In the current study, the compound 4,4-dimethoxychalcone (DMC) was structurally studied and analyzed by in silico approach against M^pro to investigate its inhibitory potential. The molecular structure of the compound was confirmed by the single crystal X-ray diffraction studies. The crystal structure packing is characterized by various hydrogen bonds, C-H…π and π…π stacking. Intermolecular interactions are quantified by Hirshfeld surface analysis and the electronic structure was optimized by DFT calculations; results are in agreement with the experimental studies. Further, DMC was virtually screened against SARS-CoV-2 main protease (PDB-ID: 6LU7) using molecular docking, and molecular dynamics (MD) simulations to identify its inhibitory potential. A significant binding affinity exists between DMC and M^pro with a -6.00 kcal/mol binding energy. A MD simulation of 30ns was carried out; the results predict DMC possessing strong binding affinity and hydrogen-bonding interactions within the active site during the simulation period. Therefore, based on the results of the current investigation, it can be inferred that a DMC molecule may be able to inhibit M^pro of COVID-19.

In this research, acheiving submicrocrystalline structure in commercially pure Al is investigated using severe plastic deformation (SPD) method named constrained groove pressing (CGP). In order to find a procedure that acts more effective in grain refinement and mechanical properties enhancement, three experimental procedures were defined and carried out. The procedures were defined by variables of die groove angle (45° and 50°) and using Cu covering sheets at top and down of the specimens instead of rigid die surface as a lubricant. Grain refinement during CGP process was investigated by William-hall analysis on X-Ray diffraction pattern and scanning electron microscopy (SEM). The results show that CGP process in all three procedures can severely refine the microstructure to an ultra-fine grained (UFG) structure with less than 1 micron grain size. Although grain refinement rate in die with 50° groove angle is higher but because of facility of applying extra CGP passes in 45° groove angle die with covering sheets (procedure 2), final grain size in procedure B is lesser. Mechanical properties of CGPed samples was investigated by tensile and hardness tests and the results show that at primary passes in all procedures strength-related properties increases significantly through a decrease in elongation, but at subsequent passes this behaviuor is diffentent for each procedure.