Abstract: A gas circuit breaker includes a sealed tank that includes first and second conductor containers with an insulating tube therebetween and is filled with insulating gas; a fixed arcing contact on the first conductor container side; a movable arcing contact that is provided on the second conductor container side and moves to be able to contact and separate from the fixed arcing contact; a fixed conductive contact on the first conductor container side; a movable conductive contact that moves in accordance with contact and separation of the movable arcing contact and contacts and separates from the fixed conductive contact; and a puffer unit that is provided on the second conductor container side and has a mechanical puffer chamber accommodating the movable conductive contact formed therein, wherein the puffer unit is arranged between the insulating tube and the second conductor container and is exposed to the periphery of the sealed tank.

Abstract: In accordance with the present invention, there is provided a calcium removal method capable of reducing operation cost. A solution L2 containing potassium or/and sodium, and calcium is passed through an ion-exchange resin 35 to separate the solution into a solution containing potassium or/and the sodium, and a solution containing calcium. Operation cost can remarkably be decreased since potassium carbonate is not required to remove calcium as before. Timing for changing a calcium-containing water L3 and a salt water L4 discharged from the ion-exchange resin can be performed based on at least one measurement result selected from the group consisting of: a calcium or chlorine concentration; electrical conductivity; and pH of a fluid which is discharged from said ion-exchange resin. The solution may be a filtrate L1 that is obtained by washing a chlorine bypass dust D generated in a cement burning process, or a leachate W of a final disposal site 50.

Abstract: A soldering method in which, out of soldering steps of (a) during soldering, (b) before soldering, and (c) after soldering, in at least the steps of (a) during soldering and (b) before soldering, an alternating current whose frequency temporally changes in a band of 20 Hz-1 MHz is applied to at least any of (d) a solder material, (e) a soldering object, and (f) a peripheral portion thereof, and a modulated electromagnetic wave treatment is carried out by use of an electromagnetic field induced by the alternating current. Thereby, when not only a lead-containing solder material but also a lead-free solder material are used, wettability in soldering to a soldering object is made better, and an obtained soldered article is improved in strength, etc., compared to the conventional solder material.