nanoparticles made of biodegradable polymers has become the best approach for nanoparticle making due to their compatibility with the human body. new glycerol adipate polymers with hydroxyl group substituted with different percent of acyl group, sited as figures within the abbreviated name in the text, and triptophan were synthesized and proposed to be used in the preparction of dexamethason ph...

Self-assembled monolayers (SAMs) of alkylsiloxanes on elastomeric PDMS (polydimethylsiloxane) were used as model systems to study interactions between surfaces. Surface free energies (gammasv) of these chemically modified surfaces were estimated by measuring the deformations that resulted from the contact between small semispherical lenses and flat sheets of the elastomer under controlled loads...

The free-energy profile of a reaction can be estimated in a molecular-dynamics approach by imposing a mechanical constraint along a reaction coordinate (RC). Many recent studies have shown that the temperature can greatly influence the path followed by the reactants. Here, we propose a practical way to construct the minimum-energy path directly on the free-energy surface at a given temperature....

We applied the solvation models SM8, SM8AD, and SMD in combination with the Minnesota M06-2X density functional to predict vacuum-water transfer free energies (Task 1) and tautomeric ratios in aqueous solution (Task 2) for the SAMPL2 test set. The bulk-electrostatic contribution to the free energy of solvation is treated as follows: SM8 employs the generalized Born model with the Coulomb field ...

We have investigated changes in water properties when deforming an initially spherical cavity into an oblate ellipsoid of equal volume in liquid water. The purely hydrophobic cavity has an initial thermal radius of 6.45 A and is flattened out to an oblate ellipse with a thickness corresponding to one layer of methane molecules. The water-solute interactions are modeled by a repulsive, single-si...

Strain can greatly modify the state of a crystal surface, and cause reconstruction and deconstruction phase transitions even at constant temperature. We carried out test calculations of surface free energy differences that illustrate the phenomenon, and parallel simulations that demonstrate directly how the prototype reconstruction of Au(111) should change under bending-induced strain. That sho...

The equilibrium and fluctuation methods for determining the surface tension, sigma, and bending modulus, kappa, of a bilayer membrane with a fixed projected area are discussed. In the fluctuation method the elastic coefficients sigma and kappa are measured from the amplitude of thermal fluctuations of the planar membrane, while in the equilibrium method the free energy required to deform the me...

Plant surfaces have been found to have a major chemical and physical heterogeneity and play a key protecting role against multiple stress factors. During the last decade, there is a raising interest in examining plant surface properties for the development of biomimetic materials. Contact angle measurement of different liquids is a common tool for characterizing synthetic materials, which is ju...

We present a Ginzburg-Landau theory of solvation of ions in polar binary mixtures. The solvation free energy arising from the ion-dipole interaction can strongly depend on the composition and the ion species. Most crucial in phase separation is then the difference in the solvation free energy between the two phases, which is the origin of the Galvani potential difference known in electrochemist...

3He crystals start to show facets on their surface only at about 100 mK, well below the roughening transition temperature. To understand the reason for that, we have performed the first quantitative investigation on the growth dynamics of the basic (110) facet at 60-110 mK. The obtained values of the step free energy suggest an extremely weak coupling of the solid-liquid interface to the crysta...