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In this study, we use some modified semiempirical quantum mechanics (SQM) methods for improving the molecular docking process. To this end, the three popular SQM Hamiltonians, PM6, PM6‐D3H4X, and PM7 are employed for geometry optimization of some binding modes of ligands docked into the human cyclin‐dependent kinase 2 (CDK2) by two widely used docking tools, AutoDock and AutoDock Vina. The results were analyzed with two different evaluation metrics: the symmetry‐corrected heavy‐atom RMSD and the fraction of recovered ligand‐protein contacts. It is shown that the evaluation of the fraction of recovered contacts is more useful to measure the similarity between two structures when interacting with a protein. It was also found that AutoDock is more successful than AutoDock Vina in producing the correct ligand poses (RMSD≤2.0 Å) and ranking of the poses. It is also demonstrated that the ligand optimization at the SQM level improves the docking results and the SQM structures have a significantly better fit to the observed crystal structures. Finally, the SQM optimizations reduce the number of close contacts in the docking poses and successfully remove most of the clash or bad contacts between ligand and protein.

The purpose of this research is to analyze the thermal behavior and kinetics of the pyrotechnic compositions including Al ? KClO 4 , Mg ? KClO 4 , Al ? Mg ? KClO 4 , MgAl ? KClO 4 and Al ? MgAl ? KClO 4 mixtures. The differential scanning calorimeter coupled with thermogravimetry analysis was employed to illustrate the reaction process of these pyrotechnic compositions. Moreover, the bomb calorimetry was utilized to compare experimental and theoretical heats of reaction. The apparent activation energy (E a ), frequency factor (A), the critical ignition temperature of thermal explosion and the self-accelerating decomposition temperature (T SADT ), were calculated using Kissinger approach. The results showed that the composition containing MgAl had the highest activation energy and frequency factor; however, the critical ignition temperature of their oxidation reaction was lowest value. In agreement with the theoretical value, the highest experimental heat of reaction for the composition MgAl/KClO 4 corresponds to the more complete combustion of metastable MgAl as an alloying mixture of Aluminum and Magnesium with equal proportions. These results suggest that benchmark values for an optimum designation and issues pertinent to the storage and handling of pyrotechnics containing Mg, Al and KClO 4 .

In this work, molecular dynamic simulation of the mixture of imidazolium based ionic liquids with alcohols is implemented in order to investigate mixing excess properties and some structural and physical properties of the mixture. Excess volumes and enthalpies are evaluated for 11 different mole fractions of ionic liquids at each 0.1, in the range of 0 to 1. Radial distribution function, cohesive energy density, potential of mean force, solvation energy, and diffusion coefficient are reported and analysed. The effects of the cationic alkyl chain length, in comparison with changes of the anions, on these properties are reported. Results reveal that the methanol molecule participates with its hydrophilic characteristics in the mixing process and tends to aggregate around anion part of the ionic liquids, especially in the case of Cl.