在玻璃d-曼尼托尔中通过纳米热量测量进行度放松的特征
Zijian Wang1, John H Perepezko1
1Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
The journal of physical chemistry. B
|February 18, 2025
概括
这项研究使用先进的纳米热量计来探索d-曼尼托玻璃中的度放松. 研究结果揭示了复杂的放松动态和玻璃材料中的潜在记忆效应,为多态性提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 玻璃科学 玻璃科学
背景情况:
- 眼镜中的多形态是一种复杂的现象.
- d-Mannitol 作为一种有价值的模型系统,用于研究玻璃状状态.
- 了解度放松对于描述玻璃行为至关重要.
研究的目的:
- 研究d-曼尼托尔玻璃中的度放松特性.
- 确定关键参数,如玻璃形成能力和液体脆弱性.
- 在各种热史下分析放松的动力学和机制.
主要方法:
- 高速,高精度的纳米热量测量.
- 控制冷却和加热速度的实验.
- 在延长的时间尺度上同热物理衰老.
- 基辛格分析和绝对反应速率理论.
主要成果:
- 确定了关键参数 (玻璃过渡温度,虚拟温度,结晶度).
- 用拉伸的指数函数分析了恩萨尔皮放松动力学.
- 观察到从β (β) 放松过渡到α (α) 放松.
- 没有增加激活的记忆效应的证据被发现.
结论:
- d-曼尼托尔表现出与多重形态相关的复杂放松行为.
- 这项研究提供了关于眼镜中度放松的动力学和机制的见解.
- 这些发现有助于更深入地了解玻璃材料动力学和记忆效应.
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