Technological Educational Institute of Western Macedonia

About: Technological Educational Institute of Western Macedonia is a based out in . It is known for research contribution in the topics: Symplectic geometry & Numerical integration. The organization has 291 authors who have published 522 publications receiving 7682 citations. The organization is also known as: TEI of West Macedonia & TEI of Western Macedonia.

Trigonometrically fitted and exponentially fitted symplectic methods for the numerical integration of the Schrödinger equation

Abstract: The solution of the one-dimensional time-independent Schrodinger equation is considered by exponentially fitted symplectic integrators. The Schrodinger equation is first transformed into a Hamiltonian canonical equation. Numerical results are obtained for the one-dimensional harmonic oscillator and the doubly anharmonic oscillator.

Polymer-Silica nanoparticles composite films as protective coatings for stone-based monuments

Abstract: The decrease of surface energy of mineral substrates similar to those used in many stone monuments of cultural heritage by the application of protective polymer coatings along with the simultaneous increase of their surface roughness can increase their ability to repel water substantially. In this work, the effect of artificially induced roughness on the water repellency of mineral substrates coated with protective polymer films was investigated. Natural marble samples or home made calcium carbonate blocks were tried as the mineral substrates. The roughness increase was achieved by mineral chemical etching or by creation of nanoscale binary composition film on the substrate surface. PMMA and PFPE were the polymers used, while different-sized silica nanoparticles were employed for the production of the nanocomposite films. Examination of the coated and uncoated surfaces with profilometry and AFM and measurements of water contact angles reveal a pronounced effect of the surface roughness on water repellency. Especially in the case of nanocomposite coatings, the surfaces become super-hydrophobic. This result indicates that the nanoscale binary composition film scheme, which is characterized by its simplicity and low cost, is a suitable candidate for the water protection of stone-based monuments on large scale.