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The thermal vibration characteristics of fiber-reinforced composite (FRC) cylindrical thin shells (FRCCTSs) coated with functionally graded porous graphene platelet (FGPGP) are investigated in this work, which is based on a theoretical model constructed by a mixed analytical and finite element method. Firstly, the porosity distributions of the FGPGP coating are assumed to be uniform or nonuniform along thickness direction with four porous forms of coating being taken into account. Next, the displacement field functions along with the axial, circumferential, and transverse directions are assumed on the basis of Love’s first-order approximation theory. Furthermore, this coated thin shell is discretized by the four-node shell element method to calculate the mass and stiffness matrices, with the artificial spring technology being adopted to simulate arbitrary boundary conditions. After the frequency parameters and dynamic responses are successfully solved, the proposed model with and without coating material is roughly validated by comparing with literature results at different boundary conditions without considering the temperature effect. Meanwhile, by utilizing the natural frequencies and vibration responses measured via a thermal vibration experiment bench, the comprehensive verification is performed within a temperature range of 20–200∘C. Finally, parametric studies are undertaken to study the influences of boundary condition, porosity distribution of coating, fiber layup pattern, the predefined thickness ratio, and elastic modulus ratio on the corresponding thermal vibration properties.

This research reports a portable immunochip, based on quartz crystal microbalance (QCM) for label-free, low-cost qualitative detection of zearalenone (ZEN) in food samples. The experimental parameters in the functionalization and working process were evaluated in detail, in order to achieve a high accuracy and sensitivity. Under optimal conditions, the ZEN concentration at an inhibition ratio of 50% and 15% of the proposed QCM immunochip achieved 3.41 µg L−1 and 0.37 µg L−1, respectively. This portable QCM immunochip also exhibited high specificity, no obvious cross-reaction to five structural analogs of ZEN, and showed other mycotoxins. It could finish the whole qualitative measurement within 30 min, showed good stability during the processes of preparation (SD &lt, 5%, n = 9), storage (frequency response &gt, 90%, in PBS at 4 °C for 15 days), and application (frequency response &gt, 90% after being reused 6 times). The developed QCM immunochip obtained accurate and repeatable recovery results in ZEN analysis in the chosen food samples (corn, wheat flour, soy sauce, and milk), which had a high correlation (R2 = 0.9844) with that achieved by the HPLC–MS/MS method. In short, this work developed a portable, stable, and reproducible QCM immunochip that could be used for rapid, low-cost, and sensitively measurement of ZEN content in real food samples.