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thermionic

thermionic

3 9.9
Electrons leave a metal surface when it is hot, usually in a vacuum
  • adjective
  • /ˌθɜrˈmiːɒnɪk/
  • Specialized
translation icon : termiónico
  • When heated to high temperatures, the thermionic effect can significantly increase electrical conductivity.
  • thermionic radiation

I would remind you that Tommy Flowers decision with Max Human to build Colossus out of thermionic valve.

Examples

  • The scientist explained how thermionic materials release electrons when heated in a vacuum.

  • Who has seen a thermionic tube?

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  • Did you ever have a chance to read my paper on thermionic transconductance?

  • This would put 100 mA through the filament and should cause the thermionic emissions we need.

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  • We just need to test if the only thing missing here is the thermionic emission to make the display work, so the DC test is fine.

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  • Thermionic radio valves.

  • So this uses a a so-called thermionic cathode where there's a tungsten filament thinner that gets very hot.

  • It seems the radio has a dead heater driver for the cathode filament, which should be producing the thermionic emission of electrons needed to cause the fluorescent tracks to fluoresce.

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  • The thermionic emission is essential for the operation of vacuum tubes in electronic devices.

Compounds

thermionic current
  • Specialized
9.7

An electric flow between two metal parts caused by heat making electrons leave one part

9.9

An electronic device in a sealed glass tube that controls electric current in old radios

thermionic emission
  • Specialized
9.1

Electrons escape from a hot metal surface

thermionic tube
  • Archaic
9.8

A glass or metal device that controls the flow of electricity in old radios and machines

A glass or metal tube that uses heat to make electricity flow without air

Surface Forms

thermionic positive

Morphology

thermionic = thermion (semi-transparent) = thermion + ic

Formed from the technical noun 'thermion' + adjective suffix '-ic'; the heat-related element and '-ic' are clear but the specialized sense of 'thermion' is likely unknown to average learners.

Etymology

Thermionic starts with therm- meaning 'heat', the same root in thermal and thermometer, and includes ion, a word for a 'charged particle'. So thermionic literally means 'heat-caused particle', which explains why it describes electrons that come out of a hot source.