Since ozone is highly corrosive, it can substantially affect the mechanical and chemical properties of the materials; consequently, it could affect the applicability of those materials in medical applications. The effect of ozone sterilization on the chemical and mechanical properties of additively manufactured specimens of biocompatible poly(methyl-methacrylate) was observed. FDM 3D-printed specimens of biocompatible PMMA in groups of five were exposed to high concentrations of ozone generated by corona discharge for different durations and at different ozone concentrations inside an enclosed chamber with embedded and calibrated ozone, temperature, and humidity sensors. A novel approach using laser-induced fluorescence (LIF) and spark-discharge optical emission spectrometry (SD-OES) was used to determine an eventual change in the chemical composition of specimens. Mechanical properties were determined by testing the tensile strength and Young’s modulus. A calibrated digital microscope was used to observe the eventual degradation of material on the surface of the specimens. SD-OES and LIF analysis results do not show any detectable sterilization-caused chemical degradation, and no substantial difference in mechanical properties was detected. There was no detectable surface degradation observed under the digital microscope. The results obtained suggest that ozone sterilization appears to be a suitable technique for sterilizing PMMA medical devices.

A new method has been proposed for detecting the potential adulteration of extra virgin olive oil with processed sunflower oil. This method is based on analysing the laser-induced fluorescence (LIF) spectra of samples. The technique involves measuring the intensity ratio of three specific fluorescence peaks within the 650–750 nm region of the spectra, which are attributed to chlorophyll derivatives. The samples are excited with a 460 nm blue laser in an offset configuration. The results obtained indicate that the relative intensity ratio of these characteristic chlorophyll peaks is consistently correlated with the percentage of oil adulteration. A parameter named the chlorophyll relative intensity (CRI) number has been introduced, which is based on the relative intensity ratios of the chlorophyll peaks in the LIF spectra of the extra virgin olive oil sample. The CRI function demonstrates a linear relationship with the adulteration percentage up to 80%, with a high regression coefficient ( R ² ) value of 0.9984. This method can be applied accurately when the original fluorescence spectra of unadulterated extra virgin olive oil are known, and it can provide valuable information about the source of unknown oil samples.

While any instrumental elemental analysis is often thought of as an expensive and complicated technique requiring large investments, we present a design of a high-temperature plasma spectrometer, a Spark Discharge Optical Emission Spectroscopy (SD-OE...

The topology optimization has been presented in the example of a gyroid cantilever beam with a rectangular cross-section by using the software nTopology. The accuracy of the numerical model was checked by analytical solution, and by measuring strain...

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