Abstract: Disclosed is a method for preparing a low erucic acid fragrant rapeseed oil. The method includes subjecting a double low rapeseed to aroma-generating treatment, to obtain an aroma-generated rapeseed, the double low rapeseed including lower than 3 wt % of erucic acid, lower than 45 ?mol/g of total glucosinolates, 6-15 ?mol/g of 3-butenyl glucosinolate, and 0.4-2.0 ?mol/g of 4-methylthiobutyl glucosinolate; mechanically squeezing the aroma-generated rapeseed, to obtain a crude oil; and degumming the crude oil, to obtain the low erucic acid fragrant rapeseed oil.

Abstract: The present application provides a method for manufacturing a printed circuit board and a printed circuit board. The method for manufacturing a printed circuit board includes: providing a core board, wherein the core board includes an insulating baseplate, and a first surface and/or a second surface opposite to the first surface of the insulating baseplate is provided with a plurality of pads; and laminating a medium layer on a side of the insulating baseplate provided with the plurality of pads to form a laminated layer at least partially embedded among the plurality of pads.

Abstract: Embodiments of this application disclose a network topology display method and a communication apparatus, to improve availability and a visualization effect of a network management and control system. The method in embodiments of this application includes: A communication apparatus obtains a multi-level subnet topology structure, determines a subnet density of a first network element based on a layout setting of a user for a physical position of a subnet of the first network element in the multi-level subnet topology structure, and then determines a current scale based on a zoom operation performed by the user on a display area; and when a product of the scale and the subnet density is greater than a preset value, the communication apparatus expands the subnet of the first network element.

Abstract: The main technical problem solved by the present disclosure is to provide a circuit board preparation method. The method includes: obtaining a to-be-processed plate comprising an insulating layer, a first copper layer, a second copper layer opposite to the first copper layer, a blind metalized hole, and a first tab facing the blind metalized hole; obtaining a white insulating material; laminating the white insulating material to a surface of the insulating layer, a surface of the first copper layer, a surface of the first tab, and a surface of the second copper layer to form a first white insulating medium layer and a second white insulating medium layer opposite to the first while insulating medium layer; and performing surface polishing for the first white insulating medium layer and grinding the first white insulating medium layer until the first tab is exposed to form a first white reflective layer.

Abstract: Disclosed are a circuit board and its preparation method. The circuit board includes a base layer, a transmission wire layer including multiple conductor tabs, and an insulating and thermally conductive layer including multiple thermally conductive portions. A gap is defined between each adjacent two of the multiple conductor tabs to expose at least a portion of the base layer, and the gap is filled with a corresponding thermally conductive portion. A height of the thermally conductive portion is larger than heights of each adjacent two of the multiple conductor tabs to define a connection groove. The circuit board the disclosure providing enhances heat dissipation performance of circuit boards.

Abstract: The main technical problem solved by the present disclosure is to provide a circuit board preparation method. The method includes: obtaining a to-be-processed plate comprising an insulating layer, a first copper layer, a second copper layer opposite to the first copper layer, a blind metalized hole, and a first tab facing the blind metalized hole; obtaining a white insulating material; laminating the white insulating material to a surface of the insulating layer, a surface of the first copper layer, a surface of the first tab, and a surface of the second copper layer to form a first white insulating medium layer and a second white insulating medium layer opposite to the first while insulating medium layer; and performing surface polishing for the first white insulating medium layer and grinding the first white insulating medium layer until the first tab is exposed to form a first white reflective layer.

Abstract: The present application provides a method for manufacturing a printed circuit board and a printed circuit board. The method for manufacturing a printed circuit board includes: providing a core board, wherein the core board includes an insulating baseplate, and a first surface and/or a second surface opposite to the first surface of the insulating baseplate is provided with a plurality of pads; and laminating a medium layer on a side of the insulating baseplate provided with the plurality of pads to form a laminated layer at least partially embedded among the plurality of pads.