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Experimental study of the rigidity and transparency to ionizing radiation of composite materials used in the enclosure under pressure of the Micromegas detector 1 3 4 5 6 7 8 9 10 11 1 3 14 15 16 17 1[.]
RINP 586 No of Pages 6, Model 5G 23 February 2017 Results in Physics xxx (2017) xxx–xxx Contents lists available at ScienceDirect Results in Physics journal homepage: www.journals.elsevier.com/results-in-physics Experimental study of the rigidity and transparency to ionizing radiation of composite materials used in the enclosure under pressure of the Micromegas detector Imen Harbaoui a,⇑, Hatem Besbes b, Moez Chafra a 10 11 14 15 16 17 18 19 20 21 22 23 24 25 26 27 a b Applied Mechanics and Systems Research Laboratory, Tunisia Polytechnic School, University of Carthage, La Marsa, Tunisia King Abdul-Aziz University, Faculty of Sciences, Physics Department, Jeddah, Saudi Arabia a r t i c l e i n f o Article history: Received October 2016 Received in revised form 14 February 2017 Accepted 15 February 2017 Available online xxxx Keywords: Nuclear imaging Micromegas detector Composites Robustness Transparency to gamma radiations Synthetic fibers Vegetable fibers a b s t r a c t Innovation in the field of nuclear imaging is necessarily followed by a radical change in the detection principle The gas detector Micromegas (Mesh Micro Structure Gaseous) could be an interesting option, thanks to the stability and robustness of such a detector Thus, it was necessary to study the implementation of the detector enclosure in composite materials The focus of the present study was the robustness and gamma rays transparency of a set of composites The studied composites were reinforced with vegetable fibers (alfa), and synthetic fibers The mechanical properties of all composites specimen were evaluated by three-point bending test, whereas, gamma ray transparency was evaluated by the exposition of composites specimen to a mono-energetic gamma ray beam emitted by a Technetium 99-m source Findings revealed that the biocomposite materials using alfa fiber and Polymethyl Methacrylate matrix are very promising as long as they present good robustness and high gamma ray transparency in diagnostic range Ó 2017 Published by Elsevier B.V This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/) 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Introduction 45 Actually nuclear imaging (scintigraphy and Positron emission tomography (PET)) is essentially based on scintigraphic detection For example for scintigraphy, since the first gamma camera [1,2] was designed, by Anger, in 1954 [2], there has been no radical changes in the detection process However many manufacturers tried to improve the performance of gamma camera by: smoothing collimators to increase detection efficiency [3], developing systems of rectification of physical phenomena including reconstruction process (correction of mitigation, loss of spatial resolution at depth [4,5]), renovation of algorithms granting the reduction of acquisition time and/or injected activities [6,7] Therefore, compared to the evolution of the image construction and processing software, the obtained quality evolution is very weak To obtain an in-depth evolution in parameters qualities in nuclear imaging that satisfies the actually clinical needs, it is indispensable to change the detection principal Our approach consists in adopting a new imaging system that uses a new sophisticated gas detector called Micromegas (Mesh micro structure gaseous) 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 ⇑ Corresponding author E-mail addresses: imene.harbaoui8@gmail.com (I Harbaoui), chafra_moez@ yahoo.fr (M Chafra) [8] In fact, this particular type of detectors presents several advantages as low time resolution (