Abstract: A motor, a compressor and a refrigeration device are provided. The motor includes a stator and a rotor. The stator has a central hole and multiple stator slots arranged in an annular array centered on an axis of the central hole. The rotor is provided in the central hole. Multiple rotor slots are provided on the rotor, and are arranged in an annular array centered on the axis of the central hole and close to an edge of the rotor. A plane perpendicular to the axis of the central hole is a reference plane, a sum of projected areas of the stator slots on the reference plane is S1, a sum of projected areas of the rotor slots on the reference plane is S2, an outer periphery of the stator projected on the reference plane forms a projected pattern, and an area of the projected pattern is S3.

Abstract: A variable flow heat exchanger may include a housing and a heat exchange core. The housing may include a first housing and a second housing. The heat exchange core may be arranged between the first housing and the second housing. The heat exchange core may be formed by superposition of multi-layer heat exchange plates. A cooling fluid interface may be arranged on the first housing. A cooled fluid interface may be arranged on the second housing. The cooled fluid interface may include a first interface, a second interface, and a third interface. In a first state, a cooled fluid may flow into the heat exchange core from the first interface and may flow out of the second interface. In a second state, the cooled fluid may flow into the heat exchange core from the first interface and the second interface, respectively, and may flow out of the third interface.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures, and a cold collection system comprising a plurality of the polymer-based selective radiative cooling structures.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures.

Abstract: A grain boundary diffusion method for a bulk rare earth permanent magnetic material includes the following steps: (1) fabricating an initial magnet by a sintering, hot pressing, or hot deformation process; (2) loading a grain boundary diffusion alloy source on a surface of the magnet through electrodeposition, chemical vapor deposition (CVD), physical vapor deposition (PVD), direct physical contact, or adhesive bonding; and (3) placing the initial magnet loaded with the grain boundary diffusion alloy source in a SPS device, and heating to obtain a final magnet. The current, plasma, and pressure in an SPS process can be controlled to significantly improve elemental diffusion coefficient and enhance the diffusion depth. The bulk rare earth permanent magnetic material undergoing grain boundary diffusion fabricated in the present disclosure has a significant increase in magnetic properties that catering to commercial demands for industrial production.

Abstract: A motor, a compressor and a refrigeration device are provided. The motor has a stator and a rotor. The stator has an annular stator yoke and multiple stator teeth located on an inner side of the stator yoke. The stator teeth are provided at intervals along a periphery of the stator yoke. The rotor is provided in the stator. The rotor has an annular rotor yoke and multiple rotor teeth located on an exterior of the rotor yoke. The rotor teeth are provided at intervals along a periphery of the rotor yoke. A tooth width of the stator teeth is T1 and a width of the stator yoke is T2, and T1 and T2 are defined by 4.8?T2/T1?5.1. A tooth width of the rotor teeth is L1 and a width of the rotor yoke is L2, and L1 and L2 are defined by 6.1?L2/L1?6.3.

Abstract: A motor, a compressor and a refrigeration device are provided. The motor includes a stator and a rotor. The stator has a central hole and multiple stator slots arranged in an annular array centered on an axis of the central hole. The rotor is provided in the central hole. Multiple rotor slots are provided on the rotor, and are arranged in an annular array centered on the axis of the central hole and close to an edge of the rotor. A plane perpendicular to the axis of the central hole is a reference plane, a sum of projected areas of the stator slots on the reference plane is S1, a sum of projected areas of the rotor slots on the reference plane is S2, an outer periphery of the stator projected on the reference plane forms a projected pattern, and an area of the projected pattern is S3.

Abstract: A motor and a compressor having the motor are provided. The motor has a stator and a rotor. The stator has a circular tubular stator core having an inner diameter and an outer diameter. The ratio k of the inner diameter to the outer diameter satisfies k>0.5. The rotor is provided in the cylindrical space formed by the stator core and has a rotor core and a magnetic member provided on the rotor core. The exhaust volume V of the compressor, the mass M of the rotor core and the magnetic member, and the maximum radius of an outer edge of the rotor satisfy 2<V/(M*R2)*1000<4. The motor reduces speed fluctuation while ensuring motor miniaturization, effectively improves the operational stability of the compressor in the low-frequency operation process of the compressor, increases the machine efficiency of the compressor, and reduces the compressor noise.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures.

Abstract: The present invention relates to the field of prevention of a water disaster in coal mining, and discloses a risk evaluation method of an overburden bed-separation water disaster in a mining area. In the prior art, prevention of the bed-separation water disaster is achieved mainly by making bed-separation water “cut-off holes” and “diversion holes” underground; however, the degree of a roof bed-separation water disaster in the mining area has not yet been qualitatively or quantitatively evaluated and analyzed, resulting in blindness of the prevention of the bed-separation water disaster. In order to solve this problem, the present invention provides a risk evaluation method of an overburden bed-separation water disaster in a mining area, which includes the following steps: S1. collecting geological information about strata in the mining area; S2. calculating the height of a water-conducting fissure zone in the mining area; S3.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures.

Abstract: The present application discloses a method for fabricating ceramic insulator for electronic packaging, and relates to a technical field of outer shell packaging of electronic devices. Under the circumstance of using neither a chemical coating nor any bonding wire connection circuit, through a design that builds a electroplated circuit into the ceramic insulator, the method accomplishes coating of a nickel alloy protection layer onto a porcelain by an electroplating method, so that not only quality of a coating layer but also requirement of a complete appearance can be ensured. All circuits of the ceramic insulator fabricated by the aforesaid method can conduct with external circuits, such that the electroplating method can be used to accomplish coating of the nickel alloy layer, after accomplishment of all metal coating, metallization parts on an end surface of the porcelain is removed.

Abstract: The present application discloses a method for fabricating ceramic insulator for electronic packaging, and relates to a technical field of outer shell packaging of electronic devices. Under the circumstance of using neither a chemical coating nor any bonding wire connection circuit, through a design that builds a electroplated circuit into the ceramic insulator, the method accomplishes coating of a nickel alloy protection layer onto a porcelain by an electroplating method, so that not only quality of a coating layer but also requirement of a complete appearance can be ensured. All circuits of the ceramic insulator fabricated by the aforesaid method can conduct with external circuits, such that the electroplating method can be used to accomplish coating of the nickel alloy layer, after accomplishment of all metal coating, metallization parts on an end surface of the porcelain is removed.

Abstract: Polymer-based selective radiative cooling structures are provided which include a selectively emissive layer of a polymer or a polymer matrix composite material. Exemplary selective radiative cooling structures are in the form of a sheet, film or coating. Also provided are methods for removing heat from a body by selective thermal radiation using polymer-based selective radiative cooling structures.