Abstract: A developer includes a toner containing toner particles and a carrier containing carrier particles. The toner particles each include a toner mother particle and external additive particles attached to a surface of the toner mother particle. The external additive particles include first silica particles and spacer particles. The first silica particles have a number average primary particle diameter of at least 10 nm and no greater than 30 nm. The spacer particles have a number average primary particle diameter of at least 32 nm and no greater than 145 nm. The spacer particles in the toner particles have a coverage ratio of at least 2.0% by area and no greater than 40.0% by area. The carrier particles each include a carrier mother particle and strontium titanate particles attached to a surface of the carrier mother particle.

Abstract: Toner particles in a developer include first strontium titanate particles attached to the surface of each toner mother particle thereof. The first strontium titanate particles have a content ratio of 0.3 to 0.9 parts by mass to 100.0 parts by mass of the toner mother particles. In the developer, coat layers of carrier mother particles of first carrier particles contain barium titanate particles and a coating resin including silicone resin. The barium titanate particles have a content ratio of 2 to 47 parts by mass to 100 parts by mass of the coating resin. Second strontium titanate particles attached to the surfaces of the carrier mother particles have a diameter of 15 to 85 nm.

Abstract: Configuring the inside of a tooth portion 15 of a toothed belt 10 with a core rubber layer 14 and the outer periphery of the tooth portion 15 with a tooth rubber layer 12. Also, including short fibers in the core rubber layer 14. The tooth rubber layer 12 is formed by curing a rubber composition containing 10 parts by weight or less high-density polyethylene with 100 parts by weight of matrix rubber. The value of tan ? for the tooth rubber layer 12 at 100-120° C. is maintained at 0.100-0.120.

Abstract: Configuring the inside of a tooth portion 15 of a toothed belt 10 with a core rubber layer 14 and the outer periphery of the tooth portion 15 with a tooth rubber layer 12. Also, including short fibers in the core rubber layer 14. The tooth rubber layer 12 is formed by curing a rubber composition containing 10 parts by weight or less high-density polyethylene with 100 parts by weight of matrix rubber. The value of tan ? for the tooth rubber layer 12 at 100-120° C. is maintained at 0.100-0.120.

Abstract: A first motor-actuated expansion valve and a second motor-actuated expansion valve which are connected in parallel with each other in back-to-back connection are provided between an outdoor heat exchanger and an indoor heat exchanger. In the first motor-actuated expansion valve, at the time of non-operation and full closure, when the refrigerant pressure on the indoor heat exchanger side is higher than the refrigerant pressure on the outdoor heat exchanger side by a predetermined value or more, the full closure is released by receiving the refrigerant pressure on the indoor heat exchanger side. In the second motor-actuated expansion valve, at the time of non-operation and full closure, when the refrigerant pressure on the outdoor heat exchanger side is higher than the refrigerant pressure on the indoor heat exchanger side by a predetermined value or more, the full closure is released by receiving the refrigerant pressure on the outdoor heat exchanger side.

Abstract: A first motor-actuated expansion valve and a second motor-actuated expansion valve which are connected in parallel with each other in back-to-back connection are provided between an outdoor heat exchanger and an indoor heat exchanger. In the first motor-actuated expansion valve, at the time of non-operation and full closure, when the refrigerant pressure on the indoor heat exchanger side is higher than the refrigerant pressure on the outdoor heat exchanger side by a predetermined value or more, the full closure is released by receiving the refrigerant pressure on the indoor heat exchanger side. In the second motor-actuated expansion valve, at the time of non-operation and full closure, when the refrigerant pressure on the outdoor heat exchanger side is higher than the refrigerant pressure on the indoor heat exchanger side by a predetermined value or more, the full closure is released by receiving the refrigerant pressure on the outdoor heat exchanger side.

Abstract: A filter element comprises an oil-impregnated filtering member, and a transmission preventing layer formed on a downstream side of the filtering member, for restricting transmission of at least the carbon dusts from the oil-impregnated filtering member. The filtering member may be formed like a ridge-like-folded structure. The transmission preventing layer may be formed of a coating layer having a resistance against a viscous oil that is impregnated in the filtering member. This coating layer may be formed uniformly as a whole or the thickness or the content of the coating layer may be increased partially. A ventilation shutting-off member (filling layer) may be formed as the transmission preventing layer in the root portion areas of the ridge portions. The transmission preventing layer may comprise a resistant component that is insoluble in the oil that is impregnated in the filtering member.

Abstract: A filter element comprises an oil-impregnated filtering member, and a transmission preventing layer formed on a downstream side of the filtering member, for restricting transmission of at least the carbon dusts from the oil-impregnated filtering member. The filtering member may be formed like a ridge-like-folded structure. The transmission preventing layer may be formed of a coating layer having a resistance against a viscous oil that is impregnated in the filtering member. This coating layer may be formed uniformly as a whole or the thickness or the content of the coating layer may be increased partially. A ventilation shutting-off member (filling layer) may be formed as the transmission preventing layer in the root portion areas of the ridge portions. The transmission preventing layer may comprise a resistant component that is insoluble in the oil that is impregnated in the filtering member.

Abstract: When the trigonometric function of the phase lag of the hydraulic excitation of the runner vanes, which varies in accordance with the combination of the number of runner vanes and the number of guide vanes of a high head pump/turbine, is denoted by cos(.theta..sub.R n), the thickness of the crown along a circle of a diameter at a mid point of the diameter of the outermost periphery of the runner is denoted by t.sub.MC, the thickness of the band is denoted by t.sub.MB, the mean thickness of the crown at the outer peripheral portion of the runner is denoted by t.sub.C, the mean thickness of the band is denoted by t.sub.B, and the rigidity ratio of the crown and band to the runner vane is denoted by K.sub.R taking the rigidity of the runner vane as a reference, the moment coefficient C.sub.MO which is a function of cos(.theta..sub.R N) and the rigidity ratio K.sub.R is selected to be less than 0.5 in accordance with the value of cos(.theta..sub.R n), and relations t.sub.C /t.sub.MC .ltoreq.1 and t.sub. B /t.sub.