在氧化-氧化融中检测一级液态/液态相变
G N Greaves1, M C Wilding, S Fearn
1Centre for Advanced Functional Materials and Devices, Institute of Mathematics and Physics, Aberystwyth University, Aberystwyth SY23 3BZ, UK. gng@aber.ac.uk
概括
酸融化物在高温下表现出可逆的第一阶段过渡,由纳米级液体分离和原子级结构变化证明. 这种现象在超冷液体中产生"多态旋转器".
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:
- 液体材料中的相变对于理解它们的特性至关重要.
- 之前的研究推断了来自灭玻璃的伊特里亚-溶液中的过渡.
- 在无接触条件下对高温液态相变的实地研究具有挑战性.
研究的目的:
- 在高温下研究伊特里亚-溶液中的现场相变.
- 在这些过渡过程中描述纳米和原子尺度的变化.
- 量化与观察到的转变相关的热力学特性.
主要方法:
- 结合的小角度X射线散射 (SAXS) 和广角X射线散射 (WAXS).
- 利用空气动力学悬浮在高温下无接触处理样品.
- 在现场观察到悬浮的结构演变和动态行为.
主要成果:
- 在高温下溶解的伊特里亚-中发现了一种第一阶段过渡.
- 萨克斯发现纳米级液体不混合,以可逆最大值表示.
- WAXS 显示了多面体包装的急剧变化,这意味着原子级结构变化.
- 观察到一个观察到的
- 多形态旋转器的多形态旋转器
- 一个由重复的转换驱动的现象.
结论:
- 酸融的高温过渡涉及纳米级液体脱离和原子级结构重组.
- 观察到的多形旋转器允许估计摩尔体积和的可逆变化.
- 这项研究为在极端条件下氧化物化的复杂行为提供了新的见解.
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