在边界和半边界区内,摩擦随纤维表面粗糙度的增加而增加.Friction increases with increasing fiber surface roughness in the boundary and semiboundary.小规模的粗糙度涉及到颗粒边缘和破坏表面.This roughness occurs on a small scale, involving grain boundaries and failure su...
从该星系中心收到的无线电信号证实了黑洞理论。Radio signals received from the galaxy's centre back up the black hole theory.他们发现了以往想象不到的新客体 —— 脉冲星 、 类星体和黑洞.They have discovered now , previou sly unimagined objects - pulsars, quasars, and b...