| DOI | Trouver le DOI : https://doi.org/10.1103/PhysRevB.86.054110 |
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| Auteur | Rechercher : Tulk, C.A.; Rechercher : Klug, D.D.1; Rechercher : Molaison, J.J.; Rechercher : Dos Santos, A.M.; Rechercher : Pradhan, N. |
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| Affiliation | - Conseil national de recherches du Canada. Institut Steacie des sciences moléculaires du CNRC
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| Format | Texte, Article |
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| Résumé | In a process similar to the formation of high-density amorphous ice, amorphous methane hydrate was formed by the pressure-induced collapse of crystalline methane clathrate at 32 kbar and 100 K. This produced a regular array of methane embedded within cavities in an amorphous water network. In situ annealing results in further densification into a more disordered and higher density amorphous state before crystallization into ice VIII and hexagonal clathrate. Whereas the very high-density amorphous form of pure water undergoes a glass transition near 130 K at low pressure and crystallizes over a broad pressure range at ∼160 K, the amorphous network of the water-methane binary system exhibits a region of metastability that persists up to 220 K between 15 and 40kbar. It appears that in this system the connectivity of the water network exhibits sufficiently low mobility so as to inhibit the diffusion and phase separation of the constituents until 220 K, where the high-pressure ice VIII crystallization can occur. The structure of the amorphous form is studied by neutron diffraction and the hydration of methane in this disordered water network is more closely related to the small clathrate cage than the large. ©2012 American Physical Society. |
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| Date de publication | 2012 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 21269261 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | 34bbba1f-1f61-4c2d-9432-4909084e2f5a |
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| Enregistrement créé | 2013-12-12 |
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| Enregistrement modifié | 2020-04-21 |
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