Abstract: The invention relates to a process for continuously producing chlorine dioxide comprising the steps of:

Abstract: The present invention provides an improved process for the purification of crude terephthalic acid which has been produced by the oxidation of para-xylene. The process comprises contacting the crude terephthalic acid with oxygen-containing gas at a temperature of about 190.degree. to 230.degree. C. and a pressure of about 1500 to 3600 kPa in the presence of a solvent comprising an alkanoic acid which is preferably acetic acid. The process further comprises the use of a novel and surprisingly effective catalyst system. The catalyst system comprises cobalt, a bromine source, and pyridine.

Abstract: A system for ascertaining the bearing of a remotely-located acoustic signal ource including a hydrophone array having an omnidirectional hydrophone and a pair of orthogonally-oriented directional hydrophones all of whose output signals are applied to a processor which combines the output signals of the directional hydrophones to provide a signal shifted in phase relative to the omnidirectional output signal by an amount equal to the bearing angle and which resolves the phase-shifted signal by phase detection into a pair of signals representative of the sine and cosine of the bearing angle. The sine and cosine signals are processed by integrators and a bearing angle computer to provide an output signal indicative of the bearing angle to a display. A second embodiment of the processor combines the directional hydrophone output signals into a pair of phase shifted signals for resolution, one leading and the other lagging the phase of the omnidirectional signal by an amount equal to the bearing angle.

Abstract: A modular buoy system in which a number of similar sonobuoys are housed in a common container. Associated with each sonobuoy is a launching mechanism. A circuit is provided for actuating these launching mechanisms separately so that the sonobuoys may be ejected from the container one at a time.

Abstract: A hydrophone array system comprising a plurality of hydrophones fastened to a cable is deployed beneath the sea in a substantially horizontal straight line. A small powered thruster fastened to one end of the cable urges it in a first direction and this urging is resisted by a member, such as a drogue or an anchored subsurface float, fastened to the other end of the cable. Individual signals from each of the hydrophones are conducted to the surface where they are processed and transmitted by a radio link to a nearby aircraft or surface vessel. Beam forming and analysis is performed aboard the aircraft or surface vessel.

Abstract: An underwater direction finding system includes a pair of directional hydrophones and a compass in a novel arrangement which associates the signals from all three elements with a single subcarrier. Subsequent demodulation of the subcarrier signals in an airplane or ship then provides directional information directly referenced to the earth's magnetic coordinates.