@article{oai:mie-u.repo.nii.ac.jp:00004711,
 author = {Sakka, Sumio and 作花, 済夫 and Kamiya, Kanichi and 神谷, 寛一 and Matusita, Kazumasa and 松下, 和正 and Okamura, Tsuneyoshi and 岡村, 常良},
 journal = {Research reports of the Faculty of Engineering, Mie University},
 month = {Dec},
 note = {application/pdf, The low temperature viscosity in the range of <special>10 7~10 11</special> poises was measured using the penetration viscometer for glasses of the series <special>xNa2O・(10-x)K2O・90B2O3, xNa2O・(20-x)K2O・80B2O3, xLi2O・(10-x)K2O・90B2O3, xLi2O・(20-x)K2O・80B2O3 and xNaKO・(100-x)B2O3</special> prepared by melting in vacuum. The temperature dependence of viscosty was expressed by the Arrhenius type equation. Generally, viscosity and activation energy for viscous flow of the glass melted in vacuum were higher than those of the glass melted in air. The most pronounced finding was absence of the "mixed alkali effect" in viscosity no marked minimum was observed on the curves relating log viscosity with the alkali ratio R/(R+R'), in contrast with the general belief based on the fact the log viscosity isotherms of <special>Na2O-K2O-SiO2</special> and other glasses showed a pronaunced minimum. In other words, the minimum would be present only in a limited number of systems. As to variation of viscosity with the total alkali content, it was found that viscosity of <special>xNaKO・(100-x)B2O3</special> glasses shows a maximum at 25 mol% alkali oxide in the same fashion as single alkali borate glasses. These results would imply that the structural interpretation of viscosity of mixed alkali glasses could be based on the structural concept developed for single alkali glasses.},
 pages = {47--58},
 title = {Viscosity of Mixed-Alkali Borate Glasses},
 volume = {1},
 year = {1976}
}