Re:1945-Uranium to Japan

[JPreisig@AOL.COM]

Hi Radsafers:



      From: jpreisig@aol.com   .



      I was trying to ignore all this, but the talk of Germany, Japan, 

Submarines

and Uranium was too much for me.  So, here goes.



      I don't think there was 550 kg of U-235 anywhere in the world in 1945, 

or

a few years earlier.  So, let's assume it was natural uranium.  The amount if

U-235 in this pile of Uranium, if extracted, would be roughly  4 kilograms.

(0.7 % U-235 in natural Uranium).    4 kilograms of U-235 is an interesting

number.  Enough for criticality??? --- I don't know.  I think Frisch and 

Peirels

original estimate for criticality was one kilogram or so; I guess their

calculation was in the form of a British Memorandum that wasn't published in

the open literature (lest Heisenberg would have known what actual U-235

critical mass was).???  Some German loading up this submarine with Uranium

had some idea what U-235 critical mass was.  And the Uranium was on

its way to Japan for U-235 extraction via their cyclotron???  Didn't the 

Japanese

have any Uranium Ore handy???   Hmmmmm....  Frisch and Peirels did their

work in the early 1940's???



      Enough of that.



      Dr. Nardi asked what the density and/or pressure (of Uranium) at the 

center of the Earth would be.  Some indication of such numbers can be

found in the text "Physics of the Earth" by Frank Stacey.  The information is

found in an appendix in this book;  my copy is old with a green cover.  The 

information does not specifically address Uranium.  Read the appendix

to understand what is actually being computed/modelled.  If one has a

petrologist (probably a metamorphic or igneous petrologist) handy, one could

ask him or her, what the phase diagram (as a function of temperature and

pressure) for Uranium looks like.



      It has been my impression that the heat emanating from the Earth is

due primaily to heat resulting from radionuclide decay.  To find out that 

this

heat is due to some Earthly reactor is news to me --- Frankly, I don't 

believe

it.



     Anyway, have a good day tomorrow and make your way through this

hot weather.  I'm glad we got through the 4th of July relatively unscathed.





                Regards,                       J.R. Preisig, Ph.D.





************************************************************************

You are currently subscribed to the Radsafe mailing list. To unsubscribe,

send an e-mail to Majordomo@list.vanderbilt.edu  Put the text "unsubscribe

radsafe" (no quote marks) in the body of the e-mail, with no subject line.

You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/