Abstract: A polymer ultrafiltration membrane with a bicontinuous highly interconnected porous structure, a preparation method and applications thereof are provided. The ultrafiltration membrane has a bottom layer and a polymer layer. The polymer layer is divided into a sublayer and a surface layer. The surface layer is of a uniform small pore structure with a narrow pore size distribution. The sublayer is of a bicontinuous highly interconnected three-dimensional network porous structure. The bicontinuous highly interconnected porous structure of the bicontinuous highly interconnected porous ultrafiltration membrane is characterized as follows: in the thickness direction of the sublayer, the cross-sectional porosity on any XY cross-section perpendicular to the thickness direction is 40-90%, preferably 60-90%, and further preferably 70-90%; and the difference in the cross-sectional porosities between any two XY cross-sections does not exceed 10%, preferably not exceed 8%, and also preferably not exceed 5%.

Abstract: Embodiments of the present application provide an insulation and heat radiation structure of a power device, a circuit board, and a power supply apparatus. The insulation and heat radiation structure of the power device includes a power device, an insulation ceramic piece, and a heat radiator, where the power device is of a sheet structure, the insulation ceramic piece is an alumina ceramic piece, a heat radiator pin is disposed on the heat radiator, the heat radiator pin is used for being mechanically connected to the circuit board, a heating surface of the power device is adhesively fixed to one surface of the insulation ceramic piece through a first insulating thermal conductive adhesive, and the other surface of the insulation ceramic piece is adhesively fixed to a contact heat radiation surface of the heat radiator through a second insulating thermal conductive adhesive.