Abstract: Disclosed is a preparation method of a dual-network collagen-based supramolecular hydrogel, including: preparing a silicate nanosheet dispersion and a collagen solution separately; mixing the silicate nanosheet dispersion with the collagen solution followed by stirring to obtain a collagen-silicate nanosheet network; preparing a tannic acid solution and a polyethylene glycol solution separately; mixing the tannic acid solution with the polyethylene glycol solution to obtain a polyethylene glycol-tannic acid network; and subjecting the collagen-silicate nanosheet network and the polyethylene glycol-tannic acid network to reaction to obtain the dual-network collagen-based supramolecular hydrogel. A dual-network collagen-based supramolecular hydrogel prepared by such method is also provided.

Abstract: Disclosed a preparation method of a green, biodegradable, and multifunctional collagen-based nanocomposite film, and overcomes the problems of difficult biodegradation, poor barrier property, and single function of food packaging materials in the existing technologies. The present invention includes the following steps: adding silicate nanosheet into deionized water for ultrasonic dispersion; then adding polyphenolic acid into the mixture, wherein a mass ratio of the polyphenolic acid to the silicate nanosheet is 1:(0.2˜1); and adjusting the pH value to 3.0˜4.0 to obtain a solution A; adding collagen with a concentration of 5 g/L into an acetic acid solution, and fully dissolving the collagen to obtain a solution B; isovolumetrically mixing the solution A with the solution B, stirring at room temperature, and adjusting the pH value to 4.5˜5.5 to obtain a casting solution; and pouring the casting solution into a polytetrafluoroethylene mold, and naturally drying to obtain a nanocomposite film.

Abstract: Provided is a bulk acoustic wave resonator. The bulk acoustic wave resonator includes an upper electrode, a piezoelectric layer and a lower electrode. The piezoelectric layer is disposed between the upper electrode and the lower electrode. At least one boundary of an orthogonal projection of the piezoelectric layer on the lower electrode includes a plurality of sawtooth structures.

Abstract: Provided is a bulk acoustic wave resonator. The bulk acoustic wave resonator includes a first electrode, a piezoelectric layer and a second electrode, where the piezoelectric layer is disposed between the first electrode and the second electrode, the piezoelectric layer is provided with at least one slit, and along a direction pointing from the first electrode to the second electrode, the at least one slit penetrates through at least the piezoelectric layer.

Abstract: Disclosed a preparation method of a green, biodegradable, and multifunctional collagen-based nanocomposite film, and overcomes the problems of difficult biodegradation, poor barrier property, and single function of food packaging materials in the existing technologies. The present invention includes the following steps: adding silicate nanosheet into deionized water for ultrasonic dispersion; then adding polyphenolic acid into the mixture, wherein a mass ratio of the polyphenolic acid to the silicate nanosheet is 1:(0.2˜1); and adjusting the pH value to 3.0˜4.0 to obtain a solution A; adding collagen with a concentration of 5 g/L into an acetic acid solution, and fully dissolving the collagen to obtain a solution B; isovolumetrically mixing the solution A with the solution B, stirring at room temperature, and adjusting the pH value to 4.5˜5.5 to obtain a casting solution; and pouring the casting solution into a polytetrafluoroethylene mold, and naturally drying to obtain a nanocomposite film.