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Re: Thermionic emission, was Nylon nuts and bolts
Original poster: "Scott Hanson" <huil888@xxxxxxxxxxxx>
Possibly some misunderstanding here .......thermionic emission has
nothing to do with "heat shedding".
Perhaps you are thinking of the "emissivity" of a surface?
Thermionic emission is thermally-induced emission of electrons, the
most familiar usage being in the cathode of vacuum tubes of various
types (CRTs, magnetrons, diodes/triodes/tetrodes/pentodes, etc). The
heated cathode is the internal source of electrons that enables a
flow of current through the tube, or in the case of CRTs the creation
of an electron beam to "write" on the phosphor-coated screen and
create a visible image.
In thoriated tungsten TIG welding electrodes, the thorium oxide is a
source of alpha particles, which helps generate consistent
arc-starting characteristics and helps stabilize the arc once
started. Again, nothing to do with heat shedding.
Regards,
Scott Hanson
----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Tuesday, July 18, 2006 3:23 PM
Subject: Re: Nylon nuts and bolts
Original poster: "" <tesla@xxxxxxxxxxxxxx>>
(snip)
....sort of like using 2% Thoriated Tungsten for the rotary spark gap. I
know that the thoria increases the thermionic
emissions (heat shedding) but if that bad boy is spinning at around 3600
rpm, it's cooling itself!
(snip)
John F. Cooper III
www.Tesla-Coil.com
john@xxxxxxxxxxxxxx