John M. Steele
Sat, 04 Sep 2010 04:40:55 -0700
I was also a bit confused on this, as well as thermodynamic temperature vs the ITS-90 practical temperature scale. The first link is from our friend Anthony O'Conner. I am aware many people have set him to "ignore," but the article is worth a read. The second is a follow-on link from the first on ITS-90. The two, taken together, clarified things a bit for me. http://www.nature.com/news/2009/170609/full/459902a.html http://www.nature.com/news/2009/170609/full/459902a/box/1.html
________________________________ From: "mech...@illinois.edu" <mech...@illinois.edu> To: U.S. Metric Association <usma@colostate.edu> Sent: Fri, September 3, 2010 12:04:56 AM Subject: [USMA:48460] Re: kelvin The triple point of water is the temperature at which the solid, liquid, and gas phases of isotopically natural water are in equilibrium. This temperature is the single fixed point of the "kelvin thermodynamic temperature scale"; defined numerically to be 273.16 kelvins. How can Boltzmann's constant be used to improve this scale? Where can we read the proposal for the 2011 CGPM meeting? ---- Original message ---- >Date: Thu, 2 Sep 2010 20:41:10 +0100 >From: "Martin Vlietstra" <vliets...@btinternet.com> >Subject: RE: [USMA:48457] Re: kelvin >To: <mech...@illinois.edu>, "'U.S. Metric Association'" <usma@colostate.edu> > >There is of course talk of a proposal to redefine the temperature scale at >the 2011 meeting of the CGPM by defining the value of Boltzmann's constant >and using that definition to derive the triple point of water etc.