Abstract: In a photocatalyst which is obtained by adding a co-catalyst to semiconductor particles containing strontium titanate and which causes a water decomposition reaction in which water molecules are decomposed into oxygen molecules and hydrogen molecules according to light emission, the semiconductor particles are doped with barium or additionally with scandium. A method of synthesizing a semiconductor for the photocatalyst includes a process of synthesizing semiconductor particles containing strontium titanate doped with barium by mixing barium titanate or additionally with scandium oxide into strontium chloride or mixing strontium titanate or additionally scandium oxide into strontium chloride and barium chloride and performing firing.

Abstract: In an apparatus producing hydrogen gas by the decomposition reaction of water using photocatalyst, its miniaturization is achieved while suppressing the decrease of production efficiency of hydrogen gas as low as possible or improving the efficiency. The apparatus 1 comprises a container portion 2 receiving water W; a photocatalyst member 3 immersed in the water, having photocatalyst which generates excited electrons and positive holes when irradiated with light, causes a decomposition reaction of the water and generates hydrogen gas; a light source 4 emitting the light irradiated to the photocatalyst member; and a heat exchange device 7 conducting waste heat of the light source to the water in the container portion; wherein the water to be decomposed on the photocatalyst member in the container portion is warmed by the waste heat of the light source by the heat exchange device.

Abstract: A coating layer for a substrate includes a coating material. The coating material includes graphene and/or graphene derivatives that reflect and/or absorb an electromagnetic (EM) wave having a frequency of above 20 GHz. The coating layer is deposited on a surface of the substrate.

Abstract: A reception unit receives an execution history file of a target program and a software structure file of the target program. An association unit associates each piece of execution element information of the execution history file and each piece of component information of the software structure file with each other, thereby generating an association file. A determination unit determines each execution element and a parent element of each execution element as important elements by referring to the software structure file based on the association file, thereby generating an important element file indicating each important element. A visualization unit generates a visualization diagram indicating the structure of the target program in a state where each important element has been emphasized, based on the important element file and the software structure file.