Abstract: The present invention is a method for producing a silver halide emulsion. The precipitation of the emulsion is carried out away from the rotary agitator. The reactant solutions are introduced into the reactor very close to the tip of one or more ultrasonic horns that are placed away from the agitator. The ultrasonic horns are efficient sources for controlling micromixing, while the agitator controls the macromixing in the reactor.

Abstract: An apparatus and method for determining the position of an object, especially the position of a movable object in an industrial vessel. The position is determined by the use of two signals having a very large difference in their velocities, such as electromagnetic and acoustic waves. The object whose position is to be determined receives the electromagnetic signal, analyzes the electromagnetic signal, and, if appropriate, transmits an acoustic signal. In addition to the object containing an electromagnetic receiver and an acoustic transmitter, there is required an electromagnetic transmitter, three or more receivers to receive the acoustic signal from the object, and supporting equipment to process signals and log data. When the object transmits an acoustic signal, the acoustic receivers, which are in known positions in the vessel, receive the signal at different times depending on the distance of the object from each receiver.