Effects of Al:Si and (Al + Na):Si ratios on the properties of the international simple glass, part II: Structure
Effects of Al:Si and (Al + Na):Si ratios on the properties of the international simple glass, part II: Structure
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Al:Si 和 (Al + Na):Si 比例对国际简单玻璃性能的影响，第二部分：结构
DOI：
10.1111/jace.17447
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发表时间：
2020
影响因子：
3.9
通讯作者：
J. Vienna
中科院分区：
文献类型：
--
作者：
Xiaonan Lu;J. Reiser;B. Parruzot;L. Deng;Igor M. Gussev;J. Neuefeind;T. Graham;Hongshen Liu;J. Ryan;Seong H. Kim;N. Washton;M. Lang;Jincheng Du;J. Vienna
含高氧化铝的高放射性废物（HLW）将在汉福德工厂的废物处理厂进行玻璃化处理。与先前研究的HLW玻璃相比，所得到的高氧化铝玻璃将具有不同的组成-结构-性质（C-S-P）关系。这些C-S-P关系决定了玻璃的加工性能和产品耐久性，因此必须加以理解。本研究的主要目的是了解详细的结构变化所造成的Al：Si和（Al + Na）：Si替代在一个简化的核废料模型玻璃（ISG，国际简单玻璃）相结合的实验结构表征和分子动力学（MD）模拟。这两个系列的玻璃的结构通过中子全散射和27 Al，23 Na，29 Si和11 B固态核磁共振（NMR）光谱进行了表征。此外，分子动力学模拟被用来生成硼硅酸盐玻璃的原子结构模型和模拟结果进行了验证的实验结构数据。系统地研究了硼硅酸盐玻璃的短程（例如，键距，配位数等）和中程（例如，氧形态，网络连接性，多面体键）结构特征作为取代度的函数。结果表明，除B-O对外，阳离子-氧对的键距和配位数对Al：Si和（Al + Na）：Si取代相对不敏感。此外，Al：Si取代导致三桥氧物种的增加，而（Al + Na）：Si取代产生非桥氧物种。发现Si-[NBO]（Na+）、[3]B-[NBO]（Na+）、[4]B（主要是Ca 2+）、[4]Al（几乎相等地分裂Na+和Ca 2+）和[6]Zr（主要是Ca 2+）的电荷补偿剂偏好。网络前体-BO-网络前体键的偏好也被制成表格;以较低的Si-O-[3]B和[3]B-O-[3]B键为代价，优选Si-O-Al和Al-O-Al。这些结果提供了关于性质变化的结构起源的见解，例如由取代引起的玻璃化转变温度，为未来改进理论和计算机模拟模型提供了基础。
High‐alumina containing high‐level waste (HLW) will be vitrified at the Waste Treatment Plant at the Hanford Site. The resulting glasses, high in alumina, will have distinct composition‐structure‐property (C‐S‐P) relationships compared to previously studied HLW glasses. These C‐S‐P relationships determine the processability and product durability of glasses and therefore must be understood. The main purpose of this study is to understand the detailed structural changes caused by Al:Si and (Al + Na):Si substitutions in a simplified nuclear waste model glass (ISG, international simple glass) by combining experimental structural characterizations and molecular dynamics (MD) simulations. The structures of these two series of glasses were characterized by neutron total scattering and27Al,23Na,29Si, and11B solid‐state nuclear magnetic resonance (NMR) spectroscopy. Additionally, MD simulations were used to generate atomistic structural models of the borosilicate glasses and simulation results were validated by the experimental structural data. Short‐range (eg, bond distance, coordination number, etc) and medium‐range (eg, oxygen speciation, network connectivity, polyhedral linkages) structural features of the borosilicate glasses were systematically investigated as a function of the degree of substitution. The results show that bond distance and coordination number of the cation‐oxygen pairs are relatively insensitive to Al:Si and (Al + Na):Si substitutions with the exception of the B‐O pair. Additionally, the Al:Si substitution results in an increase in tri‐bridging oxygen species, whereas (Al + Na):Si substitution creates nonbridging oxygen species. Charge compensator preferences were found for Si‐[NBO] (Na+),[3]B‐[NBO] (Na+),[4]B (mostly Ca2+),[4]Al (nearly equally split Na+and Ca2+), and[6]Zr (mostly Ca2+). The network former‐BO‐network former linkages preferences were also tabulated; Si‐O‐Al and Al‐O‐Al were preferred at the expense of lower Si‐O‐[3]B and[3]B‐O‐[3]B linkages. These results provide insights on the structural origins of property changes such as glass‐transition temperature caused by the substitutions, providing a basis for future improvements of theoretical and computer simulation models.
影响因子：
3.5
作者：
Bhaskar, Pratik;Kumar, Rajesh;Krishnan, N. M. Anoop
通讯作者：
Krishnan, N. M. Anoop