Dimethyl Sulfoxide and Sodium Chloride Modulate the Crystal Structure in PMIA to Enhance Dyeing Performance: Molecular Dynamics Simulation and Experimental Investigations.

The widespread use of meta-aramid (PMIA) is limited by its poor dyeing performance, and researchers often struggle to qualitatively and quantitatively assess its microscopic structural regulation when attempting to improve dyeing performance. Herein, DMSO/NaCl is chosen to synergistically modulate the structure of PMIA to improve its dyeing properties in combination with experiments and simulations. Initially, characterization and color testing reveal that the DMSO/NaCl combination induces structural changes in the amorphous regions of the PMIA fiber, improving the dispersion of the dye solution.

Theoretical Investigation into Polymorphic Transformation between β-HMX and δ-HMX by Finite Temperature String.

Polymorphic transformation is important in chemical industries, in particular, in those involving explosive molecular crystals. However, due to simulating challenges in the rare event method and collective variables, understanding the transformation mechanism of molecular crystals with a complex structure at the molecular level is poor. In this work, with the constructed order parameters (OPs) and K-means clustering algorithm, the potential of mean force (PMF) along the minimum free-energy path connecting -HMX and -HMX was calculated by the finite temperature string method in the collective variables (SMCV), the free-energy profile and nucleation kinetics were obtained by Markovian milestoning with Voronoi tessellations, and the temperature effect on nucleation was also clarified.

Theoretical Analysis of Stacking Fault Energy, Elastic Properties, Electronic Properties, and Work Function of MnCoCrFeNi High-Entropy Alloy.

The effects of different Mn concentrations on the generalized stacking fault energies (GSFE) and elastic properties of MnCoCrFeNi high-entropy alloys (HEAs) have been studied via first-principles, which are based on density functional theory. The relationship of different Mn concentrations with the chemical bond and surface activity of MnCoCrFeNi HEAs are discussed from the perspectives of electronic structure and work function. The results show that the plastic deformation of MnCoCrFeNi HEAs can be controlled via dislocation-mediated slip.

Molecular dynamics study on structural modulation and dyeing property optimization of meta-aramid in a DMSO/electrolyte system.

Meta-aramid (PMIA) fabrics are typically problematic to dye owing to their extremely crystalline structure and high compactness. Herein, Dimethyl sulfoxide (DMSO) and electrolyte as hydrogen bond regulators were selected to improve the dyeability of PIMA dyed with cationic dyes. The PMIA shows both high dyeing and mechanical properties as a result of the synergistic effect of DMSO and electrolyte in the system, which destructs hydrogen bonding networks and increase interaction energy density between dye molecules and PMIA, confirmed by a series of characterization and molecular dynamics simulations.

Did carbon emission trading scheme improve energy use in China? An integrated approach based on SCM and threshold regression.

The analysis of energy use not only sheds light on lightening the increasing pressures from energy systems but also improves the flexibility and reliability of power systems. As the highest carbon emission country in the world, detailed evaluation of China's carbon emission trading scheme (ETS) on the energy use is sensitive to energy sectors and highlights the importance of energy utilization in current society. Yet, because of the presence of a possible discontinuity caused by policy implementation, this study uses synthetic control method (SCM) to confirm whether there is a cutoff for energy use after the ETS implementation.

Exploration of D0-Type AlTM(TM = Sc, Ti, V, Zr, Nb, Hf, Ta): Elastic Anisotropy, Electronic Structures, Work Function and Experimental Design.

The structural properties, elastic anisotropy, electronic structures and work function of D0-type AlTM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the AlZr is the most thermodynamic stable compound.

Investigation on MgSb/MgSi Heterogeneous Nucleation Interface Using Density Functional Theory.

In this study, the cohesive energy, interfacial energy, electronic structure, and bonding of MgSi (111)/MgSb (0001) were investigated by using the first-principles method based on density functional theory. Meanwhile, the mechanism of the MgSb heterogeneous nucleation potency on MgSi grains was revealed. The results indicated that the MgSb (0001) slab and the MgSi (111) slab achieved bulk-like characteristics when the atomic layers N ≥ 11, and the work of adhesion of the hollow-site (HCP) stacking structure (the interfacial Sb atom located on top of the Si atom in the second layer of MgSi) was larger than that of the other stacking structures.