Archival storage

[jpero at sympatico.ca]

> Reply-to:      "General Discussion: On-Topic and Off-Topic Posts"
>                <cctalk at classiccmp.org>

> > 
> > > An interesting proposition.  Does plastic still out-gas even if it's
> > > vacuum-packed?
> > 
> > Probably faster. I would think a helium environment would be better, but I
> > am no chemist.
> 
> I would tend to agree. The lower the external pressure (e.g. by vacuum 
> packing), the more likely things are to outgas.
> 
> The problem with helium is that the atom is so small that it will difuse 
> though just about anything. This is a problem with some HeNe laser tubes 
> which lose their helium over time. Perhaps one of the heavier intert 
> gases would be suitable for packing plastics, but I am not sure it would 
> do that much good.
> 
> -tony

Gas of choice and very cheap is nitrogen gas.  Large enough molecules 
not to "diffuse through" and neutral.

In fact, air we beathe is 80% nitrogen, 20% oxygen, traces of other 
noble gases.

This is another reason for a need to have EGR to cut down on NOX 
emissions in most engines that could run hot enough to recombine 
nitrogen with others into NOX which is a pollution.  EGR lowers the 
fire chambers temps enough to cut down on NOX lot.

Cheers, Wizard