I believe this is the SCIENCE magazine story on magnetism and the melting
temperature of ice. I found it here:

http://bric.postech.ac.kr/biotrend/science/science_view.php?nNum=94067


Harry

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Magnets Meddle With Melting
2004-12-13


In a strong magnetic field, ice melts at a higher temperature than normal, a
team of physicists has discovered. The effect is tiny--no household magnet
is going to stave off the thawing of your freezer contents in a power
failure - but is still a thousand times more than theory predicts.

With water, water everywhere, one might be forgiven for thinking that
scientists unraveled all its secrets long ago. But water "is a system full
of surprises," says Caltech physicist Kenneth Libbrecht. The latest of those
surprises comes from Hideaki Inaba and his colleagues at Chiba University in
Chiba, east of Tokyo, who studied the effect of strong magnetic fields on
the melting point of ice. Using a refined version of a technique called
differential scanning calorimetry, the team monitored the temperature
difference between the sample and a reference material as the pair were
slowly warmed. As the ice started to melt, it absorbed energy, giving rise
to a telltale temperature difference flagging the melting point.
In the presence of a strong 6 Tesla magnetic field--about four or five times
stronger than the magnetic field inside a standard hospital MRI scanner--the
team found that ice's melting point increased by 5.6 millikelvin, they
report in the 1 December issue of Applied Physics. This result was a
surprise: thermodynamic theory predicts a shift a thousand times smaller.
Inaba believes the answer may lie in the magnetic field's influence on the
vibration and rotation of water molecules, which he argues stabilizes the
ice and hikes the temperature needed to melt it.

"It looks like an interesting result, and is worth trying to understand,"
says Libbrecht. Inaba's work follows the recent discovery by Seiichiro
Nakabayashi and his colleagues at Saitama University in Japan that water's
ability to bend light is also influenced by powerful magnetic fields. The
two effects may well be related, speculates Inaba. Now the researchers need
to come up with a theory that explains them both, says Libbrecht. "Until you
have some theory to pin on it, you just put it on the
wild-and-interesting-phenomena shelf," he says.

--ANDREW WATSON

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