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带有碳纳米管的空气-水接口的粘性弹性
Shing-Yun Chang1, Sahil R Vora1, Charles D Young1
1Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT, 06269, USA.
The European physical journal. E, Soft matter
|March 8, 2024
概括
与振荡屏障 (OB) 相比,双角透过 (BT) 方法为碳纳米管 (CNT) 载荷接口的表征提供了优越的应变控制. BT产生更高的信号噪声比率,揭示了CNT接口的关键粘弹性特性.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 类风病学 类风病学 类风病学
背景情况:
- 碳纳米管 (CNTs) 由于其独特的特性,被用于各种应用.
- 描述带有粒子接口的粘性弹性对于理解它们的行为至关重要.
- 传统方法在精确控制和数据采集方面可能存在局限性.
研究的目的:
- 为了比较两种实验方法的有效性,以表征载有CNT的空气-水接口.
- 评估振荡屏障 (OB) 和双角透过 (BT) 方法的性能.
- 在不同的条件下确定CNT接口的粘弹性特性.
主要方法:
- 使用了带振荡屏障的朗迈尔-波克尔斯 (LP) 槽 (OB方法).
- 开发并采用定制的双孔通道 (BT) 方法,将LP通道与风度计和双孔固定装置集成在一起.
- 进行快速里埃转换 (FFT) 分析以评估信号噪声比 (SNR) 以进行方法比较.
主要成果:
- 与OB方法相比,BT方法显示出优越的应变控制和显著更高的SNR.
- 该OB方法显示,面切模量 (39-57mN/m) 与应变 (1-3%) 增加,并且在0.5%的应变下缺乏线性粘弹性体制.
- 通过BT方法,确定了低于0.1%的剪切应变的线性状态,其模量从96降至2 mN/m,随着应变从0.025%增加到10%,该模量从96降至2 mN/m.
结论:
- 基于流量计的BT方法在标准化准备和调节带有颗粒的接口方面更有效,特别是在高覆盖率下.
- 与OB方法相比,BT方法提供了更可靠和更详细的界面粘性弹性的表征.
- 精确的应变控制对于在负载CNT接口中观察线性粘弹性调节至关重要.
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