Initial Stage Carbonization of γ-Fe(100) Surface in C2H2 under High Temperature: A Molecular Dynamic Simulation

In the present work, initial stage carbonization of γ-Fe(100) surface in C2H2 from 1000 K to 1600 K has been investigated by a molecular dynamic (MD) simulation, based on which the atomic mechanism of initial stage carbonization was provided. The absorption of C and H atoms during the carbonization process under different temperatures was analyzed. The related distributions of C and H atoms in carbonized layer were provided. The results manifested that higher temperature enhanced the inward diffusion of C and H, meanwhile caused the desorption of H atom. Furthermore, the effect of preset polycrystal γ-Fe on the carbonization process has been discussed, indicating a promoting role to the absorption and inner diffusion of C and H atom. The results of this study may support the optimal design of high-performance steel to some extent.

Studi Dinamika Molekul Stabilisasi Metaloproteinase Matriks 9 oleh Asam Kafeat

Caffeic acid, a cathecol-containing phytochemical found in coffee, has been reported as a potent matrix metalloproteinase 9 (MMP9) inhibitor. The IC50 value of caffeic acid as MMP9 inhibitor could reach below 20 nM. The research presented in this article employed molecular dynamics simulations to unravel the atomic mechanism of the MMP9 inhibition by caffeic acid. Molecular dynamics simulations of MMP9 for 10 ns using YASARA-Structure were performed with and without caffeic acid as the studied ligand. The results showed that caffeic acid stabilized the stucture of the MMP9.