材料在未来的发展方向。

近年来，为了使加工技术更加精准、无误差，各国研究者投入到了微加工领域的研究。而飞秒激光以其极高的峰值、较小的损伤阈值、高的聚焦力，使其成为国内外在微加工领域的热点研究对象。总结了近年来飞秒激光在微加工领域的研究进展，并从微加工金属材料、集成光学、生物医疗、纳米加工领域进行综述，最后指出飞秒激光发展到现在所存在的问题及对未来的期想。