剪切对体群生长的影响:SANS和USANS研究
Chris Muzny1, Liliana de Campo2, Anna Sokolova2
1Applied Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, CO 80305, USA.
概括
剪切场破坏了二氧化颗粒凝结,改变了集群大小和粘度. 微角散射揭示了微观变化,有助于剪切合体悬浮的理论模型.
科学领域:
- 合体和表面科学科学
- 材料科学 材料科学 材料科学
- 类风病学 类风病学 类风病学
背景情况:
- 体悬浮物如二氧化/水可以形成凝网络.
- 外部力量,如剪切,可以显著改变这些凝的结构和特性.
- 了解凝和剪切之间的相互作用对于控制材料特性至关重要.
研究的目的:
- 为了研究在中断凝期间在剪切下的/水集群的时间演变.
- 了解剪切合体凝粘度变化的显微基础.
- 从散射实验中提供结构数据,以告知理论模型.
主要方法:
- 使用了8.3nm粒子溶液 (Ludox) 与启动的凝.
- 在恒定切割速率为250s-1的情况下应用了Couette切割场.
- 采用统一的小角度中子散射 (SANS) 和超小角度中子散射 (USANS) 程序来探测从纳米到微米尺度的结构.
主要成果:
- 散射数据捕获了随着时间的推移受到剪切作用的合体集群中的结构变化.
- 调整了依赖时间的分散强度,以估计有效的集群体积分和大小演变.
- 在剪切的体悬浮液中证明了结构变化和粘度行为之间的联系.
结论:
- 剪切场显著影响了/水凝集群的时间演变和结构.
- 分散技术为剪切的合体系统提供了重要的结构洞察力.
- 一个理论框架可以根据集群体体积分和尺寸变化来预测粘度.
关键词:
没有SANS,就没有SANS.美国人 美国人应用剪切切削的方法合体二氧化的合体二氧化微米尺度上的微米尺度.延迟凝制成的凝.微角中子散射是一种小角度的中子散射.结构因子的导出结构因子的导出时间依赖的现象.超小角度中子散射超小角度中子散射粘度 粘度 粘度 粘度 粘度体积分数的体积分数是什么更多相关视频
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