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In the present study, adsorption of helium, neon, argon and binary mixtures of one of them with hydrogen on (5, 5) armchair silicon nanotube at Temperatures of 50, 100 and 150K and Pressures of 1, 5, 7, 10 and 15MPa were studied. For each binary mixture three different mole fractions of hydrogen were examined. Canonical Monte Carlo simulation by ab-initio calculation was employed for studding the adsorption of above gases on single-walled silicon nanotubes (SW-Si-NTs). The interaction energy of gases with the surfaces of the single Si-NTs obtained from quantum mechanics calculations was fitted to an exact potential functions used for simulating the system. Lennard-Jones potential was used for gas-gas and Morse potential was used for gas-silicon nanotubes interaction. The work was carried out at several temperatures and pressures by using Canonical-Monte-Carlo or CMC simulation in order for studding the effect of temperature and pressure on gas adsorption. The adsorption results showed that by increasing the pressure and decreasing the temperature, the amount of adsorption increases. It was concluded that among the rare gases discussed helium was lowest impact on hydrogen adsorption in a mixture of helium and hydrogen.

Parkinson's disease (PD) is the second most common neurodegenerative disorder, affecting 1.5% of the global population over 65 years of age. Levodopa (LD), a phenolic compound, is the most frequently prescribed drug for the treatment of PD. In this work, we have studied the LD adsorbed covalently and non-covalently on M41-APTES using B3LYP and M06-2X method and 6-31G * * at different distances. The 1 H and 13 C, 17 O and 15 N nuclear magnetic resonance (NMR), ChelpG and NBO were carried out by DFT method for M41-APTES-LD at 1.5 and 3.5 Å. Density functional theory (DFT) calculations were performed using GAMESS-US package of program. In this work the 1H, 13 C, NMR parameters and iso , aniso , and , for M41-APTES-LD at 1.5 Å and 3.5 Å have been calculated. We have shown the N11-N92 and N92-N95 bond has high hyper-conjugation energy than other bonds.

Introduction:: MCM-41 was synthesized using the sol-gel method. Then two new transition metal complexes of Nickel (II) and Vanadium (IV), were synthesized by immobilization of adenine (6-aminopurine) into MCM-41 mesoporous. The compounds have been characterized by XRD, TGA, SEM, AAS and FT-IR spectral studies. Using these catalysts provided an efficient and enantioselective procedure for oxidation of sulfides to sulfoxides and oxidative coupling of thiols to their corresponding disulfides using hydrogen peroxide at room temperature. Materials and Methods:: To a solution of sulfide or thiol (1 mmol) and H2O2 (5 mmol), a determined amount of the catalyst was added. The reaction mixture was stirred at room temperature for the specific time under solvent free conditions. The progress of the reaction was monitored by TLC using n-hexane: acetone (8:2). Afterwards, the catalyst was removed from the reaction mixture by centrifugation and, then, washed with dichloromethane in order to give the pure products. Results:: All the products were obtained in excellent yields and short reaction times indicating the high activity of the synthesized catalysts. Besides, the catalysts can be recovered and reused for several runs without significant loss in their catalytic activity. Conclusion:: These catalytic systems furnish the products very quickly with excellent yields and VO-6AP-MCM-41 shows high catalytic activity compared to Ni-6AP-MCM-41.

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