Groups > sci.electronics.design > #519217

Re: various OTs

From	"Tim Williams" <tiwill@seventransistorlabs.com>
Newsgroups	sci.electronics.design
Subject	Re: various OTs
Date	2018-10-13 21:39 -0500
Organization	A noiseless patient Spider
Message-ID	<ppua8g$s1$1@dont-email.me> (permalink)
References	<r2u1sddojvr815ukjlm0qhsr5bpa2fbe6s@4ax.com> <pprd4s$8s2$1@dont-email.me> <3b61ba6c-2db5-4080-9144-c080861a5432@googlegroups.com>

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"whit3rd" <whit3rd@gmail.com> wrote in message
news:3b61ba6c-2db5-4080-9144-c080861a5432@googlegroups.com...
>Metal
> should hold up well. If ZrO turns to Zr, though, it's gonna lose the
> smooth surface.

ZrO's binding energy is higher than that of Fe.

You might as well consider transmutation of Fe or Zr due to high energy
spallation, too, but you'll only be that much further down in the noise. Or
Wigner energy. Bulk effects are an extremely small priority. It would have
to be in orbit for a very long time indeed.

I don't know that asteroids have these problems after billions of years.
And common minerals, like olivine, aren't as stable as zirconia.

Photoemission is the only mechanism with a plausible risk factor -- showers
of charged particles exiting a surface, multiplied by the energy of the
impacting particle.

There should be ions in there, too, but again, that's a bulk effect manifest
at the surface. Sure, it'll roughen the surface, atomically. The surface
is already microscopically rough. Drops in the bucket.

I'd worry much more about chemical breakdown of the grease. If it's carbon
or silicone based, expect fragmentation and cross-linking. If it can be dry
(graphite, MoS2 or PTFE?), that helps, but a purely dry lubricant would only
stay in place by van der Waals forces.

Material composition is critical inside a fission reactor, say. But that's
not an environment that humans can sit in for years with mainly just an
elevated cancer risk. That's an environment that liquifies biological
tissue in -- minutes, hours, days?
http://www.srl.caltech.edu/ACE/ASC/DATA/bibliography/ICRC2005/usa-mewaldt-RA-abs1-sh35-oral.pdf
This says space is ~Sv/yr equivalent, which is kind of scary actually, to
the point that I wonder if long-duration astronauts are growing anything
interesting yet. But it's not something you're likely to die of, during a
mission.

And that's in the mSv for casual (days-long) missions, comparable to a PET
scan, or CT of the more sensitive areas, so as long as you don't make a
habit of, say, space tourism, it's not going to affect your long-term risk.

Tim

--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

Thread

various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-12 12:50 -0700
  Re: various OTs George Herold <gherold@teachspin.com> - 2018-10-12 13:04 -0700
    Re: various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-12 13:48 -0700
      Re: various OTs George Herold <gherold@teachspin.com> - 2018-10-12 17:46 -0700
  Re: various OTs dplatt@coop.radagast.org (Dave Platt) - 2018-10-12 14:53 -0700
    Re: various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-12 15:30 -0700
      Re: various OTs Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2018-10-13 10:13 +0100
        Re: various OTs John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-13 09:33 -0700
          Re: various OTs Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-13 14:15 -0400
          Re: various OTs Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2018-10-15 10:09 +0100
            Re: various OTs John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-15 06:50 -0700
    Re: various OTs Clive Arthur <cliveta@nowaytoday.co.uk> - 2018-10-13 10:37 +0100
      Re: various OTs DecadentLinuxUserNumeroUno@decadence.org - 2018-10-13 10:01 +0000
        Re: various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-13 11:08 -0700
      Re: various OTs John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-13 09:55 -0700
      Re: various OTs MikeP <mjp993@googlemail.com> - 2018-10-16 03:22 +0000
    Re: various OTs Robert Baer <robertbaer@localnet.com> - 2018-10-13 22:39 -0700
      Re: various OTs Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2018-10-14 21:43 +0200
        Re: various OTs Robert Baer <robertbaer@localnet.com> - 2018-10-15 19:46 -0700
  Re: various OTs DecadentLinuxUserNumeroUno@decadence.org - 2018-10-12 23:55 +0000
    Re: various OTs Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-10-12 16:58 -0700
    Re: various OTs bill.sloman@ieee.org - 2018-10-12 17:52 -0700
    Re: various OTs speff <spehro@gmail.com> - 2018-10-18 06:53 -0700
      Re: various OTs John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-18 06:59 -0700
        Re: various OTs tabbypurr@gmail.com - 2018-10-18 14:10 -0700
          Re: various OTs "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-10-18 17:49 -0500
        Re: various OTs Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-18 21:04 -0400
          Re: various OTs Steve Wilson <no@spam.com> - 2018-10-19 01:34 +0000
            Re: various OTs <698839253X6D445TD@nospam.org> - 2018-10-19 07:11 +0000
  Re: various OTs "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-10-12 19:10 -0500
    Re: various OTs Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-10-13 06:22 -0700
      Re: various OTs Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-13 14:16 -0400
        Re: various OTs John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-13 17:19 -0700
    Re: various OTs whit3rd <whit3rd@gmail.com> - 2018-10-13 12:24 -0700
      Re: various OTs Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-13 17:30 -0400
        Re: various OTs Jasen Betts <jasen@xnet.co.nz> - 2018-10-14 20:13 +0000
          Re: various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-14 13:59 -0700
            Re: various OTs Steve Wilson <no@spam.com> - 2018-10-14 23:58 +0000
              Re: various OTs Steve Wilson <no@spam.com> - 2018-10-15 01:05 +0000
                Re: various OTs Jasen Betts <jasen@xnet.co.nz> - 2018-10-15 05:57 +0000
                Re: various OTs DecadentLinuxUserNumeroUno@decadence.org - 2018-10-15 11:09 +0000
              Re: various OTs <698839253X6D445TD@nospam.org> - 2018-10-15 07:23 +0000
      Re: various OTs "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-10-13 21:39 -0500
  Re: various OTs bitrex <user@example.net> - 2018-10-13 00:08 -0400
  Re: various OTs <698839253X6D445TD@nospam.org> - 2018-10-13 06:59 +0000
    Re: various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-13 12:08 -0700
  Re: various OTs <698839253X6D445TD@nospam.org> - 2018-10-13 07:27 +0000
    Re: various OTs speff <spehro@gmail.com> - 2018-10-18 06:55 -0700
  Re: various OTs Winfield Hill <hill@rowland.harvard.edu> - 2018-10-13 07:32 -0700
    Re: various OTs John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-13 12:17 -0700
  Re: various OTs Joseph Gwinn <joegwinn@comcast.net> - 2018-10-15 08:37 -0400
    Re: various OTs Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2018-10-15 13:58 +0100
      Re: various OTs Tom Gardner <spamjunk@blueyonder.co.uk> - 2018-10-15 14:34 +0100
      Re: various OTs Clifford Heath <no.spam@please.net> - 2018-10-16 10:26 +1100
    Re: various OTs Clive Arthur <cliveta@nowaytoday.co.uk> - 2018-10-16 10:46 +0100
      Re: various OTs tabbypurr@gmail.com - 2018-10-16 08:46 -0700
        Re: various OTs Clive Arthur <cliveta@nowaytoday.co.uk> - 2018-10-16 19:53 +0100
          Re: various OTs tabbypurr@gmail.com - 2018-10-17 05:56 -0700

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