Quality Control: Ensure that materials meet the desired specifications by verifying particle size distributions. 知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。 Nominal size of aperture - The nominal aperture size determines the wire spacing. There is a nominal aperture size on each side of the rectangle. According to the I.P., mesh apertures are measured https://notes.io/wPz6p