在电子显微镜中观察未涂层木材样本的临界电压的确定
Monika Sarvašová Kvietková1, Ondřej Dvořák1, Kryštof Kubista1
1Department of Wood Processing and Biomaterials, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 1176, 16500 Prague, Czech Republic.
Materials (Basel, Switzerland)
|January 25, 2025
概括
使用电子显微镜 (EM) 观察未涂层木材样本现在是可行的. 这项研究发现,1 kV至1.6 kV的临界电压范围允许有效的成像,加速研究并降低各种木材物种的成本.
科学领域:
- 木材科学 木材科学 木材科学
- 材料科学 材料科学 材料科学
- 显微镜的使用方法
背景情况:
- 电子显微镜 (EM) 对于木材微观结构分析至关重要.
- 表面充电阻碍了EM中未涂层木材样本的观察.
- 开发用于未涂层样本分析的方法对于效率至关重要.
研究的目的:
- 为了确定有效观察未涂层木材样本的临界电压.
- 为了评估EM分析的可行性,而不是样本涂层在不同的木材种类.
- 为了优化未涂层木材的SEM成像参数.
主要方法:
- 测试了来自十个物种的未涂层木材样本: Acacia,树,树,灰树,树,热木,Garapa,Ipé,Merbau和Massaranduba.
- 研究了各种表面准备技术,包括圆形,手工和微.
- 评估了二次电子探测器 (SED) 和回散电子探测器 (BSED) 的性能.
主要成果:
- 在所有测试物种中,在1kV至1.6kV的电压范围内,可以有效地观察未涂层木材样本.
- 二次电子检测在低电压下对未涂层的样品证明是最佳的.
- 涂层样本提供了更好的信号噪声比,在更高的电压下检测回散电子.
结论:
- 未涂层木材样本的电子显微镜是实用且具有成本效益的,需要特定的低压范围.
- 这些发现通过简化样本准备来加速木质微观结构的研究和应用.
- 这项研究为使用EM分析其他木种和木材材料提供了基础.
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