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This paper includes a comprehensive analysis of the radiation shielding, optical properties, and structural makeup of polymer composites that contain Dy 2 O 3 additions. XRD-pattern investigates the effect of loading Dy 2 O 3 content on PS, with the average crystallite size of Dy 2 O 3 decreases from 39 nm to 30 nm as Dy 2 O 3 increases from 2.5 to 7.5 wt% in the PS matrix. The optical properties of the nanocomposites showed that with the increase in the Dy 2 O 3 content, the transmittance, as well as the direct and indirect band gap, decreased. The E g Indirect bandgap decreased from 3.1 to 2.75 eV with a Dy 2 O 3 increase from 0 to 7.5 wt%, while the E g direct Bandgap reduced from 4.6 to 4.35 eV. While the Urbach energy Eu and the refractive index increase, Eu rises from 0.48 to 0.60 e V, and n improves from 1.4 to 1.78 from 0 to 7.5 wt%. In order to conduct an accurate analysis of the gamma-ray attenuation capabilities of the selected new polymer composites, these composites were manufactured with varying proportions of the additive components. With the assistance of a Na(Tl) detector, experimental assessments were carried out on the gamma rays throughout a broad spectrum of photon energies, ranging from 81 keV up to 1416 keV. The sample encased in PS/Dy7.5 demonstrates excellent radiation attenuation, and it is important to note that this novel polymer shielding material does not include any hazardous components. • "Dy2O3 in PS enhances radiation shielding". • "Increased Dy2O3 reduces PS's transmittance". • "Dy2O3 addition lowers bandgap energy". • "Higher Dy2O3 increases refractive index". • "Dy2O3/PS composites ideal for radiation protection". [ABSTRACT FROM AUTHOR]

Tellurite glass is a model material having superior features for several applications. It can be considered as a potential host matrix for different oxides, and this paper aims to study the effects of TeO 2 /B 2 O 3 substitution on synthesis, physical, optical and radiation shielding properties of ZnO–Li 2 O-GeO 2 -Bi 2 O 3 glasses produced by melt quenching technique. The physical and optical features of the fabricated glasses were experimentally investigated by determining pivotal parameters such as density, XRD, tellurium ion concentration (N i), linear refractive index (n o), polaron radius (r p) and inter nuclear distance (r i). Moreover, the relative radiation deposition within the glasses was assessed via the attenuation coefficients (e.g. MAC), specific gamma ray constant (ᴦ), total stopping power (TSP), neutron cross sections, and dose rate (D). Our results suggest that both TeO 2 and B 2 O 3 additives have a significant effect on the fundamental properties of the ZnO–Li 2 O-GeO 2 -Bi 2 O 3 glasses. It also found that the lower thicknesses of the present glasses are required to provide the same level of shielding than ordinary, ilmenite, steel scrap, hematic-serpentine, ilmenite-limonite and basalt-magnetite concretes, RS253-G18 and RS360 glass shields. Therefore, presently investigated glasses are promising photon shields in different technological applications of gamma- and x-rays. [ABSTRACT FROM AUTHOR]

In this research paper, we studied the optical and nuclear shielding efficiency of newly developed BGO glasses with the following compositions (in wt%): 32Bi 2 O 3 –68GeO 2 , 42Bi 2 O 3 –58GeO 2 , 47Bi 2 O 3 –53GeO 2 , 52Bi 2 O–48GeO 2 , 62Bi 2 O 3 –38GeO 2. BGO glasses were prepared by traditional melt quenching method. To obtain the band gap values of fabricated BGO glasses, optical absorption spectra were used for evaluation of optical properties. The mass attenuation coefficients (μ/ρ) were achieved for prepared glasses at 0.015–15 MeV photon energies employing MCNPX Monte Carlo code and WinXcom program. Moreover, broad-range of nuclear shielding parameters for gamma ray, neutrons and charged particles such as mass attenuation coefficient, half value layer, effective atomic number, buildup factors, mass stopping powers, projected ranges, fast neutron removal cross sections and damage factors were calculated. The refractive index is calculated from E opt , As Bi 2 O 3 concentration is enhanced, E opt is also increased as well as the optical electronegativity and consequently the refractive index. In addition, the results showed that BIGE5 glass sample with highest Bi 2 O 3 contribution has excellent nuclear radiation shielding ability among the other fabricated glass samples. [ABSTRACT FROM AUTHOR]

Cu 2 ZnSnS 4 (CZTS) thin films have been synthesized by spray pyrolysis technique, deposited on glass substrates and then irradiated by high gamma radiations. Six gamma radiation doses have been applied: 10, 20, 30, 40, 50 and 100 kGy. The main objective of this work was to study the physical properties behavior of CZTS thin films under high gamma irradiation. Structural, optical and morphological properties of CZTS thin films were explored by X-ray diffraction, spectrophotometer and Scanning Electron Microscope, respectively. Structural analysis has shown that no noticeable changes have been occurred in the preferred orientation (112) or diffraction angles after gamma irradiation. Nevertheless, a significant increase in crystallite size from 52 to 79 nm has been observed after irradiation with 100 kGy gamma dose, which indicates a clear enhancement in crystalline structure. Certain optical parameters such as absorption and extinction coefficients (α(λ),K(λ)) have been only slightly affected, which indicate a radiation hardness of the CZTS thin films within the ionizing radiation range studied in this paper. Band gap energy of the irradiated thin films have been increased with the irradiation and reached 1.6 eV at 100 kGy gamma dose. Other optical parameters such as refractive index n(λ) and lattice dielectric constant (ε) have been determined and analyzed. All these experimental results clearly showed that structural properties of CZTS films have been improved by gamma irradiation while the optical properties have been slightly changed, which is favorable for optoelectronic applications working near nuclear environments or even for outer space solar cells and instrumentation for high-altitude flight, where gamma radiations are abundant. [ABSTRACT FROM AUTHOR]

The paper describes the effect of high effective atomic number (Z eff) materials loading in polystyrene based thin-film Plastic Scintillators (PS). Thin plastic scintillator sheets have been loaded with high Z materials such as BaFBr:Eu, Gd 2 O 2 S:Tb, Gd 2 O 3 , BaF 2 , CeO 2 and Bi 2 O 3. Polystyrene based PS sheets of 250 ± 50 μ m thickness have been prepared by dissolving predetermined quantities of polystyrene, 2,5-Diphenyloxazole (PPO) and 1,4-bis(5-phenyl-2-oxazolyl) benzene (POPOP) in the p-xylene solvent. High Z eff material powders of 23 μ m size are mixed in the plastic scintillator solution and coated over the cellulose acetate-based transparency sheets. The dried films are peeled off, and their photoluminescence, radioluminescence, pulse height spectrum and response to alpha, beta, gamma and neutron radiations are studied by adopting suitable methods. The high Z eff materials for loading in PS are selected based on their physical properties like refractive index, bandgap, Z eff , Photoluminescence (PL) properties. While the composite scintillator loaded with 14.3 wt% of BaFBr:Eu2+ showed significant increase compare to other high Z materials. The loading concentration has been optimized as 14.3 wt% from the BaFBr:Eu2+ studies. Most of the composite scintillators showed improvement in radioluminescence and pulse height spectra for different radiations. • Polystyrene based thin plastic scintillator have been prepared by solvent-based fabrication method. • Thin composite plastic scintillator are studied with high Z eff material loading. • High Z eff material loaded composite scintillators showed enhanced response to radiation. • BaFBr:Eu loaded composite PS has shown the best promising result. [ABSTRACT FROM AUTHOR]

Poly (methyl methacrylate) (PMMA) is widely used in scientific and industrial applications. Because of its favorable properties, it is used in various fields such as optical, medical, and nuclear applications. Effects of ionization radiations on physical properties of PMMA have greatly studied in recent years. However, to the best of our knowledge, there have been no reports on the effects of ionizing radiations, especially the gamma radiation, on the nonlinear optical properties of PMMA. In this paper, for the first time, detection of large and measurable nonlinear refractive index of PMMA after interaction with the gamma radiation is reported. The optical Z-scan technique is used for measuring the nonlinear optical properties of the gamma-irradiated PMMA samples in the 5–300 kGy dose range. It is shown that variation of the induced nonlinear refractive index in this dose range is more or less linear with deposited dose. A new dosimetry method is proposed, which is based on using the Z-scan technique for measuring the nonlinear refractive index of PMMA and obtaining the amount of absorbed dose using this linear response. The name Z-scan dosimetry is coined for this new dosimetry method. • Large nonlinear refractive index of PMMA after gamma irradiation is reported. • It is shown that variation of nonlinear refractive index with gamma dose is linear. • A new dosimetry method, Z-scan dosimetry, is proposed. • The induced nonlinearity is due to the enhanced C C stretching vibration. [ABSTRACT FROM AUTHOR]