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In order to provide a convenient and fast calculation method, the equivalent circuit of a novel stacked piezoelectric cymbal vibrator is studied. The equivalent circuit model of the piezoelectric stack is derived by combining the equivalent circuit models of the thin piezoelectric disk and electrode. The equivalent circuit of the cymbal structure is then derived. The equivalent circuit model of the stacked piezoelectric cymbal vibrator is further proposed. The output axial displacements and output forces of the cymbal vibrator under different excitation voltages are investigated using the equivalent circuit model. The effectiveness of the equivalent circuit has been verified by comparing it with the finite element method. Furthermore, the equivalent circuit method has a much faster calculation speed than the finite element method. [ABSTRACT FROM AUTHOR]

As demand for haptic feedback increases, piezoelectric materials have become one of the best candidate materials due to their small size, high electromechanical coupling coefficient, and fast response. A stacked piezoelectric cymbal vibrator is proposed based on the common cymbal-type transducer, which is composed of a piezoelectric stack to drive and a cymbal disk to amplify displacement. A coupling theoretical model between the piezoelectric stack and the cymbal-type structure is established. The longitudinal and radial displacements of the stacked piezoelectric cymbal vibrator are calculated in the low frequency range (<1000 Hz) by the theoretical model and the finite element method. The theoretical and numerical results are in good agreement. The results show that the radial displacement can be converted into longitudinal displacement and then effectively amplified by the cymbal disk with an amplification ratio of 30. The feature is conducive to its widespread application in the field of consumer electronics. [ABSTRACT FROM AUTHOR]

Soy protein isolated (SPI) have a wide application in the food packaging, but their water resistance, mechanical properties and antibacterial properties are not ideal for directly use. In our study, we developed a series of SPI composite films loaded with cinnamaldehyde and titanium dioxide (TiO2). X‐ray diffraction (XRD), UV scanning spectra (UV) and spectro colorimeter were applied to indicate the structure of films. The incorporation of TiO2 (0.5%) caused a subsequent effect on the tensile property, UV blocking properties and water vapor properties (WVP). On the other hand, SPI film composed with a constant amount of TiO2 and different concentration of cinnamaldehyde showed an excellent synergistic effect to improve the tensile property, moisture content, UV blocking properties, water vapor properties and morphological characteristics. Furthermore, the composite films exhibited superior antibacterial activity when tested against both S. aureus and E. coli. The microstructure of the composite film become heterogeneous and rough after addition of TiO2 and cinnamaldehyde compare to control film. The findings of the present study may facilitate a re‐evaluation of the potential of using multiple compounds to prepare active edible films. [ABSTRACT FROM AUTHOR]