When primary electrons hit the surface of the chunnel, secondary electrons are generated, which make the electron distribution at the exit hole of the chunnel more uniform.是什么意思_When primary electrons hit the surface of the chunnel, secondary electrons are generated, which make the electron distribution at the exit hole of the chunnel more uniform.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句