Abstract: An ultrasonic surgical device is disclosed including a surgical tool including a proximal transducer mounting portion defining a surface, a distal end effector end, and a waveguide disposed therebetween, the waveguide extending along a longitudinal axis. The ultrasonic surgical device further includes a transducer is in mechanical communication with the surface of the transducer mounting portion. The transducer is configured to operate in a D31 mode with respect to the longitudinal axis of the waveguide. Upon activation by an electrical signal having a predetermined frequency component, the transducer is configured to induce a standing wave in the surgical tool to cause the end effector to vibrate, the standing wave having a wavelength proportional to the predetermined frequency component of the electrical signal.

Abstract: The improved engine exhaust gas muffler of the invention comprises an outer hollow tubular elongated shell having a gas inlet and a gas outlet at opposite ends thereof, and a hollow perforated tubular extension secured to the inlet end of the shell and extending part way along the length of the shell substantially coaxially therewith. A hollow perforated insert substantially coaxial with the shell and having an upstream end slip fitted within the downstream end of the extension and a downstream end either connected to the shell gas outlet or fitted within a lower extension is also provided. The insert's upstream end has a terminal portion of smaller diameter than the main body of the insert so as to form with the extension downstream end means for diverting exhaust gases flowing through the muffler into a plurality of paths for better sound attenuation, and also a pocket for the accumulation of solid particles from exhaust gases without plugging of said paths.