Abstract: A magnetic refrigerating device includes: a magnetic refrigerating unit including a magnetic material “A” exhibiting a magneto-caloric effect that the temperature of the material “A” is increased by the application of a magnetic field and the temperature of the material “A” is decreased by the removal of a magnetic field, a magnetic material “B” exhibiting a magneto-caloric effect that the temperature of the material “B” is decreased by the application of a magnetic field and the temperature of the material “B” is increased by the removal of a magnetic field, a heat conductive material “a” exhibiting higher heat conductivity under the application of a magnetic field and lower heat conductivity under the removal of a magnetic field, and a heat conductive material “b” exhibiting lower heat conductivity under the application of a magnetic field and higher heat conductivity under the removal of a magnetic field, wherein the magnetic refrigerating unit is configured so as to include at least one layered structure

Abstract: A magnetic material for magnetic refrigeration has a composition represented by (R11-yR2y)xFe100-x (R1 is at least one of element selected from Sm and Er, R2 is at least one of element selected from Ce, Pr, Nd, Tb and Dy, and x and y are numerical values satisfying 4?x?20 atomic % and 0.05?y?0.95), and includes a Th2Zn17 crystal phase, a Th2Ni17 crystal phase, or a TbCu7 crystal phase as a main phase.

Abstract: A magnetic refrigeration material has magnetic material particles with a magnetocaloric effect and an oxidation-resistant film formed on the surfaces of the magnetic material particles.

Abstract: A powder raw material is prepared by mixing at least two kinds of powders selected from a powder A, a powder B, a powder C, and a powder D. A sintered body of a magnetic material having an NaZn13 crystal structure phase is formed by heating the powder raw material while applying a pressure treatment. The powder A is at least one of elemental powder of element R selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. The powder B is at least one of elemental powder of element T selected from Fe, Co, Ni, Mn, and Cr. The powder C is at least one of elemental powder of element M selected from Si, B, C, Ge, Al, Ga, and In. The powder D is a compound powder composed of at least two kinds of elements selected from the element R, the element T, and the element M.

Abstract: A magnetic refrigerator has a housing, heat exchangers filled with magnetic particles having a magnetocaloric effect, a rotary drive, a rotating shaft, a magnetic field generator fixed to the rotating shaft which applies a magnetic field to or eliminates a magnetic field from the magnetic particles in the heat exchangers following rotation of the rotating shaft, a refrigerant pump which circulates the refrigerant following rotation of the rotating shaft, a rotary refrigerant control valve which controls supply of the refrigerant to and discharge of the refrigerant from the heat exchangers following rotation of the rotating shaft, and a refrigerant circuit. The magnetic field generator and the rotary refrigerant control valve are configured to synchronize application of the magnetic field to or elimination of the magnetic field from the magnetic particles with supply of the refrigerant to or discharge of the refrigerant from the heat exchangers.

Abstract: A magnetic material comprising a NaZn13 type crystal structure with uniform and fine microstructure exhibiting excellent characteristics as a magnetic refrigeration material, and a method of manufacturing the magnetic refrigeration material are provided. An alloy composition for forming magnetic material of the NaZn13 type crystal structure was melted comprising 0.5 atomic percent to 1.5 atomic percent of B to molten metal. The molten metal is rapidly cooled and solidified by a forced cooling process. Then, a rapidly cooled alloy having the NaZn13 type crystal structure was obtained. In this manner, magnetic materials comprising the NaZn13 type crystal structure phase, or the NaZn13 type crystal structure phase accompanied with other phases such as ?-Fe phase having very small phase regions was manufactured without requiring heat treatment for a long time. As the result, productivity of manufacturing the magnetic refrigeration material is remarkably enhanced.

Abstract: A heterojunction bipolar transistor having a ballast resistance layer between an AlGaAs emitter layer and an emitter electrode, wherein the ballast resistance layer comprises n-AlxGa1−XAs, wherein 0<X<1, and a GaAs selective etching layer is provided between the emitter layer and the ballast resistance layer.

Abstract: In the case where ohmic electrodes are formed on a semiconductor wafer, first of all, an insulating layer is formed on the semiconductor wafer, then a resist layer is formed on the insulating layer. Next, apertures for forming electrodes are formed in first regions of the resist layer corresponding to regions where the electrodes are formed, while dummy apertures are also formed in a second region of the resist layer in a rest part other than the first regions. Thereafter, the insulating layer is etched using the resist layer as a mask. With the resist layer remaining, electrode material is accumulated on the surface of the semiconductor wafer, and thereafter, the resist layer is removed. As a result, electrodes with desirable ohmic characteristics are stably formed.

Abstract: vertical power MOSFET which comprises a semiconductive substrate of a first conductivity type serving as drain, an impurity region of a second conductivity type on a part of the surface of the semiconductive substrate, an impurity region of a first conductivity type formed on a part of the surface of the second conductivity type impurity region and serving as source, and a surface portion of a second conductivity type semiconductive substrate between source and drain serving as a channel portion with a gate electrode thereon through an insulating film, so that voltage is applied to the gate electrode to control channel current between source and drain, wherein the first conductivity type semiconductive substrate comprises a low resistivity layer and a high resistivity layer epitaxially formed on the low resistivity layer, and at an interface between the low resistivity layer and the high resistivity layer is provided a convexed portion which projects at least to the high resistivity layer side.