If the electron flow takes place in a vacuum, as in the case of electronic valve, the electrons will travel at considerable speed, since little resistance is offered the medium.
如果电子在真空里流动，比如电子真空管，那么电子的运行速度非常快，因为介质对电子几乎不产生什么阻力。
2
In order to identify the dominant species in Han-jiang diatom, the micrograph and the valve picture under electron microscope of the dominant species was investigated.
Both the Kondo resonance and the spin-splitting of the single electron levels can be controlled by internal magnetization of the electrodes, which can be used to generate a spin-valve effect.