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Functional Bi2O3/Gd2O3 Silica-Coated Structures for Improvement of Early Age and Radiation Shielding Performance of Cement Pastes
Data Availability Statement: The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.Copyright © 2024 by the authors. This study presents a new approach towards the production of sol-gel silica-coated Bi2O3/Gd2O3 cement additives towards the improvement of early mechanical performance and radiation attenuation. Two types of silica coatings, which varied in synthesis method and morphology, were used to coat Bi2O3/Gd2O3 structures and evaluated as a cement filler in Portland cement pastes. Isothermal calorimetry studies and early strength evaluations confirmed that both proposed coating types can overcome retarded cement hydration process, attributed to Bi2O3 presence, resulting in improved one day compressive strength by 300% and 251% (depending on coating method) when compared to paste containing pristine Bi2O3 and Gd2O3 particles. Moreover, depending on the type of chosen coating type, various rheological performances of cement pastes can be achieved. Thanks to the proposed combination of materials, both gamma-rays and slow neutron attenuation in cement pastes can be simultaneously improved. The introduction of silica coating resulted in an increment of the gamma-ray and neutron shielding thanks to the increased probability of radiation interaction. Along with the positive early age effects of the synthesized structures, the 28 day mechanical performance of cement pastes was not suppressed, and was found to be comparable to that of the control specimen. As an outcome, silica-coated structures can be successfully used in radiation-shielding cement-based composites, e.g. with demanding early age performances.National Science Centre of Poland within Project no. 2020/39/D/ST8/00975 (SONATA-16)
Prediction of mechanical and radiation parameters of glasses with high Bi2O3 concentration
This study aims to perform multidirectional characterizations on nuclear shielding efficiencies on some bismuth-based glasses. Accordingly, the γattenuation coefficients for xBi2O3-(75-x)B2O3–25Li2O (x = 0, 10, 20, 30, 40, 50, 60 the 70 mol%) were widely evaluated using simulations and theoretical methods. Linear attenuation coefficient (LAC) of the glasses was obtained by the Monte Carlo general-purpose simulation code FLUKA and compared with the XCOM database up to 15 MeV. Moreover, LAC values have been utilized to evaluate related parameters like mass attenuation coefficient (MAC), total molecular cross-section (σt), total atomic cross-section (σa), half-value layer (HVL), total electronic cross-section (σe), mean free path (MFP), effective atomic number (Zeff), and effective electron density (Neff). The results noted that the XCOM and FLUKA data of the shielding parameters are in great agreement. Relatively higher density (5.818 g/cm3), greater LAC, MAC, Zeff, and lower HVL, MFP values are achieved for 70Bi2O3-5B2O3–25Li2O glass. Accordingly, this glass sample is a better gamma shield. © 2021 The AuthorsTaif University Researchers Supporting Project number (TURSP-2020/45) Taif University, Taif, Saudi Arabia
Remarks on the extension and validity of an empirical formula for the fast-neutron removal cross-section: The effective atomic weight
Preparation and characterization of zinc, lanthanum white sand glass for use in nuclear applications
The assessment of natural radioactivity and its associated radiological hazards and dose parameters in granite samples from South Sinai, Egypt
Gamma ray spectra of natural radioactivity from 238U- and 232Th series and from 40K of eight (representing 40 collected samples) granite samples collected from Saint Katherine region, South Sinai, Egypt, had been measured using a gamma-ray spectrometer with an HPGe detector. The results reported in the present article include: Specific activities (A) of 226Ra, 232Th and 40K radionuclides, Radium equivalent activities (Raeq), external and internal hazard indices (Hext, Hint), external and internal level indices (Iγ, Iα), activity utilization index (I), exposure rate (ER) and other important parameters to the subject. The results have been presented in table graphs with the permissible maximum limits
Remarks on the extension and validity of an empirical formula for the fast-neutron removal cross-section:The effective atomic weight
BXCOM: A software for computation of radiation sensing
WOS: 000469740700001The main objective of this work is to develop user-friendly software, called BXCOM, for computation of the exposure build-up factor (EBF) and the energy absorption build-up factor (EABF), using geometric progression (G-P) fitting method for element, compound or mixture in the energy region 0.015-15 MeV, and for penetration depths up to 40 mean free path (mfp). Furthermore, BXCOM can generate the equivalent atomic number and five fitting parameters used in the G-P method for mixtures and compounds over an interval of photon energies extended from 0.015 to 15 MeV. In addition, the program is designed to calculate the effective atomic number and effective electron number via the direct method. BXCOM program has been verified by comparing its results with approved data by American National Standards Institute. BXCOM runs under MS Windows (R) operating system. It has an improved user interface that provides examination of material's radiation interaction parameters. Finally, BXCOM allows rapid and reliable calculation of many gamma-ray interaction parameters such as , , , G-P fitting parameters and build-up factors that are essential in a wide range of applications such as radiation shielding, radiotherapy, technology and so on.Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [2015-115F311]This work was supported by Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [Grant Number 2015-115F311]
Photon attenuation coefficients of Heavy-Metal Oxide glasses by MCNP code, XCOM program and experimental data: A comparison study
Synthesis and Characterization of Zinc-Lead-Phosphate Glasses Doped with Europium for Radiation Shielding
Appropriate glass systems can provide efficient transparent radiation shielding. The current study involved the preparation of the glass system with a composition of xEu2O3-(15-x)ZnO-10CaO-35PbO-40P2O5 (where x = 0, 1, 2, 3, and 4 wt.% Eu2O3). The formation of the glass phase was confirmed using X-ray diffraction (XRD). The study analyzed physical and structural parameters, such as optical conductivity (σopt), refractive index (n), and optical band gap (Eg), with the amount of Eu2O3. The findings indicate that the optical band gap increased as the Eu2O3 content increased. Additionally, a decrease in Urbach energy (EU) was observed, suggesting an improvement in the orderliness of the glass. The study also determined various parameters for gamma-ray shielding, including mass attenuation coefficient (μm), effective atomic number (Zeff), and kerma coefficient (k). For neutron shielding characteristics, the macroscopic effective removal cross-section (ΣR) of fast neutrons was calculated
The effect of cement and aggregate type and w/c ratio on the bound water content and neutron shielding efficiency of concretes
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