From: hionsolar@aol.com (Hion solar)
Newsgroups: sci.physics.plasma
References: <8847vg$ho0$1@jupiter.cs.uml.edu>
Organization: AOL http://www.aol.com
Subject: Re: Plasma Quench Technology

Hoping,

Your detailed response intrigues me. We have been using the expansion of a jet
of hot gases [H + O + H2O + OH + O2+ H2 + some ionized species] to quench
recombination. Ahead of the nozzle, upstream, there is concentrated sunlight
and water vapor [2-100 Torr] subjected to a glow discharge. Downstream, after
quenching, a skimmer is used to affect some separation into lighter and heavier
fractions. The object is to produce H2 and O2 from water.

We have looked at the emission spectrum of the water vapor glow discharge
without sunlight and see many UV lines. I'm wondering how you determined that
the fast recombination of the ions to form the neutrals or molecules produced
"non-equilibrium densities in the excited electronic states" ? What kind of
instrumentation?

I've never seen a deep blue hydrogen jet.......yet. It sounds like a beautiful
sight! How much energy were you dissipating in the Pashen arc-jet? Was it
exhausting to atmosphere with pressure ratio > choked flow at inlet? Just H2
gas feed?

If the electrons were still heating up the gas molecules as they exited the jet
and went through the transition region and dropped to sub-sonic velocity, maybe
a possitive-grid in the flow field could have stopped the downstream heating
affect [to rule that out]?

Maybe you would be kind enough to comment on our work that has been published
in 1996 in IECEC. You can see the paper on our web-site: WWW.HIONSOLAR.COM
It is called Solar Thermal Hydrogen Production Paper on bottom of Home Page.

I am particularly interested in your comments about the H(-) ion and postulated
chain reactions using this ion to dissociate water in the excited state by
electron donation. We would like to have a way to "see" this ion in the
reaction flow-field and in the "afterglow" region where the separation occurs.

Thanks and Regards....Walt Pyle

>Subject: Re: Plasma Quench Technology
>From: "hoping" Hoffmann.Win@t-online.de
>Date: 02/12/2000 10:15 AM Pacific Standard Time
>Message-id: <8847vg$ho0$1@jupiter.cs.uml.edu>
>
>
>Hi Walt:
>
>I did this work VERY long ago and to my knowledge nobody has resumed since
>then. The idea was to use an effect in analogy to the gasdynamic CO2 laser
>principle, which was quite new in those days. (Now you have an impression
>how long ago this was!) We (me and my collegues) knew, that very rapid
>cooling of a quasi fully ionised plasma in equilibrium leads to
>non-equilibrium densities in the excited electronic states of the neutral
>atom or molecule, because of the fast recombination of the ion. If
>collisional and radiation processes are within certain ranges, even
>population inversion should occur. In some cases very high laser power at
>comparably short wavelenghts should be possible. This was a result of the
>theory. In the beginning it was calculated for hydrogen because it's the
>simplest system and the rate coefficients were reatively well known - in
>contrast to other gases. Although I knew that the H term scheme was not
>necessarily the optimum I spent about two years to try making a high power
>CW! hydrogen laser in the near infrared (Paschen). Have you ever seen a deep
>blue hydrogen jet? It's a beautiful sight. It was created by supersonic
>expansion of an arc discharge in a device originally destined for electric
>propulsion in space. It finally turned out, that at electron densities, high
>enough to produce a substantial optical gain in the direction perpendicular
>to the jet, in contrast to the (simple) theory the cooling was not rapid
>enough to produce population inversion at all. Or in other words: The blue
>jet with population inversion was too thin. Or the device was too small
>respectively. I am quite shure that in the atmospheres of some stars there
>may exist sometimes the conditions for a natural laser with only one pass.
>The reason for the failure? I still know it not for shure, because my
>interest turned to other more short therm promising laser research subjects,
>but I think that from the point of view of an electron with high (runaway)
>speed, the gas velocity was deep in the subsonic region, so that high energy
>electrons could still heat up the plasma all the way down the jet.
>Furthermore all the zoo of plasma waves could have had heating capability.
>The only way to simply overcome this problem was to leave the idea to
>separating plasma production and decay by some distance in space, but to do
>just the same thing in time, that means to look in the afterglow of a
>decaying pulsed plasma. That's what a lot of people did later with
>remarkable results. One of the first was Silvfast at the Bell Labs, and a
>lot of work was also done in Russia. Later then the principle was extended
>successfully to higher ionised species to obtain UV, XUV and so on.... But I
>am still hoping (sic!) that someone will construct the CW plasmadynamic
>hydrogen laser. Perhaps you?
>
>Regards Hoping
>