摘要:
A passive cooling and depressurization system for a pressurized water nuclear plant is provided with a cooling water pool, a steam supply piping, a heat exchanger, a steam supply valve, a coolant return pipe and an outlet valve. The steam supply piping extends from the gas phase of the pressurizer. The heat exchanger exchanges heat between water stored in the cooling water pool and steam flowing through the steam supply piping. The steam supply valve is equipped on the steam supply piping. The coolant return pipe extends from the heat exchanger to a liquid phase of the reactor pressure boundary. The outlet valve is equipped on the coolant return pipe.
摘要:
A passive cooling and depressurization system for a pressurized water nuclear plant is provided with a cooling water pool, a steam supply piping, a heat exchanger, a steam supply valve, a coolant return pipe and an outlet valve. The steam supply piping extends from the gas phase of the pressurizer. The heat exchanger exchanges heat between water stored in the cooling water pool and steam flowing through the steam supply piping. The steam supply valve is equipped on the steam supply piping. The coolant return pipe extends from the heat exchanger to a liquid phase of the reactor pressure boundary. The outlet valve is equipped on the coolant return pipe.
摘要:
A containment vessel for containing a reactor pressure vessel, a reactor core, and a steam generator of a pressurized water reactor includes a main body equipped with a polar crane, a diaphragm set above the polar crane that partitions the main body, before and after a loss-of-coolant accident (LOCA), into an upper vessel including a dome part having an open space and a lower vessel isolated from the upper vessel, a pressure suppression chamber including a suppression pool that stores water and a gas phase in communication with the open space, a LOCA vent pipe connecting the suppression pool to the lower vessel, and a vacuum breaker that equalizes pressure by allowing gas flow from the upper to the lower vessel when a pressure difference between the upper and lower vessels exceeds a preset value. The lower vessel contains all equipment and piping constituting a reactor pressure boundary.
摘要:
According to an embodiment, a pressurized water reactor plant has a primary system which includes: a reactor vessel for housing a reactor core which is cooled by a primary coolant, a single steam generator, a hot leg pipe for connecting the reactor vessel and the steam generator, cold leg pipes, at least two primary coolant pumps, and a pressurizer for pressurizing the primary coolant pressure boundary in which the primary coolant flows. The plant also has: a passive cooling and depressurization system which is a primary depressurization means for equalizing the primary system pressure to the secondary system pressure at the time of a tube rupture accident of the steam generator, and a reactor containment vessel containing the primary system and cooling the primary system by air cooling. Thus, a compact pressurized water rector with high economic efficiency, safety, and reliability can be provided.
摘要:
Illumination devices (7a) and (7b) which irradiate light having a wavelength of 1.1 μm or less are arranged on a front surface and a rear surface of a cover (8) of a dicing device (1). After a wafer is placed on a dicing stage (3), when the wafer is diced by a blade (4a) attached to a spindle (5), light is irradiated on an entire surface of an upper surface (element forming surface) of the wafer by the illumination devices (7a) and (7b). At this time, an illuminance of light on the wafer is set at 70 lux or more and 2000 lux or less. By this means, during a dicing operation, an area to be a light-shielded area by the spindle (5) or the like is not present on the wafer.
摘要:
Illumination devices (7a) and (7b) which irradiate light having a wavelength of 1.1 μm or less are arranged on a front surface and a rear surface of a cover (8) of a dicing device (1). After a wafer is placed on a dicing stage (3), when the wafer is diced by a blade (4a) attached to a spindle (5), light is irradiated on an entire surface of an upper surface (element forming surface) of the wafer by the illumination devices (7a) and (7b). At this time, an illuminance of light on the wafer is set at 70 lux or more and 2000 lux or less. By this means, during a dicing operation, an area to be a light-shielded area by the spindle (5) or the like is not present on the wafer.
摘要:
Illumination devices (7a) and (7b) which irradiate light having a wavelength of 1.1 μm or less are arranged on a front surface and a rear surface of a cover (8) of a dicing device (1). After a wafer is placed on a dicing stage (3), when the wafer is diced by a blade (4a) attached to a spindle (5), light is irradiated on an entire surface of an upper surface (element forming surface) of the wafer by the illumination devices (7a) and (7b). At this time, an illuminance of light on the wafer is set at 70 lux or more and 2000 lux or less. By this means, during a dicing operation, an area to be a light-shielded area by the spindle (5) or the like is not present on the wafer.
摘要:
A method for producing a fuel cell electrode catalyst, including a step (I) of bringing an aqueous solution of a transition metal compound (1) into contact with ammonia and/or ammonia water to generate a precipitate (A) containing an atom of the transition metal, a step (II) of mixing at least the precipitate (A), an organic compound (B), and a liquid medium (C) to obtain a catalyst precursor liquid, and a step (IV) of subjecting the solid in the catalyst precursor liquid to heat treatment at a temperature of 500 to 1200° C. to obtain an electrode catalyst; a portion or the entirety of the transition metal compound (1) being a compound containing a transition metal element of group 4 or group 5 of the periodic table; and the organic compound (B) being at least one selected from sugars and the like.
摘要:
A containment vessel has an inner shell covering a reactor pressure vessel and an outer shell forming an outer well which is a gas-tight space covering the horizontal outer periphery of the inner shell. The inner shell has a first cylindrical side wall surrounding the horizontal periphery of the reactor pressure vessel, a containment vessel head which covers the upper part of the reactor pressure vessel, and a first top slab connecting in a gas-tight manner the periphery of the containment vessel head and the upper end of the first cylindrical side wall. The outer shell has a second cylindrical side wall surrounding the outer periphery of the first cylindrical side wall, and also has a second to slab connecting in a gas-tight manner the vicinity of the upper end of the second cylindrical side wall and the first cylindrical side wall.
摘要:
A power supply device supplying power to a device via a power line is provided, where the power supply device includes a first voltage generation unit configured to generate and supply a first direct voltage to the power line, a second voltage generation unit configured to generate and supply a second direct voltage lower than the first direct voltage to the power line, a measurement unit configured to measure a voltage of the power line, a control unit configured to control supply of the first direct voltage with the first voltage generation unit after starting supply of the second direct voltage with the second voltage generation unit, and a determination unit configured to determine a state of the power supply device based on the measured voltage and a first threshold value after starting the supply of the second direct voltage.