SEM EDS

Για τις  ανάγκες της κατανόησης των υλικών κατασκευής των ρωμαϊκών λουτρών Δερβενίου Κορινθίας, λήφθησαν συνολικά 31 δείγματα από 21  σημεία ενδιαφέροντος από 9 διαφορετικούς χώρους του κτιρίου. Αυτά περιελάμβαναν  δείγματα συνδετικού κονιάματος τοιχοποιίας, κονιαμάτων επιχρίσματος τοίχων,  επιτοίχιου λίθου (ορθομαρμάρωση), χυτού κονιάματος (opus caementicium), επιδαπέδιων κεραμικών αγωγών, λίθινες καλυπτρίδες επιδαπέδιων αγωγών, κεραμικού tubuli,  κεραμικού υλικού και συνδετικού κονιάματος από στυλίσκους (pilae) των υπόκαυστων, επιδαπέδιου κονιάματος, λίθινης επιδαπέδιας πλάκας και δείγματα από τη στρωματογραφία του μοναδικού ψηφιδωτού του χώρου. Μετά την επιτόπια φωτογραφική τεκμηρίωση και κωδικοποίηση των σημείων δειγματοληψίας, τα δείγματα φωτογραφήθηκαν και μελετήθηκαν με οπτική μικροσκοπία. Στη συνέχεια διενεργήθηκαν αναλύσεις με Φθορισμομετρία Ακτίνων-Χ (XRF) για το χημικό χαρακτηρισμό τους, Περιθλασιμετρία Ακτίνων-Χ (XRD) για την ορυκτολογική τους μελέτη, και Ηλεκτρονικό Μικροσκόπιο Σάρωσης με Φασματόμετρο Ενεργειακής Διασποράς Ακτίνων Χ (SEΜ-EDS) για τη μελέτη της μικροτοπογραφίας τους. Από τη μελέτη προέκυψαν στοιχεία για τη στρωματογραφία των κονιαμάτων επιχρίσματος των εσωτερικών και εξωτερικών τοίχων, τη στρωματογραφία και τεχνολογία κατασκευής του ψηφιδωτού, την τεχνολογία κατασκευής των συνδετικών κονιαμάτων και των χυτών κονιαμάτων, και τη σύσταση των κεραμικών οικοδομικών υλικών και των λίθων που απαντώνται στο μνημείο. Τα αποτελέσματα συμβάλλουν στη μεγαλύτερη κατανόηση της τεχνολογίας κατασκευής των δημόσιων λουτρών της ύστερης ρωμαϊκής περιόδου στην Πελοποννήσο, ενώ θα συμβάλλουν καθοριστικά στις προγραμματισμένες επεμβάσεις καθαρισμού, στερέωσης και συμπλήρωσης για την in situ  αποκατάσταση και έκθεση του μνημείου.

For the purposes of understanding the construction materials of the Derveni Roman Baths in Corinthia, Greece, 31 samples were collected from 21 sampling points in 9 different rooms of the archaeological site. These included masonry mortars, wall plastering, wall cladding, cast mortars (opus caementicium), ceramic floor pipes, covers of floor pipes, ceramic tubuli, ceramic material and binding mortars from the pilae of the hypocausts, floor mortar, stone floor tiles, and samples of the stratigraphy of the only mosaic of the site. After in situ photographic documentation and coding of the samples, the latter were photographed and examined by optical microscopy. Other techniques employed were X-ray Fluorescence (XRF) for chemical classification, X-ray Diffraction (XRD) for the mineralogical study, and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) for the study of their microtopography. The study revealed information on the stratigraphy of the plaster coatings of the interior and exterior walls, the stratigraphy and construction technique of the mosaic, the manufacture technique of the cast mortars and the binding mortars, and the composition of ceramic building materials and stones found in the monument. The results contribute to the greater understanding of the construction technology of public baths of the late Roman period in the Peloponnese, and will contribute to the decision making regarding the scheduled cleaning, consolidation and filling for the in situ conservation and exhibition of the monument.

Nanocrystalline ZrO2 and TiO2 (n-ZrO2, n-TiO2), synthesized in a microwave plasma, have been investigated by X-ray and electron diffraction and by perturbed angular correlation (PAC) measurements of the nuclear electric quadrupole interaction (QI) of the probe nucleus 181Ta residing on the cation site. The microwave synthesis produces zirconia in the cubic/tetragonal phase, titania in the anatase structure. Grain growth and phase transformations have been studied in bare and Al2O3-coated zirconia particles. Coating the nanoparticles with an amorphous Al2O3 layer obstructs grain growth and may suppress the monoclinic phase.

The effect of a high frequency alternating magnetic field on HeLa tumour cells incubated with ferromagnetic nanoparticles of manganese oxide perovskite La0.56(SrCa)0.22MnO3 have been studied. The particles were subjected to a size selection process and coated with silica to improve their biocompatibility. The control assays made with HeLa tumour cells showed that cell survival and growth rate were not affected by the particle internalization in cells, or by the electromagnetic field on cells without nanoparticles. However, the application of an alternating electromagnetic field to cells incubated with this silica coated manganese oxide induced a significant cellular damage that finally lead to cell death by an apoptotic mechanism. Cell death is triggered even thought the temperature increase in the cell culture during the hyperthermia treatment is lower than 0.5 C.

In the past few years ferromagnetic-like behavior has been reported in metal gold nanoparticles coated with diverse organic surfactants. In this work we report on the effect of thermal annealing on the ferromagnetic-like behavior of oleic acid and oleylamine coated gold nanoparticles of about 7 nm size. The magnetic moment of the “as prepared” sample is about 3×10−2 emu/g and the coercive field is 200 Oe at 10 kOe and 5 K, after the annealing the behavior changes from ferromagnetic-like to paramagnetic and the magnetization at 10 kOe decreases at a factor of 10. These results are compared with those obtained for oleylamine coated gold nanoparticles, which are diamagnetic at room temperature.

The effect of a high frequency alternating magnetic field on HeLa tumour cells incubated with ferromagnetic nanoparticles of manganese oxide perovskite La0.56(SrCa)0.22MnO3 have been studied. The particles were subjected to a size selection process and coated with silica to improve their biocompatibility. The control assays made with HeLa tumour cells showed that cell survival and growth rate were not affected by the particle internalization in cells, or by the electromagnetic field on cells without nanoparticles. However, the application of an alternating electromagnetic field to cells incubated with this silica coated manganese oxide induced a significant cellular damage that finally lead to cell death by an apoptotic mechanism. Cell death is triggered even thought the temperature increase in the cell culture during the hyperthermia treatment is lower than 0.5 C.