I am sure that this will not be
the last word. I remember as a lad clearing
a sheltered slab of what I like to refer to as biologically active water (fish
survived swimming in it) and clearly seeing the bottom of the pool a good three
feet down through over a foot of completely clear ice. The crystals surely began as long needles and
slowly interwove to form this unusual ice form.
Most ice is formed with short crystals and this provides a cloudy media.
I have found plenty of implied
questions with our common water and ice that appear when a slow cooling process
is applied. The work unfortunately takes
patience.
Glass like ice may turn out to
have some importance although certainly not where humans wish to function. At the temperatures used, metals also change
behavior and may not be trusted.
When Water Becomes Glass
by Staff Writers
Rapid cooling of ordinary water or compression of ordinary ice: either
of these can transform normal H2O into an exotic substance that resembles glass
in its transparency, brittleness, hardness, and luster.
Unlike everyday ice, which has a highly organized crystalline structure,
this glass-like material's molecules are arranged in a random, disorganized
way.
Scientists have studied glassy water for decades, but the exact
temperature at which water acquires glass-like properties has been the subject
of heated debate for years, due to the difficulty of manipulating pure glassy
water in laboratories.
Understanding the properties of water is important for astrobiologists
because the survival of life as
we know it depends on the presence of liquid water.
Now, in a paper published in the AIP's Journal of Chemical Physics,
physicists from the University of
Pisa and the Consiglio Nazionale delle Ricerche at the Institute for
Chemical-Physical Processes (CNR-IPCF) in Pisa, Italy, claim to have put an end
to the controversy.
Unlike previous attempts in which scientists tried to measure the
transition temperature directly, the CNR team "snuck up" on the
answer by inferring the temperature from a thorough study of the dynamics of
water. They examined water's behavior in bulk and at the nano-scale, at high
temperatures and low, combining their own experimental results with 15
decades' worth of research by colleagues.
They also measured the glass transition temperature and the molecular
behavior of water that had been doped with other materials, and used this
information to set lower and upper boundaries on the transition temperature for
pure water. Taken together, their evidence points to a magic number of
approximately 136 Kelvin (-137 Celsius).
The authors say their work supports traditional views of this
phenomenon and refutes recent claims that the transition is above 160 Kelvin
(-113 Celsius).
The research could find uses in technology associated with food science
and the cryopreservation of biological materials, as well as in the study of
water in comets and on the surface of
planets.
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