Abstract: A switching optical antenna that includes: a waveguide including a light input end and a light output end; a ring waveguide coupled with the waveguide through a first directional coupler; a diffraction grating that is disposed within the ring waveguide and that is coupled with the ring waveguide through a second directional coupler; and a refractive index adjusting section that changes a refractive index of at least a portion of the ring waveguide.

Abstract: There is provided a nitrided layer repair method in which a molten metal is pressurized and solidified, and thus a nitrided layer formed on a cavity surface of a mold used to form a casting object is repaired. In the nitrided layer repair method, a nitriding source is applied to the cavity surface, and the cavity surface of the mold is nitrided by heating and pressurizing the cavity surface using the molten metal.

Abstract: Provide is a catalytic converter including a substrate which includes regions having different cell densities, in which exhaust gas purification performance is superior in all the regions of the substrate. A catalytic converter 10 includes catalyst layers in which a noble metal catalyst is supported on a support in surfaces of cell walls 2 of a substrate 1 having a cell structure in a longitudinal direction of the substrate 1 in which gas flows, in which the substrate 1 has a first region 1A having a relatively high cell density and a second region 1B having a relatively low cell density, and a ratio of a thickness of a catalyst layer 3A in the second region 1B to a thickness of a catalyst layer 3 in the first region 1A is in a range of more than 0.95 times and 1.2 times or less.

Abstract: A catalyst converter includes: a substrate (1) having a cell structure formed of a center area (1A) having the highest cell density, a peripheral area (1C) having the lowest cell density, and an intermediate area (1B) having the cell density between that of the center area and that of the peripheral area; a first catalyst layer formed in the center area (1A); a second catalyst layer formed in the intermediate area (1B); and a third catalyst layer formed in the peripheral area (1C). A length in a longitudinal direction of the second catalyst layer is longer than that of the first catalyst layer. A length in the longitudinal direction of the third catalyst layer is longer than that of the second catalyst layer. A ratio of the length in the longitudinal direction of the first catalyst layer to the length of the substrate is 65% or more.

Abstract: Provided is a catalytic converter in which the entire catalyst constituting the catalytic converter can be efficiently utilized to purify exhaust gas, and the emission of hydrogen sulfide can be suppressed. A catalytic converter 10 includes catalyst layers 2A, 2B formed of a noble metal catalyst that are formed on cell wall surfaces of a substrate 1 having a cell structure in a longitudinal direction of the substrate 1 in which gas flows, in which the substrate 1 has a center region 1A having a relatively high cell density and a peripheral region 1B having a relatively low cell density, and lengths of the catalyst layers 2A, 2B of the center region 1A and the peripheral region 1B in the longitudinal direction are the same as each other, or the length of the catalyst layer 2B in the longitudinal direction is shorter than that of the catalyst layer 2A.

Abstract: [Task] There is provided a mold release agent for forming a water glass-containing sand mold with high release properties which can prevent attachment of a water glass to a flask and the accumulation of the water glass on the flask in the formation of the sand mold when using the water glass as a binder. [Solution] The mold release agent for forming the water glass-containing sand mold is structured to contain an organic compound, the organic compound having a proton-donating functional group that reacts with the water glass to produce silicon dioxide. The water glass contained in a raw material for the sand mold reacts with the proton-donating functional group contained in the mold release agent so as to produce silicon dioxide. Since silicon dioxide has no adhesion, it can prevent that the attachment (fixing) of the water glass contained in a formed sand mold to the flask and the accumulation of the water glass on the flask.

Abstract: A catalyst converter includes: a substrate (1) having a cell structure formed of a center area (1A) having the highest cell density, a peripheral area (1C) having the lowest cell density, and an intermediate area (1B) having the cell density between that of the center area and that of the peripheral area; a first catalyst layer formed in the center area (1A); a second catalyst layer formed in the intermediate area (1B); and a third catalyst layer formed in the peripheral area (1C). A length in a longitudinal direction of the second catalyst layer is longer than that of the first catalyst layer. A length in the longitudinal direction of the third catalyst layer is longer than that of the second catalyst layer. A ratio of the length in the longitudinal direction of the first catalyst layer to the length of the substrate is 65% or more.

Abstract: A honeycomb structural body is made of cordierite ceramic and composed of partition walls and cells. A cell density is changed continuously or step by step from a central section to an outer peripheral section in a radial direction. The honeycomb structural body has a relationship of M1>M2>M3, and a relationship of K1<K2. M1 is an average cell density of a first section formed from a center to not more than ? R from the center. M2 is an average cell density of a second section formed within a range from ? R to ? R. M3 is an average cell density of a third section formed of more than ? R from the center to an outer peripheral surface. K1 and K2 are average cell density change rates of the first and second sections, respectively. R is a radius of the honeycomb structural body.

Abstract: A honeycomb structural body has plural cell density sections having a cell density which is changed stepwise in a radial direction. A partition wall is formed between adjacent cell density sections. The cell density sections have a high cell density section having a maximum cell density, excepting an outermost cell density section formed at an outermost side, and a low cell density section having a minimum cell density, excepting an innermost cell density section formed at an innermost side. A relationship of V?Va?Vb+Vs is satisfied, where V indicates a volume of the honeycomb structural body if the overall honeycomb structural body is composed of the high cell density section, Va indicates a volume of the high cell density section, Vb indicates a volume of the cell density section, and Vs indicates a volume of the boundary wall which separates the low cell density section from the cell density section formed immediately inside of the low cell density section.

Abstract: A catalytic converter capable of uniformizing an exhaust gas flow velocity to realize uniform temperature distribution and improved purification performance, and a method for designing the catalytic converter. A catalytic converter includes a catalyst base composed of an inner base material part having inner cell holes and an outer base material part having outer cell holes, and an exhaust pipe composed of an upstream-side pipe, a catalyst housing pipe and a downstream-side pipe. In the catalytic converter, a flow path cross-sectional area of the upstream-side pipe defined as S1, a cross-sectional area of the inner base material part defined as S2, a cross-sectional area of the catalyst base defined as S3, a hydraulic diameter of the inner cell holes defined as d1 and a hydraulic diameter of the outer cell holes defined as d2, satisfy the relationship, S1?S2?S3(?0.2242 (d12/d22)2+0.1141 (d12/d22)+0.617).

Abstract: [Task] There is provided a mold release agent for forming a water glass-containing sand mold with high release properties which can prevent attachment of a water glass to a flask and the accumulation of the water glass on the flask in the formation of the sand mold when using the water glass as a binder. [Solution] The mold release agent for forming the water glass-containing sand mold is structured to contain an organic compound, the organic compound having a proton-donating functional group that reacts with the water glass to produce silicon dioxide. The water glass contained in a raw material for the sand mold reacts with the proton-donating functional group contained in the mold release agent so as to produce silicon dioxide. Since silicon dioxide has no adhesion, it can prevent that the attachment (fixing) of the water glass contained in a formed sand mold to the flask and the accumulation of the water glass on the flask.

Abstract: A catalytic converter including: a cell structured first substrate; and a cell structured second substrate provided at a downstream side of the first substrate. The first substrate has a uniform cell density. The second substrate includes a center area with a first cell density and a surrounding area with a second cell density that is lower than the first cell density. The first substrate and the second substrate are mounted in tandem.

Abstract: A catalytic converter (10) includes i) an outer tube (1) that includes a cylindrical portion (1a), an upstream-side cone portion (1b), and a downstream-side cone portion (1c), and ii) a substrate (2) having a cell structure that is arranged in the cylindrical portion (1a) of the outer tube (1). The substrate (2) has a center region (2a) where a cell density is relatively high and a peripheral region (2b) where the cell density is relatively low, in a cross-section that is orthogonal to a length direction of the substrate (2). A projection portion when a connecting portion (5) of the exhaust duct (4) and the downstream-side cone portion (1c) is projected onto the substrate (2) is within the center region (2a).

Abstract: A catalyst converter includes: a substrate (1) having a cell structure formed of a center area (1A) having the highest cell density, a peripheral area (1C) having the lowest cell density, and an intermediate area (1B) having the cell density between that of the center area and that of the peripheral area; a first catalyst layer formed in the center area (1A); a second catalyst layer formed in the intermediate area (1B); and a third catalyst layer formed in the peripheral area (1C). A length in a longitudinal direction of the second catalyst layer is longer than that of the first catalyst layer. A length in the longitudinal direction of the third catalyst layer is longer than that of the second catalyst layer. A ratio of the length in the longitudinal direction of the first catalyst layer to the length of the substrate is 65% or more.

Abstract: Provide is a catalytic converter including a substrate which includes regions having different cell densities, in which exhaust gas purification performance is superior in all the regions of the substrate. A catalytic converter 10 includes catalyst layers in which a noble metal catalyst is supported on a support in surfaces of cell walls 2 of a substrate 1 having a cell structure in a longitudinal direction of the substrate 1 in which gas flows, in which the substrate 1 has a first region 1A having a relatively high cell density and a second region 1B having a relatively low cell density, and a ratio of a thickness of a catalyst layer 3A in the second region 1B to a thickness of a catalyst layer 3 in the first region 1A is in a range of more than 0.95 times and 1.2 times or less.

Abstract: There is provided a catalytic converter that offers high exhaust gas cleaning performance by effectively utilizing a whole catalyst that constitutes the catalytic converter. In a catalytic converter (10), catalytic layers (2A, 2B) made of a noble metal catalyst are formed on cell wall surfaces of a substrate (1) having a cell structure, and the catalytic layers (2A, 2B) extend in a longitudinal direction of the substrate (1) along which gas flows. The substrate (1) has a central region (1A) having a relatively high cell density and a peripheral region (1B) having a relatively low cell density. The length of each of the catalytic layers (2B) in the longitudinal direction in the peripheral region (1B) is longer than the length of each of the catalytic layers (2A) in the longitudinal direction in the central region (1A).

Abstract: Provided is a catalytic converter in which the entire catalyst constituting the catalytic converter can be efficiently utilized to purify exhaust gas, and the emission of hydrogen sulfide can be suppressed. A catalytic converter 10 includes catalyst layers 2A, 2B formed of a noble metal catalyst that are formed on cell wall surfaces of a substrate 1 having a cell structure in a longitudinal direction of the substrate 1 in which gas flows, in which the substrate 1 has a center region 1A having a relatively high cell density and a peripheral region 1B having a relatively low cell density, and lengths of the catalyst layers 2A, 2B of the center region 1A and the peripheral region 1B in the longitudinal direction are the same as each other, or the length of the catalyst layer 2B in the longitudinal direction is shorter than that of the catalyst layer 2A.

Abstract: In a cross section, perpendicular to an axial direction of a honeycomb structural body having partition walls and cells, a plurality of sections having a different cell density is formed from a central area toward an outer peripheral area, and a partition wall is formed between the sections adjacent to each other. The boundary section has boundary partition walls and plural boundary cells having a polygonal shape different in shape from the cells in the sections formed adjacent to the boundary section. The partition walls in the sections adjacent to the boundary section are connected by the boundary partition walls. A part of the boundary cell is surrounded by at least the boundary partition walls. A relationship of ?1/?2?1.25 is satisfied, where ?1 indicates an average hydraulic diameter of the boundary cells and ?2 indicates an average hydraulic diameter of the cells.

Abstract: A catalytic converter including: a cell structured first substrate; and a cell structured second substrate provided at a downstream side of the first substrate. The first substrate has a uniform cell density. The second substrate includes a center area with a first cell density and a surrounding area with a second cell density that is lower than the first cell density. The first substrate and the second substrate are mounted in tandem.

Abstract: A light scanning apparatus including a light source for emitting light in a direction different from a direction orthogonal to the reference direction, and a rotating reflection body that rotates about an axis inclined at an inclination angle ? to the reference direction and includes at least one reflecting surface that is disposed in a direction intersecting obliquely with the axis and reflects light incident on the reflecting surface at an incident angle ?. A specific scanning direction is a direction intersecting at an angle to the reference direction and the rotation axis inclination angle ??0°. The inclination angle ? is predetermined according to the incident angle ? such that deviation of the scanning beam reflected by the reflecting surface is smaller than the deviation of the scanning beam that would be obtained with the inclination angle ? of the rotation axis 0°.