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As two necessary steps in phase-field simulation, parameters calculation and results storage play an important role to ensure the accuracy of simulation results. A strategy of parameters calculation and results storage was presented for phase-field simulation in α-Mg dendrite growth of Mg-5wt%Zn alloy under isothermal solidification. Based on the phase diagram and empirical formulas, key parameters of the phase-field model (equilibrium partition coefficient k, liquidus slope m, solutal diffusion coefficient in liquid Dl , solutal diffusion coefficient in solid Ds , etc.) can be obtained. Both structured grid and structured point storage methods can be used to store simulation results, but using the latter method will reduce about 60% storage space and 37.5% storage time compared to the former. Finally, convergent simulation results of α-Mg dendrite growth were obtained and in good agreement with the optical micrograph of experimental results, which verify the accuracy of parameters and stability of storage methods.

We report here two new centimetric two-dimensional Dion–Jacobson bromide double perovskites with outstanding stability, strong photocurrent responses and bluish-white broadband emission.

We report here a new two-dimensional bimetallic double perovskite with reversible thermochromism, enhanced electrical conductivity and outstanding stability.

We present the assembly of a S-ligated Dy–SMM unit into a discrete molecule and polymeric chain, and the modulation of magnetic dynamics.

In this paper, a new aromatic diamine monomer 4,4′-(2,6-naphthalenediyl)bis[benzenamine]) (NADA) was synthesized and a series of modified PI films containing naphthalene ring structure obtained by controlling the molar ratio of NADA monomer, ternary polymerization with 4,4′-oxydianiline (ODA), and pyromellitic dianhydride (PMDA). The effects of the introduction of the naphthalene ring on the free volume and various properties of PI were investigated by molecular dynamic simulations. The results show that the comprehensive properties of the modified films are all improved to some extent, with 5% thermal weight loss temperature (Td5%) of 569 °C, glass transition temperature (Tg) of 381 °C, tensile strength of 96.41 MPa, and modulus of elasticity of 2.45 GPa. Dielectric property test results show that the dielectric constant (Dk) of the film at 1 MHz is reduced from 3.21 to 2.82 and dielectric loss (Df) reduced from 0.0091 to 0.0065. It is noteworthy that the PI-1 dielectric constant is reduced from 3.26 to 3.01 at 10 GHz with only 5% NADA doping, which is expected to yield the best ratio and provide the possibility of industrial production.