Re: Thermionic emission, was Nylon nuts and bolts

["Tesla list" <tesla@xxxxxxxxxx>]

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