()可使零件表面的凸峰被逐渐磨平,以增大配合面积,减小接触应力,提高零件承载能力,从而降低磨损速度,延长使用寿命。

A、对于生态系统和产业系统，能量都从最低营养级流入 Energy flows into both ecosystems and industrial systems from the lowest trophic level
B、对于生态系统和产业系统，能量都从任何“营养级”流入 Energy may flow into ecosystems and industrial systems from any trophic level
C、能量从生态系统中的最低营养级流入，而产业系统可从任何“营养级”流入 Energy flows into ecosystems from the lowest trophic level while into industrial systems from any trophic levels
D、能量从产业系统中的最低营养级流入，而生态系统可从任何“营养级”流入 Energy flows into industrial systems from the lowest trophic level while into ecosystems from any trophic levels