Ultrasonic dehumidifier

Does anyone know about ultrasonic dehumidifiers? They are used in
the Biblioteca Centrale della Regione Siciliana, Palermo, Italy.
They are applied directly on the walls and need just a power supply.
It was said they prevent humidity rising from the walls. I don't
have any more information from the maintenance people. Thank you
for any information,

Marco Di Bella
Book conservator
Palermo
Italy


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                  Conservation DistList Instance 17:17
                  Distributed: Thursday, July 31, 2003
                       Message Id: cdl-17-17-011
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