Abstract: An exhaust heat exchanger system recovers heat from exhaust gas emitted from a prime mover, for example, a diesel engine, gas engine, gas turbine, etc., and/or to reduce harmful components such as NO.sub.X (nitrogen oxides). A high-temperature side heat exchanger section and a low-temperature side heat exchanger section are disposed in a single casing and these heat exchanger sections are connected together through a duct. An exhaust gas purifying catalyst is disposed in the duct. Accordingly, it is possible to simplify the mechanism of the exhaust heat exchanger system, reduce the overall size of the system, lower the production cost and minimize the installation space. Further, the exhaust gas purifying operation is efficiently carried out by the action of the catalyst.

Abstract: The present invention is directed to a method for forming a thin film on a substrate by the use of a glow discharge plasma which comprises generating a magnetic field in a direction which crosses an electric field for discharge at right angles and fluctuating the magnetic field.

Abstract: An automated ultrasonic examination system for heat transfer tubes in a boiler makes it possible to perform ultrsonic examination from inside of the heat transfer tubes without necessitating the removal of scale from the outer surfaces of the boiler tubes by polishing and without necessitating access to places where manual measurements are difficult or impossible to make.

Abstract: A steel tube working apparatus is composed of a clamping device consisting of a pair of clamps, a pair of projecting plates, means for actuating the clamps and the projecting plates, a pair of guide bars and a main body frame; a base plate having a pair of guide rollers fitting to the guide bars fixedly secured to its opposite ends; and working means connected to the base plate in a movable and rotatable manner. A cutting device, a beveling device, a welding device, etc. are selectively connected to the base plate as the working means.