Παρασκευή, χαρακτηρισμός και μελέτη της ιοντικής αγωγιμότητας υποκατεστημένων περοβσκιτών της γενικής μορφής LaxA(1-x)FeO3 A=Ba,Sr x=0..1

100 σ.Έγινε παρασκευή των περοβσκιτών με την μέθοδο των άμορφων κιτρικών συμπλόκων, κρυσταλλογραφικός έλεγχος τους για τον καθορισμό της μονοφασικότητας τους, μέτρηση του συντελεστή θερμικής διαστολής, έλεγχος με ηλεκτρονική μικροσκοπία, μέτρηση της ιοντικής τους αγωγιμότητας και τέλος αναγωγή των αποτελεσμάτων σε διαπερατότητα οξυγόνου.The perovskites were synthesized by the amorphous citrate route, there were analyzed by XRD in order to determine if they were single phased. Thermal expansion coefficient analysis took plase, among with SEM. Ionic conductivity of the perovskites was measured and finally those measurements were translated to oxygen permeation.Βασίλειος Δ. Σιαπέρα

A Promising Technological Approach to Improve Indoor Air Quality

Indoor Air quality (IAQ) in private or public environments is progressively recognized as a critical issue for human health. For that purpose the poor IAQ needs to be mitigated and immediate drastic measures must be taken. In environmental science and especially in advanced oxidation processes and technologies (AOPs-AOTs), photocatalysis has gained considerable interest among scientists as a tool for IAQ improvement. In the current study an innovative paint material was developed which exhibits intense photocatalytic activity under direct and diffused visible light for the degradation of air pollutants, suitable for indoor use. A laboratory and a real scale study were performed using the above innovative photo-paint. The lab test was performed in a special design photo-reactor while the real scale in a military’s medical building. Nitrogen Oxide (NO) and Toluene concentration was monitored between “reference” rooms (without photo paint) and “green” rooms (with photo-paint) in order to estimate the photocatalytic efficiency of the photo-paint to degrade the above pollutants. Results of the study showed a decrease up to 60% and 16% for NO and toluene respectively under lab scale tests while an improvement of air quality up to 19% and 5% under real world conditions was achieved