Abstract: Provided is a separation and recovery apparatus for continuously separating and recovering, from a resin mixture containing a resin containing a hydrolyzable polymer and a resin containing a nonhydrolyzable polymer, a hydrolytic component a of the hydrolyzable polymer A and the nonhydrolyzable polymer B, the apparatus including: a crushing unit that crushes the resin mixture a melting/discharging unit that melts a crushed product obtained by the crushing unit to form a fluid and discharges the fluid at a high pressure; and a hydrothermal reaction treatment unit that continuously subjects the fluid discharged from the melting/discharging unit to a hydrothermal reaction treatment, wherein, in the melting/discharging unit, the hydrolyzable polymer A is hydrolyzed, and the hydrolytic component a thereof is dissolved and transferred into water permeating a sintered alloy diaphragm, thereby separating the nonhydrolyzable polymer B.

Abstract: An ultrasonic sensor includes a signal generation circuit, an amplifier, and a matching circuit as a transmission-side circuit. The signal generation circuit includes a driving signal generation circuit that generates a driving signal for transmitting ultrasonic waves from an ultrasonic transducer for transmission and reception and a reverberation suppression signal generation circuit that generates a reverberation suppression signal for suppressing reverberation occurring at the ultrasonic transducer from which the ultrasonic waves are transmitted. The reverberation suppression signal generation circuit generates the reverberation suppression signal having a frequency of 1/2 times the frequency of the driving signal and applies the reverberation suppression signal to the ultrasonic transducer at a time delayed from the driving signal by a half wavelength.

Abstract: An ultrasonic sensor includes a signal generation circuit, an amplifier, and a matching circuit as a transmission-side circuit. The signal generation circuit includes a driving signal generation circuit that generates a driving signal for transmitting ultrasonic waves from an ultrasonic transducer for transmission and reception and a reverberation suppression signal generation circuit that generates a reverberation suppression signal for suppressing reverberation occurring at the ultrasonic transducer from which the ultrasonic waves are transmitted. The reverberation suppression signal generation circuit generates the reverberation suppression signal having a frequency of 1/2 times the frequency of the driving signal and applies the reverberation suppression signal to the ultrasonic transducer at a time delayed from the driving signal by a half wavelength.