ELCIDATION OF MECHANISM OF ICE SEGREGATION BY Keisukea japonica Miq., Lamiaceae AIMING FOR BIOMIMETICS

为了弄清海带海带冰分离现象的机理，进行了各种室内试验。结果表明，木质部的成核温度可达-2.1~-2.5℃，木质部表面有1微米大小的凹坑，三维荧光图像分析表明，木质部中的水分通道存在于导管周围至木质部表面。根据这些发现，可以解释说，小坑起到了阻挡冰侵入木质部的作用，使土壤水分通过冰生长表面的过冷通过根部和木质部移动到木质部表面，并作为冰分离现象持续冻结。这些现象可应用于仿生微型水泵。这种简单的热驱动泵系统将是微机电一体化组件化技术的一个很好的工具。

In order to clarify the mechanism of ice segregation phenomenon by Keisukea japonica Miq., Laminaceae, various laboratory experiments were conducted. As a result, it was verified that the nucleation temperature reaches to -2.1 to -2.5 deg C, pits having 1 micrometer in size are on the xylem surface through the electron microscopic analysis, and the water pathway in the xylem exists in the periphery of vessel to the xylem surface through three-dimensional fluorescent image analysis. Based on these findings, it can be explained that small pits play a role as a barrier to interrupt the ice intrusion into the xylem, so that soil water moves to the xylem surface through roots and xylem by the super cooling of growing surface of ice and freezes continuously as ice segregation phenomenon. These phenomena can be applied for a biomimetic micro water pump. The simple pump system driven by thermal condition will be a good tool for a component technology in the micro mechatronics.