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http://arxiv.org/abs/1501.06981
复冰现象(1850):
冰受压融化但撤压后再结冰。所以载重的细线在-10度左右可以穿过但不能切断冰块。冰川底部受压融化而形成河流之源。
机理【1,4】:
1)冰的熔化温度正比与H-O键能。
2)由于氧-氧间的电子对的库伦排斥和氢键(O:H-O)两段作用势的非对称性,受压时O:H键被压缩而H-O键被挤长;被挤长的H-O键变弱能量降低,所以冰的熔点降低。
3)当O:H断裂时,氧原子总是寻求新的近邻以稳定它的sp3轨道杂化结构。所以氢键有超强的自修复功能。
Unlike other unusual materials whose bonds contractunder compression, the O:H nonbond undergoes contraction and the H-O bondelongation towards O:H and H-O length symmetry in water and ice. The energydrop of the H-O bond dictates the melting point Tm depression ofice. Once the pressure is relieved, the O:H-O bond fully recovers its initialstate, resulting in Regelation.
Ref:
【4】 Anomaly3: Regelation,http://arxiv.org/abs/1501.06981
【3】Anomaly2: Floating ice, http://arxiv.org/abs/1501.04171
【2】 Anomaly1: Mpemba effect, http://arxiv.org/abs/1501.00765
【1】 Hydrogen-bond relaxation dynamics: resolvingmysteries of water ice. Coord. Chem. Rev., 2015. 285:109-165.
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