Complex electrical conductivity measurements of a KTB amphibolite sample at elevated temperatures

dc.contributor.author	Σάλτας, Βασίλης	el
dc.contributor.author	Χατζηστάμου, Β.	el
dc.contributor.author	Πεντάρη, Δέσποινα	el
dc.contributor.author	Πάρη, Ελεονώρα	el
dc.contributor.author	Τριάντης, Δήμος Α.	el
dc.date.accessioned	2015-05-16T09:54:23Z
dc.date.available	2015-05-16T09:54:23Z
dc.date.issued	2015-05-16
dc.identifier.uri	http://hdl.handle.net/11400/10501
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://www.elsevier.com/	en
dc.subject	Insulators
dc.subject	Electrical characterisation
dc.subject	Fluorescence X-ray analysis
dc.subject	electrical conductivity
dc.subject	Μονωτές
dc.subject	Ηλεκτρικός χαρακτηρισμός
dc.subject	Ανάλυση φθορισμού ακτίνων Χ
dc.subject	Ηλεκτρική αγωγιμότητα
dc.title	Complex electrical conductivity measurements of a KTB amphibolite sample at elevated temperatures	en
heal.type	journalArticle
heal.classification	Technology
heal.classification	Electrical engineering
heal.classification	Τεχνολογία
heal.classification	Ηλεκτρολογία Μηχανολογία
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh85133147
heal.classificationURI	http://zbw.eu/stw/descriptor/18426-4
heal.classificationURI	N/A-Τεχνολογία
heal.classificationURI	N/A-Ηλεκτρολογία Μηχανολογία
heal.keywordURI	http://lod.nal.usda.gov/28491
heal.contributorName	Φυτίλης, Ιωάννης	el
heal.contributorName	Βαλλιανάτος, Φίλιππος	el
heal.identifier.secondary	DOI: 10.1016/j.matchemphys.2013.01.016
heal.language	en
heal.access	campus
heal.publicationDate	2013-04-15
heal.bibliographicCitation	SALTAS, V., CHATZISTAMOU, V., PENTARI, D., PARIS, E., TRIANTIS, D.A., et al. (2013). Complex electrical conductivity measurements of a KTB amphibolite sample at elevated temperatures. Materials Chemistry and Physics. [Online] 139 (1). p. 169-175. Available from: http://www.elsevier.com/[Accessed 13/02/2013]	en
heal.abstract	In the present work, complex electrical conductivity measurements in the frequency range of 10 mHz-1 MHz and at elevated temperatures (423 K-1373 K) were carried out in amphibolite sample, originating from the KTB drilling. Impedance Cole-Cole plots were used to discriminate the contributions of grain interior, grain boundaries and electrode polarization effects to the measured conductivity spectra. At frequencies above 10 Hz where the electrode effects are negligible, ac-conductivity exhibits frequency dispersion according to a two-term power law behaviour, in most cases of the isothermal spectra. A conductivity relaxation step is observed during heating of the sample up to 773 K, which is attributed to strongly bound water, either in the form of hydroxyls in the crystal lattice of grains, or in the form of molecules trapped between the grain boundaries. The hysteresis plot of dc-conductivity shows an anomalous behaviour at around 1000 K during the heating procedure, due to the dehydroxylation of the sample. The electric modulus M* representation provides additional information over the low temperature range and the conductivity relaxation times were estimated for a limited temperature range. Thermal activation energies of Arrhenius type vary from 0.58 eV up to 1.50 eV, and they are ascribed to proton conduction at low temperature and hopping conduction of small polarons at higher temperatures.	en
heal.publisher	Elsevier	en
heal.journalName	Materials Chemistry and Physics	en
heal.journalType	peer-reviewed
heal.fullTextAvailability	true