Structural features and thermal stability of hollow-core Si nanowires: A molecular dynamics study

AbstractTo understand antiwear phenomena in motor engines at the atomic level and provide evidence inselecting future ashless wear inhibitors, we studied the thermal stability of the self-assembled monolayer(SAM) model for dithiophosphate (DTP) and dithiocarbamate (DTC) molecules on the iron oxidesurface using molecular dynamics. The interactions for DTP, DTC and Fe2O3 are evaluated based on aforce field derived from fitting to ab initio quantum chemical calculations of dimethyl DTP (and DTC)and Fe(OH)2(H2O)2-DTP (DTC) clusters. MD simulations at constant-NPT are conducted to assesrelative thermal stabilities of the DTP and DTC with different pendant groups (n-propyl, i-propyl, npentyl.and i-pentyl). To investigate frictional process, we employ a steady state MD method, in whichone of the Fe2O3 slabs maintained at a constant linear velocity. We obtain the time averaged normaland frictional forces from the interatomic forces. Then, we calculated the friction coefficient at theinterface between SAMs of DTP and the confined lubricant, hexadecane, to assess the shear stability ofDTPs with different pendant groups.

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Effects of Ce+Gd on the structural features and thermal stability of iron-boron-phosphate glasses

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2017.08.060 ◽

2017 ◽

Vol 201 ◽

pp. 170-179 ◽

Cited By ~ 1

Author(s):

Fu Wang ◽

Zhiwei Fang ◽

Hong Wang ◽

Qilong Liao ◽

Hanzhen Zhu

Keyword(s):

Thermal Stability ◽

Structural Features ◽

Phosphate Glasses ◽

Boron Phosphate ◽

Thermal Stability Of

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A Possible Mechanism of Graphene Oxide to Enhance Thermostability of D-Psicose 3-Epimerase Revealed by Molecular Dynamics Simulations

International Journal of Molecular Sciences ◽

10.3390/ijms221910813 ◽

2021 ◽

Vol 22 (19) ◽

pp. 10813

Author(s):

Congcong Li ◽

Zhongkui Lu ◽

Min Wang ◽

Siao Chen ◽

Lu Han ◽

...

Keyword(s):

Molecular Dynamics ◽

Thermal Stability ◽

Graphene Oxide ◽

Md Simulations ◽

Strong Interactions ◽

Limiting Factor ◽

Active Site Residues ◽

Detailed Mechanism ◽

Dynamics Simulations ◽

Thermal Stability Of

Thermal stability is a limiting factor for effective application of D-psicose 3-epimerase (DPEase) enzyme. Recently, it was reported that the thermal stability of DPEase was improved by immobilizing enzymes on graphene oxide (GO) nanoparticles. However, the detailed mechanism is not known. In this study, we investigated interaction details between GO and DPEase by performing molecular dynamics (MD) simulations. The results indicated that the domain (K248 to D268) of DPEase was an important anchor for immobilizing DPEase on GO surface. Moreover, the strong interactions between DPEase and GO can prevent loop α1′-α1 and β4-α4 of DPEase from the drastic fluctuation. Since these two loops contained active site residues, the geometry of the active pocket of the enzyme remained stable at high temperature after the DPEase was immobilized by GO, which facilitated efficient catalytic activity of the enzyme. Our research provided a detailed mechanism for the interaction between GO and DPEase at the nano–biology interface.

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