Abstract: According to one embodiment, an active material is provided. The active material includes a Mo-containing niobium-titanium oxide having a monoclinic structure. A ratio I25/I24 of an intensity I25 of a second peak appearing within a range of 2? from 25.0° to 25.5° relative to an intensity I24 of a first peak appearing within a range of 2? from 23.5° to 24.5° is 0.5 or greater, according to X-ray diffraction spectroscopy for the active material.

Abstract: A structure includes: a ? silicon nitride crystal phase; and a Y2MgSi2O5N crystal phase. The structure gives a X-ray diffraction pattern by a ?-2? method, the pattern having a ratio of a peak intensity of a (22-1) plane of the Y2MgSi2O5N crystal phase to a peak intensity of a (200) plane of the ? silicon nitride crystal phase, the peak intensity of the (200) plane being determined at a position of 2?=27.0±1°, the peak intensity of the (22-1) plane being determined at a position of 2?=30.3±1°, and the ratio being 0.001 or more and 0.01 or less.

Abstract: The embodiments provide a radiation detection material emitting fluorescence with high intensity and short lifetime, and also provide a radiation detection device. The polycrystalline radiation detection material of the embodiment is represented by the following formula (1) TlM1-x-yRxX3-z??(1). In the formula, M is at least one metal element selected form the group consisting of Ca, Sr, Ba and Mg; R is at least one luminescence center element selected form the group consisting of Ce, Pr, Yb and Nd; X is at least one halogen element selected form the group consisting of Cl, Br and F; and x, y and z are numbers satisfying the conditions of 0?x?0.5, ?0.1?y?0.1, and ?0.5?z?1, respectively.

Abstract: A structure includes: a ? silicon nitride crystal phase; and a Y2MgSi2O5N crystal phase. The structure gives a X-ray diffraction pattern by a ?-2? method, the pattern having a ratio of a peak intensity of a (22-1) plane of the Y2MgSi2O5N crystal phase to a peak intensity of a (200) plane of the ? silicon nitride crystal phase, the peak intensity of the (200) plane being determined at a position of 2?=27.0±1°, the peak intensity of the (22-1) plane being determined at a position of 2?=30.3±1°, and the ratio being 0.001 or more and 0.01 or less.

Abstract: The embodiments provide a radiation detection material emitting fluorescence with high intensity and short lifetime, and also provide a radiation detection device. The polycrystalline radiation detection material of the embodiment is represented by the following formula (1) TlM1-x-yRxX3-z??(1). In the formula, M is at least one metal element selected form the group consisting of Ca, Sr, Ba and Mg; R is at least one luminescence center element selected form the group consisting of Ce, Pr, Yb and Nd; X is at least one halogen element selected form the group consisting of Cl, Br and F; and x, y and z are numbers satisfying the conditions of 0?x?0.5, ?0.1?y?0.1, and ?0.5?z?1, respectively.

Abstract: According to one embodiment, a structure according to the embodiment includes a ? type silicon nitride type crystal phase and a Y2Si3O3N4 type crystal phase. In an X-ray diffraction pattern according to a ?-2? method of the structure, a ratio of a second peak intensity being maximum and appearing at 2?=31.93±0.1° with respect to a first peak intensity being maximum and appearing at 2?=27.03±0.1° is 0.005 or more and 0.20 or less.

Abstract: The embodiment of the present disclosure provides a phosphor improved in the emission intensity maintenance ratio without impairing the emission intensity. The phosphor is a silicofluoride phosphor and shows an IR absorption spectrum satisfying the conditions of 0?I2/I1?0.01 and 6.7?(I3/I1)/CMn. In those conditional formulas, I1, I2 and I3 are intensities of the maximum peaks in the ranges of 1200 to 1240 cm?1, 3570 to 3610 cm?1 and 635 to 655 cm?1, respectively, and CMn is a weight percent of Mn contained the phosphor.

Abstract: The embodiment of the present disclosure provides a phosphor improved in the emission intensity maintenance ratio without impairing the emission intensity. The phosphor is a silicofluoride phosphor and shows an IR absorption spectrum satisfying the conditions of 0?I2/I1?0.01 and 6.7?(I3/I1)/CMn. In those conditional formulas, I1, I2 and I3 are intensities of the maximum peaks in the ranges of 1200 to 1240 cm?1, 3570 to 3610 cm?1 and 635 to 655 cm?1, respectively, and CMn is a weight percent of Mn contained the phosphor.

Abstract: A light-emitting device of an embodiment includes a light-emitting element emitting blue excitation light and a first phosphor excited by the blue excitation light and emitting fluorescence. A peak wavelength of the fluorescence is not shorter than 520 nm and shorter than 660 nm and the peak wavelength of the fluorescence shifting in the same direction when a peak wavelength of the blue excitation light shifts. The first phosphor is one of a yellow phosphor emitting yellow fluorescence, a green phosphor emitting green fluorescence, a yellow-green/yellow phosphor emitting yellow-green/yellow fluorescence and a red phosphor emitting red fluorescence.

Abstract: A light emitting device according to embodiments includes a light emitting element emitting light with a peak wavelength of 420˜445 nm, a first phosphor emitting light with a peak wavelength of 485˜530 nm, a second phosphor emitting light with a peak wavelength of 530˜580 nm, and a third phosphor emitting light with a peak wavelength of 600˜650 nm. The device emits light having an emission spectrum that has a local minimum value of light intensity between a wavelength of 450˜470 nm or less, the local minimum value being 60% or less of a maximum value of light intensity at a longer wavelength side from the local minimum value, and the device emits light having a color temperature of 4600 K or higher and 5400 K or less.

Abstract: A present embodiment is to provide a phosphor that has favorable temperature characteristics, that can emit yellow light having excellent color rendering properties, and that has high quantum efficiency. The phosphor exhibits a luminescence peak in a wavelength range of 500 to 600 nm when excited with light having a luminescence peak within a wavelength range of 250 to 500 nm. The phosphor is represented by the following formula (1): ((M1-xCe)x)2yAlzSi10-zOuNw (1) (wherein M includes at least one of Ba, Sr, Ca, Mg, Li, Na, and K, and 0<x?1, 0.8?y?1.1, 2?z?3.5, u?1, 1.8?z?u, and 13?u+w?15 are satisfied). The phosphor has a paramagnetic defect density of 5×1015 per gram or less.

Abstract: A present embodiment is to provide a phosphor that has favorable temperature characteristics, that can emit yellow light having excellent color rendering properties, and that has high quantum efficiency. The phosphor emits yellow light when excited with light having a luminescence peak in a wavelength range of 250 to 500 nm and has a crystal structure that is substantially identical to the crystal structure of Sr2Al3Si7ON13. In the average crystal structure of the phosphor determined by Rietveld analysis, the distance between an atom at coordinates corresponding to the first coordinates of Sr, M, or Ce atoms and an atom at coordinates corresponding to the 14th coordinates of O or N atoms is 2.0 to 2.6 ? in a case in which the crystal structure is analyzed, assuming that the crystal structure belongs to a space group Pna21, and is represented using crystal structure data standardization software STRUCTURE TIDY.

Abstract: An embodiment is to provide a phosphor that has favorable temperature characteristics, that can emit yellow light with a wide half-width emission spectrum, and that has high quantum efficiency. The phosphor emits yellow light when excited with light having a luminescence peak in a wavelength range of 250 to 500 nm, and has a crystal structure that is substantially identical to the crystal structure of Sr2Al3Si7ON13. The half-width of a peak at a diffraction peak position 2? in a range of 35.2 to 35.6, detected in X-ray diffraction of the phosphor according to Bragg-Brendano method using a Cu-K? line, is 0.10° or less.

Abstract: The present embodiments provide a europium-activated oxynitride phosphor and a production method thereof. This phosphor emits red luminescence having a peak at 630 nm or longer and can be produced by use of inexpensive oxides as raw materials containing alkaline earth metals such as strontium. The oxynitride phosphor is activated by a divalent europium and represented by the formula (1): (M1-xEux)AlaSibOcNdCe??(1). In the formula, M is an alkaline earth metal, and x, a, b, c, d and e are numbers satisfying the conditions of 0<x<0.2, 1.3?a?1.8, 3.5?b?4, 0.1?c?0.3, 6.7?d?7.2 and 0.01?e?0.1, respectively.

Abstract: A light emitting device according to embodiments includes a light emitting element emitting light having a peak wavelength of 425 nm or more and 465 nm or less, a first phosphor emitting light having a peak wavelength of 485 nm or more and 530 nm or less, a second phosphor emitting light having a peak wavelength longer than that of the first phosphor, and a third phosphor emitting light having a peak wavelength longer than that of the second phosphor. Then, when the peak wavelength of the light emitting element is ?0 (nm) and the peak wavelength of the first phosphor is ?1 (nm), a relation of 30??1??0?70 is satisfied.

Abstract: According to one embodiment, the luminescent material exhibits a luminescence peak in a wavelength ranging from 500 to 600 nm when excited with light having an emission peak in a wavelength ranging from 250 to 500 nm. The luminescent material has a composition represented by Formula 1 below: (M1-xCex)2yAlzSi10-zOuNw??Formula 1 wherein M represents Sr and a part of Sr may be substituted by at least one selected from Ba, Ca, and Mg; x, y, z, u, and w satisfy following conditions: 0<x?1, 0.8?y?1.1, 2?z?3.5, u?1 1.8?z?u, and 13?u+w?15.

Abstract: The embodiment of the present disclosure provides a phosphor exhibiting an emission peak in the wavelength range of 565 to 600 nm under excitation by light having a peak in the wavelength range of 250 to 500 nm. The emission peak has a half width of 115 to 180 nm inclusive. This phosphor has a crystal structure of Sr2Si7Al3ON13, and is activated by cerium.

Abstract: The embodiment of the present disclosure provides a yellow light-emitting phosphor represented by the formula (1): ((SrpM1-p)1-xCex)2yAlzSi10-zOuNw. In the formula, M is at least one of the alkaline earth metals, and p, x, y, z, u and w are numbers satisfying the conditions of 0?p?1, 0<x?1, 0.8?y?1.1, 2?z?3.5, 0<u?1, 1.8?z?u and 13?u+w?15. The emission peak of the phosphor shifts within a range of less than 15 nm when the peak of exciting light is changed in the range of 350 to 475 nm.

Abstract: According to one embodiment, the luminescent material emits light with an emission peak within a wavelength range of 490 to 580 nm when excited with light having a wavelength range of 250 to 500 nm and includes a particle containing a Sr3Si13Al3O2N21-based crystal activated by Eu. The particle includes an outer region which is within a depth of 5 nm from a surface of the particle and an inner region which is deeper than the outer region. The outer region and the inner region satisfy a ratio Oouter/Oinner of 1.0 to 3.8. Oouter is an average of oxygen concentration in the outer region and Oinner is an average of oxygen concentration in the inner region.

Abstract: According to one embodiment, the luminescent material exhibits a luminescence peak in a wavelength ranging from 490 to 580 nm when excited with light having an emission peak in a wavelength ranging from 250 to 500 nm. The luminescent material has a diffraction peak intensity of the largest peak detected at 2?=30.1-31.1° that is higher than the diffraction peak intensity of the peak detected at 2?=25.0-26.0° in X-ray diffraction by the Bragg-Brendano method using Cu-K? line and its composition is represented by (Sr1?xEux)3?yAl3+zSi13?zO2+uN21?w (a part of the Sr may be substituted by at least one selected from Ba, Ca, Mg and Na, 0<x?1, ?0.1?y?0.3, ?3?z??0.52, and ?1.5?u??0.3, ?3<u?w?1).