[time-nuts] 1 kg standard (was:Re: Better quartz crystals with single isotope ?)
Richard (Rick) Karlquist
richard at karlquist.com
Sun Apr 22 16:48:28 EDT 2018
A neophyte question about this topic: Since we know that 0.001
cubic meter of water displaces 1 liter, and that it weighs 1 kg,
and meters are based on wavelengths of light, why
do we need a separate artifact of mass? Also, can we measure
the mass of the artifact in Paris based on water substitution?
Articles about this topic are always presented as if the answers
Don't they base 0 degree Celsius on the triple point of water?
What's wrong with that?
On 4/22/2018 10:20 AM, Bob kb8tq wrote:
>> On Apr 22, 2018, at 12:19 PM, Poul-Henning Kamp <phk at phk.freebsd.dk> wrote:
>> Silicon comes in a number of isotopes but 95% of it is Silicon-28.
>> When you make pure mono-crystaline silicon, you get 50-60% better
>> thermal conductivity if you only use Silicon-28 atoms.
>> Yes, you read that right: 50-60% improvement for removing the
>> remaining 5% other silicon isotopes, and for this and other reasons,
>> sorting silicon atoms by isotope is now a thing, which amongst other
>> side effects have made the Advogardo Project possible.
>> I can't help wonder if there may be similar interesting effects in
>> quartz crystals, if they were monoisotopic ?
>> Several relevant mechanisms can be imagined, lower internal damping,
>> higher stiffness etc. etc.
>> We know a LOT about quartz and have a very good theory for its
>> behaviours, but i find no signs anybody has ever touched monoisotopic
>> The obvious experiment is not rocket-science, nor does it demand
>> inordinate resources for amateurs, see for instance from 03:35:
>> But it is clearly beyond what I have time to persue.
>> Do we know anybody in the quartz business who needs a really cool
>> research project ?
> You could put it on the list with the 1 Kg quartz resonator proposal …..
> https://tf.nist.gov/general/pdf/2638.pdf <https://tf.nist.gov/general/pdf/2638.pdf>
> Also an offshoot of people thinking about the implications of all this as it relates to resonators.
>> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
>> phk at FreeBSD.ORG | TCP/IP since RFC 956
>> FreeBSD committer | BSD since 4.3-tahoe
>> Never attribute to malice what can adequately be explained by incompetence.
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
More information about the time-nuts