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This work presents the structural impacts of the crystalline micro and nanoparticles co-doped aluminum oxide on their thermoluminescent features. For this purpose, Ca9Al (PO4)7 with different Cr and Si concentrations was prepared and the best in TL-response in this batch was selected for further study which was Ca9Al (PO4)7: 2 Cr, 8 Si mol%. Additionally, Al2O3 co-doped with different dopants was synthesized. Al2O3: 0.005 (P, Ca, Cr, Si) mol% showed the higher TL-response in this batch and was selected for further study. The surface morphology and uniform distribution of the elements of the selected samples were confirmed using scanning electron microscopy (SEM) with Energy Dispersive X-ray scattering (EDX) analysis. X-Ray Diffraction (XRD) and transmission electron microscope (TEM) results reflected the existence of the nanoparticles structure with average sizes of 22.7 and 35.13 nm for Ca9Al (PO4)7: 2 Cr, 8 Si mol% and Al2O3: 0.005 (P, Ca, Cr, Si) mol%, respectively. Photoluminescence (PL) spectrum at λex = 304 nm shows emission at range of 370–600 nm and at 825 nm for both samples. Good linear dose-response relationships were found in dose range of 3 up to 20 Gy. But, the TL-response of Al2O3: 0.005 (P, Ca, Cr, Si) mol% structure was about 22 times higher than that of the Ca9Al (PO4)7: 2 Cr, 8 Si mol% one. Therefore, introducing P and Ca as a co-dopants with Cr and Si in Al2O3: P, Ca, Cr, Si highly increased its TL-response. This reflected the structural dependence of the studied samples on their TL-responses.

Gamma radiation, neutrons, protons, and alphas particles shielding competences for gallium germanate-tellurite (GeO2.TeO2.Ga2O3) glasses doped with Pr6O11 were tested. The investigated glasses were named as GTGPr1, GTGPr2, GTGPr3, and GTGPr4. Mass attenuation coefficients (MAC) for the proposed glasses were calculated utilizing Phy-X/PSD program and simulated by MCNP5 simulation codes in the photon energy range of 0.015–15 MeV. With the help of MAC values, the linear attenuation coefficient (LAC), half value layer (HVL), mean free path (MFP), and effective atomic number (Zeff) were calculated. Moreover, the absorbed dose received from 137Cs with activity 10 μCi was calculated in presence of the studied glasses. Buildup factors (BUFs) include exposure buildup factor (EBF), and energy absorption buildup factor (EABF) for all investigated glasses were also calculated. Results reflected that the GTGPr4 glass has the highest MAC, LAC values and lowest HVL among other selected germanate glasses. The values of Zeff were around 0.04 MeV varied between 43.07 and 48.19, while at 1.5 MeV were between 18.70 and 21.25. The GTGPr1 possesses the highest values of BUFs around the studied range of energy, while GTGPr4 glasses possesses the lowest values. Moreover, the fast neutron removal cross section was (ΣR = 0.02151 and 0.01942 cm2 g−1) for GTGPr1 and GTGPr4, respectively. The investigated glasses can be useful to construct superior radiation shielding materials to use in nuclear medicine applications.

Glass samples of titanium-lead bismuth borate with the composition of (60B2O3 – 20Bi2O3 – (20-x)PbO – xTiO2), where 0 ≤ x ≤ 10 wt% labeled as BBPT0.0 (x = 0) to BBPT10.0 (x = 10) were synthesized. The melt quenching technique was used in the preparation. The amorphous character and vibrational groups for all samples were confirmed through XRD and FTIR measurements, respectively. The optical band gap (Eopt), Urbach's energy (Eurbach), and the optical dispersion constants have been determined using UV–Vis spectra. Results reveal that the values of the optical band gap energy exhibit a decrease with the TiO2 concentration, in contrast with Urbach's energy which displays a linear increase from 0.43 to 0.64 eV. In addition, the values of single-oscillator energy (Eo) has the same behavior of the optical energy gap (Eopt), while the dispersion energy parameter (Ed) has an inversely behavior. Mass attenuation coefficients (μ/ρ) of the investigated glasses have been computed using the Geant4 simulation toolkit and WinXCOM database software. Geant4 model of a HPGe detector has been employed to perform the Monte Carlo simulations for the glass samples with five thicknesses from 1 to 3 cm at the gamma ray energies in the range of 356–2510 keV. The transmission fractions as a function of the thickness at 356 keV photon energy for all studied glasses has been performed. Half value layer (HVL) was derived from the μ/ρ values. Results showed the studied glasses have good shielding capability according to their mass attenuation coefficients, transmission fractions and HVL values.

In this work, we examine a fractional-order model for simulating the spread of the monkeypox virus in the human host and rodent populations. The employment of the fractional form of the model gives a better insight into the dynamics and spread of the virus, which will help in providing some new control measures. The model is formulated into eight mutually exclusive compartments and the form of a nonlinear system of differential equations. The reproduction number for the present epidemic system is found. In addition, the equilibrium points of the model are investigated and the associated stability analysis is carried out. The influences of key parameters in the model and the ways to control the monkeypox epidemic have been thoroughly examined for the fractional model. To ensure that the model accurately simulates the nonlinear phenomenon, we adapt an efficient numerical technique to solve the presented model, and the acquired results reveal the dynamic behaviors of the model. It is observed that when memory influences are considered for the present model, through Caputo fractional-order derivatives, they affect the speed and time taken by solution trajectories towards steady-state equilibria.

Transparent thermoluminescent alumino-phosphate‑sodium glass system of 15Al2O3-35P2O5-25CaO-25Na2CO3 (all in mol%) doped with different concentrations of SiO2 were prepared by conventional melt quenching technique. X-ray diffraction (XRD) studies checked the amorphous nature of the prepared glass. Fourier Transform Infrared (FTIR) of the glass system was investigated to find the effect of SiO2-dopant concentrations on the absorption spectra in comparison with that of bulk sample (without dopants). Direct and indirect energy band gaps (Eopt) were determined and found to be in the range of 2.47–3.65 eV for m = ½ and 2.24–3.3 eV for m = 2. Refractive index (n) for each Eopt value vary from 2.42 to 2.55 and from 2.32 to 2.63 for the direct and indirect transition, respectively. Urbach energy values of the newly prepared glasses are found to be from 0.57 to 0.98 eV. In addition, effect of UV exposure on thermoluminescence (TL) sensitivity was also examined for APCNSi5 (contains 500 ppm SiO2 concentration) and a linear response to dose was obtained, indicating that this type of glass is promising as a TL dosimeter within the UV range.

Si-doped Na5Ca2AlP4O16 nanophosphor was prepared using sol-gel method and then characterized by both X-ray diffraction (XRD) and transmission electron microscope (TEM). The distribution uniformity of the associate elements was confirmed using SEM-EDX mapping. A comparative dosimetric study between this prepared sample and a glass system based on aluminum oxide with the same constituents [(500 ppm Si-doped 15Al2O3-35 P2O5–25CaO–25Na2CO3, in mol. % (abbreviated by APCNSi5)] was achieved. The effective atomic number (Zeff) of both matrices were calculated and found to be 10.6 and 11 for nanophosphor and APCNSi5 samples, respectively. Both values approached that of natural bone. The Energy Dependence (ED) of the two samples was calculated and the nanophosphor sample behaved much better, specially in the energy range 0.1–20 MeV. Thermoluminescent (TL) response of the Na5Ca2AlP4O16: Si4+ nanophosphor is found to be 2.52 times that of glass system APCNSi5. TL property study of prepared samples showed that nanostructure sample had an excellent dose-response linearity up to 40 Gy γ-doses, while linearity up to only 20 Gy was recorded with APCNSi5 sample. In addition, the minimum detectable dose values (MDDs) were found to be 0.05 and 6 mGy for Na5Ca2AlP4O16: Si4+ and APCNSi5 samples, respectively. The important features of the work presented herein are that an efficient good dosimeter depends mainly on: (a) careful choice of its constituents (b) the recognition of the processes that underlie the formation of its particular structures.

The optical, Raman and Photoluminescence properties of Makrofol DE 6-2 polycarbonates were explored in detail. A set of polymeric Makrofol samples were subjected to γ-ray source at various doses ranging between 1 and 200 kGy. UV–Vis spectra depicted that Makrofol DE 6-2 has a high absorption maximum band at about 230 nm and decreases sharply at about 285 nm. The optical energy band gap was calculated using different methods, Ineffective Thickness Method (ITM), Derivation of Ineffective Thickness Method (DITM), Absorption Spectrum Fitting (ASF) and Derivation of Absorption Spectrum Fitting (DASF) methods. All used methods revealed an observable decrease in the optical energy band gap values with increasing gamma irradiation doses for both the indirect and direct transitions, whereas the refractive index showed the reverse trend. Also, the photoluminescence intensity decreases with increasing gamma dose up to 200 kGy due to formation of defects. Peaks at 884, 1364, 1394 and 1854 cm−1 are registered corroborative its structure in the Raman spectrum. Its intensity showed a decrease with increasing the gamma dose which may be attributed to the formation of non-irradiative levels as a result of degradation. Color change of the polymer from transparent to faint yellowish after γ-irradiation of doses higher than 1 kGy was observed which may be due to formation of color centers appeared in the range 305–315 nm. The present results should be taken into account before utilization of Makrofol DE 6–2 in photoelectric devices and medical applications related to gamma radiation.