Liquid-liquid phase transition and dynamic properties of low-temperature water under pressure, and chemical-pressurization effects on water

低温水在压力下的液-液相变和动态特性以及化学加压对水的影响

• 批准号: 21340118
• 负责人: OGUNI Masaharu
• 金额: $ 12.65万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009 至 2011
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21340118/
• 关键词: 水; ガラス転移; 相転移; 熱容量; 構造緩和; 熱測定; エンタルピー緩和; 水素結合ネットワーク

Heat capacities of the dilute aqueous solutions, with different second components, confined within silica nanopores were measured by calorimetry. The heat capacity maximum, which appeared around 233 K in pure water, developed to a clear peak with doping hydroxylamine(HA) while it disappeared with doping methanol and so on. The peak revealed characters of first-order transitions, and the transition temperature increased with increase in the HA composition x and decreased with pressurization. Simultaneously the transition peak area in the thermal analysis of a 5 wt% HA solution decreased with pressurization. Based on these results, we proposed a new model of p-T-x phase diagram in which HA doping provides an effect of negative pressurization on water and a liquid-liquid phase transition line and a critical point as the line terminal exist in a negative pressure range.

通过量热法测量限制在二氧化硅纳米孔内的具有不同第二组分的稀水溶液的热容量。纯水中热容最大值出现在233 K左右，掺杂羟胺(HA)后出现清晰的峰，掺杂甲醇等后热容最大值消失。该峰揭示了一级转变的特征，转变温度随着HA组成x的增加而升高，并随着加压而降低。同时，5 wt% HA 溶液的热分析中的过渡峰面积随着加压而减小。基于这些结果，我们提出了一种新的 p-T-x 相图模型，其中 HA 掺杂提供了对水和液-液相变线的负压作用以及线末端存在于负压范围内的临界点。

项目成果

215 K Glass Transition and 233 K Heat-Capacity Hump of the Water within Pores of Silica MCM-41, and Their Deuteration Effects

二氧化硅 MCM-41 孔内水的 215 K 玻璃化转变和 233 K 热容驼峰及其氘化效应

• 发表时间: 2010
• 作者: M.Oguni;Y.Kanke;A.Nagoe
• 通讯作者: A.Nagoe

低温ナノ細孔水の相挙動への第2成分添加効果

第二组分添加对低温纳米孔隙水相行为的影响

• 发表时间: 2011
• 作者: M. Katsuragawa;Kanaka Raju P.;K. Shiraga;H. Aoki;F. Benabid;F. Couny;and Y. Y. Wang;名越篤史,小國正晴
• 通讯作者: 名越篤史,小國正晴

Findings of Cp Maximum at 233 K for the Water within Silica Nanopores and Very Weak Dependence of the Tmax on the Pore Size

• DOI: 10.1021/jp104970s
• 发表时间: 2010-11-11
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY B
• 影响因子: 3.3
• 作者: Nagoe, Atsushi;Kanke, Yasuhiro;Namba, Seitaro
• 通讯作者: Namba, Seitaro

メソポーラスシリカ細孔中の水の熱異常へのメタノール添加効果

添加甲醇对介孔二氧化硅孔隙中水热异常的影响

• 发表时间: 2010
• 作者: 名越篤史;小國正晴
• 通讯作者: 小國正晴

Glass-Transition Behaviors of the Dilute Aqueous Solutions Confined within Nano-Pores : Effect of the Development of Hydrogen-Bond Network

纳米孔内稀水溶液的玻璃化转变行为：氢键网络发展的影响

• 发表时间: 2010
• 作者: A.Nagoe;Y.Kanke;M.Oguni
• 通讯作者: M.Oguni