Abstract: Provided is a semiconductor device in which a boundary region between a transistor portion and a diode portion includes: a first portion which is in contact with the transistor portion and is not provided with a lifetime adjustment region; and a second portion which is in contact with the diode portion and to which the lifetime adjustment region of the diode portion extends, a density distribution of a lifetime killer in a first direction has a lateral slope where a density of the lifetime killer decreases from the second portion of the boundary region toward the first portion, a width of the first portion is smaller than a width of the second portion in the first direction, and the width of the first portion is equal to or larger than a width of the lateral slope in the first direction.

Abstract: A method for producing hydrogen of the present invention includes thermally reducing a reaction medium in which CeO2 is doped with a metal other than Ce and bringing the thermally reduced reaction medium into contact with water to oxidize the reaction medium and to generate the hydrogen. When a reaction temperature in the thermally reducing the reaction medium is defined as T1 [° C.] and a reaction temperature in the bringing the thermally reduced reaction medium into contact with the water is defined as T2 [° C.], a relation of T1?T2?150 is satisfied. It is preferred that a series of processes including the thermally reducing the reaction medium and the bringing the thermally reduced reaction medium into contact with the water is repeated.

Abstract: A method for producing hydrogen of the present invention includes thermally reducing a reaction medium in which CeO2 is doped with a metal other than Ce and bringing the thermally reduced reaction medium into contact with water to oxidize the reaction medium and to generate the hydrogen. When a reaction temperature in the thermally reducing the reaction medium is defined as T1 [° C.] and a reaction temperature in the bringing the thermally reduced reaction medium into contact with the water is defined as T2 [° C.], a relation of T1?T2?150 is satisfied. It is preferred that a series of processes including the thermally reducing the reaction medium and the bringing the thermally reduced reaction medium into contact with the water is repeated.

Abstract: A heat receiver, a reactor, and a heater utilize the heat of concentrated solar light for thermal decomposition and/or chemical reaction of coals, etc. The heat receiver includes: a side portion forming a substantially cylindrical side surface; a substantially circular bottom portion connected to the lower edge of the side portion; and a ceiling connected to the upper edge of the side portion. A substantially circular aperture is formed in the center of the ceiling. The heat receiver has a substantially cylindrical cavity and the opening portion is open. When the cavity has a diameter of D and a length of L, and the aperture has a diameter of d, d=D/2 or less and L=2D or more. Concentrated solar light entering the heat receiver is to be contained in the heat receiver to effectively utilize the solar light.

Abstract: A heat receiver, a reactor, and a heater utilize the heat of concentrated solar light for thermal decomposition and/or chemical reaction of coals, etc. The heat receiver includes: a side portion forming a substantially cylindrical side surface; a substantially circular bottom portion connected to the lower edge of the side portion; and a ceiling connected to the upper edge of the side portion. A substantially circular aperture is formed in the center of the ceiling. The heat receiver has a substantially cylindrical cavity and the opening portion is open. When the cavity has a diameter of D and a length of L, and the aperture has a diameter of d, d=D/2 or less and L=2D or more. Concentrated solar light entering the heat receiver is to be contained in the heat receiver to effectively utilize the solar light.

Abstract: The disclosed method for producing hydrogen by means of thermochemical water-splitting can efficiently use solar energy obtained by means of a beam-down typed light collecting system. Further disclosed is a device for producing hydrogen. While circulating within a reactor (1) a fluidized bed (2) made of metal oxide particles, two reactions are simultaneously caused to proceed: a thermal reduction reaction, which is an oxygen evolution reaction wherein a portion of the fluidized bed (2) is heated by solar light (S) in a nitrogen atmosphere, which is a low oxygen partial pressure gas, releasing oxygen from the metal oxide; and a thermochemical water-splitting reaction, which is a hydrogen evolution reaction wherein water vapor is brought into contact with the metal oxide after oxygen has been released, generating hydrogen.

Abstract: The disclosed method for producing hydrogen by means of thermochemical water-splitting can efficiently use solar energy obtained by means of a beam-down typed light collecting system. Further disclosed is a device for producing hydrogen. While circulating within a reactor (1) a fluidized bed (2) made of metal oxide particles, two reactions are simultaneously caused to proceed: a thermal reduction reaction, which is an oxygen evolution reaction wherein a portion of the fluidized bed (2) is heated by solar light (S) in a nitrogen atmosphere, which is a low oxygen partial pressure gas, releasing oxygen from the metal oxide; and a thermochemical water-splitting reaction, which is a hydrogen evolution reaction wherein water vapor is brought into contact with the metal oxide after oxygen has been released, generating hydrogen.

Abstract: Disclosed is a reactive working material for use in a process of producing hydrogen by splitting water based on a two-step thermochemical water-splitting cycle through the utilization of solar heat, industrial waste heat or the like, which comprises a ferrite fine powder and a cubic zirconia supporting the ferrite fine powder. This reactive working material makes it possible to prevent scaling off of the ferrite fine powder from the zirconia fine powder due to volumetric changes of the ferrite fine powder during repeated use, and suppress growth of FeO grains due to repetition of melting and solidification when used as a reactive working material for a cyclic reaction under a high temperature of 1400° C. or more.

Abstract: Disclosed is a reactive working material for use in a process of producing hydrogen by splitting water based on a two-step thermochemical water-splitting cycle through the utilization of solar heat, industrial waste heat or the like, which comprises a ferrite fine powder and a cubic zirconia supporting the ferrite fine powder. This reactive working material makes it possible to prevent scaling off of the ferrite fine powder from the zirconia fine powder due to volumetric changes of the ferrite fine powder during repeated use, and suppress growth of FeO grains due to repetition of melting and solidification when used as a reactive working material for a cyclic reaction under a high temperature of 1400° C. or more.

Abstract: Disclosed is a reactive working material for use in a process of producing hydrogen by splitting water based on a two-step thermochemical water-splitting cycle through the utilization of solar heat, industrial waste heat or the like, which comprises a ferrite fine powder and a cubic zirconia supporting the ferrite fine powder. This reactive working material makes it possible to prevent scaling off of the ferrite fine powder from the zirconia fine powder due to volumetric changes of the ferrite fine powder during repeated use, and suppress growth of FeO grains due to repetition of melting and solidification when used as a reactive working material for a cyclic reaction under a high temperature of 1400° C. or more.