18 research outputs found
Mass attenuation coefficients, water and tissue equivalence properties of some tissues by Geant4, XCOM and experimental data
The mass attenuation coefficients (μ/ρ) of some tissues such as muscle (ICRU-44), adipose (ICRP) and blood (Whole) and tissue equivalents such as soft tissue model (H63C6O28N) and water have been investigated using Geant4 simulation tool kit. Appreciable variations have been noted for μ/ρ values by changing the photon energy for the studied tissues. The simulated μ/ρ have been compared with experimental data available in the literature and theoretical XCOM results in the energy region 1 keV–100 GeV, and good agreement has been observed. Also, mass attenuation coefficients relative to water have been calculated in the entire energy region to evaluate the water equivalence of the studied tissues. It is shown that a maximum difference of 8.8 % between water and mentioned soft tissue is observed at 8 keV and soft tissue is found to be a good tissue equivalent for blood and muscle tissue
Influence of lead and zinc oxides on the radiation shielding properties of tellurite glass systems
The radiation shielding properties of xPbO-(100-x)TeO2, x = 10, 20, and 30 mol% binary glasses and y[ZnO]-(100-y)[70(TeO2)-30(PbO)] y = 15, 20, and 25 mol% ternary glasses were investigated using Geant4 simulations and the newly developed Phy-X/PSD program. The glasses’ gamma shielding abilities were assessed using their mass attenuation coefficient (μ/ρ), mean free path (MFP), effective atomic number (Zeff), and half value layer (HVL) values. The neutron shielding ability was evaluated by determining the removal cross-section (RCS) values, which were 0.097, 0.101, and 0.103 cm-1 for binary PbO-TeO2 (PT) glasses and 0.118, 0.116, and 0.114 cm-1 for ternary ZnO-PbO-TeO2 (PTZ) glasses. The gamma and neutron shielding features of the glasses were compared with those of various ordinary concretes and Pb-free, Pb-based, and commercial glasses. The addition of PbO changed the gamma and neutron properties of the PT glasses, while the addition of ZnO demonstrated a different trend in the gamma properties of the PTZ glass system
Study on gamma-ray buildup factors of bismuth borate glasses
Energy absorption buildup factor (EABF) and exposure buildup factor (EBF) of bismuth borate glass systems in structure (75-x)B2O3-xBi2O3-10Na2O-10CaO-5Al2O3 (0x25) have been investigated for photon energy region between 0.015 and 15 MeV and for penetration depths of 1-40 mfp. Five parameters (G-P) fitting method has been carried out for computations procedure. The calculated values of EABF and EBF have been observed to be dependent on photon energy, penetration depths and on the concentration of Bi2O3 mol% in the glass sample. It has been found that BOB25 glass offers better gamma-ray shielding than other samples. In addition, the values of EABF and EBF have been compared and significant differences up to 8% have been noted in intermediate energy region
Mass attenuation coefficients, effective atomic numbers and electron densities of some contrast agents for computed tomography
In the clinical computed tomography (CT) examinations, a photon is attenuated as it passes a patient by tissues and contrast agents (CAs). The CM can increase the visibility of internal structures or fluids within the patient. In this work, we have investigated the photon interaction parameters of some CT contrast agents such as iotrolan, iodixanol, iohexol, ioxilan, ioversol, and iomeprol. The mass attenuation coefficients (mu/rho) of these contrast agents have been determined using Geant4 code in the energy range from 1 keV to 1 MeV for total photon interaction. The validity of the Geant4 code was verified by comparing the simulation results with those calculated by the XCOM program. A very good agreement was observed between mu/rho values obtained by both Geant4 and XCOM codes. The mu/rho values were then used to estimate the effective atomic numbers (Z(eff)) and electron densities (N-eff) for the selected CT contrast agents. It was found that the values of mu/rho, Z(eff) and N-eff depend on the photon energy and increase with increasing iodine concentration in the composition of CAs. Also, the Z(eff) values were observed in the range of 6-50 and the N-eff values were observed in the range of 2 - 21 (10(23) electron/g). The present study would be helpful to develop new CT contrast agents to serve in vivo imaging applications
Mass attenuation coefficients, water and tissue equivalence properties of some tissues by Geant4, XCOM and experimental data
433-437The mass attenuation coefficients (μ/ρ) of some tissues such as muscle (ICRU-44), adipose (ICRP) and blood (Whole) and tissue equivalents such as soft tissue model (H63C6O28N) and water have been investigated using Geant4 simulation tool kit. Appreciable variations have been noted for μ/ρ values by changing the photon energy for the studied tissues. The simulated μ/ρ have been compared with experimental data available in the literature and theoretical XCOM results in the energy region 1 keV–100 GeV, and good agreement has been observed. Also, mass attenuation coefficients relative to water have been calculated in the entire energy region to evaluate the water equivalence of the studied tissues. It is shown that a maximum difference of 8.8 % between water and mentioned soft tissue is observed at 8 keV and soft tissue is found to be a good tissue equivalent for blood and muscle tissue
Nuclear Radiation Shielding Characteristics of Some Natural Rocks by Using EPICS2017 Library
Radiation leakage is a serious problem in various technological applications. In this paper, radiation shielding characteristics of some natural rocks are elucidated. Mass attenuation coefficients (µ/ρ) of these rocks are obtained at different photon energies with the help of the EPICS2017 library. The obtained µ/ρ values are confirmed via the theoretical XCOM program by determining the correlation factor and relative deviation between both of these methods. Then, effective atomic number (Zeff), absorption length (MFP), and half value layer (HVL) are evaluated by applying the µ/ρ values. The maximum μ/ρ values of the natural rocks were observed at 0.37 MeV. At this energy, the Zeff values of the natural rocks were 16.23, 16.97, 17.28, 10.43, and 16.65 for olivine basalt, jet black granite, limestone, sandstone, and dolerite, respectively. It is noted that the radiation shielding features of the selected natural rocks are higher than that of conventional concrete and comparable with those of commercial glasses. Therefore, the present rocks can be used in various radiation shielding applications, and they have many advantages for being clean and low-cost products. In addition, we found that the EPICS2017 library is useful in determining the radiation shielding parameters for the rocks and may be used for further calculations for other rocks and construction building materials
Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy and nuclear radiation shielding properties of [α-Fe3+O(OH)]-doped lithium borate glasses
Synthesis of graphene-based Ag-doped CuFe2O4 composite for improved photocatalytic activity against industrial effluents
Copper ferrite (CuFe2O4, CF) and silver-doped copper ferrite (Ag-CuFe2O4, ACF) were prepared via co-precipitation method. While nano-composite of ACF with rGO was prepared by ultra-sonication approach. Degradation of crystal violet (CV) and benzoic acid (BA) by CF, ACF, and ACF@rGO was conducted under sunlight. Because of tremendous stability and immense surface area of rGO, it shows good ability to transfer electrons during photocatalysis.Band gap for CF and ACF were tuned having values 1.36 and 1.67 eV. Ag-CuFe2O4@rGO has exhibited greater photo-catalytic activity than a bare and doped sample. 82.7% and 48.4% were degradation % of CV and BA by Ag-CuFe2O4@rGO respectively. Ag-CuFe2O4@rGO showed 1.3 times higher efficiency than bare CuFe2O4. ACF was sonicated with rGO and composite was formed which was not reported before and I was the novelty of this paper. The photodegradation ability and cyclic stability etc. was increased after the formation of composite
Electric Poling Effect on Piezocatalytic BaTiO3/Polymer Composites for Coatings
BaTiO3-polymer paint composites were fabricated to examine piezocatalysis activities. Dye degradation and antibacterial activities were recorded under ultrasonication. The effect of polarization was also examined for the catalysis process. There were significant enhancements in catalysis performance in the poled sample; 80–90% dye degradation was recorded (240 min) in poled samples of BaTiO3-polymer paint composites. The above observations indicate that these composites can be utilized as coatings for self-cleaning applications