Thermal, acoustic, and nuclear magnetic resonance studies of cesium borate glasses
Thermal, acoustic, and nuclear magnetic resonance studies of cesium borate glasses
复制标题
硼酸铯玻璃的热、声和核磁共振研究
DOI：
10.1016/s0022-3093(01)00754-2
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发表时间：
2001
影响因子：
3.5
通讯作者：
S. Kroeker
中科院分区：
文献类型：
--
作者：
Jessica R. Berryman;S. Feller;M. Affatigato;M. Kodama;Ben Meyer;Steve W. Martin;F. Borsa;S. Kroeker
本研究的目的是比较硼酸铯玻璃的物理性质和结构。硼酸铯玻璃可以表示为RCs2O·B2O3，其中R是氧化铯与氧化硼的摩尔比。我们报告了这些 0.0⩽R⩽0.55 硼酸铯玻璃的玻璃化转变温度 (Tg) 的详细研究。最初，Tgin 随着 R 的上升而单调增加。然后在 R=0.35 处趋于平稳，并在 R=0.425 处下跌。使用差示扫描量热计 (DSC) 获得的 Tg 数据与 Kodama 等人的差热分析仪 (DTA) 的 Tg 结果以及 Chryssikos 的每硼桥接氧数 (Z) 模型非常一致。我们使用 11B NMR 测定了相同硼酸铯玻璃样品的四面体配位 N4 中硼原子的分数。 N4 分数遵循与 Tgre 结果类似的曲线，直到 R=0.45，其中它随着 Tgfell 继续上升。此外，N4 数据也有类似的趋势，但始终高于使用 Kodama 和 Kojima 的超声波速度数据的模型计算出的数据。最后，与硼酸锂玻璃相比，NMR 数据并未显示硼酸铯中的 N4 分数显着降低。
The purpose of this study was to compare the physical properties and structure of cesium borate glasses. Cesium borate glasses can be denoted as RCs2O·B2O3, where R is the molar ratio of cesium oxide to boron oxide. We report a detailed study of the glass transition temperature (Tg) of these cesium borate glasses with 0.0⩽R⩽0.55. Initially, the Tgincreased monotonically as R rose. It then leveled out at R=0.35 and fell at R=0.425. The Tgdata obtained using a differential scanning calorimeter (DSC) are in good agreement with Kodama et al.'s Tgresults from a differential thermal analyzer (DTA) as well as Chryssikos' model of the number of bridging oxygens per boron (Z). We determined the fraction of boron atoms in tetrahedral co-ordination, N4, for the same cesium borate glass samples using11B NMR. The N4fractions followed a curve similar to that of the Tgresults until R=0.45, where it continued to rise as the Tgfell. Also, the N4data have a similar trend but are consistently higher than those calculated from a model which employed Kodama and Kojima's ultrasonic velocity data. Finally, the NMR data do not display a significant lowering of the N4fraction in cesium borate when compared to lithium borate glasses.