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The effect of substitution Pb2O3 by CuO content was studied for 75% Li2B4O7 + (25 - x)Pb2O3 + xCuO glass system where x = 0, 5, 10, 15, 20, and 25 wt%. The mechanical and radiation shielding properties were evaluated for the investigated glass samples. The mechanical properties included Young's, shear, bulk, longitudinal, Poisson ratio, and micro-hardness were computed theoretically based on the packing factor (Vi) and dissociation energy (Gi) of the metal oxides constituting the existing glass samples using the Makishima-Mackenzie model. The obtained results depicted the insertion of CuO enhances the different mechanical parameters up to 20 mol% of the investigated LBPCu glasses. Furthermore, the radiation shielding properties were studied for the investigated LBPCu glass using the Monte Carlo N-particle transport code (MCNP-5) simulation. MCNP-5 was used to detect the simulated linear attenuation coefficient (LAC) and then mass attenuation coefficient (MAC) and other factors based on various gamma-ray sources with energies of 0.24, 0.66, 1.17, 1.33, and 1.40 MeV. The results showed that LAC's highest value decreased from 0.578 to 0.320 cm-1 for glasses LBPCu0 and LBPCu25, respectively, at low energy of 0.284 MeV. Moreover, the effective and equivalent atomic numbers (Zeff and Zeq), buildup factor (EBF), and absorption buildup factor (EABF) were evaluated for the investigated LBPCu glass using the BXCOM program. The results revealed that the shielding properties of the investigated glasses improved by the insertion of CuO content. © 2020 SECV.Resumen Se estudió el efecto de la sustitución de Pb2O3por el contenido de CuO para el 75% de Li2B4O7+ (25 - x)Pb2O3+ xCuO sistema de vidrio donde x = 0, 5, 10, 15, 20 y 25% en peso. Se evaluaron las propiedades mecánicas y de protección contra la radiación para las muestras de vidrio investigadas. Las propiedades mecánicas incluidas Young, cizallamiento, volumen, longitudinal, relación de Poisson y microdureza se calcularon t

High-density glasses of neodymio-cadmium lead borate of chemical composition xNd2O3/20CdO/20PbO/(57-x)B2O3/3Na2O, where (0 (0Nd) ≤ x ≤ 5 (5Nd) wt%) have been fabricated by a melt quenching process. Physical, structure properties as well as gamma-radiation and neutron shielding effectiveness in wide photon energy range 0.015–15 MeV have been examined. The amorphous nature of xNd-glasses was confirmed, where there was a lack of their crystallinity. Density was gradually increased from 5.006 g/cm3 for 0Nd-glass sample to 5.245 g/cm3 for 5Nd-glass sample. In terms of the mass attenuation coefficient (MAC), introducing Nd3+ ions in the glass matrix has a direct constructive influence on the obtained values of MAC. Generally, the MAC trend follows the order (MAC)5Nd > (MAC)4Nd > (MAC)3Nd > (MAC)2Nd > (MAC)1Nd > (MAC)0Nd. The linear attenuation coefficient (LAC) has a similar trend as MAC for all xNd-glasses. In terms of the half-value layer (T1/2), the 5Nd-glasses possessed the minimum T1/2 values (0.004 cm at 15 keV to 4.301 cm at 15 MeV). Therefore, the T1/2 of the fabricated xNd-glasses has an inverse behavior of the MAC and LAC. Thus, (T1/2)0Nd > (T1/2)1Nd > (T1/2)2Nd > (T1/2)3Nd > (T1/2)4Nd > (T1/2)5Nd. The effective atomic number (Zeff) parameter follows the order (Zeff)5Nd > (Zeff)4Nd > (Zeff)3Nd > (Zeff)2Nd > (Zeff)1Nd > (Zeff)0Nd. In the energies preferred for radiation applications, 5Nd-glasses possess very low exposure (EBF) and energy absorption (EABF) buildup factor values. The fast neutron removal cross-section (FNRC) of the fabricated glasses is improved as the Nd3+ content increases in the glass matrix. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.

In the present work, the nuclear radiation shielding proficiency of eight glassy alloys (Gd25RE25Co25Al25 (RE = Tb, Dy and Ho)) containing different amounts of rare earth elements was investigated with MCNPX simulation codes. Mass attenuation coefficients (μ/ρ) of the glassy alloys were simulated in the energy interval of 0.2-20 MeV by exploiting MCNPX codes, and the generated data were found to match with theoretical WinXCOM results. Next, other crucial photon attenuation parameters, effective atomic number (Zeff), Half Value Layer (HVL), and Mean Free Path (MFP), were gotten out using μ/ρ values. It was seen that Er20Tm20 and Er20Tb20 samples replaced with Er by Gd had the highest Zeff and μ/ρ values, whereas HVL and MFP values were the smallest among the other glassy alloys. Geometric progression (GP) procedure was enjoyed to achieve the exposure and energy absorption buildup factors (EBF and EABF) for the glassy alloys proposed. EABFs and EBFs took the largest and lowest values for Gd25Tb25 and Er20Tm20, respectively, to the other samples. Furthermore, the glassy alloys' neutron reduction abilities were estimated by acquiring fast neutron removal cross-sections (∑R). It was noticed that the ∑R values of the glassy alloys are increased with the rising sample density and seen to be comparable to ∑R values of water and ordinary concrete. The results obtained from this study are important in that they show that glassy alloys can be used as radiation shielding. © 2021 The Author(s). Published by IOP Publishing Ltd.

This study aimed to investigate different types of glasses based on the 46V2 O5-46P2 O5-(8-x) B2 O3-xCuO system in terms of their nuclear radiation shielding properties. Accordingly, five different CuO-doped vanadate glasses were investigated extensively to determine the necessary gamma shielding parameters along with effective conductivity at 300,000 and buildup factors. Phy-x PSD software was used for determination of these vital parameters. Furthermore, these parameters, such as half value layer, tenth value layer, and mean free path were investigated in a broad energy range between 0.015 and 15 MeV. The results revealed that the amount of CuO reinforced in each sample plays an essential role in determination of the shielding abilities of the samples. The sample with the highest CuO content had the highest linear attenuation coefficient and mass attenuation coefficient values. Additionally, the lowest mean free path, half value layer, and tenth value layer values were recorded for glass sample VPCu8. There was an inverse relation between the effective conductivity and effective atomic number and photon energy; that is, as energy increases, the effective conductivity and effective atomic number decreased rapidly, especially in the regions of low energy. Glass sample VPCu8 reported the highest values for both parameters. Moreover, glass sample VPCu8 had the lowest exposure buildup factor and energy absorption buildup factor values. Our findings showed that CuO-reinforced vanadate glass composition, namely 46V2 O5-46P2 O5-8CuO, with a glass density of 2.9235 g/cm3, was reported to have superior gamma ray attenuation properties. These results would be helpful for scientists in determining the most appropriate additive rare earth type, as well as the most appropriate glass composition, to offer shielding characteristics similar to those described above, taking into consideration the criteria for usage and the needs of the community. The results of this research will b

The radiation shielding characteristics of samples from two TeO2 and Sb2O3-based basic glass groups were investigated in this research. TeO2 and Sb2O3-based glasses were determined in the research as six samples with a composition of 10WO3-(x)MoO3-(90 − x)(TeO2/Sb2O3) (x = 10, 20, 30). A general purpose MCNPX Monte Carlo code and Phy-X/PSD platform were used to estimate the radiation shielding characteristics. Accordingly, the linear and mass attenuation coefficients, half value layer, mean free path, variation of the effective atomic number with photon energy, exposure and built-up energy factors, and effective removal cross-section values were determined. It was determined that the results that were produced using the two different techniques were consistent. Based on the collected data, the most remarkable findings were found to be associated with the sample classified as T80 (10WO3 + 10MoO3 + 80TeO2). The current study showed that material density was as equally important as composition in modifying radiation shielding characteristics. With the T80 sample with the greatest density (5.61 g/cm3) achieving the best results. Additionally, the acquired findings were compared to the radiation shielding characteristics of various glass and concrete materials. Increasing the quantity of MoO3 additive, a known heavy metal oxide, in these TeO2 and Sb2O3-based glasses may have a detrimental impact on the change in radiation shielding characteristics. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

X-ray absorption spectroscopy (XAS) is an advanced technique to explore structural information of many types of materials due to its sensitivity and adaptability. Quantum interference of the incoming and outgoing photoelectrons of an absorbing atom reveals the local environment of the absorbing atom and hence a number of fundamental parameters of the material. However, detection of high accuracy data and propagation of experimental uncertainties is limited due to lack of technology. This thesis implemented high accuracy techniques such as the X-ray extended range technique (XERT) and the Hybrid technique to collect high accuracy absorption and fluorescence measurements at ambient temperatures. Protocols of these techniques dictate that systematic errors are investigated over an extended range of experimental parameter space, resulting in better analysis of the mass attenuation coefficients and X-ray absorption fine structure (XAFS) across the K-edge. These techniques can be used to investigate significant systematic errors such as dark currents, blank normalization, harmonics, scattering effects, thickness effect, energy bandwidth, roughness and energy calibration and correct them for precise extended X-ray absorption fine structure (EXAFS) analysis of zinc. The first XERT-like experiment at the Australian Synchrotron was successfully implemented on the XAS beamline to collect high accurate X-ray mass attenuation coefficients across an energy range including the zinc K-absorption edge and XAFS of zinc. Dark current correction was quantified and reached up to 57% for thicker foils and was also significant for thin sample foils. Blank measurements normalized attenuation measurements and scaled thin foil attenuation by 60-500% and even corrected thicker foil attenuation by up to 90%. Discrepancies between different thick foils of up to 20% is corrected using the full-foil mapping technique. The energy was calibrated using standard reference foils. Fluorescence scatteri

The primary aim of this investigation is to synthesize a novel glass system with a composition (35+x) PbO-5TeO2-20Bi2O3-(20-x) MgO-20B2O3 (where x=0, 5, 10, 15, and 20 mol%) by melt quenching method. The confirmation of the amorphous behavior and the presence of the various vibration modes and stretching modes have been analyzed using the XRD and FTIR techniques, respectively. The radiation shielding parameters of these glasses were reported using MCNP5 simulation. The effects of PbO on the MCNP5 parameters were investigated in detail. The mass attenuation coefficient (MAC) was simulated via MCNP5 code, and it was found that the MAC values from MCNP5 all follow the same trend as the XCOM data. The similarity means that the two simulations strongly agree with each other. The linear attenuation coefficient (LAC) was calculated for all the glasses. The glass sample with 55 mol% of the PbO has the greatest LAC at any energy, such as 0.317 at 10 MeV, the lowest investigated energy. From the LAC values, other parameters such as transmission factor (TF), lead equivalent thickness (dlead), and half-value layer (HVL) were reported. The results for the TF of the glasses revealed that the glass systems become more effective as their thickness increases. Glass sample with 35 mol % of the PbO recorded the highest TF at all energies due to its lack of PbO content, such as 15.533% for a thickness of 1 cm and 6.122% for 1.5-cm thickness at 0.3 MeV. The radiation protection efficiency (RPE) was also determined, and we found that the glasses with the greater PbO content and least MgO content have the highest RPE. Therefore, based on the RPE values, glasses with the greater PbO are the most effective radiation shield from the investigated glasses. © 2021, Australian Ceramic Society.

A series of bismo-borate (50-x)B2O3-xTiO2-15Na2O–30Bi2O3 glass samples (where x = 0, 2.5, 5, 7.5, and 10 wt%) doped with TiO2 were fabricated via the melt-quenching technique. The gamma and neutron shielding, physical, optical, and mechanical properties of the prepared samples were investigated. The experimental results were measured using an HPGe detector. 152Eu, 133Ba, 137Cs, and 60Co radioactive sources were used with energies in the range of 81–1408 keV. The experimental results were compared with both the FLUKA code and the XCOM database. The addition of TiO2 increased the density of the glass samples and decreased their molar volume. The mass attenuation coefficient (MAC) decreased as photon energy decreased, while it increased as TiO2 concentration increased. The half value layer (HVL) and mean free path (MFP) of the glass samples increased when the photon energy increased and decreased as the TiO2 concentration increased. The absorbance of the present samples is enhanced by using TiO2, meaning they can be used to protect humans from UV light. Both direct and indirect band gaps decreased as TiO2 content increased from 0 to 10 wt %. Moreover, the electronic transition between localized states is valid in the present samples. The radiation shielding, optical, physical, and mechanical properties of the fabricated glass samples demonstrate their utility for diagnostic gamma shielding. © 2020 Elsevier Ltd and Techna Group S.r.l.

This study points to evaluate the effect of crushed basalt grain size and the press rate on gamma ray shielding properties for some concretes. Nine different concretes were made up of 75% basalt, 25% Portland cement and drops of sodium meta silicate. Three concretes were performed with an average grain size varied between 25 and 107 μm. The other six concretes were performed under different press rate varied between 1.01 and 142.76 kg/cm2 using a hydraulic press. The mass attenuation coefficient (μm) of the prepared concretes was measured using the narrow beam transmission method using a hyper pure germanium detector at gamma ray energies 661.6, 1173.2, 1332.5, 121.8, 244.7, 344.3, 778.9, 964, 1112, 1408 KeV emitted by point sources 137Cs, 60Co and 152Eu. Other important shielding parameters such as half value thickness and radiation protection efficiency were calculated for the prepared concretes at different energies. The obtained experimental data was compared with theoretical data obtained from XCOM program. The results showed that the mass attenuation coefficient was decreased with energy increase, but it increases with grain size decrease. The obtained results showed also that the mass attenuation enhanced by increasing the pressure rate. © 2019 Elsevier Ltd

The radiation shielding effects and elastic properties of adding lead (Pb) and bismuth (Bi) to glasses was analyzed. Six different glasses, coded as G1-G6, were simulated with varying compositions of bismuth oxide and lead oxide, with G1 having the lowest density and G6 having the greatest. MCNP-5 code was used to calculate the mass attenuation coefficient, half value layer, tenth value layer, and mean free path of the glasses, the latter of which was compared with other radiation shields. These parameters were investigated between 0.015 MeV and 15 MeV. The bond compression model was utilized to analyze various parameters that describe the elastic properties of the glass samples. From the ultrasonic wave measurement result, the substitution of PbO and Bi2O3 which working as a network modifier towards SiO2 glass systems would break up the Si–O–Si bonds along with all the formation of non-bridging oxygen's which give the impact in the elastic moduli analysis of the glasses. © 2020 The Authors.

Composition of (50 − x) B2O3–30PbO–20ZnO–xLa2O3 (x = 0, 1.5, 3, 4.5, and 6) wt% glass system were synthesized using quench melt technique and simulated for their nuclear radiation shielding properties. Moreover, UV–visible absorption spectrum among 190–1100 nm and the glass optical parameters were measured. The optical energy gap (Eg), the single-oscillator energy (Eo), the dispersion energy parameter (Ed), refractive index (n), and refractive dispersion index (no) were estimated. The obtained results indicated that (Eg) was decreased with increasing La2O3 content, but the refractive index (n) was increased. The addition of La2O3 to glass network could provide preferable shielding features. The chosen amount of La and another metal oxide has been added to the glass. Shielding parameters such as half-value layer (HVL), mean free path (MFP), mass attenuation coefficient (MAC), and exposure rate in the photon energy range 15–300 keV have been simulated by MicroShield software. These results illustrate that the La5 glass sample has the best radiation shielding properties, among other investigated glasses. This type of glass sample can utilize for the construction of the monitoring screening windows in radiation areas, plats, or screening windows in X-ray diagnostic and for the walls of CT-scanner rooms. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.

by Wing-keung Mak., Thesis (M.Phil.)--Chinese University of Hong Kong, 1995., Includes bibliographical references (leaves 51-53)., Acknowledgments --- p.i, p.ii, Table of Content --- p.iii, Chapter Chapter One --- Introduction --- p.1, Chapter Chapter Two --- Theory, Chapter 2.1 --- Theory of Two-wave Coupling --- p.3, Chapter 2.2 --- Theory of Fanning --- p.8, Chapter 2.3 --- Theory of Time Dependent Absorption Coefficients of Photorefractive Crystals --- p.10, Chapter Chapter Three --- Photorefractive Fabry-Perot Etalon, Chapter 3.1 --- Theory and Numerical Computation --- p.12, Chapter 3.2 --- Summary of Crystal Parameters --- p.15, Chapter 3.3 --- Experimental Studies of Interference Patterns --- p.16, Chapter 3.4 --- Intensity Dependence of Fabry-Perot Etalon Interference Patterns --- p.25, Chapter 3.5 --- Fanning --- p.29, Chapter 3.6 --- Bright Spots on Interference Patterns --- p.31, Chapter Chapter Four --- Time Dependent Absorption Coefficients of Photorefractive Crystals, Chapter 4.1 --- Experiments Using Laser Light --- p.34, Chapter 4.2 --- Experiments Using White Light --- p.44, Chapter Chapter Five --- Conclusion and Future Outlook --- p.49, References --- p.51, http://library.cuhk.edu.hk/record=b5888451, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

The set-up for the measurement of the density of high-temperature melts by means of penetrating gamma-radiation is described. The modern device base, which makes it possible to automatize the work, is the main difference from the earlier existing gamma-densitometers. The key characteristics of the absolute measurements with the use of very exact values of the mass attenuation coefficient for the gamma-quanta beam are described and the accuracy of measurements is estimated. The results of the density measurement of the molten aluminum, cadmium, tin, and bismuth are presented; they confirm the a priori estimate of the error. © 2018, Pleiades Publishing, Ltd.