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This article reports the characteristics of thermoluminescence (TL) dosimeter of dysprosium doped strontium borate glass for NaO, Li2O, and CaO modifiers imposed by 10–90 Gy dose of 60Co gamma ray irradiation. The different elements are (70.0 – x) B2O3–20SrO–10NaO–xDy2O3, 10Li2O–20SrO–(70 – x)B2O3–(x)Dy2O3 and 10CaO–20SrO–(70.0 – x)B2O3–(x)Dy2O3 (x = 0, 0.10, 0.30, 0.50, 0.70 mol %). The glass was formed by melt quenching method and the ranges of Dy2O3 were 0.0 to 0.7 mol %. Calcium strontium borate doped with 0.3 mol % Dy2O3 shows very good linearity on dose response and gives an excellent sensitivity at 50 Gy dose of 60Co gamma ray irradiation. The samples N1, L1, C3 were completely amorphous. The optimums anneal temperature, time, concentration of Dy2O3 and heating rate were investigated for glass samples N1, L1, C3. The systematic characteristics of glow curve, TL intensity, reproducibility, sensitivity, kinetic parameters and effective atomic number were studied for three selected samples. All samples show the maximum peak from 154–200°C temperatures. [ABSTRACT FROM AUTHOR]

We report the improved dosimetric properties and kinetic parameters of a newly synthesized strontium/ copper co-doped lithium borate glass composition (LB:Sr,Cu). Co-dopants concentration dependent glow curve shape, Thermoluminescence (TL) sensitivity, TL dose response, minimum detectable dose, fading and reproducibility, annealing, order of kinetics, activation energy, and frequency factors are determined. Proposed dosimeter exhibited simple glow curve, good linearity in the dose range of 0.5–4, 1–10 and 10–100 Gy (Co-60 gamma irradiation), easy annealing attributes, excellent reproducibility, and minimal fading. These attractive features of the prepared glass composition are prospective for radiation dosimetry applications. [ABSTRACT FROM AUTHOR]

Composition optimization is essential for achieving improved properties of strontium (Sr 2+ ) doped lithium borate (LSBO) glass. Glasses with compositions (85− x )H 3 BO 3 +15Li 2 CO 3 + x SrCO 3 , where x = 0.5–2.5 mol% are synthesized via melt quenching technique. Glasses are characterized to determine Sr 2+ ions concentration dependent improvements in the structural, physical, and optical properties. XRD patterns verifies the amorphous nature, FESEM images reveals transmitting surface morphology, stable glasses with Hurby parameter ∼0.5 are achieved. FTIR spectra revealed three fundamental peaks around 700.55–930.68 and 1072.07 cm −1 , which corresponded to the trigonal and tetrahedral stretching vibrations of BO 3 and BO 4 units. These peaks are shifted with the increase of modifier concentration. Energy for Urbach tail, direct and indirect optical gaps are calculated. The increasing glass refractive index from 2.34 to 3.00 is ascribed to the conversion of BO 4 into BO 3 units. Emission spectra exhibit three peaks centered at 492.65, 536 and 549 nm, corresponding to the transitions from the 1 D 2 , 3 D 3 and 3 D 2 levels to ground state 1 S 0 respectively, and accompanied by a slight blueshift attributed to the formation of new complexes. Effects of strontium ion contents on the structural and optical properties are demonstrated. Our observation may contribute towards the development of LSBO based glass photonics. [ABSTRACT FROM AUTHOR]

This study addresses the characteristics of Cu-doped and undoped potassium borate glass for use as ionizing radiation dosimeters by investigating and comparing the thermoluminescence responses, linearity, sensitivity and dose response s of the two types of glasses. A number of samples based on xK CO + (100 - x)H BO , where 10 ≤ x ≤ 30 mol.%, have been prepared using a melt quenching technique. The amorphous phases were identified using X-ray diffraction (XRD). The undoped potassium borate samples 20K CO + 80H BO (mol.%) and Cu-doped (0.5 mol.%) samples were placed in a solid phantom apparatus and irradiated with in X-ray tube under 6 MV accelerating voltage with doses ranging from 0.5 to 4.0 Gy. This beam was produced by the Primus MLC 3339 linear accelerator (LINAC) available at Hospital Sultan Ismail, Johor Bahru, Malaysia. The results clearly show the superiority of Cu-doped glass in terms of response and sensitivity to producing luminescence over undoped potassium borate glass. The sensitivity of Cu-doped glass is 6.75 times greater than that of undoped glass. [ABSTRACT FROM AUTHOR]

The effect of dysprosium ion (Dy3+) on the optical absorption and band gap energy of strontium borate glass systems prepared by melt quenching technique have been reported. The results show that the broad absorption edge of doped glasses shifts back and forth as a function of Dy2O3 concentrations. The intensities of five prominent and two weak optical transitions change accordingly with Dy2O3 concentrations. The defect centres are induced with the presence of Dy3+ ions in glass samples. This attributes to the intra-configurational (f-f) transitions of Dy3+ ions in glass network. In addition, the decreasing trend of optical band gap energy and Urbach energy can be related to defect centres created by Dy3+ ions. The FTIR study reveals the presence of BO3, BO4 vibration groups and the bending of B-O-B units. The asymmetric stretching of BO3 and BO4 was apparent at higher Dy2O3 concentrations. More tetrahedral BO4 units were formed by increasing Dy2O3 concentrations. The dependency of Dy2O3 concentrations on the optical properties is further discussed with other important physical properties. [ABSTRACT FROM AUTHOR]

Germanium doped calcium borate glasses are investigated in term of thermoluminescence properties to seek their possibility to use as glass radiation dosimeter. The samples were exposed to 6 MV, and 10 MV photon beams in a dose range of 0.5–4.0 Gy. There is a single and broad thermoluminescence glow curve that exhibits its maximum intensity at about 300 °C. Linear dose response behavior has been found in this dose range for the both photon energies. Effective atomic number, TL sensitivity, and reproducibility have also been studied. It is found that the sensitivity of germanium doped sample at 6 MV is only 1.28% and it is superior to the sensitivity at 10 MV. The reproducibility of germanium doped sample is good with a percentage of relative error less than 10%. The results indicate that this glass has a potential to be used as a radiation dosimetry, especially for application in radiotherapy. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to investigate the thermoluminescence properties of germanium doped calcium borate glass for thermoluminescence dosimeter used. Glasses with composition (30−x) CaO–70B2O3: xGeO2 where x=0.1, 0.2, 0.3, 0.4 and 0.5mol% were prepared using a melt-quenching method. The glasses were irradiated to 60Co gamma ray with doses ranging from 0.5Gy to 4.0Gy. The amorphous phases were identified for all glass samples. The glow curves were analyzed to determine various characterizations of a thermoluminescence dosimeter of the glass. It was found that the sample with a concentration of 0.1mol% GeO2 has the best thermoluminescence characteristics such as linearity, sensitivity, fading characteristic, minimum detectable dose and effective atomic number. The results clearly showed that germanium doped calcium borate glass has a potential to be considered as the thermoluminescence dosimeter. [Copyright &y& Elsevier]

Abstract: Characteristics of lithium potassium borate glasses with various copper concentrations are reported. The glasses were prepared by the melt quenching method and irradiated with photons to doses in the 0.5–4.0Gy range. Glowing curves, dose response curves, reproducibility of the response, dose threshold, thermal fading and optical bleaching were studied. [Copyright &y& Elsevier]

Copper-doped (0.5 mol%) and undoped potassium borate glasses have been prepared by the composition of (100-x)H3BO3 + xK2CO3, where 10 ⩽ x ⩽ 30 mol % by the traditional melting quenching method. The structural pattern of glasses with different composition has been identified by X-ray diffraction (XRD). The glow curves were analysed to determine various characterizations of the TLDs. Identification of the compositions and concentrations and effective atomic number of undoped and doped potassium borate glass was carried out using scanning electron microscope analysis (SEM). The dopant concentrations are found to be 0.25mol%, while Zeff are 11.42 and 10.48 for Cu-doped and undoped potassium borate glasses, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The co-doped SnO2 nanoparticles of lithium potassium borate doped with Cu glass were prepared using the chemical quenching technique. The X-ray diffraction analysis revealed the amorphous nature of the sample. The morphology was determined using high resolution scanning electron microscopy (FE-SEM). The photoluminescence properties and energy band gaps of the glass were investigated. The changes in the energy band gap were due to the concentration of SnO2 nanoparticles and copper ions. An enhancement of almost three times was shown when SnO2 nanoparticles were added as co-dopants to 0.1mol% of Cu and the peak shapes shifted from blue luminescence to blue and green luminescence. [Copyright &y& Elsevier]

The aim of this study is to prepare and investigate the thermoluminescence characteristics for the un-doped and Cu 2 O doped calcium lithium borate glass upon adding various Cu 2 O concentrations of 0.005% to 0.1 mol%. The glasses were prepared by melt quenching method and irradiated with 60 CO gamma-ray having different doses in the range of (0.5–4) Gy, (5–10) Gy, and (20–100) Gy. The amorphous phases were identified for optimization glass samples, effect of heating rate, glowing curves, linearity, sensitivity, fading, reproducibility of response and minimum detectable dose are also studied. The TL sample with 0.02 mol% Cu 2 O concentration has higher response compared to the other samples concentration for a delivered dose of 50 Gy, The recorded glow curves consist a dominant peak at 187 °C for a heating rate of 5 °C s −1 . However, the value of effective atomic number Z eff is 8.84 for 0.02Cu 2 O doped which are near to the atomic number of soft tissue. [ABSTRACT FROM AUTHOR]

Optimizing the concentration of host borate glass system to achieve a superior thermal and structural stability is challenging for sundry applications. A series of lithium strontium borate (LSBO) glasses with composition of (85 − x ) H 3 BO 3 − 15Li 2 CO 3 − x SrCO 3, where x = 5, 7.5, 10, 12.5 and 15 mol% are prepared via melt quenching technique. Synthesized glasses are thoroughly characterized using XRD, FTIR, DTA, FESEM, PL, and UV–vis-NIR measurements to determine the influence of strontium (Sr 2 + ) ion concentration on thermal, physical, and structural properties of the glasses. XRD pattern confirms the amorphous nature of all samples. The FESEM images verify their homogeneous and transmitting surface morphology. Physical properties are determined in terms of glass density, molar volume, molar refractivity, polaron radius, inter-nuclear distance, field-strength, and ion concentration. Glass density is found to increase from 2.53 to 2.95 g/cm 3 with increasing Sr 2 + ion contents. FTIR spectra exhibit the presence of two fundamental peaks in the range of 700–1070 cm − 1 corresponding to the trigonal and tetrahedral stretching vibrations of BO 3 and BO 4 units. These peaks show a shift with the increase of modifier concentration. DTA results display peaks for glass transition, crystallization and melting at 500, 600 and 900 °C, respectively. Prepared samples are highly stable with Hurby parameter ~ 0.5. The direct, indirect band gap and Urbach energy calculated from the absorption edge of UV–vis-NIR spectra lie within 3.4–3.8 eV and 3.84–3.93 eV, 3.84–3.25 eV, respectively. The observed increase in refractive index from 2.17–2.19 is ascribed to the conversion of BO 4 into BO 3 units. Room temperature PL spectra under 430 nm excitations display two peaks centered at 482 and 526 nm accompanied by slight peak shift towards the lower wavelength due to the formation of new complexes in the glass network. Results are analyzed via different mechanism and compared. Excellent features of the results nominate these compositions potential for solid state lasers, photonic devices, and optical fibers applications. [ABSTRACT FROM AUTHOR]