编织和非编织面罩材料的显微镜:对颗粒过的含义
Edward P Vicenzi1,2, Scott Whittaker3, Jamie L Weaver1,2
1Museum Conservation Institute, Smithsonian Institution, 4210 Silver Hill Rd., Suitland, MD 20746, USA.
概括
像N95呼吸器这样的无材料的纤维直径比织物更小,更多样化. 微X射线计算机断层扫描 (μXCT) 提供了一种用于过建模的新方法来测量织物特性.
科学领域:
- 材料科学 材料科学 材料科学
- 织工程 织工程 织工程
- 生物医学工程 生物医学工程
背景情况:
- 了解织物微观结构对于优化口罩和呼吸器中的颗粒过至关重要.
- 织物和非织物具有独特的结构特征,影响其性能.
研究的目的:
- 描述和比较各种织物和非织物织物的微观结构特性.
- 评估微型X射线计算机断层扫描 (μXCT) 对织物分析的实用性.
- 提出新的指标来评估面料在过应用中的适用性.
主要方法:
- 使用可见光显微镜,扫描电子显微镜 (SEM) 和微型X射线计算机断层扫描 (μXCT).
- 纤维直径分布,织物厚度和固体空间体积被量化.
- 开发了一种用于法兰织物的新厚度测量方法,考虑了升高的纤维.
主要成果:
- 非织造材料 (外科口罩,N95呼吸器) 的平均纤维直径为≈3μm,分布偏斜.
- 织物表现出更大的平均纤维直径 (>15微米) 与正常分布.
- N95过材料 (1093微米) 比织物 (420650微米) 显著更厚.
- μXCT提供了面料多孔性和表面积/体积的定量,非破坏性测量.
结论:
- 微观结构的差异,特别是纤维直径分布和厚度,使无布与织造布区分开来.
- 表面织物同变性和表面积/体积比是粒子过建模的有价值参数.
- μXCT 是一个强大的工具,用于与过性能相关的非破坏性织物表征.
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