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Thermal resistance effect on anomalous diffusion of molecules under confinement.

ABSTRACT: Diffusion is generally faster at higher temperatures. Here, a counterintuitive behavior is observed in that the movement of long-chain molecules slows as the temperature increases under confinement. This report confirms that this anomalous diffusion is caused by the "thermal resistance effect," in which the diffusion resistance of linear-chain molecules is equivalent to that with branched-chain configurations at high temperature. It then restrains the molecular transportation in the nanoscale channels, as further confirmed by zero length column experiments. This work enriches our understanding of the anomalous diffusion family and provides fundamental insights into the mechanism inside confined systems.

SUBMITTER: Yuan J

PROVIDER: S-EPMC8166051 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Thermal resistance effect on anomalous diffusion of molecules under confinement.

Yuan Jiamin J Liu Zhiqiang Z Wu Yimo Y Han Jingfeng J Tang Xiaomin X Li Chengbin C Chen Wei W Yi Xianfeng X Zhou Jian J Krishna Rajamani R Sastre German G Zheng Anmin A

Proceedings of the National Academy of Sciences of the United States of America 20210501 21

Diffusion is generally faster at higher temperatures. Here, a counterintuitive behavior is observed in that the movement of long-chain molecules slows as the temperature increases under confinement. This report confirms that this anomalous diffusion is caused by the "thermal resistance effect," in which the diffusion resistance of linear-chain molecules is equivalent to that with branched-chain configurations at high temperature. It then restrains the molecular transportation in the nanoscale ch ...[more]

PMID: 34001593

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