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Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
当地WO4在负热膨胀ZrW2O8中排序的真实空间分布
Yukio Sato1, Yasuhisa Yamamura, Kazuya Saito
1Institute of Engineering Innovation, The University of Tokyo, 2-11-16 Yayoi, Bunkyo, Tokyo 113-8656, Japan. y_sato@sigma.t.u-tokyo.ac.jp
Journal of the American Chemical Society
|August 18, 2012
概括
硫酸呈现出异常的负热膨胀 (NTE). 新的电子显微镜揭示了纳米级WO(4) 障碍是这种现象的关键,为其独特的特性提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 固体通常在加热时膨胀,但也有例外.
- tungstate (ZrW(2) O(8)) 是一个显著的材料,在广泛的温度范围内表现出显著的负热膨胀 (NTE).
- 以前的研究强调了金属氧多面体在NTE机制中的作用,但缺乏微观细节.
研究的目的:
- 通过先进的电子显微镜研究ZrW(2) O(8) 中的WO(4) 四面体的局部排序.
- 了解ZrW(2)O(8) 中负热膨胀的微观起源.
- 根据实体空间观测,开发一个ZrW(2) O(8) 的微结构模型.
主要方法:
- 高分辨率电子显微镜的观测结果.
- 现实空间成像局部WO(4) 四面体分布.
- 分析纳米级的秩序和混乱现象.
主要成果:
- 这项研究提供了第一次直接观察到局部WO(4) 四面体在ZrW(2) O(8) 中的排序.
- 关键的发现包括部分逆转的WO(4) 排序和WO(4) 的纳米尺度破坏.
- 观察到兴奋剂可以增强WO(4) 障碍的程度.
结论:
- 观察到的纳米级WO(4) 障碍对于理解ZrW(2) O(8) 的负热膨胀行为至关重要.
- 为ZrW(2) O(8) 提出了一个新的微结构模型,为其局部结构提供了精细的视角.
- 这些发现对于理解局部结构在相变中的作用以及设计具有量身定制的热膨胀特性的材料至关重要.
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