X-Message-Number: 18924
Date: Sun, 14 Apr 2002 12:32:45 -0400
From: "Henry R. Hirsch" <>
Subject: Volume heating and cooling: Adiabatic demagnetization and

In cryonics, the problem with most heating and cooling techniques is that 
the energy has to be transmitted to or from a relatively large volume of 
tissue through a relatively small surface area. The rate of heating or 
cooling is therefore relatively slow. Microwave heating gets around this 
problem because the heat is produced throughout the tisssue volume. 
Adiabatic demagnetization with appropriate magnetic fluids can, in 
principle, offer the same advantage with respect to cooling. The 
tissue  would be perfused with a magnetized fluid. Upon demagnetization it 
would cool due to entropic effects. This is essentially the way liquid 
helium is brought to temperatures near absolute zero.

If I were young enough, strong enough, and rich enough, I would follow up 
on this idea myself. Since none of these apply, I offer the idea to the 
cryonics community at large. I have a lot of references that would be 
useful. If you want them, send me an e-mail. I won't reply right away 
because I am home recovering from surgery. However, when I can get back to 
my office, I'll send them along. Please provide a postal address and phone 
number as well as an e-mail address.

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