Molecular dynamics (MD) simulations and biased MD simulation were carried out for the neutral form of Paracetamol inserted in fully hydrated dipalmitoylphosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) lipid bilayers. For comparison, fully hydrated DMPC and DPPC lipid bilayers were also simulated separately without Paracetamol. The simulation time for each system was 50 ns. At two concentrations of Paracetamol, various properties of the lipid bilayer such as area per lipid, order parameter, diffusion coefficient, radial distribution function, electrostatic potential, mass density and hydrogen bonds have been calculated. Also, the convergence in time of the free energy profile of the Paracetamol along a DPPC bilayer normal was calculated by umbrella sampling method. From the obtained results, it can be concluded that neutral form of Paracetamol shows a generally similar behaviour in DPPC and DMPC lipid bilayers. It was shown that the addition of Paracetamol causes a decrease in tail order parameter of both DPPC and DMPC lipid bilayers and the tail of Paracetamol adopts an inward orientation in the lipid bilayers. Also from the free energy profile, the high penetration barrier in the bilayer centre was determined.

Naproxen and relafen, as nonsteroidal antiinflammatory drugs, were simulated in neutral and charged forms and their effects on a lipid bilayer membrane were investigated by molecular dynamics simulation using Groningen machine for chemical simulations software (GROMACS). Simulation of 10 systems was performed, which included different dosages of the drug molecules, naproxen and Relafen, in charged and neutral forms, and a mixture of naproxen and Relafen in neutral forms. The effects of the mixture and the individual drugs' dosages on membrane properties, such as electrostatic potential, order parameter, diffusion coefficients, and hydrogen bond formation, were analyzed. Hydration of the drugs in the membrane system was investigated using radial distribution function analysis. Using fully hydrated dimyristoylphosphatidylcholine (DMPC) as a reference system, 128 lipid molecules and water molecules were simulated exclusively, and the same simulation technique was performed on 10 other systems, including drug mixtures and a DMPC membrane. Angular distributions of lipid chains of the membrane were calculated, and the effects of the drug insertion and chain orientation in the membrane were evaluated.

Electroless Ni-P-Al 2 O 3 nanocomposite coating was obtained by adding alumina nanoparticles to the nickel electroless plating bath. Particles of y74 nm in size were selected in order to study the influence of the particle incorporation to the coating properties. The composite coatings were heat treated at 200, 400 and 600uC for 1 h (60 min) and structural changes were evaluated by X-ray diffraction (XRD) analysis. Surface morphology of composite deposits has been investigated by scanning electron microscopy (SEM). Electrochemical impedance spectroscopy and potentiodynamic polarisation method have been used to evaluate the coating performance before and after heat treatment. The Ni-P electroless coating contains 9?18 wt-%P while the alumina composite coating contains 8?30 wt-%P. The composite coatings, which contains alumina nanoparticles, exhibit better properties of hardness and corrosion resistance.

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