A magneto-caloric thermal diode assembly includes a plurality of thermal stages stacked along an axial direction between a cold side and a hot side. A plurality of magnets is distributed along a circumferential direction within a non-magnetic ring in each of the plurality of thermal stages. Each of the plurality of thermal stages between a cold side thermal stage and a hot side thermal stage is positioned between a respective pair of the plurality of thermal stages along the axial direction. The plurality of magnets of each of the plurality of thermal stages between the cold side thermal stage and the hot side thermal stage is spaced from the non-magnetic ring of one of the respective pair of the plurality of thermal stages along the axial direction and is in conductive thermal contact with the non-magnetic ring of the other of the respective pair of the plurality of thermal stages.

A method of configuring a metamaterial structure comprising a plurality of electrical resonators (110) that support magnetoinductive waves is disclosed. The method comprises: powering at least one of the electrical resonators (110) with an alternating current at an excitation frequency, the at least one powered electrical resonator providing a source of magnetoinductive waves in the structure; adjusting parameters of the metamaterial structure to create constructive interference of one- two- or three-dimensional magnetoinductive waves at one or more target resonators of the electrical resonators (110), to improve power transfer from the at least one powered electrical resonator to the one or more target resonators (110).

A method of configuring a metamaterial structure comprising a plurality of electrical resonators (110) that support magnetoinductive waves is disclosed. The method comprises: powering at least one of the electrical resonators (110) with an alternating current at an excitation frequency, the at least one powered electrical resonator providing a source of magnetoinductive waves in the structure; adjusting parameters of the metamaterial structure to create constructive interference of one- two- or three-dimensional magnetoinductive waves at one or more target resonators of the electrical resonators (110), to improve power transfer from the at least one powered electrical resonator to the one or more target resonators (110).

The present invention concerns, in particular, a method for obtaining a product with magnetocaloric effect from a single piece of material having a magnetic phase transition, the method comprising irradiation of at least one part of the material with ions, the irradiation being carried out with a suitable flux so that, after the irradiation, the material has various magnetic phase transition temperatures in the various parts of the material.

In one embodiment, a permanent magnet includes: a composition expressed by R.sub.pFe.sub.qM.sub.rCu.sub.sCo.sub.100-p-q-r-s (R is a rare-earth element, M is at least one element selected from Zr, Ti, and Hf, 10p13.5 at %, 25q40 at %, 1.35r1.75 at %, and 0.88s13.5 at %); and a metallic structure including Th.sub.2Zn.sub.17 crystal phases each having a Fe concentration of 25 at % or more, and Cu-rich crystal phases each having a Cu concentration of from 25 at % to 70 at %. An average thickness of the Cu-rich crystal phases is 20 nm or less, and an average distance between the Cu-rich crystal phases is 200 nm or less.

In one embodiment, a permanent magnet includes: a composition expressed by R.sub.pFe.sub.qM.sub.rCu.sub.sCo.sub.100-p-q-r-s (R is a rare-earth element, M is at least one element selected from Zr, Ti, and Hf, 10p13.5 at %, 25q40 at %, 1.35r1.75 at %, and 0.88s13.5 at %); and a metallic structure including Th.sub.2Zn.sub.17 crystal phases each having a Fe concentration of 25 at % or more, and Cu-rich crystal phases each having a Cu concentration of from 25 at % to 70 at %. An average thickness of the Cu-rich crystal phases is 20 nm or less, and an average distance between the Cu-rich crystal phases is 200 nm or less.

The present invention provides a magnetic multilayer pigment flake and a magnetic coating composition that are relatively safe for human health and the environment. The pigment flake includes one or more magnetic layers of a magnetic alloy and one or more dielectric layers of a dielectric material. The magnetic alloy is an iron-chromium alloy or an iron-chromium-aluminum alloy, having a substantially nickel-free composition. The coating composition includes a plurality of the pigment flakes disposed in a binder medium.

The present invention provides a magnetic multilayer pigment flake and a magnetic coating composition that are relatively safe for human health and the environment. The pigment flake includes one or more magnetic layers of a magnetic alloy and one or more dielectric layers of a dielectric material. The magnetic alloy is an iron-chromium alloy or an iron-chromium-aluminum alloy, having a substantially nickel-free composition. The coating composition includes a plurality of the pigment flakes disposed in a binder medium.

The present invention relates to a method for preparing a magnetic iron oxide-graphene composite, a magnetic iron oxide-graphene composite prepared thereby and a composition for electromagnetic wave shielding including the same, and since graphene is prepared from a stage 1-GIC using FeCl.sub.3, magnetic particles in the form of FeO.sub.x are naturally formed on the surface of graphene during the preparation process. In addition, a magnetic material is formed on the surface of graphene while the defects of graphene are minimized, and thus the magnetic iron oxide-graphene composite prepared according to the present invention can be useful as an electromagnetic wave absorber.

The present invention relates to a method for preparing a magnetic iron oxide-graphene composite, a magnetic iron oxide-graphene composite prepared thereby and a composition for electromagnetic wave shielding including the same, and since graphene is prepared from a stage 1-GIC using FeCl.sub.3, magnetic particles in the form of FeO.sub.x are naturally formed on the surface of graphene during the preparation process. In addition, a magnetic material is formed on the surface of graphene while the defects of graphene are minimized, and thus the magnetic iron oxide-graphene composite prepared according to the present invention can be useful as an electromagnetic wave absorber.