Studies on polymer materials used in ophthalmological surgery as intraocular implants are presented in this paper. The material under investigation were brand new lenses provided by Alcon. The first lens, model SA60AT, was the basis structure, whereas the other one, model SN60AT, was a structure with an added modification in the form of a blue light chromophore. Results obtained with the use of the positron annihilation lifetime spectroscopy, as well as UV-vis-NIR methods, showed that the structure modified by the chromophore becomes more packed, while the results obtained by means of the UV-vis-NIR methods showed that the modification restricts the blue light transmission.
The free volume holes and light transmission of hydrogel and silicone-hydrogel polymer contact lenses were investigated. As the material, the Proclear family (omafilcon A) of hydrogel contact lenses and the Biofinity family (comfilcon A) of silicone-hydrogel contact lenses were used. Positron annihilation lifetime spectroscopy was used to characterize geometrical sizes and fractions of the free volume holes in the investigated samples. There was a clear difference in the size of free volume holes and the fractional free volume between silicone-hydrogel and hydrogel polymer contact lenses. These changes are shown by a thorough analysis of the long-lived component of lifetime of ortho-positronium. At the same time, UV-vis-NIR in the spectral range 200-1000 nm studies were performed on the same samples of contact lenses spectrometry.
The studies of the photoinduced second harmonic generation were performed for the Ag-loaded poriferous TiO2 microtablets deposited on an ITO substrate. The poriferous TiO2 microtablets on a pre-cleaned ITO substrate (Kaivo, China, sheet resistance of ca. 10 Ω/square) were prepared by simply immersing the ITO substrate vertically into the growth solution that contains 5 ml of 0.5 M (NH4)2TiF6 (Sigma-Aldrich) and 5 ml of 1.0 M H3BO3 (R.M. Chemicals) for 15 h at room temperature. The samples were obtained from the growth solution with concentration of 0.4, 0.5 and 0.6 M. We have found that maximal second harmonic generation signal was achieved for the samples with concentration 0.5 M.
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