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Updated: Aug 12, 2025

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A Microfluidic Approach for the Study of Ice and Clathrate Hydrate Crystallization
Published on: August 18, 2022
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Hielo amorfo de densidad media
Alexander Rosu-Finsen1, Michael B Davies2,3, Alfred Amon1
1Department of Chemistry, University College London, London WC1H 0AJ, UK.
Resumen
Los investigadores descubrieron una nueva forma de hielo amorfo, el hielo amorfo de densidad media (MDA), a través de la molienda de bolas. Este hallazgo desafía la brecha de densidad establecida en el agua
Área de la Ciencia:
- Ciencias de los materiales
- Cosmología
- La geofísica
Sus antecedentes:
- Los hielos amorfos juegan un papel en los procesos cosmológicos y explican las anomalías del agua líquida.
- La comprensión actual del agua se basa en una brecha de densidad entre el hielo amorfo de baja densidad y de alta densidad.
Objetivo del estudio:
- Investigar la existencia y las propiedades de las estructuras de hielo amorfo.
- Desafiar el modelo de densidad establecida para el agua amorfa.
Principales métodos:
- Moldeo en bolas de hielo ordinario I a bajas temperaturas.
- Análisis estructural del hielo amorfo resultante.
- Compresión del hielo amorfo de densidad media (MDA) sintetizado.
Principales resultados:
- Descubrimiento de un hielo amorfo de densidad media (MDA) estructuralmente distinto dentro de la brecha de densidad previamente conocida.
- MDA puede representar el verdadero estado vidrioso del agua líquida o un estado cristalino cortado.
- La compresión de MDA aumenta significativamente su entalpía de recristalización.
Conclusiones:
- La existencia de MDA desafía el modelo tradicional de dos estados de agua amorfa.
- MDA podría ser el estado amorfo genuino del agua, impactando nuestra comprensión de sus anomalías.
- El agua, en sus formas amorfas, puede funcionar como un material geofísico de alta energía.
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