普通单排优化排样中冲裁步距的计算非常关键.It is critical calculating blanking step in normal single row optimum layout.文章介绍一种在普通冲床使用并能快速、准确改变步距的自动送料机构.In this paper an automatic feed mechanism with changing step is introduced.所以, 宽距的双矮星系统应该极...
随着年龄的增加，人在消耗体力时心脏的输血能力和输血速度会有所减弱。Age diminishes the heart's ability to pump harder and faster under exertion.交感神经纤维分布于心脏的所有部分.Sympathetic fibers are distributed to all regions of the heart.心脏的功能是把血液输往全身.The function...