Search results for "XRD"
showing 10 items of 76 documents
Synthesis of Eu2+ and Dy3+ Doped Strontium Aluminates and their Properties
2017
Financial support to this project was provided by National Research Programme (IMIS2).
Determination of the crystallinity of TiO2 photocatalysts
2018
Abstract This study reports a new simple method to determine the crystallinity of anatase and rutile TiO2 photocatalysts. The crystallinity degree of various anatase and rutile samples was estimated by XRD analysis from the ratio among the full width at half maximum intensities of the main diffraction peaks of anatase or rutile and the (111) peak of CaF2 as internal standard. The photocatalytic activity of selected powders was tested employing the photodegradation of 4-nitrophenol in aqueous solution as probe reaction. The results showed that the photoactivity of the investigated samples increased with increasing crystallinity and crystallite size.
Ethnoarchaeometric Study of the Traditional Cooking Ware Production Centre of Pabillonis (Sardinia): Investigating Raw Materials and Final Products
2010
Ethnoarchaeometry can be used to test assumptions in ceramic provenance studies. Within the Late Roman Cooking Wares (LRCW’s) commercialised in the Western Mediterranean some fabrics such as Fabrics 1.2, 1.6/1.7 and 1.9 (Fulford and Peacock, 1984) have been proposed to have a Sardinian origin. This motivated a specific project to explore the nature of cooking pottery on the island and the raw clays as well as the production technologies that have been used traditionally for their manufacture. In this paper, the traditional cooking pottery making in Pabillonis (Oristano province) was studied. First, a field survey in the area of Pabillonis was undertaken in order to locate the raw materials …
Historical Building Dating: The Multidisciplinary Study of the Convento de São Francisco (Coimbra, Portugal)
2012
ZnxCd1-xO polikristālisko plāno kārtiņu iegūšana un īpašības
2015
Cinka oksīdu, kadmija oksīdu un to cietos šķīdumus mēģina plašāk pielietot elektronikā, pateicoties to fizikālajam īpašībām. Uz to bāzes ražo dažādas heterostruktūras un heteropārejas, kuras ir galvenās sastāvdaļas starojuma avotos un detektoros. Šajā maģistra darbā ir apkopota informācija par cinka oksīda, kadmija oksīda un to cieto šķīdumu kārtiņu iegūšanas metodēm, aprakstītas šo materiālu galvenās īpašības. Darba praktiskajā daļā parādītas jaunās ekstrakcijas-pirolītiskās metodes iespējas ZnO-CdO plāno kārtiņu iegūšanai uz stikla un kvarca pamatnēm. Paraugu raksturošanai izmanto rentgenstaru difrakcijas un skenējošo elektronu mikroskopiju. Daļai kārtiņu nosaka arī biezumu. Iegūtās kārti…
Oxidative dehydrogenation of ethane over NiO–CeO2 mixed oxides catalysts
2012
[EN] In this paper we present the synthesis, characterization and catalytic behaviour in the oxidative dehydrogenation of ethane of NiO-CeO2 mixed oxides. The addition of cerium oxide to NiO strongly modifies its catalytic performance, although the changes in the catalytic behaviour depend on the catalyst composition. The incorporation of low amounts of cerium oxide to NiO multiplies the productivity to ethylene in the oxidative dehydrogenation of ethane by a factor of ca. 7, which is the result of an increase in both catalytic activity and selectivity to ethylene. The enhanced activity has been related to the remarkable increase of the surface area of catalyst and the low crystal sizes of …
Premature aging in bone of fish from a highly polluted marine area
2015
Fish species have attracted considerable interest in studies assessing biological responses to environmental contaminants. In this study, the attention has been focussed on fishbone of selected fish species from a highly polluted marine area, Augusta Bay (Italy, Central Mediterranean) to evaluate if toxicant elements had an effect on the mineralogical structure of bones, although macroscopic deformations were not evident. In particular, an attempt was made to evaluate if bone mineral features, such as crystallinity, mineral maturity and carbonate/phosphate mineral content, determined by XR-Diffraction and FT-IR Spectroscopy, suffered negative effects due to trace element levels in fishbone,…
Colour Specification of Terracotta Calatina Specimens
2012
Degradation study of XVIII century graffiti on the walls of Chiaramonte Palace (Palermo, Italy)
2010
A systematic investigation of the original materials and the degradation phenomena induced by soluble salts on the wall matrix and on the graffiti of the Inquisition jails of Chiaramonte Palace in Palermo (Italy) was carried out. Built in the XIV century, Chiaramonte Palace was used as Inquisition court during the XV–XVI centuries. The ancient graffiti, recently discovered, represent a unique historical witness of the prisoners that lived during that terrible period. In order to study the nature, the amount and the distribution of the salts in the masonry, stone materials sampled at different depth from the wall matrix and saline efflorescences were analysed. Different physical techniques w…
Il Progetto ATENA: Applicazione di metodologie innovative per la conservazione di manufatti metallici e ceramici da scavo archeologico e per il recup…
2007
Qui di seguito viene illustrato il progetto scientifico ATENA, svolto presso l'Istituto per lo Studio dei Materiali Nanostrutturati (ISMN) del Consiglio Nazionale delle Ricerche (CNR) e co-finanziato dal MIUR con Decreto Direttoriale 9-10-2002, n. 1105/2002. Il progetto si propone di applicare avanzate tecniche diagnostiche strumentali al fine di acquisire la dettagliata conoscenza microchimica e microstrutturale di manufatti metallici e ceramici antichi, di definirne il meccanismo di alterazione e/o degrado e di progettare, sintetizzare e validare opportuni prodotti e formulazioni per il restauro conservativo di tali manufatti. Le conoscenze acquisite sono utilizzabili anche per il recuper…