caa a22 4500 467923515 CHVBK 20180406152923.0 cr unu---uuuuu 170328e20061001xx s 000 0 eng 10.1134/S1087659606050026 doi (NATIONALLICENCE)springer-10.1134/S1087659606050026 Kuryaeva R. Institute of Mineralogy and Petrography, Siberian Division, Russian Academy of Sciences, pr. Akademika Koptyuga 3, 630090, Novosibirsk, Russia aut Degree of polymerization of the CaAl2Si2O8 aluminosilicate glass [Elektronische Daten] [R. Kuryaeva] The pressure dependence of the refractive index for a glass of the composition 0.50SiO2 · 0.25Al2O3 · 0.25CaO at pressures up to 5.0 GPa is determined using a polarizing interference microscope and an apparatus with diamond anvils. The densities and compressibilities of the glass are calculated from the measured refractive indices within the framework of the theory of photoelasticity. The results are compared with the data obtained earlier for vitreous silica. The lower compressibility of the glass under investigation as compared to the compressibility of fused silica is in agreement with the degree of polymerization that is calculated with due regard for the formation of triclusters from the relationship NBO/T = (2O + 3O t − 4T)/T, where NBO (nonbridging oxygen) is the number of nonbridging oxygen atoms; O is the number of gram-ions of oxygen, except for of tricluster oxygen; O t is the number of gram-ions of tricluster oxygen; and T is the total number of gram-ions of network formers. Pleiades Publishing, Inc., 2006 Glass Physics and Chemistry Nauka/Interperiodica 32/5(2006-10-01), 505-510 1087-6596 32:5<505 2006 32 10720 https://doi.org/10.1134/S1087659606050026 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1134/S1087659606050026 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Kuryaeva R. Institute of Mineralogy and Petrography, Siberian Division, Russian Academy of Sciences, pr. Akademika Koptyuga 3, 630090, Novosibirsk, Russia aut NATIONALLICENCE 773 0- Glass Physics and Chemistry Nauka/Interperiodica 32/5(2006-10-01), 505-510 1087-6596 32:5<505 2006 32 10720 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer