The physical properties of small gas bubbles in soft elastic materials: theory and applications

软弹性材料中小气泡的物理性质：理论与应用

• 批准号: 6831-2011
• 负责人: Goldman, Saul
• 金额: $ 2.55万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=568491
• 关键词: physical; properties; small; gas; bubbles

Soft elastic materials have a degree of rigidity, and consequently a degree of intrinsic shape. They have fundamentally different properties from ordinary liquids such as liquid water, which have no rigidity or intrinsic shape (liquids are said to "take the shape of their container"). Examples of such soft materials include magma, soft rubber, "Jello", and soft tissues in the body. Unlike ordinary liquids, soft elastic materials can partially stabilize small gas bubbles suspended in them, giving the bubbles a longer lifetime than they would otherwise have. Simple liquids stabilize only large bubbles, in order to minimize surface tension effects. The tendency of soft elastic materials to partially stabilize small gas bubbles is relevant to the problem of Decompression Sickness (DCS) that can occur in scuba diving, aviation, and space exploration. The subject of elasticity has been studied in engineering for well over a century, mainly because of its relevance to the strength of materials. However the physical chemistry of elastic materials is not at all well characterized and is poorly understood. The grantee has recently begun a series of fundamental studies on the physical chemistry of soft elastic materials, particularly when these materials contain embedded gas bubbles. The point to these studies is to understand the behavior of such systems from a fundamental perspective. An important application will be to the problem of DCS in scuba diving. The connection this has to elasticity is that soft tissues in the body can be approximated as soft elastic materials, and DCS is believed to occur when gas bubbles in soft tissues in the body expand. Defense R&D Canada is a major player in the search for a biomarker for DCS (which is analogous to the search for biomarkers for cancer, heart disease, etc). This biomarker work however requires, as one of its inputs, accurate modeling and prediction of decompression stress. The applicant, whose earlier work included the creation of improved biophysical models for predicting decompression stress, and the role of elasticity in DCS, has begun collaborating with Defense R&D Canada on this problem.

软弹性材料具有一定程度的刚度，因此具有一定程度的内在形状。它们具有与普通液体（例如液体水）的根本不同的特性，这些液体没有刚性或固有形状（液体据说“采用其容器的形状”）。这种软材料的例子包括岩浆，软橡胶，“果冻”和体内软组织。与普通的液体不同，软弹性材料可以部分稳定悬浮在其中的小气泡，从而使气泡的寿命更长。简单的液体仅稳定大气泡，以最大程度地减少表面张力的影响。软弹性材料部分稳定小气泡的趋势与潜水，航空和空间探索中可能发生的减压疾病（DC）有关。 一个多世纪以来，已经在工程学中研究了弹性的主题，这主要是因为它与材料的强度有关。然而，弹性材料的物理化学性质根本没有很好地表征，也没有理解。受赠人最近开始了一系列关于软弹性材料物理化学的基本研究，尤其是当这些材料含有嵌入式气泡时。这些研究的目的是从基本的角度理解此类系统的行为。 一个重要的应用是在潜水中DC的问题。与弹性的联系是，体内的软组织可以近似为软弹性材料，并且当体内软组织中的气泡膨胀时，就会发生DCS。加拿大国防研发是寻找DC的生物标志物的主要参与者（类似于寻找癌症，心脏病等的生物标志物）。然而，这项生物标志物的工作需要作为其投入之一，对减压应力的准确建模和预测。申请人较早的工作包括创建改进的预测减压压力的生物物理模型，以及弹性在DC中的作用，已经开始与加拿大国防研发的合作。