Publications by authors named "J Filipecki"
This work is the first one that provides not only evidence for the existence of free volumes in the human stratum corneum but also focuses on comparing these experimental data, obtained through the unique positron annihilation lifetime spectroscopy (PALS) method, with theoretical values published in earlier works. The mean free volume of 0.269 nm was slightly lower than the theoretical value of 0.
View Article and Find Full Text PDFSpectroscopic characterization of calcium phosphate precipitated under human eye conditions: An in vitro study.
Spectrochim Acta A Mol Biomol Spectrosc
September 2023
Article Synopsis
- Calcification in intraocular lenses, caused by calcium phosphate mineralization, lacks a clear understanding of its mechanisms despite extensive research.
- To investigate this phenomenon, the study replicated conditions similar to the human eye, using techniques like SEM/EDS and infrared spectroscopy to analyze calcium phosphate formation.
- Findings revealed the creation of unstable white spherical precipitates with a calcium to phosphorus ratio close to hydroxyapatite, alongside specific chemical structures that indicate hydration of calcium phosphates, informing future research on intraocular lenses.
In this article, we present research on the influence of erbium ions on the structure and magneto-optical properties of 70TeO-5XO-10PO-10ZnO-5PbF (X = Pb, Bi, Ti) tellurite glass systems. Structural changes occurring in the glasses during doping with erbium ions were investigated using positron annihilation lifetime spectroscopy (PALS) and Raman spectroscopy. The X-ray diffraction (XRD) method was used to confirm the amorphous structure of the investigated samples.
View Article and Find Full Text PDFThe aim of the present work was to investigate an influence of W addition on the phase constitution, microstructure and magnetic properties of the PrFeWB (where: x = 2, 4, 6, 8) alloy ribbons. Ribbons were obtained using the melt-spinning technique under low pressure of Ar. The as-cast samples were fully amorphous and revealed soft magnetic properties.
View Article and Find Full Text PDFBackground: The effects of external factors such as X-ray irradiation on the structure and physical properties of contact lenses are very important for both the patients using contact lenses and medical personnel.
Objectives: The aim of the study was to investigate the effect of X-rays on the structure of Narafilcon A silicone-hydrogel contact lenses.
Material And Methods: In order to study the structural changes caused by X-rays in Narafilcon A polymer contact lenses, the following spectroscopy methods were used: positron annihilation lifetime spectroscopy (PALS), Fourier transform middle infrared spectroscopy (FTIR) and Raman spectroscopy (RS).