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ABSTRACT In this article, we report the synthesis of Na2Sr1- x(PO4)F:Eu x phosphor via a combustion method. The influence of different annealing temperatures on the photoluminescence properties was investigated. The phosphor was excited at both 254 and 393 nm. Na2Sr1- x(PO4)F:Eu x3+ phosphors emit strong orange and red color at 593 and 612 nm, respectively, under both excitation wavelengths. Na2Sr1- x(PO4)F:Eu x3+ phosphors annealed at 1050°C showed stronger emission intensity compared with 600, 900 and 1200°C. Moreover, Na2Sr1- x(PO4)F:Eu x3+ phosphor was found to be more intense when compared with commercial Y2O3:Eu3+ phosphor. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT This article reports on the optical properties of 0.5% mol of Sm3+, Dy3+ ion-doped B2O3-TeO2-Li2O-AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd-Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm3+ and Dy3+:LiAlFBT glasses showed a bright reddish-orange emission at 598 nm (4G5/2 → 6H7/2) and an intense yellow emission at 574 nm (4F9/2 → 6H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm3+ and Dy3+:LiAlFBT glasses. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Study aimed at Monte Carlo (MC) modeling and dosimetric validation of GammaMed Plus 192 Ir source for high dose rate brachytherapy using Geant4 code in TOPAS. Study investigated the several TG-43 guided dosimetric parameters for brachytherapy dose calculation. The excellent agreement was found between simulated and published data. The simulated MC dataset can be served as reference and fed into Treatment planning system (TPS) to verify brachytherapy dose calculation. Present MC modeling of brachytherapy source can be availed in further patient specific studies involving MC simulation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Phosphites are being recognized as the new emerging candidates for luminescence in the modern era. In the proposed research article, Ce 3+ /Eu 2+ co-activated NaBa(PO 3 ) 3 phosphite phosphors synthesized utilizing sol-gel technique. Through the use of XRD and Rietveld refinement, the phase identity and crystal structure of produced phosphor are examined. SEM is employed to analyze the morphology and elemental composition of the prepared sample. The sample shows blue emission enhancement in the phosphor on energy transfer with the Ce 3+ ion by 6 times. This highly instance blue emitting phosphor has color purity of 98.49%. These all results confirm that the prepared phosphor is potential candidate for WLEDs, display applications and blue emitting phosphor for plant cultivation applications., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: This study investigates dosimetric influence and gradient-analysis of leaf-width of various Multi-leaf-collimators (MLC) from Truebeam and Halcyon linear accelerators., Methods: The leaf-width effects of Millennium120 and HD120MLC from Truebeam and SX1 and SX2 from Halcyon were studied using virtual phantom in Eclipse16.1.2 TPS. Target structures consist of bore and wave cylinders of equally spaced projected Planning target volume (PTV) of diameters ranging from 1-to-5 cm and 20 cm length. Treatment plans for all PTVs, and four different MLCs configurations from both machines were created utilizing 6MVFFF beam to deliver dose of 50Gy/25# using IMRT and VMAT. Plans were evaluated using plan quality indices including dose conformity, homogeneity, gradient radius, and Monitor-unit (MU). Also, dose gradients were analyzed by estimating distinct integral volume V D% and paired-t-tests were performed to evaluate statistical differences., Results: All the plan satisfied the minimum criteria of D 95 % ≥prescription dose and V 107 % ≤2cc. Mean conformity and homogeneity indices for SX1MLC(CI = 0.680,HI = 0.022) were found significantly higher and lower than SX2(CI = 0.746,HI = 0.016), Millennium120 (CI = 0.739,HI = 0.012), and HD120MLC(CI = 0.745,HI = 0.017), respectively. However, CI and HI for SX2, Millennium120, and HD120MLC found comparable. Gradient radius enclosing 50 % of isodose observed maximum and minimum for SX1 and HD120MLC, respectively. Plan MUs for Truebeam MLCs were found approximately 25 % higher than Halcyon MLCs. Dose distribution generated using SX2 and Millennium120 found comparable, however p ≤ 0.05 ascertained substantial differences among SX1, Millennium120, and HD120MLC., Conclusion: MLC leaf-width influences intensity-modulation and significantly alters dosimetric outcome depending on the magnitude of the leaf-width. HD120MLC does not show much significant advantages over SX2 and Millennium120 except gradient control., Implications for Practice: Halcyon SX1MLC produces least effective plan compared to all other MLC types. However, SX2 and Millennium120 can produce plans of comparable quality except plan MUs difference., Competing Interests: Conflict of interest statement Authors declare no conflict of interest., (Copyright © 2024 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.)

A fluoride material phosphor doped with rare earth ions Eu 3+ and Dy 3+ was studied for its photoluminescence (PL) properties. The material was synthesized using a combustion method and characterized using X-ray diffraction (XRD) and PL techniques. The Na 3 Ca 2 (SO 4 ) 3 F: Eu 3+ phosphor exhibits two distinct peaks at 593 nm (orange) and 615 nm (red) at an excitation wavelength of 395 nm. The PL excitation spectrum of the Na 3 Ca 2 (SO 4 ) 3 F: Dy 3+ phosphor showed series of peaks, corresponding to the 4f → 4f transitions of Dy 3+ ions. Under 350-nm excitation, the PL emission spectrum revealed two prominent bands one at 483 nm (blue region) due to the 4 F₉ / ₂ →  6 H₁₅ / ₂ transition, and another at 573 nm (yellow region) resulting from the 4 F₉ / ₂ →  6 H₁₃ / ₂ transition. These blue and yellow emissions suggest potential applications in solid-state lighting, particularly for mercury-free excitation sources. Rare earth-doped Eu 3+ /Dy 3+ materials exhibit highly efficient PL properties, making them suitable candidates for white light-emitting diodes (LEDs) or other solid-state lighting phosphors., (© 2024 John Wiley & Sons Ltd.)

Biofilm is a common problem associated with human health. Pathogenicity and increase in resistance of bacteria require urgent development of effective ways for the treatment of bacterial diseases. Different strategies have been developed for the treatment of bacterial infections among which nanoparticles have shown greater prospects in battling with infections. Biofilms are resistant microbial colonies that possess resistance and, hence, cannot be killed by conventional drugs. Nanoparticles offer new avenues for treating biofilm-related infections involving multi-drug resistant organisms. They possess great antibiofilm properties, disrupting cell architecture and preventing colony formation. Green-synthesised nanoparticles are more effective and less toxic to human cells than commercially available or chemically synthesised antibiofilm nanoparticles. This review summarises the antibiofilm efficiency of plant-mediated nanoparticles and knowledge about biofilm inhibition., (© 2024 John Wiley & Sons Ltd.)

One of the exciting developments in contemporary luminescence research is the development of rare earth triggered luminescent glasses, which are a type of lanthanide activated luminous material. For the first time, Ce 3+ , Eu 3+ activated/co-activated Mg 21 Ca 4 Na 4 (PO 4 ) 18 orthophosphate glasses have been synthesized using the proposed work's melt quenching technique. The proposed glass sample's XRD pattern has an amorphous character, although its most prominent peak matches data from the Mg 21 Ca 4 Na 4 (PO 4 ) 18 standard ICSD database. FT-IR analysis was used to analyze the proposed glass sample's vibrational characteristics. Co-activated Mg 21 Ca 4 Na 4 (PO 4 ) 18 glass exhibits large emission peaks under UV excitations that cover the far red area during a photoluminescence examination. These outcomes demonstrate the proposed sample's value in applications such as WLEDs and plant cultivation., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This study describes the luminous properties of Pb 5 (PO 4 ) 3 Br doped with RE 3+ (RE = Dy 3+ , Eu 3+ and Tb 3+ ) synthesised using the solid-state method. The synthesised phosphor was characterised using Fourier-transform infrared, X-ray diffraction, scanning electron microscopy and photoluminescence measurements. Dy 3+ -doped Pb 5 (PO 4 ) 3 Br phosphor exhibited blue and yellow emissions at 480 and 573 nm, respectively, on excitation at 388 nm. Eu 3+ -doped Pb 5 (PO 4 ) 3 Br phosphor exhibited orange and red emissions at 591 and 614 nm, respectively, on excitation at λ ex  = 396 nm. Pb 5 (PO 4 ) 3 Br:Tb 3+ phosphor exhibited the strongest green emission at 547 nm on excitation at λ ex  = 380 nm. Additionally, the effect of the concentration of rare-earth ions on the emission intensity of Pb 5 (PO 4 ) 3 Br:RE 3+ (RE 3+  = Dy 3+ , Eu 3+ and Tb 3+ ) phosphors was investigated., (© 2024 John Wiley & Sons Ltd.)

Visible and near-infrared (NIR) upconversion luminescence (UCL) emissions originating from the BaY 2 F 8 : Yb 3+ , Tm 3+ systems were investigated under a laser excitation at 980 nm. The BaY 2 F 8 :20 mol% Yb 3+ , x mol% Tm 3+ and BaY 2 F 8 : y mol% Yb 3+ , 0.5 mol% Tm 3+ phosphors showed prominent UCL at 800 and 810 nm. The optimized doping concentrations of Yb 3+ and Tm 3+ in the BaY 2 F 8 host matrix were evaluated, their spectroscopic properties were determined, and studies on their temperature-dependent behaviour were carried out. The temperature-sensing properties were studied by generating the fluorescence intensity ratio (FIR) of the UCL peaks originating from the thermally-coupled energy levels of the Tm 3+ ions. The Stark sublevels of 1 G 4 level of Tm 3+ ions were utilized to estimate the temperature-sensing abilities of the phosphor., (© 2023. The Author(s).)

In recent trends, radiation falls under the narrowband ultraviolet-B region (305-315 nm) widely used in phototherapy lamp applications in the treatment of skin diseases. In this paper, we report a Gd 3+ -doped NaYF 4 luminescent material synthesized for the first time using the low-temperature co-precipitation method. It crystallized into a face-centred cubic structure, as confirmed by X-ray diffraction characterization techniques and Rietveld refinement. The photoluminescence property of the as-prepared sample shows a highly intense, sharp emission band obtained at 311 nm, which belongs to the narrowband ultraviolet-B region and corresponds to the transition of the 6 P 7/2 → 8 S 7/2 level of the Gd 3+ ions under 272 nm excitation ( 8 S 7/2 to 6 I J ). The transitions of the Gd 3+ ions are detected entirely with different concentrations of Gd 3+ ions. Scanning electron microscopy analysis indicated that the average particle was 288 nm. The critical distance for energy transfer was calculated to be equal to 11.5017 Å. Dipole-dipole interaction is responsible for energy transfer, as analyzed by Dexter theory. These excellent optical characteristics, together with their highly efficient and low-cost synthesis approach, indicate that synthesized NaYF 4 :Gd 3+ phosphors have excessive potential for phototherapeutic lamp applications., (© 2024 John Wiley & Sons Ltd.)

A series of SrAlBO 4 :Eu phosphors doped with different concentrations of Eu (0.1, 0.3, 0.5, 0.7, 1.0 mol%) was synthesized using a solid-state diffusion method, and their thermoluminescence (TL) properties were analyzed for gamma and carbon ion irradiation. The phase purity, morphological properties, vibrational features, and thermal stability of the prepared sample were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric/differential thermal analyzer (TG/DTA) techniques, respectively. The TL properties of the proposed materials showed broad dosimetric bands, peaking at 202°C for 0.12 kGy gamma irradiation. The highest TL intensity was obtained for a 0.7 mol% concentration of Eu ions under gamma irradiation. Furthermore, the glow curve of the proposed materials showed a broad emission band, centred at 148°C under carbon ion beam irradiation and exhibited the highest emission intensity for a 0.1 mol% Eu concentration. In addition, the dosimetric trapping parameters of the prepared samples such as symmetry factor, order of kinetics, activation energy, and frequency factor, were analyzed using various methods such as Chen's peak shape method, initial growth method, and the Ilich method. The obtained results of the samples showed the potential for dosimetric application., (© 2023 John Wiley & Sons, Ltd.)

Cymbopogon citratus-mediated pure aluminium oxide (Al 2 O 3 ) and europium (Eu)-doped Al 2 O 3 with different amounts of metal ion were prepared using a green synthesis method. Synthesised nanoparticles were characterised by ultraviolet (UV)-visible spectroscopy, photoluminescence (PL), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Synthesis of nanoparticles is confirmed by using UV-visible spectroscopy showing maximum absorption at 411 and 345 nm for Al 2 O 3 and Eu-doped Al 2 O 3 , respectively. The antibacterial activity of prepared nanoparticles was evaluated against Pseudomonas aeruginosa, Streptococcus aureus, Escherichia coli and Klebsiella pneumoniae using a well-diffusion technique. The effect of pure Al 2 O 3 and Eu-doped nanoparticles shows excellent results against P. aeruginosa, S. aureus, E. coli and K. pneumoniae., (© 2023 John Wiley & Sons Ltd.)

Red and green rare-earth ion (RE 3+ ) (RE = Eu, Tb):MgLa 2 V 2 O 9 micro-powder phosphors were produced utilizing a standard solid-state chemical process. The X-ray diffraction examination performed on the phosphors showed that they were crystalline and had a monoclinic structure. The particles grouped together, as shown in the scanning electron microscopy (SEM) images. Powder phosphors were examined using a variety of spectroscopic techniques, including photoluminescence (PL), Fourier-transform infrared, and energy dispersive X-ray spectroscopy. Brilliant red emission at 615 nm ( 5 D 0  →  7 F 2 ) having an excitation wavelength (λ exci ) of 396 nm ( 7 F 0  →  5 L 6 ) and green emission at 545 nm ( 5 D 4  →  7 F 5 ) having an λ exci  = 316 nm ( 5 D 4  →  7 F 2 ) have both been seen in the emission spectra of Tb 3+ :MgLa 2 V 2 O 9 nano-phosphors. The emission mechanism that is raised in Eu 3+ :MgLa 2 V 2 O 9 and Tb 3+ :MgLa 2 V 2 O 9 powder phosphors has been explained in an energy level diagram., (© 2023 John Wiley & Sons Ltd.)

Light is the most important component in plant growth and development. This study synthesised a novel Mn 4+ -doped K 2 LiAlF 6 red-emitting phosphor using the coprecipitation method. We observed that on addition of dopant Mn 4+ ions to the host K 2 LiAlF 6 , its phase changed from rhombohedral to cubic due to the change in the lattice position of the atoms. When the atoms are excited at 468 nm, the K 2 LiAlF 6 :Mn 4+ phosphor exhibited a red emission band ranging from 630 to 700 nm, centred at 638 nm, which matched well with the absorption spectra of phytochrome PR. The critical quenching content of Mn 4+ ions was ~3 mol%. The critical distance between Mn 4+ ions was determined to be 19.724 Å, and non-radiative energy transfer among the nearest-neighbour Mn 4+ ions was the mechanism used for the concentration quenching effect. The Commission International de l'Eclairage (CIE) chromaticity coordinates of the K 2 LiAlF 6 :0.03 Mn 4+ sample were (x = 0.7162, y = 0.2837). The luminescence mean decay time was calculated to be 8.29 ms. These results demonstrated the promising prospect of K 2 LiAlF 6 :Mn 4+ as a red-emitting phosphor for application in red light-emitting diodes for plant cultivation., (© 2023 John Wiley & Sons Ltd.)

In the present report, Aegle marmelos leaf powder was used to synthesize copper nanoparticles (CuNPs) using a simple and cost-effective method. A. marmelos leaves have various medicinal uses including for the treatment of diarrhoea, constipation, diabetes, cholera, skin diseases, earache, blood purification, heart problems, and so on. The plant biomolecules induce the reduction of Cu 2+ ions to CuNPs and also act as a capping and stabilizing agent. The formation of CuNPs was confirmed using photoluminescence (PL) excitation and emission spectra on a Shimadzu RF-5301 PC spectrofluorophotometer and the absorbance spectra of a UV-visible spectrophotometer at different stages during the synthesis process. In addition, other properties of synthesized CuNPs were also investigated using X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy techniques. The average size of the synthesized CuNPs was in the range 20-40 nm. Furthermore, the synthesized NPs were also considered for an antimicrobial study against Gram-positive Staphylococcus aureus and Proteus, and Gram-negative Escherichia coli and Salmonella spp. using the agar well diffusion method. The zone of inhibition against the Gram-positive bacteria was greater than the zone of inhibition against the Gram-negative bacteria. These investigation results suggest that synthesized NPs are promising nanomaterials for use as antimicrobial agents., (© 2023 John Wiley & Sons Ltd.)

The CaAlBO 4 :RE (RE = Dy 3+ , Eu 3+ , Sm 3+ ) phosphor were prepared via combustion synthesis and studied by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), photoluminescence (PL) spectra and CIE coordinates. The phase formation of the obtained phosphor was analyzed by XRD and the result was confirmed by standard PDF Card No. 1539083. XRD data successfully indicated pure phase of CaAlBO 4 phosphor. The crystal structure of CaAlBO 4 phosphor is orthorhombic with space group Ccc2 (37). The SEM image of CaAlBO 4 phosphor reveals an agglomerated morphology and non-uniform particle size. The EDS image provides evidence of the elements present and the chemical makeup of the materials. Under the 350 nm excitation, the emission spectrum of Dy 3+ activated CaAlBO 4 phosphor consists of two main groups of characteristic peaks located at 484 and 577 nm which are ascribed to 4 F 9/2  →  6 H 15/2 and 4 F 9/2  →  6 H 13/2 transition of Dy 3+ respectively. The PL emission spectra of CaAlBO 4 :Eu 3+ phosphor shows characteristics bands observed around 591 and 613 nm, which corresponds to 5 D 0  →  7 F 1 and 5 D 0  →  7 F 2 transition of Eu 3+ respectively, upon 395 nm excitation wavelength. The emission spectra of Sm 3+ activated CaAlBO 4 phosphor shows three characteristic bands observed at 565, 601 and 648 nm which emits yellow, orange and red color. The prominent emission peak at the wavelength 601 nm, which is attributed to 4 G 5/2  →  6 H 7/2 transition, displays an orange emission. The CIE color coordinates of CaAlBO 4 :RE (RE = Dy 3+ , Eu 3+ , Sm 3+ ) phosphor are calculated to be (0.631, 0.368), (0.674, 0.325) and (0.073, 0.185). As per the obtained results, CaAlBO 4 :RE (RE = Dy 3+ , Eu 3+ , Sm 3+ ) phosphor may be applicable in eco-friendly lightning technology., (© 2023 John Wiley & Sons Ltd.)

Phosphites are the new emerging candidates in the field of luminescence in the modern era. In the present investigation, Tb 3+ /Eu 3+ activated/co-activated LiAl(PO 3 ) 4 phosphor was prepared by a wet chemical method, and the effect of R + (Na + , K + ) ions on photoluminescence (PL) properties of these phosphors are investigated. Phase identification and crystal structure of the prepared phosphor were determined using XRD and Rietveld refinement, respectively. Morphological study and elemental analysis of the proposed phosphor with elemental analysis of the sample were performed using SEM and EDS. The PL properties of the proposed phosphor showed three simultaneous emission peaks in the visible range, giving color-tunable emission. The charge compensation of Na + and K + ions make a significant impact on the PL intensity of Tb 3+ , Eu 3+ co-activated LiAl(PO 3 ) 4 phosphors. The PL intensity of Tb 3+ , Eu 3+ co-activated LiAl(PO 3 ) 4 phosphors was significantly enhanced by factors 1.2 and 1.4 when Na + and K + charge compensators, respectively, were introduced. To manifest the charge compensation effect of alkali metals the optimum intense sample in the co-doped sample was used. These results indicate the potential candidacy of the studied phosphor for further improvement in PL properties for application in solid-state lighting., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A series of ZnB 2 O 4 phosphors doped with different concentrations of Eu and Dy (0.05 0.1, 0.2, 0.5, 1.0 mol%) and co-doped with Ce (1, 2, 5, 7, 10 mol%) respectively was prepared via the solid-state reaction technique and the thermoluminescence (TL) behaviour of gamma ray-irradiated samples was studied. The synthesized samples were irradiated with γ-rays for the dose range 0.03-1.20 kGy. The TL intensity variations with dose, dopant concentration, and the effect of co-doping were studied. The TL response curves for ZnB 2 O 4 :Eu 3+ and ZnB 2 O 4 :Dy 3+ , ZnB 2 O 4 :Eu 3 ,Ce 3+ and ZnB 2 O 4 :Dy 3+ ,Ce 3+ phosphor were observed. It was revealed that ZnB 2 O 4 :Eu 3+ showed a linear TL behaviour for the dose 0.03-1.20 kGy and ZnB 2 O 4 :Dy 3+ showed linearity for the gamma dose range 0.03-0.10 kGy. Furthermore, fading for all the samples was observed to be less than 10% for a storage period of 30 days. In addition to this, the trapping parameters, especially activation energies were evaluated using the Ilich method and the initial rise method. The activation energy values obtained from both methods were in complete agreement with each other., (© 2023 John Wiley & Sons Ltd.)

Background: This study aimed to evaluate the dosimetric influence of 6-dimensional (6D) interfractional setup error in tongue cancer treated with intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) using daily kilovoltage cone-beam computed tomography (kV-CBCT)., Materials and Methods: This retrospective study included 20 tongue cancer patients treated with IMRT (10), VMAT (10), and daily kV-CBCT image guidance. Interfraction 6D setup errors along the lateral, longitudinal, vertical, pitch, roll, and yaw axes were evaluated for 600 CBCTs. Structures in the planning CT were deformed to the CBCT using deformable registration. For each fraction, a reference CBCT structure set with no rotation error was created. The treatment plan was recalculated on the CBCTs with the rotation error (R Error ), translation error (T Error ), and translation plus rotation error (T+R Error ). For targets and organs at risk (OARs), the dosimetric impacts of R Error , T Error , and T+R Error were evaluated without and with moderate correction of setup errors., Results: The maximum dose variation ΔD (%) for D 98% in clinical target volumes (CTV): CTV-60, CTV-54, planning target volumes (PTV): PTV-60, and PTV-54 was -1.2%, -1.9%, -12.0%, and -12.3%, respectively, in the T+R Error without setup error correction. The maximum ΔD (%) for D 98% in CTV-60, CTV-54, PTV-60, and PTV-54 was -1.0%, -1.7%, -9.2%, and -9.5%, respectively, in the T+R Error with moderate setup error correction. The dosimetric impact of interfractional 6D setup errors was statistically significant (p < 0.05) for D 98% in CTV-60, CTV-54, PTV-60, and PTV-54., Conclusions: The uncorrected interfractional 6D setup errors could significantly impact the delivered dose to targets and OARs in tongue cancer. That emphasized the importance of daily 6D setup error correction in IMRT and VMAT., Competing Interests: Conflict of interest The authors have no conflicts of interest to declare that are relevant to the content of this article, (© 2023 Greater Poland Cancer Centre.)

The accuracy and uncertainty of the automated image registration (AIR) algorithm in a six-dimensional (6D) kilovoltage cone-beam computed tomography (kV-CBCT) image-guided radiation therapy (IGRT) system were evaluated with a concurrent analysis of machine performance check (MPC). The MPC was performed before (MPCpre) and after (MPCpost) each accuracy and intrinsic uncertainty measurement. The accuracy was evaluated for 25 sets of the known shifts applied to the Catphan-504 phantom through a 6D robotic couch in the head, thorax, and pelvis CBCT acquisition modes. The uncertainty was evaluated for the intensity range, soft tissue, and bone matching filters in the head, thorax and pelvis CBCT acquisition modes. The mean ΔMPC (MPCpost-MPCpre) for all test parameters was within 0.02 ± 0.08 mm and 0.00 ± 0.02°. The overall average accuracy in AIR of 6D kV-CBCT IGRT in all translational and rotational axes was within 0.05 ± 0.76 mm and 0.02 ± 0.07°, respectively, for all CBCT modes. The overall mean population (Mpop), systematic (Σ) and random (σ) errors were within 0.47, 0.53 and 0.24 mm and within 0.03, 0.08 and 0.07° in translational and rotational axes, respectively, for all matching filters in all CBCT modes. The accuracy and intrinsic uncertainty in the AIR of the 6D kV-CBCT IGRT were within acceptable limits for clinical use., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The luminescent properties and energy transfer (ET) mechanism in the Ln 3+ pair of the RE 3+ (RE = Eu 3+ , Ce 3+ , Dy 3+ and Sm 3+ ) doped K 4 Ca(PO 4 ) 2 phosphor were successfully investigated using a conventional high-temperature solid-state reaction. In the near infrared (NIR) range, Ce 3+ -doped K 4 Ca(PO 4 ) 2 phosphor exhibited a UV-Vis. emission band, whereas K 4 Ca(PO 4 ) 2 :Dy 3+ exhibited characteristic emission bands centred at 481 and 576 nm in the near-ultraviolet excitation range. The possibility of ET from Ce 3+ to Dy 3+ in K 4 Ca(PO 4 ) 2 phosphor was confirmed by a significant increase in the photoluminescence intensity of the Dy 3+ ion based on the spectral overlap of acceptor and donor ions. X-ray diffraction, Fourier-transform infrared and thermogravimetric analysis/differential thermal analysis TGA/DTA were carried out to study phase purity, presence of functional groups and amount of weight loss under different temperature regimes. Therefore, the RE 3+ -doped K 4 Ca(PO 4 ) 2 phosphor may be a stable phosphor host for light-emitting diode applications., (© 2023 John Wiley & Sons Ltd.)

This article focuses on the effect of monovalent cation doping on the optical properties of rare earth (RE = Eu 3+ , Tb 3+ ) co-doped Ca 14 Zn 6 Al 10 O 35 which has been synthesized by a low temperature combustion method. Crystalline phase of the Ca 14 Zn 6 Al 10 O 35 phosphor was examined and confirmed by X-ray diffraction measurement. Under near-ultraviolet light excitation Eu 3+ -doped Ca 14 Zn 6 Al 10 O 35 phosphor exhibit characterization of Eu 3+ emission bands that are located at a maximum wavelength (λ max ) of approximately 470 nm and other peaks centred at 593 nm and 615 nm, respectively. With Tb 3+ -doped Ca 14 Zn 6 Al 10 O 35 phosphor showing a green emission band centred at 544 nm under near-ultraviolet range. Furthermore, we studied the energy transfer process in Eu 3+ /Tb 3+ pair and enhancement in photoluminescence (PL) intensity with doping different charge compensation. Here we obtained the optimum PL emission intensity of the phosphor in broad and intense visible spectral range which may be significant for the fabrication of white light emitting diodes (WLEDs)., (© 2023 John Wiley & Sons Ltd.)

The Ho 3+ -doped YVO 4 phosphors were successfully prepared via a sol-gel process in which citric acid was used as a chelating agent. X-ray diffraction (XRD) confirmed the effective inclusion of Ho 3+ ions into the host matrix with the formation of single phase YVO 4 . The surface morphology was observed using SEM, the results of which showed a grain growth propensity and the agglomeration of prepared phosphors. The V-O (VO 4 3- ) vibration mode was analyzed through Fourier transform infrared (FTIR) spectra. The spectroscopic properties were reported through UV-vis-NIR diffuse reflectance and photoluminescence (PL) spectra. The Judd-Ofelt (J-O) intensity parameters Ω 2 = 0.03 × 10 -20 cm 2 , Ω 4 = 0.22 × 10 -20 cm 2 , and Ω 6 = 0.23 × 10 -20 cm 2 obtained for the Y 0.97 VO 4 :0.03Ho 3+ phosphors were used to obtain the total transition probabilities ( A T ), radiative lifetimes ( τ rad ) and branching ratios ( β ) for the certain transitions of Ho 3+ ions. Under 310 nm UV excitation, the visible emission spectra were measured, and an intense emission was observed around 541 nm (green region) for all the samples. The emission cross-section σ P ( λ ) was 3.22 × 10 -21 cm 2 and the branching ratio ( β ) was 0.816; these were investigated to capture the optimal concentration of the Y 0.97 VO 4 :0.03Ho 3+ phosphor. The estimated color coordinates were observed in the green region of CIE diagram. Ultimately, the superior properties ( σ P ( λ ), β , and color purity) of Y 0.97 VO 4 :0.03Ho 3+ phosphor may make it suitable for green emitting devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In the present work, a series of Bi 3+ -activated Ca 2 BO 3 Cl phosphors was synthesized using the conventional high-temperature solid-state reaction method. The crystal structure of the prepared sample was determined to be monoclinic with space group P21/c. Scanning electron microscopy (SEM) analysis demonstrated the surface morphology with aggregated particles and sizes in the nano range. The presence of vibrational features and their luminescence characteristics were studied using Fourier transform infrared spectroscopy and photoluminescence (PL) techniques, respectively. At the 486 nm excitation wavelength, the PL spectrum revealed a sharp emission centred at 732 nm that was attributed to the 3 P 1 → 1 S 0 transition of Bi 3+ . The emission spectra exhibited the highest emission intensity at 0.5 mol% Bi 3+ ion concentration, beyond this the emission intensity decreased due to the concentration quenching phenomenon attributed to multipolar interaction. The Commission Internationale de l'éclairage coordinates located at (0.7347, 0.2653) confirmed emission in the deep-red region with a colour purity of 99.98%. The obtained outcomes suggested that the reported material may be a promising candidate as a red-emitting phosphor for w-LEDs and plant growth applications., (© 2022 John Wiley & Sons Ltd.)

Introduction: Prostate cancer is one of the most common malignant tumors in men and is usually treated with advanced intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). Significant uncorrected interfractional 6-Dimensional setup errors could impact the delivered dose. The aim of this study was to assess the dosimetric impact of 6D interfractional setup errors in hypofractionated prostate cancer using daily kilovoltage cone-beam computed tomography (kV-CBCT)., Methods: This retrospective study comprised twenty prostate cancer patients treated with hypofractionated IMRT (8) and VMAT (12) with daily kV-CBCT image guidance. Interfraction 6D setup errors along lateral, longitudinal, vertical, pitch, roll, and yaw axes were evaluated for 400 CBCTs. For targets and organs at risk (OARs), the dosimetric impact of rotational error (R Error ), translational error (T Error ), and translational plus rotational error (T+R Error ) were evaluated on kV-CBCT images., Results: The single fraction maximum T Error ranged from 12-20 mm, and the R Error ranged from 2.8 0 -3.0 0 . The maximum mean absolute dose variation ΔD in D 98% (dose to 98% volume) of CTV-55 and PTV-55 was -0.66±0.82 and -5.94±3.8 Gy, respectively, in the T+R Error . The maximum ΔD (%) for D 98% and D 0.035cc in CTV-55 was -4.29% and 2.49%, respectively, while in PTV-55 it was -24.9% and 2.36%. The mean dose reduction for D 98% in CTV-55 and D 98% and D 95% in PTV-55 was statistically significant (p<0.05) for T Error and T+R Error . The mean dose variation for D mean and D 50% in the rectum was statistically significant (p<0.05) for T Error and T+R Error ., Conclusion: The uncorrected interfractional 6D setup error results in significant target underdosing and OAR overdosing in prostate cancer. This emphasizes the need to correct interfractional 6D setup errors daily in IMRT and VMAT., (Copyright © 2022. Published by Elsevier Inc.)

Borochlorate phosphors have shown their worth in modern day lighting over the last few years. Colour tunability of the phosphor is a modern techniques used to obtain white-light-emitting diodes (WLEDs). In the proposed work, Sm 3+ ,Eu 2+ -activated/co-activated Ba 2 AlB 4 O 7 Cl phosphors were investigated for WLED applications as well as display devices. A convectional solid-state diffusion method was used to synthesize the proposed phosphors. X-ray diffraction (XRD) of the proposed phosphors confirmed the crystalline nature of the sample. Morphological studies on the samples were carried out using scanning electron microscopy analysis. A photoluminescence study of the colour tunable phosphor showed the characteristic peak of Sm 3+ together with one broad peak for Eu 2+ ions. Red to blue colour tunability was observed in the proposed phosphor with enhancement of Eu 2+ ions. All these results showed the worth of this sample in WLED applications as well as in display devices., (© 2022 John Wiley & Sons Ltd.)

Aluminate-based phosphors have been the most investigated luminescent phosphors over decades due to their outstanding optical properties. In the proposed work, a series of Sm 3+ -doped Ca 8.25 Na 1.5 Al 6 O 18 (CNAO) phosphor sample was prepared using a simple combustion technique with the help of two fuels i.e., urea-glycine. The purity of phase and structural analysis of the CNAO phosphors were confirmed using X-ray diffraction analysis. Vibrational features of this phosphors confirmed were via Fourier transform infrared analysis. A photoluminescence study of this phosphor showed a doublet emission at 568 and 576 nm in the yellow region attributable to the 4 G 5/2 → 6 H 5/2 transition of Sm 3+ ions, whereas a doublet peak noticed in red region ranged from 600 to 620 nm and was attributable to the 4 G 5/2 → 6 H 7/2 transition of Sm 3+ ions. Moreover, Commission Internationale de l'éclairage colour coordinates were also located in the yellowish-red region and confirmed the potential of this phosphor as a yellowish-red component for white light-emitting diodes and display devices applications., (© 2022 John Wiley & Sons Ltd.)

Different concentrations of rare earth Sm 3+ - and Dy 3+ -activated MgCaAl 10 O 17 phosphors were synthesized using the combustion route and their detailed luminescence investigations are reported in this paper. The photoluminescence excitation spectra of Sm 3+ - and Dy 3+ -activated MgCaAl 10 O 17 phosphor show multiple peaks in the ultraviolet light region of the electromagnetic spectrum. The characteristic emission spectra of the MgCaAl 10 O 17 :Sm 3+ phosphor are located at 563 nm, 594 nm, and 644 nm, with the maximum emission intensity occurring at 594 nm. The emission spectra of the MgCaAl 10 O 17 :Dy 3+ phosphor show two emission peaks, one at 476 nm wavelength in the blue light region and the other at 573 nm wavelength in the yellow region. The above results suggest that the prepared phosphor can be suitable for applications in eco-friendly solid-state lighting., (© 2022 John Wiley & Sons Ltd.)

The synthesis of BiPO 4 :Eu 3+ phosphors has been achieved via a wet chemical process. X-ray diffraction patterns show that the phase of the as-prepared samples matches very well with the standard BiPO 4 structure. At 395 nm, the highest excitation intensity was observed. Following 395 nm excitation, two characteristic emission peaks at 592 nm and 616 nm were shown. At 0.5 mol% of Eu 3+ ions, concentration quenching occurred. The particle size is within the micrometre range, according to the scanning electron microscope magnification. The chromaticity coordinates for wavelengths 592 nm and 616 nm are (x = 0.586, y = 0.412) and (x = 0.682, y = 0.317), respectively. The findings imply that the prepared phosphor may be used to create white light-emitting diodes., (© 2022 John Wiley & Sons Ltd.)

Pyrochlore phosphors have shown their worth in modern day lighting in the last few years. Colour tunability of the phosphor is one of the modern techniques used to obtain white light-emitting diodes (WLEDs). In the proposed work, Y 2 Zr 2 O 7 :Sm 3+ ,Eu 3+ phosphors were investigated for WLED applications as well as display devices. A convectional solid-state diffusion method was used to synthesize the proposed phosphors. X-ray diffraction of the proposed phosphors was performed and compared with the standard Inorganic Crystal Structure Database. The crystal structure of the sample was cubic in nature, obtained from Rietveld refinement. Vibrational and morphological studies on the samples were carried out using Fourier transform infrared spectroscopy and scanning electron microscopy analysis. The photoluminescence study of the colour tunable phosphor showed the characteristic peak of Sm 3+ together with the two sharp peaks of Eu 3+ ions. Greenish yellow to red colour tunability was observed in the proposed phosphor with enhancement of Eu 3+ ions. All these results showed the worth of this sample for WLEDs applications as well as in display devices., (© 2022 John Wiley & Sons Ltd.)

This work presents the optimized luminescence spectra for the Ce 3+ ,Sm 3+ -doped NaSrPO 4 phosphor that was synthesized using a wet chemical method. Ce 3+ and Sm 3+ are activator impurities that show spectral splitting bands that corresponds to the d-f and f-f transitions, respectively. These impurity elements shows the characteristics spectral bands when doped with the NaSrPO 4 host lattice. Spectral splitting in the Ce 3+ excitation band was monitored in the 240-340 nm range, in which the observed bands were located at 269 nm, 292 nm and 321 nm, and emission bands were observed in the broad spectral range 330-430 nm. However, when Sm 3+ ion was doped in the same host lattice we obtained a characteristic emission band at 590 and 645 nm in the orange-red region, under sharp excitation bands located at 345, 361, 375, and 403 nm respectively. Also, we carried out energy transfer analysis in the Ce 3+ /Dy 3+ -doped NaSrPO 4 phosphor. Further crystalline phase and the nanophase nature of the phosphor compound were confirmed using X-ray diffraction and transmission electron microscopy analyses., (© 2022 John Wiley & Sons Ltd.)

Semiconductor assisted photocatalysis is one of the most efficient methods for the degradation of complex organic dyes. A major limiting factor of semiconductor assisted photocatalysis is the requirement of a continuous source of light to perform a redox reaction. One of the upcoming solutions is photon energy-storing long afterglow/persistent phosphors. They are an unusual kind of rechargeable, photon energy capturing/trapping phosphors that can trap charge carriers (electrons/holes) in their meta-stable energy levels, thereby resulting in persistent luminescence. Persistence luminescence from such materials can range from minutes to hours. The coupling of long afterglow phosphors (LAP) with the conventional semiconductor is a promising way to support the photocatalytic process even in dark. In addition, dissimilar band structures of LAPs and semiconductor results in formation of heterojunction which further suppresses the recombination of charge. Such an encouraging idea of LAP for round-the-clock working photocatalytic system is in its premature stage; which is required to be investigated fully. Thus, we present a state-of-art review on the potential materials for assisting round-the-clock photocatalysis, trapping-detrapping mechanism in LAP materials, fabrication strategies and their associated characterization tools. Review also covers LAP materials and their photocatalytic mechanism briefly., (© 2022 IOP Publishing Ltd.)

Purpose: The purpose of this study is to evaluate the dosimetric impact of Hounsfield unit (HU) variations in kilovoltage cone-beam computed tomography (kV-CBCT) based 3D dose calculation accuracy in the treatment planning system and its validation using measured treatment delivery dose (MTDD) derived dose metrics for Volumetric Modulated Arc Therapy (VMAT) and Intensity Modulated Radiotherapy (IMRT) plans in Head and Neck (HN) Cancer., Methods: CBCT dose calculation accuracy was evaluated for 8 VMAT plans on inhomogeneous phantom and 40 VMAT and IMRT plans of HN Cancer patients and validated using ArcCHECK diode array MTDD derived 3D dose metric on CT and CBCT., Results: The mean percentage dose difference between CBCT and CT in TPS (ΔD(CBCT-CT) TPS ) and 3DVH (ΔD(CBCT-CT) 3DVH ) were compared for the corresponding evaluation dose metrics (D 98% , D 95% , D 50% , D 2% , D max , D 1cc , D 0.03cc , D mean ) of all PTVs and OARs in phantom and patients. ΔD(CBCT-CT) TPS and ΔD(CBCT-CT) 3DVH for all evaluation dose points of all PTVs and OARs were less than 2.55% in phantom and 2.4% in HN patients. The Pearson correlation coefficient (r) between ΔD(CBCT-CT) TPS and ΔD(CBCT-CT) 3DVH for all dose points in all PTVs and OARs showed a strong to moderate correlation in phantom and patients with p < 0.001., Conclusions: This study evaluated and validated the potential feasibility of kV-CBCT for treatment plan 3D dose reconstruction in clinical decision making for Adaptive radiotherapy on CT in Head and Neck cancer., (Copyright © 2022 Associazione Italiana di Fisica Medica e Sanitaria. Published by Elsevier Ltd. All rights reserved.)

The article briefly reports the fundamental scientific principles and landmarks in the field of luminescence and further enlightens the importance of persistent phosphor that is now widely used in luminous paints. Its main focus is on phosphorescence that makes use of lanthanides that have gained paramount importance in various cross-sections of luminescent applications. Both inorganic and organic afterglow materials, synthesis and characterization along with skilled researchers' essential updates on emerging trends and efforts are elucidated at length. It exclusively reviews the red/green/blue organic/inorganic/hybrid phosphorescent materials and the latest advances in the development of novel long afterglow materials that can accelerate the green technology in the world of luminescence., (© 2022 John Wiley & Sons, Ltd.)

The present communication is strongly focused on the investigation of synthesis, structural and luminescence properties of cerium (Ce 3+ )- and europium (Eu 3+ )-activated Zn 4 Al 22 O 37 phosphors. Ce 3+ - and Eu 3+ -doped Zn 4 Al 22 O 37 novel phosphors were prepared using a solution combustion synthesis route. Structural properties were studied using powder X-ray diffraction and high-resolution transverse electron microscopy. The optical properties were studied using ultraviolet-visible light spectroscopy and Fourier transform infrared spectroscopy; luminescence properties were studied using a photoluminescence (PL) technique. The crystal structure of the prepared Zn 4 Al 22 O 37 host and Ce 3+ - and Eu 3+ -activated Zn 4 Al 22 O 37 phosphors was investigated and was found to have a hexagonal structure. The measured PL emission spectrum of the Ce 3+ -doped Zn 4 Al 22 O 37 phosphor showed an intense and broad emission band centred at 421 nm under a 298 nm excitation wavelength. By contrast, the Eu 3+ -doped Zn 4 Al 22 O 37 phosphor exhibited two strong and intense emission bands at approximately 594 nm (orange) and 614 nm (red), which were monitored under 395 nm excitation. The Commission Internationale de l'Eclairage (CIE) colour coordinates of the Ce 3+ -doped Zn 4 Al 22 O 37 were investigated and found to be x = 0.1567, y = 0.0637 (blue) at 421 nm and for Eu 3+ -doped Zn 4 Al 22 O 37 were x = 0.6018, y = 0.3976 (orange) at 594 nm and x = 0.6779, y = 0.3219 (red) at 614 nm emission. The luminescence behaviour of the synthesized phosphors suggested that these phosphors may be used in lighting applications., (© 2022 John Wiley & Sons Ltd.)

In the recent few years, Eu 2+ - and Mn 4+ -activated phosphors are widely used as potential colour converters for indoor plant cultivation lighting application due to their marvellous luminescence characteristics as well as low cost. In this investigation, we synthesized novel red colour-emitting Ca (2-x) Mg 2 (SO 4 ) 3 :xmol% Eu 2+ (x = 0-1.0 mol%) phosphors via a solid-state reaction method in a reducing atmosphere. The photoluminescence (PL) excitation spectra of synthesized phosphors exhibited a broad excitation band with three excitation bands peaking at 349 nm, 494 nm, and 554 nm. Under these excitations, emission spectra exhibited a broad band in the red colour region at ~634 nm. The PL emission intensity was measured for different concentrations of Eu 2+ . The maximum Eu 2+ doping concentration in the Ca 2 Mg 2 (SO 4 ) 3 host was observed for 0.5 mol%. According to Dexter theory, it was determined that dipole-dipole interaction was responsible for the concentration quenching. The luminous red colour emission of the sample was confirmed using Commission international de l'eclairage colour coordinates. The results of PL excitation and emission spectra of the prepared phosphors were well matched with excitation and emission wavelengths of phytochrome P R . Therefore, from the entire investigation and obtained results it was concluded that the synthesized Ca 0.995 Mg 2 (SO 4 ) 3 :0.5mol%Eu 2+ phosphor has huge potential for plant cultivation application., (© 2022 John Wiley & Sons Ltd.)

In the current investigation, a series of NaCa 1-x PO 4 :xDy 3+ (x = 0.1, 0.3, 0.5, 0.7, 1.0, 1.5 and 2 mol%) phosphors were synthesized using a solution combustion method and citric acid as fuel. The investigated results from the X-ray diffraction (XRD) pattern showed phase purity of the synthesized material and orthorhombic crystal structure with space group Pna21. Photoluminescence properties of the synthesized phosphors were investigated. The synthesized Dy 3+ -activated phosphor displayed blue (482 nm) and yellow (576 nm) emission under near-ultraviolet or blue excitations. These emission bands were ascribed due to the 4 F 9/2 → 6 H 15/2 and 4 F 9/2 → 6 H 13/2 transitions of Dy 3+ ions. Commission International de l'Eclairage chromaticity coordinates showed emission in the near-white region for the proposed phosphors under different excitations. In addition, the current-voltage (I-V) characteristics of the NaCa 1-x PO 4 :xDy 3+ (x = 1.5 mol%) phosphor-coated silicon solar cell and an uncoated solar cell were investigated under a solar simulator. The I-V characteristics of the proposed phosphor-coated silicon solar cell showed enhancement in solar cell efficiency by ~7.92%. The entire studies and their outcomes showed that synthesized phosphors have potential as white light emitting diodes and for solar applications., (© 2021 John Wiley & Sons Ltd.)

A trivalent Dy 3+ -activated K 3 Ca 2 (SO 4 ) 3 F fluoride-based phosphor was synthesized using a solid-state reaction method and characterized for its thermoluminescence (TL) application. The crystal structure and surface morphology of the as-synthesized material was analyzed using X-ray diffraction and scanning electron microscopy. A series of the K 3 Ca 2 (SO 4 ) 3 F:Dy 3+ phosphor was irradiated using γ-rays from a 60 Co source and TL glow curves were recorded using a Nucleonix 1009I TL reader. The glow curve of the prepared phosphor showed a prominent single peak at 278°C. TL characteristics were maximum intensity at 1 mol% of Dy 3+ ion with a single TL glow peak. The TL glow curve revealed linearity with increase in exposure dose range from 0.1 kGy to 3.0 kGy. Theoretical analysis of the TL glow curve of the γ-ray-irradiated sample was carried out using a computerized glow curve deconvolution method and trapping parameters such as activation energy and frequency factor were calculated using the initial rise method and Ilich's method. The synthesized Dy 3+ -doped K 3 Ca 2 (SO 4 ) 3 phosphor revealed excellent TL properties and was found to be a potential candidate for dosimetric applications., (© 2020 John Wiley & Sons, Ltd.)

In the present study, the thermoluminescence (TL) properties of an Eu 3+ -doped CaNa 2 (SO 4 ) 2 phosphor were studied. The Eu 3+ -doped CaNa 2 (SO 4 ) 2 phosphor was synthesized using the combustion method. The samples were well crystallized in the monoclinic phase. The TL glow curve of the Eu 3+ -doped CaNa 2 (SO 4 ) 2 phosphor showed a single prominent peak at around 210°C with showed linearity on increasing exposure. The response curve of the synthesized phosphor showed linearity in the range 500-7000 Gy. Trapping parameters of synthesized phosphors such as activation energy, frequency factor, and order of kinetics were calculated in the study. These trapping parameters were determined by different methods such as Chen's peak method, the initial rise method, and Ilich's method. Each characteristic of these outcomes demonstrated that the synthesized Eu 3+ -doped CaNa 2 (SO 4 ) 2 phosphor had outstanding TL properties and might be valuable for TL dosimetry application., (© 2020 John Wiley & Sons, Ltd.)

A Eu 3+ -activated Ca 7 Mg 2 (PO 4 ) 6 phosphor was prepared at high temperature (800°C) using a solid-state reaction method. The crystal structure, phase formation of the prepared phosphor was characterized using X-ray diffraction patterns and Fourier transformed infrared analysis. The luminescence properties of the synthesized phosphor were characterized using photoluminescence and thermoluminescence techniques. The prepared phosphor showed two emission peaks at 594 nm with an orange colour due to the 5 D 0 → 7 F 1 transition and at 612 nm a red colour due to the 5 D 0 → 7 F 2 transition under 396 nm near-UV excitation. The prepared phosphors were irradiated with different doses of γ-rays from a 60 Co gamma irradiation source. Thermoluminescence glow curves for this sample phosphor were obtained using a Nucleonix 1009I TL reader. Synthesized phosphor samples were exposed to a 3.6 kGy dose of γ-rays. The thermoluminescence glow curve of the Ca 7 Mg 2 (PO 4 ) 6 :0.05 mol%Eu 3+ phosphor showed maximum intensity at all concentrations of Eu 3+ ions. The Ca 7 Mg 2 (PO 4 ) 6 :0.05 mol%Eu 3+ phosphor was irradiated with different doses of 60 Co γ-irradiation and a linear response was observed between 0.6 kGy and 3.6 kGy. Trapping parameters such as activation energy, frequency factor and order of kinetics were calculated. The CIE chromaticity diagram showed the colour coordinates of the synthesized phosphor in the orange and red regions of the visible spectrum; this spectral feature revealed high colour purity and excellent chromaticity coordinate characteristics. Photoluminescence and thermoluminescence properties revealed that the prepared phosphor could be a potential red-emitting phosphor for eco-friendly white light generation and an excellent thermoluminescent dosimeter material for thermoluminescence dosimetric applications., (© 2020 John Wiley & Sons, Ltd.)

A BaY 2 F 8 :Yb 3+ ,Ho 3+ phosphor was synthesized using a simple precipitation method. The temperature-sensing properties of BaY 2 F 8 :Yb 3+ ,Ho 3+ phosphor were investigated using the fluorescence intensity ratio (FIR) of the thermally coupled energy levels ( 5 F 4 and 5 S 2 ) of Ho 3+ . Energy transitions 5 F 4 → 5 I 8 and 5 S 2 → 5 I 8 gave rise to emission peaks at 538 nm and 549 nm, respectively. The areas under these two emission peaks were used to calculate the FIR. Temperature-dependent upconversion luminescence was recorded in the temperature range 303-623 K using a 980 nm laser excitation source. The results suggested that the BaY 2 F 8 :Yb 3+ , Ho 3+ phosphor has the potential to be used as a non-contact optical temperature sensor., (© 2020 John Wiley & Sons, Ltd.)