Exploring deeply supercooled liquid droplets in a vacuum

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18604
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 13:Condensed matter physics and related fields
• Research Institution: Kyushu University
• Principal Investigator: TERASAKI Akira 九州大学, 理学研究院, 教授 (60222147)
• Co-Investigator(Kenkyū-buntansha): 秋山 良 九州大学, 理学研究院, 准教授 (60363347) ; 堀尾 琢哉 九州大学, 理学研究院, 准教授 (40443022) ; 荒川 雅 九州大学, 理学研究院, 助教 (10610264)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 過冷却液体 / 液滴 / 真空 / 蒸発冷却 / 相転移

Outline of Final Research Achievements

We have explored deeply supercooled liquids of water and its dilute polyol solution by means of experiments based on liquid droplets in a vacuum along with theoretical approaches by molecular-dynamics simulation. Several properties of supercooled water were elucidated, including surface tension, viscosity, evaporation rates, homogeneous ice nucleation rates. Effects of polyol addition to the water were analyzed by focusing on delay in the freezing time as well as change in the hydration state. These achievements are expected to contribute to future development of science of matters in extreme environments.

Free Research Field

物理化学

Academic Significance and Societal Importance of the Research Achievements

過冷却液体の研究は、極限環境を扱う実験上の困難で停滞していたが、真空中の液滴を自在に発生・操作・制御する独自の実験技術を駆使し、純水および水溶液系の過冷却深部における物性解明を進めた点で、学術的意義が高い。研究協力者の学生が表彰されるなど、全国規模の学会で研究成果が高い評価を得たことも特筆に値する。さらに、成果の波及は物質科学に止まらず、特に水の謎の解明は生命科学にまで波及する点、また博士号取得者の輩出など若手研究者の育成の面でも成果を上げた点で、社会的意義も大きい。