Mixing by microorganisms

微生物混合

• 批准号: 1109315
• 负责人: Jean-Luc Thiffeault
• 金额: $ 22万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1109315&HistoricalAwards=false
• 关键词: Mixing; microorganisms

This project will investigate the impact of swimming microorganisms on mixing. As a typical phenomenon, small organisms in the ocean called copepods let themselves slowly sink while agitating the fluid around them. Copepods form massive colonies and their collective motion helps bringing up nutrients, which are crucial to the organisms' reproduction, from deeper layers of the ocean. The stirring of a fluid by such swimming creatures is called biomixing. We will investigate biomixing from a variety of directions: we will model specific microorganisms, and use novel mathematical techniques to quantify their impact on fluid mixing. We will also compare the motion of these organisms as they sink to the dynamics of sedimenting particles, to see which aspects of the accumulated knowledge on sedimenting particles carry over to microorganisms, and which new features are introduced.It is well known that mixing is greatly enhanced by fluid motion--even the simple task of heating a house would be almost impossible without air convection. Biomixing has a wide range of possible applications, beyond immediate relevance to the fluid dynamics of microswimmers. An understanding of the impact of swimming microorganisms on mixing will help understanding phenomena such as oil breakup by bacteria, which is crucial in the aftermath of oil spills, or the life cycle of large colonies of organisms. The well-being of these colonies has a profound impact on climate change, since they absorb vast amounts of greenhouse gases. In addition, there are potential applications to microfluidics, where stirring by microorganisms can assist mixing at small scales. The inclusion of graduate students into this research, and their interdisciplinary training are an integral part of this project.

该项目将研究游泳微生物对混合的影响。 作为一种典型的现象，海洋中的小生物称为Copepods，让自己缓慢下沉，同时搅动周围的液体。 Copepods形成了巨大的菌落，它们的集体运动有助于提出营养，这对生物体的繁殖至关重要，从更深的海洋层中。 通过这种游泳生物搅拌液体称为生物粘合。我们将从各个方向研究生物综合：我们将建模特定的微生物，并使用新颖的数学技术来量化其对流体混合的影响。 我们还将比较这些生物在沉积颗粒的动力学时的运动，以查看在沉积颗粒上积累的知识的哪些方面将其延伸到微生物中，并引入了哪些新特征。众所周知，混合会通过流体运动来大大增强 - 在没有空气的情况下供暖的简单任务是不可能的。 生物综合具有广泛的可能应用，与微晶状体的流体动力学不直接相关。 对游泳微生物对混合的影响的理解将有助于理解现象，例如细菌分解的现象，这对于漏油的后果或大生物体菌落的生命周期至关重要。 这些殖民地的福祉对气候变化产生了深远的影响，因为它们吸收了大量的温室气体。此外，在微流体中也有潜在的应用，其中微生物搅拌可以在小尺度上有助于混合。将研究生纳入这项研究，他们的跨学科培训是该项目不可或缺的一部分。