L'Affaire Siloxane
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L'Affaire Siloxane
1–10 of 59 posts
Re: L'Affaire Siloxane
#2Siloxanes contaminate everything. We routinely see them on various surfaces when doing X-ray photoelectron spectroscopy.
Re: L'Affaire Siloxane
#3> while a further 7,000 kilograms of treated urine were sitting in orbital storage tanks, waiting to be processed.
Is that a record for the biggest piss bottle ever made?
Re: L'Affaire Siloxane
#4I hope to see these seemingly mundane unknown unknowns raised in space travel centered hard science fiction. I think The Martian and Seveneves almost captured these but not quite.
Re: L'Affaire Siloxane
#5Siloxanes contaminate everything. We routinely see them on various surfaces when doing X-ray photoelectron spectroscopy.
Indeed. "Grease peaks" we called them, they were always there in basically all NMR or MS spectra I took as an organic chemist. Like PFAS or microplastics, you just can't get rid of them.
Re: L'Affaire Siloxane
#6I'm sceptical of the claim that they couldn't eliminate the majority of them from stuff that's shipped up to the ISS. Even if it meant making special space certified hair conditioner.
Re: L'Affaire Siloxane
#7An interesting substory that is simultaneously reminiscent of the Fogbank story and how Hayek's "curious task" is much more broadly applicable:
There is a good cautionary tale here from the Space Shuttle era. That vehicle
had heat resistant tiles that had to be attached to the aluminum belly of the
orbiter. A special cloth had been certified for wiping the aluminum clean
before applying the primer that securely bonded the tiles to the metal. After
years of uneventful use, tile engineers discovered that new replacement tiles
were no longer curing properly.
A careful investigation revealed that the supplier of that special cloth had
changed the lubricant used in the machine that sews its hem. Minute amounts
of the lubricant were being deposited on the stitching, and enough of that
residue was getting on the aluminum skin to prevent the tile adhesive from
curing properly.Re: L'Affaire Siloxane
#8Part of my job is to keep siloxanes out of a complex, multi-step, multi-sub-contracted manufacturing process. A supplier change that should have been a simple affair has cost us several kilobucks in analyses in the past months. I hate the stuff.
Re: L'Affaire Siloxane
#9I'm sceptical of the claim that they couldn't eliminate the majority of them from stuff that's shipped up to the ISS. Even if it meant making special space certified hair conditioner.
I don't see why not either, just get "organic"/plant or mineral based cosmetics, deodorants and hair products.
Re: L'Affaire Siloxane
#10An interesting substory that is simultaneously reminiscent of the Fogbank story and how Hayek's "curious task" is much more broadly applicable: There is a good cautionary tale here from the Space Shuttle era. That vehicle had heat resistant tiles that had to be attached to the aluminum belly of the orbiter. A special cloth had been certified for wiping the aluminum clean before applying the primer that securely bonde…
In medical device manufacturing you have systems in place that your vendors have to disclose changes to their manufacturing process that hopefully can catch stuff like this before people die. I can see how minute stuff gets easily passed off as not an important change.