scholarly journals Investigation on radiation shielding parameters of ordinary, heavy and super heavy concretes

2014 ◽  
Vol 29 (2) ◽  
pp. 149-156 ◽  
Author(s):  
Vishwaanath Singh ◽  
Nagappa Badiger

Shielding of a reactor is required for protection of people and environment during normal operation and accidental situations. In the present paper we investigated the shielding parameters viz. mass attenuation coefficients, linear attenuation coefficients, tenth-value layer, effective atomic numbers, kerma relative to air and exposure buildup factors for gamma-ray for ordinary, heavy, and super heavy concretes. Macroscopic effective removal cross-sections for fast neutron had also been calculated. Ordinary concrete is economically suitable for mixture high energy gamma-ray and neutron as it has large weight fraction of low-Z as compared with super heavy concretes to slow down the neutron. Super heavy concretes are superior shielding for both reactor operation and accident situations. The study is useful for optimizing for shielding design and radiation protection in the reactors.

2020 ◽  
Vol 21 (4) ◽  
pp. 361-368
Author(s):  
A.T. Gheith ◽  
◽  
M.A. El-Sarraf ◽  
I.E. Hasan ◽  
N.L. Helal ◽  
...  

This work is dedicated to figuring out robust epoxy/magnetite/boron carbide (EP/Mag/B4C) composite for radiation attenuation at multiple applications related to nuclear installations, as well as restoration mortar for cracking developed in concrete biological shields. The mechanical properties (flexural, compressive, and impact strengths) and the physical properties (water absorption, porosity, and dry bulk density), each, have been performed to label the composite integrity for practical application. In practice, attenuation properties have been performed by using a collimated beam emitted from spontaneous fission 252Cf (100 μg) neutron source and neutron gamma spectrometer with stilbene scintillator. The pulse shape discrimination technique which would come of the zero cross over method was used to measure the fast neutron and gamma-ray spectra. Thermal neutron fluxes have been measured by using the thermal neutron detection system and the BF-3 detector. The attenuation parameters: precisely, macroscopic effective removal cross-sections ΣR (cm-1), macroscopic cross-sections Σ (cm-1), and total attenuation coefficients μ (cm-1) of fast and thermal neutrons and total gamma-rays respectively were evaluated using the attenuation relations. Also, the MCNP5 code and MERCSF-N program have been used to compute the parameters theoretically. When applicable, measured and calculated results were compared, and it tells us a comprehensive agreement.


2021 ◽  
Vol 11 (22) ◽  
pp. 10904
Author(s):  
M. I. Sayyed ◽  
M. Kh. Hamad ◽  
Mohammad Hasan Abu Mhareb ◽  
K. A. Naseer ◽  
K. A. Mahmoud ◽  
...  

The influence of modifier oxides (TiO2, ZnO, BaO, and PbO) on the mechanical and radiation shielding properties of boro-tellurate glasses is investigated. Samples with a composition of B2O3-SrO-TeO2-RO (RO represents the modifier oxides) were fabricated using the melt quench method, and their physical, mechanical, and radiation attenuation parameters were reported. For this aim, Monte Carlo simulation was employed to predict the radiation attenuation parameters, while the Makishima-Mackenzie model was adopted to determine the mechanical properties. The tightly packed structure with better cross-linkage density is possessed by the Ti-containing glass (SBT-Ti) system among the titled glass batch. The higher Poisson and micro-hardness values of the SBT-Ti glass indicate its structure’s reduced free volume and better compactness. For the glass with PbO, the linear and mass attenuation coefficients are highly increased compared to those glasses doped with TiO2, ZnO, and BaO. The thinner half-value layer was reported at 0.015 MeV, taking values 0.006, 0.005, 0.004, and 0.002 for samples with TiO2, ZnO, BaO, and PbO, respectively. SBT-Pb sample (with PbO) has a thinner HVL compared to other fabricated glass samples. The fabricated glasses’ thickness (Deq) equivalent to 1 cm of lead (Pb) was reported. The results demonstrated that Deq is high at low energy and equals 11.62, 8.81, 7.61, 4.56 cm for SBT-Ti, SBT-Zn, SBT-Ba, and SBT-Pb glass samples, respectively. According to the Deq results, the fabricated glasses have a shielding capacity between 30 and 43% compared to the pure Pb at gamma-ray energy of 1.5 MeV. At high energy (8 MeV), the transmission factor values for a thickness of 1 cm of the fabricated samples reach 88.68, 87.83, 85.95, and 83.11% for glasses SBT-Ti, SBT-Zn, SBT-Ba, and SBT-Pb, respectively.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Vishwanath P. Singh ◽  
N. M. Badiger

The mass attenuation coefficients, μ/ρ, half-value layer, HVL, tenth-value layer, TVL, effective atomic numbers, ZPIeff, and effective electron densities, Ne,eff, of borate glass sample systems of (100-x-y) Na2B4O7 : xPbO : yNiO (where x and y=0, 2, 4, 6, 8, and 10 weight percentage) containing PbO and NiO, with potential gamma ray and neutron shielding applications, have been investigated. The gamma ray interaction parameters, μ/ρ, HVL, TVL, ZPIeff, and Ne,eff, were computed for photon energy range 1 keV–100 GeV. The macroscopic fast neutron removal cross-sections (ΣR) have also been calculated. Appreciable variations were noted for all the interaction parameters by varying the photon energy and the chemical composition of the glass samples. The better shielding properties of borate glass samples containing PbO were found. These results indicated that borate glass samples are a good radiation shielding material.


2018 ◽  
Vol 53 (2) ◽  
pp. 145-148 ◽  
Author(s):  
V.P. Singh ◽  
T. Korkut ◽  
N.M. Badiger

The mass attenuation coefficients of seven different types of normal and heavy concretes like ordinary, hematite-serpentine, ilmenite-limonite, basalt-magnetite, ilmenite, steel-scrap and steel-magnetite concretes has been simulated using FLUKA Monte Carlo code at high energies 1.5, 2, 3, 4, 5 and 6 MeV. The mass attenuation coefficients and linear attenuation coefficient of the concretes were found dependent upon the chemical composition, density and gamma ray energy. FLUKA Monte Carlo code results were found in good agreement with experimental and theoretical XCOM data. Our investigations for high energy gamma-ray interaction validate the FLUKA Monte Carlo code for use where experimental gamma-ray interaction results are not available.


Author(s):  
Gennady Sergeevich, Minasyants ◽  
◽  
Tamara Mihailovna, Minasyants ◽  
Vladimir Mihailovich, Tomozov ◽  
◽  
...  

2020 ◽  
Vol 494 (3) ◽  
pp. 4357-4370
Author(s):  
B Olmi ◽  
D F Torres

ABSTRACT Identification and characterization of a rapidly increasing number of pulsar wind nebulae is, and will continue to be, a challenge of high-energy gamma-ray astrophysics. Given that such systems constitute -by far- the most numerous expected population in the TeV regime, such characterization is important not only to learn about the sources per se from an individual and population perspective, but also to be able to connect them with observations at other frequencies, especially in radio and X-rays. Also, we need to remove the emission from nebulae in highly confused regions of the sky for revealing other underlying emitters. In this paper, we present a new approach for theoretical modelling of pulsar wind nebulae: a hybrid hydrodynamic-radiative model able to reproduce morphological features and spectra of the sources, with relatively limited numerical cost.


2015 ◽  
Vol 16 (6-7) ◽  
pp. 587-599 ◽  
Author(s):  
Bernard Degrange ◽  
Gérard Fontaine

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