澄清了水的玻璃过渡行为,与过度灭的无机玻璃相比
Yuanzheng Yue1, C Austen Angell
1Section of Chemistry, Department of Life Sciences, Aalborg University, DK-9000 Aalborg, Denmark.
Nature
|February 20, 2004
概括
水水水水水,这是一个很好的方法.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 热力学是一种热力学.
背景情况:
- 对于具有广泛液体范围或快速冷却的液体来说,形成玻璃是常见的.
- 物质在重新加热时表现出不同的行为:好的玻璃制造者过渡到超冷的液体,而其他物质则结晶.
- 几十年来,人们一直在讨论水的玻璃过渡,在136 K.有一个被广泛接受但异常的过渡.
研究的目的:
- 为了研究在重新加热过程中过度灭的无机玻璃的行为.
- 将无机玻璃的热性能与玻璃水的热性能进行比较.
- 重新评估水的玻璃过渡的性质和存在.
主要方法:
- 过度灭无机玻璃的详细热量测量特性.
- 在无机玻璃上进行加热实验,观察结晶前的过渡.
- 无机玻璃和玻璃水之间的热数据的比较分析.
主要成果:
- 过度灭的无机玻璃在达到其玻璃过渡温度之前不会结晶.
- 在玻璃水中观察到的热效应类似于真正玻璃过渡的"阴影".
- 在水中被广泛接受的136K过渡不是主要的玻璃过渡.
结论:
- 在典型条件下,水的直接玻璃过渡不能通过实验进行探测.
- 对于水来说,真正的玻璃过渡可能发生在更高的温度下,被结晶掩盖.
- 水的136K过渡的异常行为被解释为它是一个次要效应.
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