Phenol compounds as new materials for electron spin resonance dosimetry in radiotherapy

The effect of particle size on pigments colour

Characterization of phenolic pellets for ESR dosimetry in photon beam radiotherapy

This work deals with the dosimetric features of a particular phenolic compound (IRGANOX 1076 ® ) for dosimetry of clinical photon beams by using electron spin resonance (ESR) spectroscopy. After the optimization of the ESR readout parameters (namely modulation amplitude and microwave power) to maximise the signal without excessive spectrum distortions, basic dosimetric properties of laboratory-made phenolic dosimeters in pellet form, such as reproducibility, dose–response, sensitivity, linearity and dose rate dependence were investigated. The dosimeters were tested by measuring the depth dose profile of a 6 MV photon beam. A satisfactory intra-batch reproducibility of the ESR signal of the …

DIFFERENT APPROACHES TO DATE BRICKS FROM HISTORICAL BUILDINGS

Abstract The application of Thermally (TL) and Optically (OSL) Stimulated Luminescence on bricks used as building material has allowed solving an chronological issue in the field of historical building dating. The possibility to use one or more methodologies of dating is closely related to the luminescent and granulometric characteristics of the sample. Using some brick samples collected in the church of Sain Seurin in Bordeaux (France), this paper discusses the implications and the possibility to use different approaches and techniques for dating. With this aim luminescence measurements were performed on both polymineral fine grain and quartz inclusion phases extracted from each brick. For…

"Historical pigments characterisation by quantitative X-ray fluorescence"

Abstract Most of the historical paints are mainly constituted by inorganic pigments, either pure or mixed, spread on the surfaces using different binding agents. The knowledge of the exact amount of different constituents of the paint, as well as of the mixing and pictorial techniques, is crucial for a careful program of conservation of polychrome works. Moreover, since the availability of these pigments has been changing through the centuries, their identification and chemical characterisation is useful to acquire or deepen information about the artist and his/her work. This information can also be useful for authentication purposes through relative dating because the identification of one…

Misure di colore su film radiocromici: nuove frontiere per la dosimetria

Middle-Late Pleistocene marine terraces and fault activity in the Sant’Agata di Militello coastal area (north-eastern Sicily)

Abstract The coastal sector of Sant’Agata di Militello (north-eastern Sicily) is characterized by a flight of raised Middle-Upper Pleistocene marine terraces occurring at different heights with respect to present sea level. In particular, the geomorphological survey and the analysis of stereo-pairs of aerial photographs allowed to recognize at least five main orders of well preserved Quaternary surfaces and relative deposits mostly located at the hanging wall and at the footwall of the Pleistocene northwest-dipping Capo d’Orlando normal fault, which controlled the geomorphological evolution of the coastal area. The marine terraces show an overall good morphological continuity and are formed…

Historical mortars dating from OSL signal of fine grain fraction enriched in quartz

Abstract In the last years the mortar dating through Optically Stimulated Luminescence (OSL) techniques has become a viable support for chronological estimations (date of construction or restoration episodes) of historical buildings. However, the dating of mortar has still open issues mainly regarding the assessment of the bleaching degree of quartz, the analysis of the OSL processes for this type of samples and the need to do appropriate tests for the most correct evaluation of the equivalent dose. This paper discusses the results obtained by OSL dating (blue diode stimulation) on the polymineral fine grain phase, enriched in quartz, extracted from lime mortar samples collected from differ…

Specificazione del colore di provini di terracotta calatina

La classificazione della ceramica da scavo prevede l’attribuzione di una tinta ad ogni coccio rinvenuto, ma l’uso regolare di un sistema per la specificazione del colore è ad oggi un problema aperto. Gli archeologi prediligono le Munsell Soil Color Chart ma la classificazione che ne deriva, oltre che della soggettività insita in tale sistema, soffre di un’ulteriore variabile legata alla difficile realizzazione sui siti di scavo delle condizioni di illuminazione controllata necessarie per il confronto tra le tavole e i cocci. Il colore della ceramica è inoltre fortemente dipendente dalle condizioni di cottura per cui anche manufatti realizzati con le stesse materie prime possono presentare e…

Cutting efficiency of heat-treated nickel-titanium single-file systems at different incidence angles.

Cutting efficiency of Reciproc R25 (REC) and Reciproc blue R25 (REB) at different inclinations was evaluated. Sixty new files were tested at 90°, 70° and 45° of inclination in relation to the sample (n = 10), using a customised machine. All files were activated in reciprocation against standardised gypsum blocks for 120 s. Cutting efficiency was determined by measuring the block weight loss with an analytical balance and measuring the length of the block surface cut using a digital calliper. Data were statistically analysed (two-way ANOVA, Bonferroni t-test) with the significance level set at P < 0.05. There was no difference for REC among the tested angles. REB had no statistical differenc…

Nuclear magnetic resonance relaxometry and imaging for dosimetry with agarose Fricke gel