STRUCTURAL STUDY OF WATER CONFINED IN POROUS-GLASS BY NEUTRON-SCATTERING
STRUCTURAL STUDY OF WATER CONFINED IN POROUS-GLASS BY NEUTRON-SCATTERING
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DOI：
10.1063/1.465031
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发表时间：
1993-03-01
影响因子：
4.4
通讯作者：
BOSIO, L
中科院分区：
文献类型：
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作者：
BELLISSENTFUNEL, MC;LAL, J;BOSIO, L
为了研究水在界面处的结构性质，我们进行了Vycor玻璃连通孔内水的中子散射实验。承压水的结构因子和相应的径向分布函数被确定为温度的函数，从35摄氏度到-100摄氏度，以及玻璃的两种水化水平(完全水化和部分水化)。在27摄氏度时，承压水的结构因子与散体水的结构因子非常相似。当降低温度时，我们证明了在Vycor的气孔内过冷水是可能的，但不会达到如此小的限制空间所期望的程度。事实上，大的亲水二氧化硅界面的存在增强了冰的成核作用。观察到的冰相是立方冰，在完全水化的维科尔中，它出现在零下18摄氏度左右。另一个有趣的观察是，与完全水合的样品相比，部分水合的维科样品中的水过冷程度更高。此外，还发现了低至-40摄氏度的少量液态水的存在。
In order to study the structural properties of water at interfaces, we performed neutron scattering experiments of water confined inside interconnected pores of Vycor glass. The structure factors and the corresponding radial distribution functions of the confined water have been determined as a function of temperature from 35-degrees-C down to -100-degrees-C and for two levels of hydration of the glass (full and partial hydration). At 27-degrees-C, the structure factor of confined water is very similar to that of bulk water. When decreasing the temperature, we show that it is possible to supercool water inside pores of Vycor but not to the extent expected for such a small confining space. In fact the presence of large hydrophilic silica interface enhances the nucleation of ice. The observed phase of ice is the cubic ice which appears at about -18-degrees-C in the full hydrated Vycor. The other interesting observation is a greater degree of supercooling of water in partially hydrated samples of Vycor compared to fully hydrated ones. Moreover, the presence of a small amount of liquid water down to -40-degrees-C is identified.