Identifying the mechanisms that control formation of compaction bands is high interest in reservoir mechanics since these structures may drastically affect performance geosystems operations. Considering difficulty to identify carbonate samples tested laboratory, Digital Volume Correlation technique applied here and proves be a relevant method. X-Ray Computed Tomography (XRCT) images Saint-Maxim...

PURPOSE The purpose of this study was to compare the surface dose of 7-field IMRT (7 F-IMRT), tangential beam IMRT (TB-IMRT), and tangential beam 3D-CRT (3D-CRT) of breast cancer patients receiving adjuvant radiotherapy by means of in vivo GafChromic film dosimetry. MATERIAL AND METHODS Breast cancer patients receiving adjuvant radiotherapy of the whole breast or the chest wall were eligible ...

The absorption spectra of the GAFCHROMIC XR type R radiochromic film measured with reflectance spectroscopy have been investigated in order to analyze the dosimetry characteristics of the film. Like the XR type T film, this film features two peaks in its absorption spectrum, approximately at 676 and 618 nm, whose intensities increase with increasing absorbed dose. When the main absorption peak ...

PURPOSE The purpose of this study is to evaluate the radiation dose in patients undergoing liver angiographic procedure and verify the usefulness of different dose measurements to prevent deterministic effects. Gafchromic film, MicroMOSFET data and DIAMENTOR device of the X-ray system were used to characterize the examined interventional radiology (IR) procedure. MATERIALS AND METHODS A liver...

Some of the lowest voltages used in radiotherapy are termed Grenz and superficial X-rays of ~ 20 and ~ 100 kVp, respectively. Dosimetrically, the surface doses from these beams are calculated with the use of a free in-air air kerma measurement combined with a backscatter factor and the appropriate ratio of mass energy absorption coefficients from the measurement material to water. Alternative t...

Measurement of the lateral profile of the dose distribution across a narrow x-ray microbeam requires a dosimeter with a micron resolution. We investigated the use of a MOSFET dosimeter in an "edge-on" orientation with the gate insulating oxide layer parallel to the direction of the beam. We compared results using this technique to Gafchromic film measurements of a 200 micrometer wide planar x-r...

Abstract Viscoelastic strain rate-dependent behaviour of coal is critical in several subsurface engineering applications especially seams gas production. Such rate dependency controlled by the interaction between bulk and sorption (a sorbing gas) or pressure non-sorbing gas). Despite research conducted to date, effect (non-sorbing) on viscous sediments particular remains unexplored. We, therefo...

Abstract The hydromechanical behaviour of fractured coal is a complex function interaction between bulk and fracture deformation driven by fluid pressure external stress. Despite the research studies conducted to date, combined effect mineral content structure on sorptive remains unexplored. To study this effect, we performed series X-ray computed tomography (XRCT) imaging range specimens with ...

background: small photon fields are increasingly used in modern radiotherapy especially in intensity modulated radiation therapy (imrt) and stereotactic radiosurgery (srs) treatments. accurate beam profile and central axis depth doses measurements of such beams are complicated due to the electron disequilibrium. hence the ebt2 (external beam therapy) gafchromic film was used for dosimetry of sm...

AIM The purpose of the study was to examine the energy dependence of Gafchromic EBT radiochromic dosimetry films, in order to assess their potential use in intensity-modulated radiotherapy (IMRT) verifications. MATERIALS AND METHODS The film samples were irradiated with doses from 0.1 to 12 Gy using photon beams from the energy range 1.25 MeV to 25 MV and the film response was measured using ...