不同的Deborah数取决于从同质性到异质性的过渡
Dan Xu1, Yang Yang1, Lukas Emmerich2
1Sustainable Materials and Chemistry, Department of Wood Technology and Wood-based Composites, University of Göttingen, Büsgenweg 4, D-37077, Göttingen, Germany.
Nature communications
|September 26, 2023
概括
研究人员创建了混合水凝来模仿自然异质结构. 这项研究发现,在干燥过程中控制蒸发速度和Deborah数 (De) 影响了 xerogel 纤维中核心盖结构的形成.
科学领域:
- 材料科学 材料科学 材料科学
- 生物模拟学是一种生物模拟学.
- 聚合物科学 聚合物科学
背景情况:
- 不同质的结构在自然界中很常见,并激发了人造材料.
- 了解生物系统中这些复杂结构的形成是具有挑战性的.
- 混合水凝提供了一个模型系统来研究一般化的异质结构形成.
研究的目的:
- 为了研究混合水凝中异质核心盖结构的形成.
- 为了将结构形成与干燥过程参数相关联.
- 了解纤维素纳米晶体 (CNC) 在混合水凝中的作用.
主要方法:
- 用灵活的聚合物网络和嵌入式CNC制造混合水凝.
- 修改了空气干燥工艺以控制蒸发.
- 使用显微镜和物理测量分析结构形成.
- 形态与Deborah数 (De) 和相对湿度的相关性.
主要成果:
- 异质的核心 - 盖结构已成功地在凝纤维中形成.
- 结构的形成取决于干燥过程中的相对蒸发速度.
- 德博拉数 (De) 从大值转变为小值,大约是De=1,这是一个关键的转折点.
- 该机制涉及相对湿度依赖的玻璃过渡行为.
结论:
- 该研究提供了对混合水凝中异质核心盖结构的形成的见解.
- 控制干燥参数,特别是蒸发速度和De,可以设计这样的结构.
- 这些结构影响水的透和吸收特性.
- 这些发现有助于生物学设计,其灵感来源于本地异质结构.
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