Development of Oxygen Supply and Recovery System for Closed Environment in a Space -Approach to Low Power Consumption at Cultivating-

作为开发利用蓝藻（螺旋藻）光合作用供氧系统的基础研究，探讨了在微重力条件下利用低离心力形成螺旋藻养殖场的降能可能性。在地面和微重力条件下，在容器侧壁附近观察到气泡现象。在2000年的结果中，发现材料表面的评价、滑移面的形成以及气泡大小和频率的控制是最重要的。地面实验：采用液滴法测量接触角。在这项工作中，我们测试了接触角是由气泡测量的。我们用这个测量值来评估各种表面的特性。我们准备了比聚四氟乙烯更好的新表面。地面实验：我们在北海道国家工业研究所通过微重力实验建立了气泡大小和频率的控制程序。我们观察了由日本微重力中心制造的微重力条件下容器侧壁附近的气泡行为。研究发现，气泡行为分为三种模式。(1)空气分散在水中，气泡在侧壁上不接触。(2)空气在水中不分散，侧壁上有大气泡接触。(3)空气在水中不分散，在侧壁形成空气层。每个图案对应于接触角的值。由于我们通过实验证实了模式(3)，因此我们的方法证明了功率降低的可能性。

As a basic research for developing an Oxygen Supply system used photosynthesis of blue-green algae, Spirulina platensis, we investigated the possibility of power decreasing formed Spirulina Cultivated field, which used low centrifugal force, under microgravity. We observed a bubble behavior near the sidewall of vessel on the ground and under microgravity. In the results at 2000, it was found that the evaluation of a material surface, formation of slipping surface and the controlling of a bubble size and its frequency were the most important.Experiments on the ground :Contact angle was measured by liquid drop. In this work, we tested that contact angle was measured by bubble. We evaluated the characteristic of the various surfaces using this measurement value. We prepared the new surface that was more excellent than Teflon.Experiments on the ground :We established a controlling procedure of bubble size and its frequency by microgravity experiments at Hokkaido National Industrial Research Institute. We observed the bubble behavior near the sidewall of vessel under microgravity, which was created by Japan Microgravity Center. It was found that bubble behaviors were divided three patterns.(1) Air disperses in water and bubble does not contact on the sidewall.(2) Air does not disperse in water and large bubble contact on the sidewall.(3) Air does not disperse in Water and air layer forms on the sidewall.Each pattern corresponded to the value of the contact angle. Because we experimentally confirmed pattern (3), the possibility of power decreasing was proved by our procedure.