Radiation Dosimetry Applications Research Articles

From reconstructed DICOM images to 3D printed models: anthropomorphic dosimetric phantoms

This study explores the construction of anthropomorphic dosimetric phantoms by leveraging Stereolithography (SLA) 3D printing technology and DICOM images processed through the Slicer software. This approach involves segmentation and processing of DICOM data bases of human subjects to extract specific anatomical structures that are to be converted into a format suitable for 3D printing. The objective is to create accurate models for radiation dosimetry applications. These phantoms hold great potential in advancing medical radiation research, allowing for more accurate and personalized assessments of radiation doses in various clinical scenarios.

Synthesis and luminescence characterizations of Ag and Na doped LiAlO2 for OSL dosimetry

Optically Stimulated Luminescence (OSL) materials are advanced technology materials widely used in critical applications from radiation dosimetry, biomedicine, and optical data storage to archaeometry. These materials store energy by trapping charge carriers and convert this energy back into light by optical stimulation. However, there are significant challenges such as control of trap distribution and complete understanding of luminescence mechanisms. This study aims to overcome these challenges by comprehensively investigating the luminescence characteristics of lithium aluminate (LiAlO2) pellet materials produced by the sol-gel method and enabling the development of a new OSL dosimetric material. The crystal structures of the synthesized materials were confirmed by X-Ray Diffraction (XRD) method and their morphologies were investigated by Scanning Electron Microscope (SEM). Detailed discussions on defect concentrations and lattice parameters of LiAlO2 are presented. To obtain promising luminescence signals for passive dosimetry, LiAlO2 were doped with various lanthanides (Ce and Gd) and metals (Cu, Ag, Na, Mg and Ca). Especially, the co-doping of Ag and Na ions provided a significant increase in Thermoluminescence (TL) and OSL signals. The effects of dopant elements on TL and OSL signals were investigated comprehensively, and the OSL components and lifetimes were analyzed in detail. As a result, it was determined that TL traps of the developed LiAlO2:Ag,Na pellets at 100 °C were the main source of OSL signals. The reusable OSL signals and almost linear dose-response ratio up to 2 Gy of this material make it a candidate for radiation dosimetry applications. While the developed LiAlO2:Ag,Na material exhibits promising OSL sensitivity and low fading over 2 weeks, the signal stability is dependent on an initial preheat treatment at 100 °C, which reduces around 80 % of the initial OSL signal associated with shallow traps. This characteristic supports the material’s application in dosimetry but may limit sensitivity in low-dose contexts.

Investigating the Suitability of Cu2ZnSnS4 Thin Films for Gamma Radiation Dosimetry Applications in Non-Medical Environments

Abstract The need for the replacement of cadmium, indium, and tellurium in their compounds for sensor applications is a novel study. The Cu2ZnSnS4 thin films were synthesized from Cu (99.99%), Sn (99.99%), and Zn (99.99%) using thermal evaporation method. The same volumetric parameters were maintained throughout the synthesis process. The films were further irradiated using an isotope of cesium-137 from a gamma source at different doses (0–0.6 kGy) and dose rates of 0.1007 kGy/hr at room temperature. Both the pristine and irradiated films were characterized with Raman spectroscopy, field emission scanning electron microscope (FESEM), energy dispersive X-rays (EDX), UV-Vis spectroscopy, and four-point probe techniques. The Raman results confirmed that all the films for both pristine and irradiated films have a main and secondary phases. The EDX results showed the pristine and 0.1 kGy films were Cu-rich film, while the 0.3 kGy and 0.6 kGy films turned out to be Zn-rich films with an increase in gamma dose. The optical property of all the films showed that the band gap decreased from 1.6 eV to 1.48 eV for the pristine and irradiated films. While the electrical resistivity results decreased after irradiation dose. The structural, optical, and electrical properties results responded linearly with the increasing gamma radiation dose, which suggested the possibility of using films as a new solid-state sensor to replace CdTe and CIGS thin films.

Optically stimulated luminescence properties of chicken eggshell derived hydroxyapatite for dosimetry applications

AbstractThis study investigated the optically stimulated luminescence (OSL) characteristics of hydroxyapatite (HAp) derived from chicken eggshells, a readily available bio-waste, for low-level radiation dosimetry applications which is less explored. The eggshells were employed as a calcium source in HAp synthesis. The X-ray diffraction and Fourier transform infrared spectroscopy results confirmed its purity and crystallinity. The OSL properties of the synthesized HAp demonstrated excellent reproducibility, reusability, and dose linearity up to 20 Gy, with a measurable dose range of 22 mGy. The favorable OSL characteristics, combined with the utilization of waste materials, offer significant advantages for environmental and medical radiation monitoring.

Spectroscopic Properties of TmF3-Doped CaF2 Crystals.

In this study, we report the growth and comprehensive spectroscopic analysis of TmF3-doped CaF2 crystals, grown using the vertical Bridgman method. The optical absorption and photoluminescence properties of both trivalent (Tm3+) and divalent (Tm2+) thulium ions were investigated. Optical absorption spectra in the UV-VIS-NIR range reveal characteristic transitions of Tm3+ ions, as well as weaker absorption bands corresponding to Tm2+ ions. The Judd-Ofelt (JO) formalism was applied to determine the intensity parameters Ω2, Ω4, and Ω6, which were used to calculate radiative transition probabilities, branching ratios, and radiative lifetimes for the Tm3+ ions. The emission spectra showed concentration-dependent quenching effects, with significant emissions observed for the concentration of 0.1 mol% TmF3 under excitation at 260 nm and 353 nm for Tm3+ ions and at 305 nm for Tm2+ ions. A new UV emission associated with divalent Thulium is reported. The results indicate that higher TmF3 concentrations lead to increased non-radiative energy transfer, which reduces luminescence efficiency. These findings contribute to the understanding of the optical behavior of Tm-doped fluoride crystals, with implications for their application in laser technologies and radiation dosimetry.

TL, EPR, and optical properties of undoped and Eu-, Ce-, Tb-, Sm-, Cu-, Mn-, and Li- doped MgSiO3 phosphors, synthesized by sol-gel combustion technique

Polycrystalline MgSiO3 samples, undoped or doped with rare earth- (Eu, Tb, Ce, Li, Sm), transition- (Mn and Cu), and alkali metal- (Li) elements, were prepared by the sol-gel combustion method and characterized by thermoluminescence, electron spin resonance, and optical properties. Enstatite and protoenstatite phases are observed in undoped and doped MgSiO3. Better TL results have been observed for phosphors doped with Tb, Ce, and Li (0.5 % mol). Fading experiments and the GCD method have been performed. EPR signals of gamma-irradiated phosphors indicate the formation of radiation-induced defect centers. Cu-doped MgSiO3 shows an unusual feature of the Cu2+ ion. The Cu2+ ion occupies a tetragonally compressed octahedral site, presenting an unconventional attribute. Optical bandgap value Eg is higher for the Ce, Tb, Mn, Li, Sm, and Cu-doped MgSiO3 phosphors. Ce, Li, and Tb dopant ions were found suitable for the MgSiO3 sample regarding its thermoluminescent response and its possible application in radiation dosimetry.

Characterization of a thermally stable red-light-emitting phosphor: synthesis, photoluminescence, and thermoluminescence studies of CsCaF3 compound doped with Eu3+ for solid-state lighting applications

In this investigation, we focused on the synthesis and characterization of CsCaF3 compound doped with europium (Eu3+) ions using a solid-state route. To analyze the crystal structure of the synthesized phosphors, X-ray diffraction analysis was employed. Additionally, the doped sample underwent examination of surface morphology and elemental composition through Field Emission Scanning Electron Microscopy and EDAX mapping. The color of the pure and doped CsCaF3 sample was quantified and fitted using Color coordinate graph by the Commission Internationale de l'Eclairage (CIE). The red emission on the doped CsCaF3 compound was detected at 465 nm, which is the transition from 5D0 to 7Fj (j = 0, 1, 2, and 3). The 0.5 mol. % Eu3+ doped CsCaF3 sample was found to have a color purity of 81% and an associated color temperature of 1660 K, indicating its suitability for aesthetic lighting applications. Furthermore, thermoluminescence study, electron paramagnetic resonance (EPR), and effective atomic number (Z eff) calculations were conducted to provide valuable information for potential radiation dosimetry applications.

Development of CaSO4:RE,Li (RE = Tm, Eu, Tb) composites for thermally or optically stimulated luminescence dosimetry

This work proposed the development of CaSO4:Tm,Li, CaSO4:Tb,Li and CaSO4:Eu,Li composites for application in radiation dosimetry, using luminescent techniques such as thermoluminescence (TL) and optically stimulated luminescence (OSL). The CaSO4 crystals were produced by the adapted slow evaporation route and characterized using X-ray diffraction (XRD), TL and OSL techniques. XRD analyses showed that the doped CaSO4 samples presented a single phase. The CaSO4:Eu,Li composites showed TL signals with peaks around 145 °C and 180 °C. The CaSO4:Tb,Li and CaSO4:Tm,Li composites showed TL signals with peaks centered at 165 °C and 275 °C. For the CaSO4:Tb and CaSO4:Tm samples, the addition of lithium as co-dopant resulted into a significant increase (2x) in the total TL signal of the samples. The CaSO4:Tm,Li samples presented a very intense OSL signal, about 80x greater than the signal of the other samples produced. This allows the applicability of TL/OSL detectors even more sensitives. The TL emission spectra of the samples showed typical emissions of Eu2+ ions (280 nm), Eu3+ (614 nm), Tb3+ (544 nm) and Tm3+ (455 nm). No emission corresponding to lithium was identified. All the samples produced showed linearity in the dose range used and good reproducibility, with variations below 10%. The CaSO4:Tm,Li samples showed the lowest limit of detection and fading. The evaluated dosimetric characteristics denote that these developed composites have potential application as TL/OSL detectors.

Investigation of structural, photo and thermoluminescence properties of YAGG:Ce nanogarnet for medical dosimetry application

Cerium-doped yttrium aluminum gallium garnet (YAGG:Ce3+) nanophosphors were synthesized using the sol-gel method. Mixed garnet of Y2.97Al5-xGaxO12:Ce0.03 was prepared with varying gallium content: x = 0, 1, 2 and 3 Ga. The effect of gallium substitutions on the structural, photo and thermoluminescence properties of the prepared nanophosphors were studied by X-ray diffraction (XRD), photoluminescence (PL) and thermoluminescence (TL) techniques. XRD results indicated that the single and pure cubic crystal phase was formed for all nanophosphor samples regardless of the Ga content. The PL spectra of all the samples exhibited a green-yellow emission band centered at 522 nm attributed to the 5d → 4f transitions of Ce3+ ions. The TL glow curve spectra recorded after β-particle irradiation showed a strong dependence in terms of position, shape and intensity, of all temperature peaks with the Ga content. The highest TL sensitivity was observed for the sample prepared with x = 2 Ga, with main peak arising at low temperature (85 °C). The sample prepared at x = 1 Ga exhibited also high TL sensitivity with a simple glow curve spectrum showing a main peak at high temperature (∼158 °C). Thus, the linear dose response of this sample has been investigated in the wide dose range from 0.125 to 100 Gy in order to evaluate the potentiality of this material for radiation dosimetry applications.

Effect of helium ion and gamma irradiation on the TL and OSL properties of Tb-doped LiF nanophosphors

Lithium Fluoride (LiF) stands out as a extensively researched material in Thermally Stimulated Luminescence Dosimetry (TLD). This study specifically delves into nanocrystalline Tb-doped LiF TL dosimeters, synthesized through the co-precipitation method, and evaluates their efficacy under He ion and gamma rays radiation. Morphological examination via transmission electron microscopy has revealed cubic-shaped particles. These particles were subjected to irradiation by 120 keV He ion beams ranging from 1014 to 1016 ions/cm2 and gamma rays ranging from 10 to 1000 Gy, facilitating a comprehensive comparative analysis. Deconvolution of the glow curves enabled the extraction of trapping parameters. Under gamma irradiation, the nanophosphor exhibited a distinctive, intense single TL glow peak centered at 400 K with a minor hump at 512 K, diminishing with increasing doses. Conversely, under He ion irradiation, the nanophosphor displayed a peak at 492 K, accompanied by a slight shoulder around 600 K. Additionally, gamma doses displayed a highly promising response to Optically Stimulated Luminescence (OSL). Fading studies further underscore its suitability for radiation dosimetry applications. The unique characteristics of the TL glow curve, dose-response behaviours, and OSL responses highlight the versatility and effectiveness of these nanophosphors in radiation dosimetry, making significant contributions to advancements in this field.

Experimental evaluation of electrospun ZnO/WO3/PVA-coated glass nanocomposites for a potential radiation dosimetry application

This research aimed to fabricate a potential radiation dosimeter using electrospun ZnO/WO3/PVA-coated glass nanocomposites. Samples with varying ZnO molarities (2.46, 3.69, 4.91, 5, and 7 M) and 5 wt% of WO3 collected at different times were examined. Field emission scanning electron microscopy (FESEM) and energy dispersive X-ray analysis (EDX) revealed favorable nanofiber morphology, although certain conditions produced larger nanofibers. The optical properties, analyzed via ultraviolet–visible (UV–Vis) spectroscopy, exhibited varying responses in different samples with changes in nanofiber collection time. The calculated optical energy band gap (Eg) for all samples is lower than Eg of pure ZnO. Moreover, the effective atomic number (Zeff), calculated based on EDX results, did not approach Zeff of human tissues, in all samples in general. Crucially, all samples demonstrated a strong linear response and low energy dependence when subjected to different X-ray exposure settings, closely resembling an Al2O3-based OSL dosimeter. Sample E3, consisting of 7.00 M ZnO and 5 wt% of WO3 collected over 4 h, emerged as the most promising candidate for a radiation dosimeter. Prior studies neglected to examine the influence of different amounts of ZnO on the radiation dosimetry properties of ZnO/WO3/PVA nanofibers. In contrast, this study specifically investigated the radiation dosimetry properties of ZnO/WO3/PVA nanofibers. The exceptional properties of ZnO in response to X-rays, combined with the desired X-ray attenuation capabilities of WO3, make them a distinct option as substitute materials in radiation dosimeters. This research paves the way for an alternative dosimeter solution with robust radiation detection capabilities.

Radiophotoluminescence properties of Bi-doped NaCaBO3

Bi-doped NaCaBO3 exhibits radiophotoluminescence (RPL) properties, where the Bi2+ centre is formed through X-ray irradiation. As a result of RPL, a broad emission band appears around 800 nm in the photoluminescence (PL) spectrum, attributed to X-ray irradiation. The intensity of the PL signal is proportional to the irradiation dose, making it useful for measuring accumulated radiation dose. The sensitivity depends on the doping concentration of Bi, and the optimal concentration to maximize sensitivity is approximately 0.005%. With a laboratory-constructed reader system, the optimal sample enables measurement of X-ray dose as low as 25 mGy. Following irradiation, the Bi2+ signal slightly increases by about 13%, but it is significantly reduced to around 7% of the initial value after heat treatment at 500°C for 100 s. The formation and annihilation of the Bi2+ centre can be reproduced multiple times. Therefore, RPL of Bi-doped NaCaBO3 is attractive for radiation dosimetry applications.

Luminescence Properties of Ce-Doped Di-Calcium Magnesium Disilicate Ca2MgSi2O7:4 mol%Ce

Dicalcium magnesium disilicate (Ca2MgSi2O7) doped with cerium rare earth ions has been examined for its optical and photonic characteristics and applicability for radiation dosimetry applications. Mono-calcium aluminate that has cerium added to it, has been shown to be an excellent dosimeter with a linear response up to roughly 4 kGy of radiation exposures. Maximum TL emission is achieved at 4 mol% cerium dopant concentration. The clearly visible two peaks that were detected at 381.13K and 566.87K can be used as a high-temperature dosimetry advance. In this study, we reported the preparation technique and luminescence properties such as TL, ML, and PL of Ce3+ doped dicalcium magnesium silicate phosphors. The phosphors were prepared by the solid-state reaction method. The TL glow curves were recorded for all different concentrations of Ce- doped phosphors.

Anomalous heating rate effect in GdAl3(BO3)4:Dy3+ under beta radiation stimulation: Analysis of dose response and kinetic parameters

This study presents a comprehensive investigation into the thermoluminescence (TL) properties of Dy3+-activated gadolinium aluminate garnet (Dy3+:GdAl3(BO3)4 or Dy3+-GAB) phosphor materials. The research aims to unravel the intricate interplay among heating rate, radiation dose, and TL glow curve responses to optimize dosimetry applications. The TL response of the material is scrutinized across diverse heating rates (HR) and dose levels, while accounting for temperature lag correction. Concentration quenching effects are explored through Dy3+ concentrations spanning from 0.5 to 7 wt%, revealing the optimal doping concentration to be 3 wt%. The study underscores the critical role of choosing an appropriate band-pass filter, revealing the effectiveness of the “IRSL-TL wideband blue” filter's in capturing TL signals. Furthermore, the study examines kinetic parameter estimated using different approaches and shedding light on how heating rate and radiation dose affect activation energy values. Intriguingly, the study observes an anomalous heating rate effect, resulting in elevated TL peak intensities at higher HR. This effect is attributed to non-radiative transitions and the semi-localized transition model. The reusability of Dy3+-doped GAB is also examined, confirming its consistency and reproducibility across multiple uses. This study significantly contributes to the advancement of TL dosimetry methodologies and enhances our understanding of luminescent material behaviours. We utilized both the Tm-Tstop technique in conjunction with the Initial Rise (IR) method and Computerized Glow Curve Deconvolution (CGCD) techniques, revealing the presence of seven overlapping glow peaks alongside the main ones. Both methods appear to provide excellent agreement in terms of activation energy values, ranging from 0.70 to 1.50 eV for each peak. Furthermore, the findings strongly indicate the effective utilization of TL signals in radiation dosimetry applications.

Synthesis and evaluation of Li2O-2B2O3 glass chips for gamma radiation dosimetry applications

We report the fabrication of 10 mm × 10 mm × 1 mm, Li2O-2B2O3 glass chips using melt quench method. Melt produced due to solid state reaction between Li2CO3 and H3BO3 at 950°C, quenched at stainless steel die and annealed at 350°C resulted in production of highly transparent glass chips. Glass chips irradiated to various gamma radiations and thermo-luminescence measurement performed using linear temperature profile with heating rate 2°C/s. A broad glow curve is obtained with peak at 185°C. Further linearity of TL response with gamma dose studied in gamma dose range 100 mGy to 50 Gy. TL intensity and integrated counts are found linearly with gamma dose. The TL sensitivity of glass chips were found to be ∼52 counts/mGy. Repeatability of TL Dosimetric performance is found to be within ±10% and dose rate dependence is also found within ±10% in 50 mGy/hr to 3000 mGy/hr dose rate range. The prepared glass chips can be utilized as thermo-luminescent dosimeter for gamma dose 100 mGy and higher.

Thermoluminescence dosimeter (TLD) studies of Ca10 K(PO4 )7 :Dy phosphor for applications in radiation dosimetry.

This study reports the thermoluminescence (TL) aspects of Ca10 K(PO4 )7 :Dy phosphor synthesized using a wet chemical method for the first time. The X-ray diffraction (XRD) results confirm the formation of the desired crystalline phase. Surface morphological studies reveal the formation of polyhedrons and agglomerations having an average diameter of 200 nm, while energy dispersive X-ray spectroscopy (EDS) data show the presence and composition of the elements in appropriate amounts. The effect of Dy doping concentration has been studied on the TL properties with exposure to gamma radiations from the Co-60 source. The best TL response has been observed for 5mol% Dy doping concentration. The glow curve is simple and consists of a single peak at 130°C. The effect of the heating rate has been studied on the TL glow curve, and the heating rate of 5°C/s shows the best TL response. The various TL properties such as annealing conditions, dose-response, TL linearity, fading, and reusability of the prepared phosphor have been studied to check its suitability as a good TL dosimeter (TLD). TL characterization of the phosphor reports that the TL response is linear from 5- to 2000 Gy. The results show that this phosphor can be a good TLD for the dosimetry of gamma radiations from Co-60.

Unravelling the impact of unusual heating rate, dose-response and trap parameters on the thermoluminescence of Sm3+ activated GdAl3(BO3)4 phosphors exposed to beta particle irradiation

The thermoluminescence of GdAl3(BO3)4 (GAB) doped with various concentrations of Sm3+ (i.e. from 0.5 to 7 wt%), prepared by gel combustion, was studied. TL glow peaks at 78 °C and 225 °C are observed. The intensity of the glow peak at 225 °C increased with a faster heating rate. To gain insight into the trap activation energies, the methods of Hoogenstraaten and Booth-Bohun-Parfianovitch were used, where the calculated activation energies are 0.57 eV and 0.60 eV for Peak I and 1.69 eV and 1.71 eV for Peak II respectively. The dose-response of GAB:0.5 wt%Sm3+ demonstrates robust linearity up to 40 Gy, with a strong correlation coefficient of 0.999. Both TM-Tstop combined with the Initial Rise (IR) and Computerized Glow Curve Deconvolution (CGCD) techniques were employed, which revealed six overlapping glow peaks beneath the main peaks. Additionally, the results suggest that the TL signal can be efficiently exploited for radiation dosimetry applications.

Multifunctional properties of tin oxide nanoparticles synthesized by green and chemical approach

Herein, we report the synthesis of SnO2 nanoparticles by combustion method using two reducing agents. One with urea as a fuel (SnO2U) and another one with Azadirachtaindica leaves extract as a reducing agent (SnO2N) and calcined at 500oC for 3 hrs. The synthesized samples are characterized using different techniques. The Bragg reflections confirms the formation of pure tetragonal SnO2 NPs. The surface morphological analysis clearly indicates the formation of irregular shaped agglomerated NPs. The agglomeration and particle size was found to be more in SnO2U NPs. The estimated direct energy bandgap using Tauc's relation was found to be 3.75 and 3.37 eV for SnO2U and SnO2N respectively. Further, Photoluminescence excitation, emission, CIE and CCT analysis was performed. Thus, the present sample might be used as a nanophosphor material in Cool and Warm blue light emitting diodes. The cytotoxic properties against HeLa and MCF7 cells and compared the percentage of viability and cell death with standard chemotherapy drug Cisplatin. Theoretically, X-ray/gamma ray absorption properties such as mass attenuation coefficient (MAC) SnO2U and SnO2N NPs were evaluated which might finds an application in nuclear radiation dosimetry.

Nanocomposite scintillation perovskite-delignified wood photonic guides for X-ray imaging

Nanocrystalline scintillators with low-cost, fast response, and high light yield are widely used for X-ray imaging. However, they fail in high-energy X-ray imaging because of the fundamental limitations due to lateral radiation spreading in thicker device-compatible active layers. This issue is resolved by using the novel nanocomposite containing CsPbBr3 scintillation single-microcrystalites embedded into transparent, natural wood-derived light-guiding fibrous structures. The CsPbBr3 crystals convert X-ray to visible photons with a high photoluminescence quantum efficiency (76 %), and an average fast photoluminescence decay time of 25.9 ns. The delignified wood-derived fiber-like lumina effectively guide light, while suppressing the lateral spreading of scintillation photons. This unique porous nanocomposite material offers an excellent X-ray detection performance, and linear response in a wide parameter range. The developed scintillator screen achieves well-resolved, high-contrast X-ray imaging, featuring a very high spatial resolution of 11.9 lp/mm at a modulation transfer function of 0.2, thus exceeding the benchmark industry standards and offering a new advanced materials platform for radiation detection and dosimetry applications.

Prompt gamma ray activation analysis for determining chemical composition of 3D printing and casting materials used in biomedical applications.

Three-dimensional printing and casting materials were analyzed by prompt gamma-ray activation analysis (PGAA) to determine their suitability as human tissue surrogates for the fabrication of phantoms for medical imaging and radiation dosimetry applications. Measured elemental compositions and densities of five surrogate materials simulating soft tissue and bone were used to determine radiological properties (x-ray mass attenuation coefficient and electron stopping power). When compared with radiological properties of International Commission on Radiation Units and Measurements (ICRU) materials, it was determined that urethane rubber and PLA plastic yielded the best match for soft tissue, while silicone rubber and urethane resin best simulated the properties of bone.