Abstract: Provided is a method of producing various 2-((meth)allyloxymethyl)acrylic acid derivatives in high yields with no need to load a raw material in a large excess for improving a reaction conversion ratio, and without use of a catalyst having high toxicity or a strong acid catalyst. Also provided are powder compounds that may be utilized as raw materials for synthesizing various chemical products. A method of producing a 2-((meth)allyloxymethyl)acrylic acid derivative includes causing the powder of a salt of a 2-((meth)allyloxymethyl)acrylic acid anion and an alkali metal cation (component A), and a halide (component B) to react with each other to produce a 2-((meth)allyloxymethyl)acrylic acid derivative. The 2-((meth)allyloxymethyl)acrylic acid alkali metal salt powder is the powder of a salt of a 2-((meth)allyloxymethyl)acrylic acid anion and an alkali metal cation, and has a bulk density of 0.50 g/mL or more, or a water content of 0.05 wt % or less.

Abstract: A method for producing an optical wavelength conversion member (9) composed of a sintered body containing, as main components, Al2O3 and a component represented by formula A3B5O12:Ce; an optical wavelength conversion member; an optical wavelength conversion component including the optical wavelength conversion member; and a light-emitting device including the optical wavelength conversion member or the optical wavelength conversion component. The production method of the sintered body includes firing in a firing atmosphere having a pressure of 104 Pa or more and an oxygen concentration of 0.8 vol. % or more and less than 25 vol. %.

Abstract: Provided is a method of producing various 2-((meth)allyloxymethyl)acrylic acid derivatives in high yields with no need to load a raw material in a large excess for improving a reaction conversion ratio, and without use of a catalyst having high toxicity or a strong acid catalyst. Also provided are powder compounds that may be utilized as raw materials for synthesizing various chemical products. A method of producing a 2-((meth)allyloxymethyl)acrylic acid derivative includes causing the powder of a salt of a 2-((meth)allyloxymethyl)acrylic acid anion and an alkali metal cation (component A), and a halide (component B) to react with each other to produce a 2-((meth)allyloxymethyl)acrylic acid derivative. The 2-((meth)allyloxymethyl)acrylic acid alkali metal salt powder is the powder of a salt of a 2-((meth)allyloxymethyl)acrylic acid anion and an alkali metal cation, and has a bulk density of 0.50 g/mL or more, or a water content of 0.05 wt % or less.

Abstract: An optical wavelength conversion member and a light-emitting device including the optical wavelength conversion member. The light-emitting device (1) includes a container (3), a light-emitting element (5), and an optical wavelength conversion member (9). The optical wavelength conversion member (9) is composed of a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains of a component represented by formula A3B5O12:Ce. Specifically, A and B of the A3B5O12 individually represent at least one element selected from the following element groups: A: Sc, Y, and lanthanoids (except for Ce), and B: Al and Ga; the at least one element selected from the element groups is present in each crystal grain and the crystal grain boundary of the ceramic sintered body; and the element concentration of the crystal grain boundary is higher than the element concentration of the crystal grain.

Abstract: The durability of a ceramic sintered body is improved, and a reduction in its light emission intensity and the occurrence of a chromaticity variation are suppressed. The ceramic sintered body contains alumina and a compound represented by M13-XM2XM35O12. The volume percent of the compound in the ceramic sintered body is from 3% to 70% inclusive. The ratio of the intensity of XRD from a complex oxide of aluminum and M2 to the intensity of XRD from the compound in the ceramic sintered body is less than 0.05. The average grain diameter of the alumina contained in the ceramic sintered body is from 0.30 (?m) to 3.00 (?m) inclusive. M1 is at least one selected from Sc, Y, and lanthanoid elements, and M2 is at least one selected from lanthanoid elements except any lanthanoid element selected for M1. M3 is at least one of Al and Ga, and X is from 0.003 to 0.500 inclusive.

Abstract: An optical wavelength conversion member and a light-emitting device including the optical wavelength conversion member. The optical wavelength conversion member (9) is formed of a ceramic sintered body having a fluorescent phase containing fluorescent crystal grains as a main component and a translucent phase containing translucent crystal grains as a main component. Crystal grains of the fluorescent phase have a composition represented by formula A3B5O12:Ce, where the element A is selected from Sc, Y, and lanthanoids (except for Ce), and the element B is selected from Al and Ga. In the optical wavelength conversion member (9), 0.3<a<34 and 300 ?m<y<1,050 ?m are satisfied, wherein a represents the area ratio of the translucent phase to the fluorescent phase in a cross section of the optical wavelength conversion member (9), and y represents the interfacial length of the fluorescent phase.

Abstract: An optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains of a component represented by formula A3B5O12:Ce, wherein A is at least one element selected from Sc, Y and lanthanoids (except for Ce), and B is at least one element selected from Al and Ga. Further, the following relations are satisfied: 0%?X?25%, 9%?Y?45%, and 48%?Z?90%, wherein X represents a proportion corresponding to the ratio a/N, Y represents a proportion corresponding to the ratio b/N, and Z represents a proportion corresponding to the ratio c/N and a, b, c and N are as defined herein. Also disclosed is a light-emitting device including the optical wavelength conversion member.

Abstract: An optical wavelength conversion member and a light-emitting device including the optical wavelength conversion member. The optical wavelength conversion member (9) is formed of a ceramic sintered body having a fluorescent phase containing fluorescent crystal grains as a main component and a translucent phase containing translucent crystal grains as a main component. Crystal grains of the fluorescent phase have a composition represented by formula A3B5O12:Ce, where the element A is selected from Sc, Y, and lanthanoids (except for Ce), and the element B is selected from Al and Ga. In the optical wavelength conversion member (9), 0.3<a<34 and 300 ?m<y<1,050 ?m are satisfied, wherein a represents the area ratio of the translucent phase to the fluorescent phase in a cross section of the optical wavelength conversion member (9), and y represents the interfacial length of the fluorescent phase.

Abstract: A method for producing an optical wavelength conversion member (9) composed of a sintered body containing, as main components, Al2O3 and a component represented by formula A3B5O12:Ce; an optical wavelength conversion member; an optical wavelength conversion component including the optical wavelength conversion member; and a light-emitting device including the optical wavelength conversion member or the optical wavelength conversion component. The production method of the sintered body includes firing in a firing atmosphere having a pressure of 104 Pa or more and an oxygen concentration of 0.8 vol. % or more and less than 25 vol. %.

Abstract: An optical wavelength conversion member and a light-emitting device including the optical wavelength conversion member. The light-emitting device (1) includes a container (3), a light-emitting element (5), and an optical wavelength conversion member (9). The optical wavelength conversion member (9) is composed of a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains of a component represented by formula A3B5O12:Ce. Specifically, A and B of the A3B5O12 individually represent at least one element selected from the following element groups: A: Sc, Y, and lanthanoids (except for Ce), and B: Al and Ga; the at least one element selected from the element groups is present in each crystal grain and the crystal grain boundary of the ceramic sintered body; and the element concentration of the crystal grain boundary is higher than the element concentration of the crystal grain.

Abstract: The durability of a ceramic sintered body is improved, and a reduction in its light emission intensity and the occurrence of a chromaticity variation are suppressed. The ceramic sintered body contains alumina and a compound represented by M13-XM2XM35O12. The volume percent of the compound in the ceramic sintered body is from 3% to 70% inclusive. The ratio of the intensity of XRD from a complex oxide of aluminum and M2 to the intensity of XRD from the compound in the ceramic sintered body is less than 0.05. The average grain diameter of the alumina contained in the ceramic sintered body is from 0.30 (?m) to 3.00 (?m) inclusive. M1 is at least one selected from Sc, Y, and lanthanoid elements, and M2 is at least one selected from lanthanoid elements except any lanthanoid element selected for M1. M3 is at least one of Al and Ga, and X is from 0.003 to 0.500 inclusive.

Abstract: An optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains of a component represented by formula A3B5O12:Ce, wherein A is at least one element selected from Sc, Y and lanthanoids (except for Ce), and B is at least one element selected from Al and Ga. Further, the following relations are satisfied: 0%?X?25%, 9%?Y?45%, and 48%?Z?90%, wherein X represents a proportion corresponding to the ratio a/N, Y represents a proportion corresponding to the ratio b/N, and Z represents a proportion corresponding to the ratio c/N and a, b, c and N are as defined herein. Also disclosed is a light-emitting device including the optical wavelength conversion member.

Abstract: A photon counting type X-ray computed tomography apparatus includes an X-ray tube, a detector, a raw data generating section, an information compression section, and a data transmission section. The X-ray tube is configured to irradiate an X-ray. The detector is configured to count photons derived from the irradiated X-ray. The raw data generating section is configured to collect results of counting performed by the detector and to generate, from the results of counting, raw data for each of a plurality of energy bands. The information compression section is configured to compare values of the raw data between the raw data generated respectively for the energy bands, and to perform information compression of each of the raw data. The data transmission section is configured to transmit the raw data compressed by the information compression.

Abstract: In a ceramic composition mainly composed of alumina (Al2O3), tungsten carbide (WC) and zirconia (ZrO2), zirconium (Zr) is distributed in a first grain boundary as an interface where an alumina (Al2O3) crystal grain is adjacent to a tungsten carbide (WC) crystal grain and in a second grain boundary as an interface where two alumina (Al2O3) crystal grains are adjacent to each other.

Abstract: In a ceramic composition mainly composed of alumina (Al2O3), tungsten carbide (WC) and zirconia (ZrO2), zirconium (Zr) is distributed in a first grain boundary as an interface where an alumina (Al2O3) crystal grain is adjacent to a tungsten carbide (WC) crystal grain and in a second grain boundary as an interface where two alumina (Al2O3) crystal grains are adjacent to each other.

Abstract: A positron emission computed tomography apparatus according to an embodiment includes a detector, a buffer, and a regulating unit. The detector detects annihilation radiation. The buffer stores therein event data generated based on an output signal from the detector. The regulating unit regulates the amount of the event data read from the buffer during a high count rate period of the events at which the annihilation radiation is detected.

Abstract: A ceramic sintered body includes tungsten carbide, zirconia, and alumina. The content of the tungsten carbide is 20 to 50 vol %, and the content of the zirconia is 5 to 25 vol %. The crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals. The ceramic sintered body does not substantially include Ti compounds. The average particle diameter of the tungsten carbide, the average particle diameter of the zirconia, and the average particle diameter of the alumina are all 1 ?m or less.

Abstract: A sintered body containing alumina crystal particles and zirconia crystal particles as main components includes the tetragonal crystal particles as the zirconia crystal particles. The zirconia crystal particles satisfy relations 0%?A?3%, 3%?B?22% and 77%?C?96%,where A, B and C are as defined herein.

Abstract: A ceramic sintered body includes tungsten carbide, zirconia, and alumina. The content of the tungsten carbide is 20 to 50 vol %, and the content of the zirconia is 5 to 25 vol %. The crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals. The ceramic sintered body does not substantially include Ti compounds. The average particle diameter of the tungsten carbide, the average particle diameter of the zirconia, and the average particle diameter of the alumina are all 1 ?m or less.

Abstract: A photon counting type X-ray computed tomography apparatus includes an X-ray tube, a detector, a raw data generating section, an information compression section, and a data transmission section. The X-ray tube is configured to irradiate an X-ray. The detector is configured to count photons derived from the irradiated X-ray. The raw data generating section is configured to collect results of counting performed by the detector and to generate, from the results of counting, raw data for each of a plurality of energy bands. The information compression section is configured to compare values of the raw data between the raw data generated respectively for the energy bands, and to perform information compression of each of the raw data. The data transmission section is configured to transmit the raw data compressed by the information compression.