单词	thermion
释义	thermion /ˈθəːmɪɒn / noun An ion or electron emitted by a substance at high temperature.Alloyed thorium enhances the emission of thermions by lowering the work function barriers.... When the main power supply of the X-ray tube is on, the cathode emits thermions as it is heated by a heater. Another theory is that, since energy is required to extract electrons from the heated material, there should be cooling when thermions are emitted. Origin Early 20th century: from thermo- 'of heat' + ion.
随便看	signal detection signalee signaletic signal generator signal intelligence signalisation signalise signalist signalization signalize signallee signaller signal light signal line signally signalman signalment signal molecule signal/noise ratio signal pad signal peptide signal plate signal post signal reaction signal red

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