分子爬行诱导疲劳 纤维素凝块的破裂 凝块
Dani Liu1, Zichang Jia2, Binchao Liu3
1Institute of Solid Mechanics, School of Aeronautic Science and Engineering, Beihang University, Beijing, 100191, China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|August 8, 2025
概括
纤维素网络在血液流动下疲劳,导致危险的血块. 循环负荷会导致分子变化,削弱纤维素并促进破裂,这对于了解中风和栓塞风险至关重要.
科学领域:
- 生物物理学的生物物理.
- 生物材料科学 生物材料科学
- 翻译医学是一种翻译医学.
背景情况:
- 纤维素网络构成了血栓 (血栓) 的结构基础.
- 脉动性血流可以导致纤维素网络的疲劳衰竭,导致脉栓事件,如中风和肺栓塞.
- 纤维素网络的疲劳机制对于血栓栓塞至关重要,与单调骨折行为相比,仍未得到充分研究.
研究的目的:
- 为了研究循环负荷下纤维素网络的疲劳机制.
- 了解纤维素中的纳米级分子变化如何导致宏观血栓破裂.
- 开发一个多尺度模型,将纤维素的分子力学与其疲劳行为联系起来.
主要方法:
- 在凝聚纤维素网络上的多尺度实验.
- 在循环负荷下模拟纤维素网络力学.
- 量化分析将纳米尺度的转变与宏观尺度的疲劳联系起来.
主要成果:
- 纤维素网络表现出一个矛盾的低疲劳值,尽管高断裂能量.
- 循环负荷会在纤维素分子链中诱导不可逆转的α-to-β转换.
- 这些转变导致分子爬行,能量消散,以及通过纤维破裂的裂传播.
- 一个多尺度连续模型量化地将纳米级机械与宏观尺度疲劳相关联.
结论:
- 血栓破裂可以被视为一个由循环压力下的累积形状损伤驱动的分子疾病.
- 这些发现挑战了传统的纤维化水凝设计原则.
- 这项研究将分子结构与临床血栓形成桥梁,有助于预测破裂风险评估和向治疗.
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