Abstract: A functionally gradient material for guided periodontal hard and soft tissue regeneration includes a 3D printed scaffold layer and an electrospun fibrous membrane layer. The content of hydroxyapatite in the 3D printed scaffold layer is higher than the content of hydroxyapatite in the electrospun fibrous membrane layer. The pore size of the 3D printed scaffold layer is larger than the pore size of the electrospun fibrous membrane layer. The pore size of the 3D printed scaffold layer is 100-1000 ?m, and the fiber diameter of the electrospun fibrous membrane layer is 300-5000 nm. The electrospun fibrous membrane layer is in a random distribution or an oriented arrangement or has a mesh structure. The thickness of the electrospun fibrous membrane layer is 0.08-1 mm.

Abstract: A functionally gradient material for guided periodontal hard and soft tissue regeneration includes a 3D printed scaffold layer and an electrospun fibrous membrane layer. The content of hydroxyapatite in the 3D printed scaffold layer is higher than the content of hydroxyapatite in the electrospun fibrous membrane layer. The pore size of the 3D printed scaffold layer is larger than the pore size of the electrospun fibrous membrane layer. The pore size of the 3D printed scaffold layer is 100-1000 ?m, and the fiber diameter of the electrospun fibrous membrane layer is 300-5000 nm. The electrospun fibrous membrane layer is in a random distribution or an oriented arrangement or has a mesh structure. The thickness of the electrospun fibrous membrane layer is 0.08-1 mm.

Abstract: The disclosure provides a method for preventing marine biofouling by using the principle of harmonic vibration. The method includes coating a surface of a device to be disposed in water with an elastic material layer. The elastic material may vibrate harmonically under the influence of the water traveling wave, thereby forming a cosine wave form. Taking “a” as the wavelength of the harmonic vibration, “b” as the amplitude of the harmonic vibration and “L” as the body length of a mussel larva, an algae larva or a barnacle larva, where L/2 is larger than “a” or “b”, the larva will be easily stripped off under the effect of harmonic vibration. The frequency of the cosine wave ranges from 0.02 Hz to 0.1 Hz so that the larva has insufficient time to stay, thereby preventing the larva from attaching.