A comprehensive study of the energy absorption and exposure buildup factors of different bricks for gamma-rays shielding

The present investigation has been performed on different bricks for the purpose of gamma-ray shielding. The values of the mass attenuation coefficient (µ/ρ), energy absorption buildup factor (EABF) and exposure buildup factor (EBF) were determined and utilized to assess the shielding effectiveness of the bricks under investigation. The mass attenuation coefficients of the selected bricks were calculated theoretically using WinXcom program and compared with MCNPX code. Good agreement between WinXcom and MCNPX results was observed. Furthermore, the EABF and EBF have been discussed as functions of the incident photon energy and penetration depth. It has been found that the EABF and EBF values are very large in the intermediate energy region. The steel slag showed good shielding properties, consequently, this brick is eco-friendly and feasible compared with other types of bricks used for construction. The results in this work should be useful in the construction of effectual shielding against hazardous gamma-rays

Effect of bismuth in lead germanate glass system on shielding properties for development of gamma-rays shielding materials

In this study, the shielding properties of bismuth lead germanate (BPG) glass system in composition x(Bi2O3)40-x(PbO)60(GeO2) where x = 0 to 40 mol% have been investigated. The shielding parameters, mass attenuation coefficients(µ/ρ), mean free path (MFP) and half value layer (HVL) values have been computed using WinXCom program and variation of shielding parameters of the BPG glasses are discussed for the effect of photon energy and Bi2O3 addition into the glasses. The replacement of PbO by Bi2O3 causes an increase in mass attenuation coefficient, while the MFP and HVL values were decreased. The investigation would be very useful for shielding applications in nuclear technologies

Energy-absorption buildup factors and specific absorbed fractions of energy for bioactive glasses

In the present work, effective atomic numbers Zeff, energy-absorption buildup factors EABF and specific absorbed fractions of energy (Φ) for different bioactive glasses have been calculated in the present work. Geometric-Progression (G-P) fitting method was used for computation of EABF. The computed EABF is used to estimate the values of Φ. It is shown that the EABF and Φ are dependent on Zeff and mean free path. In addition, EABF and Φ were the largest for S4 and S7.The results in this work could be useful in choosing a suitable type of these glasses which in turn are able to resist possible radiation damages at human body and to determine the thickness and shape of the bioactive glasses needed

Photon parameters for gamma-rays sensing properties of some oxide of lanthanides

In the present research work, the mass attenuation coefficients (μm) representing the interaction of gamma photons with some oxide of lanthanides (Lu2O3Yb2O3, Er2O3, Sm2O3, Dy2O3, Eu2O3, Nd2O3, Pr6O11, La2O3 and Ce2O3) were investigated using WinXCom software in the wide energy range of 1 keV–100 GeV. The calculated values of μm afterwards were used to evaluate some gamma rays sensing properties as effective atomic effective atomic numbers (Zeff), effective electron densities (Nel), half value layer (HVL) and mean free path (MFP). The computed data observes that, the Lu2O3 shown excellent γ-rays sensing response in the broad energy range. At the absorption edges of the high elements present in the lanthanide compounds, more than a single value of Zeff were found due to the non-uniform variation of µm. Comparisons with experiments wherever possible have been achieved for the calculated µm and Zeff values. The calculated properties are beneficial expanded use of designing in radiation shielding, gas sensors, glass coloring agent and in electronic sensing devices

Comprehensive study on physical, elastic and shielding properties of lead zinc phosphate glasses

A series of ternary phosphate glasses in the form of (PbO)x(ZnO)60-x(P2O5)40 where x = 0–60 mol%, have been successfully prepared by conventional melt-quenching technique. The physical and elastic properties of the glasses have been investigated using pulse echo technique. The longitudinal and shear velocity of the glasses were measured using the MBS8000 ultrasonic data acquisition system at 10 MHz frequency in room temperature. The density, ultrasonic velocity and elastic moduli are found to be composition dependent and the correlation between the elastic moduli with the atomic packing density is discussed in detailed. The shielding parameters, mass attenuation coefficients, half value layers and exposure buildup factor (EBF) values have been computed using WinXCom program with the use of GP fitting method, and variation of shielding parameters are discussed for the effect of PbO addition into the glasses and photon energy. An increase in the density of the glasses results in a change in crosslink density. The sound velocity and elastic properties increased with PbO content and increase in Poisson's ratio trend suggests that the rigidity of the glasses has decreased. Besides, the replacement of ZnO by PbO causes an increase in mass attenuation coefficient, while the half value layer and the exposure buildup factor were decreased and these glasses has been potentially used as shielding material

Sustainable Nanopozzolan Modified Cement: Characterizations and Morphology of Calcium Silicate Hydrate during Hydration

There are environmental and sustainable benefits of partially replacing cement with industrial by-products or synthetic materials in cement based products. Since microstructural behaviours of cement based products are the crucial parameters that govern their sustainability and durability, this study investigates the microstructural comparison between two different types of cement replacements as nanopozzolan modified cement (NPMC) in cement based product by focusing on the evidence of pozzolanic reactivity in corroboration with physical and mechanical properties. Characterization and morphology techniques using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) were carried out to assess the pozzolanic reactivity of cement paste modified with the combination of nano- and micro silica as NPMC in comparison to unmodified cement paste (UCP) of 0.5 water to cement ratio (w/c). Results were then substantiated with compressive strength (CS) results as mechanical property. Results of this study showed clear evidence of pozzolanicity for all samples with varying reactivity with NPMC being the most reactive

Sustainable Nanopozzolan Modified Cement: Characterizations and Morphology of Calcium Silicate Hydrate during Hydration

There are environmental and sustainable benefits of partially replacing cement with industrial by-products or synthetic materials in cement based products. Since microstructural behaviours of cement based products are the crucial parameters that govern their sustainability and durability, this study investigates the microstructural comparison between two different types of cement replacements as nanopozzolan modified cement (NPMC) in cement based product by focusing on the evidence of pozzolanic reactivity in corroboration with physical and mechanical properties. Characterization and morphology techniques using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) were carried out to assess the pozzolanic reactivity of cement paste modified with the combination of nano- and micro silica as NPMC in comparison to unmodified cement paste (UCP) of 0.5 water to cement ratio (w/c). Results were then substantiated with compressive strength (CS) results as mechanical property. Results of this study showed clear evidence of pozzolanicity for all samples with varying reactivity with NPMC being the most reactive

Comprehensive study on physical, elastic and shielding properties of ternary BaO-Bi2O3-P2O5 glasses as a potent radiation shielding material

Recent research studies have been carrying out to characterize the structural, elastic and shielding properties of novel ternary BaO-Bi2O3-P2O5 glasses. The glass series having composition BaO·(50 − x) Bi2O3·50P2O5 (10 ≤ x ≤ 40 wt%) were prepared by conventional melt-quenching technique and the variation in density (ρ), molar volume (Vm), X-ray diffraction (XRD) and ultrasonic velocities has also been studied and correlated with the structural modifications in the glasses. The shielding parameters, effective atomic numbers, half value layers, and exposure buildup factor values have been computed using WinXCom program and G-P fitting method. The variations of shielding parameters were discussed for the effect of Bi2O3 addition into the glasses. The density, ultrasonic velocity and the calculated elastic moduli are found to be composition dependent and discussed in terms of Bi2O3 modifiers. The replacement of BaO by Bi2O3 causes an increase in effective atomic number, while the half value layer and the exposure buildup factor are decreased. This indicates that the increment in the content of Bi2O3 improves the gamma ray shielding characteristics

A facile synthesis of amorphous silica nanoparticles by simple thermal treatment route

A facile thermal treatment route was for the first time used to successfully synthesize amorphous silica nanoparticles. Various techniques were employed to study the structural, phase and elemental composition of the material at different calcination temperature between 500-750oC. The XRD analysis confirms the formation silica to be in an amorphous state and further revealed that the material remained in amorphous state even when calcined at 750oC. The FT-IR spectra shows that the calcination process has enable the removal of organic source from PVP and formation of amorphous silica nanoparticles. The average particle size of the material estimated from the TEM images shows that the particle were <10nm. The optical absorbance exhibited in the UV region reveals amorphous silica nanoparticles possess a wide band gap ranging from 3.803-4.126eV calcined between 500 to 750oC. The EDX analysis has confirmed the presence of Si and O as the only elements in the material formed, which implies thermal treatment method is effective for the synthesis of amorphous silica nanoparticles

Synthesis and elastic properties of ternary ZnO-PbO-TeO2 glasses

Tellurite glass systems in the form [ZnO]x [(TeO2)0.7-PbO)0.3]1-x (x=0, 0.15, 0.17, 0.20, 0.22 and 0.25 mol%) have been prepared by the conventional melt quenching technique. The amorphous and glassy characteristic of samples were confirmed by XRD technique. Both longitudinal and shear ultrasonic velocities were measured by using the pulse-echo method at 5 MHz resonating frequency at room temperature. Elastic moduli (longitudinal modulus, shear modulus, Young’s modulus and Bulk modulus), Poisson’s ratio have been calculated, and the correlation between elastic moduli with those of glass composition is discussed. All elastic constants of the glass system were estimated as well as the microhardness, acoustic impedance, thermal expansion coefficient, softening temperature, and Debye temperature has been determined using the experimental data. The experimental data of the elastic moduli for investigating glasses were compared with those of theoretically calculated values using Makishima-Mackenzie theory, bond compression model and Rocherulle model