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Measuring the Densities of Aqueous Glasses at Cryogenic Temperatures
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从体积测量中了解相当大的玻璃原材料的特性
Marzena Rams-Baron1, Alfred Błażytko1, Riccardo Casalini2
1August Chełkowski Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland.
The Journal of chemical physics
|August 9, 2024
概括
在相当大的玻璃制造器中,玻璃过渡的动态均由热能和自由体积波动控制. 高压灵敏度并不一定意味着体积显著影响玻璃过渡动态.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 大型玻璃成型器具有独特的特性和应用,但其玻璃过渡动态仍然不完全理解.
- 之前的介电学研究表明,超冷动力学对压缩非常敏感.
研究的目的:
- 为了研究控制大分子玻璃过渡动态的因素.
- 分析热能,自由体积和压力对分子重定向的影响之间的相互作用.
主要方法:
- 分析结构放松时间作为温度和压力的函数.
- 从压力-体积-温度 (PVT) 测量中确定状态的方程.
主要成果:
- 与直觉相反,发现热能和自由体积波动在控制重定向动态方面几乎同样重要.
- 缩放指数 γ = 3.0 和 Ev/Ep 比率为 0.6 表示放松动态受热和体积效应的影响.
- 高激活体积 (ΔV) 和dTg/dP值不仅预测了体积对玻璃过渡动态的显著贡献.
结论:
- 在相当大的玻璃形成器中,玻璃过渡的动态是由热波动和自由体积之间的平衡所支配的.
- 玻璃过渡温度对压力的灵敏度 (dTg/dP) 并不是体积在放松动态中的主导作用的明确指标.
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