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• Ice growth speed is determined by atomic mobility and thermodynamic driving force. • A lower surface energy of ice crystal leads to a slower ice propagation. • Surface interaction rearranges ice crystal or graphene flakes during freezing. • Due to the rearrangement, ice grows faster in parallel to the graphene surface. The influence of thermodynamic and structural conditions on water-ice phase change process was investigated with consideration of graphene-water surface interactions for fundamental understanding and effective control of freezing propagation. The phase change propagation as well as structural and energetic properties during the phase change were examined by analyzing atomic data from molecular dynamics simulations. The freezing propagation speed is affected by the competition between atomic mobility and thermodynamic driving force for phase change, which causes an optimal temperature for fast ice growth to appear at 252 K. In addition, the water-ice interfacial energy, which depends on the orientation of the water-contacting ice surface, changes interfacial structural stability and thus freezing propagation, i.e., a higher interfacial energy leads to a faster ice propagation. Therefore, we suggest that the water-ice phase change propagation can be controlled by adjusting the orientation of ice crystal. The surface interactions, or graphene-water interactions in this research, affect the energetics near the water-surface interface. The energetic change rearranges the ice crystal or surface structures to reach the most stable ice-surface configuration or minimum energy state, in which the basal plane of the ice crystal is parallel with the graphene surface. As ice propagation is the slowest perpendicular to the basal plane, ice can grow faster parallel to graphene surface. The findings from this study provides insights to ice propagation control mechanisms for versatile freeze casting and its broader applications. [ABSTRACT FROM AUTHOR]

• Graphene in-plane phonon transport is largely suppressed by Si dopant scattering. • Graphene/SiO 2 interfacial transport is enhanced by Si doping (or lower resistance). • Weakened bonding by Si and their atomic mass increase the interfacial transport. • Effects of dopant's mass and interaction mismatch on phonon transport were found. • Doping effects on phonon kinetics were quantified using molecular dynamics. The effects of silicon (Si) doping on the in-plane and cross-plane thermal transport of suspended and silicon dioxide (SiO 2) supported graphene were investigated via molecular dynamics simulations. Due to the large mismatch in atomic mass and interaction with neighboring carbon atoms, Si can act as an effective phonon scatterer, thus suppressing the thermal transport. In this study, we evaluated the contributions of mass and interaction mismatches of Si dopants to the reduction in the in-plane thermal conductivity and the cross-plane thermal resistance through systematic control of the dopant's properties. 2% Si doping reduces the in-plane transport of suspended graphene by ~94% due to the increased scattering, while the SiO 2 -supported graphene is less affected. The phonon scattering by Si linearly increases with the Si content, and the interaction mismatch has a greater influence on the phonon kinetics during in-plane transport than the mass mismatch. In contrast, the cross-plane transport is enhanced by Si doping, decreasing the interfacial thermal resistance by ~30%, because of the stronger interfacial interactions by weaker in-plane bonding and the smaller atomic mass mismatch with the substrate material. The enhanced understanding of doping effects on thermal transport from this research is expected to provide insights for effective thermal transport control in various graphene structures. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Herein, a novel method is presented to establish equations for governing the motion of eggs on supporting rollers, enabling the usage of egg-classifying equipment as an important reference for optimally matching the forward speed and rotational speed of the egg and supporting rollers, respectively. The established theoretical equation was verified based on the screw lead theory and by performing real-world tests. Further, the differences between the theoretical and real speed values observed with respect to the obliquity angle of the egg and the egg shape index were analysed under identical supporting roller and rotating speed conditions. The deflection angle of the eggs rapidly increased during the initial 0–2 s but became stable thereafter. The real and theoretical speed values were similar when the egg shape index was approximately 78 and the obliquity angle was greater than 5°. The accuracy of the obtained theoretical velocity formula, which was verified using a support roller at a speed of 60 rpm, was confirmed based on the results of this study. In the future, the theoretical formula and experimental parameters can be derived based on this study. The length and speed of the roller can be adjusted, resulting in the delivery of eggs to the accurate position at the appropriate time using the automated grading and orientation equipment. • New approach to establish the equation of motion of eggs on supporting rollers. • Theory of screw lead and real tests to verify and produce derived theoretical speed. • Egg motion equation for air cell orientation development of egg product testing tools. [ABSTRACT FROM AUTHOR]