Abstract: A gas analyzer apparatus including a support tube having a distal portion arranged in a flue and a gas sensor supported on the support tube. An air supply tube supplies cooling air into the support tube. A basal portion of the gas sensor is cooled by the cooling air.

Abstract: An apparatus includes a boiler for receiving water from a water feed pipe and heating the water into steam and a condenser for condensing the steam into condensate. The condensate is fed back to the boiler through the water feed pipe. A solute source includes a solute which has at least one of oxygen, hydrogen peroxide and ozone. Generating member generates an aqueous solution by dissolving the solute supplied from the solute source into water. Supplying member supplies the aqueous solution to the water feed pipe to form a protective film made of iron oxide on an inner surface of the water feed pipe.

Abstract: This invention relates to a voltage sensor for sensing a voltage on an electrically charged object such as a distribution line or the like, the sensor being disposed with an insulation space to the object. The voltage sensor includes an amplifier circuit for outputting a signal having a waveform similar to that of a displacement current inflowing from the electrically charged object via the insulation space, and a filter circuit for extracting a signal having predetermined frequencies from the output of the amplifier circuit and outputting an alternating current waveform similar to the potential of the electrically charged object.

Abstract: This invention relates to a voltage sensor for sensing a voltage on an electrically charged object such as a distribution line or the like, the sensor being disposed with an insulation space to the object. The voltage sensor includes an amplifier circuit for outputting a signal having a waveform similar to that of a displacement current inflowing from the electrically charged object via the insulation space, and a filter circuit for extracting a signal having predetermined frequencies from the output of the amplifier circuit and outputting an alternating current waveform similar to the potential of the electrically charged object.