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Bajuri F, Bradley D, Mustafa S, Tamchek N, Ahmad Saad F, Mazlan N, Mohd Noor N. Morphology and thermoluminescence characteristics of customised Ge-doped optical fibre under Am–Be neutron source as a potential to be used for space radiation detector. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Khandaker MU, Nawi SM, Lam S, Bradley D, Sani SA, Faruque M, Yasmin S, Idris AM. Studies of defect states and kinetic parameters of car windscreen for thermoluminescence retrospective dosimetry. Appl Radiat Isot 2022; 186:110271. [DOI: 10.1016/j.apradiso.2022.110271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/27/2022] [Accepted: 05/02/2022] [Indexed: 11/28/2022]
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Alyahyawi A, Dimitriadis A, Nisbet A, Bradley D. GeB flat fibre TL dosimeters for in-vivo measurements in radiosurgery. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2020.108973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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4
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Kandan V, Hassan M, Omar N, Shahar H, Mohamad F, Abdul Karim M, Abdul Sani S, Bradley D, Mohd Noor N. Advanced glow curve analysis of fabricated fibres for various sources of ionizing radiation. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2020.108981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Lam S, Bradley D, Khandaker M. Small-field radiotherapy photon beam output evaluation: Detectors reviewed. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2020.108950] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Lam SE, Noor NM, Bradley DA, Mahmud R, Pawanchek M, Abdul Rashid HA. Small-field output ratio determination using 6 mol% Ge-doped silica fibre dosimeters. Biomed Phys Eng Express 2020; 6. [PMID: 35042836 DOI: 10.1088/2057-1976/abc2a4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 10/19/2020] [Indexed: 11/12/2022]
Abstract
This work investigates the suitability of locally fabricated 6 mol% Ge-doped optical fibres as dosimeters for small-field output ratio measurements. Two fabrications of fibre, cylindrical (CF) and flat (FF) fibres, were used to measure doses in small photon fields, from 4 to 15 mm. The findings were compared to those of commercial Ge-doped fibre (COMM), EBT3 film and an IBA CC01 ionization chamber. Irradiations were carried out using a 6 MV SRS photon beam operating at a dose rate of 1000 cGy min-1, delivering a dose of 16 Gy. To minimise the possibility of the fibres failing to be exposed to the intended dose in small fields, the fibres were accommodated in a custom-made Perspex phantom. For the 4 mm cone the CF and FF measured output ratios were found to be smaller than obtained with EBT3 film by 32% and 13% respectively. Conversely, while for the 6 to 15 mm cone fields the FF output ratios were consistently greater than those obtained using EBT3 film, the CF output ratios differed from those of EBT3 film by at most 3.2%, at 6 mm, otherwise essentially agreeing with EBT3 values at the other field sizes. For the 4 to 7.5 mm cones, all output ratios obtained from Ge-doped optical fibre measurements were greater than those of IBA CC01 ionization chamber. The measured FF and CF output ratios for the 7.5 to 15 mm cones agreed with published MC estimates to within 15% and 13%, respectively. Down to 6 mm cone field, present measurements point to the potential of CF as a small-field dosimeter, its use recommended to be complemented by the use of EBT3 film for small-field dosimetry.
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Affiliation(s)
- S E Lam
- Centre for Biomedical Physics, School of Healthcare and Medical Sciences, Sunway University, 47500 Petaling Jaya, Selangor, Malaysia.,Department of Radiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - N Mohd Noor
- Department of Radiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.,Department of Radiology, Teaching Hospital Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - D A Bradley
- Centre for Biomedical Physics, School of Healthcare and Medical Sciences, Sunway University, 47500 Petaling Jaya, Selangor, Malaysia.,Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - R Mahmud
- Department of Radiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.,Centre for Diagnostic Nuclear Imaging, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - M Pawanchek
- Department of Radiotherapy and Oncology, National Cancer Institute, 62250 W.P. Putrajaya, Malaysia
| | - H A Abdul Rashid
- Faculty of Engineering, Multimedia University, 63100 Cyberjaya, Selangor, Malaysia
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Wahib NB, Abdul Sani SF, Ramli A, Ismail SS, Abdul Jabar MH, Khandaker MU, Daar E, Almugren KS, Alkallas FH, Bradley DA. Natural dead sea salt and retrospective dosimetry. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2020; 59:523-537. [PMID: 32462382 DOI: 10.1007/s00411-020-00846-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 04/29/2020] [Indexed: 06/11/2023]
Abstract
Accidents resulting in widespread dispersal of radioactive materials have given rise to a need for materials that are convenient in allowing individual dose assessment. The present study examines natural Dead Sea salt adopted as a model thermoluminescence dosimetry system. Samples were prepared in two different forms, loose-raw and loose-ground, subsequently exposed to 60Co gamma-rays, delivering doses in the range 2-10 Gy. Key thermoluminescence (TL) properties were examined, including glow curves, dose response, sensitivity, reproducibility and fading. Glow curves shapes were found to be independent of given dose, prominent TL peaks for the raw and ground samples appearing in the temperature ranges 361-385 ºC and 366-401 ºC, respectively. The deconvolution of glow curves has been undertaken using GlowFit, resulting in ten overlapping first-order kinetic glow peaks. For both sample forms, the integrated TL yield displays linearity of response with dose, the loose-raw salt showing some 2.5 × the sensitivity of the ground salt. The samples showed similar degrees of fading, with respective residual signals 28 days post-irradiation of 66% and 62% for the ground and raw forms respectively; conversely, confronted by light-induced fading the respective signal losses were 62% and 80%. The effective atomic number of the Dead Sea salt of 16.3 is comparable to that of TLD-200 (Zeff 16.3), suitable as an environmental radiation monitor in accident situations but requiring careful calibration in the reconstruction of soft tissue dose (soft tissue Zeff 7.2). Sample luminescence studies were carried out via Raman and Photoluminescence spectroscopy as well as X-ray diffraction, ionizing radiation dependent variation in lattice structure being found to influence TL response.
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Affiliation(s)
- Norfadira Binti Wahib
- Department of Physics, University of Malaya, 50603, Kuala Lumpur, Malaysia
- Centre for Biomedical Physics, School of Healthcare and Medical Sciences, Sunway University, 47500, Bandar Sunway, Selangor, Malaysia
| | - S F Abdul Sani
- Department of Physics, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Ain Ramli
- Department of Physics, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S S Ismail
- Department of Physics, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | | | - M U Khandaker
- Department of Physics, University of Malaya, 50603, Kuala Lumpur, Malaysia
- Centre for Biomedical Physics, School of Healthcare and Medical Sciences, Sunway University, 47500, Bandar Sunway, Selangor, Malaysia
| | - E Daar
- Department of Physics, The University of Jordan, Amman, 11942, Jordan
| | - K S Almugren
- Department of Physics, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - F H Alkallas
- Department of Physics, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - D A Bradley
- Centre for Biomedical Physics, School of Healthcare and Medical Sciences, Sunway University, 47500, Bandar Sunway, Selangor, Malaysia
- Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK
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Mat Nawi SN, Abdul Sani SF, Khandaker MU, Ung NM, Almugren KS, Alkallas FH, Bradley DA. Tailored Ge-doped fibres for passive electron radiotherapy dosimetry. PLoS One 2020; 15:e0235053. [PMID: 32673337 PMCID: PMC7365440 DOI: 10.1371/journal.pone.0235053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 06/07/2020] [Indexed: 12/03/2022] Open
Abstract
Study has been made of the thermoluminescence yield of various novel tailor-made silica fibres, 6 and 8 mol % Ge-doped, with four differing outer dimensions, comprised of flat and cylindrical shapes, subjected to electron irradiation. Main thermoluminescence dosimetric characteristics have been investigated, including the glow curve, dose response, energy dependence, minimum detectable dose, effective atomic number, linearity of index and sensitivity of the fibres. The studies have also established the uncertainties involved as well as the stability of response in terms of fading effect, reproducibility and annealing. In addition, dose-rate dependence was accounted for as this has the potential to be a significant factor in radiotherapy applications. The 6 and 8 mol % fibres have been found to provide highly linear dose response within the range 1 to 4 Gy, the smallest size flat fibre, 6 mol% Ge-doped, showing the greatest response by a factor of 1.1 with respect to the highly popular LiF phosphor-based medium TLD100. All of the fibres also showed excellent reproducibility with a standard deviation of < 2% and < 4% for 6 and 8 mol % Ge-doped fibres respectively. For fading evaluation, the smallest 6 mol% Ge-doped dimension flat fibre, i.e., 85 × 270 μm displayed the lowest signal loss within 120 days post-irradiation, at around 26.9% also showing a response superior to that of all of the other fibres. Moreover, all the fibres and TLD-100 chips showed independence with respect to electron irradiation energy and dose-rate. Compared with the 8 mol% Ge-doped optical fibres, the 6 mol% Ge-doped flat optical fibres have been demonstrated to possess more desirable performance features for passive dosimetry, serving as a suitable alternative to TLD-100 for medical irradiation treatment applications.
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Affiliation(s)
- Siti Nurasiah Mat Nawi
- Institute for Health Care Development, Sunway University, PJ, Malaysia
- Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - S. F. Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - M. U. Khandaker
- Institute for Health Care Development, Sunway University, PJ, Malaysia
| | - N. M. Ung
- Clinical Oncology Unit, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - K. S. Almugren
- Department of Physics, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - F. H. Alkallas
- Department of Physics, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - D. A. Bradley
- Institute for Health Care Development, Sunway University, PJ, Malaysia
- Department of Physics, University of Surrey, Guildford, United Kingdom
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Bradley D, Khandaker M, Alanazi A. Irradiated glass and thermoluminescence yield: Dosimetric utility reviewed. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108680] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Thermoluminescence characterization of smartphone screen for retrospective accident dosimetry. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2019.04.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Zakaria Z, Aziz MA, Ishak N, Suppiah S, Bradley D, Noor NM. Advanced thermoluminescence dosimetric characterization of fabricated Ge-Doped optical fibres (FGDOFs) for electron beams dosimetry. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2019.108487] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Rozaila ZS, Khandaker MU, Abdul Sani SF, Sabtu SN, Amin YM, Maah MJ, Bradley DA. Environmental monitoring through use of silica-based TLD. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2017; 37:761-779. [PMID: 28581438 DOI: 10.1088/1361-6498/aa770e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The sensitivity of a novel silica-based fibre-form thermoluminescence dosimeter was tested off-site of a rare-earths processing plant, investigating the potential for obtaining baseline measurements of naturally occurring radioactive materials. The dosimeter, a Ge-doped collapsed photonic crystal fibre (PCFc) co-doped with B, was calibrated against commercially available thermoluminescent dosimetry (TLD) (TLD-200 and TLD-100) using a bremsstrahlung (tube-based) x-ray source. Eight sampling sites within 1 to 20 km of the perimeter of the rare-earth facility were identified, the TLDs (silica- as well as TLD-200 and TLD-100) in each case being buried within the soil at fixed depth, allowing measurements to be obtained, in this case for protracted periods of exposure of between two to eight months. The values of the dose were then compared against values projected on the basis of radioactivity measurements of the associated soils, obtained via high-purity germanium gamma-ray spectrometry. Accord was found in relative terms between the TL evaluations at each site and the associated spectroscopic results. Thus said, in absolute terms, the TL evaluated doses were typically less than those derived from gamma-ray spectroscopy, by ∼50% in the case of PCFc-Ge. Gamma spectrometry analysis typically provided an upper limit to the projected dose, and the Marinelli beaker contents were formed from sieving to provide a homogenous well-packed medium. However, with the radioactivity per unit mass typically greater for smaller particles, with preferential adsorption on the surface and the surface area per unit volume increasing with decrease in radius, this made for an elevated dose estimate. Prevailing concentrations of key naturally occurring radionuclides in soil, 226Ra, 232Th and 40K, were also determined, together with radiological dose evaluation. To date, the area under investigation, although including a rare-earth processing facility, gives no cause for concern from radiological impact. The current study reveals the suitability of the optical fibre based micro-dosimeter for all-weather monitoring of low-level environmental radioactivity.
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Affiliation(s)
- Z Siti Rozaila
- Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
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Abdul Sani S, Hammond R, Jafari S, Wahab N, Amouzad Mahdiraji G, Siti Shafiqah A, Abdul Rashid H, Maah M, Aldousari H, Alkhorayef M, Alzimami M, Bradley D. Measurement of a wide-range of X-ray doses using specialty doped silica fibres. Radiat Phys Chem Oxf Engl 1993 2017. [DOI: 10.1016/j.radphyschem.2016.03.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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