Abstract: A behind-the-ear hearing aid includes a case having an accommodating chamber, an apparatus for processing sounds, an ear hook, and a battery assembly. The apparatus is mounted in the case. The battery assembly is detachably mounted in the accommodating chamber and electrically connected to the apparatus. When the power of the battery assembly is used up, the hearing aid can be continuously used by disassembling and replacing a new battery assembly, thereby solving the problem that the battery assembly in the existing hearing aid cannot be dissembled and replaced. It is environmentally friendly and convenient for use.

Abstract: Disclosed is a microfluidic system based on an artificially structured acoustic field, comprising a microcavity used to accommodate a solution containing particles and a ultrasonic emission device used to emit ultrasound, and further comprising a phononic crystal plate placed in the microcavity. The phononic crystal plate has an artificial cycle structure, and is used to modulate the acoustic field so as to control the particles. Also disclosed is a method of controlling microfluid particles based on an artificially structured acoustic field. In the particular embodiments, since a microcavity, an ultrasonic emission device and a phononic crystal plate are comprised, the ultrasonic emission device is used to emit ultrasound, and the phononic crystal plate has an artificial cycle structure, and is used to modulate the acoustic field so as to control the particles.

Abstract: Disclosed is a microfluidic system based on an artificially structured acoustic field, comprising a microcavity and a ultrasonic emission device, wherein the microcavity is used to accommodate a solution containing particles, the ultrasonic emission device is used to emit ultrasound, and characterized in further comprising a phononic crystal plate placed in the microcavity, wherein the phononic crystal plate has an artificial cycle structure, and is used to modulate the acoustic field so as to control the particles. Also disclosed is a method of controlling microfluid particles based on an artificially structured acoustic field. In the particular embodiments, since a microcavity, an ultrasonic emission device and a phononic crystal plate are comprised, the ultrasonic emission device is used to emit ultrasound, and the phononic crystal plate has an artificial cycle structure, and is used to modulate the acoustic field so as to control the particles.