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1.
Polymers (Basel) ; 16(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39000635

RESUMO

Ionizing radiation is vital in various fields but poses health risks, necessitating effective shielding. This study investigated the photon-shielding properties of polyester-based ternary composites with barite (BaSO4) and tungsten (W) using experimental methods, theoretical calculations, and Monte Carlo simulations for energies between 81 keV and 1332.5 keV. WINXCOM was utilized for the theoretical predictions, and the MCNP6 and PHITS 3.22 algorithms were employed for the simulations. According to the results, the simulation, theoretical, and experimental data all closely aligned. At 81 keV, the composite containing the highest amount of tungsten (PBaW50) had the highest mass attenuation coefficient (3.7498 cm2/g) and linear attenuation coefficient (12.9676 cm-1). Furthermore, for a sample that was 1 cm thick, PBaW50 offered 99.88% protection at 81 keV and had the lowest HVL and TVL values. PBaW50 exhibited attenuation capabilities, making it appropriate for use in industrial, medical, and aerospace settings. In summary, the findings of this study underscore the potential of polyester-based composites doped with barite and tungsten as effective materials for gamma radiation shielding. The PBaW50 sample, in particular, stands out for its attenuation performance, making it a viable option for a wide range of applications where durable and efficient radiation shielding is essential.

2.
Appl Radiat Isot ; 208: 111296, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508065

RESUMO

This study aimed to investigate the effect of diabetes on radiation attenuation parameters of the femur and tibia of rats using Monte Carlo Simulations. First, control and diabetic rats were identified and tibias and femurs were removed. Then, the elemental ratios of the bones obtained were calculated using EDS (Energy Dissipative X-ray Spectroscopy). Therefore, radiation permeability properties of control and diabetic bones were simulated by using the content ratios in the bones in MCNP6 (Monte Carlo N-Particle) and PHITS (Particle and Heavy Ion Transport code System) 3.22 and Stopping and Range of Ions in Matter (SRIM) simulation codes. Attenuation coefficient results were compared with the NIST database via XCOM. Although differences in absorption coefficients are observed at low energies, these differences disappear as the energy increases.


Assuntos
Diabetes Mellitus Experimental , Tíbia , Ratos , Animais , Tíbia/diagnóstico por imagem , Projetos Piloto , Simulação por Computador , Fêmur/diagnóstico por imagem , Método de Monte Carlo
3.
Appl Radiat Isot ; 197: 110803, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37054662

RESUMO

Ferrites are ceramic oxide materials consisting of mainly iron oxide and they have become massively important materials commercially and technologically, having a multitude of uses and applications. The protection against neutron-gamma mixed radiation is crucial in several nuclear applications. From this standpoint, mass attenuation coefficient, radiation protection efficiency and transmission factor of some ferrites namely barium, strontium, manganese, copper and cadmium ferrite has been computed using Geant4 and FLUKA simulations. Based on the simulated mass attenuation coefficient, other significant parameters such as linear attenuation coefficient, effective atomic and electron number, conductivity, half value layer, and mean free path were calculated for the selected ferrite materials. The validation of Monte Carlo geometry has been provided by comparing the mass attenuation coefficient results with standard WinXCom data. Gamma ray exposure buildup factors were computed using geometric progression fitting formula for the chosen ferrites in the energy range 0.015-15 MeV at penetration depths up to 40 mfp. The findings of the present work reveal that among the studied ferrites, barium ferrite and copper ferrite possess superior gamma ray and fast neutron attenuation capability, respectively. The present work provides a comprehensive investigation of the selected iron oxides in the field of neutron and gamma ray.

4.
Appl Radiat Isot ; 194: 110688, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36706516

RESUMO

The aim of present investigation is to fabricate TiO2 reinforced novel composites as an alternate nuclear radiation shields. Unsaturated polyester resin has been reinforced by the incorporation of different weight proportions of titanium dioxide (5, 10, 15 and 20 wt%) nanoparticles. Accordingly, mass and linear attenuation coefficients (µm & µ), half and tenth value layers (HVL & TVL), relaxation length (λ) and effective atomic numbers (Zeff) have been computed. Gamma ray transmission set up has been employed for the determination of experimental µm values and consistency of experimental outcomes has been compared with the induced results from WinXCom program and Geant4 simulation code. Moreover, discrepancy of fast neutron removal cross section with the increasing TiO2 content in the prepared composites has been studied. Additionally, structural properties in terms of XRD, SEM, RAMAN, FTIR and mechanical properties in terms of compressive strength have been analysed. The findings of this study revealed that the addition of TiO2 nanoparticles improved the mechanical, nuclear shielding and structural properties of composites. The best gamma ray shielding competency has been showed by the highest TiO2 addition (20%) composite. All in all, UPR + TiO2 composites have been identified as promising alternative radiation shielding candidates owning to their cost effectiveness, ease of processing, good dispersion and lightweightness.

5.
Appl Radiat Isot ; 191: 110568, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36423500

RESUMO

In this study, radiation protection efficiency (RPE) for the coded as UP-Ba0, UP-Ba25, UP-Ba50, UP-Ba75 and UP-Ba100 at different sample thicknesses, total mass attenuation coefficient (µ/ρ), linear attenuation coefficients (µ), half value layers (HVL), tenth value layers (TVL), mean free paths (MFP), effective atomic numbers (Zeff) and effective electron densities (NE) were determined at various gamma energies between 59.5 and 1408.0 keV. With the help of the geometric progression (G-P) fitting method, the energy absorption build-up factor (EABF) and exposure build-up factor (EBF) values were calculated in the energy range from 0.015 MeV to 15 MeV for the produced composites. HPGe detector and eight radioactive sources (241Am, 152Eu, 137Cs, 133Ba, 60Co, 57Co, 54Mn and 22Na) were utilized in the experiment. Experimental results were compared with theoretical calculations and it has been observed that there is a good agreement between theoretical and experimental results. It was observed that RPE, µ/ρ, µ, Zeff and NE parameters increased with increasing barite amount and decreased with increasing energy, while the opposite situation was observed in HVL, TVL and MFP parameters. EABF and EBF values increase with increasing penetration depth. As a result, UP-Ba100 is a good radiation absorber according to the other studied barite filled polymer composites.


Assuntos
Sulfato de Bário , Proteção Radiológica , Polímeros
6.
Appl Radiat Isot ; 157: 109025, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31889681

RESUMO

The L X-ray fluorescence cross-sections at 59.54 keV, L sub-shell fluorescence and Auger yields, L sub-shell level widths, life times and some selected radiative transfer probabilities of L to M, N and O sub-shells were determined using Energy Dispersive X-ray Fluorescence for Th and U. The experiments were performed with a Si(Li) detector and an Am-241 radioactive annular source in excitation geometry. The results are in good agreement with other comparable values within experimental uncertainties.

7.
Appl Radiat Isot ; 115: 295-303, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27451114

RESUMO

The K to Li (i=2,3), K to L, and K to M shell vacancy transfer probabilities for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy and Er were determined at 59.54keV using a reflection geometry. The measurements were performed using an (241)Am annular radioactive source and a high resolution Si(Li) detector. The experimental results were compared with the theoretical values of Hartree-Slater and Hartree-Fock theories, semi-empirical and other available experimental results in the literature. Reasonable agreement is observed between the measured and theoretical results.

8.
Appl Radiat Isot ; 95: 193-199, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25464198

RESUMO

Energy dispersive X-ray fluorescence technique (EDXRF) has been employed for measuring K-shell absorption jump factors and jump ratios for Ti, Cr, Fe, Co, Ni and Cu elements. The jump factors and jump ratios for these elements were determined by measuring K shell fluorescence parameters such as the Kα X-ray production cross-sections, K shell fluorescence yields, Kß-to-Kα X-rays intensity ratios, total atomic absorption cross sections and mass attenuation coefficients. The measurements were performed using a Cd-109 radioactive point source and an Si(Li) detector in direct excitation and transmission experimental geometry. The measured values for jump factors and jump ratios were compared with theoretically calculated and the ones available in the literature.

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