Room temperature on-surface synthesis of two-dimensional imine polymers at the solid/liquid interface: concentration takes control

Thermal energy storage units that utilize phase change materials have been widely employed to balance temporary temperature alternations and store energy in many engineering systems. In the present paper, an operational approach is proposed to the Tau method with standard polynomial bases to simulate the phase change problems in latent heat thermal storage systems, that is, the two-dimensional solidification process in rectangular finned storage with a constant end-wall temperature. In order to illustrate the efficiency and accuracy of the present method, the solid-liquid interface location and the temperature distribution of the fin for three test cases with different geometries are obtained and compared to simplified analytical results in the published literature. The results indicate that using a two-dimensional numerical approach can predict the solid-liquid interface location more accurately than the simplified analytical model in all cases, especially at the corners.

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Phase-Field Microstructure Solidification of Al–2 wt% Si Alloys

Journal of Engineering Materials and Technology ◽

10.1115/1.4044280 ◽

2019 ◽

Vol 142 (1) ◽

Author(s):

J. B. Allen

Keyword(s):

Directional Solidification ◽

Phase Field ◽

Maximum Concentration ◽

Dendritic Growth ◽

Interface Energy ◽

Liquid Interface ◽

Two Dimensional ◽

Solid Liquid Interface ◽

Solid Liquid ◽

Dilute Alloy

In this work, we develop one- and two-dimensional phase-field simulations to approximate dendritic growth of a binary Al–2 wt% Si alloy. Simulations are performed for both isothermal as well as directional solidification. Anisotropic interface energies are included with fourfold symmetries, and the dilute alloy assumption is imposed. The isothermal results confirm the decrease in the maximum concentration for larger interface velocities as well as reveal the presence of parabolic, dendrite tips evolving along directions of maximum interface energy. The directional solidification results further confirm the formation of distinctive secondary dendritic arm structures that evolve at regular intervals along the unstable solid/liquid interface.

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Dynamic host–guest behavior in halogen-bonded two-dimensional molecular networks investigated by scanning tunneling microscopy at the solid/liquid interface

Nanoscale Advances ◽

10.1039/d0na00616e ◽

2020 ◽

Vol 2 (10) ◽

pp. 4895-4901

Author(s):

Yoshihiro Kikkawa ◽

Mayumi Nagasaki ◽

Emiko Koyama ◽

Seiji Tsuzuki ◽

Thierry Fouquet ◽

...

Keyword(s):

Scanning Tunneling Microscopy ◽

Liquid Interface ◽

Molecular Networks ◽

Scanning Tunneling ◽

Two Dimensional ◽

Tunneling Microscopy ◽

2D Structure ◽

Solid Liquid Interface ◽

Solid Liquid

Dynamic host–guest behavior is investigated in halogen-bonded molecular networks, and the change in the 2D structure due to guest inclusion is revealed by scanning tunneling microscopy at the solid/liquid interface.

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