The clear span of a bridge is the gap from the near edge of the next. 桥梁的净跨,是自一个桥墩的近侧边到相邻桥墩近侧边之间的间距。
The ion conductance between the two electrodes changes with the gap between the micro pipette tip and the sample surface. 由于微滴管与基板间离子电导随两者间距减少而减小,采用反馈系统可保持这一间距恒定。