As candidates, liquid metal composites (LMCs) exhibit tunable physical and functional properties at various scales, broadening applications in flexible electronics. Herein, by the synergistic effect of metal coordination and acoustic field, a liquid metal composite (LMEPC) with tunable gradient structure is prepared. The gradient and bicontinuous structures of LMPEC result in the initial thermal and electrical conductivity anisotropy without pre-activation. The size of LM particles (LMPs) can be controlled from nano to micro scale due to the synergistic effect of metal coordination and acoustic field application, resulting in a transformation of the gradient structure. LMEPC exhibits enhanced electrical conductivity (0.0540 Ω), thermal conductivity (1.317 W K −1 m −1 ), mechanical property (1847.3 MPa), and programmable shape performance. These capabilities enable the design of multifunctional electronics. This work provides a new strategy to control the gradient structure of LMCs by the induction of metal coordination to broaden the horizon of applications.
Contact electrification (CE) is a common physical phenomenon, and its mechanisms for solid–solid and liquid–solid cases have been widely discussed. However, the studies about liquid–liquid CE are hindered by the lack of proper techniques. Here, a contactless method is proposed for quantifying the charges on a liquid droplet based on the combination of electric field and acoustic field. The liquid droplet is suspended in an acoustic field, and an electric field force is created on the droplet to balance the acoustic trap force. The amount of charges on the droplet is thus calculated based on the equilibrium of forces. Further, the liquid–solid and liquid–liquid CE are both studied by using the method, and the latter is focused. The behavior of negatively precharged liquid droplet in the liquid–liquid CE is found to be different from that of the positively precharged one. The results show that the silicone oil droplet prefers to receive negative charges from a negatively charged aqueous droplet rather than positive charges from a positively charged aqueous droplet, which provides a strong evidence about the dominant role played by electron transfer in the liquid–liquid CE.
The digestibility of starch-based foods is receiving increased attention. To date, the full understanding of how including L-theanine (THE) can modify the structural and digestive properties of starch has not been fully achieved. Here, we investigated the multi-scale structure and digestibility of maize starch (MS) regulated by THE in ultrasound field and the molecular interactions . Ultrasound disrupted the structure of starch granules and opened the molecular chains of starch, promoting increased THE binding and producing more low-order or disordered crystal structures. In this case, the aggregation of starch molecules, especially amylose , was reduced, leading to increased mobility of the systems. As a result, the apparent viscosity, G', and G" were significantly decreased, which retarded the starch regeneration. Density functional theory calculations indicated that there were mainly non-covalent interactions between THE and MS, such as hydrogen bonding and van der Waals forces. These interactions were the main factors contributing to the decrease in the short-range ordering, the helical structure, and the enthalpy change (ΔH) of MS. Interestingly, the rapidly digestible starch (RDS) content of THE modified MS (MS-THE-30) decreased by 17.89 %, while the resistant starch increased to 26.65 %. These results provide new strategies for the safe production of resistant starch.
危险品化学品经营许可证（带存储）