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Accurate measurement of strain is one of the most important issues for high temperature environments. We present a highly integrated all-fiber sensor to achieve precise measurements of strain/high-pressure, which consists of a fiber Bragg grating (FBG) inscribed by an 800 nm femtosecond laser cascaded with a micro extrinsic Fabry–Perot (FP) cavity fabricated by the 157 nm laser micromachining technique. FBG is sensitive to temperature, but insensitive to strain/pressure, whereas the FP is sensitive to strain/pressure, but has a small dependence on temperature. Therefore, such a cascaded sensor could be used for dual-parameter measurement and can work well at high temperatures. Experimental results indicate that this device exhibits a good strain characteristic at high temperatures and excellent high-pressure performance at room temperature. Due to its highly sensitive wavelength response, the proposed sensor will have remarkable potential applications in dual parameter sensing in harsh environments.

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In this paper, pure silk protein was extracted from Bombyx mori silks and fabricated into a new kind of disordered bio-microfiber structure using electrospinning technology. Coherent random lasing emission with low threshold was achieved in the silk fibroin fibers. The random lasing emission wavelength can be tuned in the range of 33 nm by controlling the pump location with different scattering strengths. Therefore, the bio-microfiber random lasers can be a wide spectral light source when the system is doped with a gain or energy transfer medium with a large fluorescence emission band. Application of the random lasers of the bio-microfibers as a low-coherence light source in speckle-free imaging had also been studied.

A nanocrystalline-amorphous (NC-A) mixed layer was obtained by ultrasonic shot peening (USP) on pure titanium at room temperature and observed by X-ray diffraction pattern (XRD), scanning electron microscope (SEM) and high-resolution transmission electron microscope (HRTEM). The results showed that the amorphization percentage in the NC-A mixed layer increased continuously with the increase of the peening duration, shot diameter and sonotrode amplitude or the decrease of the peening distance. The maximum amorphization percentage achieved in this study was 44.09%. Moreover, with the amorphization percentage in the NC-A mixed layer increasing, the surface hardness increased constantly. Base on the experimental results, the amorphization mechanism during USP treatment was also analyzed.